]> git.saurik.com Git - apple/xnu.git/blobdiff - iokit/Kernel/IOServicePM.cpp
xnu-6153.61.1.tar.gz
[apple/xnu.git] / iokit / Kernel / IOServicePM.cpp
index 5b5cc0b8a414713610e3a65a9f74ac3376087cea..5cdc56a78209b57c92be5b383ea728a1dc7a3784 100644 (file)
@@ -1,8 +1,8 @@
 /*
- * Copyright (c) 1998-2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2016 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- * 
+ *
  * 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
  * 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,
@@ -22,7 +22,7 @@
  * 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_OSREFERENCE_LICENSE_HEADER_END@
  */
 
 #include <IOKit/IOMessage.h>
 #include <IOKit/IOPlatformExpert.h>
 #include <IOKit/IOService.h>
-#include <IOKit/IOTimerEventSource.h>
+#include <IOKit/IOEventSource.h>
 #include <IOKit/IOWorkLoop.h>
 #include <IOKit/IOCommand.h>
+#include <IOKit/IOTimeStamp.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/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"
 
+
 static void settle_timer_expired(thread_call_param_t, thread_call_param_t);
-static void PM_idle_timer_expired(OSObject *, IOTimerEventSource *);
-void        tellAppWithResponse(OSObject * object, void * context) { /*empty*/ }
-void        tellClientWithResponse(OSObject * object, void * context) { /*empty*/ }
-void        tellClient(OSObject * object, void * context);
-IOReturn    serializedAllowPowerChange(OSObject *, void *, void *, void *, void *);
+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 )
+static uint64_t
+computeTimeDeltaNS( const AbsoluteTime * start )
 {
-    AbsoluteTime    now;
-    uint64_t        nsec;
+       AbsoluteTime    now;
+       uint64_t        nsec;
 
-    clock_get_uptime(&now);
-    SUB_ABSOLUTETIME(&now, start);
-    absolutetime_to_nanoseconds(now, &nsec);
-    return nsec;
+       clock_get_uptime(&now);
+       SUB_ABSOLUTETIME(&now, start);
+       absolutetime_to_nanoseconds(now, &nsec);
+       return nsec;
 }
 
+#if PM_VARS_SUPPORT
 OSDefineMetaClassAndStructors(IOPMprot, OSObject)
+#endif
 
-// log setPowerStates longer than (ns):
-#define LOG_SETPOWER_TIMES      (50ULL * 1000ULL * 1000ULL)
-// log app responses longer than (ns):
-#define LOG_APP_RESPONSE_TIMES  (100ULL * 1000ULL * 1000ULL)
-
-//*********************************************************************************
+//******************************************************************************
 // 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 )
+{
+       uint32_t type = kIOPMRequestTypeInvalid;
+       if (gIOPMRequest) {
+               type = gIOPMRequest->getType();
+       }
+       return type;
+}
+
+static IOPMRequestTag
+getPMRequestTag( void )
+{
+       IOPMRequestTag tag = 0;
+       if (gIOPMRequest &&
+           (gIOPMRequest->getType() == kIOPMRequestTypeRequestPowerStateOverride)) {
+               tag = gIOPMRequest->fRequestTag;
+       }
+       return tag;
+}
 
-static bool                 gIOPMInitialized   = false;
-static IOItemCount          gIOPMBusyCount     = 0;
-static IOWorkLoop *         gIOPMWorkLoop      = 0;
-static IOPMRequestQueue *   gIOPMRequestQueue  = 0;
-static IOPMRequestQueue *   gIOPMReplyQueue    = 0;
-static IOPMRequestQueue *   gIOPMFreeQueue     = 0;
+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_ERROR(x...)          do { kprintf(x); IOLog(x); } while (false)
-#define PM_DEBUG(x...)          do { kprintf(x); } while (false)
+#define PM_LOG1(x...)               do {  \
+                                   if (kIOLogDebugPower & gIOKitDebug) \
+                                       kprintf(x); } while (false)
 
-#define PM_TRACE(x...)          do {  \
-       if (kIOLogDebugPower & gIOKitDebug) kprintf(x); } while (false)
+#define PM_LOG2(x...)               do {  \
+                                   if (kIOLogDebugPower & gIOKitDebug) \
+                                       kprintf(x); } while (false)
 
-#define PM_CONNECT(x...)
+#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()                   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
+};
 
-#define ns_per_us                     1000
-#define k30seconds                    (30*1000000)
-#define kMinAckTimeoutTicks           (10*1000000)
-#define kIOPMTardyAckSPSKey           "IOPMTardyAckSetPowerState"
-#define kIOPMTardyAckPSCKey           "IOPMTardyAckPowerStateChange"
-#define kPwrMgtKey                    "IOPowerManagement"
+#define MS_PUSH(n)  \
+    do { assert(kIOPM_BadMachineState == fSavedMachineState); \
+        assert(kIOPM_BadMachineState != n); \
+        fSavedMachineState = n; } while (false)
 
-#define OUR_PMLog(t, a, b) \
-    do { fPlatform->PMLog( fName, t, a, b); } while(0)
+#define MS_POP()    \
+    do { assert(kIOPM_BadMachineState != fSavedMachineState); \
+        fMachineState = fSavedMachineState; \
+        fSavedMachineState = kIOPM_BadMachineState; } while (false)
 
-#define NS_TO_MS(nsec)                ((int)((nsec) / 1000000ULL))
+#define PM_ACTION_0(a) \
+    do { if (fPMActions.a) { \
+        (fPMActions.a)(fPMActions.target, this, &fPMActions); } \
+        } while (false)
 
-#if CONFIG_EMBEDDED
-#define SUPPORT_IDLE_CANCEL                            1
-#endif
+#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)
+
+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.
 //*********************************************************************************
 
 enum {
-    kIOPM_OurChangeTellClientsPowerDown                 = 1,
-    kIOPM_OurChangeTellPriorityClientsPowerDown         = 2,
-    kIOPM_OurChangeNotifyInterestedDriversWillChange    = 3,
-    kIOPM_OurChangeSetPowerState                        = 4,
-    kIOPM_OurChangeWaitForPowerSettle                   = 5,
-    kIOPM_OurChangeNotifyInterestedDriversDidChange     = 6,
-    kIOPM_OurChangeFinish                               = 7,
-    kIOPM_ParentDownTellPriorityClientsPowerDown        = 8,
-    kIOPM_ParentDownNotifyInterestedDriversWillChange   = 9,
-    /* 10 not used */
-    kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange = 11,
-    kIOPM_ParentDownSetPowerState                       = 12,
-    kIOPM_ParentDownWaitForPowerSettle                  = 13,
-    kIOPM_ParentDownAcknowledgeChange                   = 14,
-    kIOPM_ParentUpSetPowerState                         = 15,
-    /* 16 not used */
-    kIOPM_ParentUpWaitForSettleTime                     = 17,
-    kIOPM_ParentUpNotifyInterestedDriversDidChange      = 18,
-    kIOPM_ParentUpAcknowledgePowerChange                = 19,
-    kIOPM_Finished                                      = 20,
-    kIOPM_DriverThreadCallDone                          = 21,
-    kIOPM_NotifyChildrenDone                            = 22
+       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
 };
 
-
- /*
- Power Management defines a few roles that drivers can play in their own, 
- and other drivers', power management. We briefly define those here.
- Many drivers implement their policy maker and power controller within the same 
- IOService object, but that is not required. 
-== Policy Maker == 
- * Virtual IOService PM methods a "policy maker" may implement
-    * maxCapabilityForDomainState()
-    * initialPowerStateForDomainState()
-    * powerStateForDomainState()
-    
- * Virtual IOService PM methods a "policy maker" may CALL
-    * PMinit()
-== Power Controller ==
- * Virtual IOService PM methods a "power controller" may implement
-    * setPowerState() 
- * Virtual IOService PM methods a "power controller" may CALL
-    * joinPMtree()
-    * registerPowerDriver()
-=======================
- 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 through different code paths.
- We maintain a queue of "change notifications," or change notes.
-    * Usually the queue is empty. 
-    * When it isn't, usually there is one change note in it 
-    * It's possible to have more than one power state change pending at one 
-        time, so 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.
- == SelfInitiated ==
- 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.
- == PowerDomainDownInitiated ==
-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.
- == PowerDomainUpInitiated ==
-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 power domain state 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, 
-    * We will not take advantage of a change to a higher domain state, because 
-        we have no need of the higher power. In such cases, 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.
- == 4 Paths Through State Machine ==
- 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.
- == 5. No Need To change ==
- 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.
- == 1. OurChange Down ==    XXX gvdl
- 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 
-            "msSetPowerState".  
-        -> Otherwise, we start the ack timer and wait for the stragglers to 
-            acknowlege by calling acknowledgePowerChange.  
-            -> We move on to state "msSetPowerState" when all the 
-                stragglers have acknowledged, or when the ack timer expires on 
-                all those which didn't acknowledge.  
- In "msSetPowerState" 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 
-        "msWaitForPowerSettle".
-    -> 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 "msWaitForPowerSettle", 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 "msNotifyInterestedDriversDidChange".  
-    -> Otherwise, we set the settle timer and wait. When it expires, we move on.  
- In "msNotifyInterestedDriversDidChange" 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 "msFinish".  
-    -> 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 "msFinish".
- In "msFinish" we remove the used change note from the head of the queue 
- and start the next one if one exists.
-
- == 2. Parent Change Down ==
- Start at Stage 2 of OurChange Down    XXX gvdl
-
- == 3. Change Up ==
- Start at Stage 4 of OurChange Down    XXX gvdl
-
-Note all parent requested changes need to acknowledge the power has changed to the parent when done.
- */
-
 //*********************************************************************************
-// [public virtual] PMinit
+// [public] PMinit
 //
 // Initialize power management.
 //*********************************************************************************
 
-void IOService::PMinit ( void )
+void
+IOService::PMinit( void )
 {
-    if ( !initialized )
-       {
-               if ( !gIOPMInitialized )
-               {
+       if (!initialized) {
+               if (!gIOPMInitialized) {
+                       gPlatform = getPlatform();
                        gIOPMWorkLoop = IOWorkLoop::workLoop();
-                       if (gIOPMWorkLoop)
-                       {
+                       if (gIOPMWorkLoop) {
                                gIOPMRequestQueue = IOPMRequestQueue::create(
                                        this, OSMemberFunctionCast(IOPMRequestQueue::Action,
-                                               this, &IOService::servicePMRequestQueue));
+                                       this, &IOService::actionPMRequestQueue));
 
                                gIOPMReplyQueue = IOPMRequestQueue::create(
                                        this, OSMemberFunctionCast(IOPMRequestQueue::Action,
-                                               this, &IOService::servicePMReplyQueue));
+                                       this, &IOService::actionPMReplyQueue));
 
-                               gIOPMFreeQueue = IOPMRequestQueue::create(
-                                       this, OSMemberFunctionCast(IOPMRequestQueue::Action,
-                                               this, &IOService::servicePMFreeQueue));
+                               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)
-                               {
+                                   kIOReturnSuccess) {
                                        gIOPMRequestQueue->release();
-                                       gIOPMRequestQueue = 0;
+                                       gIOPMRequestQueue = NULL;
                                }
 
                                if (gIOPMWorkLoop->addEventSource(gIOPMReplyQueue) !=
-                                       kIOReturnSuccess)
-                               {
+                                   kIOReturnSuccess) {
                                        gIOPMReplyQueue->release();
-                                       gIOPMReplyQueue = 0;
+                                       gIOPMReplyQueue = NULL;
                                }
 
-                               if (gIOPMWorkLoop->addEventSource(gIOPMFreeQueue) !=
-                                       kIOReturnSuccess)
-                               {
-                                       gIOPMFreeQueue->release();
-                                       gIOPMFreeQueue = 0;
+                               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 && gIOPMFreeQueue)
+                       if (gIOPMRequestQueue && gIOPMReplyQueue && gIOPMCompletionQueue) {
                                gIOPMInitialized = true;
+                       }
                }
-               if (!gIOPMInitialized)
+               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;
+               }
 
-        pwrMgt = new IOServicePM;
-        pwrMgt->init();
-        setProperty(kPwrMgtKey, pwrMgt);
-
-        fOwner                      = this;
-        fWeAreRoot                  = false;
-        fPMLock                     = IOLockAlloc();
-        fInterestedDrivers          = new IOPMinformeeList;
-        fInterestedDrivers->initialize();
-        fDesiredPowerState          = 0;
-        fDriverDesire               = 0;
-        fDeviceDesire               = 0;
-        fInitialChange              = true;
-        fNeedToBecomeUsable         = false;
-        fPreviousRequest            = 0;
-        fDeviceOverrides            = false;
-        fMachineState               = kIOPM_Finished;
-        fIdleTimerEventSource       = NULL;
-        fIdleTimerMinPowerState     = 0;
-        fActivityLock               = IOLockAlloc();
-        fClampOn                    = false;
-        fStrictTreeOrder            = false;
-        fActivityTicklePowerState   = -1;
-        fControllingDriver          = NULL;
-        fPowerStates                = NULL;
-        fNumberOfPowerStates        = 0;
-        fCurrentPowerState          = 0;
-        fParentsCurrentPowerFlags   = 0;
-        fMaxCapability              = 0;
-        fName                       = getName();
-        fPlatform                   = getPlatform();
-        fParentsKnowState           = false;
-        fSerialNumber               = 0;
-        fResponseArray              = NULL;
-        fDoNotPowerDown             = true;
-        fCurrentPowerConsumption    = kIOPMUnknown;
-
-        for (unsigned int i = 0; i <= kMaxType; i++)
-        {
-               fAggressivenessValue[i] = 0;
-               fAggressivenessValid[i]  = false;
-        }
-
-        fAckTimer = thread_call_allocate(
+               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(
+               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 = fPlatform;
-            fPMVars = prot;
-            pm_vars = prot;
+               IOPMprot * prot = new IOPMprot;
+               if (prot) {
+                       prot->init();
+                       prot->ourName = fName;
+                       prot->thePlatform = gPlatform;
+                       fPMVars = prot;
+                       pm_vars = prot;
                }
 #else
-        pm_vars = (IOPMprot *) true;
+               pm_vars = (void *) (uintptr_t) true;
 #endif
 
-        initialized = true;
-    }
+               initialized = true;
+       }
 }
 
 //*********************************************************************************
-// [public] PMfree
+// [private] PMfree
 //
-// Free up the data created in PMinit, if it exists.
+// Free the data created by PMinit. Only called from IOService::free().
 //*********************************************************************************
 
-void IOService::PMfree ( void )
+void
+IOService::PMfree( void )
 {
        initialized = false;
-    pm_vars = 0;
+       pm_vars = NULL;
 
-    if ( pwrMgt )
-       {
+       if (pwrMgt) {
                assert(fMachineState == kIOPM_Finished);
                assert(fInsertInterestSet == NULL);
                assert(fRemoveInterestSet == NULL);
-        assert(fNotifyChildArray  == NULL);
-
-        if ( fIdleTimerEventSource != NULL ) {
-            getPMworkloop()->removeEventSource(fIdleTimerEventSource);
-            fIdleTimerEventSource->release();
-            fIdleTimerEventSource = 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 ( fDriverCallEntry ) {
-            thread_call_free(fDriverCallEntry);
-            fDriverCallEntry = NULL;
-        }
-        if ( fPMLock ) {
-            IOLockFree(fPMLock);
-            fPMLock = NULL;
-        }
-        if ( fActivityLock ) {
-            IOLockFree(fActivityLock);
-            fActivityLock = NULL;
-        }
-               if ( fInterestedDrivers ) {
+               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 ( fPMWorkQueue ) {
-                       getPMworkloop()->removeEventSource(fPMWorkQueue);
-                       fPMWorkQueue->release();
-                       fPMWorkQueue = 0;
-               }
                if (fDriverCallParamSlots && fDriverCallParamPtr) {
                        IODelete(fDriverCallParamPtr, DriverCallParam, fDriverCallParamSlots);
-                       fDriverCallParamPtr = 0;
+                       fDriverCallParamPtr = NULL;
                        fDriverCallParamSlots = 0;
                }
-        if ( fResponseArray ) {
-            fResponseArray->release();
-            fResponseArray = NULL;
-        }
-        if (fPowerStates && fNumberOfPowerStates) {
-            IODelete(fPowerStates, IOPMPowerState, fNumberOfPowerStates);
-            fNumberOfPowerStates = 0;
-            fPowerStates = NULL;
-        }
+               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)
-               {
+               if (fPMVars) {
                        fPMVars->release();
-                       fPMVars = 0;
+                       fPMVars = NULL;
                }
 #endif
 
-        pwrMgt->release();
-               pwrMgt = 0;
-    }
+               pwrMgt->release();
+               pwrMgt = NULL;
+       }
+}
+
+void
+IOService::PMDebug( uint32_t event, uintptr_t param1, uintptr_t param2 )
+{
+       OUR_PMLog(event, param1, param2);
 }
 
 //*********************************************************************************
-// [public virtual] joinPMtree
+// [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
@@ -536,204 +615,208 @@ void IOService::PMfree ( void )
 // meaning it may not be initialized for power management.
 //*********************************************************************************
 
-void IOService::joinPMtree ( IOService * driver )
+void
+IOService::joinPMtree( IOService * driver )
 {
-    IOPlatformExpert * platform;
+       IOPlatformExpert *  platform;
 
-    platform = getPlatform();
-    assert(platform != 0);
-    platform->PMRegisterDevice(this, driver);
+       platform = getPlatform();
+       assert(platform != NULL);
+       platform->PMRegisterDevice(this, driver);
 }
 
+#ifndef __LP64__
 //*********************************************************************************
-// [public virtual] 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 )
+IOReturn
+IOService::youAreRoot( void )
 {
-    fWeAreRoot = true;
-    fParentsKnowState = true;
-    attachToParent( getRegistryRoot(), gIOPowerPlane );
-    return IOPMNoErr;
+       return IOPMNoErr;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// [public virtual] PMstop
+// [public] PMstop
 //
 // Immediately stop driver callouts. Schedule an async stop request to detach
 // from power plane.
 //*********************************************************************************
 
-void IOService::PMstop ( void )
+void
+IOService::PMstop( void )
 {
        IOPMRequest * request;
 
-       if (!initialized)
+       if (!initialized) {
                return;
-
-       // Schedule an async PMstop request, but immediately stop any further
-       // calls to the controlling or interested drivers. This device will
-       // continue to exist in the power plane and participate in power state
-       // changes until the PMstop async request is processed.
+       }
 
        PM_LOCK();
-       fWillPMStop = true;
-    if (fDriverCallBusy)
-        PM_DEBUG("%s::PMstop() driver call busy\n", getName());
-    PM_UNLOCK();
 
+       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_TRACE("[%s] %p PMstop\n", getName(), this);
+       if (request) {
+               PM_LOG2("%s: %p PMstop\n", getName(), OBFUSCATE(this));
                submitPMRequest( request );
        }
 }
 
 //*********************************************************************************
-// handlePMstop
+// [private] handlePMstop
 //
-// Disconnect the node from its parents and children in the Power Plane.
+// Disconnect the node from all parents and children in the power plane.
 //*********************************************************************************
 
-void IOService::handlePMstop ( IOPMRequest * request )
+void
+IOService::handlePMstop( IOPMRequest * request )
 {
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-    IOService *                        theChild;
-    IOService *                        theParent;
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * connection;
+       IOService *         theChild;
+       IOService *         theParent;
 
        PM_ASSERT_IN_GATE();
-       PM_TRACE("[%s] %p %s start\n", getName(), this, __FUNCTION__);
-
-    // 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_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()))
-               {
+               while ((item = list->firstInList())) {
                        list->removeFromList(item->whatObject);
                }
                PM_UNLOCK();
        }
 
-       // Tell PM_idle_timer_expiration() to ignore idle timer.
+       // Clear idle period to prevent idleTimerExpired() from servicing
+       // idle timer expirations.
+
        fIdleTimerPeriod = 0;
+       if (fIdleTimer && thread_call_cancel(fIdleTimer)) {
+               release();
+       }
 
-       fWillPMStop = false;
-       PM_TRACE("[%s] %p %s done\n", getName(), this, __FUNCTION__);
+       PM_LOG2("%s: %p %s done\n", getName(), OBFUSCATE(this), __FUNCTION__);
 }
 
 //*********************************************************************************
-// [public virtual] addPowerChild
+// [public] addPowerChild
 //
 // Power Management is informing us who our children are.
 //*********************************************************************************
 
-IOReturn IOService::addPowerChild ( IOService * child )
+IOReturn
+IOService::addPowerChild( IOService * child )
 {
-       IOPowerConnection *     connection  = 0;
-       IOPMRequest *           requests[3] = {0, 0, 0};
-    OSIterator *               iter;
-       bool                            ok = true;
+       IOPowerConnection * connection  = NULL;
+       IOPMRequest *       requests[3] = {NULL, NULL, NULL};
+       OSIterator *        iter;
+       bool                ok = true;
 
-       if (!child)
+       if (!child) {
                return kIOReturnBadArgument;
+       }
 
-    if (!initialized || !child->initialized)
+       if (!initialized || !child->initialized) {
                return IOPMNotYetInitialized;
+       }
 
-    OUR_PMLog( kPMLogAddChild, 0, 0 );
+       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;
+               if (iter) {
+                       IORegistryEntry *   entry;
+                       OSObject *          next;
 
-                       while ((next = iter->getNextObject()))
-                       {
+                       while ((next = iter->getNextObject())) {
                                if ((entry = OSDynamicCast(IORegistryEntry, next)) &&
-                                       isChild(entry, gIOPowerPlane))
-                               {
+                                   isChild(entry, gIOPowerPlane)) {
                                        ok = false;
                                        break;
-                               }                       
+                               }
                        }
                        iter->release();
                }
-               if (!ok)
-               {
-                       PM_DEBUG("[%s] %s (%p) is already a child\n",
-                               getName(), child->getName(), child);
+               if (!ok) {
+                       PM_LOG2("%s: %s (%p) is already a child\n",
+                           getName(), child->getName(), OBFUSCATE(child));
                        break;
                }
 
@@ -744,29 +827,31 @@ IOReturn IOService::addPowerChild ( IOService * child )
                // block on the PM work loop.
 
                connection = new IOPowerConnection;
-               if (!connection)
+               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 );
+                       /* target */ this,
+                       /* type */ kIOPMRequestTypeAddPowerChild1 );
 
                requests[1] = acquirePMRequest(
-                                       /* target */ child,
-                                       /* type */   kIOPMRequestTypeAddPowerChild2 );
+                       /* target */ child,
+                       /* type */ kIOPMRequestTypeAddPowerChild2 );
 
                requests[2] = acquirePMRequest(
-                                       /* target */ this,
-                                       /* type */   kIOPMRequestTypeAddPowerChild3 );
+                       /* target */ this,
+                       /* type */ kIOPMRequestTypeAddPowerChild3 );
 
-               if (!requests[0] || !requests[1] || !requests[2])
+               if (!requests[0] || !requests[1] || !requests[2]) {
                        break;
+               }
 
-               requests[0]->setParentRequest( requests[1] );
-               requests[1]->setParentRequest( requests[2] );
+               requests[0]->attachNextRequest( requests[1] );
+               requests[1]->attachNextRequest( requests[2] );
 
                connection->init();
                connection->start(this);
@@ -781,143 +866,147 @@ IOReturn IOService::addPowerChild ( IOService * child )
                requests[1]->fArg0 = connection;
                requests[2]->fArg0 = connection;
 
-               submitPMRequest( requests, 3 );
+               submitPMRequests( requests, 3 );
                return kIOReturnSuccess;
-       }
-       while (false);
+       }while (false);
 
-       if (connection)  connection->release();
-       if (requests[0]) releasePMRequest(requests[0]);
-       if (requests[1]) releasePMRequest(requests[1]);
-       if (requests[2]) releasePMRequest(requests[2]);
+       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
+       // Silent failure, to prevent platform drivers from adding the child
        // to the root domain.
-       return IOPMNoErr;
+
+       return kIOReturnSuccess;
 }
 
 //*********************************************************************************
 // [private] addPowerChild1
 //
-// Called on the power parent.
+// Step 1/3 of adding a power child. Called on the power parent.
 //*********************************************************************************
 
-void IOService::addPowerChild1 ( IOPMRequest * request )
+void
+IOService::addPowerChild1( IOPMRequest * request )
 {
-       unsigned long tempDesire = 0;
+       IOPMPowerStateIndex tempDesire = kPowerStateZero;
 
        // Make us temporary usable before adding the child.
 
        PM_ASSERT_IN_GATE();
-    OUR_PMLog( kPMLogMakeUsable, kPMLogMakeUsable, fDeviceDesire );
+       OUR_PMLog( kPMLogMakeUsable, kPMLogMakeUsable, 0 );
 
-       if (fControllingDriver && inPlane(gIOPowerPlane) && fParentsKnowState)
-       {
-               tempDesire = fNumberOfPowerStates - 1;
+       if (fControllingDriver && inPlane(gIOPowerPlane) && fParentsKnowState) {
+               tempDesire = fHighestPowerState;
        }
 
-       if (tempDesire && (fWeAreRoot || (fMaxCapability >= tempDesire)))
-       {
-               computeDesiredState( tempDesire );
-               changeState();
+       if ((tempDesire != kPowerStateZero) &&
+           (IS_PM_ROOT || (StateOrder(fMaxPowerState) >= StateOrder(tempDesire)))) {
+               adjustPowerState(tempDesire);
        }
 }
 
 //*********************************************************************************
 // [private] addPowerChild2
 //
-// Called on the joining child. Blocked behind addPowerChild1.
+// Step 2/3 of adding a power child. Called on the joining child.
+// Execution blocked behind addPowerChild1.
 //*********************************************************************************
 
-void IOService::addPowerChild2 ( IOPMRequest * request )
+void
+IOService::addPowerChild2( IOPMRequest * request )
 {
        IOPowerConnection * connection = (IOPowerConnection *) request->fArg0;
        IOService *         parent;
-       IOPMPowerFlags          powerFlags;
-       bool                            knowsState;
-       unsigned long           powerState;
-       unsigned long           tempDesire;
+       IOPMPowerFlags      powerFlags;
+       bool                knowsState;
+       unsigned long       powerState;
+       unsigned long       tempDesire;
 
        PM_ASSERT_IN_GATE();
        parent = (IOService *) connection->getParentEntry(gIOPowerPlane);
 
-       if (!parent || !inPlane(gIOPowerPlane))
-       {
-               PM_DEBUG("[%s] addPowerChild2 not in power plane\n", getName());
+       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, safe to
-       // directly access parent's vars.
+       // 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].outputPowerCharacter;
-       else
+       if (knowsState) {
+               powerFlags = parent->fPowerStates[powerState].outputPowerFlags;
+       } else {
                powerFlags = 0;
+       }
 
        // Set our power parent.
 
