AudioTrackShared.h revision be916aa1267e2e6b1c148f51d11bcbbc79cb864c 
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#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#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: must be re-created
46#define CBLK_INVALID_OFF        0x0000
47
48struct audio_track_cblk_t
49{
50
51    // The data members are grouped so that members accessed frequently and in the same context
52    // are in the same line of data cache.
53                Mutex       lock;
54                Condition   cv;
55    volatile    uint32_t    user;
56    volatile    uint32_t    server;
57                uint32_t    userBase;
58                uint32_t    serverBase;
59                void*       buffers;
60                uint32_t    frameCount;
61                // Cache line boundary
62                uint32_t    loopStart;
63                uint32_t    loopEnd;
64                int         loopCount;
65    volatile    union {
66                    uint16_t    volume[2];
67                    uint32_t    volumeLR;
68                };
69                uint32_t    sampleRate;
70                // NOTE: audio_track_cblk_t::frameSize is not equal to AudioTrack::frameSize() for
71                // 8 bit PCM data: in this case,  mCblk->frameSize is based on a sample size of
72                // 16 bit because data is converted to 16 bit before being stored in buffer
73
74                uint8_t     frameSize;
75                uint8_t     channelCount;
76                uint16_t    flags;
77
78                uint16_t    bufferTimeoutMs; // Maximum cumulated timeout before restarting audioflinger
79                uint16_t    waitTimeMs;      // Cumulated wait time
80
81                uint16_t    sendLevel;
82                uint16_t    reserved;
83                // Cache line boundary (32 bytes)
84                            audio_track_cblk_t();
85                uint32_t    stepUser(uint32_t frameCount);
86                bool        stepServer(uint32_t frameCount);
87                void*       buffer(uint32_t offset) const;
88                uint32_t    framesAvailable();
89                uint32_t    framesAvailable_l();
90                uint32_t    framesReady();
91};
92
93
94// ----------------------------------------------------------------------------
95
96}; // namespace android
97
98#endif // ANDROID_AUDIO_TRACK_SHARED_H
99