1/*
2 * Copyright (C) 2016 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_HARDWARE_STREAM_HAL_INTERFACE_H
18#define ANDROID_HARDWARE_STREAM_HAL_INTERFACE_H
19
20#include <media/audiohal/EffectHalInterface.h>
21#include <system/audio.h>
22#include <utils/Errors.h>
23#include <utils/RefBase.h>
24#include <utils/String8.h>
25
26namespace android {
27
28class StreamHalInterface : public virtual RefBase
29{
30  public:
31    // Return the sampling rate in Hz - eg. 44100.
32    virtual status_t getSampleRate(uint32_t *rate) = 0;
33
34    // Return size of input/output buffer in bytes for this stream - eg. 4800.
35    virtual status_t getBufferSize(size_t *size) = 0;
36
37    // Return the channel mask.
38    virtual status_t getChannelMask(audio_channel_mask_t *mask) = 0;
39
40    // Return the audio format - e.g. AUDIO_FORMAT_PCM_16_BIT.
41    virtual status_t getFormat(audio_format_t *format) = 0;
42
43    // Convenience method.
44    virtual status_t getAudioProperties(
45            uint32_t *sampleRate, audio_channel_mask_t *mask, audio_format_t *format) = 0;
46
47    // Set audio stream parameters.
48    virtual status_t setParameters(const String8& kvPairs) = 0;
49
50    // Get audio stream parameters.
51    virtual status_t getParameters(const String8& keys, String8 *values) = 0;
52
53    // Return the frame size (number of bytes per sample) of a stream.
54    virtual status_t getFrameSize(size_t *size) = 0;
55
56    // Add or remove the effect on the stream.
57    virtual status_t addEffect(sp<EffectHalInterface> effect) = 0;
58    virtual status_t removeEffect(sp<EffectHalInterface> effect) = 0;
59
60    // Put the audio hardware input/output into standby mode.
61    virtual status_t standby() = 0;
62
63    virtual status_t dump(int fd) = 0;
64
65    // Start a stream operating in mmap mode.
66    virtual status_t start() = 0;
67
68    // Stop a stream operating in mmap mode.
69    virtual status_t stop() = 0;
70
71    // Retrieve information on the data buffer in mmap mode.
72    virtual status_t createMmapBuffer(int32_t minSizeFrames,
73                                      struct audio_mmap_buffer_info *info) = 0;
74
75    // Get current read/write position in the mmap buffer
76    virtual status_t getMmapPosition(struct audio_mmap_position *position) = 0;
77
78    // Set the priority of the thread that interacts with the HAL
79    // (must match the priority of the audioflinger's thread that calls 'read' / 'write')
80    virtual status_t setHalThreadPriority(int priority) = 0;
81
82  protected:
83    // Subclasses can not be constructed directly by clients.
84    StreamHalInterface() {}
85
86    // The destructor automatically closes the stream.
87    virtual ~StreamHalInterface() {}
88};
89
90class StreamOutHalInterfaceCallback : public virtual RefBase {
91  public:
92    virtual void onWriteReady() {}
93    virtual void onDrainReady() {}
94    virtual void onError() {}
95
96  protected:
97    StreamOutHalInterfaceCallback() {}
98    virtual ~StreamOutHalInterfaceCallback() {}
99};
100
101class StreamOutHalInterface : public virtual StreamHalInterface {
102  public:
103    // Return the audio hardware driver estimated latency in milliseconds.
104    virtual status_t getLatency(uint32_t *latency) = 0;
105
106    // Use this method in situations where audio mixing is done in the hardware.
107    virtual status_t setVolume(float left, float right) = 0;
108
109    // Write audio buffer to driver.
110    virtual status_t write(const void *buffer, size_t bytes, size_t *written) = 0;
111
112    // Return the number of audio frames written by the audio dsp to DAC since
113    // the output has exited standby.
114    virtual status_t getRenderPosition(uint32_t *dspFrames) = 0;
115
116    // Get the local time at which the next write to the audio driver will be presented.
117    virtual status_t getNextWriteTimestamp(int64_t *timestamp) = 0;
118
119    // Set the callback for notifying completion of non-blocking write and drain.
120    // The callback must be owned by someone else. The output stream does not own it
121    // to avoid strong pointer loops.
122    virtual status_t setCallback(wp<StreamOutHalInterfaceCallback> callback) = 0;
123
124    // Returns whether pause and resume operations are supported.
125    virtual status_t supportsPauseAndResume(bool *supportsPause, bool *supportsResume) = 0;
126
127    // Notifies to the audio driver to resume playback following a pause.
128    virtual status_t pause() = 0;
129
130    // Notifies to the audio driver to resume playback following a pause.
131    virtual status_t resume() = 0;
132
133    // Returns whether drain operation is supported.
134    virtual status_t supportsDrain(bool *supportsDrain) = 0;
135
136    // Requests notification when data buffered by the driver/hardware has been played.
137    virtual status_t drain(bool earlyNotify) = 0;
138
139    // Notifies to the audio driver to flush the queued data.
140    virtual status_t flush() = 0;
141
142    // Return a recent count of the number of audio frames presented to an external observer.
143    virtual status_t getPresentationPosition(uint64_t *frames, struct timespec *timestamp) = 0;
144
145  protected:
146    virtual ~StreamOutHalInterface() {}
147};
148
149class StreamInHalInterface : public virtual StreamHalInterface {
150  public:
151    // Set the input gain for the audio driver.
152    virtual status_t setGain(float gain) = 0;
153
154    // Read audio buffer in from driver.
155    virtual status_t read(void *buffer, size_t bytes, size_t *read) = 0;
156
157    // Return the amount of input frames lost in the audio driver.
158    virtual status_t getInputFramesLost(uint32_t *framesLost) = 0;
159
160    // Return a recent count of the number of audio frames received and
161    // the clock time associated with that frame count.
162    virtual status_t getCapturePosition(int64_t *frames, int64_t *time) = 0;
163
164  protected:
165    virtual ~StreamInHalInterface() {}
166};
167
168} // namespace android
169
170#endif // ANDROID_HARDWARE_STREAM_HAL_INTERFACE_H
171