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[apple/xnu.git] / iokit / Kernel / IOServicePM.cpp
index 3e5822be1eb6be38846e6e109c69d5ca76937109..5cdc56a78209b57c92be5b383ea728a1dc7a3784 100644 (file)
@@ -1,17 +1,20 @@
 /*
- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2016 Apple Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
- * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- * 
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
-#include <IOKit/IOService.h>
-#include <IOKit/IOLib.h>
-#include <IOKit/IOCommandGate.h>
-#include <IOKit/IOTimerEventSource.h>
-#include <IOKit/IOWorkLoop.h>
-#include <IOKit/IOPlatformExpert.h>
+
 #include <IOKit/assert.h>
-#include <IOKit/IOMessage.h>
 #include <IOKit/IOKitDebug.h>
+#include <IOKit/IOLib.h>
+#include <IOKit/IOMessage.h>
+#include <IOKit/IOPlatformExpert.h>
+#include <IOKit/IOService.h>
+#include <IOKit/IOEventSource.h>
+#include <IOKit/IOWorkLoop.h>
+#include <IOKit/IOCommand.h>
 #include <IOKit/IOTimeStamp.h>
-#include <IOKit/pwr_mgt/RootDomain.h>
+#include <IOKit/IOReportMacros.h>
+#include <IOKit/IODeviceTreeSupport.h>
+
+#include <IOKit/pwr_mgt/IOPMlog.h>
 #include <IOKit/pwr_mgt/IOPMinformee.h>
-#include "IOKit/pwr_mgt/IOPMinformeeList.h"
-#include "IOKit/pwr_mgt/IOPMchangeNoteList.h"
-#include "IOKit/pwr_mgt/IOPMlog.h"
-#include "IOKit/pwr_mgt/IOPowerConnection.h"
-#include <kern/clock.h>
+#include <IOKit/pwr_mgt/IOPMinformeeList.h>
+#include <IOKit/pwr_mgt/IOPowerConnection.h>
+#include <IOKit/pwr_mgt/RootDomain.h>
+#include <IOKit/pwr_mgt/IOPMPrivate.h>
+
+#include <sys/proc.h>
+#include <sys/proc_internal.h>
+#include <sys/sysctl.h>
+#include <libkern/OSDebug.h>
+#include <kern/thread.h>
+
+// Required for notification instrumentation
+#include "IOServicePrivate.h"
+#include "IOServicePMPrivate.h"
+#include "IOKitKernelInternal.h"
 
-#define super IORegistryEntry
 
-// Some debug functions
-static inline void
-ioSPMTrace(unsigned int csc,
-          unsigned int a = 0, unsigned int b = 0,
-          unsigned int c = 0, unsigned int d = 0)
+static void settle_timer_expired(thread_call_param_t, thread_call_param_t);
+static void idle_timer_expired(thread_call_param_t, thread_call_param_t);
+static void tellKernelClientApplier(OSObject * object, void * arg);
+static void tellAppClientApplier(OSObject * object, void * arg);
+
+static uint64_t
+computeTimeDeltaNS( const AbsoluteTime * start )
 {
-    if (gIOKitDebug & kIOLogTracePower)
-       IOTimeStampConstant(IODBG_POWER(csc), a, b, c, d);
+       AbsoluteTime    now;
+       uint64_t        nsec;
+
+       clock_get_uptime(&now);
+       SUB_ABSOLUTETIME(&now, start);
+       absolutetime_to_nanoseconds(now, &nsec);
+       return nsec;
 }
 
-static inline void
-ioSPMTraceStart(unsigned int csc,
-               unsigned int a = 0, unsigned int b = 0,
-               unsigned int c = 0, unsigned int d = 0)
+#if PM_VARS_SUPPORT
+OSDefineMetaClassAndStructors(IOPMprot, OSObject)
+#endif
+
+//******************************************************************************
+// Globals
+//******************************************************************************
+
+static bool                  gIOPMInitialized       = false;
+static uint32_t              gIOPMBusyRequestCount  = 0;
+static uint32_t              gIOPMWorkInvokeCount   = 0;
+static uint32_t              gIOPMTickleGeneration  = 0;
+static IOWorkLoop *          gIOPMWorkLoop          = NULL;
+static IOPMRequestQueue *    gIOPMRequestQueue      = NULL;
+static IOPMRequestQueue *    gIOPMReplyQueue        = NULL;
+static IOPMWorkQueue *       gIOPMWorkQueue         = NULL;
+static IOPMCompletionQueue * gIOPMCompletionQueue   = NULL;
+static IOPMRequest *         gIOPMRequest           = NULL;
+static IOService *           gIOPMRootNode          = NULL;
+static IOPlatformExpert *    gPlatform              = NULL;
+
+
+const OSSymbol *             gIOPMPowerClientDevice     = NULL;
+const OSSymbol *             gIOPMPowerClientDriver     = NULL;
+const OSSymbol *             gIOPMPowerClientChildProxy = NULL;
+const OSSymbol *             gIOPMPowerClientChildren   = NULL;
+const OSSymbol *             gIOPMPowerClientRootDomain = NULL;
+
+static const OSSymbol *      gIOPMPowerClientAdvisoryTickle = NULL;
+static bool                  gIOPMAdvisoryTickleEnabled = true;
+static thread_t              gIOPMWatchDogThread        = NULL;
+uint32_t                     gCanSleepTimeout           = 0;
+
+static uint32_t
+getPMRequestType( void )
 {
-    if (gIOKitDebug & kIOLogTracePower)
-       IOTimeStampConstant(IODBG_POWER(csc)|DBG_FUNC_START, a, b, c, d);
+       uint32_t type = kIOPMRequestTypeInvalid;
+       if (gIOPMRequest) {
+               type = gIOPMRequest->getType();
+       }
+       return type;
 }
 
-static inline void
-ioSPMTraceEnd(unsigned int csc,
-             unsigned int a = 0, unsigned int b = 0,
-             unsigned int c = 0, unsigned int d = 0)
+static IOPMRequestTag
+getPMRequestTag( void )
 {
-    if (gIOKitDebug & kIOLogTracePower)
-       IOTimeStampConstant(IODBG_POWER(csc)|DBG_FUNC_END, a, b, c, d);
+       IOPMRequestTag tag = 0;
+       if (gIOPMRequest &&
+           (gIOPMRequest->getType() == kIOPMRequestTypeRequestPowerStateOverride)) {
+               tag = gIOPMRequest->fRequestTag;
+       }
+       return tag;
 }
 
+SYSCTL_UINT(_kern, OID_AUTO, pmtimeout, CTLFLAG_RW | CTLFLAG_LOCKED, &gCanSleepTimeout, 0, "Power Management Timeout");
+
+//******************************************************************************
+// Macros
+//******************************************************************************
+
+#define PM_ERROR(x...)              do { kprintf(x);IOLog(x); \
+                                   } while (false)
+#define PM_LOG(x...)                do { kprintf(x); } while (false)
+
+#define PM_LOG1(x...)               do {  \
+                                   if (kIOLogDebugPower & gIOKitDebug) \
+                                       kprintf(x); } while (false)
+
+#define PM_LOG2(x...)               do {  \
+                                   if (kIOLogDebugPower & gIOKitDebug) \
+                                       kprintf(x); } while (false)
+
+#if 0
+#define PM_LOG3(x...)               do { kprintf(x); } while (false)
+#else
+#define PM_LOG3(x...)
+#endif
+
+#define RD_LOG(x...)                do { \
+                                   if ((kIOLogPMRootDomain & gIOKitDebug) && \
+                                       (getPMRootDomain() == this)) { \
+                                       kprintf("PMRD: " x); \
+                                   }} while (false)
+#define PM_ASSERT_IN_GATE(x)          \
+do {                                  \
+    assert(gIOPMWorkLoop->inGate());  \
+} while(false)
+
+#define PM_LOCK()                   IOLockLock(fPMLock)
+#define PM_UNLOCK()                 IOLockUnlock(fPMLock)
+#define PM_LOCK_SLEEP(event, dl)    IOLockSleepDeadline(fPMLock, event, dl, THREAD_UNINT)
+#define PM_LOCK_WAKEUP(event)       IOLockWakeup(fPMLock, event, false)
+
+#define us_per_s                    1000000
+#define ns_per_us                   1000
+#define k30Seconds                  (30*us_per_s)
+#define k5Seconds                   ( 5*us_per_s)
+#if CONFIG_EMBEDDED
+#define kCanSleepMaxTimeReq         k5Seconds
+#else
+#define kCanSleepMaxTimeReq         k30Seconds
+#endif
+#define kMaxTimeRequested           k30Seconds
+#define kMinAckTimeoutTicks         (10*1000000)
+#define kIOPMTardyAckSPSKey         "IOPMTardyAckSetPowerState"
+#define kIOPMTardyAckPSCKey         "IOPMTardyAckPowerStateChange"
+#define kPwrMgtKey                  "IOPowerManagement"
+
+#define OUR_PMLog(t, a, b) do {                 \
+    if (pwrMgt) {                               \
+       if (gIOKitDebug & kIOLogPower)          \
+           pwrMgt->pmPrint(t, a, b);           \
+       if (gIOKitTrace & kIOTracePowerMgmt)    \
+           pwrMgt->pmTrace(t, DBG_FUNC_NONE, a, b);        \
+    }                                           \
+    } while(0)
+
+#define OUR_PMLogFuncStart(t, a, b) do {        \
+    if (pwrMgt) {                               \
+       if (gIOKitDebug & kIOLogPower)          \
+           pwrMgt->pmPrint(t, a, b);           \
+       if (gIOKitTrace & kIOTracePowerMgmt)    \
+           pwrMgt->pmTrace(t, DBG_FUNC_START, a, b);       \
+    }                                           \
+    } while(0)
+
+#define OUR_PMLogFuncEnd(t, a, b) do {          \
+    if (pwrMgt) {                               \
+       if (gIOKitDebug & kIOLogPower)          \
+           pwrMgt->pmPrint(-t, a, b);          \
+       if (gIOKitTrace & kIOTracePowerMgmt)    \
+           pwrMgt->pmTrace(t, DBG_FUNC_END, a, b);        \
+    }                                           \
+    } while(0)
+
+#define NS_TO_MS(nsec)              ((int)((nsec) / 1000000ULL))
+#define NS_TO_US(nsec)              ((int)((nsec) / 1000ULL))
+
+#define SUPPORT_IDLE_CANCEL         1
+
+#define kIOPMPowerStateMax          0xFFFFFFFF
+#define kInvalidTicklePowerState    kIOPMPowerStateMax
+
+#define kNoTickleCancelWindow       (60ULL * 1000ULL * 1000ULL * 1000ULL)
+
+#define IS_PM_ROOT                  (this == gIOPMRootNode)
+#define IS_ROOT_DOMAIN              (getPMRootDomain() == this)
+#define IS_POWER_DROP               (StateOrder(fHeadNotePowerState) < StateOrder(fCurrentPowerState))
+#define IS_POWER_RISE               (StateOrder(fHeadNotePowerState) > StateOrder(fCurrentPowerState))
+
+// log setPowerStates longer than (ns):
+#if defined(__i386__) || defined(__x86_64__)
+#define LOG_SETPOWER_TIMES          (300ULL * 1000ULL * 1000ULL)
+#else
+#define LOG_SETPOWER_TIMES          (50ULL * 1000ULL * 1000ULL)
+#endif
+// log app responses longer than (ns):
+#define LOG_APP_RESPONSE_TIMES      (100ULL * 1000ULL * 1000ULL)
+// use message tracer to log messages longer than (ns):
+#define LOG_APP_RESPONSE_MSG_TRACER (3 * 1000ULL * 1000ULL * 1000ULL)
+
+// log kext responses longer than (ns):
+#define LOG_KEXT_RESPONSE_TIMES     (100ULL * 1000ULL * 1000ULL)
+
+enum {
+       kReserveDomainPower = 1
+};
 
-static void ack_timer_expired(thread_call_param_t);
-static void settle_timer_expired(thread_call_param_t);
-static void PM_idle_timer_expired(OSObject *, IOTimerEventSource *);
-static void c_PM_Clamp_Timer_Expired (OSObject * client,IOTimerEventSource *);
-void tellAppWithResponse ( OSObject * object, void * context);
-void tellClientWithResponse ( OSObject * object, void * context);
-void tellClient ( OSObject * object, void * context);
-IOReturn serializedAllowPowerChange ( OSObject *, void *, void *, void *, void *);
-IOReturn serializedCancelPowerChange ( OSObject *, void *, void *, void *, void *);
+#define MS_PUSH(n)  \
+    do { assert(kIOPM_BadMachineState == fSavedMachineState); \
+        assert(kIOPM_BadMachineState != n); \
+        fSavedMachineState = n; } while (false)
 
-extern const IORegistryPlane * gIOPowerPlane;
+#define MS_POP()    \
+    do { assert(kIOPM_BadMachineState != fSavedMachineState); \
+        fMachineState = fSavedMachineState; \
+        fSavedMachineState = kIOPM_BadMachineState; } while (false)
 
+#define PM_ACTION_0(a) \
+    do { if (fPMActions.a) { \
+        (fPMActions.a)(fPMActions.target, this, &fPMActions); } \
+        } while (false)
 
-// and there's 1000 nanoseconds in a microsecond:
-#define ns_per_us 1000
+#define PM_ACTION_2(a, x, y) \
+    do { if (fPMActions.a) { \
+        (fPMActions.a)(fPMActions.target, this, &fPMActions, x, y, \
+           getPMRequestTag()); } \
+        } while (false)
 
+#define PM_ACTION_3(a, x, y, z) \
+    do { if (fPMActions.a) { \
+        (fPMActions.a)(fPMActions.target, this, &fPMActions, x, y, z); } \
+        } while (false)
 
-// The current change note is processed by a state machine.
-// Inputs are acks from interested parties, ack from the controlling driver,
-// ack timeouts, settle timeout, and powerStateDidChange from the parent.
-// These are the states:
-enum {
-    kIOPM_OurChangeTellClientsPowerDown = 1,
-    kIOPM_OurChangeTellPriorityClientsPowerDown,
-    kIOPM_OurChangeNotifyInterestedDriversWillChange,
-    kIOPM_OurChangeSetPowerState,
-    kIOPM_OurChangeWaitForPowerSettle,
-    kIOPM_OurChangeNotifyInterestedDriversDidChange,
-    kIOPM_OurChangeFinish,
-    kIOPM_ParentDownTellPriorityClientsPowerDown_Immediate,
-    kIOPM_ParentDownNotifyInterestedDriversWillChange_Delayed,
-    kIOPM_ParentDownWaitForPowerSettleAndNotifyDidChange_Immediate,
-    kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed,
-    kIOPM_ParentDownSetPowerState_Delayed,
-    kIOPM_ParentDownWaitForPowerSettle_Delayed,
-    kIOPM_ParentDownAcknowledgeChange_Delayed,
-    kIOPM_ParentUpSetPowerState_Delayed,
-    kIOPM_ParentUpSetPowerState_Immediate,
-    kIOPM_ParentUpWaitForSettleTime_Delayed,
-    kIOPM_ParentUpNotifyInterestedDriversDidChange_Delayed,
-    kIOPM_ParentUpAcknowledgePowerChange_Delayed,
-    kIOPM_Finished
-};
+static OSNumber * copyClientIDForNotification(
+       OSObject *object,
+       IOPMInterestContext *context);
+
+static void logClientIDForNotification(
+       OSObject *object,
+       IOPMInterestContext *context,
+       const char *logString);
+
+//*********************************************************************************
+// PM machine states
+//
+// Check kgmacros after modifying machine states.
+//*********************************************************************************
 
-// values of outofbandparameter
 enum {
-       kNotifyApps,
-       kNotifyPriority
+       kIOPM_Finished                                      = 0,
+
+       kIOPM_OurChangeTellClientsPowerDown                 = 1,
+       kIOPM_OurChangeTellUserPMPolicyPowerDown            = 2,
+       kIOPM_OurChangeTellPriorityClientsPowerDown         = 3,
+       kIOPM_OurChangeNotifyInterestedDriversWillChange    = 4,
+       kIOPM_OurChangeSetPowerState                        = 5,
+       kIOPM_OurChangeWaitForPowerSettle                   = 6,
+       kIOPM_OurChangeNotifyInterestedDriversDidChange     = 7,
+       kIOPM_OurChangeTellCapabilityDidChange              = 8,
+       kIOPM_OurChangeFinish                               = 9,
+
+       kIOPM_ParentChangeTellPriorityClientsPowerDown      = 10,
+       kIOPM_ParentChangeNotifyInterestedDriversWillChange = 11,
+       kIOPM_ParentChangeSetPowerState                     = 12,
+       kIOPM_ParentChangeWaitForPowerSettle                = 13,
+       kIOPM_ParentChangeNotifyInterestedDriversDidChange  = 14,
+       kIOPM_ParentChangeTellCapabilityDidChange           = 15,
+       kIOPM_ParentChangeAcknowledgePowerChange            = 16,
+
+       kIOPM_NotifyChildrenStart                           = 17,
+       kIOPM_NotifyChildrenOrdered                         = 18,
+       kIOPM_NotifyChildrenDelayed                         = 19,
+       kIOPM_SyncTellClientsPowerDown                      = 20,
+       kIOPM_SyncTellPriorityClientsPowerDown              = 21,
+       kIOPM_SyncNotifyWillChange                          = 22,
+       kIOPM_SyncNotifyDidChange                           = 23,
+       kIOPM_SyncTellCapabilityDidChange                   = 24,
+       kIOPM_SyncFinish                                    = 25,
+       kIOPM_TellCapabilityChangeDone                      = 26,
+       kIOPM_DriverThreadCallDone                          = 27,
+
+       kIOPM_BadMachineState                               = 0xFFFFFFFF
 };
 
+//*********************************************************************************
+// [public] PMinit
+//
+// Initialize power management.
+//*********************************************************************************
+
+void
+IOService::PMinit( void )
+{
+       if (!initialized) {
+               if (!gIOPMInitialized) {
+                       gPlatform = getPlatform();
+                       gIOPMWorkLoop = IOWorkLoop::workLoop();
+                       if (gIOPMWorkLoop) {
+                               gIOPMRequestQueue = IOPMRequestQueue::create(
+                                       this, OSMemberFunctionCast(IOPMRequestQueue::Action,
+                                       this, &IOService::actionPMRequestQueue));
+
+                               gIOPMReplyQueue = IOPMRequestQueue::create(
+                                       this, OSMemberFunctionCast(IOPMRequestQueue::Action,
+                                       this, &IOService::actionPMReplyQueue));
+
+                               gIOPMWorkQueue = IOPMWorkQueue::create(this,
+                                   OSMemberFunctionCast(IOPMWorkQueue::Action, this,
+                                   &IOService::actionPMWorkQueueInvoke),
+                                   OSMemberFunctionCast(IOPMWorkQueue::Action, this,
+                                   &IOService::actionPMWorkQueueRetire));
+
+                               gIOPMCompletionQueue = IOPMCompletionQueue::create(
+                                       this, OSMemberFunctionCast(IOPMCompletionQueue::Action,
+                                       this, &IOService::actionPMCompletionQueue));
+
+                               if (gIOPMWorkLoop->addEventSource(gIOPMRequestQueue) !=
+                                   kIOReturnSuccess) {
+                                       gIOPMRequestQueue->release();
+                                       gIOPMRequestQueue = NULL;
+                               }
+
+                               if (gIOPMWorkLoop->addEventSource(gIOPMReplyQueue) !=
+                                   kIOReturnSuccess) {
+                                       gIOPMReplyQueue->release();
+                                       gIOPMReplyQueue = NULL;
+                               }
+
+                               if (gIOPMWorkLoop->addEventSource(gIOPMWorkQueue) !=
+                                   kIOReturnSuccess) {
+                                       gIOPMWorkQueue->release();
+                                       gIOPMWorkQueue = NULL;
+                               }
+
+                               // Must be added after the work queue, which pushes request
+                               // to the completion queue without signaling the work loop.
+                               if (gIOPMWorkLoop->addEventSource(gIOPMCompletionQueue) !=
+                                   kIOReturnSuccess) {
+                                       gIOPMCompletionQueue->release();
+                                       gIOPMCompletionQueue = NULL;
+                               }
+
+                               gIOPMPowerClientDevice =
+                                   OSSymbol::withCStringNoCopy( "DevicePowerState" );
+
+                               gIOPMPowerClientDriver =
+                                   OSSymbol::withCStringNoCopy( "DriverPowerState" );
+
+                               gIOPMPowerClientChildProxy =
+                                   OSSymbol::withCStringNoCopy( "ChildProxyPowerState" );
+
+                               gIOPMPowerClientChildren =
+                                   OSSymbol::withCStringNoCopy( "ChildrenPowerState" );
+
+                               gIOPMPowerClientAdvisoryTickle =
+                                   OSSymbol::withCStringNoCopy( "AdvisoryTicklePowerState" );
+
+                               gIOPMPowerClientRootDomain =
+                                   OSSymbol::withCStringNoCopy( "RootDomainPower" );
+                       }
+
+                       if (gIOPMRequestQueue && gIOPMReplyQueue && gIOPMCompletionQueue) {
+                               gIOPMInitialized = true;
+                       }
+               }
+               if (!gIOPMInitialized) {
+                       return;
+               }
+
+               pwrMgt = new IOServicePM;
+               pwrMgt->init();
+               setProperty(kPwrMgtKey, pwrMgt);
+
+               queue_init(&pwrMgt->WorkChain);
+               queue_init(&pwrMgt->RequestHead);
+               queue_init(&pwrMgt->PMDriverCallQueue);
+
+               fOwner                      = this;
+               fPMLock                     = IOLockAlloc();
+               fInterestedDrivers          = new IOPMinformeeList;
+               fInterestedDrivers->initialize();
+               fDesiredPowerState          = kPowerStateZero;
+               fDeviceDesire               = kPowerStateZero;
+               fInitialPowerChange         = true;
+               fInitialSetPowerState       = true;
+               fPreviousRequestPowerFlags  = 0;
+               fDeviceOverrideEnabled      = false;
+               fMachineState               = kIOPM_Finished;
+               fSavedMachineState          = kIOPM_BadMachineState;
+               fIdleTimerMinPowerState     = kPowerStateZero;
+               fActivityLock               = IOLockAlloc();
+               fStrictTreeOrder            = false;
+               fActivityTicklePowerState   = kInvalidTicklePowerState;
+               fAdvisoryTicklePowerState   = kInvalidTicklePowerState;
+               fControllingDriver          = NULL;
+               fPowerStates                = NULL;
+               fNumberOfPowerStates        = 0;
+               fCurrentPowerState          = kPowerStateZero;
+               fParentsCurrentPowerFlags   = 0;
+               fMaxPowerState              = kPowerStateZero;
+               fName                       = getName();
+               fParentsKnowState           = false;
+               fSerialNumber               = 0;
+               fResponseArray              = NULL;
+               fNotifyClientArray          = NULL;
+               fCurrentPowerConsumption    = kIOPMUnknown;
+               fOverrideMaxPowerState      = kIOPMPowerStateMax;
+
+               if (!gIOPMRootNode && (getParentEntry(gIOPowerPlane) == getRegistryRoot())) {
+                       gIOPMRootNode = this;
+                       fParentsKnowState = true;
+               } else if (getProperty(kIOPMResetPowerStateOnWakeKey) == kOSBooleanTrue) {
+                       fResetPowerStateOnWake = true;
+               }
+
+               if (IS_ROOT_DOMAIN) {
+                       fWatchdogTimer = thread_call_allocate(
+                               &IOService::watchdog_timer_expired, (thread_call_param_t)this);
+                       fWatchdogLock = IOLockAlloc();
+
+                       fBlockedArray =  OSArray::withCapacity(4);
+               }
+
+               fAckTimer = thread_call_allocate(
+                       &IOService::ack_timer_expired, (thread_call_param_t)this);
+               fSettleTimer = thread_call_allocate(
+                       &settle_timer_expired, (thread_call_param_t)this);
+               fIdleTimer = thread_call_allocate(
+                       &idle_timer_expired, (thread_call_param_t)this);
+               fDriverCallEntry = thread_call_allocate(
+                       (thread_call_func_t) &IOService::pmDriverCallout, this);
+               assert(fDriverCallEntry);
+
+               // Check for powerChangeDone override.
+               if (OSMemberFunctionCast(void (*)(void),
+                   getResourceService(), &IOService::powerChangeDone) !=
+                   OSMemberFunctionCast(void (*)(void),
+                   this, &IOService::powerChangeDone)) {
+                       fPCDFunctionOverride = true;
+               }
+
+#if PM_VARS_SUPPORT
+               IOPMprot * prot = new IOPMprot;
+               if (prot) {
+                       prot->init();
+                       prot->ourName = fName;
+                       prot->thePlatform = gPlatform;
+                       fPMVars = prot;
+                       pm_vars = prot;
+               }
+#else
+               pm_vars = (void *) (uintptr_t) true;
+#endif
+
+               initialized = true;
+       }
+}
 
-// used for applyToInterested
-struct context {
-    OSArray *  responseFlags;
-    UInt16     serialNumber;
-    UInt16     counter;
-    UInt32     maxTimeRequested;
-    int                msgType;
-    IOService *        us;
-    IOLock *   flags_lock;
-    unsigned long stateNumber;
-    IOPMPowerFlags stateFlags;
-};
+//*********************************************************************************
+// [private] PMfree
+//
+// Free the data created by PMinit. Only called from IOService::free().
+//*********************************************************************************
 
-// five minutes in microseconds
-#define FIVE_MINUTES 5*60*1000000
-#define k30seconds 30*1000000
+void
+IOService::PMfree( void )
+{
+       initialized = false;
+       pm_vars = NULL;
+
+       if (pwrMgt) {
+               assert(fMachineState == kIOPM_Finished);
+               assert(fInsertInterestSet == NULL);
+               assert(fRemoveInterestSet == NULL);
+               assert(fNotifyChildArray == NULL);
+               assert(queue_empty(&pwrMgt->RequestHead));
+               assert(queue_empty(&fPMDriverCallQueue));
+
+               if (fWatchdogTimer) {
+                       thread_call_cancel(fWatchdogTimer);
+                       thread_call_free(fWatchdogTimer);
+                       fWatchdogTimer = NULL;
+               }
+
+               if (fWatchdogLock) {
+                       IOLockFree(fWatchdogLock);
+                       fWatchdogLock = NULL;
+               }
+
+               if (fBlockedArray) {
+                       fBlockedArray->release();
+                       fBlockedArray = NULL;
+               }
+
+               if (fSettleTimer) {
+                       thread_call_cancel(fSettleTimer);
+                       thread_call_free(fSettleTimer);
+                       fSettleTimer = NULL;
+               }
+               if (fAckTimer) {
+                       thread_call_cancel(fAckTimer);
+                       thread_call_free(fAckTimer);
+                       fAckTimer = NULL;
+               }
+               if (fIdleTimer) {
+                       thread_call_cancel(fIdleTimer);
+                       thread_call_free(fIdleTimer);
+                       fIdleTimer = NULL;
+               }
+               if (fDriverCallEntry) {
+                       thread_call_free(fDriverCallEntry);
+                       fDriverCallEntry = NULL;
+               }
+               if (fPMLock) {
+                       IOLockFree(fPMLock);
+                       fPMLock = NULL;
+               }
+               if (fActivityLock) {
+                       IOLockFree(fActivityLock);
+                       fActivityLock = NULL;
+               }
+               if (fInterestedDrivers) {
+                       fInterestedDrivers->release();
+                       fInterestedDrivers = NULL;
+               }
+               if (fDriverCallParamSlots && fDriverCallParamPtr) {
+                       IODelete(fDriverCallParamPtr, DriverCallParam, fDriverCallParamSlots);
+                       fDriverCallParamPtr = NULL;
+                       fDriverCallParamSlots = 0;
+               }
+               if (fResponseArray) {
+                       fResponseArray->release();
+                       fResponseArray = NULL;
+               }
+               if (fNotifyClientArray) {
+                       fNotifyClientArray->release();
+                       fNotifyClientArray = NULL;
+               }
+               if (fPowerStates && fNumberOfPowerStates) {
+                       IODelete(fPowerStates, IOPMPSEntry, fNumberOfPowerStates);
+                       fNumberOfPowerStates = 0;
+                       fPowerStates = NULL;
+               }
+               if (fPowerClients) {
+                       fPowerClients->release();
+                       fPowerClients = NULL;
+               }
+
+#if PM_VARS_SUPPORT
+               if (fPMVars) {
+                       fPMVars->release();
+                       fPMVars = NULL;
+               }
+#endif
+
+               pwrMgt->release();
+               pwrMgt = NULL;
+       }
+}
 
-/*
- There are two different kinds of power state changes.  One is initiated by a subclassed device object which has either
- decided to change power state, or its controlling driver has suggested it, or some other driver wants to use the
- idle device and has asked it to become usable.  The second kind of power state change is initiated by the power
- domain parent.  The two are handled slightly differently.
-
-There is a queue of so-called change notifications, or change notes for short.  Usually the queue is empty, and when
- it isn't, usually there is one change note in it, but since it's possible to have more than one power state change pending
- at one time, a queue is implemented.  Example:  the subclass device decides it's idle and initiates a change to a lower
- power state.  This causes interested parties to be notified, but they don't all acknowledge right away.  This causes the
- change note to sit in the queue until all the acks are received.  During this time, the device decides it isn't idle anymore and
- wants to raise power back up again.  This change can't be started, however, because the previous one isn't complete yet,
- so the second one waits in the queue.  During this time, the parent decides to lower or raise the power state of the entire
- power domain and notifies the device, and that notification goes into the queue, too, and can't be actioned until the
- others are.
-
- This is how a power change initiated by the subclass device is handled:
- First, all interested parties are notified of the change via their powerStateWillChangeTo method.  If they all don't
- acknowledge via return code, then we have to wait.  If they do, or when they finally all acknowledge via our
- acknowledgePowerChange method, then we can continue.  We call the controlling driver, instructing it to change to
- the new state.  Then we wait for power to settle.  If there is no settling-time, or after it has passed, we notify
- interested parties again, this time via their powerStateDidChangeTo methods.  When they have all acked, we're done.
- If we lowered power and don't need the power domain to be in its current power state, we suggest to the parent that
- it lower the power domain state.
-
- This is how a change to a lower power domain state initiated by the parent is handled:
- First, we figure out what power state we will be in when the new domain state is reached.  Then all interested parties are
- notified that we are moving to that new state.  When they have acknowledged, we call the controlling driver to assume
- that state and we wait for power to settle.  Then we acknowledge our preparedness to our parent.  When all its interested
- parties have acknowledged, it lowers power and then notifies its interested parties again.  When we get this call, we notify
- our interested parties that the power state has changed, and when they have all acknowledged, we're done.
-
- This is how a change to a higher power domain state initiated by the parent is handled:
- We figure out what power state we will be in when the new domain state is reached.  If it is different from our current
- state we acknowledge the parent.  When all the parent's interested parties have acknowledged, it raises power in the
-domain and waits for power to settle.  Then it  notifies everyone that the new state has been reached.  When we get this call,
- we call the controlling driver, instructing it  to assume the new state, and wait for power to settle.  Then we notify our interested
- parties.  When they all acknowledge  we are done.
-
- In either of the two cases above, it is possible that we will not be changing state even though the domain is.  Examples:
- A change to a lower domain state may not affect us because we are already in a low enough state, and
- We will not take advantage of a change to a higher domain state, because we have no need of the higher power.
- In such a case, there is nothing to do but acknowledge the parent.  So when the parent calls our powerDomainWillChange
- method, and we decide that we will not be changing state, we merely acknowledge the parent, via return code, and wait.
- When the parent subsequently calls powerStateDidChange, we acknowledge again via return code, and the change is complete.
-
- Power state changes are processed in a state machine, and since there are four varieties of power state changes, there are
- four major paths through the state machine:
-
- The fourth is nearly trivial.  In this path, the parent is changing the domain state, but we are not changing the device state.
- The change starts when the parent calls powerDomainWillChange.  All we do is acknowledge the parent.
-When the parent calls powerStateDidChange, we acknowledge the parent again, and we're done.
-
- The first is fairly simple.  It starts when a power domain child calls requestPowerDomainState and we decide to change power states
- to accomodate the child, or if our power-controlling driver calls changePowerStateTo, or if some other driver which is using our
- device calls makeUsable, or if a subclassed object calls changePowerStateToPriv.  These are all power changes initiated by us, not
- forced upon us by the parent.  We start by notifying interested parties.  If they all acknowledge via return code, we can go
- on to state "OurChangeSetPowerState".  Otherwise, we start the ack timer and wait for the stragglers to acknowlege by calling
- acknowledgePowerChange.  We move on to state "OurChangeSetPowerState" when all the stragglers have acknowledged,
- or when the ack timer expires on all those which didn't acknowledge.  In "OurChangeSetPowerState" we call the power-controlling
- driver to change the power state of the hardware.  If it returns saying it has done so, we go on to state "OurChangeWaitForPowerSettle".
- Otherwise, we have to wait for it, so we set the ack timer and wait.  When it calls acknowledgeSetPowerState, or when the
- ack timer expires, we go on.  In "OurChangeWaitForPowerSettle", we look in the power state array to see if there is any settle time required
- when changing from our current state to the new state.  If not, we go right away to "OurChangeNotifyInterestedDriversDidChange".  Otherwise, we
- set the settle timer and wait.  When it expires, we move on.  In "OurChangeNotifyInterestedDriversDidChange" state, we notify all our interested parties
- via their powerStateDidChange methods that we have finished changing power state.  If they all acknowledge via return
- code, we move on to "OurChangeFinish".  Otherwise we set the ack timer and wait.  When they have all acknowledged, or
- when the ack timer has expired for those that didn't, we move on to "OurChangeFinish", where we remove the used
- change note from the head of the queue and start the next one if one exists.
-
- Parent-initiated changes are more complex in the state machine.  First, power going up and power going down are handled
- differently, so they have different paths throught the state machine.  Second, we can acknowledge the parent's notification
- in two different ways, so each of the parent paths is really two.
-
- When the parent calls our powerDomainWillChange method, notifying us that it will lower power in the domain, we decide
- what state that will put our device in.  Then we embark on the state machine path "IOPMParentDownSetPowerState_Immediate"
- and "kIOPM_ParentDownWaitForPowerSettleAndNotifyDidChange_Immediate", in which we notify interested parties of the upcoming change,  instruct our driver to make
- the change, check for settle time, and notify interested parties of the completed change.   If we get to the end of this path without
- stalling due to an interested party which didn't acknowledge via return code, due to the controlling driver not able to change
- state right away, or due to a non-zero settling time, then we return IOPMAckImplied to the parent, and we're done with the change.
- If we do stall in any of those states, we return IOPMWillAckLater to the parent and enter the parallel path "kIOPM_ParentDownSetPowerState_Delayed"
- "kIOPM_ParentDownWaitForPowerSettle_Delayed", and "kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed", where we continue with the same processing, except that at the end we
- acknowledge the parent explicitly via acknowledgePowerChange, and we're done with the change.
-Then when the parent calls us at powerStateDidChange we acknowledging via return code, because we have already made
- the power change.  In any case, when we are done we remove the used change note from the head of the queue and start on the next one.
-
- The case of the parent raising power in the domain is handled similarly in that there are parallel paths, one for no-stall
- that ends in implicit acknowleging the parent, and one that has stalled at least once that ends in explicit acknowledging
- the parent.  This case is different, though in that our device changes state in the second half, after the parent calls
- powerStateDidChange rather than before, as in the power-lowering case.
-
- When the parent calls our powerDomainWillChange method, notifying us that it will raise power in the domain, we acknowledge
- via return code, because there's really nothing we can do until the power is actually raised in the domain.
- When the parent calls us at powerStateDidChange, we start by notifying our interested parties.  If they all acknowledge via return code,
- we go on to" kIOPM_ParentUpSetPowerState_Immediate" to instruct the driver to raise its power level. After that, we check for any
- necessary settling time in "IOPMParentUpWaitForSettleTime_Immediate", and we notify all interested parties that power has changed
- in "IOPMParentUpNotifyInterestedDriversDidChange_Immediate".  If none of these operations stall, we acknowledge the parent via return code, release
- the change note, and start the next, if there is one.  If one of them does stall, we enter the parallel path  "kIOPM_ParentUpSetPowerState_Delayed",
- "kIOPM_ParentUpWaitForSettleTime_Delayed", "kIOPM_ParentUpNotifyInterestedDriversDidChange_Delayed", and "kIOPM_ParentUpAcknowledgePowerChange_Delayed", which ends with
- our explicit acknowledgement to the parent.
-
-*/
-
-
-const char priv_key[ ] = "Power Management private data";
-const char prot_key[ ] = "Power Management protected data";
-
-
-void IOService::PMinit ( void )
-{
-    if ( ! initialized ) {
-
-        // make space for our variables
-        pm_vars =  new IOPMprot;                                       
-        priv = new IOPMpriv;
-        pm_vars->init();
-        priv->init();
-        
-
-        // add pm_vars & priv to the properties
-        setProperty(prot_key, (OSObject *) pm_vars);                   
-        setProperty(priv_key, (OSObject *) priv);
-
-        // then initialize them
-        priv->owner = this;
-        pm_vars->theNumberOfPowerStates = 0;                           
-        priv->we_are_root = false;
-        pm_vars->theControllingDriver = NULL;
-        priv->our_lock = IOLockAlloc();
-        priv->flags_lock = IOLockAlloc();
-        priv->queue_lock = IOLockAlloc();
-        pm_vars->childLock = IOLockAlloc();
-        pm_vars->parentLock = IOLockAlloc();
-        priv->interestedDrivers = new IOPMinformeeList;
-        priv->interestedDrivers->initialize();
-        priv->changeList = new IOPMchangeNoteList;
-        priv->changeList->initialize();
-        pm_vars->aggressiveness = 0;
-        for (unsigned int i = 0; i <= kMaxType; i++) 
-        {
-               pm_vars->current_aggressiveness_values[i] = 0;
-               pm_vars->current_aggressiveness_valid[i] = false;
-        }
-        pm_vars->myCurrentState =  0;
-        priv->imminentState = 0;
-        priv->ourDesiredPowerState = 0;
-        pm_vars->parentsCurrentPowerFlags = 0;
-        pm_vars->maxCapability = 0;
-        priv->driverDesire = 0;
-        priv->deviceDesire = 0;
-        priv->initial_change = true;
-        priv->need_to_become_usable = false;
-        priv->previousRequest = 0;
-        priv->device_overrides = false;
-        priv->machine_state = kIOPM_Finished;
-        priv->timerEventSrc = NULL;
-        priv->clampTimerEventSrc = NULL;
-        pm_vars->PMworkloop = NULL;
-        priv->activityLock = NULL;
-        pm_vars->ourName = getName();
-        pm_vars->thePlatform = getPlatform();
-        pm_vars->parentsKnowState = false;
-        assert( pm_vars->thePlatform != 0 );
-        priv->clampOn = false;
-        pm_vars->serialNumber = 0;
-        pm_vars->responseFlags = NULL;
-        pm_vars->doNotPowerDown = true;
-        pm_vars->PMcommandGate = NULL;
-        priv->ackTimer = thread_call_allocate((thread_call_func_t)ack_timer_expired, (thread_call_param_t)this);
-        priv->settleTimer = thread_call_allocate((thread_call_func_t)settle_timer_expired, (thread_call_param_t)this);
-        initialized = true;
-    }
-}
-
-
-//*********************************************************************************
-// PMfree
-//
-// Free up the data created in PMinit, if it exists.
-//*********************************************************************************
-void IOService::PMfree ( void )
-{
-    if ( priv ) {
-        if (  priv->clampTimerEventSrc != NULL ) {
-            getPMworkloop()->removeEventSource(priv->clampTimerEventSrc);
-            priv->clampTimerEventSrc->release();
-            priv->clampTimerEventSrc = NULL;
-        }
-        if (  priv->timerEventSrc != NULL ) {
-            pm_vars->PMworkloop->removeEventSource(priv->timerEventSrc);
-            priv->timerEventSrc->release();
-            priv->timerEventSrc = NULL;
-        }
-        if ( priv->settleTimer ) {
-            thread_call_cancel(priv->settleTimer);
-            thread_call_free(priv->settleTimer);
-            priv->settleTimer = NULL;
-        }
-        if ( priv->ackTimer ) {
-            thread_call_cancel(priv->ackTimer);
-            thread_call_free(priv->ackTimer);
-            priv->ackTimer = NULL;
-        }
-        if ( priv->our_lock ) {
-            IOLockFree(priv->our_lock);
-            priv->our_lock = NULL;
-        }
-        if ( priv->flags_lock ) {
-            IOLockFree(priv->flags_lock);
-            priv->flags_lock = NULL;
-        }
-        if ( priv->activityLock ) {
-            IOLockFree(priv->activityLock);
-            priv->activityLock = NULL;
-        }
-        priv->interestedDrivers->release();
-        priv->changeList->release();
-        // remove instance variables
-        priv->release();                               
-    }
-    
-    if ( pm_vars ) {
-        if ( pm_vars->PMcommandGate ) {
-            pm_vars->PMcommandGate->release();
-            pm_vars->PMcommandGate = NULL;
-        }
-        if ( pm_vars->PMworkloop ) {
-            // The work loop object returned from getPMworkLoop() is
-            // never retained, therefore it should not be released.
-            // pm_vars->PMworkloop->release();
-            pm_vars->PMworkloop = NULL;
-        }
-        if ( pm_vars->responseFlags ) {
-            pm_vars->responseFlags->release();
-            pm_vars->responseFlags = NULL;
-        }
-        // remove instance variables
-        pm_vars->release();                            
-    }
-}
-
-
-//*********************************************************************************
-// PMstop
-//
-// Disconnect the node from its parents and children in the Power Plane.
-//*********************************************************************************
-void IOService::PMstop ( void )
-{
-    OSIterator *       iter;
-    OSObject *         next;
-    IOPowerConnection *        connection;
-    IOService *                theChild;
-    IOService *                theParent;
-
-    // remove the properties
-    removeProperty(prot_key);                  
-    removeProperty(priv_key);
-    
-    // detach parents
-    iter = getParentIterator(gIOPowerPlane);   
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                theParent = (IOService *)connection->copyParentEntry(gIOPowerPlane);
-                if ( theParent ) 
-                {
-                    theParent->removePowerChild(connection);
-                    theParent->release();
-                }
-            }
-        }
-        iter->release();
-    }
-
-    // detach IOConnections   
-    detachAbove( gIOPowerPlane );              
-    
-    // no more power state changes
-    pm_vars->parentsKnowState = false;         
-
-    // detach children
-    iter = getChildIterator(gIOPowerPlane);    
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                theChild = ((IOService *)(connection->copyChildEntry(gIOPowerPlane)));
-                if ( theChild ) 
-                {
-                    // detach nub from child
-                    connection->detachFromChild(theChild,gIOPowerPlane);       
-                    theChild->release();
-                }
-                // detach us from nub
-                detachFromChild(connection,gIOPowerPlane);                     
-            }
-        }
-        iter->release();
-    }
-
-    // Remove all interested drivers from the list, including the power
-    // controlling driver.
-    //
-    // Usually, the controlling driver and the policy-maker functionality
-    // are implemented by the same object, and without the deregistration,
-    // the object will be holding an extra retain on itself, and cannot
-    // be freed.
-
-    if ( priv && priv->interestedDrivers )
-    {
-        IOPMinformee * informee;
-
-        while (( informee = priv->interestedDrivers->firstInList() ))
-            deRegisterInterestedDriver( informee->whatObject );
-    }
-}
-
-
-//*********************************************************************************
-// joinPMtree
+void
+IOService::PMDebug( uint32_t event, uintptr_t param1, uintptr_t param2 )
+{
+       OUR_PMLog(event, param1, param2);
+}
+
+//*********************************************************************************
+// [public] joinPMtree
 //
 // A policy-maker calls its nub here when initializing, to be attached into
 // the power management hierarchy.  The default function is to call the
 // platform expert, which knows how to do it.  This method is overridden
-// by a nub subclass which may either know how to do it, or may need
-// to take other action.
+// by a nub subclass which may either know how to do it, or may need to
+// take other action.
 //
 // This may be the only "power management" method used in a nub,
 // meaning it may not be initialized for power management.
 //*********************************************************************************
-void IOService::joinPMtree ( IOService * driver )
+
+void
+IOService::joinPMtree( IOService * driver )
 {
-    IOPlatformExpert * thePlatform;
+       IOPlatformExpert *  platform;
 
-    thePlatform = getPlatform();
-    assert(thePlatform != 0 );
-    thePlatform->PMRegisterDevice(this,driver);
+       platform = getPlatform();
+       assert(platform != NULL);
+       platform->PMRegisterDevice(this, driver);
 }
 
-
+#ifndef __LP64__
 //*********************************************************************************
-// youAreRoot
+// [deprecated] youAreRoot
 //
 // Power Managment is informing us that we are the root power domain.
-// The only difference between us and any other power domain is that
-// we have no parent and therefore never call it.
 //*********************************************************************************
-IOReturn IOService::youAreRoot ( void )
-{    
-    priv-> we_are_root = true;
-    pm_vars->parentsKnowState = true;
-    attachToParent( getRegistryRoot(),gIOPowerPlane );
-    
-    return IOPMNoErr;
+
+IOReturn
+IOService::youAreRoot( void )
+{
+       return IOPMNoErr;
+}
+#endif /* !__LP64__ */
+
+//*********************************************************************************
+// [public] PMstop
+//
+// Immediately stop driver callouts. Schedule an async stop request to detach
+// from power plane.
+//*********************************************************************************
+
+void
+IOService::PMstop( void )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return;
+       }
+
+       PM_LOCK();
+
+       if (fLockedFlags.PMStop) {
+               PM_LOG2("%s: PMstop() already stopped\n", fName);
+               PM_UNLOCK();
+               return;
+       }
+
+       // Inhibit future driver calls.
+       fLockedFlags.PMStop = true;
+
+       // Wait for all prior driver calls to finish.
+       waitForPMDriverCall();
+
+       PM_UNLOCK();
+
+       // The rest of the work is performed async.
+       request = acquirePMRequest( this, kIOPMRequestTypePMStop );
+       if (request) {
+               PM_LOG2("%s: %p PMstop\n", getName(), OBFUSCATE(this));
+               submitPMRequest( request );
+       }
+}
+
+//*********************************************************************************
+// [private] handlePMstop
+//
+// Disconnect the node from all parents and children in the power plane.
+//*********************************************************************************
+
+void
+IOService::handlePMstop( IOPMRequest * request )
+{
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * connection;
+       IOService *         theChild;
+       IOService *         theParent;
+
+       PM_ASSERT_IN_GATE();
+       PM_LOG2("%s: %p %s start\n", getName(), OBFUSCATE(this), __FUNCTION__);
+
+       // remove driver from prevent system sleep lists
+       getPMRootDomain()->updatePreventIdleSleepList(this, false);
+       getPMRootDomain()->updatePreventSystemSleepList(this, false);
+
+       // remove the property
+       removeProperty(kPwrMgtKey);
+
+       // detach parents
+       iter = getParentIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((connection = OSDynamicCast(IOPowerConnection, next))) {
+                               theParent = (IOService *)connection->copyParentEntry(gIOPowerPlane);
+                               if (theParent) {
+                                       theParent->removePowerChild(connection);
+                                       theParent->release();
+                               }
+                       }
+               }
+               iter->release();
+       }
+
+       // detach IOConnections
+       detachAbove( gIOPowerPlane );
+
+       // no more power state changes
+       fParentsKnowState = false;
+
+       // detach children
+       iter = getChildIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((connection = OSDynamicCast(IOPowerConnection, next))) {
+                               theChild = ((IOService *)(connection->copyChildEntry(gIOPowerPlane)));
+                               if (theChild) {
+                                       // detach nub from child
+                                       connection->detachFromChild(theChild, gIOPowerPlane);
+                                       theChild->release();
+                               }
+                               // detach us from nub
+                               detachFromChild(connection, gIOPowerPlane);
+                       }
+               }
+               iter->release();
+       }
+
+       // Remove all interested drivers from the list, including the power
+       // controlling driver.
+       //
+       // Usually, the controlling driver and the policy-maker functionality
+       // are implemented by the same object, and without the deregistration,
+       // the object will be holding an extra retain on itself, and cannot
+       // be freed.
+
+       if (fInterestedDrivers) {
+               IOPMinformeeList *  list = fInterestedDrivers;
+               IOPMinformee *      item;
+
+               PM_LOCK();
+               while ((item = list->firstInList())) {
+                       list->removeFromList(item->whatObject);
+               }
+               PM_UNLOCK();
+       }
+
+       // Clear idle period to prevent idleTimerExpired() from servicing
+       // idle timer expirations.
+
+       fIdleTimerPeriod = 0;
+       if (fIdleTimer && thread_call_cancel(fIdleTimer)) {
+               release();
+       }
+
+       PM_LOG2("%s: %p %s done\n", getName(), OBFUSCATE(this), __FUNCTION__);
+}
+
+//*********************************************************************************
+// [public] addPowerChild
+//
+// Power Management is informing us who our children are.
+//*********************************************************************************
+
+IOReturn
+IOService::addPowerChild( IOService * child )
+{
+       IOPowerConnection * connection  = NULL;
+       IOPMRequest *       requests[3] = {NULL, NULL, NULL};
+       OSIterator *        iter;
+       bool                ok = true;
+
+       if (!child) {
+               return kIOReturnBadArgument;
+       }
+
+       if (!initialized || !child->initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       OUR_PMLog( kPMLogAddChild, (uintptr_t) child, 0 );
+
+       do {
+               // Is this child already one of our children?
+
+               iter = child->getParentIterator( gIOPowerPlane );
+               if (iter) {
+                       IORegistryEntry *   entry;
+                       OSObject *          next;
+
+                       while ((next = iter->getNextObject())) {
+                               if ((entry = OSDynamicCast(IORegistryEntry, next)) &&
+                                   isChild(entry, gIOPowerPlane)) {
+                                       ok = false;
+                                       break;
+                               }
+                       }
+                       iter->release();
+               }
+               if (!ok) {
+                       PM_LOG2("%s: %s (%p) is already a child\n",
+                           getName(), child->getName(), OBFUSCATE(child));
+                       break;
+               }
+
+               // Add the child to the power plane immediately, but the
+               // joining connection is marked as not ready.
+               // We want the child to appear in the power plane before
+               // returning to the caller, but don't want the caller to
+               // block on the PM work loop.
+
+               connection = new IOPowerConnection;
+               if (!connection) {
+                       break;
+               }
+
+               // Create a chain of PM requests to perform the bottom-half
+               // work from the PM work loop.
+
+               requests[0] = acquirePMRequest(
+                       /* target */ this,
+                       /* type */ kIOPMRequestTypeAddPowerChild1 );
+
+               requests[1] = acquirePMRequest(
+                       /* target */ child,
+                       /* type */ kIOPMRequestTypeAddPowerChild2 );
+
+               requests[2] = acquirePMRequest(
+                       /* target */ this,
+                       /* type */ kIOPMRequestTypeAddPowerChild3 );
+
+               if (!requests[0] || !requests[1] || !requests[2]) {
+                       break;
+               }
+
+               requests[0]->attachNextRequest( requests[1] );
+               requests[1]->attachNextRequest( requests[2] );
+
+               connection->init();
+               connection->start(this);
+               connection->setAwaitingAck(false);
+               connection->setReadyFlag(false);
+
+               attachToChild( connection, gIOPowerPlane );
+               connection->attachToChild( child, gIOPowerPlane );
+
+               // connection needs to be released
+               requests[0]->fArg0 = connection;
+               requests[1]->fArg0 = connection;
+               requests[2]->fArg0 = connection;
+
+               submitPMRequests( requests, 3 );
+               return kIOReturnSuccess;
+       }while (false);
+
+       if (connection) {
+               connection->release();
+       }
+       if (requests[0]) {
+               releasePMRequest(requests[0]);
+       }
+       if (requests[1]) {
+               releasePMRequest(requests[1]);
+       }
+       if (requests[2]) {
+               releasePMRequest(requests[2]);
+       }
+
+       // Silent failure, to prevent platform drivers from adding the child
+       // to the root domain.
+
+       return kIOReturnSuccess;
+}
+
+//*********************************************************************************
+// [private] addPowerChild1
+//
+// Step 1/3 of adding a power child. Called on the power parent.
+//*********************************************************************************
+
+void
+IOService::addPowerChild1( IOPMRequest * request )
+{
+       IOPMPowerStateIndex tempDesire = kPowerStateZero;
+
+       // Make us temporary usable before adding the child.
+
+       PM_ASSERT_IN_GATE();
+       OUR_PMLog( kPMLogMakeUsable, kPMLogMakeUsable, 0 );
+
+       if (fControllingDriver && inPlane(gIOPowerPlane) && fParentsKnowState) {
+               tempDesire = fHighestPowerState;
+       }
+
+       if ((tempDesire != kPowerStateZero) &&
+           (IS_PM_ROOT || (StateOrder(fMaxPowerState) >= StateOrder(tempDesire)))) {
+               adjustPowerState(tempDesire);
+       }
+}
+
+//*********************************************************************************
+// [private] addPowerChild2
+//
+// Step 2/3 of adding a power child. Called on the joining child.
+// Execution blocked behind addPowerChild1.
+//*********************************************************************************
+
+void
+IOService::addPowerChild2( IOPMRequest * request )
+{
+       IOPowerConnection * connection = (IOPowerConnection *) request->fArg0;
+       IOService *         parent;
+       IOPMPowerFlags      powerFlags;
+       bool                knowsState;
+       unsigned long       powerState;
+       unsigned long       tempDesire;
+
+       PM_ASSERT_IN_GATE();
+       parent = (IOService *) connection->getParentEntry(gIOPowerPlane);
+
+       if (!parent || !inPlane(gIOPowerPlane)) {
+               PM_LOG("%s: addPowerChild2 not in power plane\n", getName());
+               return;
+       }
+
+       // Parent will be waiting for us to complete this stage.
+       // It is safe to directly access parent's vars.
+
+       knowsState = (parent->fPowerStates) && (parent->fParentsKnowState);
+       powerState = parent->fCurrentPowerState;
+
+       if (knowsState) {
+               powerFlags = parent->fPowerStates[powerState].outputPowerFlags;
+       } else {
+               powerFlags = 0;
+       }
+
+       // Set our power parent.
+
+       OUR_PMLog(kPMLogSetParent, knowsState, powerFlags);
+
+       setParentInfo( powerFlags, connection, knowsState );
+
+       connection->setReadyFlag(true);
+
+       if (fControllingDriver && fParentsKnowState) {
+               fMaxPowerState = fControllingDriver->maxCapabilityForDomainState(fParentsCurrentPowerFlags);
+               // initially change into the state we are already in
+               tempDesire = fControllingDriver->initialPowerStateForDomainState(fParentsCurrentPowerFlags);
+               fPreviousRequestPowerFlags = (IOPMPowerFlags)(-1);
+               adjustPowerState(tempDesire);
+       }
+
+       getPMRootDomain()->tagPowerPlaneService(this, &fPMActions);
 }
 
+//*********************************************************************************
+// [private] addPowerChild3
+//
+// Step 3/3 of adding a power child. Called on the parent.
+// Execution blocked behind addPowerChild2.
+//*********************************************************************************
+
+void
+IOService::addPowerChild3( IOPMRequest * request )
+{
+       IOPowerConnection * connection = (IOPowerConnection *) request->fArg0;
+       IOService *         child;
+       IOPMrootDomain *    rootDomain = getPMRootDomain();
+
+       PM_ASSERT_IN_GATE();
+       child = (IOService *) connection->getChildEntry(gIOPowerPlane);
+
+       if (child && inPlane(gIOPowerPlane)) {
+               if ((this != rootDomain) && child->getProperty("IOPMStrictTreeOrder")) {
+                       PM_LOG1("%s: strict PM order enforced\n", getName());
+                       fStrictTreeOrder = true;
+               }
+
+               if (rootDomain) {
+                       rootDomain->joinAggressiveness( child );
+               }
+       } else {
+               PM_LOG("%s: addPowerChild3 not in power plane\n", getName());
+       }
+
+       connection->release();
+}
 