-    OUR_PMLog(kPMLogSetParent, knowsState, powerFlags);
+       OUR_PMLog(kPMLogSetParent, knowsState, powerFlags);
 
        setParentInfo( powerFlags, connection, knowsState );
 
        connection->setReadyFlag(true);
 
-    if ( fControllingDriver && fParentsKnowState )
-    {
-        fMaxCapability = fControllingDriver->maxCapabilityForDomainState(fParentsCurrentPowerFlags);
-        // initially change into the state we are already in
-        tempDesire = fControllingDriver->initialPowerStateForDomainState(fParentsCurrentPowerFlags);
-        computeDesiredState(tempDesire);
-        fPreviousRequest = 0xffffffff;
-        changeState();
-    }
+       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
 //
-// Called on the parent. Blocked behind addPowerChild2.
+// Step 3/3 of adding a power child. Called on the parent.
+// Execution blocked behind addPowerChild2.
 //*********************************************************************************
 
-void IOService::addPowerChild3 ( IOPMRequest * request )
+void
+IOService::addPowerChild3( IOPMRequest * request )
 {
        IOPowerConnection * connection = (IOPowerConnection *) request->fArg0;
        IOService *         child;
-       unsigned int            i;
+       IOPMrootDomain *    rootDomain = getPMRootDomain();
 
        PM_ASSERT_IN_GATE();
        child = (IOService *) connection->getChildEntry(gIOPowerPlane);
 
-       if (child && inPlane(gIOPowerPlane))
-       {
-               if (child->getProperty("IOPMStrictTreeOrder"))
-               {
-                       PM_DEBUG("[%s] strict ordering enforced\n", getName());
+       if (child && inPlane(gIOPowerPlane)) {
+               if ((this != rootDomain) && child->getProperty("IOPMStrictTreeOrder")) {
+                       PM_LOG1("%s: strict PM order enforced\n", getName());
                        fStrictTreeOrder = true;
                }
 
-               for (i = 0; i <= kMaxType; i++)
-               {
-                       if ( fAggressivenessValid[i] )
-                       {
-                               child->setAggressiveness(i, fAggressivenessValue[i]);
-                       }
+               if (rootDomain) {
+                       rootDomain->joinAggressiveness( child );
                }
-       }
-       else
-       {
-               PM_DEBUG("[%s] addPowerChild3 not in power plane\n", getName());
+       } else {
+               PM_LOG("%s: addPowerChild3 not in power plane\n", getName());
        }
 
        connection->release();
 }
 
+#ifndef __LP64__
 //*********************************************************************************
-// [public virtual deprecated] setPowerParent
+// [deprecated] setPowerParent
 //
 // Power Management is informing us who our parent is.
 // If we have a controlling driver, find out, given our newly-informed
@@ -925,121 +1014,164 @@ void IOService::addPowerChild3 ( IOPMRequest * request )
 // to assume that state.
 //*********************************************************************************
 
-IOReturn IOService::setPowerParent (
+IOReturn
+IOService::setPowerParent(
        IOPowerConnection * theParent, bool stateKnown, IOPMPowerFlags powerFlags )
 {
        return kIOReturnUnsupported;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// [public virtual] removePowerChild
+// [public] removePowerChild
 //
 // Called on a parent whose child is being removed by PMstop().
 //*********************************************************************************
 
-IOReturn IOService::removePowerChild ( IOPowerConnection * theNub )
+IOReturn
+IOService::removePowerChild( IOPowerConnection * theNub )
 {
-    IORegistryEntry *  theChild;
+       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() )
-       {
+       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 )
-               {
+               if (fHeadNotePendingAcks != 0) {
                        // that's one fewer ack to worry about
                        fHeadNotePendingAcks--;
 
                        // is that the last?
-                       if ( fHeadNotePendingAcks == 0 )
-                       {
+                       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();
 
-       // Schedule a request to re-scan child desires and clamp bits.
-       if (!fWillAdjustPowerState)
-       {
-               IOPMRequest * request;
+       // 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)
-               {
+               if (request) {
                        submitPMRequest( request );
-                       fWillAdjustPowerState = true;
+                       fAdjustPowerScheduled = true;
                }
        }
 
-    return IOPMNoErr;
+       return IOPMNoErr;
 }
 
 //*********************************************************************************
-// [public virtual] registerPowerDriver
+// [public] registerPowerDriver
 //
 // A driver has called us volunteering to control power to our device.
 //*********************************************************************************
 
-IOReturn IOService::registerPowerDriver (
-       IOService *                     powerDriver,
-       IOPMPowerState *        powerStates,
-       unsigned long           numberOfStates )
+IOReturn
+IOService::registerPowerDriver(
+       IOService *         powerDriver,
+       IOPMPowerState *    powerStates,
+       unsigned long       numberOfStates )
 {
-       IOPMRequest *    request;
-       IOPMPowerState * powerStatesCopy = 0;
+       IOPMRequest *       request;
+       IOPMPSEntry *       powerStatesCopy = NULL;
+       IOPMPowerStateIndex stateOrder;
+       IOReturn            error = kIOReturnSuccess;
 
-    if (!initialized)
+       if (!initialized) {
                return IOPMNotYetInitialized;
+       }
 
-       // Validate arguments.
-       if (!powerStates || (numberOfStates < 2))
-       {
+       if (!powerStates || (numberOfStates < 2)) {
                OUR_PMLog(kPMLogControllingDriverErr5, numberOfStates, 0);
                return kIOReturnBadArgument;
        }
 
-       if (!powerDriver)
-       {
+       if (!powerDriver || !powerDriver->initialized) {
                OUR_PMLog(kPMLogControllingDriverErr4, 0, 0);
                return kIOReturnBadArgument;
        }
 
-       if (powerStates[0].version != kIOPMPowerStateVersion1)
-       {
+       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(IOPMPowerState, numberOfStates);
-               if (!powerStatesCopy)
+               powerStatesCopy = IONew(IOPMPSEntry, numberOfStates);
+               if (!powerStatesCopy) {
+                       error = kIOReturnNoMemory;
                        break;
+               }
+
+               // Initialize to bogus values
+               for (IOPMPowerStateIndex i = 0; i < numberOfStates; i++) {
+                       powerStatesCopy[i].stateOrderToIndex = kIOPMPowerStateMax;
+               }
 
-               bcopy( powerStates, powerStatesCopy,
-                       sizeof(IOPMPowerState) * numberOfStates );
+               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)
+               if (!request) {
+                       error = kIOReturnNoMemory;
                        break;
+               }
 
                powerDriver->retain();
                request->fArg0 = (void *) powerDriver;
@@ -1048,46 +1180,95 @@ IOReturn IOService::registerPowerDriver (
 
                submitPMRequest( request );
                return kIOReturnSuccess;
+       }while (false);
+
+       if (powerStatesCopy) {
+               IODelete(powerStatesCopy, IOPMPSEntry, numberOfStates);
        }
-       while (false);
 
-       if (powerStatesCopy)
-               IODelete(powerStatesCopy, IOPMPowerState, numberOfStates);
-       return kIOReturnNoMemory;
+       return error;
 }
 
 //*********************************************************************************
 // [private] handleRegisterPowerDriver
 //*********************************************************************************
 
-void IOService::handleRegisterPowerDriver ( IOPMRequest * request )
+void
+IOService::handleRegisterPowerDriver( IOPMRequest * request )
 {
-       IOService *                     powerDriver    = (IOService *)      request->fArg0;
-       IOPMPowerState *        powerStates    = (IOPMPowerState *) request->fArg1;
-       unsigned long           numberOfStates = (unsigned long)    request->fArg2;
-    unsigned long              i;
-       IOService *                     root;
+       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 )
-    {
+       if (!fNumberOfPowerStates) {
                OUR_PMLog(kPMLogControllingDriver,
-                       (unsigned long) numberOfStates,
-                       (unsigned long) powerStates[0].version);
+                   (unsigned long) numberOfStates,
+                   (unsigned long) kIOPMPowerStateVersion1);
 
-        fPowerStates            = powerStates;
+               fPowerStates            = powerStates;
                fNumberOfPowerStates    = numberOfStates;
                fControllingDriver      = powerDriver;
-        fCurrentCapabilityFlags = fPowerStates[0].capabilityFlags;
+               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
 
-               // make a mask of all the character bits we know about
-               fOutputPowerCharacterFlags = 0;
-               for ( i = 0; i < numberOfStates; i++ ) {
-                       fOutputPowerCharacterFlags |= fPowerStates[i].outputPowerCharacter;
+                       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.
@@ -1098,49 +1279,52 @@ void IOService::handleRegisterPowerDriver ( IOPMRequest * request )
                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)
-                       {
+                   ((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();
                        }
                }
 
-               if ( fNeedToBecomeUsable ) {
-                       fNeedToBecomeUsable = false;
-                       fDeviceDesire = fNumberOfPowerStates - 1;
+               // 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 )
-               {
-                       unsigned long tempDesire;
-                       fMaxCapability = fControllingDriver->maxCapabilityForDomainState(fParentsCurrentPowerFlags);
+               if (inPlane(gIOPowerPlane) && fParentsKnowState) {
+                       IOPMPowerStateIndex tempDesire;
+                       fMaxPowerState = fControllingDriver->maxCapabilityForDomainState(fParentsCurrentPowerFlags);
                        // initially change into the state we are already in
                        tempDesire = fControllingDriver->initialPowerStateForDomainState(fParentsCurrentPowerFlags);
-                       computeDesiredState(tempDesire);
-                       changeState();
+                       adjustPowerState(tempDesire);
                }
-       }
-       else
-       {
+       } else {
                OUR_PMLog(kPMLogControllingDriverErr2, numberOfStates, 0);
-        IODelete(powerStates, IOPMPowerState, numberOfStates);
+               IODelete(powerStates, IOPMPSEntry, numberOfStates);
        }
 
        powerDriver->release();
 }
 
 //*********************************************************************************
-// [public virtual] registerInterestedDriver
+// [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
@@ -1148,74 +1332,90 @@ void IOService::handleRegisterPowerDriver ( IOPMRequest * request )
 // out what the current power state of the device is.
 //*********************************************************************************
 
-IOPMPowerFlags IOService::registerInterestedDriver ( IOService * driver )
+IOPMPowerFlags
+IOService::registerInterestedDriver( IOService * driver )
 {
-       IOPMRequest *   request;
-       bool                    signal;
+       IOPMRequest *   request;
+       bool            signal;
 
-       if (!initialized || !fInterestedDrivers)
-               return IOPMNotPowerManaged;
+       if (!driver || !initialized || !fInterestedDrivers) {
+               return 0;
+       }
 
        PM_LOCK();
        signal = (!fInsertInterestSet && !fRemoveInterestSet);
-       if (fInsertInterestSet == NULL)
+       if (fInsertInterestSet == NULL) {
                fInsertInterestSet = OSSet::withCapacity(4);
-       if (fInsertInterestSet)
+       }
+       if (fInsertInterestSet) {
                fInsertInterestSet->setObject(driver);
+               if (fRemoveInterestSet) {
+                       fRemoveInterestSet->removeObject(driver);
+               }
+       }
        PM_UNLOCK();
 
-       if (signal)
-       {
+       if (signal) {
                request = acquirePMRequest( this, kIOPMRequestTypeInterestChanged );
-               if (request)
+               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;  
+       OUR_PMLog(kPMLogInterestedDriver, kIOPMDeviceUsable, 2);
+       return kIOPMDeviceUsable;
 }
 
 //*********************************************************************************
-// [public virtual] deRegisterInterestedDriver
+// [public] deRegisterInterestedDriver
 //*********************************************************************************
 
-IOReturn IOService::deRegisterInterestedDriver ( IOService * driver )
+IOReturn
+IOService::deRegisterInterestedDriver( IOService * driver )
 {
-       IOPMinformeeList *      list;
-    IOPMinformee *             item;
-       IOPMRequest *           request;
-       bool                            signal;
+       IOPMinformee *      item;
+       IOPMRequest *       request;
+       bool                signal;
 
-       if (!initialized || !fInterestedDrivers)
+       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)
+       if (fRemoveInterestSet == NULL) {
                fRemoveInterestSet = OSSet::withCapacity(4);
-       if (fRemoveInterestSet)
-       {
+       }
+       if (fRemoveInterestSet) {
                fRemoveInterestSet->setObject(driver);
-
-               list = fInterestedDrivers;
-               item = list->findItem(driver);
-               if (item && item->active)
-               {
+               if (item->active) {
                        item->active = false;
+                       waitForPMDriverCall( driver );
                }
-               if (fDriverCallBusy)
-            PM_DEBUG("%s::deRegisterInterestedDriver() driver call busy\n", getName());
        }
        PM_UNLOCK();
 
-       if (signal)
-       {
+       if (signal) {
                request = acquirePMRequest( this, kIOPMRequestTypeInterestChanged );
-               if (request)
+               if (request) {
                        submitPMRequest( request );
+               }
        }
 
        return IOPMNoErr;
@@ -1227,39 +1427,32 @@ IOReturn IOService::deRegisterInterestedDriver ( IOService * driver )
 // Handle interest added or removed.
 //*********************************************************************************
 
-void IOService::handleInterestChanged( IOPMRequest * request )
+void
+IOService::handleInterestChanged( IOPMRequest * request )
 {
-       IOService *                     driver;
-    IOPMinformee *             informee;
-       IOPMinformeeList *      list = fInterestedDrivers;
+       IOService *         driver;
+       IOPMinformee *      informee;
+       IOPMinformeeList *  list = fInterestedDrivers;
 
        PM_LOCK();
 
-       if (fInsertInterestSet)
-       {
-               while ((driver = (IOService *) fInsertInterestSet->getAnyObject()))
-               {
-                       if ((list->findItem(driver) == NULL) &&
-                               (!fRemoveInterestSet ||
-                                !fRemoveInterestSet->containsObject(driver)))
-                       {
+       if (fInsertInterestSet) {
+               while ((driver = (IOService *) fInsertInterestSet->getAnyObject())) {
+                       if (list->findItem(driver) == NULL) {
                                informee = list->appendNewInformee(driver);
                        }
                        fInsertInterestSet->removeObject(driver);
                }
                fInsertInterestSet->release();
-               fInsertInterestSet = 0;
+               fInsertInterestSet = NULL;
        }
 
-       if (fRemoveInterestSet)
-       {
-               while ((driver = (IOService *) fRemoveInterestSet->getAnyObject()))
-               {
+       if (fRemoveInterestSet) {
+               while ((driver = (IOService *) fRemoveInterestSet->getAnyObject())) {
                        informee = list->findItem(driver);
-                       if (informee)
-                       {
-                               if (fHeadNotePendingAcks && informee->timer)
-                               {
+                       if (informee) {
+                               // Clean-up async interest acknowledgement
+                               if (fHeadNotePendingAcks && informee->timer) {
                                        informee->timer = 0;
                                        fHeadNotePendingAcks--;
                                }
@@ -1268,14 +1461,14 @@ void IOService::handleInterestChanged( IOPMRequest * request )
                        fRemoveInterestSet->removeObject(driver);
                }
                fRemoveInterestSet->release();
-               fRemoveInterestSet = 0;
+               fRemoveInterestSet = NULL;
        }
 
        PM_UNLOCK();
 }
 
 //*********************************************************************************
-// [public virtual] acknowledgePowerChange
+// [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
@@ -1288,153 +1481,146 @@ void IOService::handleInterestChanged( IOPMRequest * request )
 // of a "current change note".)
 //*********************************************************************************
 
-IOReturn IOService::acknowledgePowerChange ( IOService * whichObject )
+IOReturn
+IOService::acknowledgePowerChange( IOService * whichObject )
 {
        IOPMRequest * request;
 
-    if (!initialized)
+       if (!initialized) {
                return IOPMNotYetInitialized;
-       if (!whichObject)
+       }
+       if (!whichObject) {
                return kIOReturnBadArgument;
+       }
 
        request = acquirePMRequest( this, kIOPMRequestTypeAckPowerChange );
-       if (!request)
-    {
-        PM_ERROR("%s::%s no memory\n", getName(), __FUNCTION__);
+       if (!request) {
                return kIOReturnNoMemory;
-    }
+       }
 
        whichObject->retain();
        request->fArg0 = whichObject;
 
        submitPMRequest( request );
-    return IOPMNoErr;
+       return IOPMNoErr;
 }
 
 //*********************************************************************************
 // [private] handleAcknowledgePowerChange
 //*********************************************************************************
 
-bool IOService::handleAcknowledgePowerChange ( IOPMRequest * request )
+bool
+IOService::handleAcknowledgePowerChange( IOPMRequest * request )
 {
-    IOPMinformee *             informee;
-    unsigned long              childPower = kIOPMUnknown;
-    IOService *                        theChild;
-       IOService *                     whichObject;
-       bool                            all_acked  = false;
+       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?
+       // one of our interested drivers?
        informee = fInterestedDrivers->findItem( whichObject );
-    if ( informee == NULL )
-    {
-        if ( !isChild(whichObject, gIOPowerPlane) )
-        {
+       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 LOG_SETPOWER_TIMES
-                if (informee->timer > 0)
-                {
-                    uint64_t nsec = computeTimeDeltaNS(&informee->startTime);
-                    if (nsec > LOG_SETPOWER_TIMES)
-                        PM_DEBUG("%s::powerState%sChangeTo(%p, %s, %lu -> %lu) async took %d ms\n",
-                            informee->whatObject->getName(),
-                            (fDriverCallReason == kDriverCallInformPreChange) ? "Will" : "Did",
-                            informee->whatObject,
-                            fName, fCurrentPowerState, fHeadNoteState, NS_TO_MS(nsec));
-                }
-#endif
-                // 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 )
-                {
-                    fPowerStates[fHeadNoteState].staticPower = kIOPMUnknown;
-                } else {
-                    if ( fPowerStates[fHeadNoteState].staticPower != kIOPMUnknown )
-                    {
-                        fPowerStates[fHeadNoteState].staticPower += childPower;
-                    }
-                }
-            }
-           }
-
-               if ( fHeadNotePendingAcks == 0 ) {
-                       // yes, stop the timer
-                       stop_ack_timer();
-                       // and now we can continue
-                       all_acked = true;
+               } else {
+                       OUR_PMLog(kPMLogChildAcknowledge, fHeadNotePendingAcks, 0);
                }
-    } else {
-        OUR_PMLog(kPMLogAcknowledgeErr3, 0, 0);        // not expecting anybody to ack
-    }
+       } 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)
+       if (whichObject) {
                whichObject->release();
+       }
 
-    return all_acked;
+       return all_acked;
 }
 
 //*********************************************************************************
-// [public virtual] acknowledgeSetPowerState
+// [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 )
+IOReturn
+IOService::acknowledgeSetPowerState( void )
 {
        IOPMRequest * request;
 
-    if (!initialized)
+       if (!initialized) {
                return IOPMNotYetInitialized;
+       }
 
        request = acquirePMRequest( this, kIOPMRequestTypeAckSetPowerState );
-       if (!request)
-       {
-        PM_ERROR("%s::%s no memory\n", getName(), __FUNCTION__);
+       if (!request) {
                return kIOReturnNoMemory;
        }
 
@@ -1444,31 +1630,121 @@ IOReturn IOService::acknowledgeSetPowerState ( void )
 
 //*********************************************************************************
 // [private] adjustPowerState
-//
-// Child has signaled a change - child changed it's desire, new child added,
-// existing child removed. Adjust our power state accordingly.
 //*********************************************************************************
 
-void IOService::adjustPowerState( void )
+void
+IOService::adjustPowerState( uint32_t clamp )
 {
        PM_ASSERT_IN_GATE();
-       if (inPlane(gIOPowerPlane))
-       {
-               rebuildChildClampBits();
-               computeDesiredState();
-               if ( fControllingDriver && fParentsKnowState )
-                       changeState();
+       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);
        }
-       else
-       {
-               PM_DEBUG("[%s] %s: not in power tree\n", getName(), __FUNCTION__);
-               return;
+}
+
+//*********************************************************************************
+// [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);
        }
-       fWillAdjustPowerState = false;
 }
 
+#ifndef __LP64__
 //*********************************************************************************
-// [public deprecated] powerDomainWillChangeTo
+// [deprecated] powerDomainWillChangeTo
 //
 // Called by the power-hierarchy parent notifying of a new power state
 // in the power domain.
@@ -1477,117 +1753,124 @@ void IOService::adjustPowerState( void )
 // kind of change is occuring in the domain.
 //*********************************************************************************
 
-IOReturn IOService::powerDomainWillChangeTo (
-       IOPMPowerFlags          newPowerFlags,
-       IOPowerConnection *     whichParent )
+IOReturn
+IOService::powerDomainWillChangeTo(
+       IOPMPowerFlags      newPowerFlags,
+       IOPowerConnection * whichParent )
 {
        assert(false);
        return kIOReturnUnsupported;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
 // [private] handlePowerDomainWillChangeTo
 //*********************************************************************************
 
-void IOService::handlePowerDomainWillChangeTo ( IOPMRequest * request )
-{
-       IOPMPowerFlags          newPowerFlags = (IOPMPowerFlags)      request->fArg0;
-       IOPowerConnection *     whichParent   = (IOPowerConnection *) request->fArg1;
-       bool                            powerWillDrop = (bool)                request->fArg2;
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-    unsigned long              newPowerState;
-    IOPMPowerFlags             combinedPowerFlags;
-       bool                            savedParentsKnowState;
-       IOReturn                        result = IOPMAckImplied;
+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, newPowerFlags, 0);
+       OUR_PMLog(kPMLogWillChange, parentPowerFlags, 0);
 
-       if (!inPlane(gIOPowerPlane) || !whichParent || !whichParent->getAwaitingAck())
-       {
-               PM_DEBUG("[%s] %s: not in power tree\n", getName(), __FUNCTION__);
-        goto exit_no_ack;
+       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' power flags to determine our maximum state
-       // within the new power domain
+       // 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 |= newPowerFlags;
-                else
-                    combinedPowerFlags |= connection->parentCurrentPowerFlags();
-            }
-        }
-        iter->release();
-    }
-
-    if  ( fControllingDriver )
-    {
-               newPowerState = fControllingDriver->maxCapabilityForDomainState(
-                                                       combinedPowerFlags);
-
-               result = enqueuePowerChange(
-                 /* flags        */    IOPMParentInitiated | IOPMDomainWillChange,
-                 /* power state  */    newPowerState,
-                                /* domain state */     combinedPowerFlags,
-                                /* connection   */     whichParent,
-                                /* parent state */     newPowerFlags);
+       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 (powerWillDrop)
-       {
-               setParentInfo(newPowerFlags, whichParent, true);
+       if (parentChangeFlags & kIOPMDomainPowerDrop) {
+               setParentInfo(parentPowerFlags, whichParent, true);
        }
 
        // Parent is expecting an ACK from us. If we did not embark on a state
-       // transition, when enqueuePowerChang() returns IOPMAckImplied. We are
+       // transition, i.e. startPowerChange() returned IOPMAckImplied. We are
        // still required to issue an ACK to our parent.
 
-       if (IOPMAckImplied == result)
-       {
+       if (IOPMAckImplied == result) {
                IOService * parent;
                parent = (IOService *) whichParent->copyParentEntry(gIOPowerPlane);
                assert(parent);
-               if ( parent )
-               {
+               if (parent) {
                        parent->acknowledgePowerChange( whichParent );
                        parent->release();
                }
        }
 
-       // If the parent registers it's power driver late, then this is the
-       // first opportunity to tell our parent about our desire. 
-
-       if (!savedParentsKnowState && fParentsKnowState)
-       {
-               PM_TRACE("[%s] powerDomainWillChangeTo: parentsKnowState = true\n",
-                       getName());
-               ask_parent( fDesiredPowerState );
-       }
-
 exit_no_ack:
-    // Drop the retain from notifyChild().
-    if (whichParent) whichParent->release();
+       // Drop the retain from notifyChild().
+       if (whichParent) {
+               whichParent->release();
+       }
 }
 
+#ifndef __LP64__
 //*********************************************************************************
-// [public deprecated] powerDomainDidChangeTo
+// [deprecated] powerDomainDidChangeTo
 //
 // Called by the power-hierarchy parent after the power state of the power domain
 // has settled at a new level.
@@ -1596,81 +1879,146 @@ exit_no_ack:
 // kind of change is occuring in the domain.
 //*********************************************************************************
 
-IOReturn IOService::powerDomainDidChangeTo (
-       IOPMPowerFlags          newPowerFlags,
-       IOPowerConnection *     whichParent )
+IOReturn
+IOService::powerDomainDidChangeTo(
+       IOPMPowerFlags      newPowerFlags,
+       IOPowerConnection * whichParent )
 {
        assert(false);
        return kIOReturnUnsupported;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
 // [private] handlePowerDomainDidChangeTo
 //*********************************************************************************
 
-void IOService::handlePowerDomainDidChangeTo ( IOPMRequest * request )
-{
-       IOPMPowerFlags          newPowerFlags = (IOPMPowerFlags)      request->fArg0;
-       IOPowerConnection *     whichParent   = (IOPowerConnection *) request->fArg1;
-    unsigned long              newPowerState;
-       bool                            savedParentsKnowState;
-       IOReturn                        result = IOPMAckImplied;
+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, newPowerFlags, 0);
+       OUR_PMLog(kPMLogDidChange, parentPowerFlags, 0);
 
-       if (!inPlane(gIOPowerPlane) || !whichParent || !whichParent->getAwaitingAck())
-       {
-               PM_DEBUG("[%s] %s: not in power tree\n", getName(), __FUNCTION__);
-        goto exit_no_ack;
+       if (!inPlane(gIOPowerPlane) || !whichParent || !whichParent->getAwaitingAck()) {
+               PM_LOG("%s::%s not in power tree\n", getName(), __FUNCTION__);
+               goto exit_no_ack;
        }
 
        savedParentsKnowState = fParentsKnowState;
 
-    setParentInfo(newPowerFlags, whichParent, true);
+       setParentInfo(parentPowerFlags, whichParent, true);
 
-    if ( fControllingDriver )
-       {
-               newPowerState = fControllingDriver->maxCapabilityForDomainState(
-                                                       fParentsCurrentPowerFlags);
+       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;
+                               }
+                       }
+               }
 
-               result = enqueuePowerChange(
-                                /* flags        */     IOPMParentInitiated | IOPMDomainDidChange,
-                 /* power state  */    newPowerState,
-                                /* domain state */     fParentsCurrentPowerFlags,
-                                /* connection   */     whichParent,
-                                /* parent state */     0);
+               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, when enqueuePowerChang() returns IOPMAckImplied. We are
+       // transition, i.e. startPowerChange() returned IOPMAckImplied. We are
        // still required to issue an ACK to our parent.
 
-       if (IOPMAckImplied == result)
-       {
+       if (IOPMAckImplied == result) {
                IOService * parent;
                parent = (IOService *) whichParent->copyParentEntry(gIOPowerPlane);
                assert(parent);
-               if ( parent )
-               {
+               if (parent) {
                        parent->acknowledgePowerChange( whichParent );
                        parent->release();
                }
        }
 
-       // If the parent registers it's power driver late, then this is the
-       // first opportunity to tell our parent about our desire. 
+       // 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 (!savedParentsKnowState && fParentsKnowState)
-       {
-               PM_TRACE("[%s] powerDomainDidChangeTo: parentsKnowState = true\n",
-                       getName());
-               ask_parent( fDesiredPowerState );
+       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();
+       // Drop the retain from notifyChild().
+       if (whichParent) {
+               whichParent->release();
+       }
 }
 
 //*********************************************************************************
@@ -1679,264 +2027,228 @@ exit_no_ack:
 // Set our connection data for one specific parent, and then combine all the parent
 // data together.
 //*********************************************************************************
-void IOService::setParentInfo (
-       IOPMPowerFlags          newPowerFlags,
+
+void
+IOService::setParentInfo(
+       IOPMPowerFlags      newPowerFlags,
        IOPowerConnection * whichParent,
-       bool                            knowsState )
+       bool                knowsState )
 {
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        conn;
+       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();
-    }
-}
-
-//*********************************************************************************
-// [private] rebuildChildClampBits
-//
-// The ChildClamp bits (kIOPMChildClamp & kIOPMChildClamp2) in our capabilityFlags
-// indicate that one of our children (or grandchildren or great-grandchildren ...)
-// 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;
-       unsigned long           powerState;
-
-    // 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 < fNumberOfPowerStates; i++ )
-    {
-        fPowerStates[i].capabilityFlags &= ~(kIOPMChildClamp | kIOPMChildClamp2);
-    }
-
-    // Loop through the children. When we encounter the calling child, save the
-       // computed state as this child's desire. And set the ChildClamp bits in any
-    // of our states that some child has clamp on.
-
-    iter = getChildIterator(gIOPowerPlane);
-    if ( iter )
-    {
-        while ( (next = iter->getNextObject()) )
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection, next)) )
-            {
-                               if (connection->getReadyFlag() == false)
-                               {
-                                       PM_CONNECT("[%s] %s: connection not ready\n",
-                                               getName(), __FUNCTION__);
-                                       continue;
-                               }
+       // 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();
+       }
+}
+
+//******************************************************************************
+// [private] trackSystemSleepPreventers
+//******************************************************************************
+
+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
+       }
 
-                               powerState = connection->getDesiredDomainState();
-                if (powerState < fNumberOfPowerStates)
-                {
-                    if ( connection->getPreventIdleSleepFlag() )
-                        fPowerStates[powerState].capabilityFlags |= kIOPMChildClamp;
-                    if ( connection->getPreventSystemSleepFlag() )
-                        fPowerStates[powerState].capabilityFlags |= kIOPMChildClamp2;
-                }
-            }
-        }
-        iter->release();
-    }
+       if ((oldCapability ^ newCapability) & kIOPMPreventSystemSleep) {
+               getPMRootDomain()->updatePreventSystemSleepList(this,
+                   ((oldCapability & kIOPMPreventSystemSleep) == 0));
+       }
 }
 
 //*********************************************************************************
-// [public virtual] requestPowerDomainState
+// [public] requestPowerDomainState
 //
-// The child of a power domain calls it parent here to request power of a certain
-// character.
+// Called on a power parent when a child's power requirement changes.
 //*********************************************************************************
 
-IOReturn IOService::requestPowerDomainState (
-       IOPMPowerFlags          desiredState,
-       IOPowerConnection *     whichChild,
-       unsigned long           specification )
+IOReturn
+IOService::requestPowerDomainState(
+       IOPMPowerFlags      childRequestPowerFlags,
+       IOPowerConnection * childConnection,
+       unsigned long       specification )
 {
-    unsigned long              i;
-    unsigned long              computedState;
-    unsigned long              theDesiredState;
-       IOService *                     child;
-       IOPMRequest *           childRequest;
+       IOPMPowerStateIndex order, powerState;
+       IOPMPowerFlags      outputPowerFlags;
+       IOService *         child;
+       IOPMRequest *       subRequest;
+       bool                adjustPower = false;
 
-    if (!initialized)
+       if (!initialized) {
                return IOPMNotYetInitialized;
+       }
 
-       if (gIOPMWorkLoop->onThread() == false)
-       {
-               PM_DEBUG("[%s] called requestPowerDomainState\n", getName());
+       if (gIOPMWorkLoop->onThread() == false) {
+               PM_LOG("%s::requestPowerDomainState\n", getName());
                return kIOReturnSuccess;
        }
 
-       theDesiredState = desiredState & ~(kIOPMPreventIdleSleep | kIOPMPreventSystemSleep);
-
-    OUR_PMLog(kPMLogRequestDomain, desiredState, specification);
+       OUR_PMLog(kPMLogRequestDomain, childRequestPowerFlags, specification);
 
-       if (!isChild(whichChild, gIOPowerPlane))
+       if (!isChild(childConnection, gIOPowerPlane)) {
                return kIOReturnNotAttached;
+       }
 
-    if (fControllingDriver == NULL || !fPowerStates)
-        return IOPMNotYetInitialized;
+       if (!fControllingDriver || !fNumberOfPowerStates) {
+               return kIOReturnNotReady;
+       }
 
-       child = (IOService *) whichChild->getChildEntry(gIOPowerPlane);
+       child = (IOService *) childConnection->getChildEntry(gIOPowerPlane);
        assert(child);
 
-    switch (specification) {
-        case IOPMLowestState:
-            i = 0;
-            while ( i < fNumberOfPowerStates )
-            {
-                if ( ( fPowerStates[i].outputPowerCharacter & theDesiredState) ==
-                                        (theDesiredState & fOutputPowerCharacterFlags) )
-                {
-                    break;
-                }
-                i++;
-            }
-            if ( i >= fNumberOfPowerStates )
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        case IOPMNextLowerState:
-            i = fCurrentPowerState - 1;
-            while ( (int) i >= 0 )
-            {
-                if ( ( fPowerStates[i].outputPowerCharacter & theDesiredState) ==
-                                        (theDesiredState & fOutputPowerCharacterFlags) )
-                {
-                    break;
-                }
-                i--;
-            }
-            if ( (int) i < 0 )
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        case IOPMHighestState:
-            i = fNumberOfPowerStates;
-            while ( (int) i >= 0 )
-            {
-                i--;
-                if ( ( fPowerStates[i].outputPowerCharacter & theDesiredState) ==
-                                        (theDesiredState & fOutputPowerCharacterFlags) )
-                {
-                    break;
-                }
-            }
-            if ( (int) i < 0 )
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        case IOPMNextHigherState:
-            i = fCurrentPowerState + 1;
-            while ( i < fNumberOfPowerStates )
-            {
-                if ( ( fPowerStates[i].outputPowerCharacter & theDesiredState) ==
-                                        (theDesiredState & fOutputPowerCharacterFlags) )
-                {
-                    break;
-                }
-                i++;
-            }
-            if ( i == fNumberOfPowerStates )
-            {
-                return IOPMNoSuchState;
-            }
-            break;
-
-        default:
-            return IOPMBadSpecification;
-    }
-
-    computedState = i;
-
-       // Clamp removed on the initial power request from a new child.
-
-       if (fClampOn && !whichChild->childHasRequestedPower())
-       {
-               PM_TRACE("[%s] %p power clamp removed (child = %p)\n",
-                       getName(), this, whichChild);
-               fClampOn = false;
-               fDeviceDesire = 0;
+       // 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;
 
-       // Record the child's desires on the connection.
-#if SUPPORT_IDLE_CANCEL
-       bool attemptCancel = ((kIOPMPreventIdleSleep & desiredState) && !whichChild->getPreventIdleSleepFlag());
-#endif
-       whichChild->setDesiredDomainState( computedState );
-       whichChild->setPreventIdleSleepFlag( desiredState & kIOPMPreventIdleSleep );
-       whichChild->setPreventSystemSleepFlag( desiredState & kIOPMPreventSystemSleep );
-       whichChild->setChildHasRequestedPower();
+       // Map child's requested power flags to one of our power state.
 
