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); 137 138 /* indicates to the audio policy manager that the output starts being used 139 * by corresponding stream. */ 140 int (*start_output)(struct audio_policy *pol, 141 audio_io_handle_t output, 142 audio_stream_type_t stream, 143 int session); 144 145 /* indicates to the audio policy manager that the output stops being used 146 * by corresponding stream. */ 147 int (*stop_output)(struct audio_policy *pol, 148 audio_io_handle_t output, 149 audio_stream_type_t stream, 150 int session); 151 152 /* releases the output. */ 153 void (*release_output)(struct audio_policy *pol, audio_io_handle_t output); 154 155 /* request an input appropriate for record from the supplied device with 156 * supplied parameters. */ 157 audio_io_handle_t (*get_input)(struct audio_policy *pol, audio_source_t inputSource, 158 uint32_t samplingRate, 159 audio_format_t format, 160 audio_channel_mask_t channelMask, 161 audio_in_acoustics_t acoustics); 162 163 /* indicates to the audio policy manager that the input starts being used */ 164 int (*start_input)(struct audio_policy *pol, audio_io_handle_t input); 165 166 /* indicates to the audio policy manager that the input stops being used. */ 167 int (*stop_input)(struct audio_policy *pol, audio_io_handle_t input); 168 169 /* releases the input. */ 170 void (*release_input)(struct audio_policy *pol, audio_io_handle_t input); 171 172 /* 173 * volume control functions 174 */ 175 176 /* initialises stream volume conversion parameters by specifying volume 177 * index range. The index range for each stream is defined by AudioService. */ 178 void (*init_stream_volume)(struct audio_policy *pol, 179 audio_stream_type_t stream, 180 int index_min, 181 int index_max); 182 183 /* sets the new stream volume at a level corresponding to the supplied 184 * index. The index is within the range specified by init_stream_volume() */ 185 int (*set_stream_volume_index)(struct audio_policy *pol, 186 audio_stream_type_t stream, 187 int index); 188 189 /* retrieve current volume index for the specified stream */ 190 int (*get_stream_volume_index)(const struct audio_policy *pol, 191 audio_stream_type_t stream, 192 int *index); 193 194 /* sets the new stream volume at a level corresponding to the supplied 195 * index for the specified device. 196 * The index is within the range specified by init_stream_volume() */ 197 int (*set_stream_volume_index_for_device)(struct audio_policy *pol, 198 audio_stream_type_t stream, 199 int index, 200 audio_devices_t device); 201 202 /* retrieve current volume index for the specified stream for the specified device */ 203 int (*get_stream_volume_index_for_device)(const struct audio_policy *pol, 204 audio_stream_type_t stream, 205 int *index, 206 audio_devices_t device); 207 208 /* return the strategy corresponding to a given stream type */ 209 uint32_t (*get_strategy_for_stream)(const struct audio_policy *pol, 210 audio_stream_type_t stream); 211 212 /* return the enabled output devices for the given stream type */ 213 audio_devices_t (*get_devices_for_stream)(const struct audio_policy *pol, 214 audio_stream_type_t stream); 215 216 /* Audio effect management */ 217 audio_io_handle_t (*get_output_for_effect)(struct audio_policy *pol, 218 const struct effect_descriptor_s *desc); 219 220 int (*register_effect)(struct audio_policy *pol, 221 const struct effect_descriptor_s *desc, 222 audio_io_handle_t output, 223 uint32_t strategy, 224 int session, 225 int id); 226 227 int (*unregister_effect)(struct audio_policy *pol, int id); 228 229 int (*set_effect_enabled)(struct audio_policy *pol, int id, bool enabled); 230 231 bool (*is_stream_active)(const struct audio_policy *pol, 232 audio_stream_type_t stream, 233 uint32_t in_past_ms); 234 235 bool (*is_stream_active_remotely)(const struct audio_policy *pol, 236 audio_stream_type_t stream, 237 uint32_t in_past_ms); 238 239 bool (*is_source_active)(const struct audio_policy *pol, 240 audio_source_t source); 241 242 /* dump state */ 243 int (*dump)(const struct audio_policy *pol, int fd); 244 }; 245 246 /* audio hw module handle used by load_hw_module(), open_output_on_module() 247 * and open_input_on_module() */ 248 typedef int audio_module_handle_t; 249 250 struct audio_policy_service_ops { 251 /* 252 * Audio output Control functions 253 */ 254 255 /* Opens an audio output with the requested parameters. 256 * 257 * The parameter values can indicate to use the default values in case the 258 * audio policy manager has no specific requirements for the output being 259 * opened. 260 * 261 * When the function returns, the parameter values reflect the actual 262 * values used by the audio hardware output stream. 263 * 264 * The audio policy manager can check if the proposed parameters are 265 * suitable or not and act accordingly. 266 */ 267 audio_io_handle_t (*open_output)(void *service, 268 audio_devices_t *pDevices, 269 uint32_t *pSamplingRate, 270 audio_format_t *pFormat, 271 audio_channel_mask_t *pChannelMask, 272 uint32_t *pLatencyMs, 273 audio_output_flags_t flags); 274 275 /* creates a special output that is duplicated to the two outputs passed as 276 * arguments. The duplication is performed by 277 * a special mixer thread in the AudioFlinger. 278 */ 279 audio_io_handle_t (*open_duplicate_output)(void *service, 280 audio_io_handle_t output1, 281 audio_io_handle_t output2); 282 283 /* closes the output stream */ 284 int (*close_output)(void *service, audio_io_handle_t output); 285 286 /* suspends the output. 