+#ifndef __LP64__
 //*********************************************************************************
-// setPowerParent
+// [deprecated] setPowerParent
 //
 // Power Management is informing us who our parent is.
 // If we have a controlling driver, find out, given our newly-informed
 // power domain state, what state it would be in, and then tell it
 // to assume that state.
 //*********************************************************************************
-IOReturn IOService::setPowerParent ( IOPowerConnection * theParent, bool stateKnown, IOPMPowerFlags currentState )
-{
-    OSIterator *                       iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-    unsigned long              tempDesire;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogSetParent,stateKnown,currentState);
-    
-    IOLockLock(pm_vars->parentLock);
-    
-    if ( stateKnown && ((pm_vars->PMworkloop == NULL) || (pm_vars->PMcommandGate == NULL)) ) 
-    {
-        // we have a path to the root
-        // find out the workloop
-        getPMworkloop();
-        if ( pm_vars->PMworkloop != NULL ) 
-        {
-            if ( pm_vars->PMcommandGate == NULL ) 
-            {  
-                // and make our command gate
-                pm_vars->PMcommandGate = IOCommandGate::commandGate((OSObject *)this);
-                if ( pm_vars->PMcommandGate != NULL ) 
-                {
-                    pm_vars->PMworkloop->addEventSource(pm_vars->PMcommandGate);
-                }
-            }
-        }
-    }
-    
-    IOLockUnlock(pm_vars->parentLock);
-
-    // set our connection data
-    theParent->setParentCurrentPowerFlags(currentState);       
-    theParent->setParentKnowsState(stateKnown);
-
-    // combine parent knowledge
-    pm_vars->parentsKnowState = true;                          
-    pm_vars->parentsCurrentPowerFlags = 0;
-    
-    iter = getParentIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                pm_vars->parentsKnowState &= connection->parentKnowsState();
-                pm_vars->parentsCurrentPowerFlags |= connection->parentCurrentPowerFlags();
-            }
-        }
-        iter->release();
-    }
-    
-    if ( (pm_vars->theControllingDriver != NULL) &&
-         (pm_vars->parentsKnowState) ) 
-    {
-        pm_vars->maxCapability = pm_vars->theControllingDriver->maxCapabilityForDomainState(pm_vars->parentsCurrentPowerFlags);
-        // initially change into the state we are already in
-        tempDesire = priv->deviceDesire;                       
-        priv->deviceDesire = pm_vars->theControllingDriver->initialPowerStateForDomainState(pm_vars->parentsCurrentPowerFlags);
-        computeDesiredState();
-        priv->previousRequest = 0xffffffff;
-        changeState();
-        // put this back like before
-        priv->deviceDesire = tempDesire;    
-    }
-    
-   return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// addPowerChild
+
+IOReturn
+IOService::setPowerParent(
+       IOPowerConnection * theParent, bool stateKnown, IOPMPowerFlags powerFlags )
+{
+       return kIOReturnUnsupported;
+}
+#endif /* !__LP64__ */
+
+//*********************************************************************************
+// [public] removePowerChild
 //
-// Power Management is informing us who our children are.
+// Called on a parent whose child is being removed by PMstop().
+//*********************************************************************************
+
+IOReturn
+IOService::removePowerChild( IOPowerConnection * theNub )
+{
+       IORegistryEntry *   theChild;
+
+       PM_ASSERT_IN_GATE();
+       OUR_PMLog( kPMLogRemoveChild, 0, 0 );
+
+       theNub->retain();
+
+       // detach nub from child
+       theChild = theNub->copyChildEntry(gIOPowerPlane);
+       if (theChild) {
+               theNub->detachFromChild(theChild, gIOPowerPlane);
+               theChild->release();
+       }
+       // detach from the nub
+       detachFromChild(theNub, gIOPowerPlane);
+
+       // Are we awaiting an ack from this child?
+       if (theNub->getAwaitingAck()) {
+               // yes, pretend we got one
+               theNub->setAwaitingAck(false);
+               if (fHeadNotePendingAcks != 0) {
+                       // that's one fewer ack to worry about
+                       fHeadNotePendingAcks--;
+
+                       // is that the last?
+                       if (fHeadNotePendingAcks == 0) {
+                               stop_ack_timer();
+                               getPMRootDomain()->reset_watchdog_timer(this, 0);
+
+                               // This parent may have a request in the work queue that is
+                               // blocked on fHeadNotePendingAcks=0. And removePowerChild()
+                               // is called while executing the child's PMstop request so they
+                               // can occur simultaneously. IOPMWorkQueue::checkForWork() must
+                               // restart and check all request queues again.
+
+                               gIOPMWorkQueue->incrementProducerCount();
+                       }
+               }
+       }
+
+       theNub->release();
+
+       // A child has gone away, re-scan children desires and clamp bits.
+       // The fPendingAdjustPowerRequest helps to reduce redundant parent work.
+
+       if (!fAdjustPowerScheduled) {
+               IOPMRequest * request;
+               request = acquirePMRequest( this, kIOPMRequestTypeAdjustPowerState );
+               if (request) {
+                       submitPMRequest( request );
+                       fAdjustPowerScheduled = true;
+               }
+       }
+
+       return IOPMNoErr;
+}
+
 //*********************************************************************************
-IOReturn IOService::addPowerChild ( IOService * theChild )
-{
-    IOPowerConnection                       *connection;
-    unsigned int                            i;
-
-    if ( ! initialized ) 
-    {
-        // we're not a power-managed IOService
-        return IOPMNotYetInitialized;  
-    }
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAddChild,0,0);
-
-    // Put ourselves into a usable power state.
-    // We must be in an "on" power state, as our children must be able to access
-    // our hardware after joining the power plane.
-    makeUsable();
-    
-    // make a nub
-    connection = new IOPowerConnection;                        
-
-    connection->init();
-    connection->start(this);
-    connection->setAwaitingAck(false);
-    
-    // connect it up
-    attachToChild( connection,gIOPowerPlane );                 
-    connection->attachToChild( theChild,gIOPowerPlane );
-    connection->release();
-    
-    // tell it the current state of the power domain
-    if ( (pm_vars->theControllingDriver == NULL) ||            
-            ! (inPlane(gIOPowerPlane)) ||
-            ! (pm_vars->parentsKnowState) ) 
-    {
-        theChild->setPowerParent(connection,false,0);
-        if ( inPlane(gIOPowerPlane) ) 
-        {
-            for (i = 0; i <= kMaxType; i++) {
-                if ( pm_vars->current_aggressiveness_valid[i] ) 
-                {
-                    theChild->setAggressiveness (i, pm_vars->current_aggressiveness_values[i]);
-                }
-            }
-        }
-    } else {
-        theChild->setPowerParent(connection,true,pm_vars->thePowerStates[pm_vars->myCurrentState].outputPowerCharacter);
-        for (i = 0; i <= kMaxType; i++) 
-        {
-            if ( pm_vars->current_aggressiveness_valid[i] )
-            {
-                theChild->setAggressiveness (i, pm_vars->current_aggressiveness_values[i]);
-            }
-        }
-        // catch it up if change is in progress
-        add_child_to_active_change(connection);                                                        
-    }
-    
-    return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// removePowerChild
-//
-//*********************************************************************************
-IOReturn IOService::removePowerChild ( IOPowerConnection * theNub )
-{
-    IORegistryEntry                         *theChild;
-    OSIterator                              *iter;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogRemoveChild,0,0);
-
-    theNub->retain();
-    
-    // detach nub from child
-    theChild = theNub->copyChildEntry(gIOPowerPlane);                  
-    if ( theChild ) 
-    {
-        theNub->detachFromChild(theChild, gIOPowerPlane);
-        theChild->release();
-    }
-    // detach from the nub
-    detachFromChild(theNub,gIOPowerPlane);                             
-    
-    // are we awaiting an ack from this child?
-    if ( theNub->getAwaitingAck() ) 
-    {
-        // yes, pretend we got one
-        theNub->setAwaitingAck(false);
-        if ( acquire_lock() ) 
-        {
-            if (priv->head_note_pendingAcks != 0 ) 
-            {
-                // that's one fewer ack to worry about
-                priv->head_note_pendingAcks -= 1;
-                // is that the last?
-                if ( priv->head_note_pendingAcks == 0 ) 
-                {
-                    // yes, stop the timer
-                    stop_ack_timer();
-                    IOUnlock(priv->our_lock);
-                    // and now we can continue our power change
-                    all_acked();
-                } else {
-                    IOUnlock(priv->our_lock);
-                }
-            } else {
-                IOUnlock(priv->our_lock);
-            }
-        }
-    }
-
-    theNub->release();
-
-    // if not fully initialized
-    if ( (pm_vars->theControllingDriver == NULL) ||
-                !(inPlane(gIOPowerPlane)) ||
-                !(pm_vars->parentsKnowState) ) 
-    {
-        // we can do no more
-        return IOPMNoErr;                              
-    }
-
-    // Perhaps the departing child was holding up idle or system sleep - we need to re-evaluate our
-    // childrens' requests. Clear and re-calculate our kIOPMChildClamp and kIOPMChildClamp2 bits.
-    rebuildChildClampBits();
-    
-    if(!priv->clampOn)
-    {
-        // count children
-        iter = getChildIterator(gIOPowerPlane);
-        if ( !iter || !iter->getNextObject()  ) 
-        {
-            // paired to match the makeUsable() call in addPowerChild()
-            changePowerStateToPriv(0);
-        }
-        if(iter) iter->release();
-    }
-    
-    // this may be different now
-    computeDesiredState();
-    // change state if we can now tolerate lower power
-    changeState();
-
-    return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// registerPowerDriver
+// [public] registerPowerDriver
 //
 // A driver has called us volunteering to control power to our device.
-// If the power state array it provides is richer than the one we already
-// know about (supplied by an earlier volunteer), then accept the offer.
-// Notify all interested parties of our power state, which we now know.
-//*********************************************************************************
-
-IOReturn IOService::registerPowerDriver ( IOService * controllingDriver, IOPMPowerState* powerStates, unsigned long numberOfStates  )
-{
-    unsigned long                           i;
-    unsigned long                           tempDesire;
-
-    if ( (numberOfStates > pm_vars->theNumberOfPowerStates) 
-                    && (numberOfStates > 1) ) 
-    {
-        if (  priv->changeList->currentChange() == -1 ) 
-        {
-            if ( controllingDriver != NULL ) 
-            {
-                if ( numberOfStates <= IOPMMaxPowerStates ) 
-                {
-                    switch ( powerStates[0].version  ) 
-                    {
-                        case 1:
-                            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogControllingDriver,
-                                            (unsigned long)numberOfStates, (unsigned long)powerStates[0].version);
-                            for ( i = 0; i < numberOfStates; i++ ) 
-                            {
-                                pm_vars->thePowerStates[i] = powerStates[i];
-                            }
-                                break;
-                        case 2:
-                            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogControllingDriver,
-                                            (unsigned long) numberOfStates,(unsigned long) powerStates[0].version);
-                            for ( i = 0; i < numberOfStates; i++ ) 
-                            {
-                                pm_vars->thePowerStates[i].version = powerStates[i].version;
-                                pm_vars->thePowerStates[i].capabilityFlags = powerStates[i].capabilityFlags;
-                                pm_vars->thePowerStates[i].outputPowerCharacter = powerStates[i].outputPowerCharacter;
-                                pm_vars->thePowerStates[i].inputPowerRequirement = powerStates[i].inputPowerRequirement;
-                                pm_vars->thePowerStates[i].staticPower = powerStates[i].staticPower;
-                                pm_vars->thePowerStates[i].unbudgetedPower = powerStates[i].unbudgetedPower;
-                                pm_vars->thePowerStates[i].powerToAttain = powerStates[i].powerToAttain;
-                                pm_vars->thePowerStates[i].timeToAttain = powerStates[i].timeToAttain;
-                                pm_vars->thePowerStates[i].settleUpTime = powerStates[i].settleUpTime;
-                                pm_vars->thePowerStates[i].timeToLower = powerStates[i].timeToLower;
-                                pm_vars->thePowerStates[i].settleDownTime = powerStates[i].settleDownTime;
-                                pm_vars->thePowerStates[i].powerDomainBudget = powerStates[i].powerDomainBudget;
-                            }
-                                break;
-                        default:
-                            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogControllingDriverErr1,
-                                                                    (unsigned long)powerStates[0].version,0);
-                            return IOPMNoErr;
-                    }
-
-                    // make a mask of all the character bits we know about
-                    pm_vars->myCharacterFlags = 0;     
-                    for ( i = 0; i < numberOfStates; i++ ) {
-                        pm_vars->myCharacterFlags |= pm_vars->thePowerStates[i].outputPowerCharacter;
-                    }
-                    
-                   pm_vars->theNumberOfPowerStates = numberOfStates;
-                    pm_vars->theControllingDriver = controllingDriver;
-                    if ( priv->interestedDrivers->findItem(controllingDriver) == NULL ) 
-                    {
-                        // register it as interested, unless already done
-                        registerInterestedDriver (controllingDriver );
-                    }
-                    if ( priv->need_to_become_usable ) {
-                        priv->need_to_become_usable = false;
-                        priv->deviceDesire = pm_vars->theNumberOfPowerStates - 1;
-                    }
-
-                    if ( inPlane(gIOPowerPlane) &&
-                         (pm_vars->parentsKnowState) ) {
-                        pm_vars->maxCapability = pm_vars->theControllingDriver->maxCapabilityForDomainState(pm_vars->parentsCurrentPowerFlags);
-                        // initially change into the state we are already in
-                        tempDesire = priv->deviceDesire;
-                        priv->deviceDesire = pm_vars->theControllingDriver->initialPowerStateForDomainState(pm_vars->parentsCurrentPowerFlags);
-                        computeDesiredState();
-                        changeState();
-                        // put this back like before
-                        priv->deviceDesire = tempDesire;
-                    }
-                } else {
-                    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogControllingDriverErr2,(unsigned long)numberOfStates,0);
-                }
-            } else {
-                pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogControllingDriverErr4,0,0);
-            }
-        }
-    }
-    else {
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogControllingDriverErr5,(unsigned long)numberOfStates,0);
-    }
-    return IOPMNoErr;
-}
-
-//*********************************************************************************
-// registerInterestedDriver
+//*********************************************************************************
+
+IOReturn
+IOService::registerPowerDriver(
+       IOService *         powerDriver,
+       IOPMPowerState *    powerStates,
+       unsigned long       numberOfStates )
+{
+       IOPMRequest *       request;
+       IOPMPSEntry *       powerStatesCopy = NULL;
+       IOPMPowerStateIndex stateOrder;
+       IOReturn            error = kIOReturnSuccess;
+
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       if (!powerStates || (numberOfStates < 2)) {
+               OUR_PMLog(kPMLogControllingDriverErr5, numberOfStates, 0);
+               return kIOReturnBadArgument;
+       }
+
+       if (!powerDriver || !powerDriver->initialized) {
+               OUR_PMLog(kPMLogControllingDriverErr4, 0, 0);
+               return kIOReturnBadArgument;
+       }
+
+       if (powerStates[0].version > kIOPMPowerStateVersion2) {
+               OUR_PMLog(kPMLogControllingDriverErr1, powerStates[0].version, 0);
+               return kIOReturnBadArgument;
+       }
+
+       do {
+               // Make a copy of the supplied power state array.
+               powerStatesCopy = IONew(IOPMPSEntry, numberOfStates);
+               if (!powerStatesCopy) {
+                       error = kIOReturnNoMemory;
+                       break;
+               }
+
+               // Initialize to bogus values
+               for (IOPMPowerStateIndex i = 0; i < numberOfStates; i++) {
+                       powerStatesCopy[i].stateOrderToIndex = kIOPMPowerStateMax;
+               }
+
+               for (uint32_t i = 0; i < numberOfStates; i++) {
+                       powerStatesCopy[i].capabilityFlags  = powerStates[i].capabilityFlags;
+                       powerStatesCopy[i].outputPowerFlags = powerStates[i].outputPowerCharacter;
+                       powerStatesCopy[i].inputPowerFlags  = powerStates[i].inputPowerRequirement;
+                       powerStatesCopy[i].staticPower      = powerStates[i].staticPower;
+                       powerStatesCopy[i].settleUpTime     = powerStates[i].settleUpTime;
+                       powerStatesCopy[i].settleDownTime   = powerStates[i].settleDownTime;
+                       if (powerStates[i].version >= kIOPMPowerStateVersion2) {
+                               stateOrder = powerStates[i].stateOrder;
+                       } else {
+                               stateOrder = i;
+                       }
+
+                       if (stateOrder < numberOfStates) {
+                               powerStatesCopy[i].stateOrder = stateOrder;
+                               powerStatesCopy[stateOrder].stateOrderToIndex = i;
+                       }
+               }
+
+               for (IOPMPowerStateIndex i = 0; i < numberOfStates; i++) {
+                       if (powerStatesCopy[i].stateOrderToIndex == kIOPMPowerStateMax) {
+                               // power state order missing
+                               error = kIOReturnBadArgument;
+                               break;
+                       }
+               }
+               if (kIOReturnSuccess != error) {
+                       break;
+               }
+
+               request = acquirePMRequest( this, kIOPMRequestTypeRegisterPowerDriver );
+               if (!request) {
+                       error = kIOReturnNoMemory;
+                       break;
+               }
+
+               powerDriver->retain();
+               request->fArg0 = (void *) powerDriver;
+               request->fArg1 = (void *) powerStatesCopy;
+               request->fArg2 = (void *) numberOfStates;
+
+               submitPMRequest( request );
+               return kIOReturnSuccess;
+       }while (false);
+
+       if (powerStatesCopy) {
+               IODelete(powerStatesCopy, IOPMPSEntry, numberOfStates);
+       }
+
+       return error;
+}
+
+//*********************************************************************************
+// [private] handleRegisterPowerDriver
+//*********************************************************************************
+
+void
+IOService::handleRegisterPowerDriver( IOPMRequest * request )
+{
+       IOService *     powerDriver    = (IOService *)   request->fArg0;
+       IOPMPSEntry *   powerStates    = (IOPMPSEntry *) request->fArg1;
+       unsigned long   numberOfStates = (unsigned long) request->fArg2;
+       unsigned long   i, stateIndex;
+       unsigned long   lowestPowerState;
+       IOService *     root;
+       OSIterator *    iter;
+
+       PM_ASSERT_IN_GATE();
+       assert(powerStates);
+       assert(powerDriver);
+       assert(numberOfStates > 1);
+
+       if (!fNumberOfPowerStates) {
+               OUR_PMLog(kPMLogControllingDriver,
+                   (unsigned long) numberOfStates,
+                   (unsigned long) kIOPMPowerStateVersion1);
+
+               fPowerStates            = powerStates;
+               fNumberOfPowerStates    = numberOfStates;
+               fControllingDriver      = powerDriver;
+               fCurrentCapabilityFlags = fPowerStates[0].capabilityFlags;
+
+               lowestPowerState   = fPowerStates[0].stateOrderToIndex;
+               fHighestPowerState = fPowerStates[numberOfStates - 1].stateOrderToIndex;
+
+#if !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146))
+               {
+                       uint32_t        aotFlags;
+                       IOService *     service;
+                       OSObject *      object;
+                       OSData *        data;
+
+                       // Disallow kIOPMAOTPower states unless device tree enabled
+
+                       aotFlags = 0;
+                       service  = this;
+                       while (service && !service->inPlane(gIODTPlane)) {
+                               service = service->getProvider();
+                       }
+                       if (service) {
+                               object = service->copyProperty(kIOPMAOTPowerKey, gIODTPlane);
+                               data = OSDynamicCast(OSData, object);
+                               if (data && (data->getLength() >= sizeof(uint32_t))) {
+                                       aotFlags = ((uint32_t *)data->getBytesNoCopy())[0];
+                               }
+                               OSSafeReleaseNULL(object);
+                       }
+                       if (!aotFlags) {
+                               for (i = 0; i < numberOfStates; i++) {
+                                       if (kIOPMAOTPower & fPowerStates[i].inputPowerFlags) {
+                                               fPowerStates[i].inputPowerFlags  = 0xFFFFFFFF;
+                                               fPowerStates[i].capabilityFlags  = 0;
+                                               fPowerStates[i].outputPowerFlags = 0;
+                                       }
+                               }
+                       }
+               }
+#endif /* !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+
+               // OR'in all the output power flags
+               fMergedOutputPowerFlags = 0;
+               fDeviceUsablePowerState = lowestPowerState;
+               for (i = 0; i < numberOfStates; i++) {
+                       fMergedOutputPowerFlags |= fPowerStates[i].outputPowerFlags;
+
+                       stateIndex = fPowerStates[i].stateOrderToIndex;
+                       assert(stateIndex < numberOfStates);
+                       if ((fDeviceUsablePowerState == lowestPowerState) &&
+                           (fPowerStates[stateIndex].capabilityFlags & IOPMDeviceUsable)) {
+                               // The minimum power state that the device is usable
+                               fDeviceUsablePowerState = stateIndex;
+                       }
+               }
+
+               // Register powerDriver as interested, unless already done.
+               // We don't want to register the default implementation since
+               // it does nothing. One ramification of not always registering
+               // is the one fewer retain count held.
+
+               root = getPlatform()->getProvider();
+               assert(root);
+               if (!root ||
+                   ((OSMemberFunctionCast(void (*)(void),
+                   root, &IOService::powerStateDidChangeTo)) !=
+                   ((OSMemberFunctionCast(void (*)(void),
+                   this, &IOService::powerStateDidChangeTo)))) ||
+                   ((OSMemberFunctionCast(void (*)(void),
+                   root, &IOService::powerStateWillChangeTo)) !=
+                   ((OSMemberFunctionCast(void (*)(void),
+                   this, &IOService::powerStateWillChangeTo))))) {
+                       if (fInterestedDrivers->findItem(powerDriver) == NULL) {
+                               PM_LOCK();
+                               fInterestedDrivers->appendNewInformee(powerDriver);
+                               PM_UNLOCK();
+                       }
+               }
+
+               // Examine all existing power clients and perform limit check.
+
+               if (fPowerClients &&
+                   (iter = OSCollectionIterator::withCollection(fPowerClients))) {
+                       const OSSymbol * client;
+                       while ((client = (const OSSymbol *) iter->getNextObject())) {
+                               IOPMPowerStateIndex powerState = getPowerStateForClient(client);
+                               if (powerState >= numberOfStates) {
+                                       updatePowerClient(client, fHighestPowerState);
+                               }
+                       }
+                       iter->release();
+               }
+
+               if (inPlane(gIOPowerPlane) && fParentsKnowState) {
+                       IOPMPowerStateIndex tempDesire;
+                       fMaxPowerState = fControllingDriver->maxCapabilityForDomainState(fParentsCurrentPowerFlags);
+                       // initially change into the state we are already in
+                       tempDesire = fControllingDriver->initialPowerStateForDomainState(fParentsCurrentPowerFlags);
+                       adjustPowerState(tempDesire);
+               }
+       } else {
+               OUR_PMLog(kPMLogControllingDriverErr2, numberOfStates, 0);
+               IODelete(powerStates, IOPMPSEntry, numberOfStates);
+       }
+
+       powerDriver->release();
+}
+
+//*********************************************************************************
+// [public] registerInterestedDriver
 //
 // Add the caller to our list of interested drivers and return our current
 // power state.  If we don't have a power-controlling driver yet, we will
@@ -850,3975 +1332,7652 @@ IOReturn IOService::registerPowerDriver ( IOService * controllingDriver, IOPMPow
 // out what the current power state of the device is.
 //*********************************************************************************
 
-IOPMPowerFlags IOService::registerInterestedDriver ( IOService * theDriver )
+IOPMPowerFlags
+IOService::registerInterestedDriver( IOService * driver )
+{
+       IOPMRequest *   request;
+       bool            signal;
+
+       if (!driver || !initialized || !fInterestedDrivers) {
+               return 0;
+       }
+
+       PM_LOCK();
+       signal = (!fInsertInterestSet && !fRemoveInterestSet);
+       if (fInsertInterestSet == NULL) {
+               fInsertInterestSet = OSSet::withCapacity(4);
+       }
+       if (fInsertInterestSet) {
+               fInsertInterestSet->setObject(driver);
+               if (fRemoveInterestSet) {
+                       fRemoveInterestSet->removeObject(driver);
+               }
+       }
+       PM_UNLOCK();
+
+       if (signal) {
+               request = acquirePMRequest( this, kIOPMRequestTypeInterestChanged );
+               if (request) {
+                       submitPMRequest( request );
+               }
+       }
+
+       // This return value cannot be trusted, but return a value
+       // for those clients that care.
+
+       OUR_PMLog(kPMLogInterestedDriver, kIOPMDeviceUsable, 2);
+       return kIOPMDeviceUsable;
+}
+
+//*********************************************************************************
+// [public] deRegisterInterestedDriver
+//*********************************************************************************
+
+IOReturn
+IOService::deRegisterInterestedDriver( IOService * driver )
+{
+       IOPMinformee *      item;
+       IOPMRequest *       request;
+       bool                signal;
+
+       if (!driver) {
+               return kIOReturnBadArgument;
+       }
+       if (!initialized || !fInterestedDrivers) {
+               return IOPMNotPowerManaged;
+       }
+
+       PM_LOCK();
+       if (fInsertInterestSet) {
+               fInsertInterestSet->removeObject(driver);
+       }
+
+       item = fInterestedDrivers->findItem(driver);
+       if (!item) {
+               PM_UNLOCK();
+               return kIOReturnNotFound;
+       }
+
+       signal = (!fRemoveInterestSet && !fInsertInterestSet);
+       if (fRemoveInterestSet == NULL) {
+               fRemoveInterestSet = OSSet::withCapacity(4);
+       }
+       if (fRemoveInterestSet) {
+               fRemoveInterestSet->setObject(driver);
+               if (item->active) {
+                       item->active = false;
+                       waitForPMDriverCall( driver );
+               }
+       }
+       PM_UNLOCK();
+
+       if (signal) {
+               request = acquirePMRequest( this, kIOPMRequestTypeInterestChanged );
+               if (request) {
+                       submitPMRequest( request );
+               }
+       }
+
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [private] handleInterestChanged
+//
+// Handle interest added or removed.
+//*********************************************************************************
+
+void
+IOService::handleInterestChanged( IOPMRequest * request )
+{
+       IOService *         driver;
+       IOPMinformee *      informee;
+       IOPMinformeeList *  list = fInterestedDrivers;
+
+       PM_LOCK();
+
+       if (fInsertInterestSet) {
+               while ((driver = (IOService *) fInsertInterestSet->getAnyObject())) {
+                       if (list->findItem(driver) == NULL) {
+                               informee = list->appendNewInformee(driver);
+                       }
+                       fInsertInterestSet->removeObject(driver);
+               }
+               fInsertInterestSet->release();
+               fInsertInterestSet = NULL;
+       }
+
+       if (fRemoveInterestSet) {
+               while ((driver = (IOService *) fRemoveInterestSet->getAnyObject())) {
+                       informee = list->findItem(driver);
+                       if (informee) {
+                               // Clean-up async interest acknowledgement
+                               if (fHeadNotePendingAcks && informee->timer) {
+                                       informee->timer = 0;
+                                       fHeadNotePendingAcks--;
+                               }
+                               list->removeFromList(driver);
+                       }
+                       fRemoveInterestSet->removeObject(driver);
+               }
+               fRemoveInterestSet->release();
+               fRemoveInterestSet = NULL;
+       }
+
+       PM_UNLOCK();
+}
+
+//*********************************************************************************
+// [public] acknowledgePowerChange
+//
+// After we notified one of the interested drivers or a power-domain child
+// of an impending change in power, it has called to say it is now
+// prepared for the change.  If this object is the last to
+// acknowledge this change, we take whatever action we have been waiting
+// for.
+// That may include acknowledging to our parent.  In this case, we do it
+// last of all to insure that this doesn't cause the parent to call us some-
+// where else and alter data we are relying on here (like the very existance
+// of a "current change note".)
+//*********************************************************************************
+
+IOReturn
+IOService::acknowledgePowerChange( IOService * whichObject )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+       if (!whichObject) {
+               return kIOReturnBadArgument;
+       }
+
+       request = acquirePMRequest( this, kIOPMRequestTypeAckPowerChange );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       whichObject->retain();
+       request->fArg0 = whichObject;
+
+       submitPMRequest( request );
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [private] handleAcknowledgePowerChange
+//*********************************************************************************
+
+bool
+IOService::handleAcknowledgePowerChange( IOPMRequest * request )
+{
+       IOPMinformee *      informee;
+       unsigned long       childPower = kIOPMUnknown;
+       IOService *         theChild;
+       IOService *         whichObject;
+       bool                all_acked  = false;
+
+       PM_ASSERT_IN_GATE();
+       whichObject = (IOService *) request->fArg0;
+       assert(whichObject);
+
+       // one of our interested drivers?
+       informee = fInterestedDrivers->findItem( whichObject );
+       if (informee == NULL) {
+               if (!isChild(whichObject, gIOPowerPlane)) {
+                       OUR_PMLog(kPMLogAcknowledgeErr1, 0, 0);
+                       goto no_err;
+               } else {
+                       OUR_PMLog(kPMLogChildAcknowledge, fHeadNotePendingAcks, 0);
+               }
+       } else {
+               OUR_PMLog(kPMLogDriverAcknowledge, fHeadNotePendingAcks, 0);
+       }
+
+       if (fHeadNotePendingAcks != 0) {
+               assert(fPowerStates != NULL);
+
+               // yes, make sure we're expecting acks
+               if (informee != NULL) {
+                       // it's an interested driver
+                       // make sure we're expecting this ack
+                       if (informee->timer != 0) {
+                               if (informee->timer > 0) {
+                                       uint64_t nsec = computeTimeDeltaNS(&informee->startTime);
+                                       if (nsec > LOG_SETPOWER_TIMES) {
+                                               getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                                       gIOPMStatsDriverPSChangeSlow, informee->whatObject->getName(),
+                                                       fDriverCallReason, NS_TO_MS(nsec), informee->whatObject->getRegistryEntryID(),
+                                                       NULL, fHeadNotePowerState);
+                                       }
+                               }
+
+                               // mark it acked
+                               informee->timer = 0;
+                               // that's one fewer to worry about
+                               fHeadNotePendingAcks--;
+                       } else {
+                               // this driver has already acked
+                               OUR_PMLog(kPMLogAcknowledgeErr2, 0, 0);
+                       }
+               } else {
+                       // it's a child
+                       // make sure we're expecting this ack
+                       if (((IOPowerConnection *)whichObject)->getAwaitingAck()) {
+                               // that's one fewer to worry about
+                               fHeadNotePendingAcks--;
+                               ((IOPowerConnection *)whichObject)->setAwaitingAck(false);
+                               theChild = (IOService *)whichObject->copyChildEntry(gIOPowerPlane);
+                               if (theChild) {
+                                       childPower = theChild->currentPowerConsumption();
+                                       theChild->release();
+                               }
+                               if (childPower == kIOPMUnknown) {
+                                       fHeadNotePowerArrayEntry->staticPower = kIOPMUnknown;
+                               } else {
+                                       if (fHeadNotePowerArrayEntry->staticPower != kIOPMUnknown) {
+                                               fHeadNotePowerArrayEntry->staticPower += childPower;
+                                       }
+                               }
+                       }
+               }
+
+               if (fHeadNotePendingAcks == 0) {
+                       // yes, stop the timer
+                       stop_ack_timer();
+                       // and now we can continue
+                       all_acked = true;
+                       getPMRootDomain()->reset_watchdog_timer(this, 0);
+               }
+       } else {
+               OUR_PMLog(kPMLogAcknowledgeErr3, 0, 0); // not expecting anybody to ack
+       }
+
+no_err:
+       if (whichObject) {
+               whichObject->release();
+       }
+
+       return all_acked;
+}
+
+//*********************************************************************************
+// [public] acknowledgeSetPowerState
+//
+// After we instructed our controlling driver to change power states,
+// it has called to say it has finished doing so.
+// We continue to process the power state change.
+//*********************************************************************************
+
+IOReturn
+IOService::acknowledgeSetPowerState( void )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       request = acquirePMRequest( this, kIOPMRequestTypeAckSetPowerState );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       submitPMRequest( request );
+       return kIOReturnSuccess;
+}
+
+//*********************************************************************************
+// [private] adjustPowerState
+//*********************************************************************************
+
+void
+IOService::adjustPowerState( uint32_t clamp )
+{
+       PM_ASSERT_IN_GATE();
+       computeDesiredState(clamp, false);
+       if (fControllingDriver && fParentsKnowState && inPlane(gIOPowerPlane)) {
+               IOPMPowerChangeFlags changeFlags = kIOPMSelfInitiated;
+
+               // Indicate that children desires must be ignored, and do not ask
+               // apps for permission to drop power. This is used by root domain
+               // for demand sleep.
+
+               if (getPMRequestType() == kIOPMRequestTypeRequestPowerStateOverride) {
+                       changeFlags |= (kIOPMIgnoreChildren | kIOPMSkipAskPowerDown);
+               }
+
+               startPowerChange(
+                       /* flags        */ changeFlags,
+                       /* power state  */ fDesiredPowerState,
+                       /* domain flags */ 0,
+                       /* connection   */ NULL,
+                       /* parent flags */ 0);
+       }
+}
+
+//*********************************************************************************
+// [public] synchronizePowerTree
+//*********************************************************************************
+
+IOReturn
+IOService::synchronizePowerTree(
+       IOOptionBits    options,
+       IOService *     notifyRoot )
+{
+       IOPMRequest *   request_c = NULL;
+       IOPMRequest *   request_s;
+
+       if (this != getPMRootDomain()) {
+               return kIOReturnBadArgument;
+       }
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
+       }
+
+       OUR_PMLog(kPMLogCSynchronizePowerTree, options, (notifyRoot != NULL));
+
+       if (notifyRoot) {
+               IOPMRequest * nr;
+
+               // Cancels don't need to be synchronized.
+               nr = acquirePMRequest(notifyRoot, kIOPMRequestTypeChildNotifyDelayCancel);
+               if (nr) {
+                       submitPMRequest(nr);
+               }
+               nr = acquirePMRequest(getPMRootDomain(), kIOPMRequestTypeChildNotifyDelayCancel);
+               if (nr) {
+                       submitPMRequest(nr);
+               }
+       }
+
+       request_s = acquirePMRequest( this, kIOPMRequestTypeSynchronizePowerTree );
+       if (!request_s) {
+               goto error_no_memory;
+       }
+
+       if (options & kIOPMSyncCancelPowerDown) {
+               request_c = acquirePMRequest( this, kIOPMRequestTypeIdleCancel );
+       }
+       if (request_c) {
+               request_c->attachNextRequest( request_s );
+               submitPMRequest(request_c);
+       }
+
+       request_s->fArg0 = (void *)(uintptr_t) options;
+       submitPMRequest(request_s);
+
+       return kIOReturnSuccess;
+
+error_no_memory:
+       if (request_c) {
+               releasePMRequest(request_c);
+       }
+       if (request_s) {
+               releasePMRequest(request_s);
+       }
+       return kIOReturnNoMemory;
+}
+
+//*********************************************************************************
+// [private] handleSynchronizePowerTree
+//*********************************************************************************
+
+void
+IOService::handleSynchronizePowerTree( IOPMRequest * request )
+{
+       PM_ASSERT_IN_GATE();
+       if (fControllingDriver && fParentsKnowState && inPlane(gIOPowerPlane) &&
+           (fCurrentPowerState == fHighestPowerState)) {
+               IOOptionBits options = (uintptr_t) request->fArg0;
+
+               startPowerChange(
+                       /* flags        */ kIOPMSelfInitiated | kIOPMSynchronize |
+                       (options & kIOPMSyncNoChildNotify),
+                       /* power state  */ fCurrentPowerState,
+                       /* domain flags */ 0,
+                       /* connection   */ NULL,
+                       /* parent flags */ 0);
+       }
+}
+
+#ifndef __LP64__
+//*********************************************************************************
+// [deprecated] powerDomainWillChangeTo
+//
+// Called by the power-hierarchy parent notifying of a new power state
+// in the power domain.
+// We enqueue a parent power-change to our queue of power changes.
+// This may or may not cause us to change power, depending on what
+// kind of change is occuring in the domain.
+//*********************************************************************************
+
+IOReturn
+IOService::powerDomainWillChangeTo(
+       IOPMPowerFlags      newPowerFlags,
+       IOPowerConnection * whichParent )
+{
+       assert(false);
+       return kIOReturnUnsupported;
+}
+#endif /* !__LP64__ */
+
+//*********************************************************************************
+// [private] handlePowerDomainWillChangeTo
+//*********************************************************************************
+
+void
+IOService::handlePowerDomainWillChangeTo( IOPMRequest * request )
+{
+       IOPMPowerFlags       parentPowerFlags = (IOPMPowerFlags) request->fArg0;
+       IOPowerConnection *  whichParent = (IOPowerConnection *) request->fArg1;
+       IOPMPowerChangeFlags parentChangeFlags = (IOPMPowerChangeFlags)(uintptr_t) request->fArg2;
+       IOPMPowerChangeFlags myChangeFlags;
+       OSIterator *         iter;
+       OSObject *           next;
+       IOPowerConnection *  connection;
+       IOPMPowerStateIndex  maxPowerState;
+       IOPMPowerFlags       combinedPowerFlags;
+       bool                 savedParentsKnowState;
+       IOReturn             result = IOPMAckImplied;
+
+       PM_ASSERT_IN_GATE();
+       OUR_PMLog(kPMLogWillChange, parentPowerFlags, 0);
+
+       if (!inPlane(gIOPowerPlane) || !whichParent || !whichParent->getAwaitingAck()) {
+               PM_LOG("%s::%s not in power tree\n", getName(), __FUNCTION__);
+               goto exit_no_ack;
+       }
+
+       savedParentsKnowState = fParentsKnowState;
+
+       // Combine parents' output power flags.
+
+       combinedPowerFlags = 0;
+
+       iter = getParentIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((connection = OSDynamicCast(IOPowerConnection, next))) {
+                               if (connection == whichParent) {
+                                       combinedPowerFlags |= parentPowerFlags;
+                               } else {
+                                       combinedPowerFlags |= connection->parentCurrentPowerFlags();
+                               }
+                       }
+               }
+               iter->release();
+       }
+
+       // If our initial change has yet to occur, then defer the power change
+       // until after the power domain has completed its power transition.
+
+       if (fControllingDriver && !fInitialPowerChange) {
+               maxPowerState = fControllingDriver->maxCapabilityForDomainState(
+                       combinedPowerFlags);
+
+               if (parentChangeFlags & kIOPMDomainPowerDrop) {
+                       // fMaxPowerState set a limit on self-initiated power changes.
+                       // Update it before a parent power drop.
+                       fMaxPowerState = maxPowerState;
+               }
+
+               // Use kIOPMSynchronize below instead of kIOPMRootBroadcastFlags
+               // to avoid propagating the root change flags if any service must
+               // change power state due to root's will-change notification.
+               // Root does not change power state for kIOPMSynchronize.
+
+               myChangeFlags = kIOPMParentInitiated | kIOPMDomainWillChange |
+                   (parentChangeFlags & kIOPMSynchronize);
+
+               result = startPowerChange(
+                       /* flags        */ myChangeFlags,
+                       /* power state  */ maxPowerState,
+                       /* domain flags */ combinedPowerFlags,
+                       /* connection   */ whichParent,
+                       /* parent flags */ parentPowerFlags);
+       }
+
+       // If parent is dropping power, immediately update the parent's
+       // capability flags. Any future merging of parent(s) combined
+       // power flags should account for this power drop.
+
+       if (parentChangeFlags & kIOPMDomainPowerDrop) {
+               setParentInfo(parentPowerFlags, whichParent, true);
+       }
+
+       // Parent is expecting an ACK from us. If we did not embark on a state
+       // transition, i.e. startPowerChange() returned IOPMAckImplied. We are
+       // still required to issue an ACK to our parent.
+
+       if (IOPMAckImplied == result) {
+               IOService * parent;
+               parent = (IOService *) whichParent->copyParentEntry(gIOPowerPlane);
+               assert(parent);
+               if (parent) {
+                       parent->acknowledgePowerChange( whichParent );
+                       parent->release();
+               }
+       }
+
+exit_no_ack:
+       // Drop the retain from notifyChild().
+       if (whichParent) {
+               whichParent->release();
+       }
+}
+
+#ifndef __LP64__
+//*********************************************************************************
+// [deprecated] powerDomainDidChangeTo
+//
+// Called by the power-hierarchy parent after the power state of the power domain
+// has settled at a new level.
+// We enqueue a parent power-change to our queue of power changes.
+// This may or may not cause us to change power, depending on what
+// kind of change is occuring in the domain.
+//*********************************************************************************
+
+IOReturn
+IOService::powerDomainDidChangeTo(
+       IOPMPowerFlags      newPowerFlags,
+       IOPowerConnection * whichParent )
 {
-    IOPMinformee                            *newInformee;
-    IOPMPowerFlags                          futureCapability;
+       assert(false);
+       return kIOReturnUnsupported;
+}
+#endif /* !__LP64__ */
+
+//*********************************************************************************
+// [private] handlePowerDomainDidChangeTo
+//*********************************************************************************
 
-    if (theDriver == NULL ) {
-        return 0;
-    }
+void
+IOService::handlePowerDomainDidChangeTo( IOPMRequest * request )
+{
+       IOPMPowerFlags       parentPowerFlags = (IOPMPowerFlags) request->fArg0;
+       IOPowerConnection *  whichParent = (IOPowerConnection *) request->fArg1;
+       IOPMPowerChangeFlags parentChangeFlags = (IOPMPowerChangeFlags)(uintptr_t) request->fArg2;
+       IOPMPowerChangeFlags myChangeFlags;
+       IOPMPowerStateIndex  maxPowerState;
+       IOPMPowerStateIndex  initialDesire = kPowerStateZero;
+       bool                 computeDesire = false;
+       bool                 desireChanged = false;
+       bool                 savedParentsKnowState;
+       IOReturn             result = IOPMAckImplied;
+
+       PM_ASSERT_IN_GATE();
+       OUR_PMLog(kPMLogDidChange, parentPowerFlags, 0);
+
+       if (!inPlane(gIOPowerPlane) || !whichParent || !whichParent->getAwaitingAck()) {
+               PM_LOG("%s::%s not in power tree\n", getName(), __FUNCTION__);
+               goto exit_no_ack;
+       }
+
+       savedParentsKnowState = fParentsKnowState;
+
+       setParentInfo(parentPowerFlags, whichParent, true);
+
+       if (fControllingDriver) {
+               maxPowerState = fControllingDriver->maxCapabilityForDomainState(
+                       fParentsCurrentPowerFlags);
+
+               if ((parentChangeFlags & kIOPMDomainPowerDrop) == 0) {
+                       // fMaxPowerState set a limit on self-initiated power changes.
+                       // Update it after a parent power rise.
+                       fMaxPowerState = maxPowerState;
+               }
+
+               if (fInitialPowerChange) {
+                       computeDesire = true;
+                       initialDesire = fControllingDriver->initialPowerStateForDomainState(
+                               fParentsCurrentPowerFlags);
+               } else if (parentChangeFlags & kIOPMRootChangeUp) {
+                       if (fAdvisoryTickleUsed) {
+                               // On system wake, re-compute the desired power state since
+                               // gIOPMAdvisoryTickleEnabled will change for a full wake,
+                               // which is an input to computeDesiredState(). This is not
+                               // necessary for a dark wake because powerChangeDone() will
+                               // handle the dark to full wake case, but it does no harm.
+
+                               desireChanged = true;
+                       }
+
+                       if (fResetPowerStateOnWake) {
+                               // Query the driver for the desired power state on system wake.
+                               // Default implementation returns the lowest power state.
+
+                               IOPMPowerStateIndex wakePowerState =
+                                   fControllingDriver->initialPowerStateForDomainState(
+                                       kIOPMRootDomainState | kIOPMPowerOn );
+
+                               // fDesiredPowerState was adjusted before going to sleep
+                               // with fDeviceDesire at min.
+
+                               if (StateOrder(wakePowerState) > StateOrder(fDesiredPowerState)) {
+                                       // Must schedule a power adjustment if we changed the
+                                       // device desire. That will update the desired domain
+                                       // power on the parent power connection and ping the
+                                       // power parent if necessary.
+
+                                       updatePowerClient(gIOPMPowerClientDevice, wakePowerState);
+                                       desireChanged = true;
+                               }
+                       }
+               }
+
+               if (computeDesire || desireChanged) {
+                       computeDesiredState(initialDesire, false);
+               }
+
+               // Absorb and propagate parent's broadcast flags
+               myChangeFlags = kIOPMParentInitiated | kIOPMDomainDidChange |
+                   (parentChangeFlags & kIOPMRootBroadcastFlags);
+
+#if !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146))
+               if (kIOPMAOTPower & fPowerStates[maxPowerState].inputPowerFlags) {
+                       IOLog("aotPS %s0x%qx[%ld]\n", getName(), getRegistryEntryID(), maxPowerState);
+               }
+#endif /* !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+
+               result = startPowerChange(
+                       /* flags        */ myChangeFlags,
+                       /* power state  */ maxPowerState,
+                       /* domain flags */ fParentsCurrentPowerFlags,
+                       /* connection   */ whichParent,
+                       /* parent flags */ 0);
+       }
+
+       // Parent is expecting an ACK from us. If we did not embark on a state
+       // transition, i.e. startPowerChange() returned IOPMAckImplied. We are
+       // still required to issue an ACK to our parent.
+
+       if (IOPMAckImplied == result) {
+               IOService * parent;
+               parent = (IOService *) whichParent->copyParentEntry(gIOPowerPlane);
+               assert(parent);
+               if (parent) {
+                       parent->acknowledgePowerChange( whichParent );
+                       parent->release();
+               }
+       }
+
+       // If the parent registers its power driver late, then this is the
+       // first opportunity to tell our parent about our desire. Or if the
+       // child's desire changed during a parent change notify.
+
+       if (fControllingDriver &&
+           ((!savedParentsKnowState && fParentsKnowState) || desireChanged)) {
+               PM_LOG1("%s::powerDomainDidChangeTo parentsKnowState %d\n",
+                   getName(), fParentsKnowState);
+               requestDomainPower( fDesiredPowerState );
+       }
+
+exit_no_ack:
+       // Drop the retain from notifyChild().
+       if (whichParent) {
+               whichParent->release();
+       }
+}
 
-    // make new driver node
-    newInformee = new IOPMinformee;
-    newInformee->initialize(theDriver);
-    // add it to list of drivers
-    priv->interestedDrivers->addToList(newInformee);
+//*********************************************************************************
+// [private] setParentInfo
+//
+// Set our connection data for one specific parent, and then combine all the parent
+// data together.
+//*********************************************************************************
 
-    if ( (pm_vars->theControllingDriver == NULL) ||
-                    !(inPlane(gIOPowerPlane)) ||
-                    !(pm_vars->parentsKnowState) ) 
-    {
-        // can't tell it a state yet
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogInterestedDriver,IOPMNotPowerManaged,0);
-        return IOPMNotPowerManaged;
-    }
+void
+IOService::setParentInfo(
+       IOPMPowerFlags      newPowerFlags,
+       IOPowerConnection * whichParent,
+       bool                knowsState )
+{
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * conn;
+
+       PM_ASSERT_IN_GATE();
+
+       // set our connection data
+       whichParent->setParentCurrentPowerFlags(newPowerFlags);
+       whichParent->setParentKnowsState(knowsState);
+
+       // recompute our parent info
+       fParentsCurrentPowerFlags = 0;
+       fParentsKnowState = true;
+
+       iter = getParentIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((conn = OSDynamicCast(IOPowerConnection, next))) {
+                               fParentsKnowState &= conn->parentKnowsState();
+                               fParentsCurrentPowerFlags |= conn->parentCurrentPowerFlags();
+                       }
+               }
+               iter->release();
+       }
+}
 
-    // can we notify new driver of a change in progress?
-    switch (priv->machine_state) {
-        case kIOPM_OurChangeSetPowerState:
-        case kIOPM_OurChangeFinish:
-        case kIOPM_ParentDownSetPowerState_Delayed:
-        case kIOPM_ParentDownAcknowledgeChange_Delayed:
-        case kIOPM_ParentUpSetPowerState_Delayed:
-        case kIOPM_ParentUpAcknowledgePowerChange_Delayed:
-            // yes, remember what we tell it
-            futureCapability = priv->head_note_capabilityFlags;
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogInterestedDriver,(unsigned long)futureCapability,1);
-            // notify it
-            add_driver_to_active_change(newInformee);
-            // and return the same thing
-            return futureCapability;
-    }
+//******************************************************************************
+// [private] trackSystemSleepPreventers
+//******************************************************************************
 
