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      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 
     25 namespace android {
     26 
     27 // ----------------------------------------------------------------------------
     28 
     29 #define THREAD_PRIORITY_AUDIO_CLIENT (ANDROID_PRIORITY_AUDIO)
     30 // Maximum cumulated timeout milliseconds before restarting audioflinger thread
     31 #define MAX_STARTUP_TIMEOUT_MS  3000    // Longer timeout period at startup to cope with A2DP init time
     32 #define MAX_RUN_TIMEOUT_MS      1000
     33 #define WAIT_PERIOD_MS          10
     34 
     35 
     36 struct audio_track_cblk_t
     37 {
     38 
     39     // The data members are grouped so that members accessed frequently and in the same context
     40     // are in the same line of data cache.
     41                 Mutex       lock;
     42                 Condition   cv;
     43     volatile    uint32_t    user;
     44     volatile    uint32_t    server;
     45                 uint32_t    userBase;
     46                 uint32_t    serverBase;
     47     void*       buffers;
     48     uint32_t    frameCount;
     49     // Cache line boundary
     50     uint32_t    loopStart;
     51     uint32_t    loopEnd;
     52     int         loopCount;
     53     volatile    union {
     54                     uint16_t    volume[2];
     55                     uint32_t    volumeLR;
     56                 };
     57                 uint32_t    sampleRate;
     58                 // NOTE: audio_track_cblk_t::frameSize is not equal to AudioTrack::frameSize() for
     59                 // 8 bit PCM data: in this case,  mCblk->frameSize is based on a sample size of
     60                 // 16 bit because data is converted to 16 bit before being stored in buffer
     61                 uint32_t    frameSize;
     62                 uint8_t     channels;
     63                 uint8_t     flowControlFlag; // underrun (out) or overrrun (in) indication
     64                 uint8_t     out;        // out equals 1 for AudioTrack and 0 for AudioRecord
     65                 uint8_t     forceReady;
     66                 uint16_t    bufferTimeoutMs; // Maximum cumulated timeout before restarting audioflinger
     67                 uint16_t    waitTimeMs;      // Cumulated wait time
     68                 // Cache line boundary (32 bytes)
     69 
     70                             audio_track_cblk_t();
     71                 uint32_t    stepUser(uint32_t frameCount);
     72                 bool        stepServer(uint32_t frameCount);
     73                 void*       buffer(uint32_t offset) const;
     74                 uint32_t    framesAvailable();
     75                 uint32_t    framesAvailable_l();
     76                 uint32_t    framesReady();
     77 };
     78 
     79 
     80 // ----------------------------------------------------------------------------
     81 
     82 }; // namespace android
     83 
     84 #endif // ANDROID_AUDIO_TRACK_SHARED_H
     85