AudioSystem.h revision e336f9113bdd35119866a3c3f8008ca01c576660 
1/*
2 * Copyright (C) 2008 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_AUDIOSYSTEM_H_
18#define ANDROID_AUDIOSYSTEM_H_
19
20#include <utils/RefBase.h>
21#include <utils/threads.h>
22#include <media/IAudioFlinger.h>
23
24#include <system/audio.h>
25#include <system/audio_policy.h>
26
27/* XXX: Should be include by all the users instead */
28#include <media/AudioParameter.h>
29
30namespace android {
31
32typedef void (*audio_error_callback)(status_t err);
33
34class IAudioPolicyService;
35class String8;
36
37class AudioSystem
38{
39public:
40
41    /* These are static methods to control the system-wide AudioFlinger
42     * only privileged processes can have access to them
43     */
44
45    // mute/unmute microphone
46    static status_t muteMicrophone(bool state);
47    static status_t isMicrophoneMuted(bool *state);
48
49    // set/get master volume
50    static status_t setMasterVolume(float value);
51    static status_t getMasterVolume(float* volume);
52
53    // mute/unmute audio outputs
54    static status_t setMasterMute(bool mute);
55    static status_t getMasterMute(bool* mute);
56
57    // set/get stream volume on specified output
58    static status_t setStreamVolume(audio_stream_type_t stream, float value,
59                                    audio_io_handle_t output);
60    static status_t getStreamVolume(audio_stream_type_t stream, float* volume,
61                                    audio_io_handle_t output);
62
63    // mute/unmute stream
64    static status_t setStreamMute(audio_stream_type_t stream, bool mute);
65    static status_t getStreamMute(audio_stream_type_t stream, bool* mute);
66
67    // set audio mode in audio hardware
68    static status_t setMode(audio_mode_t mode);
69
70    // returns true in *state if tracks are active on the specified stream or have been active
71    // in the past inPastMs milliseconds
72    static status_t isStreamActive(audio_stream_type_t stream, bool *state, uint32_t inPastMs = 0);
73    // returns true in *state if tracks are active for what qualifies as remote playback
74    // on the specified stream or have been active in the past inPastMs milliseconds. Remote
75    // playback isn't mutually exclusive with local playback.
76    static status_t isStreamActiveRemotely(audio_stream_type_t stream, bool *state,
77            uint32_t inPastMs = 0);
78    // returns true in *state if a recorder is currently recording with the specified source
79    static status_t isSourceActive(audio_source_t source, bool *state);
80
81    // set/get audio hardware parameters. The function accepts a list of parameters
82    // key value pairs in the form: key1=value1;key2=value2;...
83    // Some keys are reserved for standard parameters (See AudioParameter class).
84    static status_t setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs);
85    static String8  getParameters(audio_io_handle_t ioHandle, const String8& keys);
86
87    static void setErrorCallback(audio_error_callback cb);
88
89    // helper function to obtain AudioFlinger service handle
90    static const sp<IAudioFlinger>& get_audio_flinger();
91
92    static float linearToLog(int volume);
93    static int logToLinear(float volume);
94
95    static status_t getOutputSamplingRate(uint32_t* samplingRate,
96            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
97    static status_t getOutputFrameCount(size_t* frameCount,
98            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
99    static status_t getOutputLatency(uint32_t* latency,
100            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
101    static status_t getSamplingRate(audio_io_handle_t output,
102                                          audio_stream_type_t streamType,
103                                          uint32_t* samplingRate);
104    // returns the number of frames per audio HAL write buffer. Corresponds to
105    // audio_stream->get_buffer_size()/audio_stream_frame_size()
106    static status_t getFrameCount(audio_io_handle_t output,
107                                  audio_stream_type_t stream,
108                                  size_t* frameCount);
109    // returns the audio output stream latency in ms. Corresponds to
110    // audio_stream_out->get_latency()
111    static status_t getLatency(audio_io_handle_t output,
112                               audio_stream_type_t stream,
113                               uint32_t* latency);
114
115    static bool routedToA2dpOutput(audio_stream_type_t streamType);
116
117    static status_t getInputBufferSize(uint32_t sampleRate, audio_format_t format,
118        audio_channel_mask_t channelMask, size_t* buffSize);
119
120    static status_t setVoiceVolume(float volume);
121
122    // return the number of audio frames written by AudioFlinger to audio HAL and
123    // audio dsp to DAC since the output on which the specified stream is playing
124    // has exited standby.
