iokit/Kernel/IOPMPowerStateQueue.cpp

   1 /*
   2  * Copyright (c) 2001-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22
  23 #include "IOPMPowerStateQueue.h"
  24 #undef super
  25 #define super IOEventSource
  26 OSDefineMetaClassAndStructors(IOPMPowerStateQueue, IOEventSource);
  27
  28 IOPMPowerStateQueue *IOPMPowerStateQueue::PMPowerStateQueue(OSObject *inOwner)
  29 {
  30     IOPMPowerStateQueue     *me = new IOPMPowerStateQueue;
  31
  32     if(me && !me->init(inOwner, 0) )
  33     {
  34         me->release();
  35         return NULL;
  36     }
  37
  38     return me;
  39 }
  40
  41 bool IOPMPowerStateQueue::init(OSObject *owner, Action action)
  42 {
  43     if(!(super::init(owner, (IOEventSource::Action) action))) return false;
  44
  45     // Queue of powerstate changes
  46     changes = NULL;
  47
  48     return true;
  49 }
  50
  51
  52 bool IOPMPowerStateQueue::unIdleOccurred(IOService *inTarget, unsigned long inState)
  53 {
  54     PowerChangeEntry             *new_one = NULL;
  55
  56     new_one = (PowerChangeEntry *)IOMalloc(sizeof(PowerChangeEntry));
  57     if(!new_one) return false;
  58
  59     new_one->actionType = IOPMPowerStateQueue::kUnIdle;
  60     new_one->state = inState;
  61     new_one->target = inTarget;
  62
  63     // Change to queue
  64     OSEnqueueAtomic((void **)&changes, (void *)new_one, 0);
  65
  66     signalWorkAvailable();
  67
  68     return true;
  69 }
  70
  71 // checkForWork() is called in a gated context
  72 bool IOPMPowerStateQueue::checkForWork()
  73 {
  74     PowerChangeEntry            *theNode;
  75     int                         theState;
  76     IOService                   *theTarget;
  77     UInt16                      theAction;
  78
  79     // Dequeue and process the state change request
  80     if((theNode = (PowerChangeEntry *)OSDequeueAtomic((void **)&changes, 0)))
  81     {
  82         theState = theNode->state;
  83         theTarget = theNode->target;
  84         theAction = theNode->actionType;
  85         IOFree((void *)theNode, sizeof(PowerChangeEntry));
  86
  87         switch (theAction)
  88         {
  89             case kUnIdle:
  90                 theTarget->command_received(theState, 0, 0, 0);
  91                 break;
  92         }
  93     }
  94
  95     // Return true if there's more work to be done
  96     if(changes) return true;
  97     else return false;
  98 }