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogInterestedDriver,
-                    (unsigned long) pm_vars->thePowerStates[pm_vars->myCurrentState].capabilityFlags,2);
+void
+IOService::trackSystemSleepPreventers(
+       IOPMPowerStateIndex     oldPowerState,
+       IOPMPowerStateIndex     newPowerState,
+       IOPMPowerChangeFlags    changeFlags __unused )
+{
+       IOPMPowerFlags  oldCapability, newCapability;
+
+       oldCapability = fPowerStates[oldPowerState].capabilityFlags &
+           (kIOPMPreventIdleSleep | kIOPMPreventSystemSleep);
+       newCapability = fPowerStates[newPowerState].capabilityFlags &
+           (kIOPMPreventIdleSleep | kIOPMPreventSystemSleep);
+
+       if (fHeadNoteChangeFlags & kIOPMInitialPowerChange) {
+               oldCapability = 0;
+       }
+       if (oldCapability == newCapability) {
+               return;
+       }
+
+       if ((oldCapability ^ newCapability) & kIOPMPreventIdleSleep) {
+               bool enablePrevention  = ((oldCapability & kIOPMPreventIdleSleep) == 0);
+               bool idleCancelAllowed = getPMRootDomain()->updatePreventIdleSleepList(
+                       this, enablePrevention);
+#if SUPPORT_IDLE_CANCEL
+               if (idleCancelAllowed && enablePrevention) {
+                       IOPMRequest *   cancelRequest;
+
+                       cancelRequest = acquirePMRequest( getPMRootDomain(), kIOPMRequestTypeIdleCancel );
+                       if (cancelRequest) {
+                               submitPMRequest( cancelRequest );
+                       }
+               }
+#endif
+       }
+
+       if ((oldCapability ^ newCapability) & kIOPMPreventSystemSleep) {
+               getPMRootDomain()->updatePreventSystemSleepList(this,
+                   ((oldCapability & kIOPMPreventSystemSleep) == 0));
+       }
+}
+
+//*********************************************************************************
+// [public] requestPowerDomainState
+//
+// Called on a power parent when a child's power requirement changes.
+//*********************************************************************************
+
+IOReturn
+IOService::requestPowerDomainState(
+       IOPMPowerFlags      childRequestPowerFlags,
+       IOPowerConnection * childConnection,
+       unsigned long       specification )
+{
+       IOPMPowerStateIndex order, powerState;
+       IOPMPowerFlags      outputPowerFlags;
+       IOService *         child;
+       IOPMRequest *       subRequest;
+       bool                adjustPower = false;
+
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       if (gIOPMWorkLoop->onThread() == false) {
+               PM_LOG("%s::requestPowerDomainState\n", getName());
+               return kIOReturnSuccess;
+       }
+
+       OUR_PMLog(kPMLogRequestDomain, childRequestPowerFlags, specification);
+
+       if (!isChild(childConnection, gIOPowerPlane)) {
+               return kIOReturnNotAttached;
+       }
+
+       if (!fControllingDriver || !fNumberOfPowerStates) {
+               return kIOReturnNotReady;
+       }
+
+       child = (IOService *) childConnection->getChildEntry(gIOPowerPlane);
+       assert(child);
+
+       // Remove flags from child request which we can't possibly supply
+       childRequestPowerFlags &= fMergedOutputPowerFlags;
+
+       // Merge in the power flags contributed by this power parent
+       // at its current or impending power state.
+
+       outputPowerFlags = fPowerStates[fCurrentPowerState].outputPowerFlags;
+       if (fMachineState != kIOPM_Finished) {
+               if (IS_POWER_DROP && !IS_ROOT_DOMAIN) {
+                       // Use the lower power state when dropping power.
+                       // Must be careful since a power drop can be cancelled
+                       // from the following states:
+                       // - kIOPM_OurChangeTellClientsPowerDown
+                       // - kIOPM_OurChangeTellPriorityClientsPowerDown
+                       //
+                       // The child must not wait for this parent to raise power
+                       // if the power drop was cancelled. The solution is to cancel
+                       // the power drop if possible, then schedule an adjustment to
+                       // re-evaluate the parent's power state.
+                       //
+                       // Root domain is excluded to avoid idle sleep issues. And allow
+                       // root domain children to pop up when system is going to sleep.
+
+                       if ((fMachineState == kIOPM_OurChangeTellClientsPowerDown) ||
+                           (fMachineState == kIOPM_OurChangeTellPriorityClientsPowerDown)) {
+                               fDoNotPowerDown = true; // cancel power drop
+                               adjustPower     = true;// schedule an adjustment
+                               PM_LOG1("%s: power drop cancelled in state %u by %s\n",
+                                   getName(), fMachineState, child->getName());
+                       } else {
+                               // Beyond cancellation point, report the impending state.
+                               outputPowerFlags =
+                                   fPowerStates[fHeadNotePowerState].outputPowerFlags;
+                       }
+               } else if (IS_POWER_RISE) {
+                       // When raising power, must report the output power flags from
+                       // child's perspective. A child power request may arrive while
+                       // parent is transitioning upwards. If a request arrives after
+                       // setParentInfo() has already recorded the output power flags
+                       // for the next power state, then using the power supplied by
+                       // fCurrentPowerState is incorrect, and might cause the child
+                       // to wait when it should not.
+
+                       outputPowerFlags = childConnection->parentCurrentPowerFlags();
+               }
+       }
+       child->fHeadNoteDomainTargetFlags |= outputPowerFlags;
+
+       // Map child's requested power flags to one of our power state.
+
+       for (order = 0; order < fNumberOfPowerStates; order++) {
+               powerState = fPowerStates[order].stateOrderToIndex;
+               if ((fPowerStates[powerState].outputPowerFlags & childRequestPowerFlags)
+                   == childRequestPowerFlags) {
+                       break;
+               }
+       }
+       if (order >= fNumberOfPowerStates) {
+               powerState = kPowerStateZero;
+       }
+
+       // Conditions that warrants a power adjustment on this parent.
+       // Adjust power will also propagate any changes to the child's
+       // prevent idle/sleep flags towards the root domain.
+
+       if (!childConnection->childHasRequestedPower() ||
+           (powerState != childConnection->getDesiredDomainState())) {
+               adjustPower = true;
+       }
+
+#if ENABLE_DEBUG_LOGS
+       if (adjustPower) {
+               PM_LOG("requestPowerDomainState[%s]: %s, init %d, %u->%u\n",
+                   getName(), child->getName(),
+                   !childConnection->childHasRequestedPower(),
+                   (uint32_t) childConnection->getDesiredDomainState(),
+                   (uint32_t) powerState);
+       }
+#endif
+
+       // Record the child's desires on the connection.
+       childConnection->setChildHasRequestedPower();
+       childConnection->setDesiredDomainState( powerState );
+
+       // Schedule a request to re-evaluate all children desires and
+       // adjust power state. Submit a request if one wasn't pending,
+       // or if the current request is part of a call tree.
+
+       if (adjustPower && !fDeviceOverrideEnabled &&
+           (!fAdjustPowerScheduled || gIOPMRequest->getRootRequest())) {
+               subRequest = acquirePMRequest(
+                       this, kIOPMRequestTypeAdjustPowerState, gIOPMRequest );
+               if (subRequest) {
+                       submitPMRequest( subRequest );
+                       fAdjustPowerScheduled = true;
+               }
+       }
+
+       return kIOReturnSuccess;
+}
+
+//*********************************************************************************
+// [public] temporaryPowerClampOn
+//
+// A power domain wants to clamp its power on till it has children which
+// will thendetermine the power domain state.
+//
+// We enter the highest state until addPowerChild is called.
+//*********************************************************************************
+
+IOReturn
+IOService::temporaryPowerClampOn( void )
+{
+       return requestPowerState( gIOPMPowerClientChildProxy, kIOPMPowerStateMax );
+}
+
+//*********************************************************************************
+// [public] makeUsable
+//
+// Some client of our device is asking that we become usable.  Although
+// this has not come from a subclassed device object, treat it exactly
+// as if it had.  In this way, subsequent requests for lower power from
+// a subclassed device object will pre-empt this request.
+//
+// We treat this as a subclass object request to switch to the
+// highest power state.
+//*********************************************************************************
+
+IOReturn
+IOService::makeUsable( void )
+{
+       OUR_PMLog(kPMLogMakeUsable, 0, 0);
+       return requestPowerState( gIOPMPowerClientDevice, kIOPMPowerStateMax );
+}
+
+//*********************************************************************************
+// [public] currentCapability
+//*********************************************************************************
+
+IOPMPowerFlags
+IOService::currentCapability( void )
+{
+       if (!initialized) {
+               return IOPMNotPowerManaged;
+       }
+
+       return fCurrentCapabilityFlags;
+}
+
+//*********************************************************************************
+// [public] changePowerStateTo
+//
+// Called by our power-controlling driver to change power state. The new desired
+// power state is computed and compared against the current power state. If those
+// power states differ, then a power state change is initiated.
+//*********************************************************************************
+
+IOReturn
+IOService::changePowerStateTo( unsigned long ordinal )
+{
+       OUR_PMLog(kPMLogChangeStateTo, ordinal, 0);
+       return requestPowerState( gIOPMPowerClientDriver, ordinal );
+}
+
+//*********************************************************************************
+// [protected] changePowerStateToPriv
+//
+// Called by our driver subclass to change power state. The new desired power
+// state is computed and compared against the current power state. If those
+// power states differ, then a power state change is initiated.
+//*********************************************************************************
+
+IOReturn
+IOService::changePowerStateToPriv( unsigned long ordinal )
+{
+       OUR_PMLog(kPMLogChangeStateToPriv, ordinal, 0);
+       return requestPowerState( gIOPMPowerClientDevice, ordinal );
+}
+
+//*********************************************************************************
+// [public] changePowerStateWithOverrideTo
+//
+// Called by our driver subclass to change power state. The new desired power
+// state is computed and compared against the current power state. If those
+// power states differ, then a power state change is initiated.
+// Override enforced - Children and Driver desires are ignored.
+//*********************************************************************************
+
+IOReturn
+IOService::changePowerStateWithOverrideTo( IOPMPowerStateIndex ordinal,
+    IOPMRequestTag tag )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
+       }
+
+       OUR_PMLog(kPMLogChangeStateToPriv, ordinal, 0);
+
+       request = acquirePMRequest( this, kIOPMRequestTypeRequestPowerStateOverride );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       gIOPMPowerClientDevice->retain();
+       request->fRequestTag = tag;
+       request->fArg0 = (void *) ordinal;
+       request->fArg1 = (void *) gIOPMPowerClientDevice;
+       request->fArg2 = NULL;
+#if NOT_READY
+       if (action) {
+               request->installCompletionAction( action, target, param );
+       }
+#endif
+
+       // Prevent needless downwards power transitions by clamping power
+       // until the scheduled request is executed.
+
+       if (gIOPMWorkLoop->inGate() && (ordinal < fNumberOfPowerStates)) {
+               fTempClampPowerState = StateMax(fTempClampPowerState, ordinal);
+               fTempClampCount++;
+               fOverrideMaxPowerState = ordinal;
+               request->fArg2 = (void *) (uintptr_t) true;
+       }
+
+       submitPMRequest( request );
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [public] changePowerStateForRootDomain
+//
+// Adjust the root domain's power desire on the target
+//*********************************************************************************
+
+IOReturn
+IOService::changePowerStateForRootDomain( IOPMPowerStateIndex ordinal )
+{
+       OUR_PMLog(kPMLogChangeStateForRootDomain, ordinal, 0);
+       return requestPowerState( gIOPMPowerClientRootDomain, ordinal );
+}
+
+//*********************************************************************************
+// [public for PMRD] quiescePowerTree
+//
+// For root domain to issue a request to quiesce the power tree.
+// Supplied callback invoked upon completion.
+//*********************************************************************************
+
+IOReturn
+IOService::quiescePowerTree(
+       void * target, IOPMCompletionAction action, void * param )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
+       }
+       if (!target || !action) {
+               return kIOReturnBadArgument;
+       }
+
+       OUR_PMLog(kPMLogQuiescePowerTree, 0, 0);
+
+       // Target the root node instead of root domain. This is to avoid blocking
+       // the quiesce request behind an existing root domain request in the work
+       // queue. Root parent and root domain requests in the work queue must not
+       // block the completion of the quiesce request.
+
+       request = acquirePMRequest(gIOPMRootNode, kIOPMRequestTypeQuiescePowerTree);
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       request->installCompletionAction(target, action, param);
+
+       // Submit through the normal request flow. This will make sure any request
+       // already in the request queue will get pushed over to the work queue for
+       // execution. Any request submitted after this request may not be serviced.
+
+       submitPMRequest( request );
+       return kIOReturnSuccess;
+}
+
+//*********************************************************************************
+// [private] requestPowerState
+//*********************************************************************************
+
+IOReturn
+IOService::requestPowerState(
+       const OSSymbol *      client,
+       uint32_t              state )
+{
+       IOPMRequest * request;
+
+       if (!client) {
+               return kIOReturnBadArgument;
+       }
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
+       }
+
+       request = acquirePMRequest( this, kIOPMRequestTypeRequestPowerState );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       client->retain();
+       request->fArg0 = (void *)(uintptr_t) state;
+       request->fArg1 = (void *)            client;
+       request->fArg2 = NULL;
+#if NOT_READY
+       if (action) {
+               request->installCompletionAction( action, target, param );
+       }
+#endif
+
+       // Prevent needless downwards power transitions by clamping power
+       // until the scheduled request is executed.
+
+       if (gIOPMWorkLoop->inGate() && (state < fNumberOfPowerStates)) {
+               fTempClampPowerState = StateMax(fTempClampPowerState, state);
+               fTempClampCount++;
+               request->fArg2 = (void *) (uintptr_t) true;
+       }
+
+       submitPMRequest( request );
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [private] handleRequestPowerState
+//*********************************************************************************
+
+void
+IOService::handleRequestPowerState( IOPMRequest * request )
+{
+       const OSSymbol * client = (const OSSymbol *)    request->fArg1;
+       uint32_t         state  = (uint32_t)(uintptr_t) request->fArg0;
+
+       PM_ASSERT_IN_GATE();
+       if (request->fArg2) {
+               assert(fTempClampCount != 0);
+               if (fTempClampCount) {
+                       fTempClampCount--;
+               }
+               if (!fTempClampCount) {
+                       fTempClampPowerState = kPowerStateZero;
+               }
+       }
+
+       if (fNumberOfPowerStates && (state >= fNumberOfPowerStates)) {
+               state = fHighestPowerState;
+       }
+
+       // The power suppression due to changePowerStateWithOverrideTo() expires
+       // upon the next "device" power request - changePowerStateToPriv().
+
+       if ((getPMRequestType() != kIOPMRequestTypeRequestPowerStateOverride) &&
+           (client == gIOPMPowerClientDevice)) {
+               fOverrideMaxPowerState = kIOPMPowerStateMax;
+       }
+
+       if ((state == kPowerStateZero) &&
+           (client != gIOPMPowerClientDevice) &&
+           (client != gIOPMPowerClientDriver) &&
+           (client != gIOPMPowerClientChildProxy)) {
+               removePowerClient(client);
+       } else {
+               updatePowerClient(client, state);
+       }
+
+       adjustPowerState();
+       client->release();
+}
+
+//*********************************************************************************
+// [private] Helper functions to update/remove power clients.
+//*********************************************************************************
+
+void
+IOService::updatePowerClient( const OSSymbol * client, uint32_t powerState )
+{
+       IOPMPowerStateIndex oldPowerState = kPowerStateZero;
+
+       if (!fPowerClients) {
+               fPowerClients = OSDictionary::withCapacity(4);
+       }
+       if (fPowerClients && client) {
+               OSNumber * num = (OSNumber *) fPowerClients->getObject(client);
+               if (num) {
+                       oldPowerState = num->unsigned32BitValue();
+                       num->setValue(powerState);
+               } else {
+                       num = OSNumber::withNumber(powerState, 32);
+                       if (num) {
+                               fPowerClients->setObject(client, num);
+                               num->release();
+                       }
+               }
+
+               PM_ACTION_3(actionUpdatePowerClient, client, oldPowerState, powerState);
+       }
+}
+
+void
+IOService::removePowerClient( const OSSymbol * client )
+{
+       if (fPowerClients && client) {
+               fPowerClients->removeObject(client);
+       }
+}
+
+uint32_t
+IOService::getPowerStateForClient( const OSSymbol * client )
+{
+       uint32_t powerState = kPowerStateZero;
+
+       if (fPowerClients && client) {
+               OSNumber * num = (OSNumber *) fPowerClients->getObject(client);
+               if (num) {
+                       powerState = num->unsigned32BitValue();
+               }
+       }
+       return powerState;
+}
+
+//*********************************************************************************
+// [protected] powerOverrideOnPriv
+//*********************************************************************************
+
+IOReturn
+IOService::powerOverrideOnPriv( void )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       if (gIOPMWorkLoop->inGate()) {
+               fDeviceOverrideEnabled = true;
+               return IOPMNoErr;
+       }
+
+       request = acquirePMRequest( this, kIOPMRequestTypePowerOverrideOnPriv );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       submitPMRequest( request );
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [protected] powerOverrideOffPriv
+//*********************************************************************************
+
+IOReturn
+IOService::powerOverrideOffPriv( void )
+{
+       IOPMRequest * request;
+
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       if (gIOPMWorkLoop->inGate()) {
+               fDeviceOverrideEnabled = false;
+               return IOPMNoErr;
+       }
+
+       request = acquirePMRequest( this, kIOPMRequestTypePowerOverrideOffPriv );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       submitPMRequest( request );
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [private] handlePowerOverrideChanged
+//*********************************************************************************
+
+void
+IOService::handlePowerOverrideChanged( IOPMRequest * request )
+{
+       PM_ASSERT_IN_GATE();
+       if (request->getType() == kIOPMRequestTypePowerOverrideOnPriv) {
+               OUR_PMLog(kPMLogOverrideOn, 0, 0);
+               fDeviceOverrideEnabled = true;
+       } else {
+               OUR_PMLog(kPMLogOverrideOff, 0, 0);
+               fDeviceOverrideEnabled = false;
+       }
+
+       adjustPowerState();
+}
+
+//*********************************************************************************
+// [private] computeDesiredState
+//*********************************************************************************
+
+void
+IOService::computeDesiredState( unsigned long localClamp, bool computeOnly )
+{
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * connection;
+       uint32_t            desiredState  = kPowerStateZero;
+       uint32_t            newPowerState = kPowerStateZero;
+       bool                hasChildren   = false;
+
+       // Desired power state is always 0 without a controlling driver.
+
+       if (!fNumberOfPowerStates) {
+               fDesiredPowerState = kPowerStateZero;
+               return;
+       }
+
+       // Examine the children's desired power state.
+
+       iter = getChildIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((connection = OSDynamicCast(IOPowerConnection, next))) {
+                               if (connection->getReadyFlag() == false) {
+                                       PM_LOG3("[%s] %s: connection not ready\n",
+                                           getName(), __FUNCTION__);
+                                       continue;
+                               }
+                               if (connection->childHasRequestedPower()) {
+                                       hasChildren = true;
+                               }
+                               desiredState = StateMax(connection->getDesiredDomainState(), desiredState);
+                       }
+               }
+               iter->release();
+       }
+       if (hasChildren) {
+               updatePowerClient(gIOPMPowerClientChildren, desiredState);
+       } else {
+               removePowerClient(gIOPMPowerClientChildren);
+       }
+
+       // Iterate through all power clients to determine the min power state.
+
+       iter = OSCollectionIterator::withCollection(fPowerClients);
+       if (iter) {
+               const OSSymbol * client;
+               while ((client = (const OSSymbol *) iter->getNextObject())) {
+                       // Ignore child and driver when override is in effect.
+                       if ((fDeviceOverrideEnabled ||
+                           (getPMRequestType() == kIOPMRequestTypeRequestPowerStateOverride)) &&
+                           ((client == gIOPMPowerClientChildren) ||
+                           (client == gIOPMPowerClientDriver))) {
+                               continue;
+                       }
+
+                       // Ignore child proxy when children are present.
+                       if (hasChildren && (client == gIOPMPowerClientChildProxy)) {
+                               continue;
+                       }
+
+                       // Advisory tickles are irrelevant unless system is in full wake
+                       if (client == gIOPMPowerClientAdvisoryTickle &&
+                           !gIOPMAdvisoryTickleEnabled) {
+                               continue;
+                       }
+
+                       desiredState = getPowerStateForClient(client);
+                       assert(desiredState < fNumberOfPowerStates);
+                       PM_LOG1("  %u %s\n",
+                           desiredState, client->getCStringNoCopy());
+
+                       newPowerState = StateMax(newPowerState, desiredState);
+
+                       if (client == gIOPMPowerClientDevice) {
+                               fDeviceDesire = desiredState;
+                       }
+               }
+               iter->release();
+       }
+
+       // Factor in the temporary power desires.
+
+       newPowerState = StateMax(newPowerState, localClamp);
+       newPowerState = StateMax(newPowerState, fTempClampPowerState);
+
+       // Limit check against max power override.
+
+       newPowerState = StateMin(newPowerState, fOverrideMaxPowerState);
+
+       // Limit check against number of power states.
+
+       if (newPowerState >= fNumberOfPowerStates) {
+               newPowerState = fHighestPowerState;
+       }
+
+#if !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146))
+       if (getPMRootDomain()->isAOTMode()) {
+               if ((kIOPMPreventIdleSleep & fPowerStates[newPowerState].capabilityFlags)
+                   && !(kIOPMPreventIdleSleep & fPowerStates[fDesiredPowerState].capabilityFlags)) {
+                       getPMRootDomain()->claimSystemWakeEvent(this, kIOPMWakeEventAOTExit, getName(), NULL);
+               }
+       }
+#endif /* !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+
+       fDesiredPowerState = newPowerState;
+
+       PM_LOG1("  temp %u, clamp %u, current %u, new %u\n",
+           (uint32_t) localClamp, (uint32_t) fTempClampPowerState,
+           (uint32_t) fCurrentPowerState, newPowerState);
+
+       if (!computeOnly) {
+               // Restart idle timer if possible when device desire has increased.
+               // Or if an advisory desire exists.
+
+               if (fIdleTimerPeriod && fIdleTimerStopped) {
+                       restartIdleTimer();
+               }
+
+               // Invalidate cached tickle power state when desires change, and not
+               // due to a tickle request. In case the driver has requested a lower
+               // power state, but the tickle is caching a higher power state which
+               // will drop future tickles until the cached value is lowered or in-
+               // validated. The invalidation must occur before the power transition
+               // to avoid dropping a necessary tickle.
+
+               if ((getPMRequestType() != kIOPMRequestTypeActivityTickle) &&
+                   (fActivityTicklePowerState != kInvalidTicklePowerState)) {
+                       IOLockLock(fActivityLock);
+                       fActivityTicklePowerState = kInvalidTicklePowerState;
+                       IOLockUnlock(fActivityLock);
+               }
+       }
+}
+
+//*********************************************************************************
+// [public] currentPowerConsumption
+//
+//*********************************************************************************
+
+unsigned long
+IOService::currentPowerConsumption( void )
+{
+       if (!initialized) {
+               return kIOPMUnknown;
+       }
+
+       return fCurrentPowerConsumption;
+}
+
+//*********************************************************************************
+// [deprecated] getPMworkloop
+//*********************************************************************************
+
+#ifndef __LP64__
+IOWorkLoop *
+IOService::getPMworkloop( void )
+{
+       return gIOPMWorkLoop;
+}
+#endif
+
+#if NOT_YET
+
+//*********************************************************************************
+// Power Parent/Children Applier
+//*********************************************************************************
+
+static void
+applyToPowerChildren(
+       IOService *               service,
+       IOServiceApplierFunction  applier,
+       void *                    context,
+       IOOptionBits              options )
+{
+       PM_ASSERT_IN_GATE();
+
+       IORegistryEntry *       entry;
+       IORegistryIterator *    iter;
+       IOPowerConnection *     connection;
+       IOService *             child;
+
+       iter = IORegistryIterator::iterateOver(service, gIOPowerPlane, options);
+       if (iter) {
+               while ((entry = iter->getNextObject())) {
+                       // Get child of IOPowerConnection objects
+                       if ((connection = OSDynamicCast(IOPowerConnection, entry))) {
+                               child = (IOService *) connection->copyChildEntry(gIOPowerPlane);
+                               if (child) {
+                                       (*applier)(child, context);
+                                       child->release();
+                               }
+                       }
+               }
+               iter->release();
+       }
+}
+
+static void
+applyToPowerParent(
+       IOService *               service,
+       IOServiceApplierFunction  applier,
+       void *                    context,
+       IOOptionBits              options )
+{
+       PM_ASSERT_IN_GATE();
+
+       IORegistryEntry *       entry;
+       IORegistryIterator *    iter;
+       IOPowerConnection *     connection;
+       IOService *             parent;
+
+       iter = IORegistryIterator::iterateOver(service, gIOPowerPlane,
+           options | kIORegistryIterateParents);
+       if (iter) {
+               while ((entry = iter->getNextObject())) {
+                       // Get child of IOPowerConnection objects
+                       if ((connection = OSDynamicCast(IOPowerConnection, entry))) {
+                               parent = (IOService *) connection->copyParentEntry(gIOPowerPlane);
+                               if (parent) {
+                                       (*applier)(parent, context);
+                                       parent->release();
+                               }
+                       }
+               }
+               iter->release();
+       }
+}
+
+#endif /* NOT_YET */
+
+// MARK: -
+// MARK: Activity Tickle & Idle Timer
+
+void
+IOService::setAdvisoryTickleEnable( bool enable )
+{
+       gIOPMAdvisoryTickleEnabled = enable;
+}
+
+//*********************************************************************************
+// [public] activityTickle
+//
+// The tickle with parameter kIOPMSuperclassPolicy1 causes the activity
+// flag to be set, and the device state checked.  If the device has been
+// powered down, it is powered up again.
+// The tickle with parameter kIOPMSubclassPolicy is ignored here and
+// should be intercepted by a subclass.
+//*********************************************************************************
+
+bool
+IOService::activityTickle( unsigned long type, unsigned long stateNumber )
+{
+       IOPMRequest *   request;
+       bool            noPowerChange = true;
+       uint32_t        tickleFlags;
+
+       if (!initialized) {
+               return true; // no power change
+       }
+       if ((type == kIOPMSuperclassPolicy1) && StateOrder(stateNumber)) {
+               IOLockLock(fActivityLock);
+
+               // Record device activity for the idle timer handler.
+
+               fDeviceWasActive = true;
+               fActivityTickleCount++;
+               clock_get_uptime(&fDeviceActiveTimestamp);
+
+               PM_ACTION_0(actionActivityTickle);
+
+               // Record the last tickle power state.
+               // This helps to filter out redundant tickles as
+               // this function may be called from the data path.
+
+               if ((fActivityTicklePowerState == kInvalidTicklePowerState)
+                   || StateOrder(fActivityTicklePowerState) < StateOrder(stateNumber)) {
+                       fActivityTicklePowerState = stateNumber;
+                       noPowerChange = false;
+
+                       tickleFlags = kTickleTypeActivity | kTickleTypePowerRise;
+                       request = acquirePMRequest( this, kIOPMRequestTypeActivityTickle );
+                       if (request) {
+                               request->fArg0 = (void *)            stateNumber;
+                               request->fArg1 = (void *)(uintptr_t) tickleFlags;
+                               request->fArg2 = (void *)(uintptr_t) gIOPMTickleGeneration;
+                               submitPMRequest(request);
+                       }
+               }
+
+               IOLockUnlock(fActivityLock);
+       } else if ((type == kIOPMActivityTickleTypeAdvisory) &&
+           ((stateNumber = fDeviceUsablePowerState) != kPowerStateZero)) {
+               IOLockLock(fActivityLock);
+
+               fAdvisoryTickled = true;
+
+               if (fAdvisoryTicklePowerState != stateNumber) {
+                       fAdvisoryTicklePowerState = stateNumber;
+                       noPowerChange = false;
+
+                       tickleFlags = kTickleTypeAdvisory | kTickleTypePowerRise;
+                       request = acquirePMRequest( this, kIOPMRequestTypeActivityTickle );
+                       if (request) {
+                               request->fArg0 = (void *)            stateNumber;
+                               request->fArg1 = (void *)(uintptr_t) tickleFlags;
+                               request->fArg2 = (void *)(uintptr_t) gIOPMTickleGeneration;
+                               submitPMRequest(request);
+                       }
+               }
+
+               IOLockUnlock(fActivityLock);
+       }
+
+       // Returns false if the activityTickle might cause a transition to a
+       // higher powered state, true otherwise.
+
+       return noPowerChange;
+}
+
+//*********************************************************************************
+// [private] handleActivityTickle
+//*********************************************************************************
+
+void
+IOService::handleActivityTickle( IOPMRequest * request )
+{
+       uint32_t ticklePowerState   = (uint32_t)(uintptr_t) request->fArg0;
+       uint32_t tickleFlags        = (uint32_t)(uintptr_t) request->fArg1;
+       uint32_t tickleGeneration   = (uint32_t)(uintptr_t) request->fArg2;
+       bool     adjustPower        = false;
+
+       PM_ASSERT_IN_GATE();
+       if (fResetPowerStateOnWake && (tickleGeneration != gIOPMTickleGeneration)) {
+               // Drivers that don't want power restored on wake will drop any
+               // tickles that pre-dates the current system wake. The model is
+               // that each wake is a fresh start, with power state depressed
+               // until a new tickle or an explicit power up request from the
+               // driver. It is possible for the PM work loop to enter the
+               // system sleep path with tickle requests queued.
+
+               return;
+       }
+
+       if (tickleFlags & kTickleTypeActivity) {
+               IOPMPowerStateIndex deviceDesireOrder = StateOrder(fDeviceDesire);
+               uint32_t idleTimerGeneration = ticklePowerState; // kTickleTypePowerDrop
+
+               if (tickleFlags & kTickleTypePowerRise) {
+                       if ((StateOrder(ticklePowerState) > deviceDesireOrder) &&
+                           (ticklePowerState < fNumberOfPowerStates)) {
+                               fIdleTimerMinPowerState = ticklePowerState;
+                               updatePowerClient(gIOPMPowerClientDevice, ticklePowerState);
+                               adjustPower = true;
+                       }
+               } else if ((deviceDesireOrder > StateOrder(fIdleTimerMinPowerState)) &&
+                   (idleTimerGeneration == fIdleTimerGeneration)) {
+                       // Power drop due to idle timer expiration.
+                       // Do not allow idle timer to reduce power below tickle power.
+                       // This prevents the idle timer from decreasing the device desire
+                       // to zero and cancelling the effect of a pre-sleep tickle when
+                       // system wakes up to doze state, while the device is unable to
+                       // raise its power state to satisfy the tickle.
+
+                       deviceDesireOrder--;
+                       if (deviceDesireOrder < fNumberOfPowerStates) {
+                               ticklePowerState = fPowerStates[deviceDesireOrder].stateOrderToIndex;
+                               updatePowerClient(gIOPMPowerClientDevice, ticklePowerState);
+                               adjustPower = true;
+                       }
+               }
+       } else { // advisory tickle
+               if (tickleFlags & kTickleTypePowerRise) {
+                       if ((ticklePowerState == fDeviceUsablePowerState) &&
+                           (ticklePowerState < fNumberOfPowerStates)) {
+                               updatePowerClient(gIOPMPowerClientAdvisoryTickle, ticklePowerState);
+                               fHasAdvisoryDesire = true;
+                               fAdvisoryTickleUsed = true;
+                               adjustPower = true;
+                       } else {
+                               IOLockLock(fActivityLock);
+                               fAdvisoryTicklePowerState = kInvalidTicklePowerState;
+                               IOLockUnlock(fActivityLock);
+                       }
+               } else if (fHasAdvisoryDesire) {
+                       removePowerClient(gIOPMPowerClientAdvisoryTickle);
+                       fHasAdvisoryDesire = false;
+                       adjustPower = true;
+               }
+       }
+
+       if (adjustPower) {
+               adjustPowerState();
+       }
+}
+
+//******************************************************************************
+// [public] setIdleTimerPeriod
+//
+// A subclass policy-maker is using our standard idleness detection service.
+// Start the idle timer. Period is in seconds.
+//******************************************************************************
+
+IOReturn
+IOService::setIdleTimerPeriod( unsigned long period )
+{
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       OUR_PMLog(kPMLogSetIdleTimerPeriod, period, fIdleTimerPeriod);
+
+       IOPMRequest * request =
+           acquirePMRequest( this, kIOPMRequestTypeSetIdleTimerPeriod );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       request->fArg0 = (void *) period;
+       submitPMRequest( request );
+
+       return kIOReturnSuccess;
+}
+
+IOReturn
+IOService::setIgnoreIdleTimer( bool ignore )
+{
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
+
+       OUR_PMLog(kIOPMRequestTypeIgnoreIdleTimer, ignore, 0);
+
+       IOPMRequest * request =
+           acquirePMRequest( this, kIOPMRequestTypeIgnoreIdleTimer );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       request->fArg0 = (void *) ignore;
+       submitPMRequest( request );
+
+       return kIOReturnSuccess;
+}
+
+//******************************************************************************
+// [public] nextIdleTimeout
+//
+// Returns how many "seconds from now" the device should idle into its
+// next lowest power state.
+//******************************************************************************
+
+SInt32
+IOService::nextIdleTimeout(
+       AbsoluteTime currentTime,
+       AbsoluteTime lastActivity,
+       unsigned int powerState)
+{
+       AbsoluteTime        delta;
+       UInt64              delta_ns;
+       SInt32              delta_secs;
+       SInt32              delay_secs;
+
+       // Calculate time difference using funky macro from clock.h.
+       delta = currentTime;
+       SUB_ABSOLUTETIME(&delta, &lastActivity);
+
+       // Figure it in seconds.
+       absolutetime_to_nanoseconds(delta, &delta_ns);
+       delta_secs = (SInt32)(delta_ns / NSEC_PER_SEC);
+
+       // Be paranoid about delta somehow exceeding timer period.
+       if (delta_secs < (int) fIdleTimerPeriod) {
+               delay_secs = (int) fIdleTimerPeriod - delta_secs;
+       } else {
+               delay_secs = (int) fIdleTimerPeriod;
+       }
+
+       return (SInt32)delay_secs;
+}
+
+//*********************************************************************************
+// [public] start_PM_idle_timer
+//*********************************************************************************
+
+void
+IOService::start_PM_idle_timer( void )
+{
+       static const int    maxTimeout = 100000;
+       static const int    minTimeout = 1;
+       AbsoluteTime        uptime, deadline;
+       SInt32              idle_in = 0;
+       boolean_t           pending;
+
+       if (!initialized || !fIdleTimerPeriod) {
+               return;
+       }
+
+       IOLockLock(fActivityLock);
+
+       clock_get_uptime(&uptime);
+
+       // Subclasses may modify idle sleep algorithm
+       idle_in = nextIdleTimeout(uptime, fDeviceActiveTimestamp, fCurrentPowerState);
+
+       // Check for out-of range responses
+       if (idle_in > maxTimeout) {
+               // use standard implementation
+               idle_in = IOService::nextIdleTimeout(uptime,
+                   fDeviceActiveTimestamp,
+                   fCurrentPowerState);
+       } else if (idle_in < minTimeout) {
+               idle_in = fIdleTimerPeriod;
+       }
+
+       IOLockUnlock(fActivityLock);
+
+       fNextIdleTimerPeriod = idle_in;
+       fIdleTimerStartTime = uptime;
+
+       retain();
+       clock_interval_to_absolutetime_interval(idle_in, kSecondScale, &deadline);
+       ADD_ABSOLUTETIME(&deadline, &uptime);
+       pending = thread_call_enter_delayed(fIdleTimer, deadline);
+       if (pending) {
+               release();
+       }
+}
+
+//*********************************************************************************
+// [private] restartIdleTimer
+//*********************************************************************************
+
+void
+IOService::restartIdleTimer( void )
+{
+       if (fDeviceDesire != kPowerStateZero) {
+               fIdleTimerStopped = false;
+               fActivityTickleCount = 0;
+               start_PM_idle_timer();
+       } else if (fHasAdvisoryDesire) {
+               fIdleTimerStopped = false;
+               start_PM_idle_timer();
+       } else {
+               fIdleTimerStopped = true;
+       }
+}
+
+//*********************************************************************************
+// idle_timer_expired
+//*********************************************************************************
+
+static void
+idle_timer_expired(
+       thread_call_param_t arg0, thread_call_param_t arg1 )
+{
+       IOService * me = (IOService *) arg0;
+
+       if (gIOPMWorkLoop) {
+               gIOPMWorkLoop->runAction(
+                       OSMemberFunctionCast(IOWorkLoop::Action, me,
+                       &IOService::idleTimerExpired),
+                       me);
+       }
+
+       me->release();
+}
+
+//*********************************************************************************
+// [private] idleTimerExpired
+//
+// The idle timer has expired. If there has been activity since the last
+// expiration, just restart the timer and return.  If there has not been
+// activity, switch to the next lower power state and restart the timer.
+//*********************************************************************************
+
+void
+IOService::idleTimerExpired( void )
+{
+       IOPMRequest *   request;
+       bool            restartTimer = true;
+       uint32_t        tickleFlags;
+
+       if (!initialized || !fIdleTimerPeriod || fIdleTimerStopped ||
+           fLockedFlags.PMStop) {
+               return;
+       }
+
+       fIdleTimerStartTime = 0;
+
+       IOLockLock(fActivityLock);
+
+       // Check for device activity (tickles) over last timer period.
+
+       if (fDeviceWasActive) {
+               // Device was active - do not drop power, restart timer.
+               fDeviceWasActive = false;
+       } else if (!fIdleTimerIgnored) {
+               // No device activity - drop power state by one level.
+               // Decrement the cached tickle power state when possible.
+               // This value may be kInvalidTicklePowerState before activityTickle()
+               // is called, but the power drop request must be issued regardless.
+
+               if ((fActivityTicklePowerState != kInvalidTicklePowerState) &&
+                   (fActivityTicklePowerState != kPowerStateZero)) {
+                       fActivityTicklePowerState--;
+               }
+
+               tickleFlags = kTickleTypeActivity | kTickleTypePowerDrop;
+               request = acquirePMRequest( this, kIOPMRequestTypeActivityTickle );
+               if (request) {
+                       request->fArg0 = (void *)(uintptr_t) fIdleTimerGeneration;
+                       request->fArg1 = (void *)(uintptr_t) tickleFlags;
+                       request->fArg2 = (void *)(uintptr_t) gIOPMTickleGeneration;
+                       submitPMRequest( request );
+
+                       // Do not restart timer until after the tickle request has been
+                       // processed.
+
+                       restartTimer = false;
+               }
+       }
+
+       if (fAdvisoryTickled) {
+               fAdvisoryTickled = false;
+       } else if (fHasAdvisoryDesire) {
+               // Want new tickles to turn into pm request after we drop the lock
+               fAdvisoryTicklePowerState = kInvalidTicklePowerState;
+
+               tickleFlags = kTickleTypeAdvisory | kTickleTypePowerDrop;
+               request = acquirePMRequest( this, kIOPMRequestTypeActivityTickle );
+               if (request) {
+                       request->fArg0 = (void *)(uintptr_t) fIdleTimerGeneration;
+                       request->fArg1 = (void *)(uintptr_t) tickleFlags;
+                       request->fArg2 = (void *)(uintptr_t) gIOPMTickleGeneration;
+                       submitPMRequest( request );
+
+                       // Do not restart timer until after the tickle request has been
+                       // processed.
+
+                       restartTimer = false;
+               }
+       }
+
+       IOLockUnlock(fActivityLock);
+
+       if (restartTimer) {
+               start_PM_idle_timer();
+       }
+}
+
+#ifndef __LP64__
+//*********************************************************************************
+// [deprecated] PM_idle_timer_expiration
+//*********************************************************************************
+
+void
+IOService::PM_idle_timer_expiration( void )
+{
+}
+
+//*********************************************************************************
+// [deprecated] command_received
+//*********************************************************************************
+
+void
+IOService::command_received( void *statePtr, void *, void *, void * )
+{
+}
+#endif /* !__LP64__ */
+
+//*********************************************************************************
+// [public] setAggressiveness
+//
+// Pass on the input parameters to all power domain children. All those which are
+// power domains will pass it on to their children, etc.
+//*********************************************************************************
+
+IOReturn
+IOService::setAggressiveness( unsigned long type, unsigned long newLevel )
+{
+       return kIOReturnSuccess;
+}
+
+//*********************************************************************************
+// [public] getAggressiveness
+//
+// Called by the user client.
+//*********************************************************************************
+
+IOReturn
+IOService::getAggressiveness( unsigned long type, unsigned long * currentLevel )
+{
+       IOPMrootDomain *    rootDomain = getPMRootDomain();
+
+       if (!rootDomain) {
+               return kIOReturnNotReady;
+       }
+
+       return rootDomain->getAggressiveness( type, currentLevel );
+}
+
+//*********************************************************************************
+// [public] getPowerState
+//
+//*********************************************************************************
+
+UInt32
+IOService::getPowerState( void )
+{
+       if (!initialized) {
+               return kPowerStateZero;
+       }
+
+       return fCurrentPowerState;
+}
+
+#ifndef __LP64__
+//*********************************************************************************
+// [deprecated] systemWake
+//
+// Pass this to all power domain children. All those which are
+// power domains will pass it on to their children, etc.
+//*********************************************************************************
+
+IOReturn
+IOService::systemWake( void )
+{
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * connection;
+       IOService *         theChild;
+
+       iter = getChildIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((connection = OSDynamicCast(IOPowerConnection, next))) {
+                               if (connection->getReadyFlag() == false) {
+                                       PM_LOG3("[%s] %s: connection not ready\n",
+                                           getName(), __FUNCTION__);
+                                       continue;
+                               }
+
+                               theChild = (IOService *)connection->copyChildEntry(gIOPowerPlane);
+                               if (theChild) {
+                                       theChild->systemWake();
+                                       theChild->release();
+                               }
+                       }
+               }
+               iter->release();
+       }
+
+       if (fControllingDriver != NULL) {
+               if (fControllingDriver->didYouWakeSystem()) {
+                       makeUsable();
+               }
+       }
+
+       return IOPMNoErr;
+}
+
+//*********************************************************************************
+// [deprecated] temperatureCriticalForZone
+//*********************************************************************************
+
+IOReturn
+IOService::temperatureCriticalForZone( IOService * whichZone )
+{
+       IOService * theParent;
+       IOService * theNub;
+
+       OUR_PMLog(kPMLogCriticalTemp, 0, 0);
+
+       if (inPlane(gIOPowerPlane) && !IS_PM_ROOT) {
+               theNub = (IOService *)copyParentEntry(gIOPowerPlane);
+               if (theNub) {
+                       theParent = (IOService *)theNub->copyParentEntry(gIOPowerPlane);
+                       theNub->release();
+                       if (theParent) {
+                               theParent->temperatureCriticalForZone(whichZone);
+                               theParent->release();
+                       }
+               }
+       }
+       return IOPMNoErr;
+}
+#endif /* !__LP64__ */
+
+// MARK: -
+// MARK: Power Change (Common)
+
+//*********************************************************************************
+// [private] startPowerChange
+//
+// All power state changes starts here.
+//*********************************************************************************
+
+IOReturn
+IOService::startPowerChange(
+       IOPMPowerChangeFlags    changeFlags,
+       IOPMPowerStateIndex     powerState,
+       IOPMPowerFlags          domainFlags,
+       IOPowerConnection *     parentConnection,
+       IOPMPowerFlags          parentFlags )
+{
+       uint32_t savedPMActionsParam;
+
+       PM_ASSERT_IN_GATE();
+       assert( fMachineState == kIOPM_Finished );
+       assert( powerState < fNumberOfPowerStates );
+
+       if (powerState >= fNumberOfPowerStates) {
+               return IOPMAckImplied;
+       }
+
+       fIsPreChange = true;
+       savedPMActionsParam = fPMActions.parameter;
+       PM_ACTION_2(actionPowerChangeOverride, &powerState, &changeFlags);
+
+       // rdar://problem/55040032
+       // Schedule a power adjustment after removing the power clamp
+       // to inform our power parent(s) about our latest desired domain
+       // power state. For a self-initiated change, let OurChangeStart()
+       // automatically request parent power when necessary.
+       if (!fAdjustPowerScheduled &&
+           ((changeFlags & kIOPMSelfInitiated) == 0) &&
+           ((fPMActions.parameter & kPMActionsFlagLimitPower) == 0) &&
+           ((savedPMActionsParam  & kPMActionsFlagLimitPower) != 0)) {
+               IOPMRequest * request = acquirePMRequest(this, kIOPMRequestTypeAdjustPowerState);
+               if (request) {
+                       submitPMRequest(request);
+                       fAdjustPowerScheduled = true;
+               }
+       }
+
+       if (changeFlags & kIOPMExpireIdleTimer) {
+               // Root domain requested removal of tickle influence
+               if (StateOrder(fDeviceDesire) > StateOrder(powerState)) {
+                       // Reset device desire down to the clamped power state
+                       updatePowerClient(gIOPMPowerClientDevice, powerState);
+                       computeDesiredState(kPowerStateZero, true);
+
+                       // Invalidate tickle cache so the next tickle will issue a request
+                       IOLockLock(fActivityLock);
+                       fDeviceWasActive = false;
+                       fActivityTicklePowerState = kInvalidTicklePowerState;
+                       IOLockUnlock(fActivityLock);
+
+                       fIdleTimerMinPowerState = kPowerStateZero;
+               }
+       }
+
+       // Root domain's override handler may cancel the power change by
+       // setting the kIOPMNotDone flag.
+
+       if (changeFlags & kIOPMNotDone) {
+               return IOPMAckImplied;
+       }
+
+       // Forks to either Driver or Parent initiated power change paths.
+
+       fHeadNoteChangeFlags      = changeFlags;
+       fHeadNotePowerState       = powerState;
+       fHeadNotePowerArrayEntry  = &fPowerStates[powerState];
+       fHeadNoteParentConnection = NULL;
+
+       if (changeFlags & kIOPMSelfInitiated) {
+               if (changeFlags & kIOPMSynchronize) {
+                       OurSyncStart();
+               } else {
+                       OurChangeStart();
+               }
+               return 0;
+       } else {
+               assert(changeFlags & kIOPMParentInitiated);
+               fHeadNoteDomainFlags = domainFlags;
+               fHeadNoteParentFlags = parentFlags;
+               fHeadNoteParentConnection = parentConnection;
+               return ParentChangeStart();
+       }
+}
+
+//*********************************************************************************
+// [private] notifyInterestedDrivers
+//*********************************************************************************
+
+bool
+IOService::notifyInterestedDrivers( void )
+{
+       IOPMinformee *      informee;
+       IOPMinformeeList *  list = fInterestedDrivers;
+       DriverCallParam *   param;
+       IOItemCount         count;
+       IOItemCount         skipCnt = 0;
+
+       PM_ASSERT_IN_GATE();
+       assert( fDriverCallParamCount == 0 );
+       assert( fHeadNotePendingAcks == 0 );
+
+       fHeadNotePendingAcks = 0;
+
+       count = list->numberOfItems();
+       if (!count) {
+               goto done; // no interested drivers
+       }
+       // Allocate an array of interested drivers and their return values
+       // for the callout thread. Everything else is still "owned" by the
+       // PM work loop, which can run to process acknowledgePowerChange()
+       // responses.
+
+       param = (DriverCallParam *) fDriverCallParamPtr;
+       if (count > fDriverCallParamSlots) {
+               if (fDriverCallParamSlots) {
+                       assert(fDriverCallParamPtr);
+                       IODelete(fDriverCallParamPtr, DriverCallParam, fDriverCallParamSlots);
+                       fDriverCallParamPtr = NULL;
+                       fDriverCallParamSlots = 0;
+               }
+
+               param = IONew(DriverCallParam, count);
+               if (!param) {
+                       goto done; // no memory
+               }
+               fDriverCallParamPtr   = (void *) param;
+               fDriverCallParamSlots = count;
+       }
+
+       informee = list->firstInList();
+       assert(informee);
+       for (IOItemCount i = 0; i < count; i++) {
+               if (fInitialSetPowerState || (fHeadNoteChangeFlags & kIOPMInitialPowerChange)) {
+                       // Skip notifying self, if 'kIOPMInitialDeviceState' is set and
+                       // this is the initial power state change
+                       if ((this == informee->whatObject) &&
+                           (fHeadNotePowerArrayEntry->capabilityFlags & kIOPMInitialDeviceState)) {
+                               skipCnt++;
+                               continue;
+                       }
+               }
+               informee->timer = -1;
+               param[i].Target = informee;
+               informee->retain();
+               informee = list->nextInList( informee );
+       }
+
+       count -= skipCnt;
+       if (!count) {
+               goto done;
+       }
+       fDriverCallParamCount = count;
+       fHeadNotePendingAcks  = count;
+
+       // Block state machine and wait for callout completion.
+       assert(!fDriverCallBusy);
+       fDriverCallBusy = true;
+       thread_call_enter( fDriverCallEntry );
+       return true;
+
+done:
+       // Return false if there are no interested drivers or could not schedule
+       // callout thread due to error.
+       return false;
+}
+
+//*********************************************************************************
+// [private] notifyInterestedDriversDone
+//*********************************************************************************
+
+void
+IOService::notifyInterestedDriversDone( void )
+{
+       IOPMinformee *      informee;
+       IOItemCount         count;
+       DriverCallParam *   param;
+       IOReturn            result;
+       int                 maxTimeout = 0;
+
+       PM_ASSERT_IN_GATE();
+       assert( fDriverCallBusy == false );
+       assert( fMachineState == kIOPM_DriverThreadCallDone );
+
+       param = (DriverCallParam *) fDriverCallParamPtr;
+       count = fDriverCallParamCount;
+
+       if (param && count) {
+               for (IOItemCount i = 0; i < count; i++, param++) {
+                       informee = (IOPMinformee *) param->Target;
+                       result   = param->Result;
+
+                       if ((result == IOPMAckImplied) || (result < 0)) {
+                               // Interested driver return IOPMAckImplied.
+                               // If informee timer is zero, it must have de-registered
+                               // interest during the thread callout. That also drops
+                               // the pending ack count.
+
+                               if (fHeadNotePendingAcks && informee->timer) {
+                                       fHeadNotePendingAcks--;
+                               }
+
+                               informee->timer = 0;
+                       } else if (informee->timer) {
+                               assert(informee->timer == -1);
+
+                               // Driver has not acked, and has returned a positive result.
+                               // Enforce a minimum permissible timeout value.
+                               // Make the min value large enough so timeout is less likely
+                               // to occur if a driver misinterpreted that the return value
+                               // should be in microsecond units.  And make it large enough
+                               // to be noticeable if a driver neglects to ack.
+
+                               if (result < kMinAckTimeoutTicks) {
+                                       result = kMinAckTimeoutTicks;
+                               }
+
+                               informee->timer = (result / (ACK_TIMER_PERIOD / ns_per_us)) + 1;
+                               if (result > maxTimeout) {
+                                       maxTimeout = result;
+                               }
+                       }
+                       // else, child has already acked or driver has removed interest,
+                       // and head_note_pendingAcks decremented.
+                       // informee may have been removed from the interested drivers list,
+                       // thus the informee must be retained across the callout.
+
+                       informee->release();
+               }
+
+               fDriverCallParamCount = 0;
+
+               if (fHeadNotePendingAcks) {
+                       OUR_PMLog(kPMLogStartAckTimer, 0, 0);
+                       start_ack_timer();
+                       getPMRootDomain()->reset_watchdog_timer(this, maxTimeout / USEC_PER_SEC + 1);
+               }
+       }
+
+       MS_POP(); // pop the machine state passed to notifyAll()
+
+       // If interest acks are outstanding, block the state machine until
+       // fHeadNotePendingAcks drops to zero before notifying root domain.
+       // Otherwise notify root domain directly.
+
+       if (!fHeadNotePendingAcks) {
+               notifyRootDomain();
+       } else {
+               MS_PUSH(fMachineState);
+               fMachineState = kIOPM_NotifyChildrenStart;
+       }
+}
+
+//*********************************************************************************
+// [private] notifyRootDomain
+//*********************************************************************************
+
+void
+IOService::notifyRootDomain( void )
+{
+       assert( fDriverCallBusy == false );
+
+       // Only for root domain in the will-change phase
+       if (!IS_ROOT_DOMAIN || (fMachineState != kIOPM_OurChangeSetPowerState)) {
+               notifyChildren();
+               return;
+       }
+
+       MS_PUSH(fMachineState); // push notifyAll() machine state
+       fMachineState = kIOPM_DriverThreadCallDone;
+
+       // Call IOPMrootDomain::willNotifyPowerChildren() on a thread call
+       // to avoid a deadlock.
+       fDriverCallReason = kRootDomainInformPreChange;
+       fDriverCallBusy   = true;
+       thread_call_enter( fDriverCallEntry );
+}
+
+void
+IOService::notifyRootDomainDone( void )
+{
+       assert( fDriverCallBusy == false );
+       assert( fMachineState == kIOPM_DriverThreadCallDone );
+
+       MS_POP(); // pop notifyAll() machine state
+       notifyChildren();
+}
+
+//*********************************************************************************
+// [private] notifyChildren
+//*********************************************************************************
+
+void
+IOService::notifyChildren( void )
+{
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * connection;
+       OSArray *           children = NULL;
+       IOPMrootDomain *    rootDomain;
+       bool                delayNotify = false;
+
+       if ((fHeadNotePowerState != fCurrentPowerState) &&
+           (IS_POWER_DROP == fIsPreChange) &&
+           ((rootDomain = getPMRootDomain()) == this)) {
+               rootDomain->tracePoint( IS_POWER_DROP ?
+                   kIOPMTracePointSleepPowerPlaneDrivers :
+                   kIOPMTracePointWakePowerPlaneDrivers  );
+       }
+
+       if (fStrictTreeOrder) {
+               children = OSArray::withCapacity(8);
+       }
+
+       // Sum child power consumption in notifyChild()
+       fHeadNotePowerArrayEntry->staticPower = 0;
+
+       iter = getChildIterator(gIOPowerPlane);
+       if (iter) {
+               while ((next = iter->getNextObject())) {
+                       if ((connection = OSDynamicCast(IOPowerConnection, next))) {
+                               if (connection->getReadyFlag() == false) {
+                                       PM_LOG3("[%s] %s: connection not ready\n",
+                                           getName(), __FUNCTION__);
+                                       continue;
+                               }
+
+                               // Mechanism to postpone the did-change notification to
+                               // certain power children to order those children last.
+                               // Cannot be used together with strict tree ordering.
+
+                               if (!fIsPreChange &&
+                                   connection->delayChildNotification &&
+                                   getPMRootDomain()->shouldDelayChildNotification(this)) {
+                                       if (!children) {
+                                               children = OSArray::withCapacity(8);
+                                               if (children) {
+                                                       delayNotify = true;
+                                               }
+                                       }
+                                       if (delayNotify) {
+                                               children->setObject( connection );
+                                               continue;
+                                       }
+                               }
+
+                               if (!delayNotify && children) {
+                                       children->setObject( connection );
+                               } else {
+                                       notifyChild( connection );
+                               }
+                       }
+               }
+               iter->release();
+       }
+
+       if (children && (children->getCount() == 0)) {
+               children->release();
+               children = NULL;
+       }
+       if (children) {
+               assert(fNotifyChildArray == NULL);
+               fNotifyChildArray = children;
+               MS_PUSH(fMachineState);
+
+               if (delayNotify) {
+                       // Block until all non-delayed children have acked their
+                       // notification. Then notify the remaining delayed child
+                       // in the array. This is used to hold off graphics child
+                       // notification while the rest of the system powers up.
+                       // If a hid tickle arrives during this time, the delayed
+                       // children are immediately notified and root domain will
+                       // not clamp power for dark wake.
+
+                       fMachineState = kIOPM_NotifyChildrenDelayed;
+                       PM_LOG2("%s: %d children in delayed array\n",
+                           getName(), children->getCount());
+               } else {
+                       // Child array created to support strict notification order.
+                       // Notify children in the array one at a time.
+
+                       fMachineState = kIOPM_NotifyChildrenOrdered;
+               }
+       }
+}
+
+//*********************************************************************************
+// [private] notifyChildrenOrdered
+//*********************************************************************************
+
+void
+IOService::notifyChildrenOrdered( void )
+{
+       PM_ASSERT_IN_GATE();
+       assert(fNotifyChildArray);
+       assert(fMachineState == kIOPM_NotifyChildrenOrdered);
+
+       // Notify one child, wait for it to ack, then repeat for next child.
+       // This is a workaround for some drivers with multiple instances at
+       // the same branch in the power tree, but the driver is slow to power
+       // up unless the tree ordering is observed. Problem observed only on
+       // system wake, not on system sleep.
+       //
+       // We have the ability to power off in reverse child index order.
+       // That works nicely on some machines, but not on all HW configs.
+
+       if (fNotifyChildArray->getCount()) {
+               IOPowerConnection * connection;
+               connection = (IOPowerConnection *) fNotifyChildArray->getObject(0);
+               notifyChild( connection );
+               fNotifyChildArray->removeObject(0);
+       } else {
+               fNotifyChildArray->release();
+               fNotifyChildArray = NULL;
+
+               MS_POP(); // pushed by notifyChildren()
+       }
+}
+
+//*********************************************************************************
+// [private] notifyChildrenDelayed
+//*********************************************************************************
+
+void
+IOService::notifyChildrenDelayed( void )
+{
+       IOPowerConnection * connection;
+
+       PM_ASSERT_IN_GATE();
+       assert(fNotifyChildArray);
+       assert(fMachineState == kIOPM_NotifyChildrenDelayed);
+
+       // Wait after all non-delayed children and interested drivers have ack'ed,
+       // then notify all delayed children. If notify delay is canceled, child
+       // acks may be outstanding with PM blocked on fHeadNotePendingAcks != 0.
+       // But the handling for either case is identical.
+
+       for (int i = 0;; i++) {
+               connection = (IOPowerConnection *) fNotifyChildArray->getObject(i);
+               if (!connection) {
+                       break;
+               }
+
+               notifyChild( connection );
+       }
+
+       PM_LOG2("%s: notified delayed children\n", getName());
+       fNotifyChildArray->release();
+       fNotifyChildArray = NULL;
+
+       MS_POP(); // pushed by notifyChildren()
+}
+
+//*********************************************************************************
+// [private] notifyAll
+//*********************************************************************************
+
+IOReturn
+IOService::notifyAll( uint32_t nextMS )
+{
+       // Save the machine state to be restored by notifyInterestedDriversDone()
+
+       PM_ASSERT_IN_GATE();
+       MS_PUSH(nextMS);
+       fMachineState     = kIOPM_DriverThreadCallDone;
+       fDriverCallReason = fIsPreChange ?
+           kDriverCallInformPreChange : kDriverCallInformPostChange;
+
+       if (!notifyInterestedDrivers()) {
+               notifyInterestedDriversDone();
+       }
+
+       return IOPMWillAckLater;
+}
+
+//*********************************************************************************
+// [private, static] pmDriverCallout
+//
+// Thread call context
+//*********************************************************************************
+
+IOReturn
+IOService::actionDriverCalloutDone(
+       OSObject * target,
+       void * arg0, void * arg1,
+       void * arg2, void * arg3 )
+{
+       IOServicePM * pwrMgt = (IOServicePM *) arg0;
+
+       assert( fDriverCallBusy );
+       fDriverCallBusy = false;
+
+       assert(gIOPMWorkQueue);
+       gIOPMWorkQueue->signalWorkAvailable();
+
+       return kIOReturnSuccess;
+}
+
+void
+IOService::pmDriverCallout( IOService * from )
+{
+       assert(from);
+       switch (from->fDriverCallReason) {
+       case kDriverCallSetPowerState:
+               from->driverSetPowerState();
+               break;
+
+       case kDriverCallInformPreChange:
+       case kDriverCallInformPostChange:
+               from->driverInformPowerChange();
+               break;
+
+       case kRootDomainInformPreChange:
+               getPMRootDomain()->willNotifyPowerChildren(from->fHeadNotePowerState);
+               break;
+
+       default:
+               panic("IOService::pmDriverCallout bad machine state %x",
+                   from->fDriverCallReason);
+       }
+
+       gIOPMWorkLoop->runAction(actionDriverCalloutDone,
+           /* target */ from,
+           /* arg0   */ (void *) from->pwrMgt );
+}
+
+//*********************************************************************************
+// [private] driverSetPowerState
+//
+// Thread call context
+//*********************************************************************************
+
+void
+IOService::driverSetPowerState( void )
+{
+       IOPMPowerStateIndex powerState;
+       DriverCallParam *   param;
+       IOPMDriverCallEntry callEntry;
+       AbsoluteTime        end;
+       IOReturn            result;
+       uint32_t            oldPowerState = getPowerState();
+
+       assert( fDriverCallBusy );
+       assert( fDriverCallParamPtr );
+       assert( fDriverCallParamCount == 1 );
+
+       param = (DriverCallParam *) fDriverCallParamPtr;
+       powerState = fHeadNotePowerState;
+
+       if (assertPMDriverCall(&callEntry, kIOPMDriverCallMethodSetPowerState)) {
+               OUR_PMLogFuncStart(kPMLogProgramHardware, (uintptr_t) this, powerState);
+               clock_get_uptime(&fDriverCallStartTime);
+               result = fControllingDriver->setPowerState( powerState, this );
+               clock_get_uptime(&end);
+               OUR_PMLogFuncEnd(kPMLogProgramHardware, (uintptr_t) this, (UInt32) result);
+
+               deassertPMDriverCall(&callEntry);
+
+               // Record the most recent max power state residency timings.
+               // Use with DeviceActiveTimestamp to diagnose tickle issues.
+               if (powerState == fHighestPowerState) {
+                       fMaxPowerStateEntryTime = end;
+               } else if (oldPowerState == fHighestPowerState) {
+                       fMaxPowerStateExitTime = end;
+               }
+
+               if (result < 0) {
+                       PM_LOG("%s::setPowerState(%p, %lu -> %lu) returned 0x%x\n",
+                           fName, OBFUSCATE(this), fCurrentPowerState, powerState, result);
+               }
+
+
+               if ((result == IOPMAckImplied) || (result < 0)) {
+                       uint64_t    nsec;
+
+                       SUB_ABSOLUTETIME(&end, &fDriverCallStartTime);
+                       absolutetime_to_nanoseconds(end, &nsec);
+                       if (nsec > LOG_SETPOWER_TIMES) {
+                               getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                       gIOPMStatsDriverPSChangeSlow,
+                                       fName, kDriverCallSetPowerState, NS_TO_MS(nsec), getRegistryEntryID(),
+                                       NULL, powerState);
+                       }
+               }
+       } else {
+               result = kIOPMAckImplied;
+       }
+
+       param->Result = result;
+}
+
+//*********************************************************************************
+// [private] driverInformPowerChange
+//
+// Thread call context
+//*********************************************************************************
+
+void
+IOService::driverInformPowerChange( void )
+{
+       IOPMinformee *      informee;
+       IOService *         driver;
+       DriverCallParam *   param;
+       IOPMDriverCallEntry callEntry;
+       IOPMPowerFlags      powerFlags;
+       IOPMPowerStateIndex powerState;
+       AbsoluteTime        end;
+       IOReturn            result;
+       IOItemCount         count;
+       IOOptionBits        callMethod = (fDriverCallReason == kDriverCallInformPreChange) ?
+           kIOPMDriverCallMethodWillChange : kIOPMDriverCallMethodDidChange;
+
+       assert( fDriverCallBusy );
+       assert( fDriverCallParamPtr );
+       assert( fDriverCallParamCount );
+
+       param = (DriverCallParam *) fDriverCallParamPtr;
+       count = fDriverCallParamCount;
+
+       powerFlags = fHeadNotePowerArrayEntry->capabilityFlags;
+       powerState = fHeadNotePowerState;
+
+       for (IOItemCount i = 0; i < count; i++) {
+               informee = (IOPMinformee *) param->Target;
+               driver   = informee->whatObject;
+
+               if (assertPMDriverCall(&callEntry, callMethod, informee)) {
+                       if (fDriverCallReason == kDriverCallInformPreChange) {
+                               OUR_PMLogFuncStart(kPMLogInformDriverPreChange, (uintptr_t) this, powerState);
+                               clock_get_uptime(&informee->startTime);
+                               result = driver->powerStateWillChangeTo(powerFlags, powerState, this);
+                               clock_get_uptime(&end);
+                               OUR_PMLogFuncEnd(kPMLogInformDriverPreChange, (uintptr_t) this, result);
+                       } else {
+                               OUR_PMLogFuncStart(kPMLogInformDriverPostChange, (uintptr_t) this, powerState);
+                               clock_get_uptime(&informee->startTime);
+                               result = driver->powerStateDidChangeTo(powerFlags, powerState, this);
+                               clock_get_uptime(&end);
+                               OUR_PMLogFuncEnd(kPMLogInformDriverPostChange, (uintptr_t) this, result);
+                       }
+
+                       deassertPMDriverCall(&callEntry);
+
+
+                       if ((result == IOPMAckImplied) || (result < 0)) {
+                               uint64_t nsec;
+
+                               SUB_ABSOLUTETIME(&end, &informee->startTime);
+                               absolutetime_to_nanoseconds(end, &nsec);
+                               if (nsec > LOG_SETPOWER_TIMES) {
+                                       getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                               gIOPMStatsDriverPSChangeSlow, driver->getName(),
+                                               fDriverCallReason, NS_TO_MS(nsec), driver->getRegistryEntryID(),
+                                               NULL, powerState);
+                               }
+                       }
+               } else {
+                       result = kIOPMAckImplied;
+               }
+
+               param->Result = result;
+               param++;
+       }
+}
+
+//*********************************************************************************
+// [private] notifyChild
+//
+// Notify a power domain child of an upcoming power change.
+// If the object acknowledges the current change, we return TRUE.
+//*********************************************************************************
+
+bool
+IOService::notifyChild( IOPowerConnection * theNub )
+{
+       IOReturn                ret = IOPMAckImplied;
+       unsigned long           childPower;
+       IOService *             theChild;
+       IOPMRequest *           childRequest;
+       IOPMPowerChangeFlags    requestArg2;
+       int                     requestType;
+
+       PM_ASSERT_IN_GATE();
+       theChild = (IOService *)(theNub->copyChildEntry(gIOPowerPlane));
+       if (!theChild) {
+               return true;
+       }
+
+       // Unless the child handles the notification immediately and returns
+       // kIOPMAckImplied, we'll be awaiting their acknowledgement later.
+       fHeadNotePendingAcks++;
+       theNub->setAwaitingAck(true);
+
+       requestArg2 = fHeadNoteChangeFlags;
+       if (StateOrder(fHeadNotePowerState) < StateOrder(fCurrentPowerState)) {
+               requestArg2 |= kIOPMDomainPowerDrop;
+       }
+
+       requestType = fIsPreChange ?
+           kIOPMRequestTypePowerDomainWillChange :
+           kIOPMRequestTypePowerDomainDidChange;
+
+       childRequest = acquirePMRequest( theChild, requestType );
+       if (childRequest) {
+               theNub->retain();
+               childRequest->fArg0 = (void *) fHeadNotePowerArrayEntry->outputPowerFlags;
+               childRequest->fArg1 = (void *) theNub;
+               childRequest->fArg2 = (void *)(uintptr_t) requestArg2;
+               theChild->submitPMRequest( childRequest );
+               ret = IOPMWillAckLater;
+       } else {
+               ret = IOPMAckImplied;
+               fHeadNotePendingAcks--;
+               theNub->setAwaitingAck(false);
+               childPower = theChild->currentPowerConsumption();
+               if (childPower == kIOPMUnknown) {
+                       fHeadNotePowerArrayEntry->staticPower = kIOPMUnknown;
+               } else {
+                       if (fHeadNotePowerArrayEntry->staticPower != kIOPMUnknown) {
+                               fHeadNotePowerArrayEntry->staticPower += childPower;
+                       }
+               }
+       }
+
+       theChild->release();
+       return IOPMAckImplied == ret;
+}
+
+//*********************************************************************************
+// [private] notifyControllingDriver
+//*********************************************************************************
+
+bool
+IOService::notifyControllingDriver( void )
+{
+       DriverCallParam *   param;
+
+       PM_ASSERT_IN_GATE();
+       assert( fDriverCallParamCount == 0  );
+       assert( fControllingDriver );
+
+       if (fInitialSetPowerState) {
+               fInitialSetPowerState = false;
+               fHeadNoteChangeFlags |= kIOPMInitialPowerChange;
+
+               // Driver specified flag to skip the inital setPowerState()
+               if (fHeadNotePowerArrayEntry->capabilityFlags & kIOPMInitialDeviceState) {
+                       return false;
+               }
+       }
+
+       param = (DriverCallParam *) fDriverCallParamPtr;
+       if (!param) {
+               param = IONew(DriverCallParam, 1);
+               if (!param) {
+                       return false; // no memory
+               }
+               fDriverCallParamPtr   = (void *) param;
+               fDriverCallParamSlots = 1;
+       }
+
+       param->Target = fControllingDriver;
+       fDriverCallParamCount = 1;
+       fDriverTimer = -1;
+
+       // Block state machine and wait for callout completion.
+       assert(!fDriverCallBusy);
+       fDriverCallBusy = true;
+       thread_call_enter( fDriverCallEntry );
+
+       return true;
+}
+
+//*********************************************************************************
+// [private] notifyControllingDriverDone
+//*********************************************************************************
+
+void
+IOService::notifyControllingDriverDone( void )
+{
+       DriverCallParam *   param;
+       IOReturn            result;
+
+       PM_ASSERT_IN_GATE();
+       param = (DriverCallParam *) fDriverCallParamPtr;
+
+       assert( fDriverCallBusy == false );
+       assert( fMachineState == kIOPM_DriverThreadCallDone );
+
+       if (param && fDriverCallParamCount) {
+               assert(fDriverCallParamCount == 1);
+
+               // the return value from setPowerState()
+               result = param->Result;
+
+               if ((result == IOPMAckImplied) || (result < 0)) {
+                       fDriverTimer = 0;
+               } else if (fDriverTimer) {
+                       assert(fDriverTimer == -1);
+
+                       // Driver has not acked, and has returned a positive result.
+                       // Enforce a minimum permissible timeout value.
+                       // Make the min value large enough so timeout is less likely
+                       // to occur if a driver misinterpreted that the return value
+                       // should be in microsecond units.  And make it large enough
+                       // to be noticeable if a driver neglects to ack.
+
+                       if (result < kMinAckTimeoutTicks) {
+                               result = kMinAckTimeoutTicks;
+                       }
+
+                       fDriverTimer = (result / (ACK_TIMER_PERIOD / ns_per_us)) + 1;
+               }
+               // else, child has already acked and driver_timer reset to 0.
+
+               fDriverCallParamCount = 0;
+
+               if (fDriverTimer) {
+                       OUR_PMLog(kPMLogStartAckTimer, 0, 0);
+                       start_ack_timer();
+                       getPMRootDomain()->reset_watchdog_timer(this, result / USEC_PER_SEC + 1);
+               }
+       }
+
+       MS_POP(); // pushed by OurChangeSetPowerState()
+       fIsPreChange  = false;
+}
+
+//*********************************************************************************
+// [private] all_done
+//
+// A power change is done.
+//*********************************************************************************
+
+void
+IOService::all_done( void )
+{
+       IOPMPowerStateIndex     prevPowerState;
+       const IOPMPSEntry *     powerStatePtr;
+       IOPMDriverCallEntry     callEntry;
+       uint32_t                prevMachineState = fMachineState;
+       bool                    actionCalled = false;
+       uint64_t                ts;
+
+       fMachineState = kIOPM_Finished;
+
+       if ((fHeadNoteChangeFlags & kIOPMSynchronize) &&
+           ((prevMachineState == kIOPM_Finished) ||
+           (prevMachineState == kIOPM_SyncFinish))) {
+               // Sync operation and no power change occurred.
+               // Do not inform driver and clients about this request completion,
+               // except for the originator (root domain).
+
+               PM_ACTION_2(actionPowerChangeDone,
+                   fHeadNotePowerState, fHeadNoteChangeFlags);
+
+               if (getPMRequestType() == kIOPMRequestTypeSynchronizePowerTree) {
+                       powerChangeDone(fCurrentPowerState);
+               } else if (fAdvisoryTickleUsed) {
+                       // Not root domain and advisory tickle target.
+                       // Re-adjust power after power tree sync at the 'did' pass
+                       // to recompute desire and adjust power state between dark
+                       // and full wake transitions. Root domain is responsible
+                       // for calling setAdvisoryTickleEnable() before starting
+                       // the kIOPMSynchronize power change.
+
+                       if (!fAdjustPowerScheduled &&
+                           (fHeadNoteChangeFlags & kIOPMDomainDidChange)) {
+                               IOPMRequest * request;
+                               request = acquirePMRequest( this, kIOPMRequestTypeAdjustPowerState );
+                               if (request) {
+                                       submitPMRequest( request );
+                                       fAdjustPowerScheduled = true;
+                               }
+                       }
+               }
+
+               return;
+       }
+
+       // our power change
+       if (fHeadNoteChangeFlags & kIOPMSelfInitiated) {
+               // power state changed
+               if ((fHeadNoteChangeFlags & kIOPMNotDone) == 0) {
+                       trackSystemSleepPreventers(
+                               fCurrentPowerState, fHeadNotePowerState, fHeadNoteChangeFlags);
+
+                       // we changed, tell our parent
+                       requestDomainPower(fHeadNotePowerState);
+
+                       // yes, did power raise?
+                       if (StateOrder(fCurrentPowerState) < StateOrder(fHeadNotePowerState)) {
+                               // yes, inform clients and apps
+                               tellChangeUp(fHeadNotePowerState);
+                       }
+                       prevPowerState = fCurrentPowerState;
+                       // either way
+                       fCurrentPowerState = fHeadNotePowerState;
+                       PM_LOCK();
+                       if (fReportBuf) {
+                               ts = mach_absolute_time();
+                               STATEREPORT_SETSTATE(fReportBuf, fCurrentPowerState, ts);
+                       }
+                       PM_UNLOCK();
+#if PM_VARS_SUPPORT
+                       fPMVars->myCurrentState = fCurrentPowerState;
+#endif
+                       OUR_PMLog(kPMLogChangeDone, fCurrentPowerState, prevPowerState);
+                       PM_ACTION_2(actionPowerChangeDone,
+                           fHeadNotePowerState, fHeadNoteChangeFlags);
+                       actionCalled = true;
+
+                       powerStatePtr = &fPowerStates[fCurrentPowerState];
+                       fCurrentCapabilityFlags = powerStatePtr->capabilityFlags;
+                       if (fCurrentCapabilityFlags & kIOPMStaticPowerValid) {
+                               fCurrentPowerConsumption = powerStatePtr->staticPower;
+                       }
+
+                       if (fHeadNoteChangeFlags & kIOPMRootChangeDown) {
+                               // Bump tickle generation count once the entire tree is down
+                               gIOPMTickleGeneration++;
+                       }
+
+                       // inform subclass policy-maker
+                       if (fPCDFunctionOverride && fParentsKnowState &&
+                           assertPMDriverCall(&callEntry, kIOPMDriverCallMethodChangeDone, NULL, kIOPMDriverCallNoInactiveCheck)) {
+                               powerChangeDone(prevPowerState);
+                               deassertPMDriverCall(&callEntry);
+                       }
+               } else if (getPMRequestType() == kIOPMRequestTypeRequestPowerStateOverride) {
+                       // changePowerStateWithOverrideTo() was cancelled
+                       fOverrideMaxPowerState = kIOPMPowerStateMax;
+               }
+       }
+
+       // parent-initiated power change
+       if (fHeadNoteChangeFlags & kIOPMParentInitiated) {
+               if (fHeadNoteChangeFlags & kIOPMRootChangeDown) {
+                       ParentChangeRootChangeDown();
+               }
+
+               // power state changed
+               if ((fHeadNoteChangeFlags & kIOPMNotDone) == 0) {
+                       trackSystemSleepPreventers(
+                               fCurrentPowerState, fHeadNotePowerState, fHeadNoteChangeFlags);
+
+                       // did power raise?
+                       if (StateOrder(fCurrentPowerState) < StateOrder(fHeadNotePowerState)) {
+                               // yes, inform clients and apps
+                               tellChangeUp(fHeadNotePowerState);
+                       }
+                       // either way
+                       prevPowerState = fCurrentPowerState;
+                       fCurrentPowerState = fHeadNotePowerState;
+                       PM_LOCK();
+                       if (fReportBuf) {
+                               ts = mach_absolute_time();
+                               STATEREPORT_SETSTATE(fReportBuf, fCurrentPowerState, ts);
+                       }
+                       PM_UNLOCK();
+#if PM_VARS_SUPPORT
+                       fPMVars->myCurrentState = fCurrentPowerState;
+#endif
+
+                       OUR_PMLog(kPMLogChangeDone, fCurrentPowerState, prevPowerState);
+                       PM_ACTION_2(actionPowerChangeDone,
+                           fHeadNotePowerState, fHeadNoteChangeFlags);
+                       actionCalled = true;
+
+                       powerStatePtr = &fPowerStates[fCurrentPowerState];
+                       fCurrentCapabilityFlags = powerStatePtr->capabilityFlags;
+                       if (fCurrentCapabilityFlags & kIOPMStaticPowerValid) {
+                               fCurrentPowerConsumption = powerStatePtr->staticPower;
+                       }
+
+                       // inform subclass policy-maker
+                       if (fPCDFunctionOverride && fParentsKnowState &&
+                           assertPMDriverCall(&callEntry, kIOPMDriverCallMethodChangeDone, NULL, kIOPMDriverCallNoInactiveCheck)) {
+                               powerChangeDone(prevPowerState);
+                               deassertPMDriverCall(&callEntry);
+                       }
+               }
+       }
+
+       // When power rises enough to satisfy the tickle's desire for more power,
+       // the condition preventing idle-timer from dropping power is removed.
+
+       if (StateOrder(fCurrentPowerState) >= StateOrder(fIdleTimerMinPowerState)) {
+               fIdleTimerMinPowerState = kPowerStateZero;
+       }
+
+       if (!actionCalled) {
+               PM_ACTION_2(actionPowerChangeDone,
+                   fHeadNotePowerState, fHeadNoteChangeFlags);
+       }
+}
+
+// MARK: -
+// MARK: Power Change Initiated by Driver
+
+//*********************************************************************************
+// [private] OurChangeStart
+//
+// Begin the processing of a power change initiated by us.
+//*********************************************************************************
+
+void
+IOService::OurChangeStart( void )
+{
+       PM_ASSERT_IN_GATE();
+       OUR_PMLog( kPMLogStartDeviceChange, fHeadNotePowerState, fCurrentPowerState );
+
+       // fMaxPowerState is our maximum possible power state based on the current
+       // power state of our parents.  If we are trying to raise power beyond the
+       // maximum, send an async request for more power to all parents.
+
+       if (!IS_PM_ROOT && (StateOrder(fMaxPowerState) < StateOrder(fHeadNotePowerState))) {
+               fHeadNoteChangeFlags |= kIOPMNotDone;
+               requestDomainPower(fHeadNotePowerState);
+               OurChangeFinish();
+               return;
+       }
+
+       // Redundant power changes skips to the end of the state machine.
+
+       if (!fInitialPowerChange && (fHeadNotePowerState == fCurrentPowerState)) {
+               OurChangeFinish();
+               return;
+       }
+       fInitialPowerChange = false;
+
+       // Change started, but may not complete...
+       // Can be canceled (power drop) or deferred (power rise).
+
+       PM_ACTION_2(actionPowerChangeStart, fHeadNotePowerState, &fHeadNoteChangeFlags);
+
+       // Two separate paths, depending if power is being raised or lowered.
+       // Lowering power is subject to approval by clients of this service.
+
+       if (IS_POWER_DROP) {
+               fDoNotPowerDown = false;
+
+               // Ask for persmission to drop power state
+               fMachineState = kIOPM_OurChangeTellClientsPowerDown;
+               fOutOfBandParameter = kNotifyApps;
+               askChangeDown(fHeadNotePowerState);
+       } else {
+               // This service is raising power and parents are able to support the
+               // new power state. However a parent may have already committed to
+               // drop power, which might force this object to temporarily drop power.
+               // This results in "oscillations" before the state machines converge
+               // to a steady state.
+               //
+               // To prevent this, a child must make a power reservation against all
+               // parents before raising power. If the reservation fails, indicating
+               // that the child will be unable to sustain the higher power state,
+               // then the child will signal the parent to adjust power, and the child
+               // will defer its power change.
+
+               IOReturn ret;
+
+               // Reserve parent power necessary to achieve fHeadNotePowerState.
+               ret = requestDomainPower( fHeadNotePowerState, kReserveDomainPower );
+               if (ret != kIOReturnSuccess) {
+                       // Reservation failed, defer power rise.
+                       fHeadNoteChangeFlags |= kIOPMNotDone;
+                       OurChangeFinish();
+                       return;
+               }
+
+               OurChangeTellCapabilityWillChange();
+       }
+}
+
+//*********************************************************************************
+// [private] requestDomainPowerApplier
+//
+// Call requestPowerDomainState() on all power parents.
+//*********************************************************************************
+
+struct IOPMRequestDomainPowerContext {
+       IOService *     child;          // the requesting child
+       IOPMPowerFlags  requestPowerFlags;// power flags requested by child
+};
+
+static void
+requestDomainPowerApplier(
+       IORegistryEntry *   entry,
+       void *              inContext )
+{
+       IOPowerConnection *             connection;
+       IOService *                     parent;
+       IOPMRequestDomainPowerContext * context;
+
+       if ((connection = OSDynamicCast(IOPowerConnection, entry)) == NULL) {
+               return;
+       }
+       parent = (IOService *) connection->copyParentEntry(gIOPowerPlane);
+       if (!parent) {
+               return;
+       }
+
+       assert(inContext);
+       context = (IOPMRequestDomainPowerContext *) inContext;
+
+       if (connection->parentKnowsState() && connection->getReadyFlag()) {
+               parent->requestPowerDomainState(
+                       context->requestPowerFlags,
+                       connection,
+                       IOPMLowestState);
+       }
+
+       parent->release();
+}
+
+//*********************************************************************************
+// [private] requestDomainPower
+//
+// Called by a power child to broadcast its desired power state to all parents.
+// If the child self-initiates a power change, it must call this function to
+// allow its parents to adjust power state.
+//*********************************************************************************
+
+IOReturn
+IOService::requestDomainPower(
+       IOPMPowerStateIndex ourPowerState,
+       IOOptionBits        options )
+{
+       IOPMPowerFlags                  requestPowerFlags;
+       IOPMPowerStateIndex             maxPowerState;
+       IOPMRequestDomainPowerContext   context;
+
+       PM_ASSERT_IN_GATE();
+       assert(ourPowerState < fNumberOfPowerStates);
+       if (ourPowerState >= fNumberOfPowerStates) {
+               return kIOReturnBadArgument;
+       }
+       if (IS_PM_ROOT) {
+               return kIOReturnSuccess;
+       }
+
+       // Fetch our input power flags for the requested power state.
+       // Parent request is stated in terms of required power flags.
+
+       requestPowerFlags = fPowerStates[ourPowerState].inputPowerFlags;
+
+       // Disregard the "previous request" for power reservation.
+
+       if (((options & kReserveDomainPower) == 0) &&
+           (fPreviousRequestPowerFlags == requestPowerFlags)) {
+               // skip if domain already knows our requirements
+               goto done;
+       }
+       fPreviousRequestPowerFlags = requestPowerFlags;
+
+       // The results will be collected by fHeadNoteDomainTargetFlags
+       context.child              = this;
+       context.requestPowerFlags  = requestPowerFlags;
+       fHeadNoteDomainTargetFlags = 0;
+       applyToParents(requestDomainPowerApplier, &context, gIOPowerPlane);
+
+       if (options & kReserveDomainPower) {
+               maxPowerState = fControllingDriver->maxCapabilityForDomainState(
+                       fHeadNoteDomainTargetFlags );
+
+               if (StateOrder(maxPowerState) < StateOrder(ourPowerState)) {
+                       PM_LOG1("%s: power desired %u:0x%x got %u:0x%x\n",
+                           getName(),
+                           (uint32_t) ourPowerState, (uint32_t) requestPowerFlags,
+                           (uint32_t) maxPowerState, (uint32_t) fHeadNoteDomainTargetFlags);
+                       return kIOReturnNoPower;
+               }
+       }
+
+done:
+       return kIOReturnSuccess;
+}
+
+//*********************************************************************************
+// [private] OurSyncStart
+//*********************************************************************************
+
+void
+IOService::OurSyncStart( void )
+{
+       PM_ASSERT_IN_GATE();
+
+       if (fInitialPowerChange) {
+               return;
+       }
+
+       PM_ACTION_2(actionPowerChangeStart, fHeadNotePowerState, &fHeadNoteChangeFlags);
+
+       if (fHeadNoteChangeFlags & kIOPMNotDone) {
+               OurChangeFinish();
+               return;
+       }
+
+       if (fHeadNoteChangeFlags & kIOPMSyncTellPowerDown) {
+               fDoNotPowerDown = false;
+
+               // Ask for permission to drop power state
+               fMachineState = kIOPM_SyncTellClientsPowerDown;
+               fOutOfBandParameter = kNotifyApps;
+               askChangeDown(fHeadNotePowerState);
+       } else {
+               // Only inform capability app and clients.
+               tellSystemCapabilityChange( kIOPM_SyncNotifyWillChange );
+       }
+}
+
+//*********************************************************************************
+// [private] OurChangeTellClientsPowerDown
+//
+// All applications and kernel clients have acknowledged our permission to drop
+// power. Here we notify them that we will lower the power and wait for acks.
+//*********************************************************************************
+
+void
+IOService::OurChangeTellClientsPowerDown( void )
+{
+       if (!IS_ROOT_DOMAIN) {
+               fMachineState = kIOPM_OurChangeTellPriorityClientsPowerDown;
+       } else {
+               fMachineState = kIOPM_OurChangeTellUserPMPolicyPowerDown;
+       }
+       tellChangeDown1(fHeadNotePowerState);
+}
+
+//*********************************************************************************
+// [private] OurChangeTellUserPMPolicyPowerDown
+//
+// All applications and kernel clients have acknowledged our permission to drop
+// power. Here we notify power management policy in user-space and wait for acks
+// one last time before we lower power
+//*********************************************************************************
+void
+IOService::OurChangeTellUserPMPolicyPowerDown( void )
+{
+       fMachineState = kIOPM_OurChangeTellPriorityClientsPowerDown;
+       fOutOfBandParameter = kNotifyApps;
+
+       tellClientsWithResponse(kIOPMMessageLastCallBeforeSleep);
+}
+
+//*********************************************************************************
+// [private] OurChangeTellPriorityClientsPowerDown
+//
+// All applications and kernel clients have acknowledged our intention to drop
+// power.  Here we notify "priority" clients that we are lowering power.
+//*********************************************************************************
 
