FastMixerState.h revision c56f3426099a3cf2d07ccff8886050c7fbce140f 
1/*
2 * Copyright (C) 2012 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_FAST_MIXER_STATE_H
18#define ANDROID_AUDIO_FAST_MIXER_STATE_H
19
20#include <audio_utils/minifloat.h>
21#include <system/audio.h>
22#include <media/ExtendedAudioBufferProvider.h>
23#include <media/nbaio/NBAIO.h>
24#include <media/nbaio/NBLog.h>
25#include "FastThreadState.h"
26
27namespace android {
28
29struct FastMixerDumpState;
30
31class VolumeProvider {
32public:
33    // The provider implementation is responsible for validating that the return value is in range.
34    virtual gain_minifloat_packed_t getVolumeLR() = 0;
35protected:
36    VolumeProvider() { }
37    virtual ~VolumeProvider() { }
38};
39
40// Represents the state of a fast track
41struct FastTrack {
42    FastTrack();
43    /*virtual*/ ~FastTrack();
44
45    ExtendedAudioBufferProvider* mBufferProvider; // must be NULL if inactive, or non-NULL if active
46    VolumeProvider*         mVolumeProvider; // optional; if NULL then full-scale
47    audio_channel_mask_t    mChannelMask;    // AUDIO_CHANNEL_OUT_MONO or AUDIO_CHANNEL_OUT_STEREO
48    int                     mGeneration;     // increment when any field is assigned
49};
50
51// Represents a single state of the fast mixer
52struct FastMixerState : FastThreadState {
53                FastMixerState();
54    /*virtual*/ ~FastMixerState();
55
56    static const unsigned kMaxFastTracks = 8;   // must be between 2 and 32 inclusive
57
58    // all pointer fields use raw pointers; objects are owned and ref-counted by the normal mixer
59    FastTrack   mFastTracks[kMaxFastTracks];
60    int         mFastTracksGen; // increment when any mFastTracks[i].mGeneration is incremented
61    unsigned    mTrackMask;     // bit i is set if and only if mFastTracks[i] is active
62    NBAIO_Sink* mOutputSink;    // HAL output device, must already be negotiated
63    int         mOutputSinkGen; // increment when mOutputSink is assigned
64    size_t      mFrameCount;    // number of frames per fast mix buffer
65
66    // Extends FastThreadState::Command
67    static const Command
68        // The following commands also process configuration changes, and can be "or"ed:
69        MIX = 0x8,              // mix tracks
70        WRITE = 0x10,           // write to output sink
71        MIX_WRITE = 0x18;       // mix tracks and write to output sink
72
73    // This might be a one-time configuration rather than per-state
74    NBAIO_Sink* mTeeSink;       // if non-NULL, then duplicate write()s to this non-blocking sink
75};  // struct FastMixerState
76
77}   // namespace android
78
79#endif  // ANDROID_AUDIO_FAST_MIXER_STATE_H
80