AudioSystem.h revision 3a34befc6fb04a4945a849e8bda8b84e4bf973fe 
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(int stream, float value, int output);
59    static status_t getStreamVolume(int stream, float* volume, int output);
60
61    // mute/unmute stream
62    static status_t setStreamMute(int stream, bool mute);
63    static status_t getStreamMute(int stream, bool* mute);
64
65    // set audio mode in audio hardware (see audio_mode_t)
66    static status_t setMode(int mode);
67
68    // returns true in *state if tracks are active on the specified stream or has been active
69    // in the past inPastMs milliseconds
70    static status_t isStreamActive(int stream, bool *state, uint32_t inPastMs = 0);
71
72    // set/get audio hardware parameters. The function accepts a list of parameters
73    // key value pairs in the form: key1=value1;key2=value2;...
74    // Some keys are reserved for standard parameters (See AudioParameter class).
75    static status_t setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs);
76    static String8  getParameters(audio_io_handle_t ioHandle, const String8& keys);
77
78    static void setErrorCallback(audio_error_callback cb);
79
80    // helper function to obtain AudioFlinger service handle
81    static const sp<IAudioFlinger>& get_audio_flinger();
82
83    static float linearToLog(int volume);
84    static int logToLinear(float volume);
85
86    static status_t getOutputSamplingRate(int* samplingRate, int stream = AUDIO_STREAM_DEFAULT);
87    static status_t getOutputFrameCount(int* frameCount, int stream = AUDIO_STREAM_DEFAULT);
88    static status_t getOutputLatency(uint32_t* latency, int stream = AUDIO_STREAM_DEFAULT);
89
90    static bool routedToA2dpOutput(int streamType);
91
92    static status_t getInputBufferSize(uint32_t sampleRate, int format, int channelCount,
93        size_t* buffSize);
94
95    static status_t setVoiceVolume(float volume);
96
97    // return the number of audio frames written by AudioFlinger to audio HAL and
98    // audio dsp to DAC since the output on which the specified stream is playing
99    // has exited standby.
100    // returned status (from utils/Errors.h) can be:
101    // - NO_ERROR: successful operation, halFrames and dspFrames point to valid data
102    // - INVALID_OPERATION: Not supported on current hardware platform
103    // - BAD_VALUE: invalid parameter
104    // NOTE: this feature is not supported on all hardware platforms and it is
105    // necessary to check returned status before using the returned values.
106    static status_t getRenderPosition(uint32_t *halFrames, uint32_t *dspFrames, int stream = AUDIO_STREAM_DEFAULT);
107
108    static unsigned int  getInputFramesLost(audio_io_handle_t ioHandle);
109
110    static int newAudioSessionId();
111    static void acquireAudioSessionId(int audioSession);
112    static void releaseAudioSessionId(int audioSession);
113
114    // types of io configuration change events received with ioConfigChanged()
115    enum io_config_event {
116        OUTPUT_OPENED,
117        OUTPUT_CLOSED,
118        OUTPUT_CONFIG_CHANGED,
119        INPUT_OPENED,
120        INPUT_CLOSED,
121        INPUT_CONFIG_CHANGED,
122        STREAM_CONFIG_CHANGED,
123        NUM_CONFIG_EVENTS
124    };
125
126    // audio output descritor used to cache output configurations in client process to avoid frequent calls
127    // through IAudioFlinger
128    class OutputDescriptor {
129    public:
130        OutputDescriptor()
131        : samplingRate(0), format(0), channels(0), frameCount(0), latency(0)  {}
132
133        uint32_t samplingRate;
134        int32_t format;
135        int32_t channels;
136        size_t frameCount;
137        uint32_t latency;
138    };
139
140    //
141    // IAudioPolicyService interface (see AudioPolicyInterface for method descriptions)
142    //
143    static status_t setDeviceConnectionState(audio_devices_t device, audio_policy_dev_state_t state, const char *device_address);
144    static audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device, const char *device_address);
145    static status_t setPhoneState(int state);
146    static status_t setRingerMode(uint32_t mode, uint32_t mask);
147    static status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
148    static audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
