iokit/Kernel/IODMAEventSource.cpp

   1 /*
   2  * Copyright (c) 1998-2000 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
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   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,
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  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
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  27  */
  28
  29 #include <IOKit/IODMAEventSource.h>
  30 #include <IOKit/IOService.h>
  31
  32 #include "IOKitKernelInternal.h"
  33
  34
  35 #define super IOEventSource
  36 OSDefineMetaClassAndStructors(IODMAEventSource, IOEventSource);
  37
  38 bool IODMAEventSource::init(OSObject *inOwner,
  39                             IOService *inProvider,
  40                             Action inCompletion,
  41                             Action inNotification,
  42                             UInt32 inDMAIndex)
  43 {
  44   IOReturn result;
  45
  46   if (!super::init(inOwner)) return false;
  47
  48   if (inProvider == 0) return false;
  49
  50   dmaProvider = inProvider;
  51   dmaIndex = 0xFFFFFFFF;
  52   dmaCompletionAction = inCompletion;
  53   dmaNotificationAction = inNotification;
  54
  55   dmaController = IODMAController::getController(dmaProvider, inDMAIndex);
  56   if (dmaController == 0) return false;
  57   dmaController->retain();
  58
  59   result = dmaController->initDMAChannel(dmaProvider, this, &dmaIndex, inDMAIndex);
  60   if (result != kIOReturnSuccess) return false;
  61
  62   queue_init(&dmaCommandsCompleted);
  63   dmaCommandsCompletedLock = IOSimpleLockAlloc();
  64
  65   return true;
  66 }
  67
  68 IODMAEventSource *IODMAEventSource::dmaEventSource(OSObject *inOwner,
  69                                                    IOService *inProvider,
  70                                                    Action inCompletion,
  71                                                    Action inNotification,
  72                                                    UInt32 inDMAIndex)
  73 {
  74   IODMAEventSource *dmaES = new IODMAEventSource;
  75
  76   if (dmaES && !dmaES->init(inOwner, inProvider, inCompletion, inNotification, inDMAIndex)) {
  77     dmaES->release();
  78     return 0;
  79   }
  80
  81   return dmaES;
  82 }
  83
  84 IOReturn IODMAEventSource::startDMACommand(IODMACommand *dmaCommand, IODirection direction, IOByteCount byteCount, IOByteCount byteOffset)
  85 {
  86   IOReturn result;
  87
  88   if ((dmaController == 0) || (dmaIndex == 0xFFFFFFFF)) return kIOReturnError;
  89
  90   if (dmaSynchBusy) return kIOReturnBusy;
  91
  92   if (dmaCompletionAction == 0) dmaSynchBusy = true;
  93
  94   result = dmaController->startDMACommand(dmaIndex, dmaCommand, direction, byteCount, byteOffset);
  95
  96   if (result != kIOReturnSuccess) {
  97     dmaSynchBusy = false;
  98     return result;
  99   }
 100
 101   while (dmaSynchBusy) sleepGate(&dmaSynchBusy, THREAD_UNINT);
 102
 103   return kIOReturnSuccess;
 104 }
 105
 106 IOReturn IODMAEventSource::stopDMACommand(bool flush, uint64_t timeout)
 107 {
 108   if ((dmaController == 0) || (dmaIndex == 0xFFFFFFFF)) return kIOReturnError;
 109
 110   return dmaController->stopDMACommand(dmaIndex, flush, timeout);
 111 }
 112
 113
 114 IOReturn IODMAEventSource::queryDMACommand(IODMACommand **dmaCommand, IOByteCount *transferCount, bool waitForIdle)
 115 {
 116   if ((dmaController == 0) || (dmaIndex == 0xFFFFFFFF)) return kIOReturnError;
 117
 118   return dmaController->queryDMACommand(dmaIndex, dmaCommand, transferCount, waitForIdle);
 119 }
 120
 121
 122 IOByteCount IODMAEventSource::getFIFODepth()
 123 {
 124   if ((dmaController == 0) || (dmaIndex == 0xFFFFFFFF)) return kIOReturnError;
 125
 126   return dmaController->getFIFODepth(dmaIndex);
 127 }
 128
 129
 130 // protected
 131
 132 bool IODMAEventSource::checkForWork(void)
 133 {
 134   IODMACommand     *dmaCommand = NULL;
 135   bool work, again;
 136
 137   IOSimpleLockLock(dmaCommandsCompletedLock);
 138   work = !queue_empty(&dmaCommandsCompleted);
 139   if (work) {
 140     queue_remove_first(&dmaCommandsCompleted, dmaCommand, IODMACommand *, fCommandChain);
 141     again = !queue_empty(&dmaCommandsCompleted);
 142   } else {
 143     again = false;
 144   }
 145   IOSimpleLockUnlock(dmaCommandsCompletedLock);
 146
 147   if (work) {
 148     (*dmaCompletionAction)(owner, this, dmaCommand, dmaCommand->reserved->fStatus, dmaCommand->reserved->fActualByteCount);
 149   }
 150
 151   return again;
 152 }
 153
 154 void IODMAEventSource::completeDMACommand(IODMACommand *dmaCommand)
 155 {
 156   if (dmaCompletionAction != 0) {
 157     IOSimpleLockLock(dmaCommandsCompletedLock);
 158     queue_enter(&dmaCommandsCompleted, dmaCommand, IODMACommand *, fCommandChain);
 159     IOSimpleLockUnlock(dmaCommandsCompletedLock);
 160
 161     signalWorkAvailable();
 162   } else {
 163     dmaSynchBusy = false;
 164     wakeupGate(&dmaSynchBusy, true);
 165   }
 166 }
 167
 168 void IODMAEventSource::notifyDMACommand(IODMACommand *dmaCommand, IOReturn status, IOByteCount actualByteCount)
 169 {
 170   dmaCommand->reserved->fStatus = status;
 171   dmaCommand->reserved->fActualByteCount = actualByteCount;
 172
 173   if (dmaNotificationAction != 0) (*dmaNotificationAction)(owner, this, dmaCommand, status, actualByteCount);
 174 }