125    // returned status (from utils/Errors.h) can be:
126    // - NO_ERROR: successful operation, halFrames and dspFrames point to valid data
127    // - INVALID_OPERATION: Not supported on current hardware platform
128    // - BAD_VALUE: invalid parameter
129    // NOTE: this feature is not supported on all hardware platforms and it is
130    // necessary to check returned status before using the returned values.
131    static status_t getRenderPosition(size_t *halFrames, size_t *dspFrames,
132            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
133
134    // return the number of input frames lost by HAL implementation, or 0 if the handle is invalid
135    static size_t getInputFramesLost(audio_io_handle_t ioHandle);
136
137    static int newAudioSessionId();
138    static void acquireAudioSessionId(int audioSession);
139    static void releaseAudioSessionId(int audioSession);
140
141    // types of io configuration change events received with ioConfigChanged()
142    enum io_config_event {
143        OUTPUT_OPENED,
144        OUTPUT_CLOSED,
145        OUTPUT_CONFIG_CHANGED,
146        INPUT_OPENED,
147        INPUT_CLOSED,
148        INPUT_CONFIG_CHANGED,
149        STREAM_CONFIG_CHANGED,
150        NUM_CONFIG_EVENTS
151    };
152
153    // audio output descriptor used to cache output configurations in client process to avoid
154    // frequent calls through IAudioFlinger
155    class OutputDescriptor {
156    public:
157        OutputDescriptor()
158        : samplingRate(0), format(AUDIO_FORMAT_DEFAULT), channels(0), frameCount(0), latency(0)  {}
159
160        uint32_t samplingRate;
161        int32_t format;
162        int32_t channels;
163        size_t frameCount;
164        uint32_t latency;
165    };
166
167    // Events used to synchronize actions between audio sessions.
168    // For instance SYNC_EVENT_PRESENTATION_COMPLETE can be used to delay recording start until
169    // playback is complete on another audio session.
170    // See definitions in MediaSyncEvent.java
171    enum sync_event_t {
172        SYNC_EVENT_SAME = -1,             // used internally to indicate restart with same event
173        SYNC_EVENT_NONE = 0,
174        SYNC_EVENT_PRESENTATION_COMPLETE,
175
176        //
177        // Define new events here: SYNC_EVENT_START, SYNC_EVENT_STOP, SYNC_EVENT_TIME ...
178        //
179        SYNC_EVENT_CNT,
180    };
181
182    // Timeout for synchronous record start. Prevents from blocking the record thread forever
183    // if the trigger event is not fired.
