AudioSystem.h revision 85ab62c4b433df3f1a9826bed1c9bec07a86c750 
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 has 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 a recorder is currently recording with the specified source
74    static status_t isSourceActive(audio_source_t source, bool *state);
75
76    // set/get audio hardware parameters. The function accepts a list of parameters
77    // key value pairs in the form: key1=value1;key2=value2;...
78    // Some keys are reserved for standard parameters (See AudioParameter class).
79    static status_t setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs);
80    static String8  getParameters(audio_io_handle_t ioHandle, const String8& keys);
81
82    static void setErrorCallback(audio_error_callback cb);
83
84    // helper function to obtain AudioFlinger service handle
85    static const sp<IAudioFlinger>& get_audio_flinger();
86
87    static float linearToLog(int volume);
88    static int logToLinear(float volume);
89
90    static status_t getOutputSamplingRate(int* samplingRate,
91            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
92    static status_t getOutputFrameCount(int* frameCount,
93            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
94    static status_t getOutputLatency(uint32_t* latency,
95            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
96    static status_t getSamplingRate(audio_io_handle_t output,
97                                          audio_stream_type_t streamType,
98                                          int* samplingRate);
99    // returns the number of frames per audio HAL write buffer. Corresponds to
100    // audio_stream->get_buffer_size()/audio_stream_frame_size()
101    static status_t getFrameCount(audio_io_handle_t output,
102                                  audio_stream_type_t stream,
103                                  int* frameCount);
104    // returns the audio output stream latency in ms. Corresponds to
105    // audio_stream_out->get_latency()
106    static status_t getLatency(audio_io_handle_t output,
107                               audio_stream_type_t stream,
108                               uint32_t* latency);
109
110    // DEPRECATED
111    static status_t getOutputSamplingRate(int* samplingRate, int stream = AUDIO_STREAM_DEFAULT);
112
113    // DEPRECATED
114    static status_t getOutputFrameCount(int* frameCount, int stream = AUDIO_STREAM_DEFAULT);
115
116    static bool routedToA2dpOutput(audio_stream_type_t streamType);
117
118    static status_t getInputBufferSize(uint32_t sampleRate, audio_format_t format,
119        audio_channel_mask_t channelMask, size_t* buffSize);
120
121    static status_t setVoiceVolume(float volume);
122
123    // return the number of audio frames written by AudioFlinger to audio HAL and
124    // audio dsp to DAC since the output on which the specified stream is playing
125    // has exited standby.
126    // returned status (from utils/Errors.h) can be:
127    // - NO_ERROR: successful operation, halFrames and dspFrames point to valid data
128    // - INVALID_OPERATION: Not supported on current hardware platform
129    // - BAD_VALUE: invalid parameter
130    // NOTE: this feature is not supported on all hardware platforms and it is
131    // necessary to check returned status before using the returned values.
132    static status_t getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames,
133            audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
134
135    // return the number of input frames lost by HAL implementation, or 0 if the handle is invalid
136    static unsigned int  getInputFramesLost(audio_io_handle_t ioHandle);
137
138    static int newAudioSessionId();
139    static void acquireAudioSessionId(int audioSession);
140    static void releaseAudioSessionId(int audioSession);
141
142    // types of io configuration change events received with ioConfigChanged()
143    enum io_config_event {
144        OUTPUT_OPENED,
145        OUTPUT_CLOSED,
146        OUTPUT_CONFIG_CHANGED,
147        INPUT_OPENED,
148        INPUT_CLOSED,
149        INPUT_CONFIG_CHANGED,
150        STREAM_CONFIG_CHANGED,
151        NUM_CONFIG_EVENTS
152    };
153
154    // audio output descriptor used to cache output configurations in client process to avoid
155    // frequent calls through IAudioFlinger
156    class OutputDescriptor {
157    public:
158        OutputDescriptor()
159        : samplingRate(0), format(AUDIO_FORMAT_DEFAULT), channels(0), frameCount(0), latency(0)  {}
160
161        uint32_t samplingRate;
162        int32_t format;
163        int32_t channels;
164        size_t frameCount;
165        uint32_t latency;
166    };
167
168    // Events used to synchronize actions between audio sessions.
169    // For instance SYNC_EVENT_PRESENTATION_COMPLETE can be used to delay recording start until
170    // playback is complete on another audio session.
171    // See definitions in MediaSyncEvent.java
172    enum sync_event_t {
173        SYNC_EVENT_SAME = -1,             // used internally to indicate restart with same event
174        SYNC_EVENT_NONE = 0,
175        SYNC_EVENT_PRESENTATION_COMPLETE,
176
177        //
178        // Define new events here: SYNC_EVENT_START, SYNC_EVENT_STOP, SYNC_EVENT_TIME ...
179        //
180        SYNC_EVENT_CNT,
181    };
182
183    // Timeout for synchronous record start. Prevents from blocking the record thread forever
184    // if the trigger event is not fired.
