1 /* 2 * Copyright (C) 2011 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 18 #ifndef ANDROID_AUDIO_POLICY_INTERFACE_H 19 #define ANDROID_AUDIO_POLICY_INTERFACE_H 20 21 #include <stdint.h> 22 #include <sys/cdefs.h> 23 #include <sys/types.h> 24 25 #include <hardware/hardware.h> 26 27 #include <system/audio.h> 28 #include <system/audio_policy.h> 29 30 __BEGIN_DECLS 31 32 /** 33 * The id of this module 34 */ 35 #define AUDIO_POLICY_HARDWARE_MODULE_ID "audio_policy" 36 37 /** 38 * Name of the audio devices to open 39 */ 40 #define AUDIO_POLICY_INTERFACE "policy" 41 42 /* ---------------------------------------------------------------------------- */ 43 44 /* 45 * The audio_policy and audio_policy_service_ops structs define the 46 * communication interfaces between the platform specific audio policy manager 47 * and Android generic audio policy manager. 48 * The platform specific audio policy manager must implement methods of the 49 * audio_policy struct. 50 * This implementation makes use of the audio_policy_service_ops to control 51 * the activity and configuration of audio input and output streams. 52 * 53 * The platform specific audio policy manager is in charge of the audio 54 * routing and volume control policies for a given platform. 55 * The main roles of this module are: 56 * - keep track of current system state (removable device connections, phone 57 * state, user requests...). 58 * System state changes and user actions are notified to audio policy 59 * manager with methods of the audio_policy. 60 * 61 * - process get_output() queries received when AudioTrack objects are 62 * created: Those queries return a handler on an output that has been 63 * selected, configured and opened by the audio policy manager and that 64 * must be used by the AudioTrack when registering to the AudioFlinger 65 * with the createTrack() method. 66 * When the AudioTrack object is released, a release_output() query 67 * is received and the audio policy manager can decide to close or 68 * reconfigure the output depending on other streams using this output and 69 * current system state. 70 * 71 * - similarly process get_input() and release_input() queries received from 72 * AudioRecord objects and configure audio inputs. 73 * - process volume control requests: the stream volume is converted from 74 * an index value (received from UI) to a float value applicable to each 75 * output as a function of platform specific settings and current output 76 * route (destination device). It also make sure that streams are not 77 * muted if not allowed (e.g. camera shutter sound in some countries). 78 */ 79 80 /* XXX: this should be defined OUTSIDE of frameworks/base */ 81 struct effect_descriptor_s; 82 83 struct audio_policy { 84 /* 85 * configuration functions 86 */ 87 88 /* indicate a change in device connection status */ 89 int (*set_device_connection_state)(struct audio_policy *pol, 90 audio_devices_t device, 91 audio_policy_dev_state_t state, 92 const char *device_address); 93 94 /* retrieve a device connection status */ 95 audio_policy_dev_state_t (*get_device_connection_state)( 96 const struct audio_policy *pol, 97 audio_devices_t device, 98 const char *device_address); 99 100 /* indicate a change in phone state. Valid phones states are defined 101 * by audio_mode_t */ 102 void (*set_phone_state)(struct audio_policy *pol, audio_mode_t state); 103 104 /* deprecated, never called (was "indicate a change in ringer mode") */ 105 void (*set_ringer_mode)(struct audio_policy *pol, uint32_t mode, 106 uint32_t mask); 107 108 /* force using a specific device category for the specified usage */ 109 void (*set_force_use)(struct audio_policy *pol, 110 audio_policy_force_use_t usage, 111 audio_policy_forced_cfg_t config); 112 113 /* retrieve current device category forced for a given usage */ 114 audio_policy_forced_cfg_t (*get_force_use)(const struct audio_policy *pol, 115 audio_policy_force_use_t