iokit/Kernel/IOPMPowerStateQueue.cpp

   1 /*
   2  * Copyright (c) 2001-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #include "IOPMPowerStateQueue.h"
  30 #undef super
  31 #define super IOEventSource
  32 OSDefineMetaClassAndStructors(IOPMPowerStateQueue, IOEventSource);
  33
  34 IOPMPowerStateQueue *IOPMPowerStateQueue::PMPowerStateQueue(OSObject *inOwner)
  35 {
  36     IOPMPowerStateQueue     *me = new IOPMPowerStateQueue;
  37
  38     if(me && !me->init(inOwner, 0) )
  39     {
  40         me->release();
  41         return NULL;
  42     }
  43
  44     return me;
  45 }
  46
  47 bool IOPMPowerStateQueue::init(OSObject *owner, Action action)
  48 {
  49     if(!(super::init(owner, (IOEventSource::Action) action))) return false;
  50
  51     // Queue of powerstate changes
  52     changes = NULL;
  53
  54     return true;
  55 }
  56
  57
  58 bool IOPMPowerStateQueue::unIdleOccurred(IOService *inTarget, unsigned long inState)
  59 {
  60     PowerChangeEntry             *new_one = NULL;
  61
  62     new_one = (PowerChangeEntry *)IOMalloc(sizeof(PowerChangeEntry));
  63     if(!new_one) return false;
  64
  65     new_one->actionType = IOPMPowerStateQueue::kUnIdle;
  66     new_one->state = inState;
  67     new_one->target = inTarget;
  68
  69     // Change to queue
  70     OSEnqueueAtomic((void **)&changes, (void *)new_one, 0);
  71
  72     signalWorkAvailable();
  73
  74     return true;
  75 }
  76
  77 // checkForWork() is called in a gated context
  78 bool IOPMPowerStateQueue::checkForWork()
  79 {
  80     PowerChangeEntry            *theNode;
  81     int                         theState;
  82     IOService                   *theTarget;
  83     UInt16                      theAction;
  84
  85     // Dequeue and process the state change request
  86     if((theNode = (PowerChangeEntry *)OSDequeueAtomic((void **)&changes, 0)))
  87     {
  88         theState = theNode->state;
  89         theTarget = theNode->target;
  90         theAction = theNode->actionType;
  91         IOFree((void *)theNode, sizeof(PowerChangeEntry));
  92
  93         switch (theAction)
  94         {
  95             case kUnIdle:
  96                 theTarget->command_received(theState, 0, 0, 0);
  97                 break;
  98         }
  99     }
 100
 101     // Return true if there's more work to be done
 102     if(changes) return true;
 103     else return false;
 104 }