-    // no, return current capability
-    return  pm_vars->thePowerStates[pm_vars->myCurrentState].capabilityFlags;  
+void
+IOService::OurChangeTellPriorityClientsPowerDown( void )
+{
+       fMachineState = kIOPM_OurChangeNotifyInterestedDriversWillChange;
+       tellChangeDown2(fHeadNotePowerState);
 }
 
-
 //*********************************************************************************
-// deRegisterInterestedDriver
+// [private] OurChangeTellCapabilityWillChange
 //
+// Extra stage for root domain to notify apps and drivers about the
+// system capability change when raising power state.
 //*********************************************************************************
-IOReturn IOService::deRegisterInterestedDriver ( IOService * theDriver )
-{
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogRemoveDriver,0,0);
 
-    // remove the departing driver
-    priv->interestedDrivers->removeFromList(theDriver);
+void
+IOService::OurChangeTellCapabilityWillChange( void )
+{
+       if (!IS_ROOT_DOMAIN) {
+               return OurChangeNotifyInterestedDriversWillChange();
+       }
 
-    return IOPMNoErr;
+       tellSystemCapabilityChange( kIOPM_OurChangeNotifyInterestedDriversWillChange );
 }
 
-
 //*********************************************************************************
-// acknowledgePowerChange
+// [private] OurChangeNotifyInterestedDriversWillChange
 //
-// After we notified one of the interested drivers or a power-domain child
-// of an impending change in power, it has called to say it is now
-// prepared for the change.  If this object is the last to
-// acknowledge this change, we take whatever action we have been waiting
-// for.
-// That may include acknowledging to our parent.  In this case, we do it
-// last of all to insure that this doesn't cause the parent to call us some-
-// where else and alter data we are relying on here (like the very existance
-// of a "current change note".)
+// All applications and kernel clients have acknowledged our power state change.
+// Here we notify interested drivers pre-change.
 //*********************************************************************************
 
-IOReturn IOService::acknowledgePowerChange ( IOService * whichObject )
-{
-    IOPMinformee                                *ackingObject;
-    unsigned long                                  childPower = kIOPMUnknown;
-    IOService                                   *theChild;
-
-    // one of our interested drivers?
-    ackingObject =  priv->interestedDrivers->findItem(whichObject);
-    if ( ackingObject == NULL ) 
-    {
-        if ( ! isChild(whichObject,gIOPowerPlane) ) 
-        {
-             pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAcknowledgeErr1,0,0);
-             //kprintf("errant driver: %s\n",whichObject->getName());
-             // no, just return
-            return IOPMNoErr;
-        } else {
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogChildAcknowledge,priv->head_note_pendingAcks,0);
-        }
-    } else {
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogDriverAcknowledge,priv->head_note_pendingAcks,0);
-    }
-    if (! acquire_lock() ) 
-    {
-        return IOPMNoErr;
-    }
-    if (priv->head_note_pendingAcks != 0 ) 
-    {
-         // yes, make sure we're expecting acks
-        if ( ackingObject != NULL ) 
-        {
-            // it's an interested driver
-            // make sure we're expecting this ack
-            if ( ackingObject->timer != 0 ) 
-            {
-                // mark it acked
-                ackingObject->timer = 0;
-                // that's one fewer to worry about
-                priv->head_note_pendingAcks -= 1;
-                // is that the last?
-                if ( priv->head_note_pendingAcks == 0 ) 
-                {
-                    // yes, stop the timer
-                    stop_ack_timer();
-                    IOUnlock(priv->our_lock);
-                    // and now we can continue
-                    all_acked();
-                    return IOPMNoErr;
-                }
-            } else {
-                // this driver has already acked
-                pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAcknowledgeErr2,0,0);
-                //kprintf("errant driver: %s\n",whichObject->getName());
-            }
-        } else {
-            // it's a child
-            // make sure we're expecting this ack
-            if ( ((IOPowerConnection *)whichObject)->getAwaitingAck() ) 
-            {
-                // that's one fewer to worry about
-                priv->head_note_pendingAcks -= 1;
-                ((IOPowerConnection *)whichObject)->setAwaitingAck(false);
-                theChild = (IOService *)whichObject->copyChildEntry(gIOPowerPlane);
-                if ( theChild ) 
-                {
-                    childPower = theChild->currentPowerConsumption();
-                    theChild->release();
-                }
-                if ( childPower == kIOPMUnknown ) 
-                {
-                    pm_vars->thePowerStates[priv->head_note_state].staticPower = kIOPMUnknown;
-                } else {
-                    if ( pm_vars->thePowerStates[priv->head_note_state].staticPower != kIOPMUnknown ) 
-                    {
-                        pm_vars->thePowerStates[priv->head_note_state].staticPower += childPower;
-                    }
-                }
-                // is that the last?
-                if ( priv->head_note_pendingAcks == 0 ) {
-                    // yes, stop the timer
-                    stop_ack_timer();
-                    IOUnlock(priv->our_lock);
-                    // and now we can continue
-                    all_acked();
-                    return IOPMNoErr;
-                }
-            }
-           }
-    } else {
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAcknowledgeErr3,0,0);        // not expecting anybody to ack
-        //kprintf("errant driver: %s\n",whichObject->getName());
-    }
-    IOUnlock(priv->our_lock);
-    return IOPMNoErr;
-}
-
-//*********************************************************************************
-// acknowledgeSetPowerState
+void
+IOService::OurChangeNotifyInterestedDriversWillChange( void )
+{
+       IOPMrootDomain * rootDomain;
+       if ((rootDomain = getPMRootDomain()) == this) {
+               if (IS_POWER_DROP) {
+                       rootDomain->tracePoint( kIOPMTracePointSleepWillChangeInterests );
+               } else {
+                       rootDomain->tracePoint( kIOPMTracePointWakeWillChangeInterests );
+               }
+       }
+
+       notifyAll( kIOPM_OurChangeSetPowerState );
+}
+
+//*********************************************************************************
+// [private] OurChangeSetPowerState
 //
-// After we instructed our controlling driver to change power states,
-// it has called to say it has finished doing so.
-// We continue to process the power state change.
+// Instruct our controlling driver to program the hardware for the power state
+// change. Wait for async completions.
 //*********************************************************************************
 
-IOReturn IOService::acknowledgeSetPowerState ( void )
+void
+IOService::OurChangeSetPowerState( void )
 {
-    if (! acquire_lock() ) 
-    {
-        return IOPMNoErr;
-    }
-
-    ioSPMTrace(IOPOWER_ACK, * (int *) this);
+       MS_PUSH( kIOPM_OurChangeWaitForPowerSettle );
+       fMachineState     = kIOPM_DriverThreadCallDone;
+       fDriverCallReason = kDriverCallSetPowerState;
 
-    if ( priv->driver_timer == -1 ) 
-    {
-        // driver is acking instead of using return code
-        priv->driver_timer = 0;
-    } else {
-        // are we expecting this?
-        if ( priv->driver_timer > 0 ) 
-        {
-            // yes, stop the timer
-            stop_ack_timer();
-            priv->driver_timer = 0;
-            IOUnlock(priv->our_lock);
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogDriverAcknowledgeSet,0,0);
-            driver_acked();
-            return IOPMNoErr;
-        } else {
-            // not expecting this
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAcknowledgeErr4,0,0);
-        }
-    }
-    IOUnlock(priv->our_lock);
-    return IOPMNoErr;
+       if (notifyControllingDriver() == false) {
+               notifyControllingDriverDone();
+       }
 }
 
-
 //*********************************************************************************
-// driver_acked
+// [private] OurChangeWaitForPowerSettle
 //
-// Either the controlling driver has called acknowledgeSetPowerState
-// or the acknowledgement timer has expired while waiting for that.
-// We carry on processing the current change note.
+// Our controlling driver has completed the power state change we initiated.
+// Wait for the driver specified settle time to expire.
 //*********************************************************************************
 
-void IOService::driver_acked ( void )
+void
+IOService::OurChangeWaitForPowerSettle( void )
 {
-    switch (priv->machine_state) {
-        case kIOPM_OurChangeWaitForPowerSettle:
-            OurChangeWaitForPowerSettle();
-            break;
-        case kIOPM_ParentDownWaitForPowerSettle_Delayed:
-            ParentDownWaitForPowerSettle_Delayed();
-            break;
-        case kIOPM_ParentUpWaitForSettleTime_Delayed:
-            ParentUpWaitForSettleTime_Delayed();
-            break;
-    }
+       fMachineState = kIOPM_OurChangeNotifyInterestedDriversDidChange;
+       startSettleTimer();
 }
 
-
 //*********************************************************************************
-// powerDomainWillChangeTo
+// [private] OurChangeNotifyInterestedDriversDidChange
 //
-// Called by the power-hierarchy parent notifying of a new power state
-// in the power domain.
-// We enqueue a parent power-change to our queue of power changes.
-// This may or may not cause us to change power, depending on what
-// kind of change is occuring in the domain.
+// Power has settled on a power change we initiated. Here we notify
+// all our interested drivers post-change.
 //*********************************************************************************
 
-IOReturn IOService::powerDomainWillChangeTo ( IOPMPowerFlags newPowerStateFlags, IOPowerConnection * whichParent )
-{
-    OSIterator                      *iter;
-    OSObject                        *next;
-    IOPowerConnection               *connection;
-    unsigned long                   newStateNumber;
-    IOPMPowerFlags                  combinedPowerFlags;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogWillChange,(unsigned long)newPowerStateFlags,0);
-
-    if ( ! inPlane(gIOPowerPlane) ) 
-    {
-        // somebody goofed
-        return IOPMAckImplied;
-    }
-
-    IOLockLock(pm_vars->parentLock);
-    
-    if ( (pm_vars->PMworkloop == NULL) || (pm_vars->PMcommandGate == NULL) ) 
-    {
-        // we have a path to the root
-        getPMworkloop();
-        // so find out the workloop
-        if ( pm_vars->PMworkloop != NULL ) 
-        {
-            // and make our command gate
-            if ( pm_vars->PMcommandGate == NULL ) 
-            {
-                pm_vars->PMcommandGate = IOCommandGate::commandGate((OSObject *)this);
-                if ( pm_vars->PMcommandGate != NULL ) 
-                {
-                    pm_vars->PMworkloop->addEventSource(pm_vars->PMcommandGate);
-                }
-            }
-        }
-    }
-    
-    IOLockUnlock(pm_vars->parentLock);
-
-    // combine parents' power states
-    // to determine our maximum state within the new power domain
-    combinedPowerFlags = 0;
-    
-    iter = getParentIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                if ( connection == whichParent ){
-                    combinedPowerFlags |= newPowerStateFlags;
-                } else {
-                    combinedPowerFlags |= connection->parentCurrentPowerFlags();
-                }
-            }
-        }
-        iter->release();
-    }
-    
-    if  ( pm_vars->theControllingDriver == NULL ) 
-    {
-        // we can't take any more action
-        return IOPMAckImplied;
-    }
-    newStateNumber = pm_vars->theControllingDriver->maxCapabilityForDomainState(combinedPowerFlags);
-    // make the change
-    return enqueuePowerChange(IOPMParentInitiated | IOPMDomainWillChange,
-                            newStateNumber,combinedPowerFlags,whichParent,newPowerStateFlags);
-}
-
-
-//*********************************************************************************
-// powerDomainDidChangeTo
+void
+IOService::OurChangeNotifyInterestedDriversDidChange( void )
+{
+       IOPMrootDomain * rootDomain;
+       if ((rootDomain = getPMRootDomain()) == this) {
+               rootDomain->tracePoint( IS_POWER_DROP ?
+                   kIOPMTracePointSleepDidChangeInterests :
+                   kIOPMTracePointWakeDidChangeInterests  );
+       }
+
+       notifyAll( kIOPM_OurChangeTellCapabilityDidChange );
+}
+
+//*********************************************************************************
+// [private] OurChangeTellCapabilityDidChange
 //
-// Called by the power-hierarchy parent after the power state of the power domain
-// has settled at a new level.
-// We enqueue a parent power-change to our queue of power changes.
-// This may or may not cause us to change power, depending on what
-// kind of change is occuring in the domain.
+// For root domain to notify capability power-change.
 //*********************************************************************************
 
-IOReturn IOService::powerDomainDidChangeTo ( IOPMPowerFlags newPowerStateFlags, IOPowerConnection * whichParent )
+void
+IOService::OurChangeTellCapabilityDidChange( void )
 {
-    unsigned long newStateNumber;
+       if (!IS_ROOT_DOMAIN) {
+               return OurChangeFinish();
+       }
 
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogDidChange,newPowerStateFlags,0);
+       getPMRootDomain()->tracePoint( IS_POWER_DROP ?
+           kIOPMTracePointSleepCapabilityClients :
+           kIOPMTracePointWakeCapabilityClients  );
 
-    setParentInfo(newPowerStateFlags,whichParent);
+       tellSystemCapabilityChange( kIOPM_OurChangeFinish );
+}
 
-    if ( pm_vars->theControllingDriver == NULL ) {
-        return IOPMAckImplied;
-    }
+//*********************************************************************************
+// [private] OurChangeFinish
+//
+// Done with this self-induced power state change.
+//*********************************************************************************
 
-    newStateNumber = pm_vars->theControllingDriver->maxCapabilityForDomainState(pm_vars->parentsCurrentPowerFlags);
-    // tell interested parties about it
-    return enqueuePowerChange(IOPMParentInitiated | IOPMDomainDidChange,
-                    newStateNumber,pm_vars->parentsCurrentPowerFlags,whichParent,0);
+void
+IOService::OurChangeFinish( void )
+{
+       all_done();
 }
 
+// MARK: -
+// MARK: Power Change Initiated by Parent
 
 //*********************************************************************************
-// setParentInfo
+// [private] ParentChangeStart
 //
-// Set our connection data for one specific parent, and then combine all the parent
-// data together.
+// Here we begin the processing of a power change initiated by our parent.
 //*********************************************************************************
 
-void IOService::setParentInfo ( IOPMPowerFlags newPowerStateFlags, IOPowerConnection * whichParent )
+IOReturn
+IOService::ParentChangeStart( void )
 {
-    OSIterator                      *iter;
-    OSObject                        *next;
-    IOPowerConnection               *connection;
-    
-    // set our connection data
-    whichParent->setParentCurrentPowerFlags(newPowerStateFlags);
-    whichParent->setParentKnowsState(true);
-
-    IOLockLock(pm_vars->parentLock);
-    
-    // recompute our parent info
-    pm_vars->parentsCurrentPowerFlags = 0;
-    pm_vars->parentsKnowState = true;
-
-    iter = getParentIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                pm_vars->parentsKnowState &= connection->parentKnowsState();
-                pm_vars->parentsCurrentPowerFlags |= connection->parentCurrentPowerFlags();
-            }
-        }
-        iter->release();
-    }
-    IOLockUnlock(pm_vars->parentLock);
-}
-
-//*********************************************************************************
-// rebuildChildClampBits
-//
-// The ChildClamp bits (kIOPMChildClamp & kIOPMChildClamp2) in our capabilityFlags
-// indicate that one of our children (or grandchildren or great-grandchildren or ...)
-// doesn't support idle or system sleep in its current state. Since we don't track the
-// origin of each bit, every time any child changes state we have to clear these bits 
-// and rebuild them.
-//*********************************************************************************
-
-void IOService::rebuildChildClampBits(void)
-{
-    unsigned long                       i;
-    OSIterator                          *iter;
-    OSObject                            *next;
-    IOPowerConnection                   *connection;
-    
-    
-    // A child's desires has changed.  We need to rebuild the child-clamp bits in our
-    // power state array.  Start by clearing the bits in each power state.
-    
-    for ( i = 0; i < pm_vars->theNumberOfPowerStates; i++ ) 
-    {
-        pm_vars->thePowerStates[i].capabilityFlags &= ~(kIOPMChildClamp | kIOPMChildClamp2);
-    }
-
-    // Now loop through the children.  When we encounter the calling child, save
-    // the computed state as this child's desire.  And while we're at it, set the ChildClamp bits
-    // in any of our states that some child has requested with clamp on.
-
-    iter = getChildIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                if ( connection->getPreventIdleSleepFlag() )
-                    pm_vars->thePowerStates[connection->getDesiredDomainState()].capabilityFlags |= kIOPMChildClamp;
-                if ( connection->getPreventSystemSleepFlag() )
-                    pm_vars->thePowerStates[connection->getDesiredDomainState()].capabilityFlags |= kIOPMChildClamp2;
-            }
-        }
-        iter->release();
-    }
-
-}
-
-
-//*********************************************************************************
-// requestPowerDomainState
-//
-// The kIOPMPreventIdleSleep and/or kIOPMPreventIdleSleep bits may be be set in the parameter.
-// It is not considered part of the state specification.
-//*********************************************************************************
-IOReturn IOService::requestPowerDomainState ( IOPMPowerFlags desiredState, IOPowerConnection * whichChild, unsigned long specification )
-{
-    unsigned long                           i;
-    unsigned long                           computedState;
-    unsigned long                           theDesiredState = desiredState & ~(kIOPMPreventIdleSleep | kIOPMPreventSystemSleep);
-    OSIterator                              *iter;
-    OSObject                                *next;
-    IOPowerConnection                       *connection;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogRequestDomain,
-                                (unsigned long)desiredState,(unsigned long)specification);
-
-    if ( pm_vars->theControllingDriver == NULL) 
-    {
-        return IOPMNotYetInitialized;
-    }
-
-    switch (specification) {
-        case IOPMLowestState:
-            i = 0;
-            while ( i < pm_vars->theNumberOfPowerStates ) 
-            {
-                if ( ( pm_vars->thePowerStates[i].outputPowerCharacter & theDesiredState) == (theDesiredState & pm_vars->myCharacterFlags) ) 
-                {
-                    break;
-                }
-                i++;
-            }
-            if ( i >= pm_vars->theNumberOfPowerStates ) 
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        case IOPMNextLowerState:
-            i = pm_vars->myCurrentState - 1;
-            while ( i >= 0 ) 
-            {
-                if ( ( pm_vars->thePowerStates[i].outputPowerCharacter & theDesiredState) == (theDesiredState & pm_vars->myCharacterFlags) ) 
-                {
-                    break;
-                }
-                i--;
-            }
-            if ( i < 0 ) 
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        case IOPMHighestState:
-            i = pm_vars->theNumberOfPowerStates;
-            while ( i >= 0 ) 
-            {
-                i--;
-                if ( ( pm_vars->thePowerStates[i].outputPowerCharacter & theDesiredState) == (theDesiredState & pm_vars->myCharacterFlags) ) 
-                {
-                    break;
-                }
-            }
-            if ( i < 0 ) 
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        case IOPMNextHigherState:
-            i = pm_vars->myCurrentState + 1;
-            while ( i < pm_vars->theNumberOfPowerStates ) 
-            {
-                if ( ( pm_vars->thePowerStates[i].outputPowerCharacter & theDesiredState) == (theDesiredState & pm_vars->myCharacterFlags) ) 
-                {
-                    break;
-                }
-                i++;
-            }
-            if ( i == pm_vars->theNumberOfPowerStates ) 
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        default:
-            return IOPMBadSpecification;
-    }
-
-    computedState = i;
-    
-    IOLockLock(pm_vars->childLock);
-
-    // Now loop through the children.  When we encounter the calling child, save
-    // the computed state as this child's desire.
-    iter = getChildIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                if ( connection == whichChild ) 
-                {
-                    connection->setDesiredDomainState(computedState);
-                    connection->setPreventIdleSleepFlag(desiredState & kIOPMPreventIdleSleep);
-                    connection->setPreventSystemSleepFlag(desiredState & kIOPMPreventSystemSleep);
-                    connection->setChildHasRequestedPower();
-                }
-            }
-        }
-        iter->release();
-    }
-
-    // Since a child's power requirements may have changed, clear and rebuild 
-    // kIOPMChildClamp and kIOPMChildClamp2 (idle and system sleep clamps)
-    rebuildChildClampBits();
-        
-    IOLockUnlock(pm_vars->childLock);
-    
-    // this may be different now
-    computeDesiredState();
-
-    if ( inPlane(gIOPowerPlane) &&
-         (pm_vars->parentsKnowState) ) {
-         // change state if all children can now tolerate lower power
-        changeState();
-    }
-   
-    // are we clamped on, waiting for this child?
-    if ( priv->clampOn ) {
-        // yes, remove the clamp
-        priv->clampOn = false;
-        changePowerStateToPriv(0);
-    }
-   
-   return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// temporaryPowerClampOn
+       PM_ASSERT_IN_GATE();
+       OUR_PMLog( kPMLogStartParentChange, fHeadNotePowerState, fCurrentPowerState );
+
+       // Root power domain has transitioned to its max power state
+       if ((fHeadNoteChangeFlags & (kIOPMDomainDidChange | kIOPMRootChangeUp)) ==
+           (kIOPMDomainDidChange | kIOPMRootChangeUp)) {
+               // Restart the idle timer stopped by ParentChangeRootChangeDown()
+               if (fIdleTimerPeriod && fIdleTimerStopped) {
+                       restartIdleTimer();
+               }
+       }
+
+       // Power domain is forcing us to lower power
+       if (StateOrder(fHeadNotePowerState) < StateOrder(fCurrentPowerState)) {
+               PM_ACTION_2(actionPowerChangeStart, fHeadNotePowerState, &fHeadNoteChangeFlags);
+
+               // Tell apps and kernel clients
+               fInitialPowerChange = false;
+               fMachineState = kIOPM_ParentChangeTellPriorityClientsPowerDown;
+               tellChangeDown1(fHeadNotePowerState);
+               return IOPMWillAckLater;
+       }
+
+       // Power domain is allowing us to raise power up to fHeadNotePowerState
+       if (StateOrder(fHeadNotePowerState) > StateOrder(fCurrentPowerState)) {
+               if (StateOrder(fDesiredPowerState) > StateOrder(fCurrentPowerState)) {
+                       if (StateOrder(fDesiredPowerState) < StateOrder(fHeadNotePowerState)) {
+                               // We power up, but not all the way
+                               fHeadNotePowerState = fDesiredPowerState;
+                               fHeadNotePowerArrayEntry = &fPowerStates[fDesiredPowerState];
+                               OUR_PMLog(kPMLogAmendParentChange, fHeadNotePowerState, 0);
+                       }
+               } else {
+                       // We don't need to change
+                       fHeadNotePowerState = fCurrentPowerState;
+                       fHeadNotePowerArrayEntry = &fPowerStates[fCurrentPowerState];
+                       OUR_PMLog(kPMLogAmendParentChange, fHeadNotePowerState, 0);
+               }
+       }
+
+       if (fHeadNoteChangeFlags & kIOPMDomainDidChange) {
+               if (StateOrder(fHeadNotePowerState) > StateOrder(fCurrentPowerState)) {
+                       PM_ACTION_2(actionPowerChangeStart,
+                           fHeadNotePowerState, &fHeadNoteChangeFlags);
+
+                       // Parent did change up - start our change up
+                       fInitialPowerChange = false;
+                       ParentChangeTellCapabilityWillChange();
+                       return IOPMWillAckLater;
+               } else if (fHeadNoteChangeFlags & kIOPMRootBroadcastFlags) {
+                       // No need to change power state, but broadcast change
+                       // to our children.
+                       fMachineState     = kIOPM_SyncNotifyDidChange;
+                       fDriverCallReason = kDriverCallInformPreChange;
+                       fHeadNoteChangeFlags |= kIOPMNotDone;
+                       notifyChildren();
+                       return IOPMWillAckLater;
+               }
+       }
+
+       // No power state change necessary
+       fHeadNoteChangeFlags |= kIOPMNotDone;
+
+       all_done();
+       return IOPMAckImplied;
+}
+
+//******************************************************************************
+// [private] ParentChangeRootChangeDown
 //
-// A power domain wants to clamp its power on till it has children which
-// will thendetermine the power domain state.
+// Root domain has finished the transition to the system sleep state. And all
+// drivers in the power plane should have powered down. Cancel the idle timer,
+// and also reset the device desire for those drivers that don't want power
+// automatically restored on wake.
+//******************************************************************************
+
+void
+IOService::ParentChangeRootChangeDown( void )
+{
+       // Always stop the idle timer before root power down
+       if (fIdleTimerPeriod && !fIdleTimerStopped) {
+               fIdleTimerStopped = true;
+               if (fIdleTimer && thread_call_cancel(fIdleTimer)) {
+                       release();
+               }
+       }
+
+       if (fResetPowerStateOnWake) {
+               // Reset device desire down to the lowest power state.
+               // Advisory tickle desire is intentionally untouched since
+               // it has no effect until system is promoted to full wake.
+
+               if (fDeviceDesire != kPowerStateZero) {
+                       updatePowerClient(gIOPMPowerClientDevice, kPowerStateZero);
+                       computeDesiredState(kPowerStateZero, true);
+                       requestDomainPower( fDesiredPowerState );
+                       PM_LOG1("%s: tickle desire removed\n", fName);
+               }
+
+               // Invalidate tickle cache so the next tickle will issue a request
+               IOLockLock(fActivityLock);
+               fDeviceWasActive = false;
+               fActivityTicklePowerState = kInvalidTicklePowerState;
+               IOLockUnlock(fActivityLock);
+
+               fIdleTimerMinPowerState = kPowerStateZero;
+       } else if (fAdvisoryTickleUsed) {
+               // Less aggressive mechanism to accelerate idle timer expiration
+               // before system sleep. May not always allow the driver to wake
+               // up from system sleep in the min power state.
+
+               AbsoluteTime    now;
+               uint64_t        nsec;
+               bool            dropTickleDesire = false;
+
+               if (fIdleTimerPeriod && !fIdleTimerIgnored &&
+                   (fIdleTimerMinPowerState == kPowerStateZero) &&
+                   (fDeviceDesire != kPowerStateZero)) {
+                       IOLockLock(fActivityLock);
+
+                       if (!fDeviceWasActive) {
+                               // No tickles since the last idle timer expiration.
+                               // Safe to drop the device desire to zero.
+                               dropTickleDesire = true;
+                       } else {
+                               // Was tickled since the last idle timer expiration,
+                               // but not in the last minute.
+                               clock_get_uptime(&now);
+                               SUB_ABSOLUTETIME(&now, &fDeviceActiveTimestamp);
+                               absolutetime_to_nanoseconds(now, &nsec);
+                               if (nsec >= kNoTickleCancelWindow) {
+                                       dropTickleDesire = true;
+                               }
+                       }
+
+                       if (dropTickleDesire) {
+                               // Force the next tickle to raise power state
+                               fDeviceWasActive = false;
+                               fActivityTicklePowerState = kInvalidTicklePowerState;
+                       }
+
+                       IOLockUnlock(fActivityLock);
+               }
+
+               if (dropTickleDesire) {
+                       // Advisory tickle desire is intentionally untouched since
+                       // it has no effect until system is promoted to full wake.
+
+                       updatePowerClient(gIOPMPowerClientDevice, kPowerStateZero);
+                       computeDesiredState(kPowerStateZero, true);
+                       PM_LOG1("%s: tickle desire dropped\n", fName);
+               }
+       }
+}
+
+//*********************************************************************************
+// [private] ParentChangeTellPriorityClientsPowerDown
 //
-// We enter the highest state until addPowerChild is called.
+// All applications and kernel clients have acknowledged our intention to drop
+// power.  Here we notify "priority" clients that we are lowering power.
 //*********************************************************************************
 
-IOReturn IOService::temporaryPowerClampOn ( void )
+void
+IOService::ParentChangeTellPriorityClientsPowerDown( void )
 {
-    priv->clampOn = true;
-    makeUsable();
-    return IOPMNoErr;
+       fMachineState = kIOPM_ParentChangeNotifyInterestedDriversWillChange;
+       tellChangeDown2(fHeadNotePowerState);
 }
 
-
 //*********************************************************************************
-// makeUsable
-//
-// Some client of our device is asking that we become usable.  Although
-// this has not come from a subclassed device object, treat it exactly
-// as if it had.  In this way, subsequent requests for lower power from
-// a subclassed device object will pre-empt this request.
+// [private] ParentChangeTellCapabilityWillChange
 //
-// We treat this as a subclass object request to switch to the
-// highest power state.
+// All (legacy) applications and kernel clients have acknowledged, extra stage for
+// root domain to notify apps and drivers about the system capability change.
 //*********************************************************************************
 
-IOReturn IOService::makeUsable ( void )
+void
+IOService::ParentChangeTellCapabilityWillChange( void )
 {
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogMakeUsable,0,0);
+       if (!IS_ROOT_DOMAIN) {
+               return ParentChangeNotifyInterestedDriversWillChange();
+       }
 
-    if ( pm_vars->theControllingDriver == NULL ) 
-    {
-        priv->need_to_become_usable = true;
-        return IOPMNoErr;
-    }
-    priv->deviceDesire = pm_vars->theNumberOfPowerStates - 1;
-    computeDesiredState();
-    if ( inPlane(gIOPowerPlane) && (pm_vars->parentsKnowState) ) 
-    {
-        return changeState();
-    }
-    return IOPMNoErr;
+       tellSystemCapabilityChange( kIOPM_ParentChangeNotifyInterestedDriversWillChange );
 }
 
-
 //*********************************************************************************
-// currentCapability
+// [private] ParentChangeNotifyInterestedDriversWillChange
 //
+// All applications and kernel clients have acknowledged our power state change.
+// Here we notify interested drivers pre-change.
 //*********************************************************************************
 
-IOPMPowerFlags IOService::currentCapability ( void )
+void
+IOService::ParentChangeNotifyInterestedDriversWillChange( void )
 {
-    if ( pm_vars->theControllingDriver == NULL ) 
-    {
-        return 0;
-    } else {
-        return   pm_vars->thePowerStates[pm_vars->myCurrentState].capabilityFlags;
-    }
+       notifyAll( kIOPM_ParentChangeSetPowerState );
 }
 
-
 //*********************************************************************************
-// changePowerStateTo
+// [private] ParentChangeSetPowerState
 //
-// For some reason, our power-controlling driver has decided it needs to change
-// power state.  We enqueue the power change so that appropriate parties
-// will be notified, and then we will instruct the driver to make the change.
+// Instruct our controlling driver to program the hardware for the power state
+// change. Wait for async completions.
 //*********************************************************************************
 
-IOReturn IOService::changePowerStateTo ( unsigned long ordinal )
+void
+IOService::ParentChangeSetPowerState( void )
 {
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogChangeStateTo,ordinal,0);
-
-    if ( ordinal >= pm_vars->theNumberOfPowerStates ) 
-    {
-        return IOPMParameterError;
-    }
-    priv->driverDesire = ordinal;
-    computeDesiredState();
-    if ( inPlane(gIOPowerPlane) && (pm_vars->parentsKnowState) ) 
-    {
-        return changeState();
-    }
+       MS_PUSH( kIOPM_ParentChangeWaitForPowerSettle );
+       fMachineState     = kIOPM_DriverThreadCallDone;
+       fDriverCallReason = kDriverCallSetPowerState;
 
-    return IOPMNoErr;
+       if (notifyControllingDriver() == false) {
+               notifyControllingDriverDone();
+       }
 }
 
 //*********************************************************************************
-// changePowerStateToPriv
+// [private] ParentChangeWaitForPowerSettle
 //
-// For some reason, a subclassed device object has decided it needs to change
-// power state.  We enqueue the power change so that appropriate parties
-// will be notified, and then we will instruct the driver to make the change.
+// Our controlling driver has completed the power state change initiated by our
+// parent. Wait for the driver specified settle time to expire.
 //*********************************************************************************
 
-IOReturn IOService::changePowerStateToPriv ( unsigned long ordinal )
+void
+IOService::ParentChangeWaitForPowerSettle( void )
 {
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogChangeStateToPriv,ordinal,0);
+       fMachineState = kIOPM_ParentChangeNotifyInterestedDriversDidChange;
+       startSettleTimer();
+}
 
-    if ( pm_vars->theControllingDriver == NULL) 
-    {
-        return IOPMNotYetInitialized;
-    }
-    if ( ordinal >= pm_vars->theNumberOfPowerStates ) 
-    {
-        return IOPMParameterError;
-    }
-    priv->deviceDesire = ordinal;
-    computeDesiredState();
-    if ( inPlane(gIOPowerPlane) && (pm_vars->parentsKnowState) ) 
-    {
-        return changeState();
-    }
+//*********************************************************************************
+// [private] ParentChangeNotifyInterestedDriversDidChange
+//
+// Power has settled on a power change initiated by our parent. Here we notify
+// all our interested drivers post-change.
+//*********************************************************************************
 
-    return IOPMNoErr;
+void
+IOService::ParentChangeNotifyInterestedDriversDidChange( void )
+{
+       notifyAll( kIOPM_ParentChangeTellCapabilityDidChange );
 }
 
-
 //*********************************************************************************
-// computeDesiredState
+// [private] ParentChangeTellCapabilityDidChange
 //
+// For root domain to notify capability power-change.
 //*********************************************************************************
 
-void IOService::computeDesiredState ( void )
+void
+IOService::ParentChangeTellCapabilityDidChange( void )
 {
-    OSIterator                      *iter;
-    OSObject                        *next;
-    IOPowerConnection               *connection;
-    unsigned long                   newDesiredState = 0;
+       if (!IS_ROOT_DOMAIN) {
+               return ParentChangeAcknowledgePowerChange();
+       }
 
-    // Compute the maximum  of our children's desires, our controlling driver's desire, and the subclass device's desire.
-    if ( !  priv->device_overrides ) 
-    {
-        iter = getChildIterator(gIOPowerPlane);
-
-        if ( iter ) 
-        {
-            while ( (next = iter->getNextObject()) ) 
-            {
-                if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-                {
-                    if ( connection->getDesiredDomainState() > newDesiredState ) 
-                    {
-                        newDesiredState = connection->getDesiredDomainState();
-                    }
-                }
-            }
-            iter->release();
-        }
-        
-        if (  priv->driverDesire > newDesiredState ) 
-        {
-            newDesiredState =  priv->driverDesire;
-        }
-    }
+       tellSystemCapabilityChange( kIOPM_ParentChangeAcknowledgePowerChange );
+}
 