usage); 116 117 /* if can_mute is true, then audio streams that are marked ENFORCED_AUDIBLE 118 * can still be muted. */ 119 void (*set_can_mute_enforced_audible)(struct audio_policy *pol, 120 bool can_mute); 121 122 /* check proper initialization */ 123 int (*init_check)(const struct audio_policy *pol); 124 125 /* 126 * Audio routing query functions 127 */ 128 129 /* request an output appropriate for playback of the supplied stream type and 130 * parameters */ 131 audio_io_handle_t (*get_output)(struct audio_policy *pol, 132 audio_stream_type_t stream, 133 uint32_t samplingRate, 134 audio_format_t format, 135 audio_channel_mask_t channelMask, 136 audio_output_flags_t flags, 137 const audio_offload_info_t *offloadInfo); 138 139 /* indicates to the audio policy manager that the output starts being used 140 * by corresponding stream. */ 141 int (*start_output)(struct audio_policy *pol, 142 audio_io_handle_t output, 143 audio_stream_type_t stream, 144 int session); 145 146 /* indicates to the audio policy manager that the output stops being used 147 * by corresponding stream. */ 148 int (*stop_output)(struct audio_policy *pol, 149 audio_io_handle_t output, 150 audio_stream_type_t stream, 151 int session); 152 153 /* releases the output. */ 154 void (*release_output)(struct audio_policy *pol, audio_io_handle_t output); 155 156 /* request an input appropriate for record from the supplied device with 157 * supplied parameters. */ 158 audio_io_handle_t (*get_input)(struct audio_policy *pol, audio_source_t inputSource, 159 uint32_t samplingRate, 160 audio_format_t format, 161 audio_channel_mask_t channelMask, 162 audio_in_acoustics_t acoustics); 163 164 /* indicates to the audio policy manager that the input starts being used */ 165 int (*start_input)(struct audio_policy *pol, audio_io_handle_t input); 166 167 /* indicates to the audio policy manager that the input stops being used. */ 168 int (*stop_input)(struct audio_policy *pol, audio_io_handle_t input); 169 170 /* releases the input. */ 171 void (*release_input)(struct audio_policy *pol, audio_io_handle_t input); 172 173 /* 174 * volume control functions 175 */ 176 177 /* initialises stream volume conversion parameters by specifying volume 178 * index range. The index range for each stream is defined by AudioService. */ 179 void (*init_stream_volume)(struct audio_policy *pol, 180 audio_stream_type_t stream, 181 int index_min, 182 int index_max); 183 184 /* sets the new stream volume at a level corresponding to the supplied 185 * index. The index is within the range specified by init_stream_volume() */ 186 int (*set_stream_volume_index)(struct audio_policy *pol, 187 audio_stream_type_t stream, 188 int index); 189 190 /* retrieve current volume index for the specified stream */ 191 int (*get_stream_volume_index)(const struct audio_policy *pol, 192 audio_stream_type_t stream, 193 int *index); 194 195 /* sets the new stream volume at a level corresponding to the supplied 196 * index for the specified device. 197 * The index is within the range specified by init_stream_volume() */ 198 int (*set_stream_volume_index_for_device)(struct audio_policy *pol, 199 audio_stream_type_t stream, 200 int index, 201 audio_devices_t device); 202 203 /* retrieve current volume index for the specified stream for the specified device */ 204 int (*get_stream_volume_index_for_device)(const struct audio_policy *pol, 205 audio_stream_type_t stream, 206 int *index, 207 audio_devices_t device); 208 209 /* return the strategy corresponding to a given stream type */ 210 uint32_t (*get_strategy_for_stream)(const struct audio_policy *pol, 211 audio_stream_type_t stream); 212 213 /* return the enabled output devices for the given stream type */ 214 audio_devices_t (*get_devices_for_stream)(const struct audio_policy *pol, 215 audio_stream_type_t stream); 216 217 /* Audio effect management */ 218 audio_io_handle_t (*get_output_for_effect)(struct