AudioTrackShared.h revision b603744e96b07b1d5bf745bde593fb2c025cefcf
1/* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17#ifndef ANDROID_AUDIO_TRACK_SHARED_H 18#define ANDROID_AUDIO_TRACK_SHARED_H 19 20#include <stdint.h> 21#include <sys/types.h> 22 23#include <utils/threads.h> 24 25namespace android { 26 27// ---------------------------------------------------------------------------- 28 29// Maximum cumulated timeout milliseconds before restarting audioflinger thread 30#define MAX_STARTUP_TIMEOUT_MS 3000 // Longer timeout period at startup to cope with A2DP 31 // init time 32#define MAX_RUN_TIMEOUT_MS 1000 33#define WAIT_PERIOD_MS 10 34 35#define CBLK_UNDERRUN 0x01 // set: underrun (out) or overrrun (in), clear: no underrun or overrun 36#define CBLK_FORCEREADY 0x02 // set: track is considered ready immediately by AudioFlinger, 37 // clear: track is ready when buffer full 38#define CBLK_INVALID 0x04 // track buffer invalidated by AudioFlinger, need to re-create 39#define CBLK_DISABLED 0x08 // track disabled by AudioFlinger due to underrun, need to re-start 40 41// Important: do not add any virtual methods, including ~ 42struct audio_track_cblk_t 43{ 44 45 // The data members are grouped so that members accessed frequently and in the same context 46 // are in the same line of data cache. 47 Mutex lock; // sizeof(int) 48 Condition cv; // sizeof(int) 49 50 // next 4 are offsets within "buffers" 51 volatile uint32_t user; 52 volatile uint32_t server; 53 uint32_t userBase; 54 uint32_t serverBase; 55 56 int mPad1; // unused, but preserves cache line alignment 57 58 size_t frameCount_; // used during creation to pass actual track buffer size 59 // from AudioFlinger to client, and not referenced again 60 // FIXME remove here and replace by createTrack() in/out parameter 61 // renamed to "_" to detect incorrect use 62 63 // Cache line boundary (32 bytes) 64 65 uint32_t loopStart; 66 uint32_t loopEnd; // read-only for server, read/write for client 67 int loopCount; // read/write for client 68 69 // Channel volumes are fixed point U4.12, so 0x1000 means 1.0. 70 // Left channel is in [0:15], right channel is in [16:31]. 71 // Always read and write the combined pair atomically. 72 // For AudioTrack only, not used by AudioRecord. 73private: 74 uint32_t mVolumeLR; 75public: 76 77 uint32_t sampleRate; 78 79 uint8_t mPad2; // unused 80 81 // read-only for client, server writes once at initialization and is then read-only 82 uint8_t mName; // normal tracks: track name, fast tracks: track index 83 84 // used by client only 85 uint16_t bufferTimeoutMs; // Maximum cumulated timeout before restarting 86 // audioflinger 87 88 uint16_t waitTimeMs; // Cumulated wait time, used by client only 89private: 90 // client write-only, server read-only 91 uint16_t mSendLevel; // Fixed point U4.12 so 0x1000 means 1.0 92public: 93 volatile int32_t flags; 94 95 // Cache line boundary (32 bytes) 96 97 // Since the control block is always located in shared memory, this constructor 98 // is only used for placement new(). It is never used for regular new() or stack. 99 audio_track_cblk_t(); 100 101 // called by client only, where client includes regular 102 // AudioTrack and AudioFlinger::PlaybackThread::OutputTrack 103 uint32_t stepUserIn(size_t stepCount, size_t frameCount) { return stepUser(stepCount, frameCount, false); } 104 uint32_t stepUserOut(size_t stepCount, size_t frameCount) { return stepUser(stepCount, frameCount, true); } 105 106 bool stepServer(size_t stepCount, size_t frameCount, bool isOut); 107 108 // if there is a shared buffer, "buffers" is the value of pointer() for the shared 109 // buffer, otherwise "buffers" points immediately after the control block 110 void* buffer(void *buffers, uint32_t frameSize, uint32_t offset) const; 111 112 uint32_t framesAvailableIn(size_t frameCount) 113 { return framesAvailable(frameCount, false); } 114 uint32_t framesAvailableOut(size_t frameCount) 115 { return framesAvailable(frameCount, true); } 116 uint32_t framesAvailableIn_l(size_t frameCount) 117 { return framesAvailable_l(frameCount, false); } 118 uint32_t framesAvailableOut_l(size_t frameCount) 119 { return framesAvailable_l(frameCount, true); } 120 uint32_t framesReadyIn() { return framesReady(false); } 121 uint32_t framesReadyOut() { return framesReady(true); } 122 123 bool tryLock(); 124 125 // No barriers on the following operations, so the ordering of loads/stores 126 // with respect to other parameters is UNPREDICTABLE. That's considered safe. 127 128 // for AudioTrack client only, caller must limit to 0.0 <= sendLevel <= 1.0 129 void setSendLevel(float sendLevel) { 130 mSendLevel = uint16_t(sendLevel * 0x1000); 131 } 132 133 // for AudioFlinger only; the return value must be validated by the caller 134 uint16_t getSendLevel_U4_12() const { 135 return mSendLevel; 136 } 137 138 // for AudioTrack client only, caller must limit to 0 <= volumeLR <= 0x10001000 139 void setVolumeLR(uint32_t volumeLR) { 140 mVolumeLR = volumeLR; 141 } 142 143 // for AudioFlinger only; the return value must be validated by the caller 144 uint32_t getVolumeLR() const { 145 return mVolumeLR; 146 } 147 148private: 149 // isOut == true means AudioTrack, isOut == false means AudioRecord 150 uint32_t stepUser(size_t stepCount, size_t frameCount, bool isOut); 151 uint32_t framesAvailable(size_t frameCount, bool isOut); 152 uint32_t framesAvailable_l(size_t frameCount, bool isOut); 153 uint32_t framesReady(bool isOut); 154}; 155 156 157// ---------------------------------------------------------------------------- 158 159}; // namespace android 160 161#endif // ANDROID_AUDIO_TRACK_SHARED_H 162