149    static audio_io_handle_t getOutput(audio_stream_type_t stream,
150                                        uint32_t samplingRate = 0,
151                                        uint32_t format = AUDIO_FORMAT_DEFAULT,
152                                        uint32_t channels = AUDIO_CHANNEL_OUT_STEREO,
153                                        audio_policy_output_flags_t flags = AUDIO_POLICY_OUTPUT_FLAG_INDIRECT);
154    static status_t startOutput(audio_io_handle_t output,
155                                audio_stream_type_t stream,
156                                int session = 0);
157    static status_t stopOutput(audio_io_handle_t output,
158                               audio_stream_type_t stream,
159                               int session = 0);
160    static void releaseOutput(audio_io_handle_t output);
161    static audio_io_handle_t getInput(int inputSource,
162                                    uint32_t samplingRate = 0,
163                                    uint32_t format = AUDIO_FORMAT_DEFAULT,
164                                    uint32_t channels = AUDIO_CHANNEL_IN_MONO,
165                                    audio_in_acoustics_t acoustics = (audio_in_acoustics_t)0,
166                                    int sessionId = 0);
167    static status_t startInput(audio_io_handle_t input);
168    static status_t stopInput(audio_io_handle_t input);
169    static void releaseInput(audio_io_handle_t input);
170    static status_t initStreamVolume(audio_stream_type_t stream,
171                                      int indexMin,
172                                      int indexMax);
173    static status_t setStreamVolumeIndex(audio_stream_type_t stream, int index);
174    static status_t getStreamVolumeIndex(audio_stream_type_t stream, int *index);
175
176    static uint32_t getStrategyForStream(audio_stream_type_t stream);
177    static uint32_t getDevicesForStream(audio_stream_type_t stream);
178
179    static audio_io_handle_t getOutputForEffect(effect_descriptor_t *desc);
180    static status_t registerEffect(effect_descriptor_t *desc,
181                                    audio_io_handle_t io,
182                                    uint32_t strategy,
183                                    int session,
184                                    int id);
185    static status_t unregisterEffect(int id);
186
187    static const sp<IAudioPolicyService>& get_audio_policy_service();
188
189    // ----------------------------------------------------------------------------
190
191private:
192
193    class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
194    {
195    public:
196        AudioFlingerClient() {
197        }
198
199        // DeathRecipient
200        virtual void binderDied(const wp<IBinder>& who);
201
202        // IAudioFlingerClient
203
204        // indicate a change in the configuration of an output or input: keeps the cached
205        // values for output/input parameters upto date in client process
206        virtual void ioConfigChanged(int event, int ioHandle, void *param2);
207    };
208
209    class AudioPolicyServiceClient: public IBinder::DeathRecipient
210    {
211    public:
212        AudioPolicyServiceClient() {
213        }
214
215        // DeathRecipient
216        virtual void binderDied(const wp<IBinder>& who);
217    };
218
219    static sp<AudioFlingerClient> gAudioFlingerClient;
220    static sp<AudioPolicyServiceClient> gAudioPolicyServiceClient;
221    friend class AudioFlingerClient;
222    friend class AudioPolicyServiceClient;
223
224    static Mutex gLock;
225    static sp<IAudioFlinger> gAudioFlinger;
226    static audio_error_callback gAudioErrorCallback;
227
228    static size_t gInBuffSize;
229    // previous parameters for recording buffer size queries
230    static uint32_t gPrevInSamplingRate;
231    static int gPrevInFormat;
232    static int gPrevInChannelCount;
233
234    static sp<IAudioPolicyService> gAudioPolicyService;
235
236    // mapping between stream types and outputs
237    static DefaultKeyedVector<int, audio_io_handle_t> gStreamOutputMap;
238    // list of output descritor containing cached parameters (sampling rate, framecount, channel count...)
239    static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
240};
241
242};  // namespace android
243
244#endif  /*ANDROID_AUDIOSYSTEM_H_*/
245