-    if ( priv->deviceDesire > newDesiredState ) 
-    {
-        newDesiredState = priv->deviceDesire;
-    }
+//*********************************************************************************
+// [private] ParentAcknowledgePowerChange
+//
+// Acknowledge our power parent that our power change is done.
+//*********************************************************************************
 
-    priv->ourDesiredPowerState = newDesiredState;
+void
+IOService::ParentChangeAcknowledgePowerChange( void )
+{
+       IORegistryEntry *   nub;
+       IOService *         parent;
+
+       nub = fHeadNoteParentConnection;
+       nub->retain();
+       all_done();
+       parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
+       if (parent) {
+               parent->acknowledgePowerChange((IOService *)nub);
+               parent->release();
+       }
+       nub->release();
 }
 
+// MARK: -
+// MARK: Ack and Settle timers
 
 //*********************************************************************************
-// changeState
+// [private] settleTimerExpired
 //
-// A subclass object, our controlling driver, or a power domain child
-// has asked for a different power state.  Here we compute what new
-// state we should enter and enqueue the change (or start it).
+// Power has settled after our last change.  Notify interested parties that
+// there is a new power state.
 //*********************************************************************************
 
-IOReturn IOService::changeState ( void )
+void
+IOService::settleTimerExpired( void )
 {
-    // if not fully initialized
-    if ( (pm_vars->theControllingDriver == NULL) ||
-                    !(inPlane(gIOPowerPlane)) ||
-                    !(pm_vars->parentsKnowState) ) 
-    {
-        // we can do no more
-        return IOPMNoErr;
-    }
-    
-    return enqueuePowerChange(IOPMWeInitiated,priv->ourDesiredPowerState,0,0,0);
+       fSettleTimeUS = 0;
+       gIOPMWorkQueue->signalWorkAvailable();
 }
 
-
 //*********************************************************************************
-// currentPowerConsumption
+// settle_timer_expired
 //
+// Holds a retain while the settle timer callout is in flight.
 //*********************************************************************************
 
-unsigned long IOService::currentPowerConsumption ( void )
+static void
+settle_timer_expired( thread_call_param_t arg0, thread_call_param_t arg1 )
 {
-    if ( pm_vars->theControllingDriver == NULL ) 
-    {
-        return kIOPMUnknown;
-    }
-    if ( pm_vars->thePowerStates[pm_vars->myCurrentState].capabilityFlags & kIOPMStaticPowerValid ) 
-    {
-        return  pm_vars->thePowerStates[pm_vars->myCurrentState].staticPower;
-    }
-    return kIOPMUnknown;
+       IOService * me = (IOService *) arg0;
+
+       if (gIOPMWorkLoop && gIOPMWorkQueue) {
+               gIOPMWorkLoop->runAction(
+                       OSMemberFunctionCast(IOWorkLoop::Action, me, &IOService::settleTimerExpired),
+                       me);
+       }
+       me->release();
 }
 
 //*********************************************************************************
-// activityTickle
+// [private] startSettleTimer
 //
-// The activity tickle with parameter kIOPMSubclassPolicyis not handled
-// here and should have been intercepted by the subclass.
-// The tickle with parameter kIOPMSuperclassPolicy1 causes the activity
-// flag to be set, and the device state checked.  If the device has been
-// powered down, it is powered up again.
+// Calculate a power-settling delay in microseconds and start a timer.
 //*********************************************************************************
 
-bool IOService::activityTickle ( unsigned long type, unsigned long stateNumber )
-{
-    IOPMrootDomain                      *pmRootDomain;
-    AbsoluteTime                        uptime;
-
-    if ( type == kIOPMSuperclassPolicy1 ) 
-    {
-        if ( pm_vars->theControllingDriver == NULL ) 
-        {
-            return true;
-        }
-        
-        if( priv->activityLock == NULL )
-        {
-            priv->activityLock = IOLockAlloc();
-        }
-        
-        IOTakeLock(priv->activityLock);
-        priv->device_active = true;
+void
+IOService::startSettleTimer( void )
+{
+#if NOT_USEFUL
+       // This function is broken and serves no useful purpose since it never
+       // updates fSettleTimeUS to a non-zero value to stall the state machine,
+       // yet it starts a delay timer. It appears no driver relies on a delay
+       // from settleUpTime and settleDownTime in the power state table.
+
+       AbsoluteTime        deadline;
+       IOPMPowerStateIndex stateIndex;
+       IOPMPowerStateIndex currentOrder, newOrder, i;
+       uint32_t            settleTime = 0;
+       boolean_t           pending;
+
+       PM_ASSERT_IN_GATE();
+
+       currentOrder = StateOrder(fCurrentPowerState);
+       newOrder     = StateOrder(fHeadNotePowerState);
+
+       i = currentOrder;
+
+       // lowering power
+       if (newOrder < currentOrder) {
+               while (i > newOrder) {
+                       stateIndex = fPowerStates[i].stateOrderToIndex;
+                       settleTime += (uint32_t) fPowerStates[stateIndex].settleDownTime;
+                       i--;
+               }
+       }
+
+       // raising power
+       if (newOrder > currentOrder) {
+               while (i < newOrder) {
+                       stateIndex = fPowerStates[i + 1].stateOrderToIndex;
+                       settleTime += (uint32_t) fPowerStates[stateIndex].settleUpTime;
+                       i++;
+               }
+       }
+
+       if (settleTime) {
+               retain();
+               clock_interval_to_deadline(settleTime, kMicrosecondScale, &deadline);
+               pending = thread_call_enter_delayed(fSettleTimer, deadline);
+               if (pending) {
+                       release();
+               }
+       }
+#endif
+}
 
-        clock_get_uptime(&uptime);
-        priv->device_active_timestamp = uptime;
+//*********************************************************************************
+// [private] ackTimerTick
+//
+// The acknowledgement timeout periodic timer has ticked.
+// If we are awaiting acks for a power change notification,
+// we decrement the timer word of each interested driver which hasn't acked.
+// If a timer word becomes zero, we pretend the driver aknowledged.
+// If we are waiting for the controlling driver to change the power
+// state of the hardware, we decrement its timer word, and if it becomes
+// zero, we pretend the driver acknowledged.
+//
+// Returns true if the timer tick made it possible to advance to the next
+// machine state, false otherwise.
+//*********************************************************************************
 
-        if ( pm_vars->myCurrentState >= stateNumber) 
-        {
-            IOUnlock(priv->activityLock);
-            return true;
-        }
-        IOUnlock(priv->activityLock);
-        
-        // Transfer execution to the PM workloop
-        if( (pmRootDomain = getPMRootDomain()) )
-            pmRootDomain->unIdleDevice(this, stateNumber);
+#ifndef __LP64__
+#if MACH_ASSERT
+__dead2
+#endif
+void
+IOService::ack_timer_ticked( void )
+{
+       assert(false);
+}
+#endif /* !__LP64__ */
 
-        return false;
-    }
-    return true;
+bool
+IOService::ackTimerTick( void )
+{
+       IOPMinformee *      nextObject;
+       bool                done = false;
+
+       PM_ASSERT_IN_GATE();
+       switch (fMachineState) {
+       case kIOPM_OurChangeWaitForPowerSettle:
+       case kIOPM_ParentChangeWaitForPowerSettle:
+               // are we waiting for controlling driver to acknowledge?
+               if (fDriverTimer > 0) {
+                       // yes, decrement timer tick
+                       fDriverTimer--;
+                       if (fDriverTimer == 0) {
+                               // controlling driver is tardy
+                               uint64_t nsec = computeTimeDeltaNS(&fDriverCallStartTime);
+                               OUR_PMLog(kPMLogCtrlDriverTardy, 0, 0);
+                               setProperty(kIOPMTardyAckSPSKey, kOSBooleanTrue);
+                               PM_ERROR("%s::setPowerState(%p, %lu -> %lu) timed out after %d ms\n",
+                                   fName, OBFUSCATE(this), fCurrentPowerState, fHeadNotePowerState, NS_TO_MS(nsec));
+
+#if DEBUG || DEVELOPMENT || CONFIG_EMBEDDED
+                               uint32_t panic_allowed = -1;
+                               PE_parse_boot_argn("setpowerstate_panic", &panic_allowed, sizeof(panic_allowed));
+                               if (panic_allowed != 0) {
+                                       // rdar://problem/48743340 - excluding AppleSEPManager from panic
+                                       const char *whitelist = "AppleSEPManager";
+                                       if (strncmp(fName, whitelist, strlen(whitelist))) {
+                                               panic("%s::setPowerState(%p, %lu -> %lu) timed out after %d ms",
+                                                   fName, this, fCurrentPowerState, fHeadNotePowerState, NS_TO_MS(nsec));
+                                       }
+                               } else {
+                                       PM_ERROR("setPowerState panic disabled by setpowerstate_panic boot-arg\n");
+                               }
+#else
+                               if (gIOKitDebug & kIOLogDebugPower) {
+                                       panic("%s::setPowerState(%p, %lu -> %lu) timed out after %d ms",
+                                           fName, this, fCurrentPowerState, fHeadNotePowerState, NS_TO_MS(nsec));
+                               } else {
+                                       // panic for first party kexts
+                                       const void *function_addr = NULL;
+                                       OSKext *kext = NULL;
+                                       function_addr = OSMemberFunctionCast(const void *, fControllingDriver, &IOService::setPowerState);
+                                       kext = OSKext::lookupKextWithAddress((vm_address_t)function_addr);
+                                       if (kext) {
+                                               const char *bundleID = kext->getIdentifierCString();
+                                               const char *apple_prefix = "com.apple";
+                                               const char *kernel_prefix = "__kernel__";
+                                               if (strncmp(bundleID, apple_prefix, strlen(apple_prefix)) == 0 || strncmp(bundleID, kernel_prefix, strlen(kernel_prefix)) == 0) {
+                                                       // first party client
+                                                       panic("%s::setPowerState(%p : %p, %lu -> %lu) timed out after %d ms",
+                                                           fName, this, function_addr, fCurrentPowerState, fHeadNotePowerState, NS_TO_MS(nsec));
+                                               }
+                                               kext->release();
+                                       }
+                                       // Unblock state machine and pretend driver has acked.
+                                       done = true;
+                               }
+#endif
+                               getPMRootDomain()->reset_watchdog_timer(this, 0);
+                       } else {
+                               // still waiting, set timer again
+                               start_ack_timer();
+                       }
+               }
+               break;
+
+       case kIOPM_NotifyChildrenStart:
+               // are we waiting for interested parties to acknowledge?
+               if (fHeadNotePendingAcks != 0) {
+                       // yes, go through the list of interested drivers
+                       nextObject = fInterestedDrivers->firstInList();
+                       // and check each one
+                       while (nextObject != NULL) {
+                               if (nextObject->timer > 0) {
+                                       nextObject->timer--;
+                                       // this one should have acked by now
+                                       if (nextObject->timer == 0) {
+                                               uint64_t nsec = computeTimeDeltaNS(&nextObject->startTime);
+                                               OUR_PMLog(kPMLogIntDriverTardy, 0, 0);
+                                               nextObject->whatObject->setProperty(kIOPMTardyAckPSCKey, kOSBooleanTrue);
+                                               PM_ERROR("%s::powerState%sChangeTo(%p, %s, %lu -> %lu) timed out after %d ms\n",
+                                                   nextObject->whatObject->getName(),
+                                                   (fDriverCallReason == kDriverCallInformPreChange) ? "Will" : "Did",
+                                                   OBFUSCATE(nextObject->whatObject), fName, fCurrentPowerState, fHeadNotePowerState,
+                                                   NS_TO_MS(nsec));
+
+                                               // Pretend driver has acked.
+                                               fHeadNotePendingAcks--;
+                                       }
+                               }
+                               nextObject = fInterestedDrivers->nextInList(nextObject);
+                       }
+
+                       // is that the last?
+                       if (fHeadNotePendingAcks == 0) {
+                               // yes, we can continue
+                               done = true;
+                               getPMRootDomain()->reset_watchdog_timer(this, 0);
+                       } else {
+                               // no, set timer again
+                               start_ack_timer();
+                       }
+               }
+               break;
+
+       // TODO: aggreggate this
+       case kIOPM_OurChangeTellClientsPowerDown:
+       case kIOPM_OurChangeTellUserPMPolicyPowerDown:
+       case kIOPM_OurChangeTellPriorityClientsPowerDown:
+       case kIOPM_OurChangeNotifyInterestedDriversWillChange:
+       case kIOPM_ParentChangeTellPriorityClientsPowerDown:
+       case kIOPM_ParentChangeNotifyInterestedDriversWillChange:
+       case kIOPM_SyncTellClientsPowerDown:
+       case kIOPM_SyncTellPriorityClientsPowerDown:
+       case kIOPM_SyncNotifyWillChange:
+       case kIOPM_TellCapabilityChangeDone:
+               // apps didn't respond in time
+               cleanClientResponses(true);
+               OUR_PMLog(kPMLogClientTardy, 0, 1);
+               // tardy equates to approval
+               done = true;
+               break;
+
+       default:
+               PM_LOG1("%s: unexpected ack timer tick (state = %d)\n",
+                   getName(), fMachineState);
+               break;
+       }
+       return done;
 }
 
 //*********************************************************************************
-// getPMworkloop
-//
-// A child is calling to get a pointer to the Power Management workloop.
-// We got it or get it from one of our parents.
+// [private] start_watchdog_timer
 //*********************************************************************************
-
-IOWorkLoop * IOService::getPMworkloop ( void )
+void
+IOService::start_watchdog_timer( void )
 {
-    IOService                       *nub;
-    IOService                       *parent;
+       int             timeout;
+       uint64_t        deadline;
 
-    if ( ! inPlane(gIOPowerPlane) ) 
-    {
-        return NULL;
-    }
-    // we have no workloop yet
-    if ( pm_vars->PMworkloop == NULL ) 
-    {
-        nub = (IOService *)copyParentEntry(gIOPowerPlane);
-        if ( nub ) 
-        {
-            parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-            nub->release();
-            // ask one of our parents for the workloop
-            if ( parent ) 
-            {
-                pm_vars->PMworkloop = parent->getPMworkloop();
-                parent->release();
-            }
-        }
-    }
-    return  pm_vars->PMworkloop;
+       if (!fWatchdogTimer || (kIOSleepWakeWdogOff & gIOKitDebug)) {
+               return;
+       }
+
+       IOLockLock(fWatchdogLock);
+
+       timeout = getPMRootDomain()->getWatchdogTimeout();
+       clock_interval_to_deadline(timeout, kSecondScale, &deadline);
+       fWatchdogDeadline = deadline;
+       start_watchdog_timer(deadline);
+       IOLockUnlock(fWatchdogLock);
 }
 
+void
+IOService::start_watchdog_timer(uint64_t deadline)
+{
+       IOLockAssert(fWatchdogLock, kIOLockAssertOwned);
+
+       if (!thread_call_isactive(fWatchdogTimer)) {
+               thread_call_enter_delayed(fWatchdogTimer, deadline);
+       }
+}
 
 //*********************************************************************************
-// setIdleTimerPeriod
-//
-// A subclass policy-maker is going to use our standard idleness
-// detection service.  Make a command queue and an idle timer and
-// connect them to the power management workloop.  Finally,
-// start the timer.
+// [private] stop_watchdog_timer
 //*********************************************************************************
 
-IOReturn  IOService::setIdleTimerPeriod ( unsigned long period )
+void
+IOService::stop_watchdog_timer( void )
 {
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMsetIdleTimerPeriod,period, 0);
+       if (!fWatchdogTimer || (kIOSleepWakeWdogOff & gIOKitDebug)) {
+               return;
+       }
 
-    priv->idle_timer_period = period;
+       IOLockLock(fWatchdogLock);
 
-    if ( period > 0 ) 
-    {
-        if ( getPMworkloop() == NULL ) 
-        {
-            return kIOReturnError;
-        }
-        
-               // make the timer event
-        if (  priv->timerEventSrc == NULL ) 
-        {
-            priv->timerEventSrc = IOTimerEventSource::timerEventSource(this,
-                                                    PM_idle_timer_expired);
-            if ((!priv->timerEventSrc) ||
-                    (pm_vars->PMworkloop->addEventSource(priv->timerEventSrc) != kIOReturnSuccess) ) 
-            {
-                return kIOReturnError;
-            }
-        }
+       thread_call_cancel(fWatchdogTimer);
+       fWatchdogDeadline = 0;
 
-        if ( priv->activityLock == NULL ) 
-        {
-            priv->activityLock = IOLockAlloc();
-        }
+       while (fBlockedArray->getCount()) {
+               IOService *obj = OSDynamicCast(IOService, fBlockedArray->getObject(0));
+               if (obj) {
+                       PM_ERROR("WDOG:Object %s unexpected in blocked array\n", obj->fName);
+                       fBlockedArray->removeObject(0);
+               }
+       }
 
-        start_PM_idle_timer();
-    }
-    return IOPMNoErr;
+       IOLockUnlock(fWatchdogLock);
 }
 
-
 //*********************************************************************************
-// start_PM_idle_timer
-//
-// The parameter is a pointer to us.  Use it to call our timeout method.
+// reset_watchdog_timer
 //*********************************************************************************
-void IOService::start_PM_idle_timer ( void )
+
+void
+IOService::reset_watchdog_timer(IOService *blockedObject, int pendingResponseTimeout)
 {
-    AbsoluteTime                        uptime;
-    AbsoluteTime                        delta;
-    UInt64                              delta_ns;
-    UInt64                              delta_secs;
-    UInt64                              delay_secs;
+       unsigned int i;
+       uint64_t    deadline;
+       IOService *obj;
+
+       if (!fWatchdogTimer || (kIOSleepWakeWdogOff & gIOKitDebug)) {
+               return;
+       }
+
+
+       IOLockLock(fWatchdogLock);
+       if (!fWatchdogDeadline) {
+               goto exit;
+       }
+
+       i = fBlockedArray->getNextIndexOfObject(blockedObject, 0);
+       if (pendingResponseTimeout == 0) {
+               blockedObject->fPendingResponseDeadline = 0;
+               if (i == (unsigned int)-1) {
+                       goto exit;
+               }
+               fBlockedArray->removeObject(i);
+       } else {
+               // Set deadline 2secs after the expected response timeout to allow
+               // ack timer to handle the timeout.
+               clock_interval_to_deadline(pendingResponseTimeout + 2, kSecondScale, &deadline);
+
+               if (i != (unsigned int)-1) {
+                       PM_ERROR("WDOG:Object %s is already blocked for responses. Ignoring timeout %d\n",
+                           fName, pendingResponseTimeout);
+                       goto exit;
+               }
+
+               for (i = 0; i < fBlockedArray->getCount(); i++) {
+                       obj = OSDynamicCast(IOService, fBlockedArray->getObject(i));
+                       if (obj && (obj->fPendingResponseDeadline < deadline)) {
+                               blockedObject->fPendingResponseDeadline = deadline;
+                               fBlockedArray->setObject(i, blockedObject);
+                               break;
+                       }
+               }
+               if (i == fBlockedArray->getCount()) {
+                       blockedObject->fPendingResponseDeadline = deadline;
+                       fBlockedArray->setObject(blockedObject);
+               }
+       }
+
+       obj = OSDynamicCast(IOService, fBlockedArray->getObject(0));
+       if (!obj) {
+               int timeout = getPMRootDomain()->getWatchdogTimeout();
+               clock_interval_to_deadline(timeout, kSecondScale, &deadline);
+       } else {
+               deadline = obj->fPendingResponseDeadline;
+       }
+
+       thread_call_cancel(fWatchdogTimer);
+       start_watchdog_timer(deadline);
+
+exit:
+       IOLockUnlock(fWatchdogLock);
+}
 
-    IOLockLock(priv->activityLock);
 
-    clock_get_uptime(&uptime);
+//*********************************************************************************
+// [static] watchdog_timer_expired
+//
+// Inside PM work loop's gate.
+//*********************************************************************************
+
+void
+IOService::watchdog_timer_expired( thread_call_param_t arg0, thread_call_param_t arg1 )
+{
+       IOService * me = (IOService *) arg0;
 
-    // Calculate time difference using funky macro from clock.h.
-    delta = uptime;
-    SUB_ABSOLUTETIME(&delta, &(priv->device_active_timestamp));
 
-    // Figure it in seconds.
-    absolutetime_to_nanoseconds(delta, &delta_ns);
-    delta_secs = delta_ns / NSEC_PER_SEC;
+       gIOPMWatchDogThread = current_thread();
+       getPMRootDomain()->sleepWakeDebugTrig(true);
+       gIOPMWatchDogThread = NULL;
+       thread_call_free(me->fWatchdogTimer);
+       me->fWatchdogTimer = NULL;
 
-    // Be paranoid about delta somehow exceeding timer period.
-    if (delta_secs < priv->idle_timer_period ) 
-    {
-        delay_secs = priv->idle_timer_period - delta_secs;
-    } else {
-        delay_secs = priv->idle_timer_period;
-    }
+       return;
+}
 
-    priv->timerEventSrc->setTimeout(delay_secs, NSEC_PER_SEC);
 
-    IOLockUnlock(priv->activityLock);
-    return;
+IOWorkLoop *
+IOService::getIOPMWorkloop( void )
+{
+       return gIOPMWorkLoop;
 }
 
 
+
 //*********************************************************************************
-// PM_idle_timer_expired
-//
-// The parameter is a pointer to us.  Use it to call our timeout method.
+// [private] start_ack_timer
 //*********************************************************************************
 
-void PM_idle_timer_expired(OSObject * ourSelves, IOTimerEventSource *)
+void
+IOService::start_ack_timer( void )
 {
-    ((IOService *)ourSelves)->PM_idle_timer_expiration();
+       start_ack_timer( ACK_TIMER_PERIOD, kNanosecondScale );
 }
 
+void
+IOService::start_ack_timer( UInt32 interval, UInt32 scale )
+{
+       AbsoluteTime    deadline;
+       boolean_t       pending;
+
+       clock_interval_to_deadline(interval, scale, &deadline);
+
+       retain();
+       pending = thread_call_enter_delayed(fAckTimer, deadline);
+       if (pending) {
+               release();
+       }
+}
 
 //*********************************************************************************
-// PM_idle_timer_expiration
-//
-// The idle timer has expired.  If there has been activity since the last
-// expiration, just restart the timer and return.  If there has not been
-// activity, switch to the next lower power state and restart the timer.
+// [private] stop_ack_timer
 //*********************************************************************************
 
-void IOService::PM_idle_timer_expiration ( void )
+void
+IOService::stop_ack_timer( void )
 {
-    if ( ! initialized ) 
-    {
-        // we're unloading
-        return;
-    }
+       boolean_t   pending;
 
-    if (  priv->idle_timer_period > 0 ) 
-    {
-        IOTakeLock(priv->activityLock);
-        if ( priv->device_active ) 
-        {
-            priv->device_active = false;
-            IOUnlock(priv->activityLock);
-            start_PM_idle_timer();
-            return;
-        }
-        if ( pm_vars->myCurrentState > 0 ) 
-        {
-            IOUnlock(priv->activityLock);
-            changePowerStateToPriv(pm_vars->myCurrentState - 1);
-            start_PM_idle_timer();
-            return;
-        }
-        IOUnlock(priv->activityLock);
-        start_PM_idle_timer();
-    }
+       pending = thread_call_cancel(fAckTimer);
+       if (pending) {
+               release();
+       }
 }
 
-
-// **********************************************************************************
-// command_received
+//*********************************************************************************
+// [static] actionAckTimerExpired
 //
-// We are un-idling a device due to its activity tickle. This routine runs on the
-// PM workloop, and is initiated by IOService::activityTickle.
-// We process all activityTickle state requests on the list.
-// **********************************************************************************
-void IOService::command_received ( void *statePtr , void *, void * , void * )
+// Inside PM work loop's gate.
+//*********************************************************************************
+
+IOReturn
+IOService::actionAckTimerExpired(
+       OSObject * target,
+       void * arg0, void * arg1,
+       void * arg2, void * arg3 )
 {
-    unsigned long                       stateNumber;
+       IOService * me = (IOService *) target;
+       bool        done;
 
-    stateNumber = (unsigned long)statePtr;
+       // done will be true if the timer tick unblocks the machine state,
+       // otherwise no need to signal the work loop.
 
-    // If not initialized, we're unloading
-    if ( ! initialized ) return;                                       
+       done = me->ackTimerTick();
+       if (done && gIOPMWorkQueue) {
+               gIOPMWorkQueue->signalWorkAvailable();
+       }
 
-    if ( (pm_vars->myCurrentState < stateNumber) &&
-            (priv->imminentState < stateNumber) ) 
-    {
-        changePowerStateToPriv(stateNumber);
-    }
+       return kIOReturnSuccess;
 }
 
-
 //*********************************************************************************
-// setAggressiveness
+// ack_timer_expired
 //
-// Pass on the input parameters to all power domain children. All those which are
-// power domains will pass it on to their children, etc.
+// Thread call function. Holds a retain while the callout is in flight.
 //*********************************************************************************
 
-IOReturn IOService::setAggressiveness ( unsigned long type, unsigned long newLevel )
+void
+IOService::ack_timer_expired( thread_call_param_t arg0, thread_call_param_t arg1 )
 {
-    OSIterator                          *iter;
-    OSObject                            *next;
-    IOPowerConnection                   *connection;
-    IOService                           *child;
+       IOService * me = (IOService *) arg0;
 
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogSetAggressiveness,type, newLevel);
+       if (gIOPMWorkLoop) {
+               gIOPMWorkLoop->runAction(&actionAckTimerExpired, me);
+       }
+       me->release();
+}
 
-    if ( type <= kMaxType ) 
-    {
-        pm_vars->current_aggressiveness_values[type] = newLevel;
-        pm_vars->current_aggressiveness_valid[type] = true;
-    }
 
-    iter = getChildIterator(gIOPowerPlane);
+// MARK: -
+// MARK: Client Messaging
 
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                child = ((IOService *)(connection->copyChildEntry(gIOPowerPlane)));
-                if ( child ) 
-                {
-                    child->setAggressiveness(type, newLevel);
-                    child->release();
-                }
-            }
-        }
-        iter->release();
-    }
+//*********************************************************************************
+// [private] tellSystemCapabilityChange
+//*********************************************************************************
 
-    return IOPMNoErr;
+void
+IOService::tellSystemCapabilityChange( uint32_t nextMS )
+{
+       MS_PUSH( nextMS );
+       fMachineState       = kIOPM_TellCapabilityChangeDone;
+       fOutOfBandMessage   = kIOMessageSystemCapabilityChange;
+
+       if (fIsPreChange) {
+               // Notify app first on pre-change.
+               fOutOfBandParameter = kNotifyCapabilityChangeApps;
+       } else {
+               // Notify kernel clients first on post-change.
+               fOutOfBandParameter = kNotifyCapabilityChangePriority;
+       }
+
+       tellClientsWithResponse( fOutOfBandMessage );
 }
 
 //*********************************************************************************
-// getAggressiveness
+// [public] askChangeDown
 //
-// Called by the user client.
+// Ask registered applications and kernel clients if we can change to a lower
+// power state.
+//
+// Subclass can override this to send a different message type.  Parameter is
+// the destination state number.
+//
+// Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-IOReturn IOService::getAggressiveness ( unsigned long type, unsigned long * currentLevel )
+bool
+IOService::askChangeDown( unsigned long stateNum )
 {
-//    if ( type > kMaxType ) 
-//        return kIOReturnBadArgument;
-
-    if ( !pm_vars->current_aggressiveness_valid[type] )
-        return kIOReturnInvalid;
-    *currentLevel = pm_vars->current_aggressiveness_values[type];
-    
-    return kIOReturnSuccess;
+       return tellClientsWithResponse( kIOMessageCanDevicePowerOff );
 }
 
 //*********************************************************************************
-// systemWake
+// [private] tellChangeDown1
 //
-// Pass this to all power domain children. All those which are
-// power domains will pass it on to their children, etc.
+// Notify registered applications and kernel clients that we are definitely
+// dropping power.
+//
+// Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-IOReturn IOService::systemWake ( void )
+bool
+IOService::tellChangeDown1( unsigned long stateNum )
 {
-    OSIterator                          *iter;
-    OSObject                            *next;
-    IOPowerConnection                   *connection;
-    IOService                           *theChild;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogSystemWake,0, 0);
-
-    iter = getChildIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                theChild = (IOService *)connection->copyChildEntry(gIOPowerPlane);
-                if ( theChild ) 
-                {
-                       theChild->systemWake();
-                    theChild->release();
-                }
-            }
-        }
-        iter->release();
-    }
-
-    if ( pm_vars->theControllingDriver != NULL ) 
-    {
-        if ( pm_vars->theControllingDriver->didYouWakeSystem() ) 
-        {
-            makeUsable();
-        }
-    }
-
-    return IOPMNoErr;
+       fOutOfBandParameter = kNotifyApps;
+       return tellChangeDown(stateNum);
 }
 
-
 //*********************************************************************************
-// temperatureCriticalForZone
+// [private] tellChangeDown2
+//
+// Notify priority clients that we are definitely dropping power.
 //
+// Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-IOReturn IOService::temperatureCriticalForZone ( IOService * whichZone )
+bool
+IOService::tellChangeDown2( unsigned long stateNum )
 {
-    IOService                       *theParent;
-    IOService                       *theNub;
-    
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogCriticalTemp,0,0);
-
-    if ( inPlane(gIOPowerPlane) && !(priv->we_are_root) ) 
-    {
-        theNub = (IOService *)copyParentEntry(gIOPowerPlane);
-        if ( theNub ) 
-        {
-            theParent = (IOService *)theNub->copyParentEntry(gIOPowerPlane);
-            theNub->release();
-            if ( theParent ) 
-            {
-                theParent->temperatureCriticalForZone(whichZone);
-                theParent->release();
-            }
-        }
-    }
-    return IOPMNoErr;
+       fOutOfBandParameter = kNotifyPriority;
+       return tellChangeDown(stateNum);
 }
 
-
 //*********************************************************************************
-// powerOverrideOnPriv
+// [public] tellChangeDown
+//
+// Notify registered applications and kernel clients that we are definitely
+// dropping power.
+//
+// Subclass can override this to send a different message type.  Parameter is
+// the destination state number.
 //
+// Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-
-IOReturn IOService::powerOverrideOnPriv ( void )
+bool
+IOService::tellChangeDown( unsigned long stateNum )
 {
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogOverrideOn,0,0);
-
-    // turn on the override
-    priv->device_overrides = true;
-    computeDesiredState();
-    
-    // change state if that changed something
-    return changeState();
+       return tellClientsWithResponse( kIOMessageDeviceWillPowerOff );
 }
 
-
 //*********************************************************************************
-// powerOverrideOffPriv
+// cleanClientResponses
 //
 //*********************************************************************************
-IOReturn IOService::powerOverrideOffPriv ( void )
-{
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogOverrideOff,0,0);
 
-    // turn off the override
-    priv->device_overrides = false;
-    computeDesiredState();
-    if( priv->clampOn)
-    {
-        return makeUsable();
-    } else {
-        // change state if that changed something
-        return changeState();
-    }
+static void
+logAppTimeouts( OSObject * object, void * arg )
+{
+       IOPMInterestContext *   context = (IOPMInterestContext *) arg;
+       OSObject *              flag;
+       unsigned int            clientIndex;
+       int                     pid = 0;
+       char                    name[128];
+
+       if (OSDynamicCast(_IOServiceInterestNotifier, object)) {
+               // Discover the 'counter' value or index assigned to this client
+               // when it was notified, by searching for the array index of the
+               // client in an array holding the cached interested clients.
+
+               clientIndex = context->notifyClients->getNextIndexOfObject(object, 0);
+
+               if ((clientIndex != (unsigned int) -1) &&
+                   (flag = context->responseArray->getObject(clientIndex)) &&
+                   (flag != kOSBooleanTrue)) {
+                       OSNumber *clientID = copyClientIDForNotification(object, context);
+
+                       name[0] = '\0';
+                       if (clientID) {
+                               pid = clientID->unsigned32BitValue();
+                               proc_name(pid, name, sizeof(name));
+                               clientID->release();
+                       }
+
+                       PM_ERROR(context->errorLog, pid, name);
+
+                       // TODO: record message type if possible
+                       IOService::getPMRootDomain()->pmStatsRecordApplicationResponse(
+                               gIOPMStatsResponseTimedOut,
+                               name, 0, (30 * 1000), pid, object);
+               }
+       }
 }
 
+void
+IOService::cleanClientResponses( bool logErrors )
+{
+       if (logErrors && fResponseArray) {
+               switch (fOutOfBandParameter) {
+               case kNotifyApps:
+               case kNotifyCapabilityChangeApps:
+                       if (fNotifyClientArray) {
+                               IOPMInterestContext context;
+
+                               context.responseArray    = fResponseArray;
+                               context.notifyClients    = fNotifyClientArray;
+                               context.serialNumber     = fSerialNumber;
+                               context.messageType      = kIOMessageCopyClientID;
+                               context.notifyType       = kNotifyApps;
+                               context.isPreChange      = fIsPreChange;
+                               context.enableTracing    = false;
+                               context.us               = this;
+                               context.maxTimeRequested = 0;
+                               context.stateNumber      = fHeadNotePowerState;
+                               context.stateFlags       = fHeadNotePowerArrayEntry->capabilityFlags;
+                               context.changeFlags      = fHeadNoteChangeFlags;
+                               context.errorLog         = "PM notification timeout (pid %d, %s)\n";
+
+                               applyToInterested(gIOAppPowerStateInterest, logAppTimeouts, (void *) &context);
+                       }
+                       break;
+
+               default:
+                       // kNotifyPriority, kNotifyCapabilityChangePriority
+                       // TODO: identify the priority client that has not acked
+                       PM_ERROR("PM priority notification timeout\n");
+                       if (gIOKitDebug & kIOLogDebugPower) {
+                               panic("PM priority notification timeout");
+                       }
+                       break;
+               }
+       }
+
+       if (IS_ROOT_DOMAIN) {
+               getPMRootDomain()->reset_watchdog_timer(this, 0);
+       }
+       if (fResponseArray) {
+               fResponseArray->release();
+               fResponseArray = NULL;
+       }
+       if (fNotifyClientArray) {
+               fNotifyClientArray->release();
+               fNotifyClientArray = NULL;
+       }
+}
 
 //*********************************************************************************
-// enqueuePowerChange
+// [protected] tellClientsWithResponse
 //
-// Allocate a new state change notification, initialize it with fields from the
-// caller, and add it to the tail of the list of pending power changes.
+// Notify registered applications and kernel clients that we are definitely
+// dropping power.
 //
-// If it is early enough in the list, and almost all the time it is the only one in
-// the list, start the power change.
+// Return true if we don't have to wait for acknowledgements
+//*********************************************************************************
+
+bool
+IOService::tellClientsWithResponse( int messageType )
+{
+       IOPMInterestContext     context;
+       bool                    isRootDomain = IS_ROOT_DOMAIN;
+       uint32_t                maxTimeOut = kMaxTimeRequested;
+
+       PM_ASSERT_IN_GATE();
+       assert( fResponseArray == NULL );
+       assert( fNotifyClientArray == NULL );
+
+       if (messageType == (int)kIOPMMessageLastCallBeforeSleep) {
+               RD_LOG("tellClientsWithResponse( kIOPMMessageLastCallBeforeSleep, %d )\n",
+                   fOutOfBandParameter);
+       } else {
+               RD_LOG("tellClientsWithResponse( %s, %d )\n",
+                   getIOMessageString(messageType), fOutOfBandParameter);
+       }
+
+       fResponseArray = OSArray::withCapacity( 1 );
+       if (!fResponseArray) {
+               goto exit;
+       }
+
+       fResponseArray->setCapacityIncrement(8);
+       if (++fSerialNumber == 0) {
+               fSerialNumber++;
+       }
+
+       context.responseArray    = fResponseArray;
+       context.notifyClients    = NULL;
+       context.serialNumber     = fSerialNumber;
+       context.messageType      = messageType;
+       context.notifyType       = fOutOfBandParameter;
+       context.skippedInDark    = 0;
+       context.notSkippedInDark = 0;
+       context.isPreChange      = fIsPreChange;
+       context.enableTracing    = false;
+       context.us               = this;
+       context.maxTimeRequested = 0;
+       context.stateNumber      = fHeadNotePowerState;
+       context.stateFlags       = fHeadNotePowerArrayEntry->capabilityFlags;
+       context.changeFlags      = fHeadNoteChangeFlags;
+       context.messageFilter    = (isRootDomain) ?
+           OSMemberFunctionCast(
+               IOPMMessageFilter,
+               this,
+               &IOPMrootDomain::systemMessageFilter) : NULL;
+
+       switch (fOutOfBandParameter) {
+       case kNotifyApps:
+               applyToInterested( gIOAppPowerStateInterest,
+                   pmTellAppWithResponse, (void *) &context );
+
+               if (isRootDomain &&
+                   (fMachineState != kIOPM_OurChangeTellClientsPowerDown) &&
+                   (fMachineState != kIOPM_SyncTellClientsPowerDown) &&
+                   (context.messageType != kIOPMMessageLastCallBeforeSleep)) {
+                       // Notify capability app for tellChangeDown1()
+                       // but not for askChangeDown().
+                       context.notifyType  = kNotifyCapabilityChangeApps;
+                       context.messageType = kIOMessageSystemCapabilityChange;
+                       applyToInterested( gIOAppPowerStateInterest,
+                           pmTellCapabilityAppWithResponse, (void *) &context );
+                       context.notifyType  = fOutOfBandParameter;
+                       context.messageType = messageType;
+               }
+               if (context.messageType == kIOMessageCanSystemSleep) {
+                       maxTimeOut = kCanSleepMaxTimeReq;
+                       if (gCanSleepTimeout) {
+                               maxTimeOut = (gCanSleepTimeout * us_per_s);
+                       }
+               }
+               context.maxTimeRequested = maxTimeOut;
+               context.enableTracing = isRootDomain;
+               applyToInterested( gIOGeneralInterest,
+                   pmTellClientWithResponse, (void *) &context );
+
+               break;
+
+       case kNotifyPriority:
+               context.enableTracing = isRootDomain;
+               applyToInterested( gIOPriorityPowerStateInterest,
+                   pmTellClientWithResponse, (void *) &context );
+
+               if (isRootDomain) {
+                       // Notify capability clients for tellChangeDown2().
+                       context.notifyType  = kNotifyCapabilityChangePriority;
+                       context.messageType = kIOMessageSystemCapabilityChange;
+                       applyToInterested( gIOPriorityPowerStateInterest,
+                           pmTellCapabilityClientWithResponse, (void *) &context );
+               }
+               break;
+
+       case kNotifyCapabilityChangeApps:
+               applyToInterested( gIOAppPowerStateInterest,
+                   pmTellCapabilityAppWithResponse, (void *) &context );
+               if (context.messageType == kIOMessageCanSystemSleep) {
+                       maxTimeOut = kCanSleepMaxTimeReq;
+                       if (gCanSleepTimeout) {
+                               maxTimeOut = (gCanSleepTimeout * us_per_s);
+                       }
+               }
+               context.maxTimeRequested = maxTimeOut;
+               break;
+
+       case kNotifyCapabilityChangePriority:
+               context.enableTracing = isRootDomain;
+               applyToInterested( gIOPriorityPowerStateInterest,
+                   pmTellCapabilityClientWithResponse, (void *) &context );
+               break;
+       }
+       fNotifyClientArray = context.notifyClients;
+
+       if (context.skippedInDark) {
+               IOLog("tellClientsWithResponse(%s, %d) %d of %d skipped in dark\n",
+                   getIOMessageString(messageType), fOutOfBandParameter,
+                   context.skippedInDark, context.skippedInDark + context.notSkippedInDark);
+       }
+
+       // do we have to wait for somebody?
+       if (!checkForDone()) {
+               OUR_PMLog(kPMLogStartAckTimer, context.maxTimeRequested, 0);
+               if (context.enableTracing) {
+                       getPMRootDomain()->traceDetail(context.messageType, 0, context.maxTimeRequested / 1000);
+                       getPMRootDomain()->reset_watchdog_timer(this, context.maxTimeRequested / USEC_PER_SEC + 1);
+               }
+               start_ack_timer( context.maxTimeRequested / 1000, kMillisecondScale );
+               return false;
+       }
+
+exit:
+       // everybody responded
+       if (fResponseArray) {
+               fResponseArray->release();
+               fResponseArray = NULL;
+       }
+       if (fNotifyClientArray) {
+               fNotifyClientArray->release();
+               fNotifyClientArray = NULL;
+       }
+
+       return true;
+}
+
+//*********************************************************************************
+// [static private] pmTellAppWithResponse
 //
-// In rare instances, this change will preempt the previous change in the list.
-// If the previous change is un-actioned in any way (because we are still
-// processing an even earlier power change), and if both the previous change
-// in the list and this change are initiated by us (not the parent), then we
-// needn't perform the previous change, so we collapse the list a little.
+// We send a message to an application, and we expect a response, so we compute a
+// cookie we can identify the response with.
 //*********************************************************************************
 
-IOReturn IOService::enqueuePowerChange ( unsigned long flags,  unsigned long whatStateOrdinal, unsigned long domainState, IOPowerConnection * whichParent, unsigned long singleParentState )
+void
+IOService::pmTellAppWithResponse( OSObject * object, void * arg )
 {
-    long                            newNote;
-    long                            previousNote;
+       IOPMInterestContext *   context = (IOPMInterestContext *) arg;
+       IOServicePM *           pwrMgt = context->us->pwrMgt;
+       uint32_t                msgIndex, msgRef, msgType;
+       OSNumber                *clientID = NULL;
+       proc_t                  proc = NULL;
+       boolean_t               proc_suspended = FALSE;
+       OSObject *              waitForReply = kOSBooleanTrue;
+#if LOG_APP_RESPONSE_TIMES
+       AbsoluteTime            now;
+#endif
+
+       if (!OSDynamicCast(_IOServiceInterestNotifier, object)) {
+               return;
+       }
+
+       if (context->us == getPMRootDomain()) {
+               if ((clientID = copyClientIDForNotification(object, context))) {
+                       uint32_t clientPID = clientID->unsigned32BitValue();
+                       clientID->release();
+                       proc = proc_find(clientPID);
+
+                       if (proc) {
+                               proc_suspended = get_task_pidsuspended((task_t) proc->task);
+                               if (proc_suspended) {
+                                       logClientIDForNotification(object, context, "PMTellAppWithResponse - Suspended");
+#if !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146))
+                               } else if (getPMRootDomain()->isAOTMode() && get_task_suspended((task_t) proc->task)) {
+                                       proc_suspended = true;
+                                       context->skippedInDark++;
+#endif /* !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+                               }
+                               proc_rele(proc);
+                               if (proc_suspended) {
+                                       return;
+                               }
+                       }
+               }
+       }
+
+       if (context->messageFilter &&
+           !context->messageFilter(context->us, object, context, NULL, &waitForReply)) {
+               if (kIOLogDebugPower & gIOKitDebug) {
+                       logClientIDForNotification(object, context, "DROP App");
+               }
+               return;
+       }
+       context->notSkippedInDark++;
+
+       // Create client array (for tracking purposes) only if the service
+       // has app clients. Usually only root domain does.
+       if (NULL == context->notifyClients) {
+               context->notifyClients = OSArray::withCapacity( 32 );
+       }
+
+       msgType  = context->messageType;
+       msgIndex = context->responseArray->getCount();
+       msgRef   = ((context->serialNumber & 0xFFFF) << 16) + (msgIndex & 0xFFFF);
+
+       OUR_PMLog(kPMLogAppNotify, msgType, msgRef);
+       if (kIOLogDebugPower & gIOKitDebug) {
+               logClientIDForNotification(object, context, "MESG App");
+       }
+
+       if (waitForReply == kOSBooleanTrue) {
+               OSNumber * num;
+               clock_get_uptime(&now);
+               num = OSNumber::withNumber(AbsoluteTime_to_scalar(&now), sizeof(uint64_t) * 8);
+               if (num) {
+                       context->responseArray->setObject(msgIndex, num);
+                       num->release();
+               } else {
+                       context->responseArray->setObject(msgIndex, kOSBooleanFalse);
+               }
+       } else {
+               context->responseArray->setObject(msgIndex, kOSBooleanTrue);
+               if (kIOLogDebugPower & gIOKitDebug) {
+                       logClientIDForNotification(object, context, "App response ignored");
+               }
+       }
+
+       if (context->notifyClients) {
+               context->notifyClients->setObject(msgIndex, object);
+       }
+
+       context->us->messageClient(msgType, object, (void *)(uintptr_t) msgRef);
+}
 
-    // Create and initialize the new change note
+//*********************************************************************************
+// [static private] pmTellClientWithResponse
+//
+// We send a message to an in-kernel client, and we expect a response,
+// so we compute a cookie we can identify the response with.
+//*********************************************************************************
 
-    IOLockLock(priv->queue_lock);
-    newNote = priv->changeList->createChangeNote();
-    if ( newNote == -1 ) {
-        // uh-oh, our list is full
-        IOLockUnlock(priv->queue_lock);
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogEnqueueErr,0,0);
-        return IOPMAckImplied;
-    }
+void
+IOService::pmTellClientWithResponse( OSObject * object, void * arg )
+{
+       IOPowerStateChangeNotification  notify;
+       IOPMInterestContext *           context = (IOPMInterestContext *) arg;
+       OSObject *                      replied = kOSBooleanTrue;
+       _IOServiceInterestNotifier *    notifier;
+       uint32_t                        msgIndex, msgRef, msgType;
+       IOReturn                        retCode;
+       AbsoluteTime                    start, end;
+       uint64_t                        nsec;
+
+       if (context->messageFilter &&
+           !context->messageFilter(context->us, object, context, NULL, NULL)) {
+               if ((kIOLogDebugPower & gIOKitDebug) &&
+                   (OSDynamicCast(_IOServiceInterestNotifier, object))) {
+                       _IOServiceInterestNotifier *n = (_IOServiceInterestNotifier *) object;
+                       PM_LOG("%s DROP Client %s, notifier %p, handler %p\n",
+                           context->us->getName(),
+                           getIOMessageString(context->messageType),
+                           OBFUSCATE(object), OBFUSCATE(n->handler));
+               }
+               return;
+       }
+
+       notifier = OSDynamicCast(_IOServiceInterestNotifier, object);
+       msgType  = context->messageType;
+       msgIndex = context->responseArray->getCount();
+       msgRef   = ((context->serialNumber & 0xFFFF) << 16) + (msgIndex & 0xFFFF);
+
+       IOServicePM * pwrMgt = context->us->pwrMgt;
+       if (gIOKitDebug & kIOLogPower) {
+               OUR_PMLog(kPMLogClientNotify, msgRef, msgType);
+               if (OSDynamicCast(IOService, object)) {
+                       const char *who = ((IOService *) object)->getName();
+                       gPlatform->PMLog(who, kPMLogClientNotify, (uintptr_t) object, 0);
+               } else if (notifier) {
+                       OUR_PMLog(kPMLogClientNotify, (uintptr_t) notifier->handler, 0);
+               }
+       }
+       if ((kIOLogDebugPower & gIOKitDebug) && notifier) {
+               PM_LOG("%s MESG Client %s, notifier %p, handler %p\n",
+                   context->us->getName(),
+                   getIOMessageString(msgType),
+                   OBFUSCATE(object), OBFUSCATE(notifier->handler));
+       }
+
+       if (NULL == context->notifyClients) {
+               context->notifyClients = OSArray::withCapacity( 32 );
+       }
+
+       notify.powerRef    = (void *)(uintptr_t) msgRef;
+       notify.returnValue = 0;
+       notify.stateNumber = context->stateNumber;
+       notify.stateFlags  = context->stateFlags;
+
+       if (context->enableTracing && (notifier != NULL)) {
+               getPMRootDomain()->traceDetail(notifier, true);
+       }
+
+       clock_get_uptime(&start);
+       retCode = context->us->messageClient(msgType, object, (void *) &notify, sizeof(notify));
+       clock_get_uptime(&end);
+
+       if (context->enableTracing && (notifier != NULL)) {
+               getPMRootDomain()->traceDetail(notifier, false);
+       }
+
+
+       if (kIOReturnSuccess == retCode) {
+               if (0 == notify.returnValue) {
+                       OUR_PMLog(kPMLogClientAcknowledge, msgRef, (uintptr_t) object);
+                       context->responseArray->setObject(msgIndex, replied);
+               } else {
+                       replied = kOSBooleanFalse;
+                       if (notify.returnValue > context->maxTimeRequested) {
+                               if (notify.returnValue > kPriorityClientMaxWait) {
+                                       context->maxTimeRequested = kPriorityClientMaxWait;
+                                       PM_ERROR("%s: client %p returned %llu for %s\n",
+                                           context->us->getName(),
+                                           notifier ? (void *)  OBFUSCATE(notifier->handler) : OBFUSCATE(object),
+                                           (uint64_t) notify.returnValue,
+                                           getIOMessageString(msgType));
+                               } else {
+                                       context->maxTimeRequested = notify.returnValue;
+                               }
+                       }
+                       //
+                       // Track time taken to ack, by storing the timestamp of
+                       // callback completion
+                       OSNumber * num;
+                       num = OSNumber::withNumber(AbsoluteTime_to_scalar(&end), sizeof(uint64_t) * 8);
+                       if (num) {
+                               context->responseArray->setObject(msgIndex, num);
+                               num->release();
+                       } else {
+                               context->responseArray->setObject(msgIndex, replied);
+                       }
+               }
+
+               if (context->enableTracing) {
+                       SUB_ABSOLUTETIME(&end, &start);
+                       absolutetime_to_nanoseconds(end, &nsec);
+
+                       if ((nsec > LOG_KEXT_RESPONSE_TIMES) || (notify.returnValue != 0)) {
+                               getPMRootDomain()->traceAckDelay(notifier, notify.returnValue / 1000, NS_TO_MS(nsec));
+                       }
+               }
+       } else {
+               // not a client of ours
+               // so we won't be waiting for response
+               OUR_PMLog(kPMLogClientAcknowledge, msgRef, 0);
+               context->responseArray->setObject(msgIndex, replied);
+       }
+       if (context->notifyClients) {
+               context->notifyClients->setObject(msgIndex, object);
+       }
+}
 
-    priv->changeList->changeNote[newNote].newStateNumber = whatStateOrdinal;
-    priv->changeList->changeNote[newNote].outputPowerCharacter = pm_vars->thePowerStates[whatStateOrdinal].outputPowerCharacter;
-    priv->changeList->changeNote[newNote].inputPowerRequirement = pm_vars->thePowerStates[whatStateOrdinal].inputPowerRequirement;
-    priv->changeList->changeNote[newNote].capabilityFlags = pm_vars->thePowerStates[whatStateOrdinal].capabilityFlags;
-    priv->changeList->changeNote[newNote].flags = flags;
-    priv->changeList->changeNote[newNote].parent = NULL;
-    if (flags & IOPMParentInitiated ) 
-    {
-        priv->changeList->changeNote[newNote].domainState = domainState;
-        priv->changeList->changeNote[newNote].parent = whichParent;
-        whichParent->retain();
-        priv->changeList->changeNote[newNote].singleParentState = singleParentState;
-    }
+//*********************************************************************************
+// [static private] pmTellCapabilityAppWithResponse
+//*********************************************************************************
 
-    previousNote = priv->changeList->previousChangeNote(newNote);
+void
+IOService::pmTellCapabilityAppWithResponse( OSObject * object, void * arg )
+{
+       IOPMSystemCapabilityChangeParameters msgArg;
+       IOPMInterestContext *       context = (IOPMInterestContext *) arg;
+       OSObject *                  replied = kOSBooleanTrue;
+       IOServicePM *               pwrMgt = context->us->pwrMgt;
+       uint32_t                    msgIndex, msgRef, msgType;
+#if LOG_APP_RESPONSE_TIMES
+       AbsoluteTime                now;
+#endif
+
+       if (!OSDynamicCast(_IOServiceInterestNotifier, object)) {
+               return;
+       }
+
+       memset(&msgArg, 0, sizeof(msgArg));
+       if (context->messageFilter &&
+           !context->messageFilter(context->us, object, context, &msgArg, &replied)) {
+               return;
+       }
+
+       if (context->us == getPMRootDomain() &&
+#if !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146))
+           getPMRootDomain()->isAOTMode()
+#else /* !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+           false
+#endif /* (defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+           ) {
+               OSNumber                *clientID = NULL;
+               boolean_t               proc_suspended = FALSE;
+               proc_t                proc = NULL;
+               if ((clientID = copyClientIDForNotification(object, context))) {
+                       uint32_t clientPID = clientID->unsigned32BitValue();
+                       clientID->release();
+                       proc = proc_find(clientPID);
+                       if (proc) {
+                               proc_suspended = get_task_pidsuspended((task_t) proc->task);
+                               if (proc_suspended) {
+                                       logClientIDForNotification(object, context, "PMTellCapablityAppWithResponse - Suspended");
+                               } else if (get_task_suspended((task_t) proc->task)) {
+                                       proc_suspended = true;
+                                       context->skippedInDark++;
+                               }
+                               proc_rele(proc);
+                               if (proc_suspended) {
+                                       return;
+                               }
+                       }
+               }
+       }
+       context->notSkippedInDark++;
+
+       // Create client array (for tracking purposes) only if the service
+       // has app clients. Usually only root domain does.
+       if (NULL == context->notifyClients) {
+               context->notifyClients = OSArray::withCapacity( 32 );
+       }
+
+       msgType  = context->messageType;
+       msgIndex = context->responseArray->getCount();
+       msgRef   = ((context->serialNumber & 0xFFFF) << 16) + (msgIndex & 0xFFFF);
+
+       OUR_PMLog(kPMLogAppNotify, msgType, msgRef);
+       if (kIOLogDebugPower & gIOKitDebug) {
+               // Log client pid/name and client array index.
+               OSNumber * clientID = NULL;
+               OSString * clientIDString = NULL;;
+               context->us->messageClient(kIOMessageCopyClientID, object, &clientID);
+               if (clientID) {
+                       clientIDString = IOCopyLogNameForPID(clientID->unsigned32BitValue());
+               }
+
+               PM_LOG("%s MESG App(%u) %s, wait %u, %s\n",
+                   context->us->getName(),
+                   msgIndex, getIOMessageString(msgType),
+                   (replied != kOSBooleanTrue),
+                   clientIDString ? clientIDString->getCStringNoCopy() : "");
+               if (clientID) {
+                       clientID->release();
+               }
+               if (clientIDString) {
+                       clientIDString->release();
+               }
+       }
+
+       msgArg.notifyRef = msgRef;
+       msgArg.maxWaitForReply = 0;
+
+       if (replied == kOSBooleanTrue) {
+               msgArg.notifyRef = 0;
+               context->responseArray->setObject(msgIndex, kOSBooleanTrue);
+               if (context->notifyClients) {
+                       context->notifyClients->setObject(msgIndex, kOSBooleanTrue);
+               }
+       } else {
+               OSNumber * num;
+               clock_get_uptime(&now);
+               num = OSNumber::withNumber(AbsoluteTime_to_scalar(&now), sizeof(uint64_t) * 8);
+               if (num) {
+                       context->responseArray->setObject(msgIndex, num);
+                       num->release();
+               } else {
+                       context->responseArray->setObject(msgIndex, kOSBooleanFalse);
+               }
+
+               if (context->notifyClients) {
+                       context->notifyClients->setObject(msgIndex, object);
+               }
+       }
+
+       context->us->messageClient(msgType, object, (void *) &msgArg, sizeof(msgArg));
+}
 
-    if ( previousNote == -1 ) 
-    {
+//*********************************************************************************
+// [static private] pmTellCapabilityClientWithResponse
+//*********************************************************************************
 