-       if (whichChild->getReadyFlag() == false)
-               return IOPMNoErr;
+       for (order = 0; order < fNumberOfPowerStates; order++) {
+               powerState = fPowerStates[order].stateOrderToIndex;
+               if ((fPowerStates[powerState].outputPowerFlags & childRequestPowerFlags)
+                   == childRequestPowerFlags) {
+                       break;
+               }
+       }
+       if (order >= fNumberOfPowerStates) {
+               powerState = kPowerStateZero;
+       }
 
-       // Issue a ping for us to re-evaluate all children desires and
-       // possibly change power state.
+       // 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 (!fWillAdjustPowerState && !fDeviceOverrides)
-       {
-               childRequest = acquirePMRequest( this, kIOPMRequestTypeAdjustPowerState );
-               if (childRequest)
-               {
-                       submitPMRequest( childRequest );
-                       fWillAdjustPowerState = true;
-               }
+       if (!childConnection->childHasRequestedPower() ||
+           (powerState != childConnection->getDesiredDomainState())) {
+               adjustPower = true;
        }
-#if SUPPORT_IDLE_CANCEL
-       if (attemptCancel)
-       {
-               childRequest = acquirePMRequest( this, kIOPMRequestTypeIdleCancel );
-               if (childRequest)
-               {
-                       submitPMRequest( childRequest );
-               }
+
+#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
 
-       return IOPMNoErr;
+       // 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 virtual] temporaryPowerClampOn
+// [public] temporaryPowerClampOn
 //
 // A power domain wants to clamp its power on till it has children which
 // will thendetermine the power domain state.
@@ -1944,23 +2256,14 @@ IOReturn IOService::requestPowerDomainState (
 // We enter the highest state until addPowerChild is called.
 //*********************************************************************************
 
-IOReturn IOService::temporaryPowerClampOn ( void )
+IOReturn
+IOService::temporaryPowerClampOn( void )
 {
-       IOPMRequest * request;
-
-    if (!initialized)
-               return IOPMNotYetInitialized;
-
-       request = acquirePMRequest( this, kIOPMRequestTypeTemporaryPowerClamp );
-       if (!request)
-               return kIOReturnNoMemory;
-
-       submitPMRequest( request );
-    return IOPMNoErr;
+       return requestPowerState( gIOPMPowerClientChildProxy, kIOPMPowerStateMax );
 }
 
 //*********************************************************************************
-// [public virtual] makeUsable
+// [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
@@ -1971,1832 +2274,2955 @@ IOReturn IOService::temporaryPowerClampOn ( void )
 // highest power state.
 //*********************************************************************************
 
-IOReturn IOService::makeUsable ( void )
+IOReturn
+IOService::makeUsable( void )
 {
-       IOPMRequest * request;
-
-    if (!initialized)
-               return IOPMNotYetInitialized;
+       OUR_PMLog(kPMLogMakeUsable, 0, 0);
+       return requestPowerState( gIOPMPowerClientDevice, kIOPMPowerStateMax );
+}
 
-    OUR_PMLog(kPMLogMakeUsable, 0, 0);
+//*********************************************************************************
+// [public] currentCapability
+//*********************************************************************************
 
-       request = acquirePMRequest( this, kIOPMRequestTypeMakeUsable );
-       if (!request)
-               return kIOReturnNoMemory;
+IOPMPowerFlags
+IOService::currentCapability( void )
+{
+       if (!initialized) {
+               return IOPMNotPowerManaged;
+       }
 
-       submitPMRequest( request );
-    return IOPMNoErr;
+       return fCurrentCapabilityFlags;
 }
 
 //*********************************************************************************
-// [private] handleMakeUsable
+// [public] changePowerStateTo
 //
-// Handle a request to become usable.
+// 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.
 //*********************************************************************************
 
-void IOService::handleMakeUsable ( IOPMRequest * request )
+IOReturn
+IOService::changePowerStateTo( unsigned long ordinal )
 {
-       PM_ASSERT_IN_GATE();
-    if ( fControllingDriver )
-    {
-               fDeviceDesire = fNumberOfPowerStates - 1;
-               computeDesiredState();
-               if ( inPlane(gIOPowerPlane) && fParentsKnowState )
-               {
-                       changeState();
-               }
-       }
-       else
-       {
-        fNeedToBecomeUsable = true;
-    }
+       OUR_PMLog(kPMLogChangeStateTo, ordinal, 0);
+       return requestPowerState( gIOPMPowerClientDriver, ordinal );
 }
 
 //*********************************************************************************
-// [public virtual] currentCapability
+// [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.
 //*********************************************************************************
 
-IOPMPowerFlags IOService::currentCapability ( void )
+IOReturn
+IOService::changePowerStateToPriv( unsigned long ordinal )
 {
-       if (!initialized)
-               return IOPMNotPowerManaged;
-
-    return fCurrentCapabilityFlags;
+       OUR_PMLog(kPMLogChangeStateToPriv, ordinal, 0);
+       return requestPowerState( gIOPMPowerClientDevice, ordinal );
 }
 
 //*********************************************************************************
-// [public virtual] changePowerStateTo
+// [public] changePowerStateWithOverrideTo
 //
-// 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.
+// 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::changePowerStateTo ( unsigned long ordinal )
+IOReturn
+IOService::changePowerStateWithOverrideTo( IOPMPowerStateIndex ordinal,
+    IOPMRequestTag tag )
 {
        IOPMRequest * request;
 
-       if (!initialized)
-               return IOPMNotYetInitialized;
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
+       }
 
-    OUR_PMLog(kPMLogChangeStateTo, ordinal, 0);
+       OUR_PMLog(kPMLogChangeStateToPriv, ordinal, 0);
 
-       request = acquirePMRequest( this, kIOPMRequestTypeChangePowerStateTo );
-       if (!request)
+       request = acquirePMRequest( this, kIOPMRequestTypeRequestPowerStateOverride );
+       if (!request) {
                return kIOReturnNoMemory;
+       }
 
+       gIOPMPowerClientDevice->retain();
+       request->fRequestTag = tag;
        request->fArg0 = (void *) ordinal;
-       request->fArg1 = (void *) false;
+       request->fArg1 = (void *) gIOPMPowerClientDevice;
+       request->fArg2 = NULL;
+#if NOT_READY
+       if (action) {
+               request->installCompletionAction( action, target, param );
+       }
+#endif
 
-       // Avoid needless downwards power transitions by clamping power in
-       // computeDesiredState() until the delayed request is processed.
+       // Prevent needless downwards power transitions by clamping power
+       // until the scheduled request is executed.
 
-       if (gIOPMWorkLoop->inGate())
-       {
-               fTempClampPowerState = max(fTempClampPowerState, ordinal);
+       if (gIOPMWorkLoop->inGate() && (ordinal < fNumberOfPowerStates)) {
+               fTempClampPowerState = StateMax(fTempClampPowerState, ordinal);
                fTempClampCount++;
-               request->fArg1 = (void *) true;
+               fOverrideMaxPowerState = ordinal;
+               request->fArg2 = (void *) (uintptr_t) true;
        }
 
        submitPMRequest( request );
-    return IOPMNoErr;
+       return IOPMNoErr;
 }
 
 //*********************************************************************************
-// [private] handleChangePowerStateTo
+// [public] changePowerStateForRootDomain
+//
+// Adjust the root domain's power desire on the target
 //*********************************************************************************
 
-void IOService::handleChangePowerStateTo ( IOPMRequest * request )
+IOReturn
+IOService::changePowerStateForRootDomain( IOPMPowerStateIndex ordinal )
 {
-       unsigned long ordinal = (unsigned long) request->fArg0;
-
-       PM_ASSERT_IN_GATE();
-       if (request->fArg1)
-       {
-               assert(fTempClampCount != 0);
-               if (fTempClampCount)
-                       fTempClampCount--;
-               if (!fTempClampCount)
-                       fTempClampPowerState = 0;
-       }
-
-       if ( fControllingDriver && (ordinal < fNumberOfPowerStates))
-    {
-               fDriverDesire = ordinal;
-               computeDesiredState();
-               if ( inPlane(gIOPowerPlane) && fParentsKnowState )
-               {
-                       changeState();
-               }
-       }
+       OUR_PMLog(kPMLogChangeStateForRootDomain, ordinal, 0);
+       return requestPowerState( gIOPMPowerClientRootDomain, ordinal );
 }
 
 //*********************************************************************************
-// [public virtual] changePowerStateToPriv
+// [public for PMRD] quiescePowerTree
 //
-// 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.
+// For root domain to issue a request to quiesce the power tree.
+// Supplied callback invoked upon completion.
 //*********************************************************************************
 
-IOReturn IOService::changePowerStateToPriv ( unsigned long ordinal )
+IOReturn
+IOService::quiescePowerTree(
+       void * target, IOPMCompletionAction action, void * param )
 {
        IOPMRequest * request;
 
-       if (!initialized)
-               return IOPMNotYetInitialized;
-
-       request = acquirePMRequest( this, kIOPMRequestTypeChangePowerStateToPriv );
-       if (!request)
-               return kIOReturnNoMemory;
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
+       }
+       if (!target || !action) {
+               return kIOReturnBadArgument;
+       }
 
-       request->fArg0 = (void *) ordinal;
-       request->fArg1 = (void *) false;
+       OUR_PMLog(kPMLogQuiescePowerTree, 0, 0);
 
-       // Avoid needless downwards power transitions by clamping power in
-       // computeDesiredState() until the delayed request is processed.
+       // 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.
 
-       if (gIOPMWorkLoop->inGate())
-       {
-               fTempClampPowerState = max(fTempClampPowerState, ordinal);
-               fTempClampCount++;
-               request->fArg1 = (void *) true;
+       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 IOPMNoErr;
+       return kIOReturnSuccess;
 }
 
 //*********************************************************************************
-// [private] handleChangePowerStateToPriv
+// [private] requestPowerState
 //*********************************************************************************
 
-void IOService::handleChangePowerStateToPriv ( IOPMRequest * request )
+IOReturn
+IOService::requestPowerState(
+       const OSSymbol *      client,
+       uint32_t              state )
 {
-       unsigned long ordinal = (unsigned long) request->fArg0;
+       IOPMRequest * request;
 
-       PM_ASSERT_IN_GATE();
-    OUR_PMLog(kPMLogChangeStateToPriv, ordinal, 0);
-       if (request->fArg1)
-       {
-               assert(fTempClampCount != 0);
-               if (fTempClampCount)
-                       fTempClampCount--;
-               if (!fTempClampCount)
-                       fTempClampPowerState = 0;
+       if (!client) {
+               return kIOReturnBadArgument;
        }
-
-       if ( fControllingDriver && (ordinal < fNumberOfPowerStates))
-       {
-               fDeviceDesire = ordinal;
-               computeDesiredState();
-               if ( inPlane(gIOPowerPlane) && fParentsKnowState )
-               {
-                       changeState();
-               }
+       if (!initialized) {
+               return kIOPMNotYetInitialized;
        }
-}
 
-//*********************************************************************************
-// [private] computeDesiredState
-//*********************************************************************************
+       request = acquirePMRequest( this, kIOPMRequestTypeRequestPowerState );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
 
-void IOService::computeDesiredState ( unsigned long tempDesire )
-{
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-    unsigned long              newDesiredState = 0;
-       unsigned long           childDesire = 0;
-       unsigned long           deviceDesire;
-
-       if (tempDesire)
-               deviceDesire = tempDesire;
-       else
-               deviceDesire = fDeviceDesire;
-
-       // If clamp is on, always override deviceDesire to max.
-
-       if (fClampOn && fNumberOfPowerStates)
-               deviceDesire = fNumberOfPowerStates - 1;
-
-    // Compute the maximum  of our children's desires,
-       // our controlling driver's desire, and the subclass device's desire.
-
-    if ( !fDeviceOverrides )
-    {
-        iter = getChildIterator(gIOPowerPlane);
-        if ( iter )
-        {
-            while ( (next = iter->getNextObject()) )
-            {
-                if ( (connection = OSDynamicCast(IOPowerConnection, next)) )
-                {
-                                       if (connection->getReadyFlag() == false)
-                                       {
-                                               PM_CONNECT("[%s] %s: connection not ready\n",
-                                                       getName(), __FUNCTION__);
-                                               continue;
-                                       }
-       
-                    if (connection->getDesiredDomainState() > childDesire)
-                        childDesire = connection->getDesiredDomainState();
-                }
-            }
-            iter->release();
-        }
-
-        fChildrenDesire = childDesire;
-               newDesiredState = max(childDesire, fDriverDesire);
-    }
-
-       newDesiredState = max(deviceDesire, newDesiredState);
-       if (fTempClampCount && (fTempClampPowerState < fNumberOfPowerStates))
-               newDesiredState = max(fTempClampPowerState, newDesiredState);
-
-    fDesiredPowerState = newDesiredState;
-    
-    // Limit check against number of power states.
-
-    if (fNumberOfPowerStates == 0)
-        fDesiredPowerState = 0;
-    else if (fDesiredPowerState >= fNumberOfPowerStates)
-        fDesiredPowerState = fNumberOfPowerStates - 1;
-
-       // Restart idle timer if stopped and deviceDesire has increased.
-
-       if (fDeviceDesire && fActivityTimerStopped)
-       {
-               fActivityTimerStopped = false;
-               start_PM_idle_timer();
+       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
 
-       // Invalidate cached tickle power state when desires change, and not
-       // due to a tickle request.  This invalidation must occur before the
-       // power state change to minimize races.  We want to err on the side
-       // of servicing more activity tickles rather than dropping one when
-       // the device is in a low power state.
+       // Prevent needless downwards power transitions by clamping power
+       // until the scheduled request is executed.
 
-       if (fPMRequest && (fPMRequest->getType() != kIOPMRequestTypeActivityTickle) &&
-               (fActivityTicklePowerState != -1))
-       {
-               IOLockLock(fActivityLock);
-               fActivityTicklePowerState = -1;
-               IOLockUnlock(fActivityLock);
+       if (gIOPMWorkLoop->inGate() && (state < fNumberOfPowerStates)) {
+               fTempClampPowerState = StateMax(fTempClampPowerState, state);
+               fTempClampCount++;
+               request->fArg2 = (void *) (uintptr_t) true;
        }
 
-       PM_TRACE("   NewState %ld, Child %ld, Driver %ld, Device %ld, Clamp %d (%ld)\n",
-               fDesiredPowerState, childDesire, fDriverDesire, deviceDesire,
-               fClampOn, fTempClampCount ? fTempClampPowerState : 0);
+       submitPMRequest( request );
+       return IOPMNoErr;
 }
 
 //*********************************************************************************
-// [private] changeState
-//
-// 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).
+// [private] handleRequestPowerState
 //*********************************************************************************
 
-IOReturn IOService::changeState ( void )
+void
+IOService::handleRequestPowerState( IOPMRequest * request )
 {
-       IOReturn result;
+       const OSSymbol * client = (const OSSymbol *)    request->fArg1;
+       uint32_t         state  = (uint32_t)(uintptr_t) request->fArg0;
 
        PM_ASSERT_IN_GATE();
-       assert(inPlane(gIOPowerPlane));
-       assert(fParentsKnowState);
-       assert(fControllingDriver);
+       if (request->fArg2) {
+               assert(fTempClampCount != 0);
+               if (fTempClampCount) {
+                       fTempClampCount--;
+               }
+               if (!fTempClampCount) {
+                       fTempClampPowerState = kPowerStateZero;
+               }
+       }
 
-       result = enqueuePowerChange(
-                        /* flags        */     IOPMWeInitiated,
-                        /* power state  */     fDesiredPowerState,
-                        /* domain state */     0,
-                        /* connection   */     0,
-                        /* parent state */     0);
+       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;
+       }
 
-       return result;
+       if ((state == kPowerStateZero) &&
+           (client != gIOPMPowerClientDevice) &&
+           (client != gIOPMPowerClientDriver) &&
+           (client != gIOPMPowerClientChildProxy)) {
+               removePowerClient(client);
+       } else {
+               updatePowerClient(client, state);
+       }
+
+       adjustPowerState();
+       client->release();
 }
 
 //*********************************************************************************
-// [public virtual] currentPowerConsumption
-//
+// [private] Helper functions to update/remove power clients.
 //*********************************************************************************
 
-unsigned long IOService::currentPowerConsumption ( void )
+void
+IOService::updatePowerClient( const OSSymbol * client, uint32_t powerState )
 {
-    if (!initialized)
-        return kIOPMUnknown;
+       IOPMPowerStateIndex oldPowerState = kPowerStateZero;
 
-    return fCurrentPowerConsumption;
+       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);
+       }
 }
 
-//*********************************************************************************
-// [public virtual] getPMworkloop
-//*********************************************************************************
+void
+IOService::removePowerClient( const OSSymbol * client )
+{
+       if (fPowerClients && client) {
+               fPowerClients->removeObject(client);
+       }
+}
 
-IOWorkLoop * IOService::getPMworkloop ( void )
+uint32_t
+IOService::getPowerStateForClient( const OSSymbol * client )
 {
-       return gIOPMWorkLoop;
+       uint32_t powerState = kPowerStateZero;
+
+       if (fPowerClients && client) {
+               OSNumber * num = (OSNumber *) fPowerClients->getObject(client);
+               if (num) {
+                       powerState = num->unsigned32BitValue();
+               }
+       }
+       return powerState;
 }
 
 //*********************************************************************************
-// [public virtual] 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.
+// [protected] powerOverrideOnPriv
 //*********************************************************************************
 
-bool IOService::activityTickle ( unsigned long type, unsigned long stateNumber )
+IOReturn
+IOService::powerOverrideOnPriv( void )
 {
-       IOPMRequest *   request;
-       bool                    noPowerChange = true;
-
-    if ( initialized && stateNumber && (type == kIOPMSuperclassPolicy1) )
-       {
-        IOLockLock(fActivityLock);
-
-               // Record device activity for the idle timer handler.
-
-        fDeviceActive = true;
-        clock_get_uptime(&fDeviceActiveTimestamp);
-
-               // 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 < (long)stateNumber)
-               {
-                       fActivityTicklePowerState = stateNumber;
-                       noPowerChange = false;
+       IOPMRequest * request;
 
-                       request = acquirePMRequest( this, kIOPMRequestTypeActivityTickle );
-                       if (request)
-                       {
-                               request->fArg0 = (void *) stateNumber;  // power state
-                               request->fArg1 = (void *) true;                 // power rise
-                               submitPMRequest(request);
-                       }
-               }
+       if (!initialized) {
+               return IOPMNotYetInitialized;
+       }
 
-               IOLockUnlock(fActivityLock);
+       if (gIOPMWorkLoop->inGate()) {
+               fDeviceOverrideEnabled = true;
+               return IOPMNoErr;
        }
 
-       // Returns false if the activityTickle might cause a transition to a
-       // higher powered state, true otherwise.
+       request = acquirePMRequest( this, kIOPMRequestTypePowerOverrideOnPriv );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
 
-    return noPowerChange;
+       submitPMRequest( request );
+       return IOPMNoErr;
 }
 
 //*********************************************************************************
-// [public virtual] 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.
+// [protected] powerOverrideOffPriv
 //*********************************************************************************
 
-IOReturn IOService::setIdleTimerPeriod ( unsigned long period )
+IOReturn
+IOService::powerOverrideOffPriv( void )
 {
-       IOWorkLoop * wl = getPMworkloop();
+       IOPMRequest * request;
 
-    if (!initialized || !wl)
+       if (!initialized) {
                return IOPMNotYetInitialized;
+       }
 
-    OUR_PMLog(PMsetIdleTimerPeriod, period, 0);
-
-    fIdleTimerPeriod = period;
-
-    if ( period > 0 )
-    {
-               // make the timer event
-        if ( fIdleTimerEventSource == NULL )
-        {
-                       IOTimerEventSource * timerSrc;
-
-                       timerSrc = IOTimerEventSource::timerEventSource(
-                               this, PM_idle_timer_expired);
-                       
-            if (timerSrc && (wl->addEventSource(timerSrc) != kIOReturnSuccess))
-                       {
-                               timerSrc->release();
-                               timerSrc = 0;
-                       }
+       if (gIOPMWorkLoop->inGate()) {
+               fDeviceOverrideEnabled = false;
+               return IOPMNoErr;
+       }
 
-            fIdleTimerEventSource = timerSrc;
-        }
+       request = acquirePMRequest( this, kIOPMRequestTypePowerOverrideOffPriv );
+       if (!request) {
+               return kIOReturnNoMemory;
+       }
 
-        start_PM_idle_timer();
-    }
-    return IOPMNoErr;
+       submitPMRequest( request );
+       return IOPMNoErr;
 }
 
-//******************************************************************************
-// [public virtual] nextIdleTimeout
-//
-// Returns how many "seconds from now" the device should idle into its
-// next lowest power state.
-//******************************************************************************
+//*********************************************************************************
+// [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;
+       }
 
-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;
+       adjustPowerState();
 }
 
-//******************************************************************************
-// [public virtual] start_PM_idle_timer
-//
-// The parameter is a pointer to us.  Use it to call our timeout method.
-//******************************************************************************
+//*********************************************************************************
+// [private] computeDesiredState
+//*********************************************************************************
 
-void IOService::start_PM_idle_timer ( void )
+void
+IOService::computeDesiredState( unsigned long localClamp, bool computeOnly )
 {
-    static const int                    maxTimeout = 100000;
-    static const int                    minTimeout = 1;
-    AbsoluteTime                        uptime;
-    SInt32                              idle_in = 0;
+       OSIterator *        iter;
+       OSObject *          next;
+       IOPowerConnection * connection;
+       uint32_t            desiredState  = kPowerStateZero;
+       uint32_t            newPowerState = kPowerStateZero;
+       bool                hasChildren   = false;
 
-       if (!initialized || !fIdleTimerEventSource)
+       // Desired power state is always 0 without a controlling driver.
+
+       if (!fNumberOfPowerStates) {
+               fDesiredPowerState = kPowerStateZero;
                return;
+       }
 
-    IOLockLock(fActivityLock);
+       // 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);
+       }
 
-    clock_get_uptime(&uptime);
-    
-    // Subclasses may modify idle sleep algorithm
-    idle_in = nextIdleTimeout(uptime, fDeviceActiveTimestamp, fCurrentPowerState);
+       // 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;
+                       }
 
-    // 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;
-    }
+                       // Ignore child proxy when children are present.
+                       if (hasChildren && (client == gIOPMPowerClientChildProxy)) {
+                               continue;
+                       }
 
-    IOLockUnlock(fActivityLock);
+                       // Advisory tickles are irrelevant unless system is in full wake
+                       if (client == gIOPMPowerClientAdvisoryTickle &&
+                           !gIOPMAdvisoryTickleEnabled) {
+                               continue;
+                       }
 
-       fIdleTimerEventSource->setTimeout(idle_in, NSEC_PER_SEC);
-}
+                       desiredState = getPowerStateForClient(client);
+                       assert(desiredState < fNumberOfPowerStates);
+                       PM_LOG1("  %u %s\n",
+                           desiredState, client->getCStringNoCopy());
 
-//*********************************************************************************
-// [private] PM_idle_timer_expired
-//
-// The parameter is a pointer to us.  Use it to call our timeout method.
-//*********************************************************************************
+                       newPowerState = StateMax(newPowerState, desiredState);
 
-void PM_idle_timer_expired ( OSObject * ourSelves, IOTimerEventSource * )
-{
-    ((IOService *)ourSelves)->PM_idle_timer_expiration();
-}
+                       if (client == gIOPMPowerClientDevice) {
+                               fDeviceDesire = desiredState;
+                       }
+               }
+               iter->release();
+       }
 
-//*********************************************************************************
-// [public virtual] 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.
-//*********************************************************************************
+       // Factor in the temporary power desires.
 
-void IOService::PM_idle_timer_expiration ( void )
-{
-       IOPMRequest *   request;
-       bool                    restartTimer = true;
+       newPowerState = StateMax(newPowerState, localClamp);
+       newPowerState = StateMax(newPowerState, fTempClampPowerState);
 
-    if ( !initialized || !fIdleTimerPeriod )
-        return;
+       // Limit check against max power override.
 
-       IOLockLock(fActivityLock);
+       newPowerState = StateMin(newPowerState, fOverrideMaxPowerState);
 
-       // Check for device activity (tickles) over last timer period.
+       // Limit check against number of power states.
 
-       if (fDeviceActive)
-       {
-               // Device was active - do not drop power, restart timer.
-               fDeviceActive = false;
+       if (newPowerState >= fNumberOfPowerStates) {
+               newPowerState = fHighestPowerState;
        }
-       else
-       {
-               // No device activity - drop power state by one level.
-               // Decrement the cached tickle power state when possible.
-               // This value may be (-1) before activityTickle() is called,
-               // but the power drop request must be issued regardless.
 
