1/*
2 * Copyright (C) 2009 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_AUDIOPOLICY_INTERFACE_H
18#define ANDROID_AUDIOPOLICY_INTERFACE_H
19
20#include <media/AudioSystem.h>
21#include <media/AudioPolicy.h>
22#include <utils/String8.h>
23
24#include <hardware/audio_policy.h>
25
26namespace android {
27
28// ----------------------------------------------------------------------------
29
30// The AudioPolicyInterface and AudioPolicyClientInterface classes define the communication interfaces
31// between the platform specific audio policy manager and Android generic audio policy manager.
32// The platform specific audio policy manager must implement methods of the AudioPolicyInterface class.
33// This implementation makes use of the AudioPolicyClientInterface to control the activity and
34// configuration of audio input and output streams.
35//
36// The platform specific audio policy manager is in charge of the audio routing and volume control
37// policies for a given platform.
38// The main roles of this module are:
39//   - keep track of current system state (removable device connections, phone state, user requests...).
40//   System state changes and user actions are notified to audio policy manager with methods of the AudioPolicyInterface.
41//   - process getOutput() queries received when AudioTrack objects are created: Those queries
42//   return a handler on an output that has been selected, configured and opened by the audio policy manager and that
43//   must be used by the AudioTrack when registering to the AudioFlinger with the createTrack() method.
44//   When the AudioTrack object is released, a putOutput() query is received and the audio policy manager can decide
45//   to close or reconfigure the output depending on other streams using this output and current system state.
46//   - similarly process getInput() and putInput() queries received from AudioRecord objects and configure audio inputs.
47//   - process volume control requests: the stream volume is converted from an index value (received from UI) to a float value
48//   applicable to each output as a function of platform specific settings and current output route (destination device). It
49//   also make sure that streams are not muted if not allowed (e.g. camera shutter sound in some countries).
50//
51// The platform specific audio policy manager is provided as a shared library by platform vendors (as for libaudio.so)
52// and is linked with libaudioflinger.so
53
54
55//    Audio Policy Manager Interface
56class AudioPolicyInterface
57{
58
59public:
60    typedef enum {
61        API_INPUT_INVALID = -1,
62        API_INPUT_LEGACY  = 0,// e.g. audio recording from a microphone
63        API_INPUT_MIX_CAPTURE,// used for "remote submix", capture of the media to play it remotely
64        API_INPUT_MIX_EXT_POLICY_REROUTE,// used for platform audio rerouting, where mixes are
65                                         // handled by external and dynamically installed
66                                         // policies which reroute audio mixes
67    } input_type_t;
68
69public:
70    virtual ~AudioPolicyInterface() {}
71    //
72    // configuration functions
73    //
74
75    // indicate a change in device connection status
76    virtual status_t setDeviceConnectionState(audio_devices_t device,
77                                              audio_policy_dev_state_t state,
78                                          const char *device_address) = 0;
79    // retrieve a device connection status
80    virtual audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device,
81                                                                          const char *device_address) = 0;
82    // indicate a change in phone state. Valid phones states are defined by audio_mode_t
83    virtual void setPhoneState(audio_mode_t state) = 0;
84    // force using a specific device category for the specified usage
85    virtual void setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config) = 0;
86    // retrieve current device category forced for a given usage
87    virtual audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage) = 0;
88    // set a system property (e.g. camera sound always audible)
89    virtual void setSystemProperty(const char* property, const char* value) = 0;
90    // check proper initialization
91    virtual status_t initCheck() = 0;
92
93    //
94    // Audio routing query functions
95    //
96
97    // request an output appropriate for playback of the supplied stream type and parameters
98    virtual audio_io_handle_t getOutput(audio_stream_type_t stream,
99                                        uint32_t samplingRate,
100                                        audio_format_t format,
101                                        audio_channel_mask_t channelMask,
102                                        audio_output_flags_t flags,
103                                        const audio_offload_info_t *offloadInfo) = 0;
104    virtual status_t getOutputForAttr(const audio_attributes_t *attr,
105                                        audio_io_handle_t *output,
106                                        audio_session_t session,
107                                        audio_stream_type_t *stream,
108                                        uint32_t samplingRate,
109                                        audio_format_t format,
110                                        audio_channel_mask_t channelMask,
111                                        audio_output_flags_t flags,
112                                        const audio_offload_info_t *offloadInfo) = 0;
113    // indicates to the audio policy manager that the output starts being used by corresponding stream.
114    virtual status_t startOutput(audio_io_handle_t output,
115                                 audio_stream_type_t stream,
116                                 audio_session_t session) = 0;
117    // indicates to the audio policy manager that the output stops being used by corresponding stream.