-        // Queue is empty, we can start this change.
+void
+IOService::pmTellCapabilityClientWithResponse(
+       OSObject * object, void * arg )
+{
+       IOPMSystemCapabilityChangeParameters msgArg;
+       IOPMInterestContext *           context = (IOPMInterestContext *) arg;
+       OSObject *                      replied = kOSBooleanTrue;
+       _IOServiceInterestNotifier *    notifier;
+       uint32_t                        msgIndex, msgRef, msgType;
+       IOReturn                        retCode;
+       AbsoluteTime                    start, end;
+       uint64_t                        nsec;
+
+       memset(&msgArg, 0, sizeof(msgArg));
+       if (context->messageFilter &&
+           !context->messageFilter(context->us, object, context, &msgArg, NULL)) {
+               if ((kIOLogDebugPower & gIOKitDebug) &&
+                   (OSDynamicCast(_IOServiceInterestNotifier, object))) {
+                       _IOServiceInterestNotifier *n = (_IOServiceInterestNotifier *) object;
+                       PM_LOG("%s DROP Client %s, notifier %p, handler %p\n",
+                           context->us->getName(),
+                           getIOMessageString(context->messageType),
+                           OBFUSCATE(object), OBFUSCATE(n->handler));
+               }
+               return;
+       }
+
+       if (NULL == context->notifyClients) {
+               context->notifyClients = OSArray::withCapacity( 32 );
+       }
+       notifier = OSDynamicCast(_IOServiceInterestNotifier, object);
+       msgType  = context->messageType;
+       msgIndex = context->responseArray->getCount();
+       msgRef   = ((context->serialNumber & 0xFFFF) << 16) + (msgIndex & 0xFFFF);
+
+       IOServicePM * pwrMgt = context->us->pwrMgt;
+       if (gIOKitDebug & kIOLogPower) {
+               OUR_PMLog(kPMLogClientNotify, msgRef, msgType);
+               if (OSDynamicCast(IOService, object)) {
+                       const char *who = ((IOService *) object)->getName();
+                       gPlatform->PMLog(who, kPMLogClientNotify, (uintptr_t) object, 0);
+               } else if (notifier) {
+                       OUR_PMLog(kPMLogClientNotify, (uintptr_t) notifier->handler, 0);
+               }
+       }
+       if ((kIOLogDebugPower & gIOKitDebug) && notifier) {
+               PM_LOG("%s MESG Client %s, notifier %p, handler %p\n",
+                   context->us->getName(),
+                   getIOMessageString(msgType),
+                   OBFUSCATE(object), OBFUSCATE(notifier->handler));
+       }
+
+       msgArg.notifyRef = msgRef;
+       msgArg.maxWaitForReply = 0;
+
+       if (context->enableTracing && (notifier != NULL)) {
+               getPMRootDomain()->traceDetail(notifier, true);
+       }
+
+       clock_get_uptime(&start);
+       retCode = context->us->messageClient(
+               msgType, object, (void *) &msgArg, sizeof(msgArg));
+       clock_get_uptime(&end);
+       if (context->enableTracing && (notifier != NULL)) {
+               getPMRootDomain()->traceDetail(notifier, false);
+       }
+
+       if (kIOReturnSuccess == retCode) {
+               if (0 == msgArg.maxWaitForReply) {
+                       // client doesn't want time to respond
+                       OUR_PMLog(kPMLogClientAcknowledge, msgRef, (uintptr_t) object);
+                       context->responseArray->setObject(msgIndex, replied);
+               } else {
+                       replied = kOSBooleanFalse;
+                       if (msgArg.maxWaitForReply > context->maxTimeRequested) {
+                               if (msgArg.maxWaitForReply > kCapabilityClientMaxWait) {
+                                       context->maxTimeRequested = kCapabilityClientMaxWait;
+                                       PM_ERROR("%s: client %p returned %u for %s\n",
+                                           context->us->getName(),
+                                           notifier ? (void *) OBFUSCATE(notifier->handler) : OBFUSCATE(object),
+                                           msgArg.maxWaitForReply,
+                                           getIOMessageString(msgType));
+                               } else {
+                                       context->maxTimeRequested = msgArg.maxWaitForReply;
+                               }
+                       }
+
+                       // Track time taken to ack, by storing the timestamp of
+                       // callback completion
+                       OSNumber * num;
+                       num = OSNumber::withNumber(AbsoluteTime_to_scalar(&end), sizeof(uint64_t) * 8);
+                       if (num) {
+                               context->responseArray->setObject(msgIndex, num);
+                               num->release();
+                       } else {
+                               context->responseArray->setObject(msgIndex, replied);
+                       }
+               }
+
+               if (context->enableTracing) {
+                       SUB_ABSOLUTETIME(&end, &start);
+                       absolutetime_to_nanoseconds(end, &nsec);
+
+                       if ((nsec > LOG_KEXT_RESPONSE_TIMES) || (msgArg.maxWaitForReply != 0)) {
+                               getPMRootDomain()->traceAckDelay(notifier, msgArg.maxWaitForReply / 1000, NS_TO_MS(nsec));
+                       }
+               }
+       } else {
+               // not a client of ours
+               // so we won't be waiting for response
+               OUR_PMLog(kPMLogClientAcknowledge, msgRef, 0);
+               context->responseArray->setObject(msgIndex, replied);
+       }
+       if (context->notifyClients) {
+               context->notifyClients->setObject(msgIndex, object);
+       }
+}
 
-        if (flags & IOPMWeInitiated ) 
-        {
-            IOLockUnlock(priv->queue_lock);
-            start_our_change(newNote);
-            return 0;
-        } else {
-            IOLockUnlock(priv->queue_lock);
-            return start_parent_change(newNote);
-        }
-    }
-
-    // The queue is not empty.  Try to collapse this new change and the previous one in queue into one change.
-    // This is possible only if both changes are initiated by us, and neither has been started yet.
-    // Do this more than once if possible.
-
-    // (A change is started iff it is at the head of the queue)
-
-    while ( (previousNote != priv->head_note) &&  (previousNote != -1) &&
-            (priv->changeList->changeNote[newNote].flags &  priv->changeList->changeNote[previousNote].flags &  IOPMWeInitiated)  ) 
-    {
-        priv->changeList->changeNote[previousNote].outputPowerCharacter = priv->changeList->changeNote[newNote].outputPowerCharacter;
-        priv->changeList->changeNote[previousNote].inputPowerRequirement = priv->changeList->changeNote[newNote].inputPowerRequirement;
-        priv->changeList->changeNote[previousNote].capabilityFlags =priv-> changeList->changeNote[newNote].capabilityFlags;
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogCollapseQueue,priv->changeList->changeNote[newNote].newStateNumber,
-                                                                    priv->changeList->changeNote[previousNote].newStateNumber);
-        priv->changeList->changeNote[previousNote].newStateNumber = priv->changeList->changeNote[newNote].newStateNumber;
-        priv->changeList->releaseTailChangeNote();
-        newNote = previousNote;
-        previousNote = priv->changeList->previousChangeNote(newNote);
-    }
-    IOLockUnlock(priv->queue_lock);
-    // in any case, we can't start yet
-    return IOPMWillAckLater;
-}
-
-//*********************************************************************************
-// notifyAll
-//
-// Notify all interested parties either that a change is impending or that the
-// previously-notified change is done and power has settled.
-// The parameter identifies whether this is the
-// pre-change notification or the post-change notification.
-//
-//*********************************************************************************
-
-IOReturn IOService::notifyAll ( bool is_prechange )
-{
-    IOPMinformee *             nextObject;
-    OSIterator *                       iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-
-    // To prevent acknowledgePowerChange from finishing the change note and removing it from the queue if
-    // some driver calls it, we inflate the number of pending acks so it cannot become zero.  We'll fix it later.
-
-    priv->head_note_pendingAcks =1;
-
-    // OK, we will go through the lists of interested drivers and power domain children
-    // and notify each one of this change.
-
-    nextObject =  priv->interestedDrivers->firstInList();
-    while (  nextObject != NULL ) {
-        priv->head_note_pendingAcks +=1;
-        if (! inform(nextObject, is_prechange) ) 
-        {
-        }
-        nextObject  =  priv->interestedDrivers->nextInList(nextObject);
-    }
-
-    if (! acquire_lock() ) {
-        return IOPMNoErr;
-    }
-    // did they all ack?
-    if ( priv->head_note_pendingAcks > 1 ) {
-        // no
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,0,0);
-        start_ack_timer();
-    }
-    // either way
-    IOUnlock(priv->our_lock);
-
-    // notify children
-    iter = getChildIterator(gIOPowerPlane);
-    // summing their power consumption
-    pm_vars->thePowerStates[priv->head_note_state].staticPower = 0;
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                priv->head_note_pendingAcks +=1;
-                notifyChild(connection, is_prechange);
-            }
-        }
-        iter->release();
-    }
-
-    if (! acquire_lock() ) {
-        return IOPMNoErr;
-    }
-    // now make this real
-    priv->head_note_pendingAcks -= 1;
-    // is it all acked?
-    if (priv->head_note_pendingAcks == 0 ) {
-        // yes, all acked
-        IOUnlock(priv->our_lock);
-        // return ack to parent
-        return IOPMAckImplied;
-    }
-
-    // not all acked
-    IOUnlock(priv->our_lock);
-    return IOPMWillAckLater;
-}
-
-
-//*********************************************************************************
-// notifyChild
+//*********************************************************************************
+// [public] tellNoChangeDown
 //
-// Notify a power domain child of an upcoming power change.
+// Notify registered applications and kernel clients that we are not
+// dropping power.
 //
-// If the object acknowledges the current change, we return TRUE.
+// Subclass can override this to send a different message type.  Parameter is
+// the aborted destination state number.
 //*********************************************************************************
 
-bool IOService::notifyChild ( IOPowerConnection * theNub, bool is_prechange )
-{
-    IOReturn                            k = IOPMAckImplied;
-    unsigned long                       childPower;
-    IOService                           *theChild = (IOService *)(theNub->copyChildEntry(gIOPowerPlane));
-
-    theNub->setAwaitingAck(true);                                      // in case they don't ack
-    
-    if ( ! theChild ) 
-    {
-        return true;
-    }
-    
-    if ( is_prechange ) 
-    {
-        k = theChild->powerDomainWillChangeTo(priv->head_note_outputFlags,theNub);
-    } else {
-        k = theChild->powerDomainDidChangeTo(priv->head_note_outputFlags,theNub);
-    }
-    
-    // did the return code ack?
-    if ( k == IOPMAckImplied ) 
-    {
-        // yes
-        priv->head_note_pendingAcks -=1;
-        theNub->setAwaitingAck(false);
-        childPower = theChild->currentPowerConsumption();
-        if ( childPower == kIOPMUnknown ) 
-        {
-            pm_vars->thePowerStates[priv->head_note_state].staticPower = kIOPMUnknown;
-        } else {
-            if ( pm_vars->thePowerStates[priv->head_note_state].staticPower != kIOPMUnknown ) 
-            {
-                pm_vars->thePowerStates[priv->head_note_state].staticPower += childPower;
-            }
-        }
-        theChild->release();
-        return true;
-    }
-    theChild->release();
-    return false;
-}
-
-
-//*********************************************************************************
-// inform
-//
-// Notify an interested driver of an upcoming power change.
+void
+IOService::tellNoChangeDown( unsigned long )
+{
+       return tellClients( kIOMessageDeviceWillNotPowerOff );
+}
+
+//*********************************************************************************
+// [public] tellChangeUp
 //
-// If the object acknowledges the current change, we return TRUE.
+// Notify registered applications and kernel clients that we are raising power.
+//
+// Subclass can override this to send a different message type.  Parameter is
+// the aborted destination state number.
 //*********************************************************************************
 
-bool IOService::inform ( IOPMinformee * nextObject, bool is_prechange )
+void
+IOService::tellChangeUp( unsigned long )
 {
-    IOReturn                            k = IOPMAckImplied;
-
-    // initialize this
-    nextObject->timer = -1;
-    
-    if ( is_prechange ) 
-    {
-        pm_vars->thePlatform->PMLog (pm_vars->ourName,PMlogInformDriverPreChange,
-                                    (unsigned long)priv->head_note_capabilityFlags,(unsigned long)priv->head_note_state);
-        k = nextObject->whatObject->powerStateWillChangeTo( priv->head_note_capabilityFlags,priv->head_note_state,this);
-    } else {
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogInformDriverPostChange,
-                                    (unsigned long)priv->head_note_capabilityFlags,(unsigned long)priv->head_note_state);
-        k = nextObject->whatObject->powerStateDidChangeTo(priv->head_note_capabilityFlags,priv->head_note_state,this);
-    }
-    
-    // did it ack behind our back?
-    if ( nextObject->timer == 0 ) 
-    {
-        // yes
-        return true;
-    }
-    
-    // no, did the return code ack?
-    if ( k ==IOPMAckImplied ) 
-    {
-        // yes
-        nextObject->timer = 0;
-        priv->head_note_pendingAcks -= 1;
-        return true;
-    }
-    if ( k<0 ) 
-    {
-        // somebody goofed
-        nextObject->timer = 0;
-        priv-> head_note_pendingAcks -= 1;
-        return true;
-    }
-    
-    // no, it's a timer
-    nextObject->timer = (k / (ACK_TIMER_PERIOD / ns_per_us)) + 1;
-
-    return false;
+       return tellClients( kIOMessageDeviceHasPoweredOn );
 }
 
-
 //*********************************************************************************
-// OurChangeTellClientsPowerDown
+// [protected] tellClients
 //
-// All registered applications and kernel clients have positively acknowledged our
-// intention of lowering power.  Here we notify them all that we will definitely
-// lower the power.  If we don't have to wait for any of them to acknowledge, we
-// carry on by notifying interested drivers.  Otherwise, we do wait.
+// Notify registered applications and kernel clients of something.
 //*********************************************************************************
 
-void IOService::OurChangeTellClientsPowerDown ( void )
+void
+IOService::tellClients( int messageType )
 {
-    // next state
-    priv->machine_state = kIOPM_OurChangeTellPriorityClientsPowerDown;
-    
-    // are we waiting for responses?
-    if ( tellChangeDown1(priv->head_note_state) ) 
-    {
-        // no, notify priority clients
-        OurChangeTellPriorityClientsPowerDown();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // allowCancelCommon() or ack timeout    
+       IOPMInterestContext     context;
+
+       RD_LOG("tellClients( %s )\n", getIOMessageString(messageType));
+
+       memset(&context, 0, sizeof(context));
+       context.messageType   = messageType;
+       context.isPreChange   = fIsPreChange;
+       context.us            = this;
+       context.stateNumber   = fHeadNotePowerState;
+       context.stateFlags    = fHeadNotePowerArrayEntry->capabilityFlags;
+       context.changeFlags   = fHeadNoteChangeFlags;
+       context.enableTracing = IS_ROOT_DOMAIN;
+       context.messageFilter = (IS_ROOT_DOMAIN) ?
+           OSMemberFunctionCast(
+               IOPMMessageFilter,
+               this,
+               &IOPMrootDomain::systemMessageFilter) : NULL;
+
+       context.notifyType    = kNotifyPriority;
+       applyToInterested( gIOPriorityPowerStateInterest,
+           tellKernelClientApplier, (void *) &context );
+
+       context.notifyType    = kNotifyApps;
+       applyToInterested( gIOAppPowerStateInterest,
+           tellAppClientApplier, (void *) &context );
+
+       applyToInterested( gIOGeneralInterest,
+           tellKernelClientApplier, (void *) &context );
 }
 
-
 //*********************************************************************************
-// OurChangeTellPriorityClientsPowerDown
+// [private] tellKernelClientApplier
 //
-// All registered applications and kernel clients have positively acknowledged our
-// intention of lowering power.  Here we notify "priority" clients that we are
-// lowering power.  If we don't have to wait for any of them to acknowledge, we
-// carry on by notifying interested drivers.  Otherwise, we do wait.
+// Message a kernel client.
 //*********************************************************************************
 
-void IOService::OurChangeTellPriorityClientsPowerDown ( void )
+static void
+tellKernelClientApplier( OSObject * object, void * arg )
+{
+       IOPowerStateChangeNotification  notify;
+       IOPMInterestContext *           context = (IOPMInterestContext *) arg;
+
+       if (context->messageFilter &&
+           !context->messageFilter(context->us, object, context, NULL, NULL)) {
+               if ((kIOLogDebugPower & gIOKitDebug) &&
+                   (OSDynamicCast(_IOServiceInterestNotifier, object))) {
+                       _IOServiceInterestNotifier *n = (_IOServiceInterestNotifier *) object;
+                       PM_LOG("%s DROP Client %s, notifier %p, handler %p\n",
+                           context->us->getName(),
+                           IOService::getIOMessageString(context->messageType),
+                           OBFUSCATE(object), OBFUSCATE(n->handler));
+               }
+               return;
+       }
+
+       notify.powerRef     = (void *) NULL;
+       notify.returnValue  = 0;
+       notify.stateNumber  = context->stateNumber;
+       notify.stateFlags   = context->stateFlags;
+
+       if (context->enableTracing && object) {
+               IOService::getPMRootDomain()->traceDetail(object, true);
+       }
+       context->us->messageClient(context->messageType, object, &notify, sizeof(notify));
+       if (context->enableTracing && object) {
+               IOService::getPMRootDomain()->traceDetail(object, false);
+       }
+
+
+
+       if ((kIOLogDebugPower & gIOKitDebug) &&
+           (OSDynamicCast(_IOServiceInterestNotifier, object))) {
+               _IOServiceInterestNotifier *n = (_IOServiceInterestNotifier *) object;
+               PM_LOG("%s MESG Client %s, notifier %p, handler %p\n",
+                   context->us->getName(),
+                   IOService::getIOMessageString(context->messageType),
+                   OBFUSCATE(object), OBFUSCATE(n->handler));
+       }
+}
+
+static OSNumber *
+copyClientIDForNotification(
+       OSObject *object,
+       IOPMInterestContext *context)
+{
+       OSNumber *clientID = NULL;
+       context->us->messageClient(kIOMessageCopyClientID, object, &clientID);
+       return clientID;
+}
+
+static void
+logClientIDForNotification(
+       OSObject *object,
+       IOPMInterestContext *context,
+       const char *logString)
 {
-    // next state
-    priv->machine_state = kIOPM_OurChangeNotifyInterestedDriversWillChange;
-    // are we waiting for responses?
-    if ( tellChangeDown2(priv->head_note_state) ) 
-    {
-        // no, notify interested drivers
-        return OurChangeNotifyInterestedDriversWillChange();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // allowCancelCommon() or ack timeout    
+       OSString *logClientID = NULL;
+       OSNumber *clientID = copyClientIDForNotification(object, context);
+
+       if (logString) {
+               if (clientID) {
+                       logClientID = IOCopyLogNameForPID(clientID->unsigned32BitValue());
+               }
+
+               PM_LOG("%s %s %s, %s\n",
+                   context->us->getName(), logString,
+                   IOService::getIOMessageString(context->messageType),
+                   logClientID ? logClientID->getCStringNoCopy() : "");
+
+               if (logClientID) {
+                       logClientID->release();
+               }
+       }
+
+       if (clientID) {
+               clientID->release();
+       }
+
+       return;
 }
 
+static void
+tellAppClientApplier( OSObject * object, void * arg )
+{
+       IOPMInterestContext * context = (IOPMInterestContext *) arg;
+       OSNumber            * clientID = NULL;
+       proc_t                proc = NULL;
+       boolean_t             proc_suspended = FALSE;
+
+       if (context->us == IOService::getPMRootDomain()) {
+               if ((clientID = copyClientIDForNotification(object, context))) {
+                       uint32_t clientPID = clientID->unsigned32BitValue();
+                       clientID->release();
+                       proc = proc_find(clientPID);
+
+                       if (proc) {
+                               proc_suspended = get_task_pidsuspended((task_t) proc->task);
+                               if (proc_suspended) {
+                                       logClientIDForNotification(object, context, "tellAppClientApplier - Suspended");
+#if !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146))
+                               } else if (IOService::getPMRootDomain()->isAOTMode() && get_task_suspended((task_t) proc->task)) {
+                                       proc_suspended = true;
+                                       context->skippedInDark++;
+#endif /* !(defined(RC_HIDE_N144) || defined(RC_HIDE_N146)) */
+                               }
+                               proc_rele(proc);
+                               if (proc_suspended) {
+                                       return;
+                               }
+                       }
+               }
+       }
+
+       if (context->messageFilter &&
+           !context->messageFilter(context->us, object, context, NULL, NULL)) {
+               if (kIOLogDebugPower & gIOKitDebug) {
+                       logClientIDForNotification(object, context, "DROP App");
+               }
+               return;
+       }
+       context->notSkippedInDark++;
+
+       if (kIOLogDebugPower & gIOKitDebug) {
+               logClientIDForNotification(object, context, "MESG App");
+       }
+
+       context->us->messageClient(context->messageType, object, NULL);
+}
 
 //*********************************************************************************
-// OurChangeNotifyInterestedDriversWillChange
-//
-// All registered applications and kernel clients have acknowledged our notification
-// that we are lowering power.  Here we notify interested drivers.  If we don't have
-// to wait for any of them to acknowledge, we instruct our power driver to make the change.
-// Otherwise, we do wait.
+// [private] checkForDone
 //*********************************************************************************
 
-void IOService::OurChangeNotifyInterestedDriversWillChange ( void )
+bool
+IOService::checkForDone( void )
 {
-    // no, in case they don't all ack
-    priv->machine_state = kIOPM_OurChangeSetPowerState;
-    if ( notifyAll(true) == IOPMAckImplied ) 
-    {
-        // not waiting for responses
-        OurChangeSetPowerState();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout
+       int         i = 0;
+       OSObject *  theFlag;
+
+       if (fResponseArray == NULL) {
+               return true;
+       }
+
+       for (i = 0;; i++) {
+               theFlag = fResponseArray->getObject(i);
+
+               if (NULL == theFlag) {
+                       break;
+               }
+
+               if (kOSBooleanTrue != theFlag) {
+                       return false;
+               }
+       }
+       return true;
 }
 
+//*********************************************************************************
+// [public] responseValid
+//*********************************************************************************
+
+bool
+IOService::responseValid( uint32_t refcon, int pid )
+{
+       UInt16          serialComponent;
+       UInt16          ordinalComponent;
+       OSObject *      theFlag;
+       OSObject        *object = NULL;
+
+       serialComponent  = (refcon >> 16) & 0xFFFF;
+       ordinalComponent = (refcon & 0xFFFF);
+
+       if (serialComponent != fSerialNumber) {
+               return false;
+       }
+
+       if (fResponseArray == NULL) {
+               return false;
+       }
+
+       theFlag = fResponseArray->getObject(ordinalComponent);
+
+       if (theFlag == NULL) {
+               return false;
+       }
+
+       if (fNotifyClientArray) {
+               object = fNotifyClientArray->getObject(ordinalComponent);
+       }
+
+       OSNumber * num;
+       if ((num = OSDynamicCast(OSNumber, theFlag))) {
+               AbsoluteTime    now;
+               AbsoluteTime    start;
+               uint64_t        nsec;
+               char            name[128];
+
+               clock_get_uptime(&now);
+               AbsoluteTime_to_scalar(&start) = num->unsigned64BitValue();
+               SUB_ABSOLUTETIME(&now, &start);
+               absolutetime_to_nanoseconds(now, &nsec);
+
+               if (pid != 0) {
+                       name[0] = '\0';
+                       proc_name(pid, name, sizeof(name));
+
+                       if (nsec > LOG_APP_RESPONSE_TIMES) {
+                               IOLog("PM response took %d ms (%d, %s)\n", NS_TO_MS(nsec),
+                                   pid, name);
+                       }
+
+
+                       if (nsec > LOG_APP_RESPONSE_MSG_TRACER) {
+                               // TODO: populate the messageType argument
+                               getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                       gIOPMStatsResponseSlow,
+                                       name, 0, NS_TO_MS(nsec), pid, object);
+                       } else {
+                               getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                       gIOPMStatsResponsePrompt,
+                                       name, 0, NS_TO_MS(nsec), pid, object);
+                       }
+               } else {
+                       getPMRootDomain()->traceAckDelay(object, 0, NS_TO_MS(nsec));
+               }
+
+               if (kIOLogDebugPower & gIOKitDebug) {
+                       PM_LOG("Ack(%u) %u ms\n",
+                           (uint32_t) ordinalComponent,
+                           NS_TO_MS(nsec));
+               }
+               theFlag = kOSBooleanFalse;
+       } else if (object) {
+               getPMRootDomain()->pmStatsRecordApplicationResponse(
+                       gIOPMStatsResponsePrompt,
+                       NULL, 0, 0, pid, object);
+       }
+
+       if (kOSBooleanFalse == theFlag) {
+               fResponseArray->replaceObject(ordinalComponent, kOSBooleanTrue);
+       }
+
+       return true;
+}
 
 //*********************************************************************************
-// OurChangeSetPowerState
+// [public] allowPowerChange
 //
-// All interested drivers have acknowledged our pre-change notification of a power
-// change we initiated.  Here we instruct our controlling driver to make
-// the change to the hardware.  If it does so, we continue processing
-// (waiting for settle and notifying interested parties post-change.)
-// If it doesn't, we have to wait for it to acknowledge and then continue.
+// Our power state is about to lower, and we have notified applications
+// and kernel clients, and one of them has acknowledged.  If this is the last to do
+// so, and all acknowledgements are positive, we continue with the power change.
 //*********************************************************************************
 
-void IOService::OurChangeSetPowerState ( void )
+IOReturn
+IOService::allowPowerChange( unsigned long refcon )
 {
-    priv->machine_state = kIOPM_OurChangeWaitForPowerSettle;
+       IOPMRequest * request;
+
+       if (!initialized) {
+               // we're unloading
+               return kIOReturnSuccess;
+       }
+
+       request = acquirePMRequest( this, kIOPMRequestTypeAllowPowerChange );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       request->fArg0 = (void *)            refcon;
+       request->fArg1 = (void *)(uintptr_t) proc_selfpid();
+       request->fArg2 = (void *)            NULL;
+       submitPMRequest( request );
 
-    if ( instruct_driver(priv->head_note_state) == IOPMAckImplied ) 
-    {
-        // it's done, carry on
-        OurChangeWaitForPowerSettle();
-    } else {
-        // it's not, wait for it
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,0,0);
-        start_ack_timer();
-        // execution will resume via ack_timer_ticked()
-    }
+       return kIOReturnSuccess;
 }
 
+#ifndef __LP64__
+IOReturn
+IOService::serializedAllowPowerChange2( unsigned long refcon )
+{
+       // [deprecated] public
+       return kIOReturnUnsupported;
+}
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// OurChangeWaitForPowerSettle
+// [public] cancelPowerChange
 //
-// Our controlling driver has changed power state on the hardware
-// during a power change we initiated.  Here we see if we need to wait
-// for power to settle before continuing.  If not, we continue processing
-// (notifying interested parties post-change).  If so, we wait and
-// continue later.
+// Our power state is about to lower, and we have notified applications
+// and kernel clients, and one of them has vetoed the change.  If this is the last
+// client to respond, we abandon the power change.
 //*********************************************************************************
 
-void IOService::OurChangeWaitForPowerSettle ( void )
+IOReturn
+IOService::cancelPowerChange( unsigned long refcon )
 {
-    priv->settle_time = compute_settle_time();
-    if ( priv->settle_time == 0 ) 
-    {
-       OurChangeNotifyInterestedDriversDidChange();
-    } else {
-        priv->machine_state = kIOPM_OurChangeNotifyInterestedDriversDidChange;
-        startSettleTimer(priv->settle_time);
-    }
+       IOPMRequest *   request;
+       char            name[128];
+       pid_t           pid = proc_selfpid();
+
+       if (!initialized) {
+               // we're unloading
+               return kIOReturnSuccess;
+       }
+
+       name[0] = '\0';
+       proc_name(pid, name, sizeof(name));
+       PM_ERROR("PM notification cancel (pid %d, %s)\n", pid, name);
+
+       request = acquirePMRequest( this, kIOPMRequestTypeCancelPowerChange );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
+
+       request->fArg0 = (void *)            refcon;
+       request->fArg1 = (void *)(uintptr_t) proc_selfpid();
+       request->fArg2 = (void *)            OSString::withCString(name);
+       submitPMRequest( request );
+
+       return kIOReturnSuccess;
 }
 
-
 //*********************************************************************************
-// OurChangeNotifyInterestedDriversDidChange
+// cancelIdlePowerDown
 //
-// Power has settled on a power change we initiated.  Here we notify
-// all our interested parties post-change.  If they all acknowledge, we're
-// done with this change note, and we can start on the next one.
-// Otherwise we have to wait for acknowledgements and finish up later.
+// Internal method to trigger an idle cancel or revert
 //*********************************************************************************
 
-void IOService::OurChangeNotifyInterestedDriversDidChange ( void )
+void
+IOService::cancelIdlePowerDown( IOService * service )
 {
-    // in case they don't all ack
-    priv->machine_state = kIOPM_OurChangeFinish;
-    if ( notifyAll(false) == IOPMAckImplied ) 
-    {
-        // not waiting for responses
-        OurChangeFinish();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout
+       IOPMRequest * request;
+
+       request = acquirePMRequest(service, kIOPMRequestTypeIdleCancel);
+       if (request) {
+               submitPMRequest(request);
+       }
 }
 
+#ifndef __LP64__
+IOReturn
+IOService::serializedCancelPowerChange2( unsigned long refcon )
+{
+       // [deprecated] public
+       return kIOReturnUnsupported;
+}
 
 //*********************************************************************************
-// OurChangeFinish
+// PM_Clamp_Timer_Expired
 //
-// Power has settled on a power change we initiated, and
-// all our interested parties have acknowledged.  We're
-// done with this change note, and we can start on the next one.
+// called when clamp timer expires...set power state to 0.
 //*********************************************************************************
 
-void IOService::OurChangeFinish ( void )
+void
+IOService::PM_Clamp_Timer_Expired( void )
 {
-    all_done();
 }
 
-
 //*********************************************************************************
-// ParentDownTellPriorityClientsPowerDown_Immediate
+// clampPowerOn
 //
-// All applications and kernel clients have been notified of a power lowering
-// initiated by the parent and we didn't have to wait for any responses.  Here
-// we notify any priority clients.  If they all ack, we continue with the power change.
-// If at least one doesn't, we have to wait for it to acknowledge and then continue.
+// Set to highest available power state for a minimum of duration milliseconds
 //*********************************************************************************
 
-IOReturn IOService::ParentDownTellPriorityClientsPowerDown_Immediate ( void )
+void
+IOService::clampPowerOn( unsigned long duration )
 {
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentDownNotifyInterestedDriversWillChange_Delayed;
-    // are we waiting for responses?
-    if ( tellChangeDown2(priv->head_note_state) ) 
-    {
-        // no, notify interested drivers
-        return ParentDownNotifyInterestedDriversWillChange_Immediate();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // allowCancelCommon() or ack timeout
-    return IOPMWillAckLater;
 }
-
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// ParentDownTellPriorityClientsPowerDown_Immediate2
+//  configurePowerStateReport
 //
-// All priority kernel clients have been notified of a power lowering
-// initiated by the parent and we didn't have to wait for any responses.  Here
-// we notify any interested drivers and power domain children.  If they all ack,
-// we continue with the power change.
-// If at least one doesn't, we have to wait for it to acknowledge and then continue.
+//  Configures the IOStateReport for kPMPowerStateChannel
 //*********************************************************************************
-
-IOReturn IOService::ParentDownNotifyInterestedDriversWillChange_Immediate ( void )
+IOReturn
+IOService::configurePowerStatesReport( IOReportConfigureAction action, void *result )
 {
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentDownSetPowerState_Delayed;
-    if ( notifyAll(true) == IOPMAckImplied ) 
-    {
-        // they did
-        return ParentDownSetPowerState_Immediate();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout
-    return IOPMWillAckLater;
+       IOReturn rc = kIOReturnSuccess;
+       size_t  reportSize;
+       unsigned long i;
+       uint64_t                ts;
+
+       if (!pwrMgt) {
+               return kIOReturnUnsupported;
+       }
+
+       if (!fNumberOfPowerStates) {
+               return kIOReturnSuccess; // For drivers which are in power plane, but haven't called registerPowerDriver()
+       }
+       PM_LOCK();
+
+       switch (action) {
+       case kIOReportEnable:
+               if (fReportBuf) {
+                       fReportClientCnt++;
+                       break;
+               }
+               reportSize = STATEREPORT_BUFSIZE(fNumberOfPowerStates);
+               fReportBuf = IOMalloc(reportSize);
+               if (!fReportBuf) {
+                       rc = kIOReturnNoMemory;
+                       break;
+               }
+               memset(fReportBuf, 0, reportSize);
+
+               STATEREPORT_INIT(fNumberOfPowerStates, fReportBuf, reportSize,
+                   getRegistryEntryID(), kPMPowerStatesChID, kIOReportCategoryPower);
+
+               for (i = 0; i < fNumberOfPowerStates; i++) {
+                       unsigned bits = 0;
+
+                       if (fPowerStates[i].capabilityFlags & kIOPMPowerOn) {
+                               bits |= kPMReportPowerOn;
+                       }
+                       if (fPowerStates[i].capabilityFlags & kIOPMDeviceUsable) {
+                               bits |= kPMReportDeviceUsable;
+                       }
+                       if (fPowerStates[i].capabilityFlags & kIOPMLowPower) {
+                               bits |= kPMReportLowPower;
+                       }
+
+                       STATEREPORT_SETSTATEID(fReportBuf, i, ((bits & 0xff) << 8) |
+                           ((StateOrder(fMaxPowerState) & 0xf) << 4) | (StateOrder(i) & 0xf));
+               }
+               ts = mach_absolute_time();
+               STATEREPORT_SETSTATE(fReportBuf, fCurrentPowerState, ts);
+               break;
+
+       case kIOReportDisable:
+               if (fReportClientCnt == 0) {
+                       rc = kIOReturnBadArgument;
+                       break;
+               }
+               if (fReportClientCnt == 1) {
+                       IOFree(fReportBuf, STATEREPORT_BUFSIZE(fNumberOfPowerStates));
+                       fReportBuf = NULL;
+               }
+               fReportClientCnt--;
+               break;
+
+       case kIOReportGetDimensions:
+               if (fReportBuf) {
+                       STATEREPORT_UPDATERES(fReportBuf, kIOReportGetDimensions, result);
+               }
+               break;
+       }
+
+       PM_UNLOCK();
+
+       return rc;
 }
 
-
 //*********************************************************************************
-// ParentDownTellPriorityClientsPowerDown_Immediate4
+//  updatePowerStateReport
 //
-// All applications and kernel clients have been notified of a power lowering
-// initiated by the parent and we had to wait for responses.  Here
-// we notify any priority clients.  If they all ack, we continue with the power change.
-// If at least one doesn't, we have to wait for it to acknowledge and then continue.
+//  Updates the IOStateReport for kPMPowerStateChannel
 //*********************************************************************************
-
-void IOService::ParentDownTellPriorityClientsPowerDown_Delayed ( void )
+IOReturn
+IOService::updatePowerStatesReport( IOReportConfigureAction action, void *result, void *destination )
 {
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentDownNotifyInterestedDriversWillChange_Delayed;
-
-    // are we waiting for responses?
-    if ( tellChangeDown2(priv->head_note_state) ) 
-    {
-        // no, notify interested drivers
-        ParentDownNotifyInterestedDriversWillChange_Delayed();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // allowCancelCommon() or ack timeout
+       uint32_t size2cpy;
+       void *data2cpy;
+       uint64_t ts;
+       IOReturn rc = kIOReturnSuccess;
+       IOBufferMemoryDescriptor *dest = OSDynamicCast(IOBufferMemoryDescriptor, (OSObject *)destination);
+
+
+       if (!pwrMgt) {
+               return kIOReturnUnsupported;
+       }
+       if (!fNumberOfPowerStates) {
+               return kIOReturnSuccess;
+       }
+
+       if (!result || !dest) {
+               return kIOReturnBadArgument;
+       }
+       PM_LOCK();
+
+       switch (action) {
+       case kIOReportCopyChannelData:
+               if (!fReportBuf) {
+                       rc = kIOReturnNotOpen;
+                       break;
+               }
+
+               ts = mach_absolute_time();
+               STATEREPORT_UPDATEPREP(fReportBuf, ts, data2cpy, size2cpy);
+               if (size2cpy > (dest->getCapacity() - dest->getLength())) {
+                       rc = kIOReturnOverrun;
+                       break;
+               }
+
+               STATEREPORT_UPDATERES(fReportBuf, kIOReportCopyChannelData, result);
+               dest->appendBytes(data2cpy, size2cpy);
+               break;
+
+       default:
+               break;
+       }
+
+       PM_UNLOCK();
+
+       return rc;
 }
 
-
 //*********************************************************************************
-// ParentDownTellPriorityClientsPowerDown_Immediate5
+//  configureSimplePowerReport
 //
-// All applications and kernel clients have been notified of a power lowering
-// initiated by the parent and we had to wait for their responses.  Here we notify
-// any interested drivers and power domain children.  If they all ack, we continue
-// with the power change.
-// If at least one doesn't, we have to wait for it to acknowledge and then continue.
+//  Configures the IOSimpleReport for given channel id
 //*********************************************************************************
-
-void IOService::ParentDownNotifyInterestedDriversWillChange_Delayed ( void )
+IOReturn
+IOService::configureSimplePowerReport(IOReportConfigureAction action, void *result )
 {
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentDownSetPowerState_Delayed;
-    if ( notifyAll(true) == IOPMAckImplied ) 
-    {
-        // they did
-        ParentDownSetPowerState_Delayed();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout
-}
+       IOReturn rc = kIOReturnSuccess;
 
+       if (!pwrMgt) {
+               return kIOReturnUnsupported;
+       }
 
-//*********************************************************************************
-// ParentDownSetPowerState_Immediate
-//
-// All parties have acknowledged our pre-change notification of a power
-// lowering initiated by the parent.  Here we instruct our controlling driver
-// to put the hardware in the state it needs to be in when the domain is
-// lowered.  If it does so, we continue processing
-// (waiting for settle and acknowledging the parent.)
-// If it doesn't, we have to wait for it to acknowledge and then continue.
-//*********************************************************************************
+       if (!fNumberOfPowerStates) {
+               return rc;
+       }
 
-IOReturn IOService::ParentDownSetPowerState_Immediate ( void )
-{
-    priv->machine_state = kIOPM_ParentDownWaitForPowerSettle_Delayed;
+       switch (action) {
+       case kIOReportEnable:
+       case kIOReportDisable:
+               break;
+
+       case kIOReportGetDimensions:
+               SIMPLEREPORT_UPDATERES(kIOReportGetDimensions, result);
+               break;
+       }
 
-    if ( instruct_driver(priv->head_note_state) == IOPMAckImplied ) 
-    {
-        // it's done, carry on
-        return ParentDownWaitForPowerSettleAndNotifyDidChange_Immediate();
-    }
-    // it's not, wait for it
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,0,0);
-    start_ack_timer();
-    return IOPMWillAckLater;
-}
 
+       return rc;
+}
 
 //*********************************************************************************
-// ParentDownSetPowerState_Delayed
+//  updateSimplePowerReport
 //
-// We had to wait for it, but all parties have acknowledged our pre-change
-// notification of a power lowering initiated by the parent.
-// Here we instruct our controlling driver
-// to put the hardware in the state it needs to be in when the domain is
-// lowered.  If it does so, we continue processing
-// (waiting for settle and acknowledging the parent.)
-// If it doesn't, we have to wait for it to acknowledge and then continue.
+//  Updates the IOSimpleReport for the given chanel id
 //*********************************************************************************
-
-void IOService::ParentDownSetPowerState_Delayed ( void )
+IOReturn
+IOService::updateSimplePowerReport( IOReportConfigureAction action, void *result, void *destination )
 {
-    priv-> machine_state = kIOPM_ParentDownWaitForPowerSettle_Delayed;
-
-    if ( instruct_driver(priv->head_note_state) == IOPMAckImplied ) 
-    {
-        // it's done, carry on
-        ParentDownWaitForPowerSettle_Delayed();
-    } else {
-        // it's not, wait for it
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,0,0);
-        start_ack_timer();
-    }
+       uint32_t size2cpy;
+       void *data2cpy;
+       uint64_t buf[SIMPLEREPORT_BUFSIZE / sizeof(uint64_t) + 1]; // Force a 8-byte alignment
+       IOBufferMemoryDescriptor *dest = OSDynamicCast(IOBufferMemoryDescriptor, (OSObject *)destination);
+       IOReturn rc = kIOReturnSuccess;
+       unsigned bits = 0;
+
+
+       if (!pwrMgt) {
+               return kIOReturnUnsupported;
+       }
+       if (!result || !dest) {
+               return kIOReturnBadArgument;
+       }
+
+       if (!fNumberOfPowerStates) {
+               return rc;
+       }
+       PM_LOCK();
+
+       switch (action) {
+       case kIOReportCopyChannelData:
+
+               SIMPLEREPORT_INIT(buf, sizeof(buf), getRegistryEntryID(), kPMCurrStateChID, kIOReportCategoryPower);
+
+               if (fPowerStates[fCurrentPowerState].capabilityFlags & kIOPMPowerOn) {
+                       bits |= kPMReportPowerOn;
+               }
+               if (fPowerStates[fCurrentPowerState].capabilityFlags & kIOPMDeviceUsable) {
+                       bits |= kPMReportDeviceUsable;
+               }
+               if (fPowerStates[fCurrentPowerState].capabilityFlags & kIOPMLowPower) {
+                       bits |= kPMReportLowPower;
+               }
+
+
+               SIMPLEREPORT_SETVALUE(buf, ((bits & 0xff) << 8) | ((StateOrder(fMaxPowerState) & 0xf) << 4) |
+                   (StateOrder(fCurrentPowerState) & 0xf));
+
+               SIMPLEREPORT_UPDATEPREP(buf, data2cpy, size2cpy);
+               if (size2cpy > (dest->getCapacity() - dest->getLength())) {
+                       rc = kIOReturnOverrun;
+                       break;
+               }
+
+               SIMPLEREPORT_UPDATERES(kIOReportCopyChannelData, result);
+               dest->appendBytes(data2cpy, size2cpy);
+               break;
+
+       default:
+               break;
+       }
+
+       PM_UNLOCK();
+
+       return kIOReturnSuccess;
 }
 
 
+
+// MARK: -
+// MARK: Driver Overrides
+
 //*********************************************************************************
-// ParentDownWaitForPowerSettleAndNotifyDidChange_Immediate
+// [public] setPowerState
 //
-// Our controlling driver has changed power state on the hardware
-// during a power change initiated by our parent.  Here we see if we need
-// to wait for power to settle before continuing.  If not, we continue
-// processing (acknowledging our preparedness to the parent).
-// If so, we wait and continue later.
+// Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::ParentDownWaitForPowerSettleAndNotifyDidChange_Immediate ( void )
+IOReturn
+IOService::setPowerState(
+       unsigned long powerStateOrdinal, IOService * whatDevice )
 {
-    IOService * nub;
-    
-    priv->settle_time = compute_settle_time();
-    if ( priv->settle_time == 0 ) 
-    {
-        // store current state in case they don't all ack
-        priv->machine_state = kIOPM_ParentDownAcknowledgeChange_Delayed;
-        if ( notifyAll(false) == IOPMAckImplied ) 
-        {
-            // not waiting for responses
-            nub = priv->head_note_parent;
-            nub->retain();
-            all_done();
-            nub->release();
-            return IOPMAckImplied;
-        }
-        // If we are waiting for responses, execution will resume via 
-        // all_acked() or ack timeout        
-        return IOPMWillAckLater;
-   } else {
-        // let settle time elapse, then notify interest drivers of our power state change in ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed
-        priv->machine_state = kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed;
-        startSettleTimer(priv->settle_time);
-        return IOPMWillAckLater;
-   }
+       return IOPMNoErr;
 }
 
-
 //*********************************************************************************
-// ParentDownWaitForPowerSettle_Delayed
+// [public] maxCapabilityForDomainState
 //
-// Our controlling driver has changed power state on the hardware
-// during a power change initiated by our parent.  We have had to wait
-// for acknowledgement from interested parties, or we have had to wait
-// for the controlling driver to change the state.  Here we see if we need
-// to wait for power to settle before continuing.  If not, we continue
-// processing (acknowledging our preparedness to the parent).
-// If so, we wait and continue later.
+// Finds the highest power state in the array whose input power requirement
+// is equal to the input parameter. Where a more intelligent decision is
+// possible, override this in the subclassed driver.
 //*********************************************************************************
 
-void IOService::ParentDownWaitForPowerSettle_Delayed ( void )
+IOPMPowerStateIndex
+IOService::getPowerStateForDomainFlags( IOPMPowerFlags flags )
 {
-    priv->settle_time = compute_settle_time();
-    if ( priv->settle_time == 0 ) 
-    {
-        ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed();
-   } else {
-       priv->machine_state = kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed;
-       startSettleTimer(priv->settle_time);
-   }
+       IOPMPowerStateIndex stateIndex;
+
+       if (!fNumberOfPowerStates) {
+               return kPowerStateZero;
+       }
+
+       for (int order = fNumberOfPowerStates - 1; order >= 0; order--) {
+               stateIndex = fPowerStates[order].stateOrderToIndex;
+
+               if ((flags & fPowerStates[stateIndex].inputPowerFlags) ==
+                   fPowerStates[stateIndex].inputPowerFlags) {
+                       return stateIndex;
+               }
+       }
+       return kPowerStateZero;
 }
 
+unsigned long
+IOService::maxCapabilityForDomainState( IOPMPowerFlags domainState )
+{
+       return getPowerStateForDomainFlags(domainState);
+}
 
 //*********************************************************************************
-// ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed
+// [public] initialPowerStateForDomainState
 //
-// Power has settled on a power change initiated by our parent.  Here we
-// notify interested parties.
+// Called to query the power state for the initial power transition.
 //*********************************************************************************
 
-void IOService::ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed ( void )
+unsigned long
+IOService::initialPowerStateForDomainState( IOPMPowerFlags domainState )
 {
-    IORegistryEntry                         *nub;
-    IOService                               *parent;
+       if (fResetPowerStateOnWake && (domainState & kIOPMRootDomainState)) {
+               // Return lowest power state for any root power domain changes
+               return kPowerStateZero;
+       }
 
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentDownAcknowledgeChange_Delayed;
-    if ( notifyAll(false) == IOPMAckImplied ) {
-        nub = priv->head_note_parent;
-        nub->retain();
-        all_done();
-        parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-        if ( parent ) {
-            parent->acknowledgePowerChange((IOService *)nub);
-            parent->release();
-        }
-        nub->release();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout in ParentDownAcknowledgeChange_Delayed.
-    // Notice the duplication of code just above and in ParentDownAcknowledgeChange_Delayed.
+       return getPowerStateForDomainFlags(domainState);
 }
 
-
 //*********************************************************************************
-// ParentDownAcknowledgeChange_Delayed
+// [public] powerStateForDomainState
 //
-// We had to wait for it, but all parties have acknowledged our post-change
-// notification of a power  lowering initiated by the parent.
-// Here we acknowledge the parent.
-// We are done with this change note, and we can start on the next one.
+// This method is not called from PM.
 //*********************************************************************************
 
-void IOService::ParentDownAcknowledgeChange_Delayed ( void )
+unsigned long
+IOService::powerStateForDomainState( IOPMPowerFlags domainState )
 {
-    IORegistryEntry                         *nub;
-    IOService                               *parent;
-    
-    nub = priv->head_note_parent;
-    nub->retain();
-    all_done();
-    parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-    if ( parent ) 
-    {
-        parent->acknowledgePowerChange((IOService *)nub);
-        parent->release();
-    }
-    nub->release();
+       return getPowerStateForDomainFlags(domainState);
 }
 
-
+#ifndef __LP64__
 //*********************************************************************************
-// ParentUpSetPowerState_Delayed
+// [deprecated] didYouWakeSystem
 //
-// Our parent has informed us via powerStateDidChange that it has
-// raised the power in our power domain, and we have had to wait
-// for some interested party to acknowledge our notification.
-//   Here we instruct our controlling
-// driver to program the hardware to take advantage of the higher domain
-// power.  If it does so, we continue processing
-// (waiting for settle and notifying interested parties post-change.)
-// If it doesn't, we have to wait for it to acknowledge and then continue.
+// Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-void IOService::ParentUpSetPowerState_Delayed ( void )
+bool
+IOService::didYouWakeSystem( void )
 {
-    priv->machine_state = kIOPM_ParentUpWaitForSettleTime_Delayed;
-    if ( instruct_driver(priv->head_note_state) == IOPMAckImplied ) 
-    {
-        // it did it, carry on
-        ParentUpWaitForSettleTime_Delayed();
-    } else {
-        // it didn't, wait for it
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,0,0);
-        start_ack_timer();
-    }
+       return false;
 }
-
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// ParentUpSetPowerState_Immediate
+// [public] powerStateWillChangeTo
 //
-// Our parent has informed us via powerStateDidChange that it has
-// raised the power in our power domain.  Here we instruct our controlling
-// driver to program the hardware to take advantage of the higher domain
-// power.  If it does so, we continue processing
-// (waiting for settle and notifying interested parties post-change.)
-// If it doesn't, we have to wait for it to acknowledge and then continue.
+// Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::ParentUpSetPowerState_Immediate ( void )
+IOReturn
+IOService::powerStateWillChangeTo( IOPMPowerFlags, unsigned long, IOService * )
 {
-    priv->machine_state = kIOPM_ParentUpWaitForSettleTime_Delayed;
-
-    if ( instruct_driver(priv->head_note_state) == IOPMAckImplied ) 
-    {
-        // it did it, carry on
-        return ParentUpWaitForSettleTime_Immediate();
-    }
-    else {
-        // it didn't, wait for it
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,0,0);
-        start_ack_timer();
-        return IOPMWillAckLater;
-    }
+       return kIOPMAckImplied;
 }
 
-
 //*********************************************************************************
-// ParentUpWaitForSettleTime_Immediate
+// [public] powerStateDidChangeTo
 //
-// Our controlling driver has changed power state on the hardware
-// during a power raise initiated by the parent.  Here we see if we need to wait
-// for power to settle before continuing.  If not, we continue processing
-// (notifying interested parties post-change).  If so, we wait and
-// continue later.
+// Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::ParentUpWaitForSettleTime_Immediate ( void )
+IOReturn
+IOService::powerStateDidChangeTo( IOPMPowerFlags, unsigned long, IOService * )
 {
-    priv->settle_time = compute_settle_time();
-    if ( priv->settle_time == 0 ) 
-    {
-        return ParentUpNotifyInterestedDriversDidChange_Immediate();
-    } else {
-        priv->machine_state = kIOPM_ParentUpNotifyInterestedDriversDidChange_Delayed;
-        startSettleTimer(priv->settle_time);
-        return IOPMWillAckLater;
-    }
+       return kIOPMAckImplied;
 }
 
-
 //*********************************************************************************
-// ParentUpWaitForSettleTime_Delayed
+// [protected] powerChangeDone
 //
-// Our controlling driver has changed power state on the hardware
-// during a power raise initiated by the parent, but we had to wait for it.
-// Here we see if we need to wait for power to settle before continuing.
-// If not, we continue processing  (notifying interested parties post-change).
-// If so, we wait and continue later.
+// Called from PM work loop thread.
+// Does nothing here.  This should be implemented in a subclass policy-maker.
 //*********************************************************************************
 
-void IOService::ParentUpWaitForSettleTime_Delayed ( void )
+void
+IOService::powerChangeDone( unsigned long )
 {
-    priv->settle_time = compute_settle_time();
-    if ( priv->settle_time == 0 ) 
-    {
-        ParentUpNotifyInterestedDriversDidChange_Delayed();
-    } else {
-        priv->machine_state = kIOPM_ParentUpNotifyInterestedDriversDidChange_Delayed;
-        startSettleTimer(priv->settle_time);
-    }
 }
 
-
+#ifndef __LP64__
 //*********************************************************************************
-// ParentUpNotifyInterestedDriversDidChange_Immediate
+// [deprecated] newTemperature
 //
-// No power settling was required on a power raise initiated by the parent.
-// Here we notify all our interested parties post-change.  If they all acknowledge,
-// we're done with this change note, and we can start on the next one.
-// Otherwise we have to wait for acknowledgements and finish up later.
+// Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::ParentUpNotifyInterestedDriversDidChange_Immediate ( void )
+IOReturn
+IOService::newTemperature( long currentTemp, IOService * whichZone )
 {
-    IOService * nub;
-    
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentUpAcknowledgePowerChange_Delayed;
-    if ( notifyAll(false) == IOPMAckImplied ) 
-    {
-        nub = priv->head_note_parent;
-        nub->retain();
-        all_done();
-        nub->release();
-        return IOPMAckImplied;
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout in ParentUpAcknowledgePowerChange_Delayed.
-    return IOPMWillAckLater;
+       return IOPMNoErr;
 }
-
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// ParentUpNotifyInterestedDriversDidChange_Delayed
+// [public] systemWillShutdown
 //
-// Power has settled on a power raise initiated by the parent.
-// Here we notify all our interested parties post-change.  If they all acknowledge,
-// we're done with this change note, and we can start on the next one.
-// Otherwise we have to wait for acknowledgements and finish up later.
+// System shutdown and restart notification.
 //*********************************************************************************
 
-void IOService::ParentUpNotifyInterestedDriversDidChange_Delayed ( void )
+void
+IOService::systemWillShutdown( IOOptionBits specifier )
 {
-    // in case they don't all ack
-    priv->machine_state = kIOPM_ParentUpAcknowledgePowerChange_Delayed;
-    if ( notifyAll(false) == IOPMAckImplied ) 
-    {
-        ParentUpAcknowledgePowerChange_Delayed();
-    }
-    // If we are waiting for responses, execution will resume via 
-    // all_acked() or ack timeout in ParentUpAcknowledgePowerChange_Delayed.
+       IOPMrootDomain * rootDomain = IOService::getPMRootDomain();
+       if (rootDomain) {
+               rootDomain->acknowledgeSystemWillShutdown( this );
+       }
 }
 
+// MARK: -
+// MARK: PM State Machine
 
 //*********************************************************************************
-// ParentUpAcknowledgePowerChange_Delayed
-//
-// All parties have acknowledged our post-change notification of a power
-// raising initiated by the parent.  Here we acknowledge the parent.
-// We are done with this change note, and we can start on the next one.
-//*********************************************************************************
-
-void IOService::ParentUpAcknowledgePowerChange_Delayed ( void )
-{
-    IORegistryEntry                         *nub;
-    IOService                               *parent;
-    
-    nub = priv->head_note_parent;
-    nub->retain();
-    all_done();
-    parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-    if ( parent ) 
-    {
-        parent->acknowledgePowerChange((IOService *)nub);
-        parent->release();
-    }
-    nub->release();
-}
-
-
-//*********************************************************************************
-// all_done
-//
-// A power change is complete, and the used post-change note is at
-// the head of the queue.  Remove it and set myCurrentState to the result
-// of the change.  Start up the next change in queue.
-//*********************************************************************************
-
-void IOService::all_done ( void )
-{
-    unsigned long                           previous_state;
-    IORegistryEntry                         *nub;
-    IOService                               *parent;
-    
-    priv->machine_state = kIOPM_Finished;
-
-    // our power change
-    if ( priv->head_note_flags & IOPMWeInitiated ) 
-    {
-        // could our driver switch to the new state?
-        if ( !( priv->head_note_flags & IOPMNotDone) ) 
-        {
-            // yes, did power raise?
-            if ( pm_vars->myCurrentState < priv->head_note_state ) 
-            {
-                // yes, inform clients and apps
-                tellChangeUp (priv->head_note_state);
-            } else {
-                // no, if this lowers our
-                if ( !  priv->we_are_root ) 
-                {
-                    // power requirements, tell the parent
-                    ask_parent(priv->head_note_state);
-                }
-            }
-            previous_state = pm_vars->myCurrentState;
-            // either way
-            pm_vars->myCurrentState = priv->head_note_state;
-            priv->imminentState = pm_vars->myCurrentState;
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogChangeDone,(unsigned long)pm_vars->myCurrentState,0);
-            // inform subclass policy-maker
-            powerChangeDone(previous_state);
-        }
-    }
-
-    // parent's power change
-    if ( priv->head_note_flags & IOPMParentInitiated) 
-    {
-        if ( ((priv->head_note_flags & IOPMDomainWillChange) && (pm_vars->myCurrentState >= priv->head_note_state)) ||
-                 ((priv->head_note_flags & IOPMDomainDidChange) && (pm_vars->myCurrentState < priv->head_note_state)) ) 
-        {
-            // did power raise?
-            if ( pm_vars->myCurrentState < priv->head_note_state ) 
-            {
-                // yes, inform clients and apps
-                tellChangeUp (priv->head_note_state);
-            }
-            // either way
-            previous_state = pm_vars->myCurrentState;
-            pm_vars->myCurrentState = priv->head_note_state;
-            priv->imminentState = pm_vars->myCurrentState;
-            pm_vars->maxCapability = pm_vars->theControllingDriver->maxCapabilityForDomainState(priv->head_note_domainState);
-
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogChangeDone,(unsigned long)pm_vars->myCurrentState,0);
-            // inform subclass policy-maker
-            powerChangeDone(previous_state);
-        }
-    }
-
-    IOLockLock(priv->queue_lock);
-    // we're done with this
-    priv->changeList->releaseHeadChangeNote();
-        
-    // start next one in queue
-    priv->head_note = priv->changeList->currentChange();
-    if ( priv->head_note != -1 ) 
-    {
-
-        IOLockUnlock(priv->queue_lock);
-        if (priv->changeList->changeNote[priv->head_note].flags & IOPMWeInitiated ) 
-        {
-            start_our_change(priv->head_note);
-        } else {
-            nub = priv->changeList->changeNote[priv->head_note].parent;
-            if ( start_parent_change(priv->head_note) == IOPMAckImplied ) 
-            {
-                parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-                if ( parent ) 
-                {
-                    parent->acknowledgePowerChange((IOService *)nub);
-                    parent->release();
-                }
-            }
-        }
-    } else {
-        IOLockUnlock(priv->queue_lock);
-    }
-}
-
-
-
-//*********************************************************************************
-// all_acked
-//
-// A driver or child has acknowledged our notification of an upcoming power
-// change, and this acknowledgement is the last one pending
-// before we change power or after changing power.
-//
-//*********************************************************************************
-
-void IOService::all_acked ( void )
-{
-    switch (priv->machine_state) {
-       case kIOPM_OurChangeSetPowerState:
-           OurChangeSetPowerState();
-           break;
-       case kIOPM_OurChangeFinish:
-           OurChangeFinish();
-           break;
-       case kIOPM_ParentDownSetPowerState_Delayed:
-           ParentDownSetPowerState_Delayed();  
-           break;
-       case kIOPM_ParentDownAcknowledgeChange_Delayed:
-           ParentDownAcknowledgeChange_Delayed();
-           break;
-       case kIOPM_ParentUpSetPowerState_Delayed:
-           ParentUpSetPowerState_Delayed();
-           break;
-       case kIOPM_ParentUpAcknowledgePowerChange_Delayed:
-           ParentUpAcknowledgePowerChange_Delayed();
-           break;
-   }
-}
-
-//*********************************************************************************
-// settleTimerExpired
-//
-// Power has settled after our last change.  Notify interested parties that
-// there is a new power state.
+// [private static] acquirePMRequest
 //*********************************************************************************
 