185    static const uint32_t kSyncRecordStartTimeOutMs = 30000;
186
187    //
188    // IAudioPolicyService interface (see AudioPolicyInterface for method descriptions)
189    //
190    static status_t setDeviceConnectionState(audio_devices_t device, audio_policy_dev_state_t state,
191                                                const char *device_address);
192    static audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device,
193                                                                const char *device_address);
194    static status_t setPhoneState(audio_mode_t state);
195    static status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
196    static audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
197    static audio_io_handle_t getOutput(audio_stream_type_t stream,
198                                        uint32_t samplingRate = 0,
199                                        audio_format_t format = AUDIO_FORMAT_DEFAULT,
200                                        audio_channel_mask_t channelMask = AUDIO_CHANNEL_OUT_STEREO,
201                                        audio_output_flags_t flags = AUDIO_OUTPUT_FLAG_NONE);
202    static status_t startOutput(audio_io_handle_t output,
203                                audio_stream_type_t stream,
204                                int session = 0);
205    static status_t stopOutput(audio_io_handle_t output,
206                               audio_stream_type_t stream,
207                               int session = 0);
208    static void releaseOutput(audio_io_handle_t output);
209    static audio_io_handle_t getInput(audio_source_t inputSource,
210                                    uint32_t samplingRate = 0,
211                                    audio_format_t format = AUDIO_FORMAT_DEFAULT,
212                                    audio_channel_mask_t channelMask = AUDIO_CHANNEL_IN_MONO,
213                                    int sessionId = 0);
214    static status_t startInput(audio_io_handle_t input);
215    static status_t stopInput(audio_io_handle_t input);
216    static void releaseInput(audio_io_handle_t input);
217    static status_t initStreamVolume(audio_stream_type_t stream,
218                                      int indexMin,
219                                      int indexMax);
220    static status_t setStreamVolumeIndex(audio_stream_type_t stream,
221                                         int index,
222                                         audio_devices_t device);
223    static status_t getStreamVolumeIndex(audio_stream_type_t stream,
224                                         int *index,
225                                         audio_devices_t device);
226
227    static uint32_t getStrategyForStream(audio_stream_type_t stream);
228    static audio_devices_t getDevicesForStream(audio_stream_type_t stream);
229
230    static audio_io_handle_t getOutputForEffect(const effect_descriptor_t *desc);
231    static status_t registerEffect(const effect_descriptor_t *desc,
232                                    audio_io_handle_t io,
233                                    uint32_t strategy,
234                                    int session,
235                                    int id);
236    static status_t unregisterEffect(int id);
237    static status_t setEffectEnabled(int id, bool enabled);
238
239    // clear stream to output mapping cache (gStreamOutputMap)
240    // and output configuration cache (gOutputs)
241    static void clearAudioConfigCache();
242
243    static const sp<IAudioPolicyService>& get_audio_policy_service();
244
245    // helpers for android.media.AudioManager.getProperty(), see description there for meaning
246    static int32_t getPrimaryOutputSamplingRate();
247    static int32_t getPrimaryOutputFrameCount();
248
249    // ----------------------------------------------------------------------------
250
251private:
252
253    class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
254    {
255    public:
256        AudioFlingerClient() {
257        }
258
259        // DeathRecipient
260        virtual void binderDied(const wp<IBinder>& who);
261
262        // IAudioFlingerClient
263
264        // indicate a change in the configuration of an output or input: keeps the cached
265        // values for output/input parameters up-to-date in client process
266        virtual void ioConfigChanged(int event, audio_io_handle_t ioHandle, const void *param2);
267    };
268
269    class AudioPolicyServiceClient: public IBinder::DeathRecipient
270    {
271    public:
272        AudioPolicyServiceClient() {
273        }
274
275        // DeathRecipient
276        virtual void binderDied(const wp<IBinder>& who);
277    };
278
279    static sp<AudioFlingerClient> gAudioFlingerClient;
280    static sp<AudioPolicyServiceClient> gAudioPolicyServiceClient;
281    friend class AudioFlingerClient;
282    friend class AudioPolicyServiceClient;
283
284    static Mutex gLock;
285    static sp<IAudioFlinger> gAudioFlinger;
286    static audio_error_callback gAudioErrorCallback;
287
288    static size_t gInBuffSize;
289    // previous parameters for recording buffer size queries
290    static uint32_t gPrevInSamplingRate;
291    static audio_format_t gPrevInFormat;
292    static audio_channel_mask_t gPrevInChannelMask;
293
294    static sp<IAudioPolicyService> gAudioPolicyService;
295
296    // mapping between stream types and outputs
297    static DefaultKeyedVector<audio_stream_type_t, audio_io_handle_t> gStreamOutputMap;
298    // list of output descriptors containing cached parameters
299    // (sampling rate, framecount, channel count...)
300    static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
301};
302
303};  // namespace android
304
305#endif  /*ANDROID_AUDIOSYSTEM_H_*/
306