AudioSystem.h revision ad3af3305f024bcbbd55c894a4995e449498e1ba 
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(audio_io_handle_t output,
132                                      size_t *halFrames,
133                                      size_t *dspFrames,
134                                      audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
135
136    // return the number of input frames lost by HAL implementation, or 0 if the handle is invalid
137    static size_t getInputFramesLost(audio_io_handle_t ioHandle);
138
139    static int newAudioSessionId();
140    static void acquireAudioSessionId(int audioSession);
141    static void releaseAudioSessionId(int audioSession);
142
143    // types of io configuration change events received with ioConfigChanged()
144    enum io_config_event {
145        OUTPUT_OPENED,
146        OUTPUT_CLOSED,
147        OUTPUT_CONFIG_CHANGED,
148        INPUT_OPENED,
149        INPUT_CLOSED,
150        INPUT_CONFIG_CHANGED,
151        STREAM_CONFIG_CHANGED,
152        NUM_CONFIG_EVENTS
153    };
154
155    // audio output descriptor used to cache output configurations in client process to avoid
156    // frequent calls through IAudioFlinger
157    class OutputDescriptor {
158    public:
159        OutputDescriptor()
160        : samplingRate(0), format(AUDIO_FORMAT_DEFAULT), channels(0), frameCount(0), latency(0)  {}
161
162        uint32_t samplingRate;
163        int32_t format;
164        int32_t channels;
165        size_t frameCount;
166        uint32_t latency;
167    };
168
169    // Events used to synchronize actions between audio sessions.
170    // For instance SYNC_EVENT_PRESENTATION_COMPLETE can be used to delay recording start until
171    // playback is complete on another audio session.
172    // See definitions in MediaSyncEvent.java
173    enum sync_event_t {
174        SYNC_EVENT_SAME = -1,             // used internally to indicate restart with same event
175        SYNC_EVENT_NONE = 0,
176        SYNC_EVENT_PRESENTATION_COMPLETE,
177
178        //
179        // Define new events here: SYNC_EVENT_START, SYNC_EVENT_STOP, SYNC_EVENT_TIME ...
180        //
181        SYNC_EVENT_CNT,
182    };
183
184    // Timeout for synchronous record start. Prevents from blocking the record thread forever
185    // if the trigger event is not fired.
186    static const uint32_t kSyncRecordStartTimeOutMs = 30000;
187
188    //
189    // IAudioPolicyService interface (see AudioPolicyInterface for method descriptions)
190    //
191    static status_t setDeviceConnectionState(audio_devices_t device, audio_policy_dev_state_t state,
192                                                const char *device_address);
193    static audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device,
194                                                                const char *device_address);
195    static status_t setPhoneState(audio_mode_t state);
196    static status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
197    static audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
198    static audio_io_handle_t getOutput(audio_stream_type_t stream,
199                                        uint32_t samplingRate = 0,
200                                        audio_format_t format = AUDIO_FORMAT_DEFAULT,
201                                        audio_channel_mask_t channelMask = AUDIO_CHANNEL_OUT_STEREO,
202                                        audio_output_flags_t flags = AUDIO_OUTPUT_FLAG_NONE,
203                                        const audio_offload_info_t *offloadInfo = NULL);
204    static status_t startOutput(audio_io_handle_t output,
205                                audio_stream_type_t stream,
206                                int session = 0);
207    static status_t stopOutput(audio_io_handle_t output,
208                               audio_stream_type_t stream,
209                               int session = 0);
210    static void releaseOutput(audio_io_handle_t output);
211    static audio_io_handle_t getInput(audio_source_t inputSource,
212                                    uint32_t samplingRate = 0,
213                                    audio_format_t format = AUDIO_FORMAT_DEFAULT,
214                                    audio_channel_mask_t channelMask = AUDIO_CHANNEL_IN_MONO,
215                                    int sessionId = 0);
216    static status_t startInput(audio_io_handle_t input);
217    static status_t stopInput(audio_io_handle_t input);
218    static void releaseInput(audio_io_handle_t input);
219    static status_t initStreamVolume(audio_stream_type_t stream,
220                                      int indexMin,
221                                      int indexMax);
222    static status_t setStreamVolumeIndex(audio_stream_type_t stream,
223                                         int index,
224                                         audio_devices_t device);
225    static status_t getStreamVolumeIndex(audio_stream_type_t stream,
226                                         int *index,
227                                         audio_devices_t device);
228
229    static uint32_t getStrategyForStream(audio_stream_type_t stream);
230    static audio_devices_t getDevicesForStream(audio_stream_type_t stream);
231
232    static audio_io_handle_t getOutputForEffect(const effect_descriptor_t *desc);
233    static status_t registerEffect(const effect_descriptor_t *desc,
234                                    audio_io_handle_t io,
235                                    uint32_t strategy,
236                                    int session,
237                                    int id);
238    static status_t unregisterEffect(int id);
239    static status_t setEffectEnabled(int id, bool enabled);
240
241    // clear stream to output mapping cache (gStreamOutputMap)
242    // and output configuration cache (gOutputs)
243    static void clearAudioConfigCache();
244
245    static const sp<IAudioPolicyService>& get_audio_policy_service();
246
247    // helpers for android.media.AudioManager.getProperty(), see description there for meaning
248    static uint32_t getPrimaryOutputSamplingRate();
249    static size_t getPrimaryOutputFrameCount();
250
251    // Check if hw offload is possible for given format, stream type, sample rate,
252    // bit rate, duration, video and streaming or offload property is enabled
253    static bool isOffloadSupported(const audio_offload_info_t& info);
254
255    // ----------------------------------------------------------------------------
256
257private:
258
259    class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
260    {
261    public:
262        AudioFlingerClient() {
263        }
264
265        // DeathRecipient
266        virtual void binderDied(const wp<IBinder>& who);
267
268        // IAudioFlingerClient
269
270        // indicate a change in the configuration of an output or input: keeps the cached
271        // values for output/input parameters up-to-date in client process
272        virtual void ioConfigChanged(int event, audio_io_handle_t ioHandle, const void *param2);
273    };
274
275    class AudioPolicyServiceClient: public IBinder::DeathRecipient
276    {
277    public:
278        AudioPolicyServiceClient() {
279        }
280
281        // DeathRecipient
282        virtual void binderDied(const wp<IBinder>& who);
283    };
284
285    static sp<AudioFlingerClient> gAudioFlingerClient;
286    static sp<AudioPolicyServiceClient> gAudioPolicyServiceClient;
287    friend class AudioFlingerClient;
288    friend class AudioPolicyServiceClient;
289
290    static Mutex gLock;
291    static sp<IAudioFlinger> gAudioFlinger;
292    static audio_error_callback gAudioErrorCallback;
293
294    static size_t gInBuffSize;
295    // previous parameters for recording buffer size queries
296    static uint32_t gPrevInSamplingRate;
297    static audio_format_t gPrevInFormat;
298    static audio_channel_mask_t gPrevInChannelMask;
299
300    static sp<IAudioPolicyService> gAudioPolicyService;
301
302    // mapping between stream types and outputs
303    static DefaultKeyedVector<audio_stream_type_t, audio_io_handle_t> gStreamOutputMap;
304    // list of output descriptors containing cached parameters
305    // (sampling rate, framecount, channel count...)
306    static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
307};
308
309};  // namespace android
310
311#endif  /*ANDROID_AUDIOSYSTEM_H_*/
312