-void IOService::settleTimerExpired ( void )
+IOPMRequest *
+IOService::acquirePMRequest( IOService * target, IOOptionBits requestType,
+    IOPMRequest * active )
 {
-    if ( ! initialized ) 
-    {
-        // we're unloading
-        return;
-    }
-
-    switch (priv->machine_state) {
-        case kIOPM_OurChangeNotifyInterestedDriversDidChange:
-            OurChangeNotifyInterestedDriversDidChange();
-            break;
-        case kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed:
-            ParentDownNotifyDidChangeAndAcknowledgeChange_Delayed();
-            break;
-        case kIOPM_ParentUpNotifyInterestedDriversDidChange_Delayed:
-            ParentUpNotifyInterestedDriversDidChange_Delayed();
-            break;
-    }
+       IOPMRequest * request;
+
+       assert(target);
+
+       request = IOPMRequest::create();
+       if (request) {
+               request->init( target, requestType );
+               if (active) {
+                       IOPMRequest * root = active->getRootRequest();
+                       if (root) {
+                               request->attachRootRequest(root);
+                       }
+               }
+       } else {
+               PM_ERROR("%s: No memory for PM request type 0x%x\n",
+                   target->getName(), (uint32_t) requestType);
+       }
+       return request;
 }
 
-
 //*********************************************************************************
-// compute_settle_time
-//
-// Compute the power-settling delay in microseconds for the
-// change from myCurrentState to head_note_state.
+// [private static] releasePMRequest
 //*********************************************************************************
 
-unsigned long IOService::compute_settle_time ( void )
+void
+IOService::releasePMRequest( IOPMRequest * request )
 {
-    unsigned long                           totalTime;
-    unsigned long                           i;
-
-    // compute total time to attain the new state
-    totalTime = 0;
-    i = pm_vars->myCurrentState;
-
-    // we're lowering power
-    if ( priv->head_note_state < pm_vars->myCurrentState ) 
-    {
-        while ( i > priv->head_note_state ) 
-        {
-            totalTime +=  pm_vars->thePowerStates[i].settleDownTime;
-            i--;
-        }
-    }
-
-    // we're raising power
-    if ( priv->head_note_state > pm_vars->myCurrentState ) 
-    {
-        while ( i < priv->head_note_state ) 
-        {
-            totalTime +=  pm_vars->thePowerStates[i+1].settleUpTime;
-            i++;
-        }
-    }
-
-    return totalTime;
+       if (request) {
+               request->reset();
+               request->release();
+       }
 }
 
-
 //*********************************************************************************
-// startSettleTimer
-//
-// Enter with a power-settling delay in microseconds and start a nano-second
-// timer for that delay.
+// [private static] submitPMRequest
 //*********************************************************************************
 
-IOReturn IOService::startSettleTimer ( unsigned long delay )
+void
+IOService::submitPMRequest( IOPMRequest * request )
 {
-    AbsoluteTime       deadline;
-    
-    clock_interval_to_deadline(delay, kMicrosecondScale, &deadline);
-
-    thread_call_enter_delayed(priv->settleTimer, deadline);
+       assert( request );
+       assert( gIOPMReplyQueue );
+       assert( gIOPMRequestQueue );
+
+       PM_LOG1("[+ %02lx] %p [%p %s] %p %p %p\n",
+           (long)request->getType(), OBFUSCATE(request),
+           OBFUSCATE(request->getTarget()), request->getTarget()->getName(),
+           OBFUSCATE(request->fArg0),
+           OBFUSCATE(request->fArg1), OBFUSCATE(request->fArg2));
+
+       if (request->isReplyType()) {
+               gIOPMReplyQueue->queuePMRequest( request );
+       } else {
+               gIOPMRequestQueue->queuePMRequest( request );
+       }
+}
 
-    return IOPMNoErr;
+void
+IOService::submitPMRequests( IOPMRequest ** requests, IOItemCount count )
+{
+       assert( requests );
+       assert( count > 0 );
+       assert( gIOPMRequestQueue );
+
+       for (IOItemCount i = 0; i < count; i++) {
+               IOPMRequest * req = requests[i];
+               PM_LOG1("[+ %02lx] %p [%p %s] %p %p %p\n",
+                   (long)req->getType(), OBFUSCATE(req),
+                   OBFUSCATE(req->getTarget()), req->getTarget()->getName(),
+                   OBFUSCATE(req->fArg0),
+                   OBFUSCATE(req->fArg1), OBFUSCATE(req->fArg2));
+       }
+
+       gIOPMRequestQueue->queuePMRequestChain( requests, count );
 }
 
 //*********************************************************************************
-// ack_timer_ticked
+// [private] actionPMRequestQueue
 //
-// The acknowledgement timeout periodic timer has ticked.
-// If we are awaiting acks for a power change notification,
-// we decrement the timer word of each interested driver which hasn't acked.
-// If a timer word becomes zero, we pretend the driver aknowledged.
-// If we are waiting for the controlling driver to change the power
-// state of the hardware, we decrement its timer word, and if it becomes
-// zero, we pretend the driver acknowledged.
+// IOPMRequestQueue::checkForWork() passing a new request to the request target.
 //*********************************************************************************
 
-void IOService::ack_timer_ticked ( void )
-{
-    IOPMinformee * nextObject;
-
-    if ( ! initialized ) 
-    {
-        // we're unloading
-        return;
-    }
-
-    if (! acquire_lock() ) 
-    {
-        return;
-    }
-    
-    switch (priv->machine_state) {
-        case kIOPM_OurChangeWaitForPowerSettle:
-        case kIOPM_ParentDownWaitForPowerSettle_Delayed:
-        case kIOPM_ParentUpWaitForSettleTime_Delayed:
-            // are we waiting for our driver to make its change?
-            if ( priv->driver_timer != 0 ) {
-                // yes, tick once
-                priv->driver_timer -= 1;
-                // it's tardy, we'll go on without it
-                if ( priv->driver_timer == 0 ) 
-                {
-                    IOUnlock(priv->our_lock);
-                    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogCtrlDriverTardy,0,0);
-                    driver_acked();
-                } else {
-                    // still waiting, set timer again
-                    start_ack_timer();
-                    IOUnlock(priv->our_lock);
-                }
-            }
-            else {
-                IOUnlock(priv->our_lock);
-            }
-            break;
-
-        case kIOPM_OurChangeSetPowerState:
-        case kIOPM_OurChangeFinish:
-        case kIOPM_ParentDownSetPowerState_Delayed:
-        case kIOPM_ParentDownAcknowledgeChange_Delayed:
-        case kIOPM_ParentUpSetPowerState_Delayed:
-        case kIOPM_ParentUpAcknowledgePowerChange_Delayed:
-            // are we waiting for interested parties to acknowledge?
-            if (priv->head_note_pendingAcks != 0 ) 
-            {
-                // yes, go through the list of interested drivers
-                nextObject =  priv->interestedDrivers->firstInList();
-                // and check each one
-                while (  nextObject != NULL ) 
-                {
-                    if ( nextObject->timer > 0 ) 
-                    {
-                        nextObject->timer -= 1;
-                        // this one should have acked by now
-                        if ( nextObject->timer == 0 ) 
-                        {
-                            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogIntDriverTardy,0,0);
-                            //kprintf("interested driver tardy: %s\n",nextObject->whatObject->getName());
-                            priv->head_note_pendingAcks -= 1;
-                        }
-                    }
-                    nextObject  =  priv->interestedDrivers->nextInList(nextObject);
-                }
-
-                // is that the last?
-                if ( priv->head_note_pendingAcks == 0 ) 
-                {
-                    IOUnlock(priv->our_lock);
-                    // yes, we can continue
-                    all_acked();
-                } else {
-                    // no, set timer again
-                    start_ack_timer();
-                    IOUnlock(priv->our_lock);
-                }
-            } else {
-                IOUnlock(priv->our_lock);
-            }
-            break;
-
-        // apps didn't respond to parent-down notification
-        case kIOPM_ParentDownTellPriorityClientsPowerDown_Immediate:
-            IOUnlock(priv->our_lock);
-            IOLockLock(priv->flags_lock);
-            if (pm_vars->responseFlags) 
-            {
-                // get rid of this stuff
-                pm_vars->responseFlags->release();
-                pm_vars->responseFlags = NULL;
-            }
-            IOLockUnlock(priv->flags_lock);
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientTardy,0,5);
-            // carry on with the change
-            ParentDownTellPriorityClientsPowerDown_Delayed();
-            break;
-            
-        case kIOPM_ParentDownNotifyInterestedDriversWillChange_Delayed:
-            IOUnlock(priv->our_lock);
-            IOLockLock(priv->flags_lock);
-            if (pm_vars->responseFlags) 
-            {
-                // get rid of this stuff
-                pm_vars->responseFlags->release();
-                pm_vars->responseFlags = NULL;
-            }
-            IOLockUnlock(priv->flags_lock);
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientTardy,0,1);
-            // carry on with the change
-            ParentDownNotifyInterestedDriversWillChange_Delayed();
-            break;
-            
-        case kIOPM_OurChangeTellClientsPowerDown:
-            // apps didn't respond to our power-down request
-            IOUnlock(priv->our_lock);
-            IOLockLock(priv->flags_lock);
-            if (pm_vars->responseFlags) 
-            {
-                // get rid of this stuff
-                pm_vars->responseFlags->release();
-                pm_vars->responseFlags = NULL;
-            }
-            IOLockUnlock(priv->flags_lock);
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientTardy,0,2);
-            // rescind the request
-            tellNoChangeDown(priv->head_note_state);
-            // mark the change note un-actioned
-            priv->head_note_flags |= IOPMNotDone;
-            // and we're done
-            all_done();
-            break;
-            
-        case kIOPM_OurChangeTellPriorityClientsPowerDown:
-            // clients didn't respond to our power-down note
-            IOUnlock(priv->our_lock);
-            IOLockLock(priv->flags_lock);
-            if (pm_vars->responseFlags) 
-            {
-                // get rid of this stuff
-                pm_vars->responseFlags->release();
-                pm_vars->responseFlags = NULL;
-            }
-            IOLockUnlock(priv->flags_lock);
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientTardy,0,4);
-            // carry on with the change
-            OurChangeTellPriorityClientsPowerDown();
-            break;
-            
-        case kIOPM_OurChangeNotifyInterestedDriversWillChange:
-             // apps didn't respond to our power-down notification
-            IOUnlock(priv->our_lock);
-            IOLockLock(priv->flags_lock);
-            if (pm_vars->responseFlags) 
-            {
-                // get rid of this stuff
-                pm_vars->responseFlags->release();
-                pm_vars->responseFlags = NULL;
-            }
-            IOLockUnlock(priv->flags_lock);
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientTardy,0,3);
-            // carry on with the change
-            OurChangeNotifyInterestedDriversWillChange();
-            break;
-            
-        default:
-            // not waiting for acks
-            IOUnlock(priv->our_lock);
-            break;
-    }
-}
-
-
-//*********************************************************************************
-// start_ack_timer
-//
-//*********************************************************************************
-
-void IOService::start_ack_timer ( void )
-{
-    AbsoluteTime                            deadline;
-
-    clock_interval_to_deadline(ACK_TIMER_PERIOD, kNanosecondScale, &deadline);
-    
-    thread_call_enter_delayed(priv->ackTimer, deadline);
-}
-
-
-//*********************************************************************************
-// stop_ack_timer
-//
-//*********************************************************************************
-
-void IOService::stop_ack_timer ( void )
-{
-    thread_call_cancel(priv->ackTimer);
-}
-
-
-//*********************************************************************************
-// c-language timer expiration functions
-//
-//*********************************************************************************
-
-static void ack_timer_expired ( thread_call_param_t us)
-{
-    ((IOService *)us)->ack_timer_ticked();
-}
-
-
-static void settle_timer_expired ( thread_call_param_t us)
-{
-    ((IOService *)us)->settleTimerExpired();
-}
-
-
-//*********************************************************************************
-// add_child_to_active_change
-//
-// A child has just registered with us.  If there is
-// currently a change in progress, get the new party involved: if we
-// have notified all parties and are waiting for acks, notify the new
-// party.
-//*********************************************************************************
-
-IOReturn IOService::add_child_to_active_change ( IOPowerConnection * newObject )
-{
-    if (! acquire_lock() ) 
-    {
-        return IOPMNoErr;
-    }
-
-    switch (priv->machine_state) 
-    {
-        case kIOPM_OurChangeSetPowerState:
-        case kIOPM_ParentDownSetPowerState_Delayed:
-        case kIOPM_ParentUpSetPowerState_Delayed:
-            // one for this child and one to prevent
-            priv->head_note_pendingAcks += 2;
-            // incoming acks from changing our state
-            IOUnlock(priv->our_lock);
-            notifyChild(newObject, true);
-            if (! acquire_lock() ) 
-            {
-                // put it back
-                --priv->head_note_pendingAcks;
-                return IOPMNoErr;
-            }
-            // are we still waiting for acks?
-            if ( --priv->head_note_pendingAcks == 0 ) 
-            {
-                // no, stop the timer
-                stop_ack_timer();
-                IOUnlock(priv->our_lock);
-                
-                // and now we can continue
-                all_acked();
-                return IOPMNoErr;
-            }
-            break;
-        case kIOPM_OurChangeFinish:
-        case kIOPM_ParentDownAcknowledgeChange_Delayed:
-        case kIOPM_ParentUpAcknowledgePowerChange_Delayed:
-            // one for this child and one to prevent
-            priv->head_note_pendingAcks += 2;
-            // incoming acks from changing our state
-            IOUnlock(priv->our_lock);
-            notifyChild(newObject, false);
-            if (! acquire_lock() ) 
-            {
-                // put it back
-                --priv->head_note_pendingAcks;
-                return IOPMNoErr;
-            }
-            // are we still waiting for acks?
-            if ( --priv->head_note_pendingAcks == 0 ) 
-            {
-                // no, stop the timer
-                stop_ack_timer();
-                IOUnlock(priv->our_lock);
-
-                // and now we can continue
-                all_acked();
-                return IOPMNoErr;
-            }
-            break;
-    }
-    IOUnlock(priv->our_lock);
-    return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// add_driver_to_active_change
-//
-// An interested driver has just registered with us.  If there is
-// currently a change in progress, get the new party involved: if we
-// have notified all parties and are waiting for acks, notify the new
-// party.
-//*********************************************************************************
-
-IOReturn IOService::add_driver_to_active_change ( IOPMinformee * newObject )
-{
-    if (! acquire_lock() ) 
-    {
-        return IOPMNoErr;
-    }
-
-    switch (priv->machine_state) {
-        case kIOPM_OurChangeSetPowerState:
-        case kIOPM_ParentDownSetPowerState_Delayed:
-        case kIOPM_ParentUpSetPowerState_Delayed:
-            // one for this driver and one to prevent
-            priv->head_note_pendingAcks += 2;
-            // incoming acks from changing our state
-            IOUnlock(priv->our_lock);
-            // inform the driver
-            inform(newObject, true);
-            if (! acquire_lock() ) 
-            {
-                // put it back
-                --priv->head_note_pendingAcks;
-                return IOPMNoErr;
-            }
-            // are we still waiting for acks?
-            if ( --priv->head_note_pendingAcks == 0 ) 
-            {
-                // no, stop the timer
-                stop_ack_timer();
-                IOUnlock(priv->our_lock);
-
-                // and now we can continue
-                all_acked();
-                return IOPMNoErr;
-            }
-            break;
-        case kIOPM_OurChangeFinish:
-        case kIOPM_ParentDownAcknowledgeChange_Delayed:
-        case kIOPM_ParentUpAcknowledgePowerChange_Delayed:
-            // one for this driver and one to prevent
-            priv->head_note_pendingAcks += 2;
-            // incoming acks from changing our state
-            IOUnlock(priv->our_lock);
-            // inform the driver
-            inform(newObject, false);
-            if (! acquire_lock() ) {
-                // put it back
-                --priv->head_note_pendingAcks;
-                return IOPMNoErr;
-            }
-            // are we still waiting for acks?
-            if ( --priv->head_note_pendingAcks == 0 ) {
-                // no, stop the timer
-                stop_ack_timer();
-                IOUnlock(priv->our_lock);
-
-                // and now we can continue
-                all_acked();
-                return IOPMNoErr;
-            }
-            break;
-    }
-    IOUnlock(priv->our_lock);
-    return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// start_parent_change
-//
-// Here we begin the processing of a change note  initiated by our parent
-// which is at the head of the queue.
-//
-// It is possible for the change to be processed to completion and removed from the queue.
-// There are several possible interruptions to the processing, though, and they are:
-// we may have to wait for interested parties to acknowledge our pre-change notification,
-// we may have to wait for our controlling driver to change the hardware power state,
-// there may be a settling time after changing the hardware power state,
-// we may have to wait for interested parties to acknowledge our post-change notification,
-// we may have to wait for the acknowledgement timer expiration to substitute for the
-// acknowledgement from a failing driver.
-//*********************************************************************************
-
-IOReturn IOService::start_parent_change ( unsigned long queue_head )
-{
-    priv->head_note = queue_head;
-    priv->head_note_flags = priv-> changeList->changeNote[priv->head_note].flags;
-    priv->head_note_state =  priv->changeList->changeNote[priv->head_note].newStateNumber;
-    priv->imminentState = priv->head_note_state;
-    priv->head_note_outputFlags =  priv->changeList->changeNote[priv->head_note].outputPowerCharacter;
-    priv->head_note_domainState = priv->changeList->changeNote[priv->head_note].domainState;
-    priv->head_note_parent = priv->changeList->changeNote[priv->head_note].parent;
-    priv->head_note_capabilityFlags =  priv->changeList->changeNote[priv->head_note].capabilityFlags;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartParentChange,
-                    (unsigned long)priv->head_note_state,(unsigned long)pm_vars->myCurrentState);
-
-    // if we need something and haven't told the parent, do so
-    ask_parent( priv->ourDesiredPowerState);
-
-    // power domain is lowering
-    if ( priv->head_note_state < pm_vars->myCurrentState ) 
-    {
-        setParentInfo(priv->changeList->changeNote[priv->head_note].singleParentState,priv->head_note_parent);
-       priv->initial_change = false;
-       // tell apps and kernel clients
-        priv->machine_state = kIOPM_ParentDownTellPriorityClientsPowerDown_Immediate;
-
-        // are we waiting for responses?
-        if ( tellChangeDown1(priv->head_note_state) ) 
-        {
-            // no, notify priority clients
-            return ParentDownTellPriorityClientsPowerDown_Immediate();
-        }
-        // yes
-        return IOPMWillAckLater;
-    }
-
-    // parent is raising power, we may or may not
-    if ( priv->head_note_state > pm_vars->myCurrentState ) 
-    {
-        if ( priv->ourDesiredPowerState > pm_vars->myCurrentState ) 
-        {
-            if ( priv->ourDesiredPowerState < priv->head_note_state ) 
-            {
-                // we do, but not all the way
-                priv->head_note_state = priv->ourDesiredPowerState;
-                priv->imminentState = priv->head_note_state;
-                priv->head_note_outputFlags =   pm_vars->thePowerStates[priv->head_note_state].outputPowerCharacter;
-                priv->head_note_capabilityFlags =   pm_vars->thePowerStates[priv->head_note_state].capabilityFlags;
-                pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAmendParentChange,(unsigned long)priv->head_note_state,0);
-             }
-        } else {
-            // we don't
-            priv->head_note_state = pm_vars->myCurrentState;
-            priv->imminentState = priv->head_note_state;
-            priv->head_note_outputFlags =   pm_vars->thePowerStates[priv->head_note_state].outputPowerCharacter;
-            priv->head_note_capabilityFlags =   pm_vars->thePowerStates[priv->head_note_state].capabilityFlags;
-            pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAmendParentChange,(unsigned long)priv->head_note_state,0);
-        }
-    }
-
-    if ( (priv->head_note_state > pm_vars->myCurrentState) &&
-                    (priv->head_note_flags & IOPMDomainDidChange) ) 
-    {
-        // changing up
-        priv->initial_change = false;
-        priv->machine_state = kIOPM_ParentUpSetPowerState_Delayed;
-        if (  notifyAll(true) == IOPMAckImplied ) {
-            return ParentUpSetPowerState_Immediate();
-        }
-        // they didn't all ack
-        return IOPMWillAckLater;
-    }
-
-    all_done();
-    // a null change or power will go up
-    return IOPMAckImplied;
-}
-
-
-//*********************************************************************************
-// start_our_change
-//
-// Here we begin the processing of a change note  initiated by us
-// which is at the head of the queue.
-//
-// It is possible for the change to be processed to completion and removed from the queue.
-// There are several possible interruptions to the processing, though, and they are:
-// we may have to wait for interested parties to acknowledge our pre-change notification,
-// changes initiated by the parent will wait in the middle for powerStateDidChange,
-// we may have to wait for our controlling driver to change the hardware power state,
-// there may be a settling time after changing the hardware power state,
-// we may have to wait for interested parties to acknowledge our post-change notification,
-// we may have to wait for the acknowledgement timer expiration to substitute for the
-// acknowledgement from a failing driver.
-//*********************************************************************************
-
-void IOService::start_our_change ( unsigned long queue_head )
-{
-    priv->head_note = queue_head;
-    priv->head_note_flags =  priv->changeList->changeNote[priv->head_note].flags;
-    priv->head_note_state =  priv->changeList->changeNote[priv->head_note].newStateNumber;
-    priv->imminentState = priv->head_note_state;
-    priv->head_note_outputFlags =  priv->changeList->changeNote[priv->head_note].outputPowerCharacter;
-    priv->head_note_capabilityFlags =  priv->changeList->changeNote[priv->head_note].capabilityFlags;
-
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartDeviceChange,
-                (unsigned long)priv->head_note_state,(unsigned long)pm_vars->myCurrentState);
-
-    // can our driver switch to the new state?
-    if ( priv->head_note_capabilityFlags & IOPMNotAttainable ) 
-    {
-        // no, ask the parent to do it then
-        if ( !  priv->we_are_root )
-        {
-            ask_parent(priv->head_note_state);
-        }
-        // mark the change note un-actioned
-        priv-> head_note_flags |= IOPMNotDone;
-        // and we're done
-        all_done();
-        return;
-    }
-    
-    // is there enough power in the domain?
-    if ( (pm_vars->maxCapability < priv->head_note_state) && (!  priv->we_are_root) ) 
-    {
-        // no, ask the parent to raise it
-        if ( !  priv->we_are_root ) 
-        {
-            ask_parent(priv->head_note_state);
-        }
-        // no, mark the change note un-actioned
-        priv->head_note_flags |= IOPMNotDone;
-        // and we're done
-        // till the parent raises power
-        all_done();
-        return;
-    }
-
-    if ( !  priv->initial_change ) 
-    {
-        if ( priv->head_note_state == pm_vars->myCurrentState ) 
-        {
-            // we initiated a null change; forget it
-            all_done();
-            return;
-        }
-    }
-    priv->initial_change = false;
-
-    // dropping power?
-    if ( priv->head_note_state < pm_vars->myCurrentState ) 
-    {
-        // yes, in case we have to wait for acks
-        priv->machine_state = kIOPM_OurChangeTellClientsPowerDown;
-        pm_vars->doNotPowerDown = false;
-
-        // ask apps and kernel clients if we can drop power
-        pm_vars->outofbandparameter = kNotifyApps;
-        if ( askChangeDown(priv->head_note_state) ) 
-        {
-            // don't have to wait, did any clients veto?
-            if ( pm_vars->doNotPowerDown ) 
-            {
-                // yes, rescind the warning
-                tellNoChangeDown(priv->head_note_state);
-                // mark the change note un-actioned
-                priv-> head_note_flags |= IOPMNotDone;
-                // and we're done
-                all_done();
-            } else {
-                // no, tell'em we're dropping power
-                OurChangeTellClientsPowerDown();
-            }
-        }
-    } else {
-        // we are raising power
-        if ( !  priv->we_are_root ) 
-        {
-            // if this changes our power requirement, tell the parent
-            ask_parent(priv->head_note_state);
-        }
-        // in case they don't all ack
-        priv->machine_state = kIOPM_OurChangeSetPowerState;
-
-        // notify interested drivers and children
-        if ( notifyAll(true) == IOPMAckImplied ) 
-        {
-            OurChangeSetPowerState();
-        }
-    }
-}
-
-
-//*********************************************************************************
-// ask_parent
-//
-// Call the power domain parent to ask for a higher power state in the domain
-// or to suggest a lower power state.
-//*********************************************************************************
-
-IOReturn IOService::ask_parent ( unsigned long requestedState )
-{
-    OSIterator                          *iter;
-    OSObject                            *next;
-    IOPowerConnection                   *connection;
-    IOService                           *parent;
-    unsigned long                       ourRequest = pm_vars->thePowerStates[requestedState].inputPowerRequirement;
-
-    if ( pm_vars->thePowerStates[requestedState].capabilityFlags & (kIOPMChildClamp | kIOPMPreventIdleSleep) ) 
-    {
-        ourRequest |= kIOPMPreventIdleSleep;
-    }
-    if ( pm_vars->thePowerStates[requestedState].capabilityFlags & (kIOPMChildClamp2 | kIOPMPreventSystemSleep) ) 
-    {
-        ourRequest |= kIOPMPreventSystemSleep;
-    }
-    
-    // is this a new desire?
-    if ( priv->previousRequest == ourRequest )
-    {  
-        // no, the parent knows already, just return
-        return IOPMNoErr;                              
-    }
-
-    if (  priv->we_are_root ) 
-    {
-        return IOPMNoErr;
-    }
-    priv->previousRequest =  ourRequest;
-
-    iter = getParentIterator(gIOPowerPlane);
-
-    if ( iter ) 
-    {
-        while ( (next = iter->getNextObject()) ) 
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection,next)) ) 
-            {
-                parent = (IOService *)connection->copyParentEntry(gIOPowerPlane);
-                if ( parent ) {
-                    if ( parent->requestPowerDomainState(ourRequest,connection,IOPMLowestState)!= IOPMNoErr ) 
-                    {
-                        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogRequestDenied,
-                                                                (unsigned long)priv->previousRequest,0);
-                    }
-                    parent->release();
-                }
-            }
-        }
-        iter->release();
-    }
-
-    return IOPMNoErr;
-}
-
-
-//*********************************************************************************
-// instruct_driver
-//
-// Call the controlling driver and have it change the power state of the
-// hardware.  If it returns IOPMAckImplied, the change is complete, and
-// we return IOPMAckImplied.  Otherwise, it will ack when the change
-// is done; we return IOPMWillAckLater.
-//*********************************************************************************
-IOReturn IOService::instruct_driver ( unsigned long newState )
-{
-    IOReturn return_code;
-
-    // can our driver switch to the desired state?
-    if (  pm_vars->thePowerStates[newState].capabilityFlags & IOPMNotAttainable ) 
-    {
-        // no, so don't try
-        return IOPMAckImplied;
-    }
-
-    priv->driver_timer = -1;
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogProgramHardware,newState,0);
-
-    // yes, instruct it
-    ioSPMTraceStart(IOPOWER_STATE, * (int *) this, (int) newState); 
-    return_code = pm_vars->theControllingDriver->setPowerState( newState,this );
-    ioSPMTraceEnd(IOPOWER_STATE, * (int *) this, (int) newState, (int) return_code);
-
-    // it finished
-    if ( return_code == IOPMAckImplied ) 
-    {
-        priv->driver_timer = 0;
-        return IOPMAckImplied;
-    }
+bool
+IOService::actionPMRequestQueue(
+       IOPMRequest *       request,
+       IOPMRequestQueue *  queue )
+{
+       bool more;
 
-    // it acked behind our back
-    if ( priv->driver_timer == 0 ) 
-    {
-        return IOPMAckImplied;
-    }
+       if (initialized) {
+               // Work queue will immediately execute the request if the per-service
+               // request queue is empty. Note pwrMgt is the target's IOServicePM.
 
-    // somebody goofed
-    if ( return_code < 0 ) 
-    {
-        return IOPMAckImplied;
-    }
-    
-    // it didn't finish
-    priv->driver_timer = (return_code / ( ACK_TIMER_PERIOD / ns_per_us )) + 1;
-    return IOPMWillAckLater;
-}
-
-
-//*********************************************************************************
-// acquire_lock
-//
-// We are acquiring the lock we use to protect our queue head from
-// simutaneous access by a thread which calls acknowledgePowerStateChange
-// or acknowledgeSetPowerState and the ack timer expiration thread.
-// Return TRUE if we acquire the lock, and the queue head didn't change
-// while we were acquiring the lock (and maybe blocked).
-// If there is no queue head, or it changes while we are blocked,
-// return FALSE with the lock unlocked.
-//*********************************************************************************
+               more = gIOPMWorkQueue->queuePMRequest(request, pwrMgt);
+       } else {
+               // Calling PM without PMinit() is not allowed, fail the request.
+               // Need to signal more when completing attached requests.
 
-bool IOService::acquire_lock ( void )
-{
-    long current_change_note;
+               PM_LOG("%s: PM not initialized\n", getName());
+               PM_LOG1("[- %02x] %p [%p %s] !initialized\n",
+                   request->getType(), OBFUSCATE(request),
+                   OBFUSCATE(this), getName());
 
-    current_change_note = priv->head_note;
-    if ( current_change_note == -1 ) {
-        return FALSE;
-    }
+               more = gIOPMCompletionQueue->queuePMRequest(request);
+               if (more) {
+                       gIOPMWorkQueue->incrementProducerCount();
+               }
+       }
 
-    IOTakeLock(priv->our_lock);
-    if ( current_change_note == priv->head_note ) 
-    {
-        return TRUE;
-    } else {
-        // we blocked and something changed radically
-        // so there's nothing to do any more
-        IOUnlock(priv->our_lock);
-        return FALSE;
-    }
+       return more;
 }
 
-
 //*********************************************************************************
-// askChangeDown
-//
-// Ask registered applications and kernel clients if we can change to a lower
-// power state.
-//
-// Subclass can override this to send a different message type.  Parameter is
-// the destination state number.
+// [private] actionPMCompletionQueue
 //
-// Return true if we don't have to wait for acknowledgements
+// IOPMCompletionQueue::checkForWork() passing a completed request to the
+// request target.
 //*********************************************************************************
 
-bool IOService::askChangeDown ( unsigned long stateNum )
+bool
+IOService::actionPMCompletionQueue(
+       IOPMRequest *         request,
+       IOPMCompletionQueue * queue )
 {
-    return tellClientsWithResponse(kIOMessageCanDevicePowerOff);
+       bool            more = (request->getNextRequest() != NULL);
+       IOPMRequest *   root = request->getRootRequest();
+
+       if (root && (root != request)) {
+               more = true;
+       }
+       if (more) {
+               gIOPMWorkQueue->incrementProducerCount();
+       }
+
+       releasePMRequest( request );
+       return more;
 }
 
-
 //*********************************************************************************
-// tellChangeDown1
-//
-// Notify registered applications and kernel clients that we are definitely
-// dropping power.
+// [private] actionPMWorkQueueRetire
 //
-// Return true if we don't have to wait for acknowledgements
+// IOPMWorkQueue::checkForWork() passing a retired request to the request target.
 //*********************************************************************************
 
-bool IOService::tellChangeDown1 ( unsigned long stateNum )
+bool
+IOService::actionPMWorkQueueRetire( IOPMRequest * request, IOPMWorkQueue * queue )
 {
-    pm_vars->outofbandparameter = kNotifyApps;
-    return tellChangeDown(stateNum);
+       assert(request && queue);
+
+       PM_LOG1("[- %02x] %p [%p %s] state %d, busy %d\n",
+           request->getType(), OBFUSCATE(request),
+           OBFUSCATE(this), getName(),
+           fMachineState, gIOPMBusyRequestCount);
+
+       // Catch requests created by idleTimerExpired()
+       if (request->getType() == kIOPMRequestTypeActivityTickle) {
+               uint32_t tickleFlags = (uint32_t)(uintptr_t) request->fArg1;
+
+               if ((tickleFlags & kTickleTypePowerDrop) && fIdleTimerPeriod) {
+                       restartIdleTimer();
+               } else if (tickleFlags == (kTickleTypeActivity | kTickleTypePowerRise)) {
+                       // Invalidate any idle power drop that got queued while
+                       // processing this request.
+                       fIdleTimerGeneration++;
+               }
+       }
+
+       // When the completed request is linked, tell work queue there is
+       // more work pending.
+
+       return gIOPMCompletionQueue->queuePMRequest( request );
 }
 
-
 //*********************************************************************************
-// tellChangeDown2
-//
-// Notify priority clients that we are definitely dropping power.
+// [private] isPMBlocked
 //
-// Return true if we don't have to wait for acknowledgements
+// Check if machine state transition is blocked.
 //*********************************************************************************
 
-bool IOService::tellChangeDown2 ( unsigned long stateNum )
+bool
+IOService::isPMBlocked( IOPMRequest * request, int count )
 {
-    pm_vars->outofbandparameter = kNotifyPriority;
-    return tellChangeDown(stateNum);
+       int reason = 0;
+
+       do {
+               if (kIOPM_Finished == fMachineState) {
+                       break;
+               }
+
+               if (kIOPM_DriverThreadCallDone == fMachineState) {
+                       // 5 = kDriverCallInformPreChange
+                       // 6 = kDriverCallInformPostChange
+                       // 7 = kDriverCallSetPowerState
+                       // 8 = kRootDomainInformPreChange
+                       if (fDriverCallBusy) {
+                               reason = 5 + fDriverCallReason;
+                       }
+                       break;
+               }
+
+               // Waiting on driver's setPowerState() timeout.
+               if (fDriverTimer) {
+                       reason = 1; break;
+               }
+
+               // Child or interested driver acks pending.
+               if (fHeadNotePendingAcks) {
+                       reason = 2; break;
+               }
+
+               // Waiting on apps or priority power interest clients.
+               if (fResponseArray) {
+                       reason = 3; break;
+               }
+
+               // Waiting on settle timer expiration.
+               if (fSettleTimeUS) {
+                       reason = 4; break;
+               }
+       } while (false);
+
+       fWaitReason = reason;
+
+       if (reason) {
+               if (count) {
+                       PM_LOG1("[B %02x] %p [%p %s] state %d, reason %d\n",
+                           request->getType(), OBFUSCATE(request),
+                           OBFUSCATE(this), getName(),
+                           fMachineState, reason);
+               }
+
+               return true;
+       }
+
+       return false;
 }
 
-
 //*********************************************************************************
-// tellChangeDown
-//
-// Notify registered applications and kernel clients that we are definitely
-// dropping power.
-//
-// Subclass can override this to send a different message type.  Parameter is
-// the destination state number.
+// [private] actionPMWorkQueueInvoke
 //
-// Return true if we don't have to wait for acknowledgements
+// IOPMWorkQueue::checkForWork() passing a request to the
+// request target for execution.
 //*********************************************************************************
 
-bool IOService::tellChangeDown ( unsigned long stateNum )
+bool
+IOService::actionPMWorkQueueInvoke( IOPMRequest * request, IOPMWorkQueue * queue )
 {
-    return tellClientsWithResponse(kIOMessageDeviceWillPowerOff);
+       bool    done = false;
+       int     loop = 0;
+
+       assert(request && queue);
+
+       while (isPMBlocked(request, loop++) == false) {
+               PM_LOG1("[W %02x] %p [%p %s] state %d\n",
+                   request->getType(), OBFUSCATE(request),
+                   OBFUSCATE(this), getName(), fMachineState);
+
+               gIOPMRequest = request;
+               gIOPMWorkInvokeCount++;
+
+               // Every PM machine states must be handled in one of the cases below.
+
+               switch (fMachineState) {
+               case kIOPM_Finished:
+                       start_watchdog_timer();
+
+                       executePMRequest( request );
+                       break;
+
+               case kIOPM_OurChangeTellClientsPowerDown:
+                       // Root domain might self cancel due to assertions.
+                       if (IS_ROOT_DOMAIN) {
+                               bool cancel = (bool) fDoNotPowerDown;
+                               getPMRootDomain()->askChangeDownDone(
+                                       &fHeadNoteChangeFlags, &cancel);
+                               fDoNotPowerDown = cancel;
+                       }
+
+                       // askChangeDown() done, was it vetoed?
+                       if (!fDoNotPowerDown) {
+                               // no, we can continue
+                               OurChangeTellClientsPowerDown();
+                       } else {
+                               OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
+                               PM_ERROR("%s: idle cancel, state %u\n", fName, fMachineState);
+                               if (IS_ROOT_DOMAIN) {
+                                       // RootDomain already sent "WillSleep" to its clients
+                                       tellChangeUp(fCurrentPowerState);
+                               } else {
+                                       tellNoChangeDown(fHeadNotePowerState);
+                               }
+                               // mark the change note un-actioned
+                               fHeadNoteChangeFlags |= kIOPMNotDone;
+                               // and we're done
+                               OurChangeFinish();
+                       }
+                       break;
+
+               case kIOPM_OurChangeTellUserPMPolicyPowerDown:
+                       // PMRD: tellChangeDown/kNotifyApps done, was it cancelled?
+                       if (fDoNotPowerDown) {
+                               OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
+                               PM_ERROR("%s: idle cancel, state %u\n", fName, fMachineState);
+                               if (IS_ROOT_DOMAIN) {
+                                       // RootDomain already sent "WillSleep" to its clients
+                                       tellChangeUp(fCurrentPowerState);
+                               } else {
+                                       tellNoChangeDown(fHeadNotePowerState);
+                               }
+                               // mark the change note un-actioned
+                               fHeadNoteChangeFlags |= kIOPMNotDone;
+                               // and we're done
+                               OurChangeFinish();
+                       } else {
+                               OurChangeTellUserPMPolicyPowerDown();
+                       }
+                       break;
+
+               case kIOPM_OurChangeTellPriorityClientsPowerDown:
+                       // PMRD:     LastCallBeforeSleep notify done
+                       // Non-PMRD: tellChangeDown/kNotifyApps done
+                       if (fDoNotPowerDown) {
+                               OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
+                               PM_ERROR("%s: idle revert, state %u\n", fName, fMachineState);
+                               // no, tell clients we're back in the old state
+                               tellChangeUp(fCurrentPowerState);
+                               // mark the change note un-actioned
+                               fHeadNoteChangeFlags |= kIOPMNotDone;
+                               // and we're done
+                               OurChangeFinish();
+                       } else {
+                               // yes, we can continue
+                               OurChangeTellPriorityClientsPowerDown();
+                       }
+                       break;
+
+               case kIOPM_OurChangeNotifyInterestedDriversWillChange:
+                       OurChangeNotifyInterestedDriversWillChange();
+                       break;
+
+               case kIOPM_OurChangeSetPowerState:
+                       OurChangeSetPowerState();
+                       break;
+
+               case kIOPM_OurChangeWaitForPowerSettle:
+                       OurChangeWaitForPowerSettle();
+                       break;
+
+               case kIOPM_OurChangeNotifyInterestedDriversDidChange:
+                       OurChangeNotifyInterestedDriversDidChange();
+                       break;
+
+               case kIOPM_OurChangeTellCapabilityDidChange:
+                       OurChangeTellCapabilityDidChange();
+                       break;
+
+               case kIOPM_OurChangeFinish:
+                       OurChangeFinish();
+                       break;
+
+               case kIOPM_ParentChangeTellPriorityClientsPowerDown:
+                       ParentChangeTellPriorityClientsPowerDown();
+                       break;
+
+               case kIOPM_ParentChangeNotifyInterestedDriversWillChange:
+                       ParentChangeNotifyInterestedDriversWillChange();
+                       break;
+
+               case kIOPM_ParentChangeSetPowerState:
+                       ParentChangeSetPowerState();
+                       break;
+
+               case kIOPM_ParentChangeWaitForPowerSettle:
+                       ParentChangeWaitForPowerSettle();
+                       break;
+
+               case kIOPM_ParentChangeNotifyInterestedDriversDidChange:
+                       ParentChangeNotifyInterestedDriversDidChange();
+                       break;
+
+               case kIOPM_ParentChangeTellCapabilityDidChange:
+                       ParentChangeTellCapabilityDidChange();
+                       break;
+
+               case kIOPM_ParentChangeAcknowledgePowerChange:
+                       ParentChangeAcknowledgePowerChange();
+                       break;
+
+               case kIOPM_DriverThreadCallDone:
+                       switch (fDriverCallReason) {
+                       case kDriverCallInformPreChange:
+                       case kDriverCallInformPostChange:
+                               notifyInterestedDriversDone();
+                               break;
+                       case kDriverCallSetPowerState:
+                               notifyControllingDriverDone();
+                               break;
+                       case kRootDomainInformPreChange:
+                               notifyRootDomainDone();
+                               break;
+                       default:
+                               panic("%s: bad call reason %x",
+                                   getName(), fDriverCallReason);
+                       }
+                       break;
+
+               case kIOPM_NotifyChildrenOrdered:
+                       notifyChildrenOrdered();
+                       break;
+
+               case kIOPM_NotifyChildrenDelayed:
+                       notifyChildrenDelayed();
+                       break;
+
+               case kIOPM_NotifyChildrenStart:
+                       // pop notifyAll() state saved by notifyInterestedDriversDone()
+                       MS_POP();
+                       notifyRootDomain();
+                       break;
+
+               case kIOPM_SyncTellClientsPowerDown:
+                       // Root domain might self cancel due to assertions.
+                       if (IS_ROOT_DOMAIN) {
+                               bool cancel = (bool) fDoNotPowerDown;
+                               getPMRootDomain()->askChangeDownDone(
+                                       &fHeadNoteChangeFlags, &cancel);
+                               fDoNotPowerDown = cancel;
+                       }
+                       if (!fDoNotPowerDown) {
+                               fMachineState = kIOPM_SyncTellPriorityClientsPowerDown;
+                               fOutOfBandParameter = kNotifyApps;
+                               tellChangeDown(fHeadNotePowerState);
+                       } else {
+                               // Cancelled by IOPMrootDomain::askChangeDownDone() or
+                               // askChangeDown/kNotifyApps
+                               OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
+                               PM_ERROR("%s: idle cancel, state %u\n", fName, fMachineState);
+                               tellNoChangeDown(fHeadNotePowerState);
+                               fHeadNoteChangeFlags |= kIOPMNotDone;
+                               OurChangeFinish();
+                       }
+                       break;
+
+               case kIOPM_SyncTellPriorityClientsPowerDown:
+                       // PMRD: tellChangeDown/kNotifyApps done, was it cancelled?
+                       if (!fDoNotPowerDown) {
+                               fMachineState = kIOPM_SyncNotifyWillChange;
+                               fOutOfBandParameter = kNotifyPriority;
+                               tellChangeDown(fHeadNotePowerState);
+                       } else {
+                               OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
+                               PM_ERROR("%s: idle revert, state %u\n", fName, fMachineState);
+                               tellChangeUp(fCurrentPowerState);
+                               fHeadNoteChangeFlags |= kIOPMNotDone;
+                               OurChangeFinish();
+                       }
+                       break;
+
+               case kIOPM_SyncNotifyWillChange:
+                       if (kIOPMSyncNoChildNotify & fHeadNoteChangeFlags) {
+                               fMachineState = kIOPM_SyncFinish;
+                               continue;
+                       }
+                       fMachineState     = kIOPM_SyncNotifyDidChange;
+                       fDriverCallReason = kDriverCallInformPreChange;
+                       notifyChildren();
+                       break;
+
+               case kIOPM_SyncNotifyDidChange:
+                       fIsPreChange = false;
+
+                       if (fHeadNoteChangeFlags & kIOPMParentInitiated) {
+                               fMachineState = kIOPM_SyncFinish;
+                       } else {
+                               assert(IS_ROOT_DOMAIN);
+                               fMachineState = kIOPM_SyncTellCapabilityDidChange;
+                       }
+
+                       fDriverCallReason = kDriverCallInformPostChange;
+                       notifyChildren();
+                       break;
+
+               case kIOPM_SyncTellCapabilityDidChange:
+                       tellSystemCapabilityChange( kIOPM_SyncFinish );
+                       break;
+
+               case kIOPM_SyncFinish:
+                       if (fHeadNoteChangeFlags & kIOPMParentInitiated) {
+                               ParentChangeAcknowledgePowerChange();
+                       } else {
+                               OurChangeFinish();
+                       }
+                       break;
+
+               case kIOPM_TellCapabilityChangeDone:
+                       if (fIsPreChange) {
+                               if (fOutOfBandParameter == kNotifyCapabilityChangePriority) {
+                                       MS_POP(); // tellSystemCapabilityChange()
+                                       continue;
+                               }
+                               fOutOfBandParameter = kNotifyCapabilityChangePriority;
+                       } else {
+                               if (fOutOfBandParameter == kNotifyCapabilityChangeApps) {
+                                       MS_POP(); // tellSystemCapabilityChange()
+                                       continue;
+                               }
+                               fOutOfBandParameter = kNotifyCapabilityChangeApps;
+                       }
+                       tellClientsWithResponse( fOutOfBandMessage );
+                       break;
+
+               default:
+                       panic("PMWorkQueueInvoke: unknown machine state %x",
+                           fMachineState);
+               }
+
+               gIOPMRequest = NULL;
+
+               if (fMachineState == kIOPM_Finished) {
+                       stop_watchdog_timer();
+                       done = true;
+                       break;
+               }
+       }
+
+       return done;
 }
 
-
-//*********************************************************************************
-// tellClientsWithResponse
-//
-// Notify registered applications and kernel clients that we are definitely
-// dropping power.
-//
-// Return true if we don't have to wait for acknowledgements
-//*********************************************************************************
-
-bool IOService::tellClientsWithResponse ( int messageType )
-{
-    struct context                          theContext;
-    AbsoluteTime                            deadline;
-    OSBoolean                               *aBool;
-
-    pm_vars->responseFlags = OSArray::withCapacity( 1 );
-    pm_vars->serialNumber += 1;
-    
-    theContext.responseFlags = pm_vars->responseFlags;
-    theContext.serialNumber = pm_vars->serialNumber;
-    theContext.flags_lock = priv->flags_lock;
-    theContext.counter = 1;
-    theContext.msgType = messageType;
-    theContext.us = this;
-    theContext.maxTimeRequested = 0;
-    theContext.stateNumber = priv->head_note_state;
-    theContext.stateFlags = priv->head_note_capabilityFlags;
-
-    IOLockLock(priv->flags_lock);
-
-    // position zero is false to
-    // prevent allowCancelCommon from succeeding
-    aBool = OSBoolean::withBoolean(false);
-    theContext.responseFlags->setObject(0,aBool);
-    aBool->release();
-    IOLockUnlock(priv->flags_lock);
-
-    switch ( pm_vars->outofbandparameter ) {
-        case kNotifyApps:
-            applyToInterested(gIOAppPowerStateInterest,tellAppWithResponse,(void *)&theContext);
-            applyToInterested(gIOGeneralInterest,tellClientWithResponse,(void *)&theContext);
-            break;
-        case kNotifyPriority:
-            applyToInterested(gIOPriorityPowerStateInterest,tellClientWithResponse,(void *)&theContext);
-            break;
-    }
-
-    if (! acquire_lock() ) 
-    {
-        return true;
-    }
-    IOLockLock(priv->flags_lock);
-    // now fix position zero
-    aBool = OSBoolean::withBoolean(true);
-    theContext.responseFlags->replaceObject(0,aBool);
-    aBool->release();
-    IOLockUnlock(priv->flags_lock);
-    
-    // do we have to wait for somebody?
-    if ( ! checkForDone() ) 
-    {
-        // yes, start the ackTimer
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogStartAckTimer,theContext.maxTimeRequested,0);
-        clock_interval_to_deadline(theContext.maxTimeRequested / 1000, kMillisecondScale, &deadline);
-        
-        thread_call_enter_delayed(priv->ackTimer, deadline);
-    
-        IOUnlock(priv->our_lock);                      
-        return false;
-    }
-    
-    IOUnlock(priv->our_lock);
-    IOLockLock(priv->flags_lock);
-    
-    // everybody responded
-    pm_vars->responseFlags->release();
-    pm_vars->responseFlags = NULL;
-    IOLockUnlock(priv->flags_lock);
-    
-    return true;
-}
-
-
-//*********************************************************************************
-// tellAppWithResponse
-//
-// We send a message to an application, and we expect a response, so we compute a
-// cookie we can identify the response with.
 //*********************************************************************************
-void tellAppWithResponse ( OSObject * object, void * context)
-{
-    struct context                      *theContext = (struct context *)context;
-    UInt32                              refcon;
-    OSBoolean                           *aBool;
-    
-    if( OSDynamicCast( IOService, object) ) 
-    {
-        IOLockLock(theContext->flags_lock);
-        aBool = OSBoolean::withBoolean(true);
-        theContext->responseFlags->setObject(theContext->counter,aBool);
-        aBool->release();
-        IOLockUnlock(theContext->flags_lock);
-    } else {
-        refcon = ((theContext->serialNumber & 0xFFFF)<<16) + (theContext->counter & 0xFFFF);
-        IOLockLock(theContext->flags_lock);
-        aBool = OSBoolean::withBoolean(false);
-        theContext->responseFlags->setObject(theContext->counter,aBool);
-        aBool->release();
-        IOLockUnlock(theContext->flags_lock);
-        theContext->us->messageClient(theContext->msgType,object,(void *)refcon);
-        if ( theContext->maxTimeRequested < k30seconds ) 
-        {
-            theContext->maxTimeRequested = k30seconds;
-        }
-    }
-    theContext->counter += 1;
-}
-
-
-//*********************************************************************************
-// tellClientWithResponse
-//
-// We send a message to an in-kernel client, and we expect a response, so we compute a
-// cookie we can identify the response with.
-// If it doesn't understand the notification (it is not power-management savvy)
-// we won't wait for it to prepare for sleep.  If it tells us via a return code
-// in the passed struct that it is currently ready, we won't wait for it to prepare.
-// If it tells us via the return code in the struct that it does need time, we will chill.
-//*********************************************************************************
-void tellClientWithResponse ( OSObject * object, void * context)
-{
-    struct context                          *theContext = (struct context *)context;
-    IOPowerStateChangeNotification          notify;
-    UInt32                                  refcon;
-    IOReturn                                retCode;
-    OSBoolean                               *aBool;
-    OSObject                                *theFlag;
-    
-    refcon = ((theContext->serialNumber & 0xFFFF)<<16) + (theContext->counter & 0xFFFF);
-    IOLockLock(theContext->flags_lock);
-    aBool = OSBoolean::withBoolean(false);
-    theContext->responseFlags->setObject(theContext->counter,aBool);
-    aBool->release();
-    IOLockUnlock(theContext->flags_lock);
-
-    notify.powerRef = (void *)refcon;
-    notify.returnValue = 0;
-    notify.stateNumber = theContext->stateNumber;
-    notify.stateFlags = theContext->stateFlags;
-    retCode = theContext->us->messageClient(theContext->msgType,object,(void *)&notify);
-    if ( retCode == kIOReturnSuccess ) 
-    {
-        if ( notify.returnValue == 0 ) 
-        {
-            // client doesn't want time to respond
-            IOLockLock(theContext->flags_lock);
-            aBool = OSBoolean::withBoolean(true);
-            // so set its flag true
-            theContext->responseFlags->replaceObject(theContext->counter,aBool);
-            aBool->release();
-            IOLockUnlock(theContext->flags_lock);
-        } else {
-            IOLockLock(theContext->flags_lock);
-            
-            // it does want time, and it hasn't responded yet
-            theFlag = theContext->responseFlags->getObject(theContext->counter);
-            if ( theFlag != 0 ) 
-            {
-                if ( ((OSBoolean *)theFlag)->isFalse() ) 
-                {
-                    // so note its time requirement
-                    if ( theContext->maxTimeRequested < notify.returnValue ) 
-                    {
-                        theContext->maxTimeRequested = notify.returnValue;
-                    }
-                }
-            }
-            IOLockUnlock(theContext->flags_lock);
-        }
-    } else {
-        // not a client of ours
-        IOLockLock(theContext->flags_lock);
-        // so we won't be waiting for response
-        aBool = OSBoolean::withBoolean(true);
-        theContext->responseFlags->replaceObject(theContext->counter,aBool);
-        aBool->release();
-        IOLockUnlock(theContext->flags_lock);
-    }
-    theContext->counter += 1;
-}
-
-
-//*********************************************************************************
-// tellNoChangeDown
-//
-// Notify registered applications and kernel clients that we are not
-// dropping power.
-//
-// Subclass can override this to send a different message type.  Parameter is
-// the aborted destination state number.
+// [private] executePMRequest
 //*********************************************************************************
 
-void IOService::tellNoChangeDown ( unsigned long )
+void
+IOService::executePMRequest( IOPMRequest * request )
 {
-    return tellClients(kIOMessageDeviceWillNotPowerOff);
+       assert( kIOPM_Finished == fMachineState );
+
+       switch (request->getType()) {
+       case kIOPMRequestTypePMStop:
+               handlePMstop( request );
+               break;
+
+       case kIOPMRequestTypeAddPowerChild1:
+               addPowerChild1( request );
+               break;
+
+       case kIOPMRequestTypeAddPowerChild2:
+               addPowerChild2( request );
+               break;
+
+       case kIOPMRequestTypeAddPowerChild3:
+               addPowerChild3( request );
+               break;
+
+       case kIOPMRequestTypeRegisterPowerDriver:
+               handleRegisterPowerDriver( request );
+               break;
+
+       case kIOPMRequestTypeAdjustPowerState:
+               fAdjustPowerScheduled = false;
+               adjustPowerState();
+               break;
+
+       case kIOPMRequestTypePowerDomainWillChange:
+               handlePowerDomainWillChangeTo( request );
+               break;
+
+       case kIOPMRequestTypePowerDomainDidChange:
+               handlePowerDomainDidChangeTo( request );
+               break;
+
+       case kIOPMRequestTypeRequestPowerState:
+       case kIOPMRequestTypeRequestPowerStateOverride:
+               handleRequestPowerState( request );
+               break;
+
+       case kIOPMRequestTypePowerOverrideOnPriv:
+       case kIOPMRequestTypePowerOverrideOffPriv:
+               handlePowerOverrideChanged( request );
+               break;
+
+       case kIOPMRequestTypeActivityTickle:
+               handleActivityTickle( request );
+               break;
+
+       case kIOPMRequestTypeSynchronizePowerTree:
+               handleSynchronizePowerTree( request );
+               break;
+
+       case kIOPMRequestTypeSetIdleTimerPeriod:
+       {
+               fIdleTimerPeriod = (uintptr_t) request->fArg0;
+               fNextIdleTimerPeriod = fIdleTimerPeriod;
+               if ((false == fLockedFlags.PMStop) && (fIdleTimerPeriod > 0)) {
+                       restartIdleTimer();
+               }
+       }
+       break;
+
+       case kIOPMRequestTypeIgnoreIdleTimer:
+               fIdleTimerIgnored = request->fArg0 ? 1 : 0;
+               break;
+
+       case kIOPMRequestTypeQuiescePowerTree:
+               gIOPMWorkQueue->finishQuiesceRequest(request);
+               break;
+
+       default:
+               panic("executePMRequest: unknown request type %x", request->getType());
+       }
 }
 