audio_policy *pol, 219 const struct effect_descriptor_s *desc); 220 221 int (*register_effect)(struct audio_policy *pol, 222 const struct effect_descriptor_s *desc, 223 audio_io_handle_t output, 224 uint32_t strategy, 225 int session, 226 int id); 227 228 int (*unregister_effect)(struct audio_policy *pol, int id); 229 230 int (*set_effect_enabled)(struct audio_policy *pol, int id, bool enabled); 231 232 bool (*is_stream_active)(const struct audio_policy *pol, 233 audio_stream_type_t stream, 234 uint32_t in_past_ms); 235 236 bool (*is_stream_active_remotely)(const struct audio_policy *pol, 237 audio_stream_type_t stream, 238 uint32_t in_past_ms); 239 240 bool (*is_source_active)(const struct audio_policy *pol, 241 audio_source_t source); 242 243 /* dump state */ 244 int (*dump)(const struct audio_policy *pol, int fd); 245 246 /* check if offload is possible for given sample rate, bitrate, duration, ... */ 247 bool (*is_offload_supported)(const struct audio_policy *pol, 248 const audio_offload_info_t *info); 249 }; 250 251 /* audio hw module handle used by load_hw_module(), open_output_on_module() 252 * and open_input_on_module() */ 253 typedef int audio_module_handle_t; 254 255 struct audio_policy_service_ops { 256 /* 257 * Audio output Control functions 258 */ 259 260 /* Opens an audio output with the requested parameters. 261 * 262 * The parameter values can indicate to use the default values in case the 263 * audio policy manager has no specific requirements for the output being 264 * opened. 265 * 266 * When the function returns, the parameter values reflect the actual 267 * values used by the audio hardware output stream. 268 * 269 * The audio policy manager can check if the proposed parameters are 270 * suitable or not and act accordingly. 271 */ 272 audio_io_handle_t (*open_output)(void *service, 273 audio_devices_t *pDevices, 274 uint32_t *pSamplingRate, 275 audio_format_t *pFormat, 276 audio_channel_mask_t *pChannelMask, 277 uint32_t *pLatencyMs, 278 audio_output_flags_t flags); 279 280 /* creates a special output that is duplicated to the two outputs passed as 281 * arguments. The duplication is performed by 282 * a special mixer thread in the AudioFlinger. 283 */ 284 audio_io_handle_t (*open_duplicate_output)(void *service, 285 audio_io_handle_t output1, 286 audio_io_handle_t output2); 287 288 /* closes the output stream */ 289 int (*close_output)(void *service, audio_io_handle_t output); 290 291 /* suspends the output. 292 * 293 * When an output is suspended, the corresponding audio hardware output 294 * stream is placed in standby and the AudioTracks attached to the mixer 295 * thread are still processed but the output mix is discarded. 296 */ 297 int (*suspend_output)(void *service, audio_io_handle_t output); 298 299 /* restores a suspended output. */ 300 int (*restore_output)(void *service, audio_io_handle_t output); 301 302 /* */ 303 /* Audio input Control functions */ 304 /* */ 305 306 /* opens an audio input 307 * deprecated - new implementations should use open_input_on_module, 308 * and the acoustics parameter is ignored 309 */ 310 audio_io_handle_t (*open_input)(void *service, 311 audio_devices_t *pDevices, 312 uint32_t *pSamplingRate, 313 audio_format_t *pFormat, 314 audio_channel_mask_t *pChannelMask, 315 audio_in_acoustics_t acoustics); 316 317 /* closes an audio input */ 318 int (*close_input)(void *service, audio_io_handle_t input); 319 320 /* */ 321 /* misc control functions */ 322 /* */ 323 324 /* set a stream volume for a particular output. 