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/LinearTransform.h> 24 #include <utils/String16.h> 25 #include <utils/String8.h> 26 #include <utils/threads.h> 27 #include <utils/Vector.h> 28 29 namespace android { 30 31 class AudioStreamOut; 32 33 class AudioOutput : public RefBase { 34 public: 35 36 // Audio ouput state machine states. 37 enum State { 38 // Ouput not yet started or synchronized. 39 OUT_OF_SYNC, 40 41 // Silence primed to output to start DMA. 42 PRIMED, 43 44 // DMA started, ready to align to other inputs. 45 DMA_START, 46 47 // DMA active. 48 ACTIVE, 49 50 // Fatal, unrecoverable error. 51 FATAL, 52 }; 53 54 AudioOutput(const char* alsa_name, 55 enum pcm_format alsa_pcm_format); 56 virtual ~AudioOutput(); 57 58 virtual status_t initCheck(); 59 virtual status_t setupForStream(const AudioStreamOut& stream) = 0; 60 61 // State machine transition functions. 62 State getState() { return mState; }; 63 bool hasFatalError() { return mState == FATAL; } 64 65 // Prime data to output device, go to PRIMED state. 66 void primeOutput(bool hasActiveOutputs); 67 68 // Adjust for write timestamp difference, go to ACTIVE state. 69 void adjustDelay(int32_t nFrames); 70 71 // Send one chunk of data to ALSA, if state machine permits. This is called 72 // for every chunk sent down, regardless of the state of the output. 73 void processOneChunk(const uint8_t* data, size_t len, 74 bool hasActiveOutputs); 75 76 status_t getNextWriteTimestamp(int64_t* timestamp, 77 bool* discon); 78 bool getLastNextWriteTSValid() const; 79 int64_t getLastNextWriteTS() const; 80 81 uint32_t getExternalDelay_uSec() const; 82 void setExternalDelay_uSec(uint32_t delay); 83 void setDelayComp_uSec(uint32_t delay_usec); 84 85 void setVolume(float vol); 86 void setMute(bool mute); 87 void setOutputIsFixed(bool fixed); 88 void setFixedOutputLevel(float level); 89 90 float getVolume() const { return mVolume; } 91 bool getMute() const { return mMute; } 92 bool getOutputIsFixed() const { return mOutputFixed; } 93 float getFixedOutputLevel() const { return mFixedLvl; } 94 95 int getHardwareTimestamp(unsigned int *pAvail, 96 struct timespec *pTimestamp); 97 uint32_t getKernelBufferSize() { return mFramesPerChunk * mBufferChunks; } 98 99 virtual void dump(String8& result) = 0; 100 101 virtual const char* getOutputName() = 0; 102 virtual uint32_t devMask() const = 0; 103 104 virtual void cleanupResources(); 105 106 static const uint32_t kMaxDelayCompensationMSec; 107 static const uint32_t kPrimeTimeoutChunks; 108 109 protected: 110 111 void pushSilence(uint32_t nFrames); 112 // Take nBytes of chunkData, convert to output format and write at 113 // sbuf. sbuf WILL point to enough space to convert from 16 to 32 bit 114 // if needed. 115 virtual void stageChunk(const uint8_t* chunkData, 116 uint8_t* sbuf, 117 uint32_t inBytesPerSample, 118 uint32_t nSamples); 119 virtual void openPCMDevice(); 120 virtual void reset(); 121 virtual status_t getDMAStartData(int64_t* dma_start_time, 122 int64_t* frames_queued_to_driver); 123 void doPCMWrite(const uint8_t* data, size_t len); 124 void setupInternal(); 125 126 // Current state machine state. 127 State mState; 128 129 // Output format 130 uint32_t mFramesPerChunk; 131 uint32_t mFramesPerSec; 132 uint32_t mBufferChunks; 133 uint32_t mChannelCnt; 134 const char* mALSAName; 135 enum pcm_format mALSAFormat; 136 137 // These numbers are relative to the ALSA output. 138 uint32_t mBytesPerSample; 139 uint32_t mBytesPerFrame; 140 uint32_t mBytesPerChunk; 141 uint8_t* mStagingBuf; 142 143 // Get next write time stuff. 144 bool mLastNextWriteTimeValid; 145 int64_t mLastNextWriteTime; 146 int64_t mLastDMAStartTime; 147 148 // External delay compensation. 149 uint32_t mMaxDelayCompFrames; 150 uint32_t mExternalDelayUSec; 151 uint32_t mExternalDelayLocalTicks; 152 153 LinearTransform mFramesToLocalTime; 154 155 // ALSA device stuff. 156 Mutex mDeviceLock; 157 struct pcm* mDevice; 158 int mDeviceExtFd; 159 int mALSACardID; 160 uint64_t mFramesQueuedToDriver; 161 uint32_t mPrimeTimeoutChunks; 162 163 // Volume stuff 164 Mutex mVolumeLock; 165 float mVolume; 166 float mFixedLvl; 167 bool mMute; 168 bool mOutputFixed; 169 bool mVolParamsDirty; 170 virtual void applyPendingVolParams() = 0; 171 }; 172 173 typedef Vector< sp<AudioOutput> > AudioOutputList; 174 175 } // namespace android 176 #endif // ANDROID_AUDIO_OUTPUT_H 177
