AudioTrackShared.h revision 99e53b86eebb605b70dd7591b89bf61a9414ed0e
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 init time 31#define MAX_RUN_TIMEOUT_MS 1000 32#define WAIT_PERIOD_MS 10 33#define RESTORE_TIMEOUT_MS 5000 // Maximum waiting time for a track to be restored 34 35#define CBLK_UNDERRUN_MSK 0x0001 36#define CBLK_UNDERRUN_ON 0x0001 // underrun (out) or overrrun (in) indication 37#define CBLK_UNDERRUN_OFF 0x0000 // no underrun 38#define CBLK_DIRECTION_MSK 0x0002 39#define CBLK_DIRECTION_OUT 0x0002 // this cblk is for an AudioTrack 40#define CBLK_DIRECTION_IN 0x0000 // this cblk is for an AudioRecord 41#define CBLK_FORCEREADY_MSK 0x0004 42#define CBLK_FORCEREADY_ON 0x0004 // track is considered ready immediately by AudioFlinger 43#define CBLK_FORCEREADY_OFF 0x0000 // track is ready when buffer full 44#define CBLK_INVALID_MSK 0x0008 45#define CBLK_INVALID_ON 0x0008 // track buffer is invalidated by AudioFlinger: 46#define CBLK_INVALID_OFF 0x0000 // must be re-created 47#define CBLK_DISABLED_MSK 0x0010 48#define CBLK_DISABLED_ON 0x0010 // track disabled by AudioFlinger due to underrun: 49#define CBLK_DISABLED_OFF 0x0000 // must be re-started 50#define CBLK_RESTORING_MSK 0x0020 51#define CBLK_RESTORING_ON 0x0020 // track is being restored after invalidation 52#define CBLK_RESTORING_OFF 0x0000 // by AudioFlinger 53#define CBLK_RESTORED_MSK 0x0040 54#define CBLK_RESTORED_ON 0x0040 // track has been restored after invalidation 55#define CBLK_RESTORED_OFF 0x0040 // by AudioFlinger 56 57// Important: do not add any virtual methods, including ~ 58struct audio_track_cblk_t 59{ 60 61 // The data members are grouped so that members accessed frequently and in the same context 62 // are in the same line of data cache. 63 Mutex lock; // sizeof(int) 64 Condition cv; // sizeof(int) 65 66 // next 4 are offsets within "buffers" 67 volatile uint32_t user; 68 volatile uint32_t server; 69 uint32_t userBase; 70 uint32_t serverBase; 71 72 // if there is a shared buffer, "buffers" is the value of pointer() for the shared 73 // buffer, otherwise "buffers" points immediately after the control block 74 void* buffers; 75 uint32_t frameCount; 76 77 // Cache line boundary 78 79 uint32_t loopStart; 80 uint32_t loopEnd; // read-only for server, read/write for client 81 int loopCount; // read/write for client 82 83 // Channel volumes are fixed point U4.12, so 0x1000 means 1.0. 84 // Left channel is in [0:15], right channel is in [16:31]. 85 // Always read and write the combined pair atomically. 86 // For AudioTrack only, not used by AudioRecord. 87private: 88 uint32_t mVolumeLR; 89public: 90 91 uint32_t sampleRate; 92 93 // NOTE: audio_track_cblk_t::frameSize is not equal to AudioTrack::frameSize() for 94 // 8 bit PCM data: in this case, mCblk->frameSize is based on a sample size of 95 // 16 bit because data is converted to 16 bit before being stored in buffer 96 97 // read-only for client, server writes once at initialization and is then read-only 98 uint8_t frameSize; // would normally be size_t, but 8 bits is plenty 99 100 // never used 101 uint8_t pad1; 102 103 // used by client only 104 uint16_t bufferTimeoutMs; // Maximum cumulated timeout before restarting audioflinger 105 106 uint16_t waitTimeMs; // Cumulated wait time, used by client only 107private: 108 // client write-only, server read-only 109 uint16_t mSendLevel; // Fixed point U4.12 so 0x1000 means 1.0 110public: 111 volatile int32_t flags; 112 113 // Cache line boundary (32 bytes) 114 115 // Since the control block is always located in shared memory, this constructor 116 // is only used for placement new(). It is never used for regular new() or stack. 117 audio_track_cblk_t(); 118 uint32_t stepUser(uint32_t frameCount); // called by client only, where 119 // client includes regular AudioTrack and AudioFlinger::PlaybackThread::OutputTrack 120 bool stepServer(uint32_t frameCount); // called by server only 121 void* buffer(uint32_t offset) const; 122 uint32_t framesAvailable(); 123 uint32_t framesAvailable_l(); 124 uint32_t framesReady(); // called by server only 125 bool tryLock(); 126 127 // No barriers on the following operations, so the ordering of loads/stores 128 // with respect to other parameters is UNPREDICTABLE. That's considered safe. 129 130 // for AudioTrack client only, caller must limit to 0.0 <= sendLevel <= 1.0 131 void setSendLevel(float sendLevel) { 132 mSendLevel = uint16_t(sendLevel * 0x1000); 133 } 134 135 // for AudioFlinger only; the return value must be validated by the caller 136 uint16_t getSendLevel_U4_12() const { 137 return mSendLevel; 138 } 139 140 // for AudioTrack client only, caller must limit to 0 <= volumeLR <= 0x10001000 141 void setVolumeLR(uint32_t volumeLR) { 142 mVolumeLR = volumeLR; 143 } 144 145 // for AudioFlinger only; the return value must be validated by the caller 146 uint32_t getVolumeLR() const { 147 return mVolumeLR; 148 } 149 150}; 151 152 153// ---------------------------------------------------------------------------- 154 155}; // namespace android 156 157#endif // ANDROID_AUDIO_TRACK_SHARED_H 158