iokit/Kernel/IOPMPowerStateQueue.cpp

   1 /*
   2  * Copyright (c) 2001-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include "IOPMPowerStateQueue.h"
  25 #undef super
  26 #define super IOEventSource
  27 OSDefineMetaClassAndStructors(IOPMPowerStateQueue, IOEventSource);
  28
  29 IOPMPowerStateQueue *IOPMPowerStateQueue::PMPowerStateQueue(OSObject *inOwner)
  30 {
  31     IOPMPowerStateQueue     *me = new IOPMPowerStateQueue;
  32
  33     if(me && !me->init(inOwner, 0) )
  34     {
  35         me->release();
  36         return NULL;
  37     }
  38
  39     return me;
  40 }
  41
  42 bool IOPMPowerStateQueue::init(OSObject *owner, Action action)
  43 {
  44     if(!(super::init(owner, (IOEventSource::Action) action))) return false;
  45
  46     // Queue of powerstate changes
  47     changes = NULL;
  48
  49     return true;
  50 }
  51
  52
  53 bool IOPMPowerStateQueue::unIdleOccurred(IOService *inTarget, unsigned long inState)
  54 {
  55     PowerChangeEntry             *new_one = NULL;
  56
  57     new_one = (PowerChangeEntry *)IOMalloc(sizeof(PowerChangeEntry));
  58     if(!new_one) return false;
  59
  60     new_one->actionType = IOPMPowerStateQueue::kUnIdle;
  61     new_one->state = inState;
  62     new_one->target = inTarget;
  63
  64     // Change to queue
  65     OSEnqueueAtomic((void **)&changes, (void *)new_one, 0);
  66
  67     signalWorkAvailable();
  68
  69     return true;
  70 }
  71
  72 // checkForWork() is called in a gated context
  73 bool IOPMPowerStateQueue::checkForWork()
  74 {
  75     PowerChangeEntry            *theNode;
  76     int                         theState;
  77     IOService                   *theTarget;
  78     UInt16                      theAction;
  79
  80     // Dequeue and process the state change request
  81     if((theNode = (PowerChangeEntry *)OSDequeueAtomic((void **)&changes, 0)))
  82     {
  83         theState = theNode->state;
  84         theTarget = theNode->target;
  85         theAction = theNode->actionType;
  86         IOFree((void *)theNode, sizeof(PowerChangeEntry));
  87
  88         switch (theAction)
  89         {
  90             case kUnIdle:
  91                 theTarget->command_received(theState, 0, 0, 0);
  92                 break;
  93         }
  94     }
  95
  96     // Return true if there's more work to be done
  97     if(changes) return true;
  98     else return false;
  99 }