325 * 326 * For the same user setting, a given stream type can have different 327 * volumes for each output (destination device) it is attached to. 328 */ 329 int (*set_stream_volume)(void *service, 330 audio_stream_type_t stream, 331 float volume, 332 audio_io_handle_t output, 333 int delay_ms); 334 335 /* reroute a given stream type to the specified output */ 336 int (*set_stream_output)(void *service, 337 audio_stream_type_t stream, 338 audio_io_handle_t output); 339 340 /* function enabling to send proprietary informations directly from audio 341 * policy manager to audio hardware interface. */ 342 void (*set_parameters)(void *service, 343 audio_io_handle_t io_handle, 344 const char *kv_pairs, 345 int delay_ms); 346 347 /* function enabling to receive proprietary informations directly from 348 * audio hardware interface to audio policy manager. 349 * 350 * Returns a pointer to a heap allocated string. The caller is responsible 351 * for freeing the memory for it using free(). 352 */ 353 354 char * (*get_parameters)(void *service, audio_io_handle_t io_handle, 355 const char *keys); 356 357 /* request the playback of a tone on the specified stream. 358 * used for instance to replace notification sounds when playing over a 359 * telephony device during a phone call. 360 */ 361 int (*start_tone)(void *service, 362 audio_policy_tone_t tone, 363 audio_stream_type_t stream); 364 365 int (*stop_tone)(void *service); 366 367 /* set down link audio volume. */ 368 int (*set_voice_volume)(void *service, 369 float volume, 370 int delay_ms); 371 372 /* move effect to the specified output */ 373 int (*move_effects)(void *service, 374 int session, 375 audio_io_handle_t src_output, 376 audio_io_handle_t dst_output); 377 378 /* loads an audio hw module. 379 * 380 * The module name passed is the base name of the HW module library, e.g "primary" or "a2dp". 381 * The function returns a handle on the module that will be used to specify a particular 382 * module when calling open_output_on_module() or open_input_on_module() 383 */ 384 audio_module_handle_t (*load_hw_module)(void *service, 385 const char *name); 386 387 /* Opens an audio output on a particular HW module. 388 * 389 * Same as open_output() but specifying a specific HW module on which the output must be opened. 390 */ 391 audio_io_handle_t (*open_output_on_module)(void *service, 392 audio_module_handle_t module, 393 audio_devices_t *pDevices, 394 uint32_t *pSamplingRate, 395 audio_format_t *pFormat, 396 audio_channel_mask_t *pChannelMask, 397 uint32_t *pLatencyMs, 398 audio_output_flags_t flags, 399 const audio_offload_info_t *offloadInfo); 400 401 /* Opens an audio input on a particular HW module. 402 * 403 * Same as open_input() but specifying a specific HW module on which the input must be opened. 404 * Also removed deprecated acoustics parameter 405 */ 406 audio_io_handle_t (*open_input_on_module)(void *service, 407 audio_module_handle_t module, 408 audio_devices_t *pDevices, 409 uint32_t *pSamplingRate, 410 audio_format_t *pFormat, 411 audio_channel_mask_t *pChannelMask); 412 413 }; 414 415 /**********************************************************************/ 416 417 /** 418 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM 419 * and the fields of this data structure must begin with hw_module_t 420 * followed by module specific information. 421 */ 422 typedef struct audio_policy_module { 423 struct hw_module_t common; 424 } audio_policy_module_t; 425 426 struct audio_policy_device { 427 struct hw_device_t common; 428 429 int (*create_audio_policy)(const struct audio_policy_device *device, 430 struct audio_policy_service_ops *aps_ops, 431 void *service, 432 struct audio_policy **ap); 433 434 int (*destroy_audio_policy)(const struct audio_policy_device *device, 435 struct audio_policy *ap); 436 }; 437 438 /** convenience API for opening and closing a supported device */ 439 440 static inline int audio_policy_dev_open(const hw_module_t* module, 441 struct audio_policy_device** device) 442 { 443 return module->methods->open(module, AUDIO_POLICY_INTERFACE, 444 (hw_device_t**)device); 445 } 446 447 static inline int audio_policy_dev_close(struct audio_policy_device* device) 448 { 449 return device->common.close(&device->common); 450 } 451 452 453 __END_DECLS 454 455 #endif // ANDROID_AUDIO_POLICY_INTERFACE_H 456
