AudioSystem.h revision 0b07b8085d7b837b4dd5f09e0c8c39408f6bdbf7 
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, int output);
59    static status_t getStreamVolume(audio_stream_type_t stream, float* volume, int output);
60
61    // mute/unmute stream
62    static status_t setStreamMute(audio_stream_type_t stream, bool mute);
63    static status_t getStreamMute(audio_stream_type_t stream, bool* mute);
64
65    // set audio mode in audio hardware
66    static status_t setMode(audio_mode_t 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(audio_stream_type_t 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, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
87    static status_t getOutputFrameCount(int* frameCount, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
88    static status_t getOutputLatency(uint32_t* latency, audio_stream_type_t stream = AUDIO_STREAM_DEFAULT);
89
90    static bool routedToA2dpOutput(audio_stream_type_t 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, audio_stream_type_t 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(audio_mode_t state);
146    static status_t setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config);
147    static audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage);
148    static audio_io_handle_t getOutput(audio_stream_type_t stream,
149                                        uint32_t samplingRate = 0,
150                                        uint32_t format = AUDIO_FORMAT_DEFAULT,
151                                        uint32_t channels = AUDIO_CHANNEL_OUT_STEREO,
152                                        audio_policy_output_flags_t flags = AUDIO_POLICY_OUTPUT_FLAG_INDIRECT);
153    static status_t startOutput(audio_io_handle_t output,
154                                audio_stream_type_t stream,
155                                int session = 0);
156    static status_t stopOutput(audio_io_handle_t output,
157                               audio_stream_type_t stream,
158                               int session = 0);
159    static void releaseOutput(audio_io_handle_t output);
160    static audio_io_handle_t getInput(int inputSource,
161                                    uint32_t samplingRate = 0,
162                                    uint32_t format = AUDIO_FORMAT_DEFAULT,
163                                    uint32_t channels = AUDIO_CHANNEL_IN_MONO,
164                                    audio_in_acoustics_t acoustics = (audio_in_acoustics_t)0,
165                                    int sessionId = 0);
166    static status_t startInput(audio_io_handle_t input);
167    static status_t stopInput(audio_io_handle_t input);
168    static void releaseInput(audio_io_handle_t input);
169    static status_t initStreamVolume(audio_stream_type_t stream,
170                                      int indexMin,
171                                      int indexMax);
172    static status_t setStreamVolumeIndex(audio_stream_type_t stream,
173                                         int index,
174                                         audio_devices_t device);
175    static status_t getStreamVolumeIndex(audio_stream_type_t stream,
176                                         int *index,
177                                         audio_devices_t device);
178
179    static uint32_t getStrategyForStream(audio_stream_type_t stream);
180    static uint32_t getDevicesForStream(audio_stream_type_t stream);
181
182    static audio_io_handle_t getOutputForEffect(effect_descriptor_t *desc);
183    static status_t registerEffect(effect_descriptor_t *desc,
184                                    audio_io_handle_t io,
185                                    uint32_t strategy,
186                                    int session,
187                                    int id);
188    static status_t unregisterEffect(int id);
189    static status_t setEffectEnabled(int id, bool enabled);
190
191    // clear stream to output mapping cache (gStreamOutputMap)
192    // and output configuration cache (gOutputs)
193    static void clearAudioConfigCache();
194
195    static const sp<IAudioPolicyService>& get_audio_policy_service();
196
197    // ----------------------------------------------------------------------------
198
199private:
200
201    class AudioFlingerClient: public IBinder::DeathRecipient, public BnAudioFlingerClient
202    {
203    public:
204        AudioFlingerClient() {
205        }
206
207        // DeathRecipient
208        virtual void binderDied(const wp<IBinder>& who);
209
210        // IAudioFlingerClient
211
212        // indicate a change in the configuration of an output or input: keeps the cached
213        // values for output/input parameters upto date in client process
214        virtual void ioConfigChanged(int event, int ioHandle, void *param2);
215    };
216
217    class AudioPolicyServiceClient: public IBinder::DeathRecipient
218    {
219    public:
220        AudioPolicyServiceClient() {
221        }
222
223        // DeathRecipient
224        virtual void binderDied(const wp<IBinder>& who);
225    };
226
227    static sp<AudioFlingerClient> gAudioFlingerClient;
228    static sp<AudioPolicyServiceClient> gAudioPolicyServiceClient;
229    friend class AudioFlingerClient;
230    friend class AudioPolicyServiceClient;
231
232    static Mutex gLock;
233    static sp<IAudioFlinger> gAudioFlinger;
234    static audio_error_callback gAudioErrorCallback;
235
236    static size_t gInBuffSize;
237    // previous parameters for recording buffer size queries
238    static uint32_t gPrevInSamplingRate;
239    static int gPrevInFormat;
240    static int gPrevInChannelCount;
241
242    static sp<IAudioPolicyService> gAudioPolicyService;
243
244    // mapping between stream types and outputs
245    static DefaultKeyedVector<int, audio_io_handle_t> gStreamOutputMap;
246    // list of output descriptors containing cached parameters
247    // (sampling rate, framecount, channel count...)
248    static DefaultKeyedVector<audio_io_handle_t, OutputDescriptor *> gOutputs;
249};
250
251};  // namespace android
252
253#endif  /*ANDROID_AUDIOSYSTEM_H_*/
254