184    static const uint32_t kSyncRecordStartTimeOutMs = 30000;
185
186    //
187    // IAudioPolicyService interface (see AudioPolicyInterface for method descriptions)
188    //
189    static status_t setDeviceConnectionState(audio_devices_t device, audio_policy_dev_state_t state,
190                                                const char *device_address);
191    static audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device,
192                                                                const char *device_address);
193    static status_t setPhoneState(audio_mode_t state);
194    static status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
195    static audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
196    static audio_io_handle_t getOutput(audio_stream_type_t stream,
197                                        uint32_t samplingRate = 0,
198                                        audio_format_t format = AUDIO_FORMAT_DEFAULT,
199                                        audio_channel_mask_t channelMask = AUDIO_CHANNEL_OUT_STEREO,
200                                        audio_output_flags_t flags = AUDIO_OUTPUT_FLAG_NONE);
201    static status_t startOutput(audio_io_handle_t output,
202                                audio_stream_type_t stream,
203                                int session = 0);
204    static status_t stopOutput(audio_io_handle_t output,
205                               audio_stream_type_t stream,
206                               int session = 0);
207    static void releaseOutput(audio_io_handle_t output);
208    static audio_io_handle_t getInput(audio_source_t inputSource,
209                                    uint32_t samplingRate = 0,
210                                    audio_format_t format = AUDIO_FORMAT_DEFAULT,
211                                    audio_channel_mask_t channelMask = AUDIO_CHANNEL_IN_MONO,
212                                    int sessionId = 0);
213    static status_t startInput(audio_io_handle_t input);
214    static status_t stopInput(audio_io_handle_t input);
215    static void releaseInput(audio_io_handle_t input);
216    static status_t initStreamVolume(audio_stream_type_t stream,
217                                      int indexMin,
218                                      int indexMax);
219    static status_t setStreamVolumeIndex(audio_stream_type_t stream,
220                                         int index,
221                                         audio_devices_t device);
222    static status_t getStreamVolumeIndex(audio_stream_type_t stream,
223                                         int *index,
224                                         audio_devices_t device);
225
226    static uint32_t getStrategyForStream(audio_stream_type_t stream);
227    static audio_devices_t getDevicesForStream(audio_stream_type_t stream);
228
229    static audio_io_handle_t getOutputForEffect(const effect_descriptor_t *desc);
230    static status_t registerEffect(const effect_descriptor_t *desc,
231                                    audio_io_handle_t io,
232                                    uint32_t strategy,
233                                    int session,
234                                    int id);
235    static status_t unregisterEffect(int id);
236    static status_t setEffectEnabled(int id, bool enabled);
237
238    // clear stream to output mapping cache (gStreamOutputMap)
239    // and output configuration cache (gOutputs)
240    static void clearAudioConfigCache();
241
242    static const sp<IAudioPolicyService>& get_audio_policy_service();
243
244    // helpers for android.media.AudioManager.getProperty(), see description there for meaning
245    static uint32_t getPrimaryOutputSamplingRate();
246    static size_t getPrimaryOutputFrameCount();
247
248    // ----------------------------------------------------------------------------
249
250private:
251
252    class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
253    {
254    public:
255        AudioFlingerClient() {
256        }
257
258        // DeathRecipient
259        virtual void binderDied(const wp<IBinder>& who);
260
261        // IAudioFlingerClient
262
263        // indicate a change in the configuration of an output or input: keeps the cached
264        // values for output/input parameters up-to-date in client process
265        virtual void ioConfigChanged(int event, audio_io_handle_t ioHandle, const void *param2);
266    };
267
268    class AudioPolicyServiceClient: public IBinder::DeathRecipient
269    {
270    public:
271        AudioPolicyServiceClient() {
272        }
273
274        // DeathRecipient
275        virtual void binderDied(const wp<IBinder>& who);
276    };
277
278    static sp<AudioFlingerClient> gAudioFlingerClient;
279    static sp<AudioPolicyServiceClient> gAudioPolicyServiceClient;
280    friend class AudioFlingerClient;
281    friend class AudioPolicyServiceClient;
282
283    static Mutex gLock;
284    static sp<IAudioFlinger> gAudioFlinger;
285    static audio_error_callback gAudioErrorCallback;
286
287    static size_t gInBuffSize;
288    // previous parameters for recording buffer size queries
289    static uint32_t gPrevInSamplingRate;
290    static audio_format_t gPrevInFormat;
291    static audio_channel_mask_t gPrevInChannelMask;
292
293    static sp<IAudioPolicyService> gAudioPolicyService;
294
295    // mapping between stream types and outputs
296    static DefaultKeyedVector<audio_stream_type_t, audio_io_handle_t> gStreamOutputMap;
297    // list of output descriptors containing cached parameters
298    // (sampling rate, framecount, channel count...)
299    static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
300};
301
302};  // namespace android
303
304#endif  /*ANDROID_AUDIOSYSTEM_H_*/
305