AudioSystem.h revision 1a9ed11a472493cac7f6dfcbfac2064526a493ed 
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
74    // set/get audio hardware parameters. The function accepts a list of parameters
75    // key value pairs in the form: key1=value1;key2=value2;...
76    // Some keys are reserved for standard parameters (See AudioParameter class).
77    static status_t setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs);
78    static String8  getParameters(audio_io_handle_t ioHandle, const String8& keys);
79
80    static void setErrorCallback(audio_error_callback cb);
81
82    // helper function to obtain AudioFlinger service handle
83    static const sp<IAudioFlinger>& get_audio_flinger();
84
85    static float linearToLog(int volume);
86    static int logToLinear(float volume);
87
88    static status_t getOutputSamplingRate(int* samplingRate, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
89    static status_t getOutputFrameCount(int* frameCount, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
90    static status_t getOutputLatency(uint32_t* latency, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
91    static status_t getSamplingRate(audio_io_handle_t output,
92                                          audio_stream_type_t streamType,
93                                          int* samplingRate);
94    // returns the number of frames per audio HAL write buffer. Corresponds to
95    // audio_stream->get_buffer_size()/audio_stream_frame_size()
96    static status_t getFrameCount(audio_io_handle_t output,
97                                  audio_stream_type_t stream,
98                                  int* frameCount);
99    // returns the audio output stream latency in ms. Corresponds to
100    // audio_stream_out->get_latency()
101    static status_t getLatency(audio_io_handle_t output,
102                               audio_stream_type_t stream,
103                               uint32_t* latency);
104
105    // DEPRECATED
106    static status_t getOutputSamplingRate(int* samplingRate, int stream = AUDIO_STREAM_DEFAULT);
107
108    // DEPRECATED
109    static status_t getOutputFrameCount(int* frameCount, int stream = AUDIO_STREAM_DEFAULT);
110
111    static bool routedToA2dpOutput(audio_stream_type_t streamType);
112
113    static status_t getInputBufferSize(uint32_t sampleRate, audio_format_t format, int channelCount,
114        size_t* buffSize);
115
116    static status_t setVoiceVolume(float volume);
117
118    // return the number of audio frames written by AudioFlinger to audio HAL and
119    // audio dsp to DAC since the output on which the specified stream is playing
120    // has exited standby.
121    // returned status (from utils/Errors.h) can be:
122    // - NO_ERROR: successful operation, halFrames and dspFrames point to valid data
123    // - INVALID_OPERATION: Not supported on current hardware platform
124    // - BAD_VALUE: invalid parameter
125    // NOTE: this feature is not supported on all hardware platforms and it is
126    // necessary to check returned status before using the returned values.
127    static status_t getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
128
129    static unsigned int  getInputFramesLost(audio_io_handle_t ioHandle);
130
131    static int newAudioSessionId();
132    static void acquireAudioSessionId(int audioSession);
133    static void releaseAudioSessionId(int audioSession);
134
135    // types of io configuration change events received with ioConfigChanged()
136    enum io_config_event {
137        OUTPUT_OPENED,
138        OUTPUT_CLOSED,
139        OUTPUT_CONFIG_CHANGED,
140        INPUT_OPENED,
141        INPUT_CLOSED,
142        INPUT_CONFIG_CHANGED,
143        STREAM_CONFIG_CHANGED,
144        NUM_CONFIG_EVENTS
145    };
146
147    // audio output descriptor used to cache output configurations in client process to avoid frequent calls
148    // through IAudioFlinger
149    class OutputDescriptor {
150    public:
151        OutputDescriptor()
152        : samplingRate(0), format(AUDIO_FORMAT_DEFAULT), channels(0), frameCount(0), latency(0)  {}
153
154        uint32_t samplingRate;
155        int32_t format;
156        int32_t channels;
157        size_t frameCount;
158        uint32_t latency;
159    };
160
161    // Events used to synchronize actions between audio sessions.
162    // For instance SYNC_EVENT_PRESENTATION_COMPLETE can be used to delay recording start until playback
163    // is complete on another audio session.
164    // See definitions in MediaSyncEvent.java
165    enum sync_event_t {
166        SYNC_EVENT_SAME = -1,             // used internally to indicate restart with same event
167        SYNC_EVENT_NONE = 0,
168        SYNC_EVENT_PRESENTATION_COMPLETE,
169
170        //
171        // Define new events here: SYNC_EVENT_START, SYNC_EVENT_STOP, SYNC_EVENT_TIME ...