-               if (fActivityTicklePowerState > 0)
-               {
-                       fActivityTicklePowerState--;
+#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)) */
 
-               request = acquirePMRequest( this, kIOPMRequestTypeActivityTickle );
-               if (request)
-               {
-                       request->fArg0 = (void *) 0;            // power state (irrelevant)
-                       request->fArg1 = (void *) false;        // power drop
-                       submitPMRequest( request );
+       fDesiredPowerState = newPowerState;
 
-                       // Do not restart timer until after the tickle request has been
-                       // processed.
+       PM_LOG1("  temp %u, clamp %u, current %u, new %u\n",
+           (uint32_t) localClamp, (uint32_t) fTempClampPowerState,
+           (uint32_t) fCurrentPowerState, newPowerState);
 
-                       restartTimer = false;
-               }
-    }
+       if (!computeOnly) {
+               // Restart idle timer if possible when device desire has increased.
+               // Or if an advisory desire exists.
 
-       IOLockUnlock(fActivityLock);
+               if (fIdleTimerPeriod && fIdleTimerStopped) {
+                       restartIdleTimer();
+               }
 
-       if (restartTimer)
-               start_PM_idle_timer();
+               // 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 virtual] command_received
+// [public] currentPowerConsumption
 //
 //*********************************************************************************
 
-void IOService::command_received ( void *statePtr , void *, void * , void * )
+unsigned long
+IOService::currentPowerConsumption( void )
 {
+       if (!initialized) {
+               return kIOPMUnknown;
+       }
+
+       return fCurrentPowerConsumption;
 }
 
 //*********************************************************************************
-// [public virtual] 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.
+// [deprecated] getPMworkloop
 //*********************************************************************************
 
-IOReturn IOService::setAggressiveness ( unsigned long type, unsigned long newLevel )
+#ifndef __LP64__
+IOWorkLoop *
+IOService::getPMworkloop( void )
 {
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-    IOService *                        child;
-
-    if (!initialized)
-               return IOPMNotYetInitialized;
-
-    if (getPMRootDomain() == this)
-        OUR_PMLog(kPMLogSetAggressiveness, type, newLevel);
-
-    if ( type <= kMaxType )
-    {
-        fAggressivenessValue[type] = newLevel;
-        fAggressivenessValid[type]  = true;
-    }
-
-    iter = getChildIterator(gIOPowerPlane);
-    if ( iter )
-    {
-        while ( (next = iter->getNextObject()) )
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection, next)) )
-            {
-                               if (connection->getReadyFlag() == false)
-                               {
-                                       PM_CONNECT("[%s] %s: connection not ready\n",
-                                               getName(), __FUNCTION__);
-                                       continue;
-                               }
-
-                child = ((IOService *)(connection->copyChildEntry(gIOPowerPlane)));
-                if ( child )
-                {
-                    child->setAggressiveness(type, newLevel);
-                    child->release();
-                }
-            }
-        }
-        iter->release();
-    }
-
-    return IOPMNoErr;
+       return gIOPMWorkLoop;
 }
+#endif
+
+#if NOT_YET
 
 //*********************************************************************************
-// [public virtual] getAggressiveness
-//
-// Called by the user client.
+// Power Parent/Children Applier
 //*********************************************************************************
 
-IOReturn IOService::getAggressiveness ( unsigned long type, unsigned long * currentLevel )
+static void
+applyToPowerChildren(
+       IOService *               service,
+       IOServiceApplierFunction  applier,
+       void *                    context,
+       IOOptionBits              options )
 {
-    if ( !initialized || (type > kMaxType) )
-        return kIOReturnBadArgument;
+       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();
+       }
+}
 
-    if ( !fAggressivenessValid[type] )
-        return kIOReturnInvalid;
-    *currentLevel = fAggressivenessValue[type];
+static void
+applyToPowerParent(
+       IOService *               service,
+       IOServiceApplierFunction  applier,
+       void *                    context,
+       IOOptionBits              options )
+{
+       PM_ASSERT_IN_GATE();
 
-    return kIOReturnSuccess;
+       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();
+       }
 }
 
-//*********************************************************************************
-// [public] getPowerState
-//
-//*********************************************************************************
+#endif /* NOT_YET */
 
-UInt32 IOService::getPowerState ( void )
-{
-    if (!initialized)
-        return 0;
+// MARK: -
+// MARK: Activity Tickle & Idle Timer
 
-    return fCurrentPowerState;
+void
+IOService::setAdvisoryTickleEnable( bool enable )
+{
+       gIOPMAdvisoryTickleEnabled = enable;
 }
 
 //*********************************************************************************
-// [public virtual] systemWake
+// [public] activityTickle
 //
-// Pass this to all power domain children. All those which are
-// power domains will pass it on to their children, etc.
+// 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.
 //*********************************************************************************
 
-IOReturn IOService::systemWake ( void )
+bool
+IOService::activityTickle( unsigned long type, unsigned long stateNumber )
 {
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-    IOService *                        theChild;
+       IOPMRequest *   request;
+       bool            noPowerChange = true;
+       uint32_t        tickleFlags;
 
-    OUR_PMLog(kPMLogSystemWake, 0, 0);
+       if (!initialized) {
+               return true; // no power change
+       }
+       if ((type == kIOPMSuperclassPolicy1) && StateOrder(stateNumber)) {
+               IOLockLock(fActivityLock);
 
-    iter = getChildIterator(gIOPowerPlane);
-    if ( iter )
-    {
-        while ( (next = iter->getNextObject()) )
-        {
-            if ( (connection = OSDynamicCast(IOPowerConnection, next)) )
-            {
-                               if (connection->getReadyFlag() == false)
-                               {
-                                       PM_CONNECT("[%s] %s: connection not ready\n",
-                                               getName(), __FUNCTION__);
-                                       continue;
-                               }
+               // Record device activity for the idle timer handler.
 
-                theChild = (IOService *)connection->copyChildEntry(gIOPowerPlane);
-                if ( theChild )
-                {
-                       theChild->systemWake();
-                    theChild->release();
-                }
-            }
-        }
-        iter->release();
-    }
+               fDeviceWasActive = true;
+               fActivityTickleCount++;
+               clock_get_uptime(&fDeviceActiveTimestamp);
 
-    if ( fControllingDriver != NULL )
-    {
-        if ( fControllingDriver->didYouWakeSystem() )
-        {
-            makeUsable();
-        }
-    }
+               PM_ACTION_0(actionActivityTickle);
 
-    return IOPMNoErr;
-}
+               // Record the last tickle power state.
+               // This helps to filter out redundant tickles as
+               // this function may be called from the data path.
 
-//*********************************************************************************
-// [public virtual] temperatureCriticalForZone
-//*********************************************************************************
+               if ((fActivityTicklePowerState == kInvalidTicklePowerState)
+                   || StateOrder(fActivityTicklePowerState) < StateOrder(stateNumber)) {
+                       fActivityTicklePowerState = stateNumber;
+                       noPowerChange = false;
 
-IOReturn IOService::temperatureCriticalForZone ( IOService * whichZone )
-{
-    IOService *        theParent;
-    IOService *        theNub;
-    
-    OUR_PMLog(kPMLogCriticalTemp, 0, 0);
+                       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);
+                       }
+               }
 
-    if ( inPlane(gIOPowerPlane) && !fWeAreRoot )
-    {
-        theNub = (IOService *)copyParentEntry(gIOPowerPlane);
-        if ( theNub )
-        {
-            theParent = (IOService *)theNub->copyParentEntry(gIOPowerPlane);
-            theNub->release();
-            if ( theParent )
-            {
-                theParent->temperatureCriticalForZone(whichZone);
-                theParent->release();
-            }
-        }
-    }
-    return IOPMNoErr;
-}
+               IOLockUnlock(fActivityLock);
+       } else if ((type == kIOPMActivityTickleTypeAdvisory) &&
+           ((stateNumber = fDeviceUsablePowerState) != kPowerStateZero)) {
+               IOLockLock(fActivityLock);
 
-//*********************************************************************************
-// [public] powerOverrideOnPriv
-//*********************************************************************************
+               fAdvisoryTickled = true;
 
-IOReturn IOService::powerOverrideOnPriv ( void )
-{
-       IOPMRequest * request;
+               if (fAdvisoryTicklePowerState != stateNumber) {
+                       fAdvisoryTicklePowerState = stateNumber;
+                       noPowerChange = false;
 
-    if (!initialized)
-               return IOPMNotYetInitialized;
+                       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);
+                       }
+               }
 
-       if (gIOPMWorkLoop->inGate())
-       {
-               fDeviceOverrides = true;
-               return IOPMNoErr;
+               IOLockUnlock(fActivityLock);
        }
 
-       request = acquirePMRequest( this, kIOPMRequestTypePowerOverrideOnPriv );
-       if (!request)
-               return kIOReturnNoMemory;
+       // Returns false if the activityTickle might cause a transition to a
+       // higher powered state, true otherwise.
 
-       submitPMRequest( request );
-    return IOPMNoErr;
+       return noPowerChange;
 }
 
 //*********************************************************************************
-// [public] powerOverrideOffPriv
+// [private] handleActivityTickle
 //*********************************************************************************
 
-IOReturn IOService::powerOverrideOffPriv ( void )
+void
+IOService::handleActivityTickle( IOPMRequest * request )
 {
-       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.
+//******************************************************************************
 
-    if (!initialized)
+IOReturn
+IOService::setIdleTimerPeriod( unsigned long period )
+{
+       if (!initialized) {
                return IOPMNotYetInitialized;
+       }
 
-       if (gIOPMWorkLoop->inGate())
-       {
-               fDeviceOverrides = false;
-               return IOPMNoErr;
+       OUR_PMLog(kPMLogSetIdleTimerPeriod, period, fIdleTimerPeriod);
+
+       IOPMRequest * request =
+           acquirePMRequest( this, kIOPMRequestTypeSetIdleTimerPeriod );
+       if (!request) {
+               return kIOReturnNoMemory;
        }
 
-       request = acquirePMRequest( this, kIOPMRequestTypePowerOverrideOffPriv );
-       if (!request)
+       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);
+                       }
 
-       submitPMRequest( request );
-    return IOPMNoErr;
-}
+                       deassertPMDriverCall(&callEntry);
 
-//*********************************************************************************
-// [private] handlePowerOverrideChanged
-//*********************************************************************************
 
-void IOService::handlePowerOverrideChanged ( IOPMRequest * request )
-{
-       PM_ASSERT_IN_GATE();
-       if (request->getType() == kIOPMRequestTypePowerOverrideOnPriv)
-       {
-               OUR_PMLog(kPMLogOverrideOn, 0, 0);
-               fDeviceOverrides = true;
-    }
-       else
-       {
-               OUR_PMLog(kPMLogOverrideOff, 0, 0);
-               fDeviceOverrides = false;
-       }
+                       if ((result == IOPMAckImplied) || (result < 0)) {
+                               uint64_t nsec;
 
-       if (fControllingDriver && inPlane(gIOPowerPlane) && fParentsKnowState)
-       {
-               computeDesiredState();
-               changeState();
+                               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] enqueuePowerChange
+// [private] notifyChild
+//
+// Notify a power domain child of an upcoming power change.
+// If the object acknowledges the current change, we return TRUE.
 //*********************************************************************************
 
-IOReturn IOService::enqueuePowerChange ( 
-    unsigned long              flags,  
-    unsigned long              whatStateOrdinal, 
-    unsigned long              domainState, 
-    IOPowerConnection *        whichParent, 
-    unsigned long              singleParentState )
+bool
+IOService::notifyChild( IOPowerConnection * theNub )
 {
-       changeNoteItem          changeNote;
-       IOPMPowerState *        powerStatePtr;
+       IOReturn                ret = IOPMAckImplied;
+       unsigned long           childPower;
+       IOService *             theChild;
+       IOPMRequest *           childRequest;
+       IOPMPowerChangeFlags    requestArg2;
+       int                     requestType;
 
        PM_ASSERT_IN_GATE();
-       assert( fMachineState == kIOPM_Finished );
-    assert( whatStateOrdinal < fNumberOfPowerStates );
-
-    if (whatStateOrdinal >= fNumberOfPowerStates)
-        return IOPMAckImplied;
+       theChild = (IOService *)(theNub->copyChildEntry(gIOPowerPlane));
+       if (!theChild) {
+               return true;
+       }
 
-       powerStatePtr = &fPowerStates[whatStateOrdinal];
+       // Unless the child handles the notification immediately and returns
+       // kIOPMAckImplied, we'll be awaiting their acknowledgement later.
+       fHeadNotePendingAcks++;
+       theNub->setAwaitingAck(true);
 
-    // Initialize the change note
-    changeNote.flags                 = flags;
-    changeNote.newStateNumber        = whatStateOrdinal;
-    changeNote.outputPowerCharacter  = powerStatePtr->outputPowerCharacter;
-    changeNote.inputPowerRequirement = powerStatePtr->inputPowerRequirement;
-    changeNote.capabilityFlags       = powerStatePtr->capabilityFlags;
-    changeNote.parent                = NULL;
+       requestArg2 = fHeadNoteChangeFlags;
+       if (StateOrder(fHeadNotePowerState) < StateOrder(fCurrentPowerState)) {
+               requestArg2 |= kIOPMDomainPowerDrop;
+       }
 
-    if (flags & IOPMParentInitiated )
-    {
-        changeNote.domainState       = domainState;
-        changeNote.parent            = whichParent;
-        changeNote.singleParentState = singleParentState;
-    }
+       requestType = fIsPreChange ?
+           kIOPMRequestTypePowerDomainWillChange :
+           kIOPMRequestTypePowerDomainDidChange;
 
-       if (flags & IOPMWeInitiated )
-       {
-               start_our_change(&changeNote);
-               return 0;
-       }
-       else
-       {
-               return start_parent_change(&changeNote);
+       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] notifyInterestedDrivers
+// [private] notifyControllingDriver
 //*********************************************************************************
 
-bool IOService::notifyInterestedDrivers ( void )
+bool
+IOService::notifyControllingDriver( void )
 {
-       IOPMinformee *          informee;
-       IOPMinformeeList *      list = fInterestedDrivers;
-       DriverCallParam *       param;
-       IOItemCount                     count;
+       DriverCallParam *   param;
 
        PM_ASSERT_IN_GATE();
-       assert( fDriverCallBusy == false );
-       assert( fDriverCallParamCount == 0 );
-       assert( fHeadNotePendingAcks == 0 );
+       assert( fDriverCallParamCount == 0  );
+       assert( fControllingDriver );
 
-       count = list->numberOfItems();
-       if (!count)
-               goto done;      // no interested drivers
+       if (fInitialSetPowerState) {
+               fInitialSetPowerState = false;
+               fHeadNoteChangeFlags |= kIOPMInitialPowerChange;
 
-       // 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.
+               // Driver specified flag to skip the inital setPowerState()
+               if (fHeadNotePowerArrayEntry->capabilityFlags & kIOPMInitialDeviceState) {
+                       return false;
+               }
+       }
 
        param = (DriverCallParam *) fDriverCallParamPtr;
-       if (count > fDriverCallParamSlots)
-       {
-               if (fDriverCallParamSlots)
-               {
-                       assert(fDriverCallParamPtr);
-                       IODelete(fDriverCallParamPtr, DriverCallParam, fDriverCallParamSlots);
-                       fDriverCallParamPtr = 0;
-                       fDriverCallParamSlots = 0;
+       if (!param) {
+               param = IONew(DriverCallParam, 1);
+               if (!param) {
+                       return false; // no memory
                }
-
-               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++)
-       {
-               informee->timer = -1;
-               param[i].Target = informee;
-               informee->retain();
-        informee = list->nextInList( informee );
+               fDriverCallParamSlots = 1;
        }
 
-       fDriverCallParamCount = count;
-       fHeadNotePendingAcks = count;
-
-       // Machine state will be blocked pending callout thread completion.
+       param->Target = fControllingDriver;
+       fDriverCallParamCount = 1;
+       fDriverTimer = -1;
 
-       PM_LOCK();
+       // Block state machine and wait for callout completion.
+       assert(!fDriverCallBusy);
        fDriverCallBusy = true;
-       PM_UNLOCK();
        thread_call_enter( fDriverCallEntry );
-       return true;
 
-done:
-       // no interested drivers or did not schedule callout thread due to error.
-       return false;
+       return true;
 }
 
 //*********************************************************************************
-// [private] notifyInterestedDriversDone
+// [private] notifyControllingDriverDone
 //*********************************************************************************
 
-void IOService::notifyInterestedDriversDone ( void )
+void
+IOService::notifyControllingDriverDone( void )
 {
-       IOPMinformee *          informee;
-       IOItemCount                     count;
-       DriverCallParam *       param;
-       IOReturn                        result;
+       DriverCallParam *   param;
+       IOReturn            result;
 
        PM_ASSERT_IN_GATE();
        param = (DriverCallParam *) fDriverCallParamPtr;
-       count = fDriverCallParamCount;
 
        assert( fDriverCallBusy == false );
        assert( fMachineState == kIOPM_DriverThreadCallDone );
 
-       if (param && count)
-       {
-               for (IOItemCount i = 0; i < count; i++, param++)
-               {
-                       informee = (IOPMinformee *) param->Target;
-                       result   = param->Result;
+       if (param && fDriverCallParamCount) {
+               assert(fDriverCallParamCount == 1);
 
-                       if ((result == IOPMAckImplied) || (result < 0))
-                       {
-                               // child return IOPMAckImplied
-                               informee->timer = 0;
-                               fHeadNotePendingAcks--;
-                       }
-                       else if (informee->timer)
-                       {
-                assert(informee->timer == -1);
+               // the return value from setPowerState()
+               result = param->Result;
 
-                // 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 == IOPMAckImplied) || (result < 0)) {
+                       fDriverTimer = 0;
+               } else if (fDriverTimer) {
+                       assert(fDriverTimer == -1);
 
-                if (result < kMinAckTimeoutTicks)
-                    result = kMinAckTimeoutTicks;
+                       // 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.
 
-                informee->timer = (result / (ACK_TIMER_PERIOD / ns_per_us)) + 1;
+                       if (result < kMinAckTimeoutTicks) {
+                               result = kMinAckTimeoutTicks;
                        }
-                       // 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();
+                       fDriverTimer = (result / (ACK_TIMER_PERIOD / ns_per_us)) + 1;
                }
+               // else, child has already acked and driver_timer reset to 0.
 
                fDriverCallParamCount = 0;
 
-               if ( fHeadNotePendingAcks )
-               {
+               if (fDriverTimer) {
                        OUR_PMLog(kPMLogStartAckTimer, 0, 0);
                        start_ack_timer();
+                       getPMRootDomain()->reset_watchdog_timer(this, result / USEC_PER_SEC + 1);
                }
        }
 
-       // Hop back to original machine state path (from notifyAll)
-       fMachineState = fNextMachineState;
-
-       notifyChildren();
+       MS_POP(); // pushed by OurChangeSetPowerState()
+       fIsPreChange  = false;
 }
 
 //*********************************************************************************
-// [private] notifyChildren
+// [private] all_done
+//
+// A power change is done.
 //*********************************************************************************
 
-void IOService::notifyChildren ( void )
-{
-    OSIterator *               iter;
-    OSObject *                 next;
-    IOPowerConnection *        connection;
-       OSArray *                       children = 0;
+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;
+                               }
+                       }
+               }
 
-       if (fStrictTreeOrder)
-               children = OSArray::withCapacity(8);
+               return;
+       }
 
-    // Sum child power consumption in notifyChild()
-    fPowerStates[fHeadNoteState].staticPower = 0;
-
-    iter = getChildIterator(gIOPowerPlane);
-    if ( iter )
-    {
-        while ((next = iter->getNextObject()))
-        {
-            if ((connection = OSDynamicCast(IOPowerConnection, next)))
-            {
-                               if (connection->getReadyFlag() == false)
-                               {
-                                       PM_CONNECT("[%s] %s: connection not ready\n",
-                                               getName(), __FUNCTION__);
-                                       continue;
-                               }
+       // our power change
+       if (fHeadNoteChangeFlags & kIOPMSelfInitiated) {
+               // power state changed
+               if ((fHeadNoteChangeFlags & kIOPMNotDone) == 0) {
+                       trackSystemSleepPreventers(
+                               fCurrentPowerState, fHeadNotePowerState, fHeadNoteChangeFlags);
 
-                               if (children)
-                                       children->setObject( connection );
-                               else
-                                       notifyChild( connection,
-                                               fDriverCallReason == kDriverCallInformPreChange );
+                       // 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;
                        }
-        }
-        iter->release();
-    }
 
-       if (children)
-       {
-               if (children->getCount() == 0)
-               {
-                       children->release();
-                       children = 0;
+                       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;
                }
-               else
-               {
-                       assert(fNotifyChildArray == 0);
-                       fNotifyChildArray = children;
-                       fNextMachineState = fMachineState;
-                       fMachineState     = kIOPM_NotifyChildrenDone;
-               }               
        }
-}
 
-//*********************************************************************************
-// [private] notifyChildrenDone
-//*********************************************************************************
+       // parent-initiated power change
+       if (fHeadNoteChangeFlags & kIOPMParentInitiated) {
+               if (fHeadNoteChangeFlags & kIOPMRootChangeDown) {
+                       ParentChangeRootChangeDown();
+               }
 
-void IOService::notifyChildrenDone ( void )
-{
-       PM_ASSERT_IN_GATE();
-       assert(fNotifyChildArray);
-       assert(fMachineState == kIOPM_NotifyChildrenDone);
+               // power state changed
+               if ((fHeadNoteChangeFlags & kIOPMNotDone) == 0) {
+                       trackSystemSleepPreventers(
+                               fCurrentPowerState, fHeadNotePowerState, fHeadNoteChangeFlags);
 
-       // Interested drivers have all acked (if any), ack timer stopped.
-       // Notify one child, wait for it's 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.
+                       // 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
 
-       if (fNotifyChildArray->getCount())
-       {
-               IOPowerConnection *     connection;
-               connection = (IOPowerConnection *) fNotifyChildArray->getObject(0);
-               fNotifyChildArray->removeObject(0);
-               notifyChild( connection, fDriverCallReason == kDriverCallInformPreChange );
+                       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);
+                       }
+               }
        }
-       else
-       {
-               fNotifyChildArray->release();
-               fNotifyChildArray = 0;
-               fMachineState = fNextMachineState;
+
+       // 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] notifyAll
+// [private] OurChangeStart
+//
+// Begin the processing of a power change initiated by us.
 //*********************************************************************************
 
-IOReturn IOService::notifyAll ( bool is_prechange )
+void
+IOService::OurChangeStart( void )
 {
-       // Save the next machine_state to be restored by notifyInterestedDriversDone()
-
        PM_ASSERT_IN_GATE();
-       fNextMachineState = fMachineState;
-       fMachineState     = kIOPM_DriverThreadCallDone;
-       fDriverCallReason = is_prechange ?
-                                               kDriverCallInformPreChange : kDriverCallInformPostChange;
+       OUR_PMLog( kPMLogStartDeviceChange, fHeadNotePowerState, fCurrentPowerState );
 
-       if (!notifyInterestedDrivers())
-               notifyInterestedDriversDone();
+       // 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.
 
-       return IOPMWillAckLater;
+       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, static] pmDriverCallout
+// [private] requestDomainPowerApplier
 //
-// Thread call context
+// Call requestPowerDomainState() on all power parents.
 //*********************************************************************************
 
-IOReturn IOService::actionDriverCalloutDone (
-       OSObject * target,
-       void * arg0, void * arg1,
-       void * arg2, void * arg3 )
-{
-       IOServicePM * pwrMgt = (IOServicePM *) arg0;
-
-       PM_LOCK();
-       fDriverCallBusy = false;
-       PM_UNLOCK();
-
-       if (gIOPMReplyQueue)
-               gIOPMReplyQueue->signalWorkAvailable();
-
-       return kIOReturnSuccess;
-}
+struct IOPMRequestDomainPowerContext {
+       IOService *     child;          // the requesting child
+       IOPMPowerFlags  requestPowerFlags;// power flags requested by child
+};
 
-void IOService::pmDriverCallout ( IOService * from )
+static void
+requestDomainPowerApplier(
+       IORegistryEntry *   entry,
+       void *              inContext )
 {
-       assert(from);
-       switch (from->fDriverCallReason)
-       {
-               case kDriverCallSetPowerState:
-                       from->driverSetPowerState();
-                       break;
+       IOPowerConnection *             connection;
+       IOService *                     parent;
+       IOPMRequestDomainPowerContext * context;
 
-               case kDriverCallInformPreChange:
-               case kDriverCallInformPostChange:
-                       from->driverInformPowerChange();
-                       break;
+       if ((connection = OSDynamicCast(IOPowerConnection, entry)) == NULL) {
+               return;
+       }
+       parent = (IOService *) connection->copyParentEntry(gIOPowerPlane);
+       if (!parent) {
+               return;
+       }
 
-               default:
-                       IOPanic("IOService::pmDriverCallout bad machine state");
+       assert(inContext);
+       context = (IOPMRequestDomainPowerContext *) inContext;
+
+       if (connection->parentKnowsState() && connection->getReadyFlag()) {
+               parent->requestPowerDomainState(
+                       context->requestPowerFlags,
+                       connection,
+                       IOPMLowestState);
        }
 
-       gIOPMWorkLoop->runAction(actionDriverCalloutDone,
-               /* target */ from,
-               /* arg0   */ (void *) from->pwrMgt );
+       parent->release();
 }
 
 //*********************************************************************************
-// [private] driverSetPowerState
+// [private] requestDomainPower
 //
-// Thread call context
+// 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.
 //*********************************************************************************
 
-void IOService::driverSetPowerState ( void )
+IOReturn
+IOService::requestDomainPower(
+       IOPMPowerStateIndex ourPowerState,
+       IOOptionBits        options )
 {
-       IOService *                     driver;
-       unsigned long           powerState;
-       DriverCallParam *       param;
-       IOReturn                        result;
-    AbsoluteTime        end;
+       IOPMPowerFlags                  requestPowerFlags;
+       IOPMPowerStateIndex             maxPowerState;
+       IOPMRequestDomainPowerContext   context;
 
-       assert( fDriverCallBusy );
-       param = (DriverCallParam *) fDriverCallParamPtr;
-       assert( param );
-       assert( fDriverCallParamCount == 1 );
+       PM_ASSERT_IN_GATE();
+       assert(ourPowerState < fNumberOfPowerStates);
+       if (ourPowerState >= fNumberOfPowerStates) {
+               return kIOReturnBadArgument;
+       }
+       if (IS_PM_ROOT) {
+               return kIOReturnSuccess;
+       }
 
-       driver = fControllingDriver;
-       powerState = fHeadNoteState;
+       // Fetch our input power flags for the requested power state.
+       // Parent request is stated in terms of required power flags.
 