118    virtual status_t stopOutput(audio_io_handle_t output,
119                                audio_stream_type_t stream,
120                                audio_session_t session) = 0;
121    // releases the output.
122    virtual void releaseOutput(audio_io_handle_t output,
123                               audio_stream_type_t stream,
124                               audio_session_t session) = 0;
125
126    // request an input appropriate for record from the supplied device with supplied parameters.
127    virtual status_t getInputForAttr(const audio_attributes_t *attr,
128                                     audio_io_handle_t *input,
129                                     audio_session_t session,
130                                     uint32_t samplingRate,
131                                     audio_format_t format,
132                                     audio_channel_mask_t channelMask,
133                                     audio_input_flags_t flags,
134                                     input_type_t *inputType) = 0;
135    // indicates to the audio policy manager that the input starts being used.
136    virtual status_t startInput(audio_io_handle_t input,
137                                audio_session_t session) = 0;
138    // indicates to the audio policy manager that the input stops being used.
139    virtual status_t stopInput(audio_io_handle_t input,
140                               audio_session_t session) = 0;
141    // releases the input.
142    virtual void releaseInput(audio_io_handle_t input,
143                              audio_session_t session) = 0;
144
145    //
146    // volume control functions
147    //
148
149    // initialises stream volume conversion parameters by specifying volume index range.
150    virtual void initStreamVolume(audio_stream_type_t stream,
151                                      int indexMin,
152                                      int indexMax) = 0;
153
154    // sets the new stream volume at a level corresponding to the supplied index for the
155    // supplied device. By convention, specifying AUDIO_DEVICE_OUT_DEFAULT means
156    // setting volume for all devices
157    virtual status_t setStreamVolumeIndex(audio_stream_type_t stream,
158                                          int index,
159                                          audio_devices_t device) = 0;
160
161    // retrieve current volume index for the specified stream and the
162    // specified device. By convention, specifying AUDIO_DEVICE_OUT_DEFAULT means
163    // querying the volume of the active device.
164    virtual status_t getStreamVolumeIndex(audio_stream_type_t stream,
165                                          int *index,
166                                          audio_devices_t device) = 0;
167
168    // return the strategy corresponding to a given stream type
169    virtual uint32_t getStrategyForStream(audio_stream_type_t stream) = 0;
170
171    // return the enabled output devices for the given stream type
172    virtual audio_devices_t getDevicesForStream(audio_stream_type_t stream) = 0;
173
174    // Audio effect management
175    virtual audio_io_handle_t getOutputForEffect(const effect_descriptor_t *desc) = 0;
176    virtual status_t registerEffect(const effect_descriptor_t *desc,
177                                    audio_io_handle_t io,
178                                    uint32_t strategy,
179                                    int session,
180                                    int id) = 0;
181    virtual status_t unregisterEffect(int id) = 0;
182    virtual status_t setEffectEnabled(int id, bool enabled) = 0;
183
184    virtual bool isStreamActive(audio_stream_type_t stream, uint32_t inPastMs = 0) const = 0;
185    virtual bool isStreamActiveRemotely(audio_stream_type_t stream,
186                                        uint32_t inPastMs = 0) const = 0;
187    virtual bool isSourceActive(audio_source_t source) const = 0;
188
189    //dump state
190    virtual status_t    dump(int fd) = 0;
191
192    virtual bool isOffloadSupported(const audio_offload_info_t& offloadInfo) = 0;
193
194    virtual status_t listAudioPorts(audio_port_role_t role,
195                                    audio_port_type_t type,
196                                    unsigned int *num_ports,
197                                    struct audio_port *ports,
198                                    unsigned int *generation) = 0;
199    virtual status_t getAudioPort(struct audio_port *port) = 0;
200    virtual status_t createAudioPatch(const struct audio_patch *patch,
201                                       audio_patch_handle_t *handle,
202                                       uid_t uid) = 0;
203    virtual status_t releaseAudioPatch(audio_patch_handle_t handle,
204                                          uid_t uid) = 0;
205    virtual status_t listAudioPatches(unsigned int *num_patches,
206                                      struct audio_patch *patches,
207                                      unsigned int *generation) = 0;
208    virtual status_t setAudioPortConfig(const struct audio_port_config *config) = 0;
209    virtual void clearAudioPatches(uid_t uid) = 0;
210
211    virtual status_t acquireSoundTriggerSession(audio_session_t *session,
212                                           audio_io_handle_t *ioHandle,
213                                           audio_devices_t *device) = 0;
214
215    virtual status_t releaseSoundTriggerSession(audio_session_t session) = 0;
216
217    virtual status_t registerPolicyMixes(Vector<AudioMix> mixes) = 0;
218    virtual status_t unregisterPolicyMixes(Vector<AudioMix> mixes) = 0;
219};
220
221
222// Audio Policy client Interface
223class AudioPolicyClientInterface
224{
225public:
226    virtual ~AudioPolicyClientInterface() {}
227
228    //
229    // Audio HW module functions
230    //
231
232    // loads a HW module.
