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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 }
175