-
 //*********************************************************************************
-// tellChangeUp
-//
-// Notify registered applications and kernel clients that we are raising power.
+// [private] actionPMReplyQueue
 //
-// Subclass can override this to send a different message type.  Parameter is
-// the aborted destination state number.
+// IOPMRequestQueue::checkForWork() passing a reply-type request to the
+// request target.
 //*********************************************************************************
 
-void IOService::tellChangeUp ( unsigned long )
+bool
+IOService::actionPMReplyQueue( IOPMRequest * request, IOPMRequestQueue * queue )
 {
-    return tellClients(kIOMessageDeviceHasPoweredOn);
+       bool more = false;
+
+       assert( request && queue );
+       assert( request->isReplyType());
+
+       PM_LOG1("[A %02x] %p [%p %s] state %d\n",
+           request->getType(), OBFUSCATE(request),
+           OBFUSCATE(this), getName(), fMachineState);
+
+       switch (request->getType()) {
+       case kIOPMRequestTypeAllowPowerChange:
+       case kIOPMRequestTypeCancelPowerChange:
+               // Check if we are expecting this response.
+               if (responseValid((uint32_t)(uintptr_t) request->fArg0,
+                   (int)(uintptr_t) request->fArg1)) {
+                       if (kIOPMRequestTypeCancelPowerChange == request->getType()) {
+                               // Clients are not allowed to cancel when kIOPMSkipAskPowerDown
+                               // flag is set. Only root domain will set this flag.
+                               // However, there is one exception to this rule. User-space PM
+                               // policy may choose to cancel sleep even after all clients have
+                               // been notified that we will lower power.
+
+                               if ((fMachineState == kIOPM_OurChangeTellUserPMPolicyPowerDown)
+                                   || (fMachineState == kIOPM_OurChangeTellPriorityClientsPowerDown)
+                                   || ((fHeadNoteChangeFlags & kIOPMSkipAskPowerDown) == 0)) {
+                                       fDoNotPowerDown = true;
+
+                                       OSString * name = (OSString *) request->fArg2;
+                                       getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                               gIOPMStatsResponseCancel,
+                                               name ? name->getCStringNoCopy() : "", 0,
+                                               0, (int)(uintptr_t) request->fArg1, NULL);
+                               }
+                       }
+
+                       if (checkForDone()) {
+                               stop_ack_timer();
+                               cleanClientResponses(false);
+                               more = true;
+                       }
+               }
+               // OSString containing app name in Arg2 must be released.
+               if (request->getType() == kIOPMRequestTypeCancelPowerChange) {
+                       OSObject * obj = (OSObject *) request->fArg2;
+                       if (obj) {
+                               obj->release();
+                       }
+               }
+               break;
+
+       case kIOPMRequestTypeAckPowerChange:
+               more = handleAcknowledgePowerChange( request );
+               break;
+
+       case kIOPMRequestTypeAckSetPowerState:
+               if (fDriverTimer == -1) {
+                       // driver acked while setPowerState() call is in-flight.
+                       // take this ack, return value from setPowerState() is irrelevant.
+                       OUR_PMLog(kPMLogDriverAcknowledgeSet,
+                           (uintptr_t) this, fDriverTimer);
+                       fDriverTimer = 0;
+               } else if (fDriverTimer > 0) {
+                       // expected ack, stop the timer
+                       stop_ack_timer();
+
+                       getPMRootDomain()->reset_watchdog_timer(this, 0);
+
+                       uint64_t nsec = computeTimeDeltaNS(&fDriverCallStartTime);
+                       if (nsec > LOG_SETPOWER_TIMES) {
+                               getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                       gIOPMStatsDriverPSChangeSlow,
+                                       fName, kDriverCallSetPowerState, NS_TO_MS(nsec), getRegistryEntryID(),
+                                       NULL, fHeadNotePowerState);
+                       }
+
+                       OUR_PMLog(kPMLogDriverAcknowledgeSet, (uintptr_t) this, fDriverTimer);
+                       fDriverTimer = 0;
+                       more = true;
+               } else {
+                       // unexpected ack
+                       OUR_PMLog(kPMLogAcknowledgeErr4, (uintptr_t) this, 0);
+               }
+               break;
+
+       case kIOPMRequestTypeInterestChanged:
+               handleInterestChanged( request );
+               more = true;
+               break;
+
+       case kIOPMRequestTypeIdleCancel:
+               if ((fMachineState == kIOPM_OurChangeTellClientsPowerDown)
+                   || (fMachineState == kIOPM_OurChangeTellUserPMPolicyPowerDown)
+                   || (fMachineState == kIOPM_OurChangeTellPriorityClientsPowerDown)
+                   || (fMachineState == kIOPM_SyncTellClientsPowerDown)
+                   || (fMachineState == kIOPM_SyncTellPriorityClientsPowerDown)) {
+                       OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
+                       PM_LOG2("%s: cancel from machine state %d\n",
+                           getName(), fMachineState);
+                       fDoNotPowerDown = true;
+                       // Stop waiting for app replys.
+                       if ((fMachineState == kIOPM_OurChangeTellPriorityClientsPowerDown) ||
+                           (fMachineState == kIOPM_OurChangeTellUserPMPolicyPowerDown) ||
+                           (fMachineState == kIOPM_SyncTellPriorityClientsPowerDown) ||
+                           (fMachineState == kIOPM_SyncTellClientsPowerDown)) {
+                               cleanClientResponses(false);
+                       }
+                       more = true;
+               }
+               break;
+
+       case kIOPMRequestTypeChildNotifyDelayCancel:
+               if (fMachineState == kIOPM_NotifyChildrenDelayed) {
+                       PM_LOG2("%s: delay notify cancelled\n", getName());
+                       notifyChildrenDelayed();
+               }
+               break;
+
+       default:
+               panic("PMReplyQueue: unknown reply type %x", request->getType());
+       }
+
+       more |= gIOPMCompletionQueue->queuePMRequest(request);
+       if (more) {
+               gIOPMWorkQueue->incrementProducerCount();
+       }
+
+       return more;
 }
 
-
 //*********************************************************************************
-// tellClients
-//
-// Notify registered applications and kernel clients of something.
+// [private] assertPMDriverCall / deassertPMDriverCall
 //*********************************************************************************
 
-void IOService::tellClients ( int messageType )
-{
-    struct context theContext;
-
-    theContext.msgType = messageType;
-    theContext.us = this;
-    theContext.stateNumber = priv->head_note_state;
-    theContext.stateFlags = priv->head_note_capabilityFlags;
-
-    applyToInterested(gIOAppPowerStateInterest,tellClient,(void *)&theContext);
-    applyToInterested(gIOGeneralInterest,tellClient,(void *)&theContext);
-}
-
-
-//*********************************************************************************
-// tellClient
-//
-// Notify a registered application or kernel client of something.
-//*********************************************************************************
-void tellClient ( OSObject * object, void * context)
+bool
+IOService::assertPMDriverCall(
+       IOPMDriverCallEntry *   entry,
+       IOOptionBits            method,
+       const IOPMinformee *    inform,
+       IOOptionBits            options )
 {
-    struct context                              *theContext = (struct context *)context;
-    IOPowerStateChangeNotification              notify;
-
-    notify.powerRef    = (void *) 0;
-    notify.returnValue = 0;
-    notify.stateNumber = theContext->stateNumber;
-    notify.stateFlags  = theContext->stateFlags;
-
-    theContext->us->messageClient(theContext->msgType,object, &notify);
+       IOService * target = NULL;
+       bool        ok = false;
+
+       if (!initialized) {
+               return false;
+       }
+
+       PM_LOCK();
+
+       if (fLockedFlags.PMStop) {
+               goto fail;
+       }
+
+       if (((options & kIOPMDriverCallNoInactiveCheck) == 0) && isInactive()) {
+               goto fail;
+       }
+
+       if (inform) {
+               if (!inform->active) {
+                       goto fail;
+               }
+               target = inform->whatObject;
+               if (target->isInactive()) {
+                       goto fail;
+               }
+       }
+
+       // Record calling address for sleep failure diagnostics
+       switch (method) {
+       case kIOPMDriverCallMethodSetPowerState:
+               entry->callMethod = OSMemberFunctionCast(const void *, fControllingDriver, &IOService::setPowerState);
+               break;
+       case kIOPMDriverCallMethodWillChange:
+               entry->callMethod = OSMemberFunctionCast(const void *, target, &IOService::powerStateWillChangeTo);
+               break;
+       case kIOPMDriverCallMethodDidChange:
+               entry->callMethod = OSMemberFunctionCast(const void *, target, &IOService::powerStateDidChangeTo);
+               break;
+       case kIOPMDriverCallMethodUnknown:
+       case kIOPMDriverCallMethodSetAggressive:
+       default:
+               entry->callMethod = NULL;
+               break;
+       }
+
+       entry->thread = current_thread();
+       entry->target = target;
+       queue_enter(&fPMDriverCallQueue, entry, IOPMDriverCallEntry *, link);
+       ok = true;
+
+fail:
+       PM_UNLOCK();
+
+       return ok;
 }
 
-
-// **********************************************************************************
-// checkForDone
-//
-// **********************************************************************************
-bool IOService::checkForDone ( void )
+void
+IOService::deassertPMDriverCall( IOPMDriverCallEntry * entry )
 {
-    int                                         i = 0;
-    OSObject                                    *theFlag;
+       bool wakeup = false;
 
-    IOLockLock(priv->flags_lock);
-    if ( pm_vars->responseFlags == NULL ) 
-    {
-        IOLockUnlock(priv->flags_lock);
-        return true;
-    }
-    
-    for ( i = 0; ; i++ ) 
-    {
-        theFlag = pm_vars->responseFlags->getObject(i);
-        if ( theFlag == NULL ) 
-        {
-            break;
-        }
-        if ( ((OSBoolean *)theFlag)->isFalse() ) 
-        {
-            IOLockUnlock(priv->flags_lock);
-            return false;
-        }
-    }
-    IOLockUnlock(priv->flags_lock);
-    return true;
-}
+       PM_LOCK();
 
+       assert( !queue_empty(&fPMDriverCallQueue));
+       queue_remove(&fPMDriverCallQueue, entry, IOPMDriverCallEntry *, link);
+       if (fLockedFlags.PMDriverCallWait) {
+               wakeup = true;
+       }
 
-// **********************************************************************************
-// responseValid
-//
-// **********************************************************************************
-bool IOService::responseValid ( unsigned long x )
-{
-    UInt16 serialComponent;
-    UInt16 ordinalComponent;
-    OSObject * theFlag;
-    unsigned long refcon = (unsigned long)x;
-    OSBoolean * aBool;
-    
-    serialComponent = (refcon>>16) & 0xFFFF;
-    ordinalComponent = refcon & 0xFFFF;
-    
-    if ( serialComponent != pm_vars->serialNumber ) 
-    {
-        return false;
-    }
-    
-    IOLockLock(priv->flags_lock);
-    if ( pm_vars->responseFlags == NULL ) 
-    {
-        IOLockUnlock(priv->flags_lock);
-        return false;
-    }
-    
-    theFlag = pm_vars->responseFlags->getObject(ordinalComponent);
-    
-    if ( theFlag == 0 ) 
-    {
-        IOLockUnlock(priv->flags_lock);
-        return false;
-    }
-    
-    if ( ((OSBoolean *)theFlag)->isFalse() ) 
-    {
-        aBool = OSBoolean::withBoolean(true);
-        pm_vars->responseFlags->replaceObject(ordinalComponent,aBool);
-        aBool->release();
-    }
-    
-    IOLockUnlock(priv->flags_lock);
-    return true;
-}
-
-
-// **********************************************************************************
-// allowPowerChange
-//
-// Our power state is about to lower, and we have notified applications
-// and kernel clients, and one of them has acknowledged.  If this is the last to do
-// so, and all acknowledgements are positive, we continue with the power change.
-//
-// We serialize this processing with timer expiration with a command gate on the
-// power management workloop, which the timer expiration is command gated to as well.
-// **********************************************************************************
-IOReturn IOService::allowPowerChange ( unsigned long refcon )
-{
-    if ( ! initialized ) 
-    {
-        // we're unloading
-        return kIOReturnSuccess;
-    }
+       PM_UNLOCK();
 
-    return pm_vars->PMcommandGate->runAction(serializedAllowPowerChange,(void *)refcon);
+       if (wakeup) {
+               PM_LOCK_WAKEUP(&fPMDriverCallQueue);
+       }
 }
-    
-    
-IOReturn serializedAllowPowerChange ( OSObject *owner, void * refcon, void *, void *, void *)
+
+bool
+IOService::getBlockingDriverCall(thread_t *thread, const void **callMethod)
 {
-    return ((IOService *)owner)->serializedAllowPowerChange2((unsigned long)refcon);
+       const IOPMDriverCallEntry * entry = NULL;
+       bool    blocked = false;
+
+       if (!initialized) {
+               return false;
+       }
+
+       if (current_thread() != gIOPMWatchDogThread) {
+               // Meant to be accessed only from watchdog thread
+               return false;
+       }
+
+       PM_LOCK();
+       entry = qe_queue_first(&fPMDriverCallQueue, IOPMDriverCallEntry, link);
+       if (entry) {
+               *thread = entry->thread;
+               *callMethod = entry->callMethod;
+               blocked = true;
+       }
+       PM_UNLOCK();
+
+       return blocked;
 }
 
-IOReturn IOService::serializedAllowPowerChange2 ( unsigned long refcon )
-{
-    // response valid?
-    if ( ! responseValid(refcon) ) 
-    {
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAcknowledgeErr5,refcon,0);
-        // no, just return
-        return kIOReturnSuccess;
-    }
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientAcknowledge,refcon,0);
 
-    return allowCancelCommon();
+void
+IOService::waitForPMDriverCall( IOService * target )
+{
+       const IOPMDriverCallEntry * entry;
+       thread_t                    thread = current_thread();
+       AbsoluteTime                deadline;
+       int                         waitResult;
+       bool                        log = true;
+       bool                        wait;
+
+       do {
+               wait = false;
+               queue_iterate(&fPMDriverCallQueue, entry, const IOPMDriverCallEntry *, link)
+               {
+                       // Target of interested driver call
+                       if (target && (target != entry->target)) {
+                               continue;
+                       }
+
+                       if (entry->thread == thread) {
+                               if (log) {
+                                       PM_LOG("%s: %s(%s) on PM thread\n",
+                                           fName, __FUNCTION__, target ? target->getName() : "");
+                                       OSReportWithBacktrace("%s: %s(%s) on PM thread\n",
+                                           fName, __FUNCTION__, target ? target->getName() : "");
+                                       log = false;
+                               }
+                               continue;
+                       }
+
+                       wait = true;
+                       break;
+               }
+
+               if (wait) {
+                       fLockedFlags.PMDriverCallWait = true;
+                       clock_interval_to_deadline(15, kSecondScale, &deadline);
+                       waitResult = PM_LOCK_SLEEP(&fPMDriverCallQueue, deadline);
+                       fLockedFlags.PMDriverCallWait = false;
+                       if (THREAD_TIMED_OUT == waitResult) {
+                               PM_ERROR("%s: waitForPMDriverCall timeout\n", fName);
+                               wait = false;
+                       }
+               }
+       } while (wait);
 }
 
+//*********************************************************************************
+// [private] Debug helpers
+//*********************************************************************************
 
-// **********************************************************************************
-// cancelPowerChange
-//
-// Our power state is about to lower, and we have notified applications
-// and kernel clients, and one of them has vetoed the change.  If this is the last
-// client to respond, we abandon the power change.
-//
-// We serialize this processing with timer expiration with a command gate on the
-// power management workloop, which the timer expiration is command gated to as well.
-// **********************************************************************************
-IOReturn IOService::cancelPowerChange ( unsigned long refcon )
-{
-    if ( ! initialized ) 
-    {
-        // we're unloading
-        return kIOReturnSuccess;
-    }
-
-    return pm_vars->PMcommandGate->runAction(serializedCancelPowerChange,(void *)refcon);
-}
-    
-    
-IOReturn serializedCancelPowerChange ( OSObject *owner, void * refcon, void *, void *, void *)
-{
-    return ((IOService *)owner)->serializedCancelPowerChange2((unsigned long)refcon);
-}
-
-IOReturn IOService::serializedCancelPowerChange2 ( unsigned long refcon )
-{
-    // response valid?
-    if ( ! responseValid(refcon) ) 
-    {
-        pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogAcknowledgeErr5,refcon,0);
-        // no, just return
-        return kIOReturnSuccess;
-    }
-    pm_vars->thePlatform->PMLog(pm_vars->ourName,PMlogClientCancel,refcon,0);
-    
-    pm_vars->doNotPowerDown = true;
-
-    return allowCancelCommon();
-}
-
-
-// **********************************************************************************
-// allowCancelCommon
-//
-// **********************************************************************************
-IOReturn IOService::allowCancelCommon ( void )
-{
-    if (! acquire_lock() ) 
-    {
-        return kIOReturnSuccess;
-    }
-
-    // is this the last response?
-    if ( checkForDone() ) 
-    {
-        // yes, stop the timer
-        stop_ack_timer();
-        IOUnlock(priv->our_lock);
-        IOLockLock(priv->flags_lock);
-        if ( pm_vars->responseFlags ) 
-        {
-            pm_vars->responseFlags->release();
-            pm_vars->responseFlags = NULL;
-        }
-        IOLockUnlock(priv->flags_lock);
-        switch (priv->machine_state) {
-            case kIOPM_OurChangeTellClientsPowerDown:
-                // our change, was it vetoed?
-                if ( ! pm_vars->doNotPowerDown ) 
-                {
-                    // no, we can continue
-                    OurChangeTellClientsPowerDown();
-                } else {
-                    // yes, rescind the warning
-                    tellNoChangeDown(priv->head_note_state);
-                    // mark the change note un-actioned
-                    priv->head_note_flags |= IOPMNotDone;
-
-                    // and we're done
-                    all_done();
-                }
-                break;
-            case kIOPM_OurChangeTellPriorityClientsPowerDown:
-                OurChangeTellPriorityClientsPowerDown();  
-                break;
-            case kIOPM_OurChangeNotifyInterestedDriversWillChange:
-                // our change, continue
-                OurChangeNotifyInterestedDriversWillChange();
-                break;
-            case kIOPM_ParentDownTellPriorityClientsPowerDown_Immediate:
-                // parent change, continue
-                ParentDownTellPriorityClientsPowerDown_Delayed();
-                break;
-            case kIOPM_ParentDownNotifyInterestedDriversWillChange_Delayed:
-                // parent change, continue
-                ParentDownNotifyInterestedDriversWillChange_Delayed();
-                break;
-        }
-    } else {
-        // not done yet
-        IOUnlock(priv->our_lock);
-    }
-
-    return kIOReturnSuccess;
+const char *
+IOService::getIOMessageString( uint32_t msg )
+{
+#define MSG_ENTRY(x)    {(int) x, #x}
+
+       static const IONamedValue msgNames[] = {
+               MSG_ENTRY( kIOMessageCanDevicePowerOff      ),
+               MSG_ENTRY( kIOMessageDeviceWillPowerOff     ),
+               MSG_ENTRY( kIOMessageDeviceWillNotPowerOff  ),
+               MSG_ENTRY( kIOMessageDeviceHasPoweredOn     ),
+               MSG_ENTRY( kIOMessageCanSystemPowerOff      ),
+               MSG_ENTRY( kIOMessageSystemWillPowerOff     ),
+               MSG_ENTRY( kIOMessageSystemWillNotPowerOff  ),
+               MSG_ENTRY( kIOMessageCanSystemSleep         ),
+               MSG_ENTRY( kIOMessageSystemWillSleep        ),
+               MSG_ENTRY( kIOMessageSystemWillNotSleep     ),
+               MSG_ENTRY( kIOMessageSystemHasPoweredOn     ),
+               MSG_ENTRY( kIOMessageSystemWillRestart      ),
+               MSG_ENTRY( kIOMessageSystemWillPowerOn      ),
+               MSG_ENTRY( kIOMessageSystemCapabilityChange ),
+               MSG_ENTRY( kIOPMMessageLastCallBeforeSleep  ),
+               MSG_ENTRY( kIOMessageSystemPagingOff        ),
+               { 0, NULL }
+       };
+
+       return IOFindNameForValue(msg, msgNames);
 }
 
 
+// MARK: -
+// MARK: IOPMRequest
+
 //*********************************************************************************
-// clampPowerOn
+// IOPMRequest Class
 //
-// Set to highest available power state for a minimum of duration milliseconds
+// Requests from PM clients, and also used for inter-object messaging within PM.
 //*********************************************************************************
 
-#define kFiveMinutesInNanoSeconds (300 * NSEC_PER_SEC)
+OSDefineMetaClassAndStructors( IOPMRequest, IOCommand );
 
-void IOService::clampPowerOn (unsigned long duration)
+IOPMRequest *
+IOPMRequest::create( void )
 {
-/*
-  changePowerStateToPriv (pm_vars->theNumberOfPowerStates-1);
+       IOPMRequest * me = OSTypeAlloc(IOPMRequest);
+       if (me && !me->init(NULL, kIOPMRequestTypeInvalid)) {
+               me->release();
+               me = NULL;
+       }
+       return me;
+}
 
-  if (  priv->clampTimerEventSrc == NULL ) {
-    priv->clampTimerEventSrc = IOTimerEventSource::timerEventSource(this,
-                                                    c_PM_Clamp_Timer_Expired);
+bool
+IOPMRequest::init( IOService * target, IOOptionBits type )
+{
+       if (!IOCommand::init()) {
+               return false;
+       }
 
-    IOWorkLoop * workLoop = getPMworkloop ();
+       fRequestType = type;
+       fTarget = target;
 
-    if ( !priv->clampTimerEventSrc || !workLoop ||
-       ( workLoop->addEventSource(  priv->clampTimerEventSrc) != kIOReturnSuccess) ) {
+       if (fTarget) {
+               fTarget->retain();
+       }
 
-    }
-  }
+       // Root node and root domain requests does not prevent the power tree from
+       // becoming quiescent.
 
-   priv->clampTimerEventSrc->setTimeout(300*USEC_PER_SEC, USEC_PER_SEC);
-*/
-}
+       fIsQuiesceBlocker = ((fTarget != gIOPMRootNode) &&
+           (fTarget != IOService::getPMRootDomain()));
 
-//*********************************************************************************
-// PM_Clamp_Timer_Expired
-//
-// called when clamp timer expires...set power state to 0.
-//*********************************************************************************
+       return true;
+}
 
-void IOService::PM_Clamp_Timer_Expired (void)
+void
+IOPMRequest::reset( void )
 {
-    if ( ! initialized ) 
-    {
-        // we're unloading
-        return;
-    }
+       assert( fWorkWaitCount == 0 );
+       assert( fFreeWaitCount == 0 );
 
-  changePowerStateToPriv (0);
-}
+       detachNextRequest();
+       detachRootRequest();
 
-//*********************************************************************************
-// c_PM_clamp_Timer_Expired (C Func)
-//
-// Called when our clamp timer expires...we will call the object method.
-//*********************************************************************************
+       if (fCompletionAction && (fRequestType == kIOPMRequestTypeQuiescePowerTree)) {
+               // Call the completion on PM work loop context
+               fCompletionAction(fCompletionTarget, fCompletionParam);
+               fCompletionAction = NULL;
+       }
 
-void c_PM_Clamp_Timer_Expired (OSObject * client, IOTimerEventSource *)
+       fRequestType = kIOPMRequestTypeInvalid;
+
+       if (fTarget) {
+               fTarget->release();
+               fTarget = NULL;
+       }
+}
+
+bool
+IOPMRequest::attachNextRequest( IOPMRequest * next )
 {
-    if (client)
-        ((IOService *)client)->PM_Clamp_Timer_Expired ();
+       bool ok = false;
+
+       if (!fRequestNext) {
+               // Postpone the execution of the next request after
+               // this request.
+               fRequestNext = next;
+               fRequestNext->fWorkWaitCount++;
+#if LOG_REQUEST_ATTACH
+               PM_LOG("Attached next: %p [0x%x] -> %p [0x%x, %u] %s\n",
+                   OBFUSCATE(this), fRequestType, OBFUSCATE(fRequestNext),
+                   fRequestNext->fRequestType,
+                   (uint32_t) fRequestNext->fWorkWaitCount,
+                   fTarget->getName());
+#endif
+               ok = true;
+       }
+       return ok;
 }
 
+bool
+IOPMRequest::detachNextRequest( void )
+{
+       bool ok = false;
+
+       if (fRequestNext) {
+               assert(fRequestNext->fWorkWaitCount);
+               if (fRequestNext->fWorkWaitCount) {
+                       fRequestNext->fWorkWaitCount--;
+               }
+#if LOG_REQUEST_ATTACH
+               PM_LOG("Detached next: %p [0x%x] -> %p [0x%x, %u] %s\n",
+                   OBFUSCATE(this), fRequestType, OBFUSCATE(fRequestNext),
+                   fRequestNext->fRequestType,
+                   (uint32_t) fRequestNext->fWorkWaitCount,
+                   fTarget->getName());
+#endif
+               fRequestNext = NULL;
+               ok = true;
+       }
+       return ok;
+}
 
-//*********************************************************************************
-// setPowerState
-//
-// Does nothing here.  This should be implemented in a subclass driver.
-//*********************************************************************************
+bool
+IOPMRequest::attachRootRequest( IOPMRequest * root )
+{
+       bool ok = false;
+
+       if (!fRequestRoot) {
+               // Delay the completion of the root request after
+               // this request.
+               fRequestRoot = root;
+               fRequestRoot->fFreeWaitCount++;
+#if LOG_REQUEST_ATTACH
+               PM_LOG("Attached root: %p [0x%x] -> %p [0x%x, %u] %s\n",
+                   OBFUSCATE(this), (uint32_t) fType, OBFUSCATE(fRequestRoot),
+                   (uint32_t) fRequestRoot->fType,
+                   (uint32_t) fRequestRoot->fFreeWaitCount,
+                   fTarget->getName());
+#endif
+               ok = true;
+       }
+       return ok;
+}
 
-IOReturn IOService::setPowerState ( unsigned long powerStateOrdinal, IOService* whatDevice )
+bool
+IOPMRequest::detachRootRequest( void )
 {
-    return IOPMNoErr;
+       bool ok = false;
+
+       if (fRequestRoot) {
+               assert(fRequestRoot->fFreeWaitCount);
+               if (fRequestRoot->fFreeWaitCount) {
+                       fRequestRoot->fFreeWaitCount--;
+               }
+#if LOG_REQUEST_ATTACH
+               PM_LOG("Detached root: %p [0x%x] -> %p [0x%x, %u] %s\n",
+                   OBFUSCATE(this), (uint32_t) fType, OBFUSCATE(fRequestRoot),
+                   (uint32_t) fRequestRoot->fType,
+                   (uint32_t) fRequestRoot->fFreeWaitCount,
+                   fTarget->getName());
+#endif
+               fRequestRoot = NULL;
+               ok = true;
+       }
+       return ok;
 }
 
+// MARK: -
+// MARK: IOPMRequestQueue
 
 //*********************************************************************************
-// maxCapabilityForDomainState
+// IOPMRequestQueue Class
 //
-// Finds the highest power state in the array whose input power
-// requirement is equal to the input parameter.  Where a more intelligent
-// decision is possible, override this in the subclassed driver.
+// Global queues. Queues are created once and never released.
 //*********************************************************************************
 
-unsigned long IOService::maxCapabilityForDomainState ( IOPMPowerFlags domainState )
+OSDefineMetaClassAndStructors( IOPMRequestQueue, IOEventSource );
+
+IOPMRequestQueue *
+IOPMRequestQueue::create( IOService * inOwner, Action inAction )
 {
-   int i;
+       IOPMRequestQueue * me = OSTypeAlloc(IOPMRequestQueue);
+       if (me && !me->init(inOwner, inAction)) {
+               me->release();
+               me = NULL;
+       }
+       return me;
+}
+
+bool
+IOPMRequestQueue::init( IOService * inOwner, Action inAction )
+{
+       if (!inAction || !IOEventSource::init(inOwner, (IOEventSourceAction)inAction)) {
+               return false;
+       }
 
-   if (pm_vars->theNumberOfPowerStates == 0 ) 
-   {
-       return 0;
-   }
-   for ( i = (pm_vars->theNumberOfPowerStates)-1; i >= 0; i-- ) 
-   {
-       if (  (domainState & pm_vars->thePowerStates[i].inputPowerRequirement) == pm_vars->thePowerStates[i].inputPowerRequirement ) 
-       {
-           return i;
-       }
-   }
-   return 0;
+       queue_init(&fQueue);
+       fLock = IOLockAlloc();
+       return fLock != NULL;
 }
 
+void
+IOPMRequestQueue::free( void )
+{
+       if (fLock) {
+               IOLockFree(fLock);
+               fLock = NULL;
+       }
+       return IOEventSource::free();
+}
 
-//*********************************************************************************
-// initialPowerStateForDomainState
-//
-// Finds the highest power state in the array whose input power
-// requirement is equal to the input parameter.  Where a more intelligent
-// decision is possible, override this in the subclassed driver.
-//*********************************************************************************
+void
+IOPMRequestQueue::queuePMRequest( IOPMRequest * request )
+{
+       assert(request);
+       IOLockLock(fLock);
+       queue_enter(&fQueue, request, typeof(request), fCommandChain);
+       IOLockUnlock(fLock);
+       if (workLoop) {
+               signalWorkAvailable();
+       }
+}
 
-unsigned long IOService::initialPowerStateForDomainState ( IOPMPowerFlags domainState )
+void
+IOPMRequestQueue::queuePMRequestChain( IOPMRequest ** requests, IOItemCount count )
 {
-    int i;
+       IOPMRequest * next;
+
+       assert(requests && count);
+       IOLockLock(fLock);
+       while (count--) {
+               next = *requests;
+               requests++;
+               queue_enter(&fQueue, next, typeof(next), fCommandChain);
+       }
+       IOLockUnlock(fLock);
+       if (workLoop) {
+               signalWorkAvailable();
+       }
+}
 
-    if (pm_vars->theNumberOfPowerStates == 0 ) 
-    {
-        return 0;
-    }
-    for ( i = (pm_vars->theNumberOfPowerStates)-1; i >= 0; i-- ) 
-    {
-        if (  (domainState & pm_vars->thePowerStates[i].inputPowerRequirement) == pm_vars->thePowerStates[i].inputPowerRequirement ) 
-        {
-            return i;
-        }
-    }
-    return 0;
+bool
+IOPMRequestQueue::checkForWork( void )
+{
+       Action          dqAction = (Action) action;
+       IOPMRequest *   request;
+       IOService *     target;
+       int             dequeueCount = 0;
+       bool            more = false;
+
+       IOLockLock( fLock );
+
+       while (!queue_empty(&fQueue)) {
+               if (dequeueCount++ >= kMaxDequeueCount) {
+                       // Allow other queues a chance to work
+                       more = true;
+                       break;
+               }
+
+               queue_remove_first(&fQueue, request, typeof(request), fCommandChain);
+               IOLockUnlock(fLock);
+               target = request->getTarget();
+               assert(target);
+               more |= (*dqAction)( target, request, this );
+               IOLockLock( fLock );
+       }
+
+       IOLockUnlock( fLock );
+       return more;
 }
 
+// MARK: -
+// MARK: IOPMWorkQueue
 
 //*********************************************************************************
-// powerStateForDomainState
+// IOPMWorkQueue Class
 //
-// Finds the highest power state in the array whose input power
-// requirement is equal to the input parameter.  Where a more intelligent
-// decision is possible, override this in the subclassed driver.
+// Queue of IOServicePM objects, each with a queue of IOPMRequest sharing the
+// same target.
 //*********************************************************************************
 
-unsigned long IOService::powerStateForDomainState ( IOPMPowerFlags domainState )
-{
-    int i;
+OSDefineMetaClassAndStructors( IOPMWorkQueue, IOEventSource );
 
-    if (pm_vars->theNumberOfPowerStates == 0 ) 
-    {
-        return 0;
-    }
-    for ( i = (pm_vars->theNumberOfPowerStates)-1; i >= 0; i-- ) 
-    {
-        if (  (domainState & pm_vars->thePowerStates[i].inputPowerRequirement) == pm_vars->thePowerStates[i].inputPowerRequirement ) 
-        {
-            return i;
-        }
-    }
-    return 0;
+IOPMWorkQueue *
+IOPMWorkQueue::create( IOService * inOwner, Action invoke, Action retire )
+{
+       IOPMWorkQueue * me = OSTypeAlloc(IOPMWorkQueue);
+       if (me && !me->init(inOwner, invoke, retire)) {
+               me->release();
+               me = NULL;
+       }
+       return me;
 }
 
+bool
+IOPMWorkQueue::init( IOService * inOwner, Action invoke, Action retire )
+{
+       if (!invoke || !retire ||
+           !IOEventSource::init(inOwner, (IOEventSourceAction)NULL)) {
+               return false;
+       }
 
-//*********************************************************************************
-// didYouWakeSystem
-//
-// Does nothing here.  This should be implemented in a subclass driver.
-//*********************************************************************************
+       queue_init(&fWorkQueue);
+
+       fInvokeAction  = invoke;
+       fRetireAction  = retire;
+       fConsumerCount = fProducerCount = 0;
 
-bool IOService::didYouWakeSystem  ( void )
+       return true;
+}
+
+bool
+IOPMWorkQueue::queuePMRequest( IOPMRequest * request, IOServicePM * pwrMgt )
 {
-    return false;
+       queue_head_t *  requestQueue;
+       bool            more  = false;
+       bool            empty;
+
+       assert( request );
+       assert( pwrMgt );
+       assert( onThread());
+       assert( queue_next(&request->fCommandChain) ==
+           queue_prev(&request->fCommandChain));
+
+       gIOPMBusyRequestCount++;
+
+       if (request->isQuiesceType()) {
+               if ((request->getTarget() == gIOPMRootNode) && !fQuiesceStartTime) {
+                       // Attach new quiesce request to all quiesce blockers in the queue
+                       fQuiesceStartTime = mach_absolute_time();
+                       attachQuiesceRequest(request);
+                       fQuiesceRequest = request;
+               }
+       } else if (fQuiesceRequest && request->isQuiesceBlocker()) {
+               // Attach the new quiesce blocker to the blocked quiesce request
+               request->attachNextRequest(fQuiesceRequest);
+       }
+
+       // Add new request to the tail of the per-service request queue.
+       // Then immediately check the request queue to minimize latency
+       // if the queue was empty.
+
+       requestQueue = &pwrMgt->RequestHead;
+       empty = queue_empty(requestQueue);
+       queue_enter(requestQueue, request, typeof(request), fCommandChain);
+       if (empty) {
+               more = checkRequestQueue(requestQueue, &empty);
+               if (!empty) {
+                       // Request just added is blocked, add its target IOServicePM
+                       // to the work queue.
+                       assert( queue_next(&pwrMgt->WorkChain) ==
+                           queue_prev(&pwrMgt->WorkChain));
+
+                       queue_enter(&fWorkQueue, pwrMgt, typeof(pwrMgt), WorkChain);
+                       fQueueLength++;
+                       PM_LOG3("IOPMWorkQueue: [%u] added %s@%p to queue\n",
+                           fQueueLength, pwrMgt->Name, OBFUSCATE(pwrMgt));
+               }
+       }
+
+       return more;
 }
 
+bool
+IOPMWorkQueue::checkRequestQueue( queue_head_t * requestQueue, bool * empty )
+{
+       IOPMRequest *   request;
+       IOService *     target;
+       bool            more = false;
+       bool            done = false;
+
+       assert(!queue_empty(requestQueue));
+       do {
+               request = (typeof(request))queue_first(requestQueue);
+               if (request->isWorkBlocked()) {
+                       break; // request dispatch blocked on attached request
+               }
+               target = request->getTarget();
+               if (fInvokeAction) {
+                       done = (*fInvokeAction)( target, request, this );
+               } else {
+                       PM_LOG("PM request 0x%x dropped\n", request->getType());
+                       done = true;
+               }
+               if (!done) {
+                       break; // PM state machine blocked
+               }
+               assert(gIOPMBusyRequestCount > 0);
+               if (gIOPMBusyRequestCount) {
+                       gIOPMBusyRequestCount--;
+               }
+
+               if (request == fQuiesceRequest) {
+                       fQuiesceRequest = NULL;
+               }
+
+               queue_remove_first(requestQueue, request, typeof(request), fCommandChain);
+               more |= (*fRetireAction)( target, request, this );
+               done = queue_empty(requestQueue);
+       } while (!done);
+
+       *empty = done;
+
+       if (more) {
+               // Retired a request that may unblock a previously visited request
+               // that is still waiting on the work queue. Must trigger another
+               // queue check.
+               fProducerCount++;
+       }
+
+       return more;
+}
 
-//*********************************************************************************
-// powerStateWillChangeTo
-//
-// Does nothing here.  This should be implemented in a subclass driver.
-//*********************************************************************************
+bool
+IOPMWorkQueue::checkForWork( void )
+{
+       IOServicePM *   entry;
+       IOServicePM *   next;
+       bool            more = false;
+       bool            empty;
+
+#if WORK_QUEUE_STATS
+       fStatCheckForWork++;
+#endif
+
+       // Iterate over all IOServicePM entries in the work queue,
+       // and check each entry's request queue.
+
+       while (fConsumerCount != fProducerCount) {
+               PM_LOG3("IOPMWorkQueue: checkForWork %u %u\n",
+                   fProducerCount, fConsumerCount);
+
+               fConsumerCount = fProducerCount;
+
+#if WORK_QUEUE_STATS
+               if (queue_empty(&fWorkQueue)) {
+                       fStatQueueEmpty++;
+                       break;
+               }
+               fStatScanEntries++;
+               uint32_t cachedWorkCount = gIOPMWorkInvokeCount;
+#endif
+
+               __IGNORE_WCASTALIGN(entry = (typeof(entry))queue_first(&fWorkQueue));
+               while (!queue_end(&fWorkQueue, (queue_entry_t) entry)) {
+                       more |= checkRequestQueue(&entry->RequestHead, &empty);
+
+                       // Get next entry, points to head if current entry is last.
+                       __IGNORE_WCASTALIGN(next = (typeof(next))queue_next(&entry->WorkChain));
+
+                       // if request queue is empty, remove IOServicePM from work queue.
+                       if (empty) {
+                               assert(fQueueLength);
+                               if (fQueueLength) {
+                                       fQueueLength--;
+                               }
+                               PM_LOG3("IOPMWorkQueue: [%u] removed %s@%p from queue\n",
+                                   fQueueLength, entry->Name, OBFUSCATE(entry));
+                               queue_remove(&fWorkQueue, entry, typeof(entry), WorkChain);
+                       }
+                       entry = next;
+               }
+
+#if WORK_QUEUE_STATS
+               if (cachedWorkCount == gIOPMWorkInvokeCount) {
+                       fStatNoWorkDone++;
+               }
+#endif
+       }
+
+       return more;
+}
 
-IOReturn IOService::powerStateWillChangeTo ( IOPMPowerFlags, unsigned long, IOService*)
+void
+IOPMWorkQueue::signalWorkAvailable( void )
 {
-    return 0;
+       fProducerCount++;
+       IOEventSource::signalWorkAvailable();
 }
 
+void
+IOPMWorkQueue::incrementProducerCount( void )
+{
+       fProducerCount++;
+}
 
-//*********************************************************************************
-// powerStateDidChangeTo
-//
-// Does nothing here.  This should be implemented in a subclass driver.
-//*********************************************************************************
+void
+IOPMWorkQueue::attachQuiesceRequest( IOPMRequest * quiesceRequest )
+{
+       IOServicePM *   entry;
+       IOPMRequest *   request;
+
+       if (queue_empty(&fWorkQueue)) {
+               return;
+       }
+
+       queue_iterate(&fWorkQueue, entry, typeof(entry), WorkChain)
+       {
+               queue_iterate(&entry->RequestHead, request, typeof(request), fCommandChain)
+               {
+                       // Attach the quiesce request to any request in the queue that
+                       // is not linked to a next request. These requests will block
+                       // the quiesce request.
+
+                       if (request->isQuiesceBlocker()) {
+                               request->attachNextRequest(quiesceRequest);
+                       }
+               }
+       }
+}
 
-IOReturn IOService::powerStateDidChangeTo ( IOPMPowerFlags, unsigned long, IOService*)
+void
+IOPMWorkQueue::finishQuiesceRequest( IOPMRequest * quiesceRequest )
 {
-    return 0;
+       if (fQuiesceRequest && (quiesceRequest == fQuiesceRequest) &&
+           (fQuiesceStartTime != 0)) {
+               fInvokeAction = NULL;
+               fQuiesceFinishTime = mach_absolute_time();
+       }
 }
 
+// MARK: -
+// MARK: IOPMCompletionQueue
 
 //*********************************************************************************
-// powerChangeDone
-//
-// Does nothing here.  This should be implemented in a subclass policy-maker.
+// IOPMCompletionQueue Class
 //*********************************************************************************
 
-void IOService::powerChangeDone ( unsigned long )
+OSDefineMetaClassAndStructors( IOPMCompletionQueue, IOEventSource );
+
+IOPMCompletionQueue *
+IOPMCompletionQueue::create( IOService * inOwner, Action inAction )
 {
+       IOPMCompletionQueue * me = OSTypeAlloc(IOPMCompletionQueue);
+       if (me && !me->init(inOwner, inAction)) {
+               me->release();
+               me = NULL;
+       }
+       return me;
 }
 
+bool
+IOPMCompletionQueue::init( IOService * inOwner, Action inAction )
+{
+       if (!inAction || !IOEventSource::init(inOwner, (IOEventSourceAction)inAction)) {
+               return false;
+       }
 
-//*********************************************************************************
-// newTemperature
-//
-// Does nothing here.  This should be implemented in a subclass driver.
-//*********************************************************************************
+       queue_init(&fQueue);
+       return true;
+}
+
+bool
+IOPMCompletionQueue::queuePMRequest( IOPMRequest * request )
+{
+       bool more;
 
-IOReturn IOService::newTemperature ( long currentTemp, IOService * whichZone )
+       assert(request);
+       // unblock dependent request
+       more = request->detachNextRequest();
+       queue_enter(&fQueue, request, typeof(request), fCommandChain);
+       return more;
+}
 
+bool
+IOPMCompletionQueue::checkForWork( void )
 {
-    return IOPMNoErr;
+       Action          dqAction = (Action) action;
+       IOPMRequest *   request;
+       IOPMRequest *   next;
+       IOService *     target;
+       bool            more = false;
+
+       request = (typeof(request))queue_first(&fQueue);
+       while (!queue_end(&fQueue, (queue_entry_t) request)) {
+               next = (typeof(next))queue_next(&request->fCommandChain);
+               if (!request->isFreeBlocked()) {
+                       queue_remove(&fQueue, request, typeof(request), fCommandChain);
+                       target = request->getTarget();
+                       assert(target);
+                       more |= (*dqAction)( target, request, this );
+               }
+               request = next;
+       }
+
+       return more;
 }
 
+// MARK: -
+// MARK: IOServicePM
 
-#undef super
-#define super OSObject
+OSDefineMetaClassAndStructors(IOServicePM, OSObject)
 
-OSDefineMetaClassAndStructors(IOPMprot, OSObject)
 //*********************************************************************************
 // serialize
 //
-// Serialize protected instance variables for debug output.
+// Serialize IOServicePM for debugging.
 //*********************************************************************************
-bool IOPMprot::serialize(OSSerialize *s) const
-{
-    OSString * theOSString;
-    char * buffer;
-    char * ptr;
-    int i;
-    bool       rtn_code;
 
-    buffer = ptr = IONew(char, 2000);
-    if(!buffer)
-        return false;
-
-    ptr += sprintf(ptr,"{ theNumberOfPowerStates = %d, ",(unsigned int)theNumberOfPowerStates);
-
-    if ( theNumberOfPowerStates != 0 ) {
-        ptr += sprintf(ptr,"version %d, ",(unsigned int)thePowerStates[0].version);
-    }
-
-    if ( theNumberOfPowerStates != 0 ) {
-        for ( i = 0; i < (int)theNumberOfPowerStates; i++ ) {
-            ptr += sprintf(ptr,"power state %d = { ",i);
-            ptr += sprintf(ptr,"capabilityFlags %08x, ",(unsigned int)thePowerStates[i].capabilityFlags);
-            ptr += sprintf(ptr,"outputPowerCharacter %08x, ",(unsigned int)thePowerStates[i].outputPowerCharacter);
-            ptr += sprintf(ptr,"inputPowerRequirement %08x, ",(unsigned int)thePowerStates[i].inputPowerRequirement);
-            ptr += sprintf(ptr,"staticPower %d, ",(unsigned int)thePowerStates[i].staticPower);
-            ptr += sprintf(ptr,"unbudgetedPower %d, ",(unsigned int)thePowerStates[i].unbudgetedPower);
-            ptr += sprintf(ptr,"powerToAttain %d, ",(unsigned int)thePowerStates[i].powerToAttain);
-            ptr += sprintf(ptr,"timeToAttain %d, ",(unsigned int)thePowerStates[i].timeToAttain);
-            ptr += sprintf(ptr,"settleUpTime %d, ",(unsigned int)thePowerStates[i].settleUpTime);
-            ptr += sprintf(ptr,"timeToLower %d, ",(unsigned int)thePowerStates[i].timeToLower);
-            ptr += sprintf(ptr,"settleDownTime %d, ",(unsigned int)thePowerStates[i].settleDownTime);
-            ptr += sprintf(ptr,"powerDomainBudget %d }, ",(unsigned int)thePowerStates[i].powerDomainBudget);
-        }
-    }
+static void
+setPMProperty( OSDictionary * dict, const char * key, uint64_t value )
+{
+       OSNumber * num = OSNumber::withNumber(value, sizeof(value) * 8);
+       if (num) {
+               dict->setObject(key, num);
+               num->release();
+       }
+}
 
-    ptr += sprintf(ptr,"aggressiveness = %d, ",(unsigned int)aggressiveness);
-    ptr += sprintf(ptr,"myCurrentState = %d, ",(unsigned int)myCurrentState);
-    ptr += sprintf(ptr,"parentsCurrentPowerFlags = %08x, ",(unsigned int)parentsCurrentPowerFlags);
-    ptr += sprintf(ptr,"maxCapability = %d }",(unsigned int)maxCapability);
+IOReturn
+IOServicePM::gatedSerialize( OSSerialize * s  ) const
+{
+       OSDictionary *  dict;
+       bool            ok = false;
+       int             powerClamp = -1;
+       int             dictSize = 6;
+
+       if (IdleTimerPeriod) {
+               dictSize += 4;
+       }
+
+       if (PMActions.parameter & kPMActionsFlagLimitPower) {
+               dictSize += 1;
+               powerClamp = 0;
+               if (PMActions.parameter &
+                   (kPMActionsFlagIsDisplayWrangler | kPMActionsFlagIsGraphicsDevice)) {
+                       powerClamp++;
+               }
+       }
+
+#if WORK_QUEUE_STATS
+       if (gIOPMRootNode == ControllingDriver) {
+               dictSize += 4;
+       }
+#endif
+
+       if (PowerClients) {
+               dict = OSDictionary::withDictionary(
+                       PowerClients, PowerClients->getCount() + dictSize);
+       } else {
+               dict = OSDictionary::withCapacity(dictSize);
+       }
+
+       if (dict) {
+               setPMProperty(dict, "CurrentPowerState", CurrentPowerState);
+               setPMProperty(dict, "CapabilityFlags", CurrentCapabilityFlags);
+               if (NumberOfPowerStates) {
+                       setPMProperty(dict, "MaxPowerState", NumberOfPowerStates - 1);
+               }
+               if (DesiredPowerState != CurrentPowerState) {
+                       setPMProperty(dict, "DesiredPowerState", DesiredPowerState);
+               }
+               if (kIOPM_Finished != MachineState) {
+                       setPMProperty(dict, "MachineState", MachineState);
+               }
+               if (DeviceOverrideEnabled) {
+                       dict->setObject("PowerOverrideOn", kOSBooleanTrue);
+               }
+               if (powerClamp >= 0) {
+                       setPMProperty(dict, "PowerClamp", powerClamp);
+               }
+
+               if (IdleTimerPeriod) {
+                       AbsoluteTime    now;
+                       AbsoluteTime    delta;
+                       uint64_t        nsecs;
+
+                       clock_get_uptime(&now);
+
+                       // The idle timer period in milliseconds
+                       setPMProperty(dict, "IdleTimerPeriod", NextIdleTimerPeriod * 1000ULL);
+
+                       // Number of tickles since the last idle timer expiration
+                       setPMProperty(dict, "ActivityTickles", ActivityTickleCount);
+
+                       if (AbsoluteTime_to_scalar(&DeviceActiveTimestamp)) {
+                               // Milliseconds since the last activity tickle
+                               delta = now;
+                               SUB_ABSOLUTETIME(&delta, &DeviceActiveTimestamp);
+                               absolutetime_to_nanoseconds(delta, &nsecs);
+                               setPMProperty(dict, "TimeSinceLastTickle", NS_TO_MS(nsecs));
+                       }
+
+                       if (!IdleTimerStopped && AbsoluteTime_to_scalar(&IdleTimerStartTime)) {
+                               // Idle timer elapsed time in milliseconds
+                               delta = now;
+                               SUB_ABSOLUTETIME(&delta, &IdleTimerStartTime);
+                               absolutetime_to_nanoseconds(delta, &nsecs);
+                               setPMProperty(dict, "IdleTimerElapsedTime", NS_TO_MS(nsecs));
+                       }
+               }
+
+#if WORK_QUEUE_STATS
+               if (gIOPMRootNode == Owner) {
+                       setPMProperty(dict, "WQ-CheckForWork",
+                           gIOPMWorkQueue->fStatCheckForWork);
+                       setPMProperty(dict, "WQ-ScanEntries",
+                           gIOPMWorkQueue->fStatScanEntries);
+                       setPMProperty(dict, "WQ-QueueEmpty",
+                           gIOPMWorkQueue->fStatQueueEmpty);
+                       setPMProperty(dict, "WQ-NoWorkDone",
+                           gIOPMWorkQueue->fStatNoWorkDone);
+               }
+#endif
+
+               if (HasAdvisoryDesire && !gIOPMAdvisoryTickleEnabled) {
+                       // Don't report advisory tickle when it has no influence
+                       dict->removeObject(gIOPMPowerClientAdvisoryTickle);
+               }
+
+               ok = dict->serialize(s);
+               dict->release();
+       }
+
+       return ok ? kIOReturnSuccess : kIOReturnNoMemory;
+}
 
-    theOSString = OSString::withCString(buffer);
-    rtn_code = theOSString->serialize(s);
-    theOSString->release();
-    IODelete(buffer, char, 2000);
+bool
+IOServicePM::serialize( OSSerialize * s ) const
+{
+       IOReturn ret = kIOReturnNotReady;
+
+       if (gIOPMWatchDogThread == current_thread()) {
+               // Calling without lock as this data is collected for debug purpose, before reboot.
+               // The workloop is probably already hung in state machine.
+               ret = gatedSerialize(s);
+       } else if (gIOPMWorkLoop) {
+               ret = gIOPMWorkLoop->runAction(
+                       OSMemberFunctionCast(IOWorkLoop::Action, this, &IOServicePM::gatedSerialize),
+                       (OSObject *) this, (void *) s);
+       }
+
+       return kIOReturnSuccess == ret;
+}
 
-    return rtn_code;
+void
+IOServicePM::pmPrint(
+       uint32_t        event,
+       uintptr_t       param1,
+       uintptr_t       param2 ) const
+{
+       gPlatform->PMLog(Name, event, param1, param2);
 }
 
+void
+IOServicePM::pmTrace(
+       uint32_t        event,
+       uint32_t        eventFunc,
+       uintptr_t       param1,
+       uintptr_t       param2 ) const
+{
+       uintptr_t nameAsArg = 0;
 
-#undef super
-#define super OSObject
+       assert(event < KDBG_CODE_MAX);
+       assert((eventFunc & ~KDBG_FUNC_MASK) == 0);
 
-OSDefineMetaClassAndStructors(IOPMpriv, OSObject)
-//*********************************************************************************
-// serialize
-//
-// Serialize private instance variables for debug output.
-//*********************************************************************************
-bool IOPMpriv::serialize(OSSerialize *s) const
-{
-    OSString *                 theOSString;
-    bool                       rtn_code;
-    char *                     buffer;
-    char *                     ptr;
-    IOPMinformee *             nextObject;
-
-    buffer = ptr = IONew(char, 2000);
-    if(!buffer)
-        return false;
-
-    ptr += sprintf(ptr,"{ this object = %08x",(unsigned int)owner);
-    if ( we_are_root ) {
-        ptr += sprintf(ptr," (root)");
-    }
-    ptr += sprintf(ptr,", ");
-
-    nextObject = interestedDrivers->firstInList();                     // display interested drivers
-    while (  nextObject != NULL ) {
-        ptr += sprintf(ptr,"interested driver = %08x, ",(unsigned int)nextObject->whatObject);
-        nextObject  =  interestedDrivers->nextInList(nextObject);
-    }
-
-    if ( machine_state != kIOPM_Finished ) {
-        ptr += sprintf(ptr,"machine_state = %d, ",(unsigned int)machine_state);
-        ptr += sprintf(ptr,"driver_timer = %d, ",(unsigned int)driver_timer);
-        ptr += sprintf(ptr,"settle_time = %d, ",(unsigned int)settle_time);
-        ptr += sprintf(ptr,"head_note_flags = %08x, ",(unsigned int)head_note_flags);
-        ptr += sprintf(ptr,"head_note_state = %d, ",(unsigned int)head_note_state);
-        ptr += sprintf(ptr,"head_note_outputFlags = %08x, ",(unsigned int)head_note_outputFlags);
-        ptr += sprintf(ptr,"head_note_domainState = %08x, ",(unsigned int)head_note_domainState);
-        ptr += sprintf(ptr,"head_note_capabilityFlags = %08x, ",(unsigned int)head_note_capabilityFlags);
-        ptr += sprintf(ptr,"head_note_pendingAcks = %d, ",(unsigned int)head_note_pendingAcks);
-    }
-
-    if ( device_overrides ) {
-        ptr += sprintf(ptr,"device overrides, ");
-    }
-    ptr += sprintf(ptr,"driverDesire = %d, ",(unsigned int)driverDesire);
-    ptr += sprintf(ptr,"deviceDesire = %d, ",(unsigned int)deviceDesire);
-    ptr += sprintf(ptr,"ourDesiredPowerState = %d, ",(unsigned int)ourDesiredPowerState);
-    ptr += sprintf(ptr,"previousRequest = %d }",(unsigned int)previousRequest);
-
-    theOSString =  OSString::withCString(buffer);
-    rtn_code = theOSString->serialize(s);
-    theOSString->release();
-    IODelete(buffer, char, 2000);
-
-    return rtn_code;
-}
+       // Copy the first characters of the name into an uintptr_t.
+       // NULL termination is not required.
+       strncpy((char*)&nameAsArg, Name, sizeof(nameAsArg));
 
+       IOTimeStampConstant(IODBG_POWER(event) | eventFunc, nameAsArg, (uintptr_t)Owner->getRegistryEntryID(), (uintptr_t)(OBFUSCATE(param1)), (uintptr_t)(OBFUSCATE(param2)));
+}