233    virtual audio_module_handle_t loadHwModule(const char *name) = 0;
234
235    //
236    // Audio output Control functions
237    //
238
239    // opens an audio output with the requested parameters. The parameter values can indicate to use the default values
240    // in case the audio policy manager has no specific requirements for the output being opened.
241    // When the function returns, the parameter values reflect the actual values used by the audio hardware output stream.
242    // The audio policy manager can check if the proposed parameters are suitable or not and act accordingly.
243    virtual status_t openOutput(audio_module_handle_t module,
244                                audio_io_handle_t *output,
245                                audio_config_t *config,
246                                audio_devices_t *devices,
247                                const String8& address,
248                                uint32_t *latencyMs,
249                                audio_output_flags_t flags) = 0;
250    // creates a special output that is duplicated to the two outputs passed as arguments. The duplication is performed by
251    // a special mixer thread in the AudioFlinger.
252    virtual audio_io_handle_t openDuplicateOutput(audio_io_handle_t output1, audio_io_handle_t output2) = 0;
253    // closes the output stream
254    virtual status_t closeOutput(audio_io_handle_t output) = 0;
255    // suspends the output. When an output is suspended, the corresponding audio hardware output stream is placed in
256    // standby and the AudioTracks attached to the mixer thread are still processed but the output mix is discarded.
257    virtual status_t suspendOutput(audio_io_handle_t output) = 0;
258    // restores a suspended output.
259    virtual status_t restoreOutput(audio_io_handle_t output) = 0;
260
261    //
262    // Audio input Control functions
263    //
264
265    // opens an audio input
266    virtual status_t openInput(audio_module_handle_t module,
267                               audio_io_handle_t *input,
268                               audio_config_t *config,
269                               audio_devices_t *device,
270                               const String8& address,
271                               audio_source_t source,
272                               audio_input_flags_t flags) = 0;
273    // closes an audio input
274    virtual status_t closeInput(audio_io_handle_t input) = 0;
275    //
276    // misc control functions
277    //
278
279    // set a stream volume for a particular output. For the same user setting, a given stream type can have different volumes
280    // for each output (destination device) it is attached to.
281    virtual status_t setStreamVolume(audio_stream_type_t stream, float volume, audio_io_handle_t output, int delayMs = 0) = 0;
282
283    // invalidate a stream type, causing a reroute to an unspecified new output
284    virtual status_t invalidateStream(audio_stream_type_t stream) = 0;
285
286    // function enabling to send proprietary informations directly from audio policy manager to audio hardware interface.
287    virtual void setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs, int delayMs = 0) = 0;
288    // function enabling to receive proprietary informations directly from audio hardware interface to audio policy manager.
289    virtual String8 getParameters(audio_io_handle_t ioHandle, const String8& keys) = 0;
290
291    // request the playback of a tone on the specified stream: used for instance to replace notification sounds when playing
292    // over a telephony device during a phone call.
293    virtual status_t startTone(audio_policy_tone_t tone, audio_stream_type_t stream) = 0;
294    virtual status_t stopTone() = 0;
295
296    // set down link audio volume.
297    virtual status_t setVoiceVolume(float volume, int delayMs = 0) = 0;
298
299    // move effect to the specified output
300    virtual status_t moveEffects(int session,
301                                     audio_io_handle_t srcOutput,
302                                     audio_io_handle_t dstOutput) = 0;
303
304    /* Create a patch between several source and sink ports */
305    virtual status_t createAudioPatch(const struct audio_patch *patch,
306                                       audio_patch_handle_t *handle,
307                                       int delayMs) = 0;
308
309    /* Release a patch */
310    virtual status_t releaseAudioPatch(audio_patch_handle_t handle,
311                                       int delayMs) = 0;
312
313    /* Set audio port configuration */
314    virtual status_t setAudioPortConfig(const struct audio_port_config *config, int delayMs) = 0;
315
316    virtual void onAudioPortListUpdate() = 0;
317
318    virtual void onAudioPatchListUpdate() = 0;
319
320    virtual audio_unique_id_t newAudioUniqueId() = 0;
321};
322
323extern "C" AudioPolicyInterface* createAudioPolicyManager(AudioPolicyClientInterface *clientInterface);
324extern "C" void destroyAudioPolicyManager(AudioPolicyInterface *interface);
325
326
327}; // namespace android
328
329#endif // ANDROID_AUDIOPOLICY_INTERFACE_H
330