1 /* 2 ** 3 ** Copyright 2011, The Android Open Source Project 4 ** 5 ** Licensed under the Apache License, Version 2.0 (the "License"); 6 ** you may not use this file except in compliance with the License. 7 ** You may obtain a copy of the License at 8 ** 9 ** http://www.apache.org/licenses/LICENSE-2.0 10 ** 11 ** Unless required by applicable law or agreed to in writing, software 12 ** distributed under the License is distributed on an "AS IS" BASIS, 13 ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 ** See the License for the specific language governing permissions and 15 ** limitations under the License. 16 */ 17 18 #ifndef ANDROID_AUDIO_OUTPUT_H 19 #define ANDROID_AUDIO_OUTPUT_H 20 21 #include <semaphore.h> 22 #include <tinyalsa/asoundlib.h> 23 #include <utils/String16.h> 24 #include <utils/String8.h> 25 #include <utils/threads.h> 26 #include <utils/Vector.h> 27 28 #include "LinearTransform.h" 29 30 namespace android { 31 32 class AudioStreamOut; 33 34 class AudioOutput : public RefBase { 35 public: 36 37 // Audio ouput state machine states. 38 enum State { 39 // Ouput not yet started or synchronized. 40 OUT_OF_SYNC, 41 42 // Silence primed to output to start DMA. 43 PRIMED, 44 45 // DMA started, ready to align to other inputs. 46 DMA_START, 47 48 // DMA active. 49 ACTIVE, 50 51 // Fatal, unrecoverable error. 52 FATAL, 53 }; 54 55 AudioOutput(const char* alsa_name, 56 enum pcm_format alsa_pcm_format); 57 virtual ~AudioOutput(); 58 59 virtual status_t initCheck(); 60 virtual status_t setupForStream(const AudioStreamOut& stream) = 0; 61 62 // State machine transition functions. 63 State getState() { return mState; }; 64 bool hasFatalError() { return mState == FATAL; } 65 66 // Prime data to output device, go to PRIMED state. 67 void primeOutput(bool hasActiveOutputs); 68 69 // Adjust for write timestamp difference, go to ACTIVE state. 70 void adjustDelay(int32_t nFrames); 71 72 // Send one chunk of data to ALSA, if state machine permits. This is called 73 // for every chunk sent down, regardless of the state of the output. 74 void processOneChunk(const uint8_t* data, size_t len, 75 bool hasActiveOutputs, audio_format_t format); 76 77 status_t getNextWriteTimestamp(int64_t* timestamp, 78 bool* discon); 79 bool getLastNextWriteTSValid() const; 80 int64_t getLastNextWriteTS() const; 81 82 uint32_t getExternalDelay_uSec() const; 83 void setExternalDelay_uSec(uint32_t delay); 84 void setDelayComp_uSec(uint32_t delay_usec); 85 86 void setVolume(float vol); 87 void setMute(bool mute); 88 void setOutputIsFixed(bool fixed); 89 void setFixedOutputLevel(float level); 90 91 float getVolume() const { return mVolume; } 92 bool getMute() const { return mMute; } 93 bool getOutputIsFixed() const { return mOutputFixed; } 94 float getFixedOutputLevel() const { return mFixedLvl; } 95 96 int getHardwareTimestamp(unsigned int *pAvail, 97 struct timespec *pTimestamp); 98 uint32_t getKernelBufferSize() { return mFramesPerChunk * mBufferChunks; } 99 100 virtual void dump(String8& result) = 0; 101 102 virtual const char* getOutputName() = 0; 103 virtual uint32_t devMask() const = 0; 104 105 virtual void cleanupResources(); 106 107 static const uint32_t kMaxDelayCompensationMSec; 108 static const uint32_t kPrimeTimeoutChunks; 109 110 protected: 111 112 void pushSilence(uint32_t nFrames); 113 114 virtual void openPCMDevice(); 115 virtual void reset(); 116 virtual status_t getDMAStartData(int64_t* dma_start_time, 117 int64_t* frames_queued_to_driver); 118 void doPCMWrite(const uint8_t* data, size_t len, audio_format_t format); 119 void setupInternal(); 120 121 // Current state machine state. 122 State mState; 123 124 // Output format 125 uint32_t mFramesPerChunk; 126 uint32_t mFramesPerSec; 127 uint32_t mBufferChunks; 128 uint32_t mChannelCnt; 129 const char* mALSAName; 130 enum pcm_format mALSAFormat; 131 132 // These numbers are relative to the ALSA output. 133 uint32_t mBytesPerSample; 134 uint32_t mBytesPerFrame; 135 uint32_t mBytesPerChunk; 136 size_t mStagingSize; 137 void* mStagingBuf; 138 size_t mSilenceSize; 139 void* mSilenceBuf; 140 141 // Get next write time stuff. 142 bool mLastNextWriteTimeValid; 143 int64_t mLastNextWriteTime; 144 int64_t mLastDMAStartTime; 145 146 // External delay compensation. 147 uint32_t mMaxDelayCompFrames; 148 uint32_t mExternalDelayUSec; 149 uint32_t mExternalDelayLocalTicks; 150 151 LinearTransform mFramesToLocalTime; 152 153 // ALSA device stuff. 154 Mutex mDeviceLock; 155 struct pcm* mDevice; 156 int mDeviceExtFd; 157 int mALSACardID; 158 uint64_t mFramesQueuedToDriver; 159 uint32_t mPrimeTimeoutChunks; 160 161 // reduce log spew 162 bool mReportedWriteFail; 163 164 // Volume stuff 165 Mutex mVolumeLock; 166 float mVolume; 167 float mFixedLvl; 168 bool mMute; 169 bool mOutputFixed; 170 bool mVolParamsDirty; 171 virtual void applyPendingVolParams() = 0; 172 }; 173 174 typedef Vector< sp<AudioOutput> > AudioOutputList; 175 176 } // namespace android 177 #endif // ANDROID_AUDIO_OUTPUT_H 178
