iokit/Kernel/IOPMPowerStateQueue.cpp

   1 /*
   2  * Copyright (c) 2001-2002 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
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  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30
  31 #include "IOPMPowerStateQueue.h"
  32 #undef super
  33 #define super IOEventSource
  34 OSDefineMetaClassAndStructors(IOPMPowerStateQueue, IOEventSource);
  35
  36 IOPMPowerStateQueue *IOPMPowerStateQueue::PMPowerStateQueue(OSObject *inOwner)
  37 {
  38     IOPMPowerStateQueue     *me = new IOPMPowerStateQueue;
  39
  40     if(me && !me->init(inOwner, 0) )
  41     {
  42         me->release();
  43         return NULL;
  44     }
  45
  46     return me;
  47 }
  48
  49 bool IOPMPowerStateQueue::init(OSObject *owner, Action action)
  50 {
  51     if(!(super::init(owner, (IOEventSource::Action) action))) return false;
  52
  53     // Queue of powerstate changes
  54     changes = NULL;
  55
  56     return true;
  57 }
  58
  59
  60 bool IOPMPowerStateQueue::unIdleOccurred(IOService *inTarget, unsigned long inState)
  61 {
  62     PowerChangeEntry             *new_one = NULL;
  63
  64     new_one = (PowerChangeEntry *)IOMalloc(sizeof(PowerChangeEntry));
  65     if(!new_one) return false;
  66
  67     new_one->actionType = IOPMPowerStateQueue::kUnIdle;
  68     new_one->state = inState;
  69     new_one->target = inTarget;
  70
  71     // Change to queue
  72     OSEnqueueAtomic((void **)&changes, (void *)new_one, 0);
  73
  74     signalWorkAvailable();
  75
  76     return true;
  77 }
  78
  79 // checkForWork() is called in a gated context
  80 bool IOPMPowerStateQueue::checkForWork()
  81 {
  82     PowerChangeEntry            *theNode;
  83     int                         theState;
  84     IOService                   *theTarget;
  85     UInt16                      theAction;
  86
  87     // Dequeue and process the state change request
  88     if((theNode = (PowerChangeEntry *)OSDequeueAtomic((void **)&changes, 0)))
  89     {
  90         theState = theNode->state;
  91         theTarget = theNode->target;
  92         theAction = theNode->actionType;
  93         IOFree((void *)theNode, sizeof(PowerChangeEntry));
  94
  95         switch (theAction)
  96         {
  97             case kUnIdle:
  98                 theTarget->command_received(theState, 0, 0, 0);
  99                 break;
 100         }
 101     }
 102
 103     // Return true if there's more work to be done
 104     if(changes) return true;
 105     else return false;
 106 }