iokit/Kernel/IOPMPowerStateQueue.cpp

   1 /*
   2  * Copyright (c) 2001-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25
  26 #include "IOPMPowerStateQueue.h"
  27 #undef super
  28 #define super IOEventSource
  29 OSDefineMetaClassAndStructors(IOPMPowerStateQueue, IOEventSource);
  30
  31 IOPMPowerStateQueue *IOPMPowerStateQueue::PMPowerStateQueue(OSObject *inOwner)
  32 {
  33     IOPMPowerStateQueue     *me = new IOPMPowerStateQueue;
  34
  35     if(me && !me->init(inOwner, 0) )
  36     {
  37         me->release();
  38         return NULL;
  39     }
  40
  41     return me;
  42 }
  43
  44 bool IOPMPowerStateQueue::init(OSObject *owner, Action action)
  45 {
  46     if(!(super::init(owner, (IOEventSource::Action) action))) return false;
  47
  48     // Queue of powerstate changes
  49     changes = NULL;
  50
  51     return true;
  52 }
  53
  54
  55 bool IOPMPowerStateQueue::unIdleOccurred(IOService *inTarget, unsigned long inState)
  56 {
  57     PowerChangeEntry             *new_one = NULL;
  58
  59     new_one = (PowerChangeEntry *)IOMalloc(sizeof(PowerChangeEntry));
  60     if(!new_one) return false;
  61
  62     new_one->actionType = IOPMPowerStateQueue::kUnIdle;
  63     new_one->state = inState;
  64     new_one->target = inTarget;
  65
  66     // Change to queue
  67     OSEnqueueAtomic((void **)&changes, (void *)new_one, 0);
  68
  69     signalWorkAvailable();
  70
  71     return true;
  72 }
  73
  74 // checkForWork() is called in a gated context
  75 bool IOPMPowerStateQueue::checkForWork()
  76 {
  77     PowerChangeEntry            *theNode;
  78     int                         theState;
  79     IOService                   *theTarget;
  80     UInt16                      theAction;
  81
  82     // Dequeue and process the state change request
  83     if((theNode = (PowerChangeEntry *)OSDequeueAtomic((void **)&changes, 0)))
  84     {
  85         theState = theNode->state;
  86         theTarget = theNode->target;
  87         theAction = theNode->actionType;
  88         IOFree((void *)theNode, sizeof(PowerChangeEntry));
  89
  90         switch (theAction)
  91         {
  92             case kUnIdle:
  93                 theTarget->command_received(theState, 0, 0, 0);
  94                 break;
  95         }
  96     }
  97
  98     // Return true if there's more work to be done
  99     if(changes) return true;
 100     else return false;
 101 }