-       if (!fWillPMStop)
-       {
-               OUR_PMLog(          kPMLogProgramHardware, (UInt32) this, powerState);
-        clock_get_uptime(&fDriverCallStartTime);
-               result = driver->setPowerState( powerState, this );
-        clock_get_uptime(&end);
-               OUR_PMLog((UInt32) -kPMLogProgramHardware, (UInt32) this, (UInt32) result);
-
-#if LOG_SETPOWER_TIMES
-        if ((result == IOPMAckImplied) || (result < 0))
-        {
-            uint64_t    nsec;
-
-            SUB_ABSOLUTETIME(&end, &fDriverCallStartTime);
-            absolutetime_to_nanoseconds(end, &nsec);
-            if (nsec > LOG_SETPOWER_TIMES)
-                PM_DEBUG("%s::setPowerState(%p, %lu -> %lu) took %d ms\n",
-                    fName, this, fCurrentPowerState, powerState, NS_TO_MS(nsec));
-        }
-#endif
+       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;
+               }
        }
-       else
-               result = kIOPMAckImplied;
 
-       param->Result = result;
+done:
+       return kIOReturnSuccess;
 }
 
 //*********************************************************************************
-// [private] driverInformPowerChange
-//
-// Thread call context
+// [private] OurSyncStart
 //*********************************************************************************
 
-void IOService::driverInformPowerChange ( void )
+void
+IOService::OurSyncStart( void )
 {
-       IOItemCount                     count;
-       IOPMinformee *          informee;
-       IOService *                     driver;
-       IOReturn                        result;
-       IOPMPowerFlags          powerFlags;
-       unsigned long           powerState;
-       DriverCallParam *       param;
-    AbsoluteTime        end;
-
-       assert( fDriverCallBusy );
-       param = (DriverCallParam *) fDriverCallParamPtr;
-       count = fDriverCallParamCount;
-       assert( count && param );
+       PM_ASSERT_IN_GATE();
 
-       powerFlags = fHeadNoteCapabilityFlags;
-       powerState = fHeadNoteState;
+       if (fInitialPowerChange) {
+               return;
+       }
 
-       for (IOItemCount i = 0; i < count; i++)
-       {
-               informee = (IOPMinformee *) param->Target;
-               driver   = informee->whatObject;
+       PM_ACTION_2(actionPowerChangeStart, fHeadNotePowerState, &fHeadNoteChangeFlags);
 
-               if (!fWillPMStop && informee->active)
-               {
-                       if (fDriverCallReason == kDriverCallInformPreChange)
-                       {
-                               OUR_PMLog(kPMLogInformDriverPreChange, (UInt32) this, powerState);
-                clock_get_uptime(&informee->startTime);
-                               result = driver->powerStateWillChangeTo(powerFlags, powerState, this);
-                clock_get_uptime(&end);
-                               OUR_PMLog((UInt32)-kPMLogInformDriverPreChange, (UInt32) this, result);
-                       }
-                       else
-                       {
-                               OUR_PMLog(kPMLogInformDriverPostChange, (UInt32) this, powerState);
-                clock_get_uptime(&informee->startTime);
-                               result = driver->powerStateDidChangeTo(powerFlags, powerState, this);
-                clock_get_uptime(&end);
-                               OUR_PMLog((UInt32)-kPMLogInformDriverPostChange, (UInt32) this, result);
-                       }
+       if (fHeadNoteChangeFlags & kIOPMNotDone) {
+               OurChangeFinish();
+               return;
+       }
 
-#if LOG_SETPOWER_TIMES
-            if ((result == IOPMAckImplied) || (result < 0))
-            {
-                uint64_t nsec;
-
-                SUB_ABSOLUTETIME(&end, &informee->startTime);
-                absolutetime_to_nanoseconds(end, &nsec);
-                if (nsec > LOG_SETPOWER_TIMES)
-                    PM_DEBUG("%s::powerState%sChangeTo(%p, %s, %lu -> %lu) took %d ms\n",
-                        driver->getName(),
-                        (fDriverCallReason == kDriverCallInformPreChange) ? "Will" : "Did",
-                        driver, fName, fCurrentPowerState, powerState, NS_TO_MS(nsec));
-            }
-#endif
-               }
-               else
-                       result = kIOPMAckImplied;
+       if (fHeadNoteChangeFlags & kIOPMSyncTellPowerDown) {
+               fDoNotPowerDown = false;
 
-               param->Result = result;
-               param++;
+               // 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] notifyChild
+// [private] OurChangeTellClientsPowerDown
 //
-// Notify a power domain child of an upcoming power change.
-// If the object acknowledges the current change, we return TRUE.
+// 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.
 //*********************************************************************************
 
-bool IOService::notifyChild ( IOPowerConnection * theNub, bool is_prechange )
+void
+IOService::OurChangeTellClientsPowerDown( void )
 {
-    IOReturn           k = IOPMAckImplied;
-    unsigned long      childPower;
-    IOService *                theChild;
-       IOPMRequest *   childRequest;
-       int                             requestType;
-
-       PM_ASSERT_IN_GATE();
-    theChild = (IOService *)(theNub->copyChildEntry(gIOPowerPlane));
-    if (!theChild)
-    {
-               assert(false);
-        return true;
-    }
-
-    // Unless the child handles the notification immediately and returns
-    // kIOPMAckImplied, we'll be awaiting their acknowledgement later.
-       fHeadNotePendingAcks++;
-    theNub->setAwaitingAck(true);
-    
-       requestType = is_prechange ?
-               kIOPMRequestTypePowerDomainWillChange :
-               kIOPMRequestTypePowerDomainDidChange;
-
-       childRequest = acquirePMRequest( theChild, requestType );
-       if (childRequest)
-       {
-        theNub->retain();
-               childRequest->fArg0 = (void *) fHeadNoteOutputFlags;
-               childRequest->fArg1 = (void *) theNub;
-               childRequest->fArg2 = (void *) (fHeadNoteState < fCurrentPowerState);
-               theChild->submitPMRequest( childRequest );
-               k = IOPMWillAckLater;
+       if (!IS_ROOT_DOMAIN) {
+               fMachineState = kIOPM_OurChangeTellPriorityClientsPowerDown;
+       } else {
+               fMachineState = kIOPM_OurChangeTellUserPMPolicyPowerDown;
        }
-       else
-       {
-               k = IOPMAckImplied;
-               fHeadNotePendingAcks--;  
-               theNub->setAwaitingAck(false);
-        childPower = theChild->currentPowerConsumption();
-        if ( childPower == kIOPMUnknown )
-        {
-            fPowerStates[fHeadNoteState].staticPower = kIOPMUnknown;
-        } else {
-            if ( fPowerStates[fHeadNoteState].staticPower != kIOPMUnknown )
-            {
-                fPowerStates[fHeadNoteState].staticPower += childPower;
-            }
-        }
-    }
+       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;
 
-    theChild->release();
-       return (k == IOPMAckImplied);
+       tellClientsWithResponse(kIOPMMessageLastCallBeforeSleep);
 }
 
 //*********************************************************************************
-// [private] OurChangeTellClientsPowerDown
+// [private] OurChangeTellPriorityClientsPowerDown
 //
-// 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.
+// All applications and kernel clients have acknowledged our intention to drop
+// power.  Here we notify "priority" clients that we are lowering power.
 //*********************************************************************************
 
-void IOService::OurChangeTellClientsPowerDown ( void )
+void
+IOService::OurChangeTellPriorityClientsPowerDown( void )
 {
-    fMachineState = kIOPM_OurChangeTellPriorityClientsPowerDown;
-    tellChangeDown1(fHeadNoteState);
+       fMachineState = kIOPM_OurChangeNotifyInterestedDriversWillChange;
+       tellChangeDown2(fHeadNotePowerState);
 }
 
 //*********************************************************************************
-// [private] OurChangeTellPriorityClientsPowerDown
+// [private] OurChangeTellCapabilityWillChange
 //
-// 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.
+// Extra stage for root domain to notify apps and drivers about the
+// system capability change when raising power state.
 //*********************************************************************************
 
-void IOService::OurChangeTellPriorityClientsPowerDown ( void )
+void
+IOService::OurChangeTellCapabilityWillChange( void )
 {
-    fMachineState = kIOPM_OurChangeNotifyInterestedDriversWillChange;
-    tellChangeDown2(fHeadNoteState);
+       if (!IS_ROOT_DOMAIN) {
+               return OurChangeNotifyInterestedDriversWillChange();
+       }
+
+       tellSystemCapabilityChange( kIOPM_OurChangeNotifyInterestedDriversWillChange );
 }
 
 //*********************************************************************************
 // [private] 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.
+// All applications and kernel clients have acknowledged our power state change.
+// Here we notify interested drivers pre-change.
 //*********************************************************************************
 
-void IOService::OurChangeNotifyInterestedDriversWillChange ( void )
-{
-    fMachineState = kIOPM_OurChangeSetPowerState;
-    notifyAll( true );
+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
 //
-// 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.
+// Instruct our controlling driver to program the hardware for the power state
+// change. Wait for async completions.
 //*********************************************************************************
 
-void IOService::OurChangeSetPowerState ( void )
+void
+IOService::OurChangeSetPowerState( void )
 {
-    fNextMachineState = kIOPM_OurChangeWaitForPowerSettle;
+       MS_PUSH( kIOPM_OurChangeWaitForPowerSettle );
        fMachineState     = kIOPM_DriverThreadCallDone;
        fDriverCallReason = kDriverCallSetPowerState;
 
-       if (notifyControllingDriver() == false)
+       if (notifyControllingDriver() == false) {
                notifyControllingDriverDone();
+       }
 }
 
 //*********************************************************************************
 // [private] OurChangeWaitForPowerSettle
 //
-// 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 controlling driver has completed the power state change we initiated.
+// Wait for the driver specified settle time to expire.
 //*********************************************************************************
 
-void IOService::OurChangeWaitForPowerSettle ( void )
+void
+IOService::OurChangeWaitForPowerSettle( void )
 {
        fMachineState = kIOPM_OurChangeNotifyInterestedDriversDidChange;
-    fSettleTimeUS = compute_settle_time();
-    if ( fSettleTimeUS )
-    {
-               startSettleTimer(fSettleTimeUS);
-       }
+       startSettleTimer();
 }
 
 //*********************************************************************************
 // [private] OurChangeNotifyInterestedDriversDidChange
 //
-// 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.
+// Power has settled on a power change we initiated. Here we notify
+// all our interested drivers post-change.
 //*********************************************************************************
 
-void IOService::OurChangeNotifyInterestedDriversDidChange ( void )
+void
+IOService::OurChangeNotifyInterestedDriversDidChange( void )
 {
-    fMachineState = kIOPM_OurChangeFinish;
-    notifyAll(false);
+       IOPMrootDomain * rootDomain;
+       if ((rootDomain = getPMRootDomain()) == this) {
+               rootDomain->tracePoint( IS_POWER_DROP ?
+                   kIOPMTracePointSleepDidChangeInterests :
+                   kIOPMTracePointWakeDidChangeInterests  );
+       }
+
+       notifyAll( kIOPM_OurChangeTellCapabilityDidChange );
 }
 
 //*********************************************************************************
-// [private] OurChangeFinish
+// [private] OurChangeTellCapabilityDidChange
 //
-// 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.
+// For root domain to notify capability power-change.
 //*********************************************************************************
 
-void IOService::OurChangeFinish ( void )
+void
+IOService::OurChangeTellCapabilityDidChange( void )
 {
-    all_done();
+       if (!IS_ROOT_DOMAIN) {
+               return OurChangeFinish();
+       }
+
+       getPMRootDomain()->tracePoint( IS_POWER_DROP ?
+           kIOPMTracePointSleepCapabilityClients :
+           kIOPMTracePointWakeCapabilityClients  );
+
+       tellSystemCapabilityChange( kIOPM_OurChangeFinish );
 }
 
 //*********************************************************************************
-// [private] ParentDownTellPriorityClientsPowerDown
+// [private] OurChangeFinish
 //
-// 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.
+// Done with this self-induced power state change.
 //*********************************************************************************
 
-void IOService::ParentDownTellPriorityClientsPowerDown ( void )
+void
+IOService::OurChangeFinish( void )
 {
-    fMachineState = kIOPM_ParentDownNotifyInterestedDriversWillChange;
-       tellChangeDown2(fHeadNoteState);
+       all_done();
 }
 
+// MARK: -
+// MARK: Power Change Initiated by Parent
+
 //*********************************************************************************
-// [private] ParentDownNotifyInterestedDriversWillChange
+// [private] ParentChangeStart
 //
-// 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.
+// Here we begin the processing of a power change initiated by our parent.
 //*********************************************************************************
 
-void IOService::ParentDownNotifyInterestedDriversWillChange ( void )
+IOReturn
+IOService::ParentChangeStart( void )
 {
-    fMachineState = kIOPM_ParentDownSetPowerState;
-       notifyAll( true );
+       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] ParentDownSetPowerState
+//******************************************************************************
+// [private] ParentChangeRootChangeDown
 //
-// 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.
-//*********************************************************************************
+// 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::ParentDownSetPowerState ( void )
+void
+IOService::ParentChangeRootChangeDown( void )
 {
-       fNextMachineState = kIOPM_ParentDownWaitForPowerSettle;
-       fMachineState     = kIOPM_DriverThreadCallDone;
-       fDriverCallReason = kDriverCallSetPowerState;
+       // Always stop the idle timer before root power down
+       if (fIdleTimerPeriod && !fIdleTimerStopped) {
+               fIdleTimerStopped = true;
+               if (fIdleTimer && thread_call_cancel(fIdleTimer)) {
+                       release();
+               }
+       }
 
-       if (notifyControllingDriver() == false)
-               notifyControllingDriverDone();
+       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] ParentDownWaitForPowerSettle
+// [private] ParentChangeTellPriorityClientsPowerDown
 //
-// 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.
+// All applications and kernel clients have acknowledged our intention to drop
+// power.  Here we notify "priority" clients that we are lowering power.
 //*********************************************************************************
 
-void IOService::ParentDownWaitForPowerSettle ( void )
+void
+IOService::ParentChangeTellPriorityClientsPowerDown( void )
 {
-       fMachineState = kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange;
-    fSettleTimeUS = compute_settle_time();
-    if ( fSettleTimeUS )
-    {
-       startSettleTimer(fSettleTimeUS);
-       }
+       fMachineState = kIOPM_ParentChangeNotifyInterestedDriversWillChange;
+       tellChangeDown2(fHeadNotePowerState);
 }
 
 //*********************************************************************************
-// [private] ParentDownNotifyDidChangeAndAcknowledgeChange
+// [private] ParentChangeTellCapabilityWillChange
 //
-// Power has settled on a power change initiated by our parent.  Here we
-// notify interested parties.
+// All (legacy) applications and kernel clients have acknowledged, extra stage for
+// root domain to notify apps and drivers about the system capability change.
 //*********************************************************************************
 
-void IOService::ParentDownNotifyDidChangeAndAcknowledgeChange ( void )
+void
+IOService::ParentChangeTellCapabilityWillChange( void )
 {
-    fMachineState = kIOPM_ParentDownAcknowledgeChange;
-       notifyAll(false);       
+       if (!IS_ROOT_DOMAIN) {
+               return ParentChangeNotifyInterestedDriversWillChange();
+       }
+
+       tellSystemCapabilityChange( kIOPM_ParentChangeNotifyInterestedDriversWillChange );
 }
 
 //*********************************************************************************
-// [private] ParentDownAcknowledgeChange
+// [private] ParentChangeNotifyInterestedDriversWillChange
 //
-// 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.
+// All applications and kernel clients have acknowledged our power state change.
+// Here we notify interested drivers pre-change.
 //*********************************************************************************
 
-void IOService::ParentDownAcknowledgeChange ( void )
+void
+IOService::ParentChangeNotifyInterestedDriversWillChange( void )
 {
-    IORegistryEntry *  nub;
-    IOService *                        parent;
-
-    nub = fHeadNoteParent;
-    nub->retain();
-    all_done();
-    parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-    if ( parent )
-    {
-        parent->acknowledgePowerChange((IOService *)nub);
-        parent->release();
-    }
-    nub->release();
+       notifyAll( kIOPM_ParentChangeSetPowerState );
 }
 
 //*********************************************************************************
-// [private] ParentUpSetPowerState
+// [private] ParentChangeSetPowerState
 //
-// 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.
+// Instruct our controlling driver to program the hardware for the power state
+// change. Wait for async completions.
 //*********************************************************************************
 
-void IOService::ParentUpSetPowerState ( void )
+void
+IOService::ParentChangeSetPowerState( void )
 {
-       fNextMachineState = kIOPM_ParentUpWaitForSettleTime;
+       MS_PUSH( kIOPM_ParentChangeWaitForPowerSettle );
        fMachineState     = kIOPM_DriverThreadCallDone;
        fDriverCallReason = kDriverCallSetPowerState;
 
-       if (notifyControllingDriver() == false)
+       if (notifyControllingDriver() == false) {
                notifyControllingDriverDone();
+       }
 }
 
 //*********************************************************************************
-// [private] ParentUpWaitForSettleTime
+// [private] ParentChangeWaitForPowerSettle
 //
-// 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.
+// Our controlling driver has completed the power state change initiated by our
+// parent. Wait for the driver specified settle time to expire.
 //*********************************************************************************
 
-void IOService::ParentUpWaitForSettleTime ( void )
+void
+IOService::ParentChangeWaitForPowerSettle( void )
 {
-       fMachineState = kIOPM_ParentUpNotifyInterestedDriversDidChange;
-    fSettleTimeUS = compute_settle_time();
-    if ( fSettleTimeUS )
-    {
-        startSettleTimer(fSettleTimeUS);
-    }
+       fMachineState = kIOPM_ParentChangeNotifyInterestedDriversDidChange;
+       startSettleTimer();
 }
 
 //*********************************************************************************
-// [private] ParentUpNotifyInterestedDriversDidChange
+// [private] ParentChangeNotifyInterestedDriversDidChange
 //
-// 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.
+// Power has settled on a power change initiated by our parent. Here we notify
+// all our interested drivers post-change.
 //*********************************************************************************
 
-void IOService::ParentUpNotifyInterestedDriversDidChange ( void )
+void
+IOService::ParentChangeNotifyInterestedDriversDidChange( void )
 {
-    fMachineState = kIOPM_ParentUpAcknowledgePowerChange;
-       notifyAll(false);       
+       notifyAll( kIOPM_ParentChangeTellCapabilityDidChange );
 }
 
 //*********************************************************************************
-// [private] ParentUpAcknowledgePowerChange
+// [private] ParentChangeTellCapabilityDidChange
 //
-// 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.
+// For root domain to notify capability power-change.
 //*********************************************************************************
 
-void IOService::ParentUpAcknowledgePowerChange ( void )
+void
+IOService::ParentChangeTellCapabilityDidChange( void )
 {
-    IORegistryEntry *  nub;
-    IOService *                        parent;
+       if (!IS_ROOT_DOMAIN) {
+               return ParentChangeAcknowledgePowerChange();
+       }
 
-    nub = fHeadNoteParent;
-    nub->retain();
-    all_done();
-    parent = (IOService *)nub->copyParentEntry(gIOPowerPlane);
-    if ( parent )
-    {
-        parent->acknowledgePowerChange((IOService *)nub);
-        parent->release();
-    }
-    nub->release();
+       tellSystemCapabilityChange( kIOPM_ParentChangeAcknowledgePowerChange );
 }
 
 //*********************************************************************************
-// [private] all_done
+// [private] ParentAcknowledgePowerChange
 //
-// 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.
+// Acknowledge our power parent that our power change is done.
 //*********************************************************************************
 
-void IOService::all_done ( void )
+void
+IOService::ParentChangeAcknowledgePowerChange( void )
 {
-    unsigned long      previous_state;
-
-    fMachineState = kIOPM_Finished;
-
-    // our power change
-    if ( fHeadNoteFlags & IOPMWeInitiated )
-    {
-        // could our driver switch to the new state?
-        if ( !( fHeadNoteFlags & IOPMNotDone) )
-        {
-                       // we changed, tell our parent
-                       if ( !fWeAreRoot )
-                       {
-                               ask_parent(fHeadNoteState);
-                       }
-
-            // yes, did power raise?
-            if ( fCurrentPowerState < fHeadNoteState )
-            {
-                // yes, inform clients and apps
-                tellChangeUp (fHeadNoteState);
-            }
-            previous_state = fCurrentPowerState;
-            // either way
-            fCurrentPowerState = fHeadNoteState;
-#if PM_VARS_SUPPORT
-                       fPMVars->myCurrentState = fCurrentPowerState;
-#endif
-            OUR_PMLog(kPMLogChangeDone, fCurrentPowerState, 0);
-
-            // inform subclass policy-maker
-            if (!fWillPMStop && fParentsKnowState)
-                powerChangeDone(previous_state);
-            else
-                PM_DEBUG("%s::powerChangeDone() skipped\n", getName());
-        }
-    }
-
-    // parent's power change
-    if ( fHeadNoteFlags & IOPMParentInitiated)
-    {
-        if (((fHeadNoteFlags & IOPMDomainWillChange) && (fCurrentPowerState >= fHeadNoteState)) ||
-                       ((fHeadNoteFlags & IOPMDomainDidChange) && (fCurrentPowerState < fHeadNoteState)))
-        {
-            // did power raise?
-            if ( fCurrentPowerState < fHeadNoteState )
-            {
-                // yes, inform clients and apps
-                tellChangeUp (fHeadNoteState);
-            }
-            // either way
-            previous_state = fCurrentPowerState;
-            fCurrentPowerState = fHeadNoteState;
-#if PM_VARS_SUPPORT
-                       fPMVars->myCurrentState = fCurrentPowerState;
-#endif
-            fMaxCapability = fControllingDriver->maxCapabilityForDomainState(fHeadNoteDomainState);
-
-            OUR_PMLog(kPMLogChangeDone, fCurrentPowerState, 0);
-
-            // inform subclass policy-maker
-            if (!fWillPMStop && fParentsKnowState)
-                powerChangeDone(previous_state);
-            else
-                PM_DEBUG("%s::powerChangeDone() skipped\n", getName());
-        }
-    }
-
-    if (fCurrentPowerState < fNumberOfPowerStates)
-    {
-        const IOPMPowerState * powerStatePtr = &fPowerStates[fCurrentPowerState];
-
-        fCurrentCapabilityFlags = powerStatePtr->capabilityFlags;
-        if (fCurrentCapabilityFlags & kIOPMStaticPowerValid)
-            fCurrentPowerConsumption = powerStatePtr->staticPower;
-    }
-
-    // When power rises enough to satisfy the tickle's desire for more power,
-    // the condition preventing idle-timer from dropping power is removed.
+       IORegistryEntry *   nub;
+       IOService *         parent;
 
-    if (fCurrentPowerState >= fIdleTimerMinPowerState)
-    {
-        fIdleTimerMinPowerState = 0;
-    }
+       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
+
 //*********************************************************************************
-// [public] settleTimerExpired
+// [private] settleTimerExpired
 //
 // Power has settled after our last change.  Notify interested parties that
 // there is a new power state.
 //*********************************************************************************
 
-void IOService::settleTimerExpired ( void )
+void
+IOService::settleTimerExpired( void )
 {
        fSettleTimeUS = 0;
+       gIOPMWorkQueue->signalWorkAvailable();
 }
 
 //*********************************************************************************
-// [private] compute_settle_time
+// settle_timer_expired
 //
-// Compute the power-settling delay in microseconds for the
-// change from myCurrentState to head_note_state.
+// Holds a retain while the settle timer callout is in flight.
 //*********************************************************************************
 
-unsigned long IOService::compute_settle_time ( void )
+static void
+settle_timer_expired( thread_call_param_t arg0, thread_call_param_t arg1 )
 {
-    unsigned long      totalTime;
-    unsigned long      i;
-
-       PM_ASSERT_IN_GATE();
-
-    // compute total time to attain the new state
-    totalTime = 0;
-    i = fCurrentPowerState;
-
-    // we're lowering power
-    if ( fHeadNoteState < fCurrentPowerState )
-    {
-        while ( i > fHeadNoteState )
-        {
-            totalTime +=  fPowerStates[i].settleDownTime;
-            i--;
-        }
-    }
-
-    // we're raising power
-    if ( fHeadNoteState > fCurrentPowerState )
-    {
-        while ( i < fHeadNoteState )
-        {
-            totalTime +=  fPowerStates[i+1].settleUpTime;
-            i++;
-        }
-    }
+       IOService * me = (IOService *) arg0;
 
-    return totalTime;
+       if (gIOPMWorkLoop && gIOPMWorkQueue) {
+               gIOPMWorkLoop->runAction(
+                       OSMemberFunctionCast(IOWorkLoop::Action, me, &IOService::settleTimerExpired),
+                       me);
+       }
+       me->release();
 }
 
 //*********************************************************************************
 // [private] startSettleTimer
 //
-// Enter a power-settling delay in microseconds and start a timer for that delay.
+// Calculate a power-settling delay in microseconds and start a timer.
 //*********************************************************************************
 
-IOReturn IOService::startSettleTimer ( unsigned long delay )
+void
+IOService::startSettleTimer( void )
 {
-    AbsoluteTime       deadline;
-       boolean_t               pending;
+#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.
 
-       retain();
-    clock_interval_to_deadline(delay, kMicrosecondScale, &deadline);
-    pending = thread_call_enter_delayed(fSettleTimer, deadline);
-       if (pending) release();
+       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--;
+               }
+       }
 
-    return IOPMNoErr;
+       // 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
 }
 
 //*********************************************************************************
-// [public] ackTimerTick
+// [private] ackTimerTick
 //
 // The acknowledgement timeout periodic timer has ticked.
 // If we are awaiting acks for a power change notification,
@@ -3810,540 +5236,419 @@ IOReturn IOService::startSettleTimer ( unsigned long delay )
 // machine state, false otherwise.
 //*********************************************************************************
 
-void IOService::ack_timer_ticked ( void )
+#ifndef __LP64__
+#if MACH_ASSERT
+__dead2
+#endif
+void
+IOService::ack_timer_ticked( void )
 {
        assert(false);
 }
+#endif /* !__LP64__ */
 
-bool IOService::ackTimerTick( void )
+bool
+IOService::ackTimerTick( void )
 {
-    IOPMinformee *             nextObject;
-       bool                            done = false;
+       IOPMinformee *      nextObject;
+       bool                done = false;
 
        PM_ASSERT_IN_GATE();
-    switch (fMachineState) {
-        case kIOPM_OurChangeWaitForPowerSettle:
-        case kIOPM_ParentDownWaitForPowerSettle:
-        case kIOPM_ParentUpWaitForSettleTime:
-            // 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, this, fCurrentPowerState, fHeadNoteState, NS_TO_MS(nsec));
-
-                    if (gIOKitDebug & kIOLogDebugPower)
-                    {
-                        panic("%s::setPowerState(%p, %lu -> %lu) timed out after %d ms",
-                            fName, this, fCurrentPowerState, fHeadNoteState, NS_TO_MS(nsec));
-                    }
-                    else
-                                       {
-                                               // Unblock state machine and pretend driver has acked.
-                                               done = true;
+       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 {
-                    // still waiting, set timer again
-                    start_ack_timer();
-                }
-            }
-            break;
-
-        case kIOPM_OurChangeSetPowerState:
-        case kIOPM_OurChangeFinish:
-        case kIOPM_ParentDownSetPowerState:
-        case kIOPM_ParentDownAcknowledgeChange:
-        case kIOPM_ParentUpSetPowerState:
-        case kIOPM_ParentUpAcknowledgePowerChange:
-               case kIOPM_NotifyChildrenDone:
-            // 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",
-                                nextObject->whatObject, fName, fCurrentPowerState, fHeadNoteState,
-                                NS_TO_MS(nsec));
-
-                            // Pretend driver has acked.
-                            fHeadNotePendingAcks--;
-                        }
-                    }
-                    nextObject = fInterestedDrivers->nextInList(nextObject);
-                }
-
-                // is that the last?
-                if ( fHeadNotePendingAcks == 0 )
-                {
-                    // yes, we can continue
+                               } 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;
-                } else {
-                    // no, set timer again
-                    start_ack_timer();
-                }
-            }
-            break;
-
-        case kIOPM_ParentDownTellPriorityClientsPowerDown:
-        case kIOPM_ParentDownNotifyInterestedDriversWillChange:
-        case kIOPM_OurChangeTellClientsPowerDown:
-        case kIOPM_OurChangeTellPriorityClientsPowerDown:
-        case kIOPM_OurChangeNotifyInterestedDriversWillChange:
-                       // apps didn't respond in time
-            cleanClientResponses(true);
-            OUR_PMLog(kPMLogClientTardy, 0, 1);
-                       // tardy equates to approval
-                       done = true;
-            break;
+                               }
+#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);
+                       }
 
-        default:
-            PM_TRACE("[%s] unexpected ack timer tick (state = %ld)\n",
-                               getName(), fMachineState);
-            break;
-    }
+                       // 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;
 }
 
 //*********************************************************************************
-// [private] start_ack_timer
+// [private] start_watchdog_timer
 //*********************************************************************************
-
-void IOService::start_ack_timer ( void )
+void
+IOService::start_watchdog_timer( void )
 {
-       start_ack_timer( ACK_TIMER_PERIOD, kNanosecondScale );
-}
+       int             timeout;
+       uint64_t        deadline;
 
-void IOService::start_ack_timer ( UInt32 interval, UInt32 scale )
-{
-    AbsoluteTime       deadline;
-       boolean_t               pending;
+       if (!fWatchdogTimer || (kIOSleepWakeWdogOff & gIOKitDebug)) {
+               return;
+       }
 
-    clock_interval_to_deadline(interval, scale, &deadline);
+       IOLockLock(fWatchdogLock);
 
-       retain();
-    pending = thread_call_enter_delayed(fAckTimer, deadline);
-       if (pending) release();
+       timeout = getPMRootDomain()->getWatchdogTimeout();
+       clock_interval_to_deadline(timeout, kSecondScale, &deadline);
+       fWatchdogDeadline = deadline;
+       start_watchdog_timer(deadline);
+       IOLockUnlock(fWatchdogLock);
 }
 
-//*********************************************************************************
-// [private] stop_ack_timer
-//*********************************************************************************
-
-void IOService::stop_ack_timer ( void )
+void
+IOService::start_watchdog_timer(uint64_t deadline)
 {
-       boolean_t               pending;
+       IOLockAssert(fWatchdogLock, kIOLockAssertOwned);
 
-    pending = thread_call_cancel(fAckTimer);
-       if (pending) release();
+       if (!thread_call_isactive(fWatchdogTimer)) {
+               thread_call_enter_delayed(fWatchdogTimer, deadline);
+       }
 }
 
 //*********************************************************************************
-// [static] settleTimerExpired
-//
-// Inside PM work loop's gate.
+// [private] stop_watchdog_timer
 //*********************************************************************************
 
-IOReturn
-IOService::actionAckTimerExpired (
-       OSObject * target,
-       void * arg0, void * arg1,
-       void * arg2, void * arg3 )
+void
+IOService::stop_watchdog_timer( void )
 {
-       IOService * me = (IOService *) target;
-       bool            done;
+       if (!fWatchdogTimer || (kIOSleepWakeWdogOff & gIOKitDebug)) {
+               return;
+       }
 
-       // done will be true if the timer tick unblocks the machine state,
-       // otherwise no need to signal the work loop.
+       IOLockLock(fWatchdogLock);
 