172        //
173        SYNC_EVENT_CNT,
174    };
175
176    //
177    // IAudioPolicyService interface (see AudioPolicyInterface for method descriptions)
178    //
179    static status_t setDeviceConnectionState(audio_devices_t device, audio_policy_dev_state_t state, const char *device_address);
180    static audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device, const char *device_address);
181    static status_t setPhoneState(audio_mode_t state);
182    static status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
183    static audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
184    static audio_io_handle_t getOutput(audio_stream_type_t stream,
185                                        uint32_t samplingRate = 0,
186                                        audio_format_t format = AUDIO_FORMAT_DEFAULT,
187                                        uint32_t channels = AUDIO_CHANNEL_OUT_STEREO,
188                                        audio_policy_output_flags_t flags = AUDIO_POLICY_OUTPUT_FLAG_NONE);
189    static status_t startOutput(audio_io_handle_t output,
190                                audio_stream_type_t stream,
191                                int session = 0);
192    static status_t stopOutput(audio_io_handle_t output,
193                               audio_stream_type_t stream,
194                               int session = 0);
195    static void releaseOutput(audio_io_handle_t output);
196    static audio_io_handle_t getInput(audio_source_t inputSource,
197                                    uint32_t samplingRate = 0,
198                                    audio_format_t format = AUDIO_FORMAT_DEFAULT,
199                                    uint32_t channels = AUDIO_CHANNEL_IN_MONO,
200                                    audio_in_acoustics_t acoustics = (audio_in_acoustics_t)0,
201                                    int sessionId = 0);
202    static status_t startInput(audio_io_handle_t input);
203    static status_t stopInput(audio_io_handle_t input);
204    static void releaseInput(audio_io_handle_t input);
205    static status_t initStreamVolume(audio_stream_type_t stream,
206                                      int indexMin,
207                                      int indexMax);
208    static status_t setStreamVolumeIndex(audio_stream_type_t stream,
209                                         int index,
210                                         audio_devices_t device);
211    static status_t getStreamVolumeIndex(audio_stream_type_t stream,
212                                         int *index,
213                                         audio_devices_t device);
214
215    static uint32_t getStrategyForStream(audio_stream_type_t stream);
216    static audio_devices_t getDevicesForStream(audio_stream_type_t stream);
217
218    static audio_io_handle_t getOutputForEffect(effect_descriptor_t *desc);
219    static status_t registerEffect(effect_descriptor_t *desc,
220                                    audio_io_handle_t io,
221                                    uint32_t strategy,
222                                    int session,
223                                    int id);
224    static status_t unregisterEffect(int id);
225    static status_t setEffectEnabled(int id, bool enabled);
226
227    // clear stream to output mapping cache (gStreamOutputMap)
228    // and output configuration cache (gOutputs)
229    static void clearAudioConfigCache();
230
231    static const sp<IAudioPolicyService>& get_audio_policy_service();
232
233    // ----------------------------------------------------------------------------
234
235private:
236
237    class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
238    {
239    public:
240        AudioFlingerClient() {
241        }
242
243        // DeathRecipient
244        virtual void binderDied(const wp<IBinder>& who);
245
246        // IAudioFlingerClient
247
248        // indicate a change in the configuration of an output or input: keeps the cached
249        // values for output/input parameters up-to-date in client process
250        virtual void ioConfigChanged(int event, audio_io_handle_t ioHandle, const void *param2);
251    };
252
253    class AudioPolicyServiceClient: public IBinder::DeathRecipient
254    {
255    public:
256        AudioPolicyServiceClient() {
257        }
258
259        // DeathRecipient
260        virtual void binderDied(const wp<IBinder>& who);
261    };
262
263    static sp<AudioFlingerClient> gAudioFlingerClient;
264    static sp<AudioPolicyServiceClient> gAudioPolicyServiceClient;
265    friend class AudioFlingerClient;
266    friend class AudioPolicyServiceClient;
267
268    static Mutex gLock;
269    static sp<IAudioFlinger> gAudioFlinger;
270    static audio_error_callback gAudioErrorCallback;
271
272    static size_t gInBuffSize;
273    // previous parameters for recording buffer size queries
274    static uint32_t gPrevInSamplingRate;
275    static audio_format_t gPrevInFormat;
276    static int gPrevInChannelCount;
277
278    static sp<IAudioPolicyService> gAudioPolicyService;
279
280    // mapping between stream types and outputs
281    static DefaultKeyedVector<audio_stream_type_t, audio_io_handle_t> gStreamOutputMap;
282    // list of output descriptors containing cached parameters
283    // (sampling rate, framecount, channel count...)
284    static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
285};
286
287};  // namespace android
288
289#endif  /*ANDROID_AUDIOSYSTEM_H_*/
290