287 * 288 * When an output is suspended, the corresponding audio hardware output 289 * stream is placed in standby and the AudioTracks attached to the mixer 290 * thread are still processed but the output mix is discarded. 291 */ 292 int (*suspend_output)(void *service, audio_io_handle_t output); 293 294 /* restores a suspended output. */ 295 int (*restore_output)(void *service, audio_io_handle_t output); 296 297 /* */ 298 /* Audio input Control functions */ 299 /* */ 300 301 /* opens an audio input 302 * deprecated - new implementations should use open_input_on_module, 303 * and the acoustics parameter is ignored 304 */ 305 audio_io_handle_t (*open_input)(void *service, 306 audio_devices_t *pDevices, 307 uint32_t *pSamplingRate, 308 audio_format_t *pFormat, 309 audio_channel_mask_t *pChannelMask, 310 audio_in_acoustics_t acoustics); 311 312 /* closes an audio input */ 313 int (*close_input)(void *service, audio_io_handle_t input); 314 315 /* */ 316 /* misc control functions */ 317 /* */ 318 319 /* set a stream volume for a particular output. 320 * 321 * For the same user setting, a given stream type can have different 322 * volumes for each output (destination device) it is attached to. 323 */ 324 int (*set_stream_volume)(void *service, 325 audio_stream_type_t stream, 326 float volume, 327 audio_io_handle_t output, 328 int delay_ms); 329 330 /* reroute a given stream type to the specified output */ 331 int (*set_stream_output)(void *service, 332 audio_stream_type_t stream, 333 audio_io_handle_t output); 334 335 /* function enabling to send proprietary informations directly from audio 336 * policy manager to audio hardware interface. */ 337 void (*set_parameters)(void *service, 338 audio_io_handle_t io_handle, 339 const char *kv_pairs, 340 int delay_ms); 341 342 /* function enabling to receive proprietary informations directly from 343 * audio hardware interface to audio policy manager. 344 * 345 * Returns a pointer to a heap allocated string. The caller is responsible 346 * for freeing the memory for it using free(). 347 */ 348 349 char * (*get_parameters)(void *service, audio_io_handle_t io_handle, 350 const char *keys); 351 352 /* request the playback of a tone on the specified stream. 353 * used for instance to replace notification sounds when playing over a 354 * telephony device during a phone call. 355 */ 356 int (*start_tone)(void *service, 357 audio_policy_tone_t tone, 358 audio_stream_type_t stream); 359 360 int (*stop_tone)(void *service); 361 362 /* set down link audio volume. */ 363 int (*set_voice_volume)(void *service, 364 float volume, 365 int delay_ms); 366 367 /* move effect to the specified output */ 368 int (*move_effects)(void *service, 369 int session, 370 audio_io_handle_t src_output, 371 audio_io_handle_t dst_output); 372 373 /* loads an audio hw module. 374 * 375 * The module name passed is the base name of the HW module library, e.g "primary" or "a2dp". 376 * The function returns a handle on the module that will be used to specify a particular 377 * module when calling open_output_on_module() or open_input_on_module() 378 */ 379 audio_module_handle_t (*load_hw_module)(void *service, 380 const char *name); 381 382 /* Opens an audio output on a particular HW module. 383 * 384 * Same as open_output() but specifying a specific HW module on which the output must be opened. 385 */ 386 audio_io_handle_t (*open_output_on_module)(void *service, 387 audio_module_handle_t module, 388 audio_devices_t *pDevices, 389 uint32_t *pSamplingRate, 390 audio_format_t *pFormat, 391 audio_channel_mask_t *pChannelMask, 392 uint32_t *pLatencyMs, 393 audio_output_flags_t flags); 394 395 /* Opens an audio input on a particular HW module. 396 * 397 * Same as open_input() but specifying a specific HW module on which the input must be opened. 398 * Also removed deprecated acoustics parameter 399 */ 400 audio_io_handle_t (*open_input_on_module)(void *service, 401 audio_module_handle_t module, 402 audio_devices_t *pDevices, 403 uint32_t *pSamplingRate, 404 audio_format_t *pFormat, 405 audio_channel_mask_t *pChannelMask); 406 407 }; 408 409 /**********************************************************************/ 410 411 /** 412 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM 413 * and the fields of this data structure must begin with hw_module_t 414 * followed by module specific information. 415 */ 416 typedef struct audio_policy_module { 417 struct hw_module_t common; 418 } audio_policy_module_t; 419 420 struct audio_policy_device { 421 struct hw_device_t common; 422 423 int (*create_audio_policy)(const struct audio_policy_device *device, 424 struct audio_policy_service_ops *aps_ops, 425 void *service, 426 struct audio_policy **ap); 427 428 int (*destroy_audio_policy)(const struct audio_policy_device *device, 429 struct audio_policy *ap); 430 }; 431 432 /** convenience API for opening and closing a supported device */ 433 434 static inline int audio_policy_dev_open(const hw_module_t* module, 435 struct audio_policy_device** device) 436 { 437 return module->methods->open(module, AUDIO_POLICY_INTERFACE, 438 (hw_device_t**)device); 439 } 440 441 static inline int audio_policy_dev_close(struct audio_policy_device* device) 442 { 443 return device->common.close(&device->common); 444 } 445 446 447 __END_DECLS 448 449 #endif // ANDROID_AUDIO_POLICY_INTERFACE_H 450