-       done = me->ackTimerTick();
-       if (done && gIOPMReplyQueue)
-               gIOPMReplyQueue->signalWorkAvailable();
+       thread_call_cancel(fWatchdogTimer);
+       fWatchdogDeadline = 0;
 
-       return kIOReturnSuccess;
+       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);
+               }
+       }
+
+       IOLockUnlock(fWatchdogLock);
 }
 
 //*********************************************************************************
-// ack_timer_expired
-//
-// Thread call function. Holds a retain while the callout is in flight.
+// reset_watchdog_timer
 //*********************************************************************************
 
 void
-IOService::ack_timer_expired ( thread_call_param_t arg0, thread_call_param_t arg1 )
+IOService::reset_watchdog_timer(IOService *blockedObject, int pendingResponseTimeout)
 {
-       IOService * me = (IOService *) arg0;
+       unsigned int i;
+       uint64_t    deadline;
+       IOService *obj;
 
-       if (gIOPMWorkLoop)
-       {
-               gIOPMWorkLoop->runAction(&actionAckTimerExpired, me);
+       if (!fWatchdogTimer || (kIOSleepWakeWdogOff & gIOKitDebug)) {
+               return;
        }
-       me->release();
+
+
+       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);
 }
 
+
 //*********************************************************************************
-// settleTimerExpired
+// [static] watchdog_timer_expired
 //
 // Inside PM work loop's gate.
 //*********************************************************************************
 
-static IOReturn
-settleTimerExpired (
-       OSObject * target,
-       void * arg0, void * arg1,
-       void * arg2, void * arg3 )
+void
+IOService::watchdog_timer_expired( thread_call_param_t arg0, thread_call_param_t arg1 )
 {
-       IOService * me = (IOService *) target;
-       me->settleTimerExpired();
-       return kIOReturnSuccess;
+       IOService * me = (IOService *) arg0;
+
+
+       gIOPMWatchDogThread = current_thread();
+       getPMRootDomain()->sleepWakeDebugTrig(true);
+       gIOPMWatchDogThread = NULL;
+       thread_call_free(me->fWatchdogTimer);
+       me->fWatchdogTimer = NULL;
+
+       return;
 }
 
-//*********************************************************************************
-// settle_timer_expired
-//
-// Thread call function. Holds a retain while the callout is in flight.
-//*********************************************************************************
 
-static void
-settle_timer_expired ( thread_call_param_t arg0, thread_call_param_t arg1 )
+IOWorkLoop *
+IOService::getIOPMWorkloop( void )
 {
-       IOService * me = (IOService *) arg0;
-
-       if (gIOPMWorkLoop && gIOPMReplyQueue)
-       {
-               gIOPMWorkLoop->runAction(settleTimerExpired, me);
-               gIOPMReplyQueue->signalWorkAvailable();
-       }
-       me->release();
+       return gIOPMWorkLoop;
 }
 
+
+
 //*********************************************************************************
-// [private] start_parent_change
-//
-// Here we begin the processing of a power change initiated by our parent.
+// [private] start_ack_timer
 //*********************************************************************************
 
-IOReturn IOService::start_parent_change ( const changeNoteItem * changeNote )
+void
+IOService::start_ack_timer( void )
 {
-    fHeadNoteFlags           = changeNote->flags;
-    fHeadNoteState           = changeNote->newStateNumber;
-    fHeadNoteOutputFlags     = changeNote->outputPowerCharacter;
-    fHeadNoteDomainState     = changeNote->domainState;
-    fHeadNoteParent          = changeNote->parent;
-    fHeadNoteCapabilityFlags = changeNote->capabilityFlags;
+       start_ack_timer( ACK_TIMER_PERIOD, kNanosecondScale );
+}
 
-       PM_ASSERT_IN_GATE();
-    OUR_PMLog( kPMLogStartParentChange, fHeadNoteState, fCurrentPowerState );
-
-    // Power domain is lowering power
-    if ( fHeadNoteState < fCurrentPowerState )
-    {
-               setParentInfo(
-                       changeNote->singleParentState,
-                       fHeadNoteParent, true );
-
-       // tell apps and kernel clients
-       fInitialChange = false;
-        fMachineState = kIOPM_ParentDownTellPriorityClientsPowerDown;
-               tellChangeDown1(fHeadNoteState);
-        return IOPMWillAckLater;
-    }
-
-    // Power domain is raising power
-    if ( fHeadNoteState > fCurrentPowerState )
-    {
-               IOPMPowerState * powerStatePtr;
-
-        if ( fDesiredPowerState > fCurrentPowerState )
-        {
-            if ( fDesiredPowerState < fHeadNoteState )
-            {
-                // We power up, but not all the way
-                fHeadNoteState = fDesiredPowerState;
-                               powerStatePtr = &fPowerStates[fHeadNoteState];
-                fHeadNoteOutputFlags = powerStatePtr->outputPowerCharacter;
-                fHeadNoteCapabilityFlags = powerStatePtr->capabilityFlags;
-                OUR_PMLog(kPMLogAmendParentChange, fHeadNoteState, 0);
-             }
-        } else {
-            // We don't need to change
-            fHeadNoteState = fCurrentPowerState;
-                       powerStatePtr = &fPowerStates[fHeadNoteState];
-            fHeadNoteOutputFlags = powerStatePtr->outputPowerCharacter;
-            fHeadNoteCapabilityFlags = powerStatePtr->capabilityFlags;
-            OUR_PMLog(kPMLogAmendParentChange, fHeadNoteState, 0);
-        }
-    }
-
-       if ((fHeadNoteState > fCurrentPowerState) &&
-               (fHeadNoteFlags & IOPMDomainDidChange))
-       {
-        // Parent did change up - start our change up
-        fInitialChange = false;
-        fMachineState = kIOPM_ParentUpSetPowerState;
-               notifyAll( true );
-        return IOPMWillAckLater;
-    }
+void
+IOService::start_ack_timer( UInt32 interval, UInt32 scale )
+{
+       AbsoluteTime    deadline;
+       boolean_t       pending;
 
-    all_done();
-    return IOPMAckImplied;
+       clock_interval_to_deadline(interval, scale, &deadline);
+
+       retain();
+       pending = thread_call_enter_delayed(fAckTimer, deadline);
+       if (pending) {
+               release();
+       }
 }
 
 //*********************************************************************************
-// [private] start_our_change
-//
-// Here we begin the processing of a power change initiated by us.
+// [private] stop_ack_timer
 //*********************************************************************************
 
-void IOService::start_our_change ( const changeNoteItem * changeNote )
+void
+IOService::stop_ack_timer( void )
 {
-    fHeadNoteFlags           = changeNote->flags;
-    fHeadNoteState           = changeNote->newStateNumber;
-    fHeadNoteOutputFlags     = changeNote->outputPowerCharacter;
-    fHeadNoteCapabilityFlags = changeNote->capabilityFlags;
+       boolean_t   pending;
 
-       PM_ASSERT_IN_GATE();
-
-    OUR_PMLog( kPMLogStartDeviceChange, fHeadNoteState, fCurrentPowerState );
-
-    // can our driver switch to the new state?
-    if (( fHeadNoteCapabilityFlags & IOPMNotAttainable ) ||
-               ((fMaxCapability < fHeadNoteState) && (!fWeAreRoot)))
-    {
-        // mark the change note un-actioned
-        fHeadNoteFlags |= IOPMNotDone;
-
-        // no, ask the parent to do it then
-        if ( !fWeAreRoot )
-        {
-            ask_parent(fHeadNoteState);
-        }
-        all_done();
-        return;
-    }
-
-    if ( !fInitialChange )
-    {
-        if ( fHeadNoteState == fCurrentPowerState )
-        {
-            // we initiated a null change; forget it
-            all_done();
-            return;
-        }
-    }
-    fInitialChange = false;
-
-    // dropping power?
-    if ( fHeadNoteState < fCurrentPowerState )
-    {
-        // yes, in case we have to wait for acks
-        fMachineState = kIOPM_OurChangeTellClientsPowerDown;
-        fDoNotPowerDown = false;
-
-        // ask apps and kernel clients if we can drop power
-        fOutOfBandParameter = kNotifyApps;
-               askChangeDown(fHeadNoteState);
-    } else {
-        // in case they don't all ack
-        fMachineState = kIOPM_OurChangeSetPowerState;
-        // notify interested drivers and children
-        notifyAll(true);
-    }
-}
-
-//*********************************************************************************
-// [private] 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;
-       const IOPMPowerState *  powerStatePtr;
-    unsigned long                      ourRequest;
-
-       PM_ASSERT_IN_GATE();
-    if (requestedState >= fNumberOfPowerStates)
-        return IOPMNoErr;
-
-       powerStatePtr = &fPowerStates[requestedState];
-       ourRequest    = powerStatePtr->inputPowerRequirement;
-
-    if ( powerStatePtr->capabilityFlags & (kIOPMChildClamp | kIOPMPreventIdleSleep) )
-    {
-        ourRequest |= kIOPMPreventIdleSleep;
-    }
-    if ( powerStatePtr->capabilityFlags & (kIOPMChildClamp2 | kIOPMPreventSystemSleep) )
-    {
-        ourRequest |= kIOPMPreventSystemSleep;
-    }
-
-    // is this a new desire?
-    if ( fPreviousRequest == ourRequest )
-    {  
-        // no, the parent knows already, just return
-        return IOPMNoErr;
-    }
-
-    if ( fWeAreRoot )
-    {
-        return IOPMNoErr;
-    }
-    fPreviousRequest = 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 )
-                    {
-                        OUR_PMLog(kPMLogRequestDenied, fPreviousRequest, 0);
-                    }
-                    parent->release();
-                }
-            }
-        }
-        iter->release();
-    }
-
-    return IOPMNoErr;
+       pending = thread_call_cancel(fAckTimer);
+       if (pending) {
+               release();
+       }
 }
 
 //*********************************************************************************
-// [private] notifyControllingDriver
+// [static] actionAckTimerExpired
+//
+// Inside PM work loop's gate.
 //*********************************************************************************
 
-bool IOService::notifyControllingDriver ( void )
+IOReturn
+IOService::actionAckTimerExpired(
+       OSObject * target,
+       void * arg0, void * arg1,
+       void * arg2, void * arg3 )
 {
-       DriverCallParam *       param;
-       unsigned long           powerState;
-
-       PM_ASSERT_IN_GATE();
-       assert( fDriverCallBusy == false );
-       assert( fDriverCallParamCount == 0  );
-       assert( fControllingDriver );
-
-       powerState = fHeadNoteState;
-    if (fPowerStates[powerState].capabilityFlags & IOPMNotAttainable )
-        return false;  // state not attainable
+       IOService * me = (IOService *) target;
+       bool        done;
 
-       param = (DriverCallParam *) fDriverCallParamPtr;
-       if (!param)
-       {
-               param = IONew(DriverCallParam, 1);
-               if (!param)
-                       return false;   // no memory
+       // done will be true if the timer tick unblocks the machine state,
+       // otherwise no need to signal the work loop.
 
-               fDriverCallParamPtr   = (void *) param;
-               fDriverCallParamSlots = 1;
+       done = me->ackTimerTick();
+       if (done && gIOPMWorkQueue) {
+               gIOPMWorkQueue->signalWorkAvailable();
        }
 
-       param->Target = fControllingDriver;
-       fDriverCallParamCount = 1;
-
-       fDriverTimer = -1;
-
-       // Machine state for this object will stall waiting for a reply
-       // from the callout thread.
-
-       PM_LOCK();
-       fDriverCallBusy = true;
-       PM_UNLOCK();
-       thread_call_enter( fDriverCallEntry );
-       return true;
+       return kIOReturnSuccess;
 }
 
 //*********************************************************************************
-// [private] notifyControllingDriverDone
+// ack_timer_expired
+//
+// Thread call function. Holds a retain while the callout is in flight.
 //*********************************************************************************
 
-void IOService::notifyControllingDriverDone( void )
+void
+IOService::ack_timer_expired( thread_call_param_t arg0, thread_call_param_t arg1 )
 {
-       DriverCallParam *       param;
-       IOReturn                        result;
-
-       PM_ASSERT_IN_GATE();
-       param = (DriverCallParam *) fDriverCallParamPtr;
-
-       assert( fDriverCallBusy == false );
-       assert( fMachineState == kIOPM_DriverThreadCallDone );
-
-       if (param)
-       {
-               assert(fDriverCallParamCount == 1);
-               
-               // the return value from setPowerState()
-               result = param->Result;
-
-               if ((result == IOPMAckImplied) || (result < 0))
-               {
-                       // child return IOPMAckImplied
-                       fDriverTimer = 0;
-               }
-               else if (fDriverTimer)
-               {
-                       assert(fDriverTimer == -1);
+       IOService * me = (IOService *) arg0;
 
-            // 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 (gIOPMWorkLoop) {
+               gIOPMWorkLoop->runAction(&actionAckTimerExpired, me);
+       }
+       me->release();
+}
 
-            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.
+// MARK: -
+// MARK: Client Messaging
 
-               fDriverCallParamCount = 0;
+//*********************************************************************************
+// [private] tellSystemCapabilityChange
+//*********************************************************************************
 
-               if ( fDriverTimer )
-               {
-                       OUR_PMLog(kPMLogStartAckTimer, 0, 0);
-                       start_ack_timer();
-               }
+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;
        }
 
-       // Hop back to original machine state path.
-       fMachineState = fNextMachineState;
+       tellClientsWithResponse( fOutOfBandMessage );
 }
 
 //*********************************************************************************
-// [public virtual] askChangeDown
+// [public] askChangeDown
 //
 // Ask registered applications and kernel clients if we can change to a lower
 // power state.
@@ -4354,13 +5659,14 @@ void IOService::notifyControllingDriverDone( void )
 // Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-bool IOService::askChangeDown ( unsigned long stateNum )
+bool
+IOService::askChangeDown( unsigned long stateNum )
 {
-    return tellClientsWithResponse( kIOMessageCanDevicePowerOff );
+       return tellClientsWithResponse( kIOMessageCanDevicePowerOff );
 }
 
 //*********************************************************************************
-// [public] tellChangeDown1
+// [private] tellChangeDown1
 //
 // Notify registered applications and kernel clients that we are definitely
 // dropping power.
@@ -4368,28 +5674,30 @@ bool IOService::askChangeDown ( unsigned long stateNum )
 // Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-bool IOService::tellChangeDown1 ( unsigned long stateNum )
+bool
+IOService::tellChangeDown1( unsigned long stateNum )
 {
-    fOutOfBandParameter = kNotifyApps;
-    return tellChangeDown(stateNum);
+       fOutOfBandParameter = kNotifyApps;
+       return tellChangeDown(stateNum);
 }
 
 //*********************************************************************************
-// [public] tellChangeDown2
+// [private] tellChangeDown2
 //
 // Notify priority clients that we are definitely dropping power.
 //
 // Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-bool IOService::tellChangeDown2 ( unsigned long stateNum )
+bool
+IOService::tellChangeDown2( unsigned long stateNum )
 {
-    fOutOfBandParameter = kNotifyPriority;
-    return tellChangeDown(stateNum);
+       fOutOfBandParameter = kNotifyPriority;
+       return tellChangeDown(stateNum);
 }
 
 //*********************************************************************************
-// [public virtual] tellChangeDown
+// [public] tellChangeDown
 //
 // Notify registered applications and kernel clients that we are definitely
 // dropping power.
@@ -4400,9 +5708,10 @@ bool IOService::tellChangeDown2 ( unsigned long stateNum )
 // Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-bool IOService::tellChangeDown ( unsigned long stateNum )
+bool
+IOService::tellChangeDown( unsigned long stateNum )
 {
-    return tellClientsWithResponse( kIOMessageDeviceWillPowerOff );
+       return tellClientsWithResponse( kIOMessageDeviceWillPowerOff );
 }
 
 //*********************************************************************************
@@ -4410,61 +5719,98 @@ bool IOService::tellChangeDown ( unsigned long stateNum )
 //
 //*********************************************************************************
 
-static void logAppTimeouts ( OSObject * object, void * context)
-{
-    struct context  *theContext = (struct context *)context;
-    OSObject        *flag;
-
-    if( !OSDynamicCast( IOService, object) ) {
-        flag = theContext->responseFlags->getObject(theContext->counter);
-        if (kOSBooleanTrue != flag)
-        {
-            OSString * clientID = 0;
-            theContext->us->messageClient(theContext->msgType, object, &clientID);
-            PM_ERROR(theContext->errorLog, clientID ? clientID->getCStringNoCopy() : "");
-            if (clientID)
-                clientID->release();
-        }
-        theContext->counter += 1;
-    }
-}
+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();
+                       }
 
-void IOService::cleanClientResponses ( bool logErrors )
-{
-    struct context theContext;
+                       PM_ERROR(context->errorLog, pid, name);
 
-    if (logErrors && fResponseArray) {
-        theContext.responseFlags    = fResponseArray;
-        theContext.serialNumber     = fSerialNumber;
-        theContext.counter          = 0;
-        theContext.msgType          = kIOMessageCopyClientID;
-        theContext.us               = this;
-        theContext.maxTimeRequested = 0;
-        theContext.stateNumber      = fHeadNoteState;
-        theContext.stateFlags       = fHeadNoteCapabilityFlags;
-        theContext.errorLog         = "PM notification timeout (%s)\n";
+                       // TODO: record message type if possible
+                       IOService::getPMRootDomain()->pmStatsRecordApplicationResponse(
+                               gIOPMStatsResponseTimedOut,
+                               name, 0, (30 * 1000), pid, object);
+               }
+       }
+}
 
-        switch ( fOutOfBandParameter ) {
-            case kNotifyApps:
-                applyToInterested(gIOAppPowerStateInterest, logAppTimeouts, (void *) &theContext);
-            case kNotifyPriority:
-            default:
-                break;
-        }
-    }
+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;
 
-    if (fResponseArray) 
-    {
-        // get rid of this stuff
-        fResponseArray->release();
-        fResponseArray = NULL;
-    }
+               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;
+               }
+       }
 
-    return;
+       if (IS_ROOT_DOMAIN) {
+               getPMRootDomain()->reset_watchdog_timer(this, 0);
+       }
+       if (fResponseArray) {
+               fResponseArray->release();
+               fResponseArray = NULL;
+       }
+       if (fNotifyClientArray) {
+               fNotifyClientArray->release();
+               fNotifyClientArray = NULL;
+       }
 }
 
 //*********************************************************************************
-// [public] tellClientsWithResponse
+// [protected] tellClientsWithResponse
 //
 // Notify registered applications and kernel clients that we are definitely
 // dropping power.
@@ -4472,51 +5818,149 @@ void IOService::cleanClientResponses ( bool logErrors )
 // Return true if we don't have to wait for acknowledgements
 //*********************************************************************************
 
-bool IOService::tellClientsWithResponse ( int messageType )
+bool
+IOService::tellClientsWithResponse( int messageType )
 {
-    struct context     theContext;
+       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;
+       }
 
-    fResponseArray = OSArray::withCapacity( 1 );
-    fSerialNumber += 1;
-    
-    theContext.responseFlags = fResponseArray;
-    theContext.serialNumber = fSerialNumber;
-    theContext.counter = 0;
-    theContext.msgType = messageType;
-    theContext.us = this;
-    theContext.maxTimeRequested = 0;
-    theContext.stateNumber = fHeadNoteState;
-    theContext.stateFlags = fHeadNoteCapabilityFlags;
-
-    switch ( fOutOfBandParameter ) {
-        case kNotifyApps:
-            applyToInterested(gIOAppPowerStateInterest,
-                               pmTellAppWithResponse, (void *)&theContext);
-            applyToInterested(gIOGeneralInterest,
-                               pmTellClientWithResponse, (void *)&theContext);
-            break;
-        case kNotifyPriority:
-            applyToInterested(gIOPriorityPowerStateInterest,
-                               pmTellClientWithResponse, (void *)&theContext);
-            break;
-    }
-    
-    // do we have to wait for somebody?
-    if ( !checkForDone() )
-    {
-        OUR_PMLog(kPMLogStartAckTimer,theContext.maxTimeRequested, 0);
-               start_ack_timer( theContext.maxTimeRequested / 1000, kMillisecondScale );       
-        return false;
-    }
-
-    // everybody responded
-    fResponseArray->release();
-    fResponseArray = NULL;
-    // cleanClientResponses(false);
-    
-    return true;
+       return true;
 }
 
 //*********************************************************************************
@@ -4526,118 +5970,464 @@ bool IOService::tellClientsWithResponse ( int messageType )
 // cookie we can identify the response with.
 //*********************************************************************************
 
-void IOService::pmTellAppWithResponse ( OSObject * object, void * context )
-{
-    struct context *   theContext = (struct context *) context;
-    IOServicePM *              pwrMgt = theContext->us->pwrMgt;
-    AbsoluteTime        now;
+void
+IOService::pmTellAppWithResponse( OSObject * object, void * arg )
+{
+       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++;
 
-    if( OSDynamicCast( IOService, object) )
-    {
-               // Automatically 'ack' in kernel clients
-        theContext->responseFlags->setObject(theContext->counter, kOSBooleanTrue);
+       // 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 );
+       }
 
-               const char *who = ((IOService *) object)->getName();
-               fPlatform->PMLog(who,
-                       kPMLogClientAcknowledge, theContext->msgType, * (UInt32 *) object);
-    } else {
-        UInt32 refcon = ((theContext->serialNumber & 0xFFFF)<<16)
-                         + (theContext->counter & 0xFFFF);
-               OUR_PMLog(kPMLogAppNotify, theContext->msgType, refcon);
+       msgType  = context->messageType;
+       msgIndex = context->responseArray->getCount();
+       msgRef   = ((context->serialNumber & 0xFFFF) << 16) + (msgIndex & 0xFFFF);
 
-#if LOG_APP_RESPONSE_TIMES
-        OSNumber * num;
-        clock_get_uptime(&now);
-        num = OSNumber::withNumber(AbsoluteTime_to_scalar(&now), sizeof(uint64_t) * 8);
-        if (num)
-        {
-            theContext->responseFlags->setObject(theContext->counter, num);
-            num->release();
-        }
-        else
-#endif
-        theContext->responseFlags->setObject(theContext->counter, kOSBooleanFalse);
+       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");
+               }
+       }
 
-        theContext->us->messageClient(theContext->msgType, object, (void *)refcon);
-        if ( theContext->maxTimeRequested < k30seconds )
-        {
-            theContext->maxTimeRequested = k30seconds;
-        }
+       if (context->notifyClients) {
+               context->notifyClients->setObject(msgIndex, object);
+       }
 
-        theContext->counter += 1;
-    }
+       context->us->messageClient(msgType, object, (void *)(uintptr_t) msgRef);
 }
 
 //*********************************************************************************
 // [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.
-// 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.
+// 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.
+//*********************************************************************************
+
+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);
+       }
+}
+
+//*********************************************************************************
+// [static private] pmTellCapabilityAppWithResponse
+//*********************************************************************************
+
+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));
+}
+
+//*********************************************************************************
+// [static private] pmTellCapabilityClientWithResponse
 //*********************************************************************************
 
-void IOService::pmTellClientWithResponse ( OSObject * object, void * context )
-{
-    struct context                          *theContext = (struct context *)context;
-    IOPowerStateChangeNotification          notify;
-    UInt32                                  refcon;
-    IOReturn                                retCode;
-    OSObject                                *theFlag;
+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);
+                       }
+               }
 
-    refcon = ((theContext->serialNumber & 0xFFFF)<<16) + (theContext->counter & 0xFFFF);
-    theContext->responseFlags->setObject(theContext->counter, kOSBooleanFalse);
+               if (context->enableTracing) {
+                       SUB_ABSOLUTETIME(&end, &start);
+                       absolutetime_to_nanoseconds(end, &nsec);
 
-    IOServicePM * pwrMgt = theContext->us->pwrMgt;
-    if (gIOKitDebug & kIOLogPower) {
-               OUR_PMLog(kPMLogClientNotify, refcon, (UInt32) theContext->msgType);
-               if (OSDynamicCast(IOService, object)) {
-                       const char *who = ((IOService *) object)->getName();
-                       fPlatform->PMLog(who,
-                               kPMLogClientNotify, * (UInt32 *) object, (UInt32) object);
-               } else if (OSDynamicCast(_IOServiceInterestNotifier, object)) {
-                       _IOServiceInterestNotifier *n = (_IOServiceInterestNotifier *) object;
-                       OUR_PMLog(kPMLogClientNotify, (UInt32) n->handler, 0);
-               }
-    }
-
-    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
-            theContext->responseFlags->replaceObject(theContext->counter, kOSBooleanTrue);
-                       OUR_PMLog(kPMLogClientAcknowledge, refcon, (UInt32) object);
-        } else {
-            // it does want time, and it hasn't responded yet
-            theFlag = theContext->responseFlags->getObject(theContext->counter);
-            if ( kOSBooleanTrue != theFlag ) 
-            {
-                // so note its time requirement
-                if ( theContext->maxTimeRequested < notify.returnValue ) 
-                {
-                    theContext->maxTimeRequested = notify.returnValue;
-                }
-            }
-        }
-    } else {
-               OUR_PMLog(kPMLogClientAcknowledge, refcon, 0);
-        // not a client of ours
-        // so we won't be waiting for response
-        theContext->responseFlags->replaceObject(theContext->counter, kOSBooleanTrue);
-    }
-    theContext->counter += 1;
-}
-
-//*********************************************************************************
-// [public virtual] tellNoChangeDown
+                       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);
+       }
+}
+
+//*********************************************************************************
+// [public] tellNoChangeDown
 //
 // Notify registered applications and kernel clients that we are not
 // dropping power.
@@ -4646,13 +6436,14 @@ void IOService::pmTellClientWithResponse ( OSObject * object, void * context )
 // the aborted destination state number.
 //*********************************************************************************
 
-void IOService::tellNoChangeDown ( unsigned long )
+void
+IOService::tellNoChangeDown( unsigned long )
 {
-    return tellClients( kIOMessageDeviceWillNotPowerOff );
+       return tellClients( kIOMessageDeviceWillNotPowerOff );
 }
 
 //*********************************************************************************
-// [public virtual] tellChangeUp
+// [public] tellChangeUp
 //
 // Notify registered applications and kernel clients that we are raising power.
 //
@@ -4660,481 +6451,853 @@ void IOService::tellNoChangeDown ( unsigned long )
 // the aborted destination state number.
 //*********************************************************************************
 
-void IOService::tellChangeUp ( unsigned long )
+void
+IOService::tellChangeUp( unsigned long )
 {
-    return tellClients( kIOMessageDeviceHasPoweredOn );
+       return tellClients( kIOMessageDeviceHasPoweredOn );
 }
 
 //*********************************************************************************
-// [public] tellClients
+// [protected] tellClients
 //
 // Notify registered applications and kernel clients of something.
 //*********************************************************************************
 
-void IOService::tellClients ( int messageType )
+void
+IOService::tellClients( int messageType )
 {
-    struct context theContext;
+       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 );
 
-    theContext.msgType = messageType;
-    theContext.us = this;
-    theContext.stateNumber = fHeadNoteState;
-    theContext.stateFlags = fHeadNoteCapabilityFlags;
+       context.notifyType    = kNotifyApps;
+       applyToInterested( gIOAppPowerStateInterest,
+           tellAppClientApplier, (void *) &context );
 
-    applyToInterested(gIOPriorityPowerStateInterest,tellClient,(void *)&theContext);
-    applyToInterested(gIOAppPowerStateInterest,tellClient, (void *)&theContext);
-    applyToInterested(gIOGeneralInterest,tellClient, (void *)&theContext);
+       applyToInterested( gIOGeneralInterest,
+           tellKernelClientApplier, (void *) &context );
 }
 
 //*********************************************************************************
-// [global] tellClient
+// [private] tellKernelClientApplier
 //
-// Notify a registered application or kernel client of something.
+// Message a kernel client.
 //*********************************************************************************
 
-void tellClient ( OSObject * object, void * context )
+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)
 {
-    struct context *                           theContext = (struct context *) context;
-    IOPowerStateChangeNotification     notify;
+       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++;
 
-    notify.powerRef    = (void *) 0;
-    notify.returnValue = 0;
-    notify.stateNumber = theContext->stateNumber;
-    notify.stateFlags  = theContext->stateFlags;
+       if (kIOLogDebugPower & gIOKitDebug) {
+               logClientIDForNotification(object, context, "MESG App");
+       }
 
-    theContext->us->messageClient(theContext->msgType, object, &notify);
+       context->us->messageClient(context->messageType, object, NULL);
 }
 
 //*********************************************************************************
 // [private] checkForDone
 //*********************************************************************************
 
-bool IOService::checkForDone ( void )
+bool
+IOService::checkForDone( void )
 {
-    int                        i = 0;
-    OSObject * theFlag;
+       int         i = 0;
+       OSObject *  theFlag;
+
+       if (fResponseArray == NULL) {
+               return true;
+       }
+
+       for (i = 0;; i++) {
+               theFlag = fResponseArray->getObject(i);
+
+               if (NULL == theFlag) {
+                       break;
+               }
 
-    if ( fResponseArray == NULL )
-    {
-        return true;
-    }
-    
-    for ( i = 0; ; i++ )
-    {
-        theFlag = fResponseArray->getObject(i);
-        if ( theFlag == NULL )
-        {
-            break;
-        }
-        if ( kOSBooleanTrue != theFlag ) 
-        {
-            return false;
-        }
-    }
-    return true;
+               if (kOSBooleanTrue != theFlag) {
+                       return false;
+               }
+       }
+       return true;
 }
 
 //*********************************************************************************
 // [public] responseValid
 //*********************************************************************************
 
-bool IOService::responseValid ( unsigned long x, int pid )
-{
-    UInt16                     serialComponent;
-    UInt16                     ordinalComponent;
-    OSObject *         theFlag;
-    unsigned long      refcon = (unsigned long) x;
-
-    serialComponent  = (refcon >> 16) & 0xFFFF;
-    ordinalComponent = (refcon & 0xFFFF);
-
-    if ( serialComponent != fSerialNumber )
-    {
-        return false;
-    }
-    
-    if ( fResponseArray == NULL )
-    {
-        return false;
-    }
-    
-    theFlag = fResponseArray->getObject(ordinalComponent);
-    
-    if ( theFlag == 0 )
-    {
-        return false;
-    }
-
-    OSNumber * num;
-    if ((num = OSDynamicCast(OSNumber, theFlag)))
-    {
-#if LOG_APP_RESPONSE_TIMES
-        AbsoluteTime   now;
-        AbsoluteTime   start;
-        uint64_t       nsec;
-
-        clock_get_uptime(&now);
-        AbsoluteTime_to_scalar(&start) = num->unsigned64BitValue();
-        SUB_ABSOLUTETIME(&now, &start);
-        absolutetime_to_nanoseconds(now, &nsec);
-
-        // > 100 ms
-        if (nsec > LOG_APP_RESPONSE_TIMES)
-        {
-            OSString * name = IOCopyLogNameForPID(pid);
-            PM_DEBUG("PM response took %d ms (%s)\n", NS_TO_MS(nsec),
-                name ? name->getCStringNoCopy() : "");
-            if (name)
-            name->release();
-        }
-#endif
-        theFlag = kOSBooleanFalse;
-    }
+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);
+       }
 
-    if ( kOSBooleanFalse == theFlag ) 
-    {
-        fResponseArray->replaceObject(ordinalComponent, kOSBooleanTrue);
-    }
-    
-    return true;
+       return true;
 }
 
 //*********************************************************************************
-// [public virtual] allowPowerChange
+// [public] 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 )
+IOReturn
+IOService::allowPowerChange( unsigned long refcon )
 {
        IOPMRequest * request;
 
-    if ( !initialized )
-    {
-        // we're unloading
-        return kIOReturnSuccess;
-    }
+       if (!initialized) {
+               // we're unloading
+               return kIOReturnSuccess;
+       }
 
        request = acquirePMRequest( this, kIOPMRequestTypeAllowPowerChange );
-       if (!request)
-       {
-        PM_ERROR("%s::%s no memory\n", getName(), __FUNCTION__);
+       if (!request) {
                return kIOReturnNoMemory;
        }
 
-       request->fArg0 = (void *) refcon;
-       request->fArg1 = (void *) proc_selfpid();
+       request->fArg0 = (void *)            refcon;
+       request->fArg1 = (void *)(uintptr_t) proc_selfpid();
+       request->fArg2 = (void *)            NULL;
        submitPMRequest( request );
 
        return kIOReturnSuccess;
 }
 
-IOReturn serializedAllowPowerChange ( OSObject *owner, void * refcon, void *, void *, void *)
-{
-       // [deprecated] public
-       return kIOReturnUnsupported;
-}
-
-IOReturn IOService::serializedAllowPowerChange2 ( unsigned long refcon )
+#ifndef __LP64__
+IOReturn
+IOService::serializedAllowPowerChange2( unsigned long refcon )
 {
        // [deprecated] public
        return kIOReturnUnsupported;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// [public virtual] cancelPowerChange
+// [public] 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 )
+IOReturn
+IOService::cancelPowerChange( unsigned long refcon )
 {
-       IOPMRequest * request;
+       IOPMRequest *   request;
+       char            name[128];
+       pid_t           pid = proc_selfpid();
 
-    if ( !initialized )
-    {
-        // we're unloading
-        return kIOReturnSuccess;
-    }
+       if (!initialized) {
+               // we're unloading
+               return kIOReturnSuccess;
+       }
 
-    OSString * name = IOCopyLogNameForPID(proc_selfpid());
-    PM_ERROR("PM notification cancel (%s)\n", name ? name->getCStringNoCopy() : "");
-    if (name)
-        name->release();
+       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)
-       {
-        PM_ERROR("%s::%s no memory\n", getName(), __FUNCTION__);
+       if (!request) {
                return kIOReturnNoMemory;
        }
 
-       request->fArg0 = (void *) refcon;
-       request->fArg1 = (void *) proc_selfpid();
+       request->fArg0 = (void *)            refcon;
+       request->fArg1 = (void *)(uintptr_t) proc_selfpid();
+       request->fArg2 = (void *)            OSString::withCString(name);
        submitPMRequest( request );
 
        return kIOReturnSuccess;
 }
 
-IOReturn serializedCancelPowerChange ( OSObject *owner, void * refcon, void *, void *, void *)
+//*********************************************************************************
+// cancelIdlePowerDown
+//
+// Internal method to trigger an idle cancel or revert
+//*********************************************************************************
+
+void
+IOService::cancelIdlePowerDown( IOService * service )
 {
-       // [deprecated] public
-       return kIOReturnUnsupported;
+       IOPMRequest * request;
+
+       request = acquirePMRequest(service, kIOPMRequestTypeIdleCancel);
+       if (request) {
+               submitPMRequest(request);
+       }
 }
 
-IOReturn IOService::serializedCancelPowerChange2 ( unsigned long refcon )
+#ifndef __LP64__
+IOReturn
+IOService::serializedCancelPowerChange2( unsigned long refcon )
 {
        // [deprecated] public
        return kIOReturnUnsupported;
 }
 
-#if 0
 //*********************************************************************************
-// c_PM_clamp_Timer_Expired (C Func)
+// PM_Clamp_Timer_Expired
 //
-// Called when our clamp timer expires...we will call the object method.
+// called when clamp timer expires...set power state to 0.
 //*********************************************************************************
 
-static void c_PM_Clamp_Timer_Expired ( OSObject * client, IOTimerEventSource * )
+void
+IOService::PM_Clamp_Timer_Expired( void )
 {
-    if (client)
-        ((IOService *)client)->PM_Clamp_Timer_Expired ();
 }
-#endif
 
 //*********************************************************************************
-// PM_Clamp_Timer_Expired
+// clampPowerOn
 //
-// called when clamp timer expires...set power state to 0.
+// Set to highest available power state for a minimum of duration milliseconds
 //*********************************************************************************
 
-void IOService::PM_Clamp_Timer_Expired ( void )
+void
+IOService::clampPowerOn( unsigned long duration )
 {
-#if 0
-    if ( ! initialized )
-    {
-        // we're unloading
-        return;
-    }
+}
+#endif /* !__LP64__ */
 
-  changePowerStateToPriv (0);
-#endif
+//*********************************************************************************
+//  configurePowerStateReport
+//
+//  Configures the IOStateReport for kPMPowerStateChannel
+//*********************************************************************************
+IOReturn
+IOService::configurePowerStatesReport( IOReportConfigureAction action, void *result )
+{
+       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;
 }
 
 //*********************************************************************************
-// clampPowerOn
+//  updatePowerStateReport
 //
-// Set to highest available power state for a minimum of duration milliseconds
+//  Updates the IOStateReport for kPMPowerStateChannel
+//*********************************************************************************
+IOReturn
+IOService::updatePowerStatesReport( IOReportConfigureAction action, void *result, void *destination )
+{
+       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;
+}
+
+//*********************************************************************************
+//  configureSimplePowerReport
+//
+//  Configures the IOSimpleReport for given channel id
 //*********************************************************************************
+IOReturn
+IOService::configureSimplePowerReport(IOReportConfigureAction action, void *result )
+{
+       IOReturn rc = kIOReturnSuccess;
+
+       if (!pwrMgt) {
+               return kIOReturnUnsupported;
+       }
+
+       if (!fNumberOfPowerStates) {
+               return rc;
+       }
+
+       switch (action) {
+       case kIOReportEnable:
+       case kIOReportDisable:
+               break;
 
-#define kFiveMinutesInNanoSeconds (300 * NSEC_PER_SEC)
+       case kIOReportGetDimensions:
+               SIMPLEREPORT_UPDATERES(kIOReportGetDimensions, result);
+               break;
+       }
+
+
+       return rc;
+}
 
-void IOService::clampPowerOn ( unsigned long duration )
+//*********************************************************************************
+//  updateSimplePowerReport
+//
+//  Updates the IOSimpleReport for the given chanel id
+//*********************************************************************************
+IOReturn
+IOService::updateSimplePowerReport( IOReportConfigureAction action, void *result, void *destination )
 {
-#if 0
-  changePowerStateToPriv (fNumberOfPowerStates-1);
+       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 (  pwrMgt->clampTimerEventSrc == NULL ) {
-    pwrMgt->clampTimerEventSrc = IOTimerEventSource::timerEventSource(this,
-                                                    c_PM_Clamp_Timer_Expired);
+       if (!fNumberOfPowerStates) {
+               return rc;
+       }
+       PM_LOCK();
 
-    IOWorkLoop * workLoop = getPMworkloop ();
+       switch (action) {
+       case kIOReportCopyChannelData:
 
-    if ( !pwrMgt->clampTimerEventSrc || !workLoop ||
-       ( workLoop->addEventSource(  pwrMgt->clampTimerEventSrc) != kIOReturnSuccess) ) {
+               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;
+               }
 
-   pwrMgt->clampTimerEventSrc->setTimeout(300*USEC_PER_SEC, USEC_PER_SEC);
-#endif
+
+               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
+
 //*********************************************************************************
-// [public virtual] setPowerState
+// [public] setPowerState
 //
 // Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::setPowerState (
+IOReturn
+IOService::setPowerState(
        unsigned long powerStateOrdinal, IOService * whatDevice )
 {
-    return IOPMNoErr;
+       return IOPMNoErr;
 }
 
 //*********************************************************************************
-// [public virtual] maxCapabilityForDomainState
+// [public] maxCapabilityForDomainState
 //
-// 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.
+// 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.
 //*********************************************************************************
 
-unsigned long IOService::maxCapabilityForDomainState ( IOPMPowerFlags domainState )
+IOPMPowerStateIndex
+IOService::getPowerStateForDomainFlags( IOPMPowerFlags flags )
 {
-   int i;
+       IOPMPowerStateIndex stateIndex;
 
-   if (fNumberOfPowerStates == 0 )
-   {
-       return 0;
-   }
-   for ( i = fNumberOfPowerStates - 1; i >= 0; i-- )
-   {
-       if ( (domainState & fPowerStates[i].inputPowerRequirement) ==
-                       fPowerStates[i].inputPowerRequirement )
-       {
-           return i;
-       }
-   }
-   return 0;
+       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);
 }
 
 //*********************************************************************************
-// [public virtual] initialPowerStateForDomainState
+// [public] 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.
+// Called to query the power state for the initial power transition.
 //*********************************************************************************
 
-unsigned long IOService::initialPowerStateForDomainState ( IOPMPowerFlags domainState )
+unsigned long
+IOService::initialPowerStateForDomainState( IOPMPowerFlags domainState )
 {
-    int i;
+       if (fResetPowerStateOnWake && (domainState & kIOPMRootDomainState)) {
+               // Return lowest power state for any root power domain changes
+               return kPowerStateZero;
+       }
 
-    if (fNumberOfPowerStates == 0 )
-    {
-        return 0;
-    }
-    for ( i = fNumberOfPowerStates - 1; i >= 0; i-- )
-    {
-        if ( (domainState & fPowerStates[i].inputPowerRequirement) ==
-                       fPowerStates[i].inputPowerRequirement )
-        {
-            return i;
-        }
-    }
-    return 0;
+       return getPowerStateForDomainFlags(domainState);
 }
 
 //*********************************************************************************
-// [public virtual] powerStateForDomainState
+// [public] powerStateForDomainState
 //
-// 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.
+// This method is not called from PM.
 //*********************************************************************************
 
-unsigned long IOService::powerStateForDomainState ( IOPMPowerFlags domainState )
+unsigned long
+IOService::powerStateForDomainState( IOPMPowerFlags domainState )
 {
-    int i;
-
-    if (fNumberOfPowerStates == 0 )
-    {
-        return 0;
-    }
-    for ( i = fNumberOfPowerStates - 1; i >= 0; i-- )
-    {
-        if ( (domainState & fPowerStates[i].inputPowerRequirement) ==
-                       fPowerStates[i].inputPowerRequirement )
-        {
-            return i;
-        }
-    }
-    return 0;
+       return getPowerStateForDomainFlags(domainState);
 }
 
+#ifndef __LP64__
 //*********************************************************************************
-// [public virtual] didYouWakeSystem
+// [deprecated] didYouWakeSystem
 //
 // Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-bool IOService::didYouWakeSystem  ( void )
+bool
+IOService::didYouWakeSystem( void )
 {
-    return false;
+       return false;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// [public virtual] powerStateWillChangeTo
+// [public] powerStateWillChangeTo
 //
 // Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::powerStateWillChangeTo ( IOPMPowerFlags, unsigned long, IOService * )
+IOReturn
+IOService::powerStateWillChangeTo( IOPMPowerFlags, unsigned long, IOService * )
 {
-    return kIOPMAckImplied;
+       return kIOPMAckImplied;
 }
 
 //*********************************************************************************
-// [public virtual] powerStateDidChangeTo
+// [public] powerStateDidChangeTo
 //
 // Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::powerStateDidChangeTo ( IOPMPowerFlags, unsigned long, IOService * )
+IOReturn
+IOService::powerStateDidChangeTo( IOPMPowerFlags, unsigned long, IOService * )
 {
-    return kIOPMAckImplied;
+       return kIOPMAckImplied;
 }
 
 //*********************************************************************************
-// [public virtual] powerChangeDone
+// [protected] powerChangeDone
 //
 // Called from PM work loop thread.
 // Does nothing here.  This should be implemented in a subclass policy-maker.
 //*********************************************************************************
 
-void IOService::powerChangeDone ( unsigned long )
+void
+IOService::powerChangeDone( unsigned long )
 {
 }
 
+#ifndef __LP64__
 //*********************************************************************************
-// [public virtual] newTemperature
+// [deprecated] newTemperature
 //
 // Does nothing here.  This should be implemented in a subclass driver.
 //*********************************************************************************
 
-IOReturn IOService::newTemperature ( long currentTemp, IOService * whichZone )
+IOReturn
+IOService::newTemperature( long currentTemp, IOService * whichZone )
 {
-    return IOPMNoErr;
+       return IOPMNoErr;
 }
+#endif /* !__LP64__ */
 
 //*********************************************************************************
-// [public virtual] systemWillShutdown
+// [public] systemWillShutdown
 //
 // System shutdown and restart notification.
 //*********************************************************************************
 
-void IOService::systemWillShutdown( IOOptionBits specifier )
+void
+IOService::systemWillShutdown( IOOptionBits specifier )
 {
        IOPMrootDomain * rootDomain = IOService::getPMRootDomain();
-       if (rootDomain)
+       if (rootDomain) {
                rootDomain->acknowledgeSystemWillShutdown( this );
+       }
 }
 
+// MARK: -
+// MARK: PM State Machine
+
 //*********************************************************************************
 // [private static] acquirePMRequest
 //*********************************************************************************
 
 IOPMRequest *
-IOService::acquirePMRequest( IOService * target, IOOptionBits requestType )
+IOService::acquirePMRequest( IOService * target, IOOptionBits requestType,
+    IOPMRequest * active )
 {
        IOPMRequest * request;
 
        assert(target);
 
        request = IOPMRequest::create();
-       if (request)
-       {
+       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;
 }
@@ -5143,158 +7306,153 @@ IOService::acquirePMRequest( IOService * target, IOOptionBits requestType )
 // [private static] releasePMRequest
 //*********************************************************************************
 
-void IOService::releasePMRequest( IOPMRequest * request )
+void
+IOService::releasePMRequest( IOPMRequest * request )
 {
-       if (request)
-       {
+       if (request) {
                request->reset();
                request->release();
        }
 }
 
 //*********************************************************************************
-// [private] submitPMRequest
+// [private static] submitPMRequest
 //*********************************************************************************
 
-void IOService::submitPMRequest( IOPMRequest * request )
+void
+IOService::submitPMRequest( IOPMRequest * request )
 {
        assert( request );
        assert( gIOPMReplyQueue );
        assert( gIOPMRequestQueue );
 
-       PM_TRACE("[+ %02lx] %p [%p %s] %p %p %p\n",
-               request->getType(), request,
-               request->getTarget(), request->getTarget()->getName(),
-               request->fArg0, request->fArg1, request->fArg2);
+       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->isReply())
+       if (request->isReplyType()) {
                gIOPMReplyQueue->queuePMRequest( request );
-       else
+       } else {
                gIOPMRequestQueue->queuePMRequest( request );
+       }
 }
 
-void IOService::submitPMRequest( IOPMRequest ** requests, IOItemCount count )
+void
+IOService::submitPMRequests( IOPMRequest ** requests, IOItemCount count )
 {
        assert( requests );
        assert( count > 0 );
        assert( gIOPMRequestQueue );
 
-       for (IOItemCount i = 0; i < count; i++)
-       {
+       for (IOItemCount i = 0; i < count; i++) {
                IOPMRequest * req = requests[i];
-               PM_TRACE("[+ %02lx] %p [%p %s] %p %p %p\n",
-                       req->getType(), req,
-                       req->getTarget(), req->getTarget()->getName(),
-                       req->fArg0, req->fArg1, req->fArg2);
+               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 );
 }
 
 //*********************************************************************************
-// [private] servicePMRequestQueue
+// [private] actionPMRequestQueue
+//
+// IOPMRequestQueue::checkForWork() passing a new request to the request target.
 //*********************************************************************************
 
-bool IOService::servicePMRequestQueue(
-       IOPMRequest *           request,
-       IOPMRequestQueue *      queue )
+bool
+IOService::actionPMRequestQueue(
+       IOPMRequest *       request,
+       IOPMRequestQueue *  queue )
 {
-       // Calling PM methods without PMinit() is not allowed, fail the requests.
+       bool more;
 
-       if (!initialized)
-       {
-               PM_DEBUG("[%s] %s: PM not initialized\n", getName(), __FUNCTION__);
-               goto done;
-       }
+       if (initialized) {
+               // Work queue will immediately execute the request if the per-service
+               // request queue is empty. Note pwrMgt is the target's IOServicePM.
 
-       // Create an IOPMWorkQueue on demand, when the initial PM request is
-       // received.
+               more = gIOPMWorkQueue->queuePMRequest(request, pwrMgt);
+       } else {
+               // Calling PM without PMinit() is not allowed, fail the request.
+               // Need to signal more when completing attached requests.
 
-       if (!fPMWorkQueue)
-       {
-               // Allocate and attach an IOPMWorkQueue on demand to avoid taking
-               // the work loop lock in PMinit(), which may deadlock with certain
-               // drivers / families.
-
-               fPMWorkQueue = IOPMWorkQueue::create(
-                       /* target */    this,
-                       /* Work */              OSMemberFunctionCast(IOPMWorkQueue::Action, this,
-                                                               &IOService::servicePMRequest),
-                       /* Done */              OSMemberFunctionCast(IOPMWorkQueue::Action, this,
-                                                               &IOService::retirePMRequest)
-                       );
-
-               if (fPMWorkQueue &&
-                       (gIOPMWorkLoop->addEventSource(fPMWorkQueue) != kIOReturnSuccess))
-               {
-                       PM_ERROR("[%s] %s: addEventSource failed\n",
-                               getName(), __FUNCTION__);
-                       fPMWorkQueue->release();
-                       fPMWorkQueue = 0;
-               }
+               PM_LOG("%s: PM not initialized\n", getName());
+               PM_LOG1("[- %02x] %p [%p %s] !initialized\n",
+                   request->getType(), OBFUSCATE(request),
+                   OBFUSCATE(this), getName());
 
-               if (!fPMWorkQueue)
-               {
-                       PM_ERROR("[%s] %s: not ready (type %02lx)\n",
-                               getName(), __FUNCTION__, request->getType());
-                       goto done;
+               more = gIOPMCompletionQueue->queuePMRequest(request);
+               if (more) {
+                       gIOPMWorkQueue->incrementProducerCount();
                }
        }
 
-       fPMWorkQueue->queuePMRequest(request);
-       return false;   // do not signal more
-
-done:
-       gIOPMFreeQueue->queuePMRequest( request );
-       return false;   // do not signal more
+       return more;
 }
 
 //*********************************************************************************
-// [private] servicePMFreeQueue
+// [private] actionPMCompletionQueue
 //
-// Called by IOPMFreeQueue to recycle a completed request.
+// IOPMCompletionQueue::checkForWork() passing a completed request to the
+// request target.
 //*********************************************************************************
 
-bool IOService::servicePMFreeQueue(
-       IOPMRequest *           request,
-       IOPMRequestQueue *      queue )
+bool
+IOService::actionPMCompletionQueue(
+       IOPMRequest *         request,
+       IOPMCompletionQueue * queue )
 {
-       bool more = request->hasParentRequest();
+       bool            more = (request->getNextRequest() != NULL);
+       IOPMRequest *   root = request->getRootRequest();
+
+       if (root && (root != request)) {
+               more = true;
+       }
+       if (more) {
+               gIOPMWorkQueue->incrementProducerCount();
+       }
+
        releasePMRequest( request );
        return more;
 }
 
 //*********************************************************************************
-// [private] retirePMRequest
+// [private] actionPMWorkQueueRetire
 //
-// Called by IOPMWorkQueue to retire a completed request.
+// IOPMWorkQueue::checkForWork() passing a retired request to the request target.
 //*********************************************************************************
 
-bool IOService::retirePMRequest( IOPMRequest * request, IOPMWorkQueue * queue )
+bool
+IOService::actionPMWorkQueueRetire( IOPMRequest * request, IOPMWorkQueue * queue )
 {
        assert(request && queue);
 
-       PM_TRACE("[- %02lx] %p [%p %s] State %ld, Busy %ld\n",
-               request->getType(), request, this, getName(),
-               fMachineState, gIOPMBusyCount);
-
-       // Catch requests created by PM_idle_timer_expiration().
-
-       if ((request->getType() == kIOPMRequestTypeActivityTickle) &&
-               (request->fArg1 == (void *) false))
-       {
-               // Idle timer power drop request completed.
-               // Restart the idle timer if deviceDesire can go lower, otherwise set
-               // a flag so we know to restart idle timer when deviceDesire goes up.
-
-               if (fDeviceDesire > 0)
-                       start_PM_idle_timer();
-               else
-                       fActivityTimerStopped = true;
+       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++;
+               }
        }
 
-       gIOPMFreeQueue->queuePMRequest( request );
-       return true;
+       // When the completed request is linked, tell work queue there is
+       // more work pending.
+
+       return gIOPMCompletionQueue->queuePMRequest( request );
 }
 
 //*********************************************************************************
@@ -5303,57 +7461,56 @@ bool IOService::retirePMRequest( IOPMRequest * request, IOPMWorkQueue * queue )
 // Check if machine state transition is blocked.
 //*********************************************************************************
 
-bool IOService::isPMBlocked ( IOPMRequest * request, int count )
+bool
+IOService::isPMBlocked( IOPMRequest * request, int count )
 {
-       int     reason = 0;
+       int reason = 0;
 
        do {
-               if (kIOPM_Finished == fMachineState)
+               if (kIOPM_Finished == fMachineState) {
                        break;
+               }
 
-               if (kIOPM_DriverThreadCallDone == fMachineState)
-               {
-            // 5 = kDriverCallInformPreChange
-            // 6 = kDriverCallInformPostChange
-            // 7 = kDriverCallSetPowerState
-                       if (fDriverCallBusy) reason = 5 + fDriverCallReason;
+               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)
-               {
+               if (fDriverTimer) {
                        reason = 1; break;
                }
 
                // Child or interested driver acks pending.
-               if (fHeadNotePendingAcks)
-               {
+               if (fHeadNotePendingAcks) {
                        reason = 2; break;
                }
 
                // Waiting on apps or priority power interest clients.
-               if (fResponseArray)
-               {
+               if (fResponseArray) {
                        reason = 3; break;
                }
 
                // Waiting on settle timer expiration.
-               if (fSettleTimeUS)
-               {
+               if (fSettleTimeUS) {
                        reason = 4; break;
                }
        } while (false);
 
        fWaitReason = reason;
 
-       if (reason)
-       {
-               if (count)
-               {
-                       PM_TRACE("[B %02lx] %p [%p %s] State %ld, Reason %d\n",
-                               request->getType(), request, this, getName(),
-                               fMachineState, 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;
@@ -5363,156 +7520,288 @@ bool IOService::isPMBlocked ( IOPMRequest * request, int count )
 }
 
 //*********************************************************************************
-// [private] servicePMRequest
+// [private] actionPMWorkQueueInvoke
 //
-// Service a request from our work queue.
+// IOPMWorkQueue::checkForWork() passing a request to the
+// request target for execution.
 //*********************************************************************************
 
-bool IOService::servicePMRequest( IOPMRequest * request, IOPMWorkQueue * queue )
+bool
+IOService::actionPMWorkQueueInvoke( IOPMRequest * request, IOPMWorkQueue * queue )
 {
-       bool    done = false;
-       int             loop = 0;
+       bool    done = false;
+       int     loop = 0;
 
        assert(request && queue);
 
-       while (isPMBlocked(request, loop++) == false)
-       {
-               PM_TRACE("[W %02lx] %p [%p %s] State %ld\n",
-                       request->getType(), request, this, getName(), fMachineState);
+       while (isPMBlocked(request, loop++) == false) {
+               PM_LOG1("[W %02x] %p [%p %s] state %d\n",
+                   request->getType(), OBFUSCATE(request),
+                   OBFUSCATE(this), getName(), fMachineState);
 
-               fPMRequest = request;
+               gIOPMRequest = request;
+               gIOPMWorkInvokeCount++;
 
                // Every PM machine states must be handled in one of the cases below.
 
-               switch ( fMachineState )
-               {
-                       case kIOPM_Finished:
-                               executePMRequest( request );
-                               break;
+               switch (fMachineState) {
+               case kIOPM_Finished:
+                       start_watchdog_timer();
 
-                       case kIOPM_OurChangeTellClientsPowerDown:
-                               // our change, was it vetoed?
-                               if (!fDoNotPowerDown)
-                               {
-                                       // no, we can continue
-                                       OurChangeTellClientsPowerDown();
-                               }
-                               else
-                               {
-                                       OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
-                                       PM_ERROR("%s: idle cancel\n", fName);
-                                       // yes, rescind the warning
-                                       tellNoChangeDown(fHeadNoteState);
-                                       // mark the change note un-actioned
-                                       fHeadNoteFlags |= IOPMNotDone;
-                                       // and we're done
-                                       all_done();
-                               }
-                               break;
+                       executePMRequest( request );
+                       break;
 
-                       case kIOPM_OurChangeTellPriorityClientsPowerDown:
-                               // our change, should it be acted on still?
-#if SUPPORT_IDLE_CANCEL
-                               if (fDoNotPowerDown)
-                               {
-                                       OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, fMachineState);
-                                       PM_ERROR("%s: idle revert\n", fName);
-                                       // no, tell clients we're back in the old state
+               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);
-                                       // mark the change note un-actioned
-                                       fHeadNoteFlags |= IOPMNotDone;
-                                       // and we're done
-                                       all_done();
+                               } else {
+                                       tellNoChangeDown(fHeadNotePowerState);
                                }
-                               else
-#endif
-                               {
-                                       // yes, we can continue
-                                       OurChangeTellPriorityClientsPowerDown();  
+                               // 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);
                                }
-                               break;
+                               // mark the change note un-actioned
+                               fHeadNoteChangeFlags |= kIOPMNotDone;
+                               // and we're done
+                               OurChangeFinish();
+                       } else {
+                               OurChangeTellUserPMPolicyPowerDown();
+                       }
+                       break;
 
-                       case kIOPM_OurChangeNotifyInterestedDriversWillChange:
-                               OurChangeNotifyInterestedDriversWillChange();
-                               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_OurChangeSetPowerState:
-                               OurChangeSetPowerState();
-                               break;
+               case kIOPM_OurChangeNotifyInterestedDriversWillChange:
+                       OurChangeNotifyInterestedDriversWillChange();
+                       break;
 
-                       case kIOPM_OurChangeWaitForPowerSettle:
-                               OurChangeWaitForPowerSettle();
-                               break;
+               case kIOPM_OurChangeSetPowerState:
+                       OurChangeSetPowerState();
+                       break;
 
-                       case kIOPM_OurChangeNotifyInterestedDriversDidChange:
-                               OurChangeNotifyInterestedDriversDidChange();
-                               break;
+               case kIOPM_OurChangeWaitForPowerSettle:
+                       OurChangeWaitForPowerSettle();
+                       break;
 
-                       case kIOPM_OurChangeFinish:
-                               OurChangeFinish();
-                               break;
+               case kIOPM_OurChangeNotifyInterestedDriversDidChange:
+                       OurChangeNotifyInterestedDriversDidChange();
+                       break;
 
-                       case kIOPM_ParentDownTellPriorityClientsPowerDown:
-                               ParentDownTellPriorityClientsPowerDown();
-                               break;
+               case kIOPM_OurChangeTellCapabilityDidChange:
+                       OurChangeTellCapabilityDidChange();
+                       break;
 
-                       case kIOPM_ParentDownNotifyInterestedDriversWillChange:
-                               ParentDownNotifyInterestedDriversWillChange();
-                               break;
+               case kIOPM_OurChangeFinish:
+                       OurChangeFinish();
+                       break;
 
-                       case kIOPM_ParentDownNotifyDidChangeAndAcknowledgeChange:
-                               ParentDownNotifyDidChangeAndAcknowledgeChange();
-                               break;
+               case kIOPM_ParentChangeTellPriorityClientsPowerDown:
+                       ParentChangeTellPriorityClientsPowerDown();
+                       break;
 
-                       case kIOPM_ParentDownSetPowerState:
-                               ParentDownSetPowerState();      
-                               break;
+               case kIOPM_ParentChangeNotifyInterestedDriversWillChange:
+                       ParentChangeNotifyInterestedDriversWillChange();
+                       break;
 
-                       case kIOPM_ParentDownWaitForPowerSettle:
-                               ParentDownWaitForPowerSettle();
-                               break;
+               case kIOPM_ParentChangeSetPowerState:
+                       ParentChangeSetPowerState();
+                       break;
 
-                       case kIOPM_ParentDownAcknowledgeChange:
-                               ParentDownAcknowledgeChange();
-                               break;
+               case kIOPM_ParentChangeWaitForPowerSettle:
+                       ParentChangeWaitForPowerSettle();
+                       break;
 
-                       case kIOPM_ParentUpSetPowerState:
-                               ParentUpSetPowerState();
-                               break;
+               case kIOPM_ParentChangeNotifyInterestedDriversDidChange:
+                       ParentChangeNotifyInterestedDriversDidChange();
+                       break;
 
-                       case kIOPM_ParentUpWaitForSettleTime:
-                               ParentUpWaitForSettleTime();
-                               break;
+               case kIOPM_ParentChangeTellCapabilityDidChange:
+                       ParentChangeTellCapabilityDidChange();
+                       break;
 
-                       case kIOPM_ParentUpNotifyInterestedDriversDidChange:
-                               ParentUpNotifyInterestedDriversDidChange();
-                               break;
+               case kIOPM_ParentChangeAcknowledgePowerChange:
+                       ParentChangeAcknowledgePowerChange();
+                       break;
 
-                       case kIOPM_ParentUpAcknowledgePowerChange:
-                               ParentUpAcknowledgePowerChange();
+               case kIOPM_DriverThreadCallDone:
+                       switch (fDriverCallReason) {
+                       case kDriverCallInformPreChange:
+                       case kDriverCallInformPostChange:
+                               notifyInterestedDriversDone();
                                break;
-
-                       case kIOPM_DriverThreadCallDone:
-                               if (fDriverCallReason == kDriverCallSetPowerState)
-                                       notifyControllingDriverDone();
-                               else
-                                       notifyInterestedDriversDone();
+                       case kDriverCallSetPowerState:
+                               notifyControllingDriverDone();
                                break;
-
-                       case kIOPM_NotifyChildrenDone:
-                               notifyChildrenDone();
+                       case kRootDomainInformPreChange:
+                               notifyRootDomainDone();
                                break;
-
                        default:
-                               IOPanic("servicePMWorkQueue: unknown machine state");
+                               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);
                }
 
-               fPMRequest = 0;
+               gIOPMRequest = NULL;
 
-               if (fMachineState == kIOPM_Finished)
-               {
-                       //PM_TRACE("[%s] PM   End: Request %p (type %02lx)\n",
-                       //      getName(), request, request->getType());
+               if (fMachineState == kIOPM_Finished) {
+                       stop_watchdog_timer();
                        done = true;
                        break;
                }
@@ -5525,205 +7814,423 @@ bool IOService::servicePMRequest( IOPMRequest * request, IOPMWorkQueue * queue )
 // [private] executePMRequest
 //*********************************************************************************
 
-void IOService::executePMRequest( IOPMRequest * request )
+void
+IOService::executePMRequest( IOPMRequest * request )
 {
        assert( kIOPM_Finished == fMachineState );
 
-       switch (request->getType())
-       {
-               case kIOPMRequestTypePMStop:
-                       handlePMstop( request );
-                       break;
+       switch (request->getType()) {
+       case kIOPMRequestTypePMStop:
+               handlePMstop( request );
+               break;
 
-               case kIOPMRequestTypeAddPowerChild1:
-                       addPowerChild1( request );
-                       break;
+       case kIOPMRequestTypeAddPowerChild1:
+               addPowerChild1( request );
+               break;
 
-               case kIOPMRequestTypeAddPowerChild2:
-                       addPowerChild2( request );
-                       break;
+       case kIOPMRequestTypeAddPowerChild2:
+               addPowerChild2( request );
+               break;
 
-               case kIOPMRequestTypeAddPowerChild3:
-                       addPowerChild3( request );
-                       break;
+       case kIOPMRequestTypeAddPowerChild3:
+               addPowerChild3( request );
+               break;
 
-               case kIOPMRequestTypeRegisterPowerDriver:
-                       handleRegisterPowerDriver( request );
-                       break;
+       case kIOPMRequestTypeRegisterPowerDriver:
+               handleRegisterPowerDriver( request );
+               break;
 
-               case kIOPMRequestTypeAdjustPowerState:
-                       adjustPowerState();
-                       break;
+       case kIOPMRequestTypeAdjustPowerState:
+               fAdjustPowerScheduled = false;
+               adjustPowerState();
+               break;
 
-               case kIOPMRequestTypeMakeUsable:
-                       handleMakeUsable( request );
-                       break;
+       case kIOPMRequestTypePowerDomainWillChange:
+               handlePowerDomainWillChangeTo( request );
+               break;
 
-               case kIOPMRequestTypeTemporaryPowerClamp:
-                       fClampOn = true;
-                       handleMakeUsable( request );
-                       break;
+       case kIOPMRequestTypePowerDomainDidChange:
+               handlePowerDomainDidChangeTo( request );
+               break;
 
-               case kIOPMRequestTypePowerDomainWillChange:
-                       handlePowerDomainWillChangeTo( request );
-                       break;
+       case kIOPMRequestTypeRequestPowerState:
+       case kIOPMRequestTypeRequestPowerStateOverride:
+               handleRequestPowerState( request );
+               break;
 
-               case kIOPMRequestTypePowerDomainDidChange:
-                       handlePowerDomainDidChangeTo( request );
-                       break;
+       case kIOPMRequestTypePowerOverrideOnPriv:
+       case kIOPMRequestTypePowerOverrideOffPriv:
+               handlePowerOverrideChanged( request );
+               break;
 
-               case kIOPMRequestTypeChangePowerStateTo:
-                       handleChangePowerStateTo( request );
-                       break;
+       case kIOPMRequestTypeActivityTickle:
+               handleActivityTickle( request );
+               break;
 
-               case kIOPMRequestTypeChangePowerStateToPriv:
-                       handleChangePowerStateToPriv( request );
-                       break;
+       case kIOPMRequestTypeSynchronizePowerTree:
+               handleSynchronizePowerTree( request );
+               break;
 
-               case kIOPMRequestTypePowerOverrideOnPriv:
-               case kIOPMRequestTypePowerOverrideOffPriv:
-                       handlePowerOverrideChanged( request );
-                       break;
+       case kIOPMRequestTypeSetIdleTimerPeriod:
+       {
+               fIdleTimerPeriod = (uintptr_t) request->fArg0;
+               fNextIdleTimerPeriod = fIdleTimerPeriod;
+               if ((false == fLockedFlags.PMStop) && (fIdleTimerPeriod > 0)) {
+                       restartIdleTimer();
+               }
+       }
+       break;
 
-               case kIOPMRequestTypeActivityTickle:
-                       if (request)
-                       {
-                               bool setDeviceDesire = false;
-
-                               if (request->fArg1)
-                               {
-                                       // Power rise from activity tickle.
-                    unsigned long ticklePowerState = (unsigned long) request->fArg0;
-                    if ((fDeviceDesire < ticklePowerState) &&
-                        (ticklePowerState < fNumberOfPowerStates))
-                    {
-                                               setDeviceDesire = true;
-                        fIdleTimerMinPowerState = ticklePowerState;
-                    }
-                }
-                               else if (fDeviceDesire > fIdleTimerMinPowerState)
-                               {
-                                       // Power drop from idle timer expiration.
-                                       request->fArg0 = (void *) (fDeviceDesire - 1);
-                                       setDeviceDesire = true;
-                               }
+       case kIOPMRequestTypeIgnoreIdleTimer:
+               fIdleTimerIgnored = request->fArg0 ? 1 : 0;
+               break;
+
+       case kIOPMRequestTypeQuiescePowerTree:
+               gIOPMWorkQueue->finishQuiesceRequest(request);
+               break;
+
+       default:
+               panic("executePMRequest: unknown request type %x", request->getType());
+       }
+}
+
+//*********************************************************************************
+// [private] actionPMReplyQueue
+//
+// IOPMRequestQueue::checkForWork() passing a reply-type request to the
+// request target.
+//*********************************************************************************
+
+bool
+IOService::actionPMReplyQueue( IOPMRequest * request, IOPMRequestQueue * queue )
+{
+       bool more = false;
 
-                               if (setDeviceDesire)
-                               {
-                                       // handleChangePowerStateToPriv() does not check the
-                                       // request type, as long as the args are appropriate
-                                       // for kIOPMRequestTypeChangePowerStateToPriv.
+       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;
 
-                                       request->fArg1 = (void *) false;
-                                       handleChangePowerStateToPriv( request );
+                                       OSString * name = (OSString *) request->fArg2;
+                                       getPMRootDomain()->pmStatsRecordApplicationResponse(
+                                               gIOPMStatsResponseCancel,
+                                               name ? name->getCStringNoCopy() : "", 0,
+                                               0, (int)(uintptr_t) request->fArg1, NULL);
                                }
                        }
-                       break;
 
-               default:
-                       IOPanic("executePMRequest: unknown request type");
+                       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;
+}
+
+//*********************************************************************************
+// [private] assertPMDriverCall / deassertPMDriverCall
+//*********************************************************************************
+
+bool
+IOService::assertPMDriverCall(
+       IOPMDriverCallEntry *   entry,
+       IOOptionBits            method,
+       const IOPMinformee *    inform,
+       IOOptionBits            options )
+{
+       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;
+}
+
+void
+IOService::deassertPMDriverCall( IOPMDriverCallEntry * entry )
+{
+       bool wakeup = false;
+
+       PM_LOCK();
+
+       assert( !queue_empty(&fPMDriverCallQueue));
+       queue_remove(&fPMDriverCallQueue, entry, IOPMDriverCallEntry *, link);
+       if (fLockedFlags.PMDriverCallWait) {
+               wakeup = true;
+       }
+
+       PM_UNLOCK();
+
+       if (wakeup) {
+               PM_LOCK_WAKEUP(&fPMDriverCallQueue);
+       }
+}
+
+bool
+IOService::getBlockingDriverCall(thread_t *thread, const void **callMethod)
+{
+       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;
 }
 
-//*********************************************************************************
-// [private] servicePMReplyQueue
-//*********************************************************************************
 
-bool IOService::servicePMReplyQueue( IOPMRequest * request, IOPMRequestQueue * queue )
+void
+IOService::waitForPMDriverCall( IOService * target )
 {
-       bool more = false;
-
-       assert( request && queue );
-       assert( request->isReply() );
-
-       PM_TRACE("[A %02lx] %p [%p %s] State %ld\n",
-               request->getType(), request, this, getName(), fMachineState);
+       const IOPMDriverCallEntry * entry;
+       thread_t                    thread = current_thread();
+       AbsoluteTime                deadline;
+       int                         waitResult;
+       bool                        log = true;
+       bool                        wait;
 
-       switch ( request->getType() )
-       {
-               case kIOPMRequestTypeAllowPowerChange:
-               case kIOPMRequestTypeCancelPowerChange:
-                       // Check if we are expecting this response.
-                       if (responseValid((unsigned long) request->fArg0, (int) request->fArg1))
-                       {
-                               if (kIOPMRequestTypeCancelPowerChange == request->getType())
-                                       fDoNotPowerDown = true;
+       do {
+               wait = false;
+               queue_iterate(&fPMDriverCallQueue, entry, const IOPMDriverCallEntry *, link)
+               {
+                       // Target of interested driver call
+                       if (target && (target != entry->target)) {
+                               continue;
+                       }
 
-                               if (checkForDone())
-                               {
-                                       stop_ack_timer();
-                                       if ( fResponseArray )
-                                       {
-                                               fResponseArray->release();
-                                               fResponseArray = NULL;
-                                       }
-                                       more = true;
+                       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;
                        }
-                       break;
 
-               case kIOPMRequestTypeAckPowerChange:
-                       more = handleAcknowledgePowerChange( request );
+                       wait = true;
                        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,
-                                       (UInt32) this, fDriverTimer);
-                               fDriverTimer = 0;
-                       }
-                       else if (fDriverTimer > 0)
-                       {
-                               // expected ack, stop the timer
-                               stop_ack_timer();
-
-#if LOG_SETPOWER_TIMES
-                uint64_t nsec = computeTimeDeltaNS(&fDriverCallStartTime);
-                if (nsec > LOG_SETPOWER_TIMES)
-                    PM_DEBUG("%s::setPowerState(%p, %lu -> %lu) async took %d ms\n",
-                        fName, this, fCurrentPowerState, fHeadNoteState, NS_TO_MS(nsec));
-#endif
-                               OUR_PMLog(kPMLogDriverAcknowledgeSet, (UInt32) this, fDriverTimer);
-                               fDriverTimer = 0;
-                               more = true;
-                       }
-                       else
-                       {
-                               // unexpected ack
-                               OUR_PMLog(kPMLogAcknowledgeErr4, (UInt32) this, 0);
+               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;
                        }
-                       break;
+               }
+       } while (wait);
+}
 
-               case kIOPMRequestTypeInterestChanged:
-                       handleInterestChanged( request );
-                       more = true;
-                       break;
+//*********************************************************************************
+// [private] Debug helpers
+//*********************************************************************************
 
-#if SUPPORT_IDLE_CANCEL
-               case kIOPMRequestTypeIdleCancel:
-                       if ((fMachineState == kIOPM_OurChangeTellClientsPowerDown) 
-                        || (fMachineState == kIOPM_OurChangeTellPriorityClientsPowerDown))
-                       {
-                               OUR_PMLog(kPMLogIdleCancel, (uintptr_t) this, 0);
-                               fDoNotPowerDown = true;
-                               if (fMachineState == kIOPM_OurChangeTellPriorityClientsPowerDown)
-                                       cleanClientResponses(false);
-                               more = true;
-                       }
-                       break;
-#endif
+const char *
+IOService::getIOMessageString( uint32_t msg )
+{
+#define MSG_ENTRY(x)    {(int) x, #x}
 
-               default:
-                       IOPanic("servicePMReplyQueue: unknown reply type");
-       }
+       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 }
+       };
 
-       releasePMRequest( request );
-       return more;
+       return IOFindNameForValue(msg, msgNames);
 }
 
+
+// MARK: -
+// MARK: IOPMRequest
+
 //*********************************************************************************
 // IOPMRequest Class
 //
@@ -5732,100 +8239,207 @@ bool IOService::servicePMReplyQueue( IOPMRequest * request, IOPMRequestQueue * q
 
 OSDefineMetaClassAndStructors( IOPMRequest, IOCommand );
 
-IOPMRequest * IOPMRequest::create( void )
+IOPMRequest *
+IOPMRequest::create( void )
 {
        IOPMRequest * me = OSTypeAlloc(IOPMRequest);
-       if (me && !me->init(0, kIOPMRequestTypeInvalid))
-       {
+       if (me && !me->init(NULL, kIOPMRequestTypeInvalid)) {
                me->release();
-               me = 0;
+               me = NULL;
        }
        return me;
 }
 
-bool IOPMRequest::init( IOService * target, IOOptionBits type )
+bool
+IOPMRequest::init( IOService * target, IOOptionBits type )
 {
-       if (!IOCommand::init())
+       if (!IOCommand::init()) {
                return false;
+       }
 
-       fType       = type;
-       fTarget     = target;
-       fParent     = 0;
-       fChildCount = 0;
-       fArg0 = fArg1 = fArg2 = 0;
+       fRequestType = type;
+       fTarget = target;
 
-       if (fTarget)
+       if (fTarget) {
                fTarget->retain();
+       }
+
+       // Root node and root domain requests does not prevent the power tree from
+       // becoming quiescent.
+
+       fIsQuiesceBlocker = ((fTarget != gIOPMRootNode) &&
+           (fTarget != IOService::getPMRootDomain()));
 
        return true;
 }
 
-void IOPMRequest::reset( void )
+void
+IOPMRequest::reset( void )
 {
-       assert( fChildCount == 0 );
+       assert( fWorkWaitCount == 0 );
+       assert( fFreeWaitCount == 0 );
 
-       fType = kIOPMRequestTypeInvalid;
+       detachNextRequest();
+       detachRootRequest();
 
-       if (fParent)
-       {
-               fParent->fChildCount--;
-               fParent = 0;
+       if (fCompletionAction && (fRequestType == kIOPMRequestTypeQuiescePowerTree)) {
+               // Call the completion on PM work loop context
+               fCompletionAction(fCompletionTarget, fCompletionParam);
+               fCompletionAction = NULL;
        }
 
-       if (fTarget)
-       {
+       fRequestType = kIOPMRequestTypeInvalid;
+
+       if (fTarget) {
                fTarget->release();
-               fTarget = 0;
+               fTarget = NULL;
+       }
+}
+
+bool
+IOPMRequest::attachNextRequest( IOPMRequest * next )
+{
+       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;
+}
+
+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;
+}
+
+bool
+IOPMRequest::detachRootRequest( void )
+{
+       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
+
 //*********************************************************************************
 // IOPMRequestQueue Class
 //
-// Global queues. As PM-aware drivers load and unload, their IOPMWorkQueue's are
-// created and deallocated. IOPMRequestQueue are created once and never released.
+// Global queues. Queues are created once and never released.
 //*********************************************************************************
 
 OSDefineMetaClassAndStructors( IOPMRequestQueue, IOEventSource );
 
-IOPMRequestQueue * IOPMRequestQueue::create( IOService * inOwner, Action inAction )
+IOPMRequestQueue *
+IOPMRequestQueue::create( IOService * inOwner, Action inAction )
 {
        IOPMRequestQueue * me = OSTypeAlloc(IOPMRequestQueue);
-       if (me && !me->init(inOwner, inAction))
-       {
+       if (me && !me->init(inOwner, inAction)) {
                me->release();
-               me = 0;
+               me = NULL;
        }
        return me;
 }
 
-bool IOPMRequestQueue::init( IOService * inOwner, Action inAction )
+bool
+IOPMRequestQueue::init( IOService * inOwner, Action inAction )
 {
-       if (!inAction || !IOEventSource::init(inOwner, (IOEventSourceAction)inAction))
-        return false;
+       if (!inAction || !IOEventSource::init(inOwner, (IOEventSourceAction)inAction)) {
+               return false;
+       }
 
        queue_init(&fQueue);
        fLock = IOLockAlloc();
-       return (fLock != 0);
+       return fLock != NULL;
 }
 
-void IOPMRequestQueue::free( void )
+void
+IOPMRequestQueue::free( void )
 {
-       if (fLock)
-       {
+       if (fLock) {
                IOLockFree(fLock);
-               fLock = 0;
+               fLock = NULL;
        }
        return IOEventSource::free();
 }
 
-void IOPMRequestQueue::queuePMRequest( IOPMRequest * request )
+void
+IOPMRequestQueue::queuePMRequest( IOPMRequest * request )
 {
        assert(request);
        IOLockLock(fLock);
-       queue_enter(&fQueue, request, IOPMRequest *, fCommandChain);
+       queue_enter(&fQueue, request, typeof(request), fCommandChain);
        IOLockUnlock(fLock);
-       if (workLoop) signalWorkAvailable();
+       if (workLoop) {
+               signalWorkAvailable();
+       }
 }
 
 void
@@ -5835,29 +8449,37 @@ IOPMRequestQueue::queuePMRequestChain( IOPMRequest ** requests, IOItemCount coun
 
        assert(requests && count);
        IOLockLock(fLock);
-       while (count--)
-       {
+       while (count--) {
                next = *requests;
                requests++;
-               queue_enter(&fQueue, next, IOPMRequest *, fCommandChain);
+               queue_enter(&fQueue, next, typeof(next), fCommandChain);
        }
        IOLockUnlock(fLock);
-       if (workLoop) signalWorkAvailable();
+       if (workLoop) {
+               signalWorkAvailable();
+       }
 }
 
-bool IOPMRequestQueue::checkForWork( void )
+bool
+IOPMRequestQueue::checkForWork( void )
 {
-    Action                     dqAction = (Action) action;
-       IOPMRequest *   request;
-       IOService *             target;
-       bool                    more = false;
+       Action          dqAction = (Action) action;
+       IOPMRequest *   request;
+       IOService *     target;
+       int             dequeueCount = 0;
+       bool            more = false;
 
        IOLockLock( fLock );
 
-       while (!queue_empty(&fQueue))
-       {
-               queue_remove_first( &fQueue, request, IOPMRequest *, fCommandChain );           
-               IOLockUnlock( 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 );
@@ -5868,79 +8490,326 @@ bool IOPMRequestQueue::checkForWork( void )
        return more;
 }
 
-void IOPMRequestQueue::signalWorkAvailable( void )
-{
-       IOEventSource::signalWorkAvailable();
-}
+// MARK: -
+// MARK: IOPMWorkQueue
 
 //*********************************************************************************
 // IOPMWorkQueue Class
 //
-// Every object in the power plane that has handled a PM request, will have an
-// instance of IOPMWorkQueue allocated for it.
+// Queue of IOServicePM objects, each with a queue of IOPMRequest sharing the
+// same target.
 //*********************************************************************************
 
 OSDefineMetaClassAndStructors( IOPMWorkQueue, IOEventSource );
 
 IOPMWorkQueue *
-IOPMWorkQueue::create( IOService * inOwner, Action work, Action retire )
+IOPMWorkQueue::create( IOService * inOwner, Action invoke, Action retire )
 {
        IOPMWorkQueue * me = OSTypeAlloc(IOPMWorkQueue);
-       if (me && !me->init(inOwner, work, retire))
-       {
+       if (me && !me->init(inOwner, invoke, retire)) {
                me->release();
-               me = 0;
+               me = NULL;
        }
        return me;
 }
 
-bool IOPMWorkQueue::init( IOService * inOwner, Action work, Action retire )
+bool
+IOPMWorkQueue::init( IOService * inOwner, Action invoke, Action retire )
 {
-       if (!work || !retire ||
-               !IOEventSource::init(inOwner, (IOEventSourceAction)0))
+       if (!invoke || !retire ||
+           !IOEventSource::init(inOwner, (IOEventSourceAction)NULL)) {
                return false;
+       }
 
        queue_init(&fWorkQueue);
 
-       fWorkAction   = work;
-       fRetireAction = retire;
+       fInvokeAction  = invoke;
+       fRetireAction  = retire;
+       fConsumerCount = fProducerCount = 0;
 
        return true;
 }
 
-void IOPMWorkQueue::queuePMRequest( IOPMRequest * request )
+bool
+IOPMWorkQueue::queuePMRequest( IOPMRequest * request, IOServicePM * pwrMgt )
 {
+       queue_head_t *  requestQueue;
+       bool            more  = false;
+       bool            empty;
+
        assert( request );
-       assert( onThread() );
+       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;
+}
+
+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;
+}
+
+void
+IOPMWorkQueue::signalWorkAvailable( void )
+{
+       fProducerCount++;
+       IOEventSource::signalWorkAvailable();
+}
 
-       gIOPMBusyCount++;
-       queue_enter(&fWorkQueue, request, IOPMRequest *, fCommandChain);
-       checkForWork();
+void
+IOPMWorkQueue::incrementProducerCount( void )
+{
+       fProducerCount++;
 }
 
-bool IOPMWorkQueue::checkForWork( void )
+void
+IOPMWorkQueue::attachQuiesceRequest( IOPMRequest * quiesceRequest )
 {
-       IOPMRequest *   request;
-       IOService *             target = (IOService *) owner;
-       bool                    done;
+       IOServicePM *   entry;
+       IOPMRequest *   request;
+
+       if (queue_empty(&fWorkQueue)) {
+               return;
+       }
 
-       while (!queue_empty(&fWorkQueue))
+       queue_iterate(&fWorkQueue, entry, typeof(entry), WorkChain)
        {
-               request = (IOPMRequest *) queue_first(&fWorkQueue);
-               assert(request->getTarget() == target);
-               if (request->hasChildRequest()) break;
-               done = (*fWorkAction)( target, request, this );
-               if (!done) break;
+               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);
+                       }
+               }
+       }
+}
 
-               assert(gIOPMBusyCount > 0);
-               if (gIOPMBusyCount) gIOPMBusyCount--;
-               queue_remove_first(&fWorkQueue, request, IOPMRequest *, fCommandChain);
-               (*fRetireAction)( target, request, this );
+void
+IOPMWorkQueue::finishQuiesceRequest( IOPMRequest * quiesceRequest )
+{
+       if (fQuiesceRequest && (quiesceRequest == fQuiesceRequest) &&
+           (fQuiesceStartTime != 0)) {
+               fInvokeAction = NULL;
+               fQuiesceFinishTime = mach_absolute_time();
        }
+}
 
-       return false;
+// MARK: -
+// MARK: IOPMCompletionQueue
+
+//*********************************************************************************
+// IOPMCompletionQueue Class
+//*********************************************************************************
+
+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;
+       }
+
+       queue_init(&fQueue);
+       return true;
+}
+
+bool
+IOPMCompletionQueue::queuePMRequest( IOPMRequest * request )
+{
+       bool more;
+
+       assert(request);
+       // unblock dependent request
+       more = request->detachNextRequest();
+       queue_enter(&fQueue, request, typeof(request), fCommandChain);
+       return more;
+}
+
+bool
+IOPMCompletionQueue::checkForWork( void )
+{
+       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
+
 OSDefineMetaClassAndStructors(IOServicePM, OSObject)
 
 //*********************************************************************************
@@ -5950,41 +8819,165 @@ OSDefineMetaClassAndStructors(IOServicePM, OSObject)
 //*********************************************************************************
 
 static void
-setPMProperty( OSDictionary * dict, const char * key, unsigned long value )
+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();
-    }
+       OSNumber * num = OSNumber::withNumber(value, sizeof(value) * 8);
+       if (num) {
+               dict->setObject(key, num);
+               num->release();
+       }
 }
 
-bool IOServicePM::serialize( OSSerialize * s ) const
+IOReturn
+IOServicePM::gatedSerialize( OSSerialize * s  ) const
 {
-       OSDictionary *  dict;
-       bool                    ok = false;
+       OSDictionary *  dict;
+       bool            ok = false;
+       int             powerClamp = -1;
+       int             dictSize = 6;
 
-       dict = OSDictionary::withCapacity(8);
-       if (dict)
-       {
-        setPMProperty( dict, "CurrentPowerState", CurrentPowerState );
-        if (DesiredPowerState != CurrentPowerState)
-            setPMProperty( dict, "DesiredPowerState", DesiredPowerState );
-        if (kIOPM_Finished != MachineState)
-            setPMProperty( dict, "MachineState", MachineState );
-        if (ChildrenDesire)
-            setPMProperty( dict, "ChildrenPowerState", ChildrenDesire );
-        if (DeviceDesire)
-            setPMProperty( dict, "DeviceChangePowerState", DeviceDesire );
-        if (DriverDesire)
-            setPMProperty( dict, "DriverChangePowerState", DriverDesire );
-        if (DeviceOverrides)
-            dict->setObject( "PowerOverrideOn", kOSBooleanTrue );
+       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;
+       return ok ? kIOReturnSuccess : kIOReturnNoMemory;
+}
+
+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;
+}
+
+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;
+
+       assert(event < KDBG_CODE_MAX);
+       assert((eventFunc & ~KDBG_FUNC_MASK) == 0);
+
+       // 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)));
 }