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 uint32_t channels, 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 uint32_t channels, 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 struct effect_descriptor_s *desc); 219 220 int (*register_effect)(struct audio_policy *pol, 221 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 /* dump state */ 236 int (*dump)(const struct audio_policy *pol, int fd); 237 }; 238 239 /* audio hw module handle used by load_hw_module(), open_output_on_module() 240 * and open_input_on_module() */ 241 typedef int audio_module_handle_t; 242 243 struct audio_policy_service_ops { 244 /* 245 * Audio output Control functions 246 */ 247 248 /* Opens an audio output with the requested parameters. 249 * 250 * The parameter values can indicate to use the default values in case the 251 * audio policy manager has no specific requirements for the output being 252 * opened. 253 * 254 * When the function returns, the parameter values reflect the actual 255 * values used by the audio hardware output stream. 256 * 257 * The audio policy manager can check if the proposed parameters are 258 * suitable or not and act accordingly. 259 */ 260 audio_io_handle_t (*open_output)(void *service, 261 audio_devices_t *pDevices, 262 uint32_t *pSamplingRate, 263 audio_format_t *pFormat, 264 audio_channel_mask_t *pChannelMask, 265 uint32_t *pLatencyMs, 266 audio_output_flags_t flags); 267 268 /* creates a special output that is duplicated to the two outputs passed as 269 * arguments. The duplication is performed by 270 * a special mixer thread in the AudioFlinger. 271 */ 272 audio_io_handle_t (*open_duplicate_output)(void *service, 273 audio_io_handle_t output1, 274 audio_io_handle_t output2); 275 276 /* closes the output stream */ 277 int (*close_output)(void *service, audio_io_handle_t output); 278 279 /* suspends the output. 280 * 281 * When an output is suspended, the corresponding audio hardware output 282 * stream is placed in standby and the AudioTracks attached to the mixer 283 * thread are still processed but the output mix is discarded. 284 */ 285 int (*suspend_output)(void *service, audio_io_handle_t output); 286 287 /* restores a suspended output. */ 288 int (*restore_output)(void *service, audio_io_handle_t output); 289 290 /* */ 291 /* Audio input Control functions */ 292 /* */ 293 294 /* opens an audio input */ 295 audio_io_handle_t (*open_input)(void *service, 296 audio_devices_t *pDevices, 297 uint32_t *pSamplingRate, 298 audio_format_t *pFormat, 299 audio_channel_mask_t *pChannelMask, 300 audio_in_acoustics_t acoustics); 301 302 /* closes an audio input */ 303 int (*close_input)(void *service, audio_io_handle_t input); 304 305 /* */ 306 /* misc control functions */ 307 /* */ 308 309 /* set a stream volume for a particular output. 310 * 311 * For the same user setting, a given stream type can have different 312 * volumes for each output (destination device) it is attached to. 313 */ 314 int (*set_stream_volume)(void *service, 315 audio_stream_type_t stream, 316 float volume, 317 audio_io_handle_t output, 318 int delay_ms); 319 320 /* reroute a given stream type to the specified output */ 321 int (*set_stream_output)(void *service, 322 audio_stream_type_t stream, 323 audio_io_handle_t output); 324 325 /* function enabling to send proprietary informations directly from audio 326 * policy manager to audio hardware interface. */ 327 void (*set_parameters)(void *service, 328 audio_io_handle_t io_handle, 329 const char *kv_pairs, 330 int delay_ms); 331 332 /* function enabling to receive proprietary informations directly from 333 * audio hardware interface to audio policy manager. 334 * 335 * Returns a pointer to a heap allocated string. The caller is responsible 336 * for freeing the memory for it using free(). 337 */ 338 339 char * (*get_parameters)(void *service, audio_io_handle_t io_handle, 340 const char *keys); 341 342 /* request the playback of a tone on the specified stream. 343 * used for instance to replace notification sounds when playing over a 344 * telephony device during a phone call. 345 */ 346 int (*start_tone)(void *service, 347 audio_policy_tone_t tone, 348 audio_stream_type_t stream); 349 350 int (*stop_tone)(void *service); 351 352 /* set down link audio volume. */ 353 int (*set_voice_volume)(void *service, 354 float volume, 355 int delay_ms); 356 357 /* move effect to the specified output */ 358 int (*move_effects)(void *service, 359 int session, 360 audio_io_handle_t src_output, 361 audio_io_handle_t dst_output); 362 363 /* loads an audio hw module. 364 * 365 * The module name passed is the base name of the HW module library, e.g "primary" or "a2dp". 366 * The function returns a handle on the module that will be used to specify a particular 367 * module when calling open_output_on_module() or open_input_on_module() 368 */ 369 audio_module_handle_t (*load_hw_module)(void *service, 370 const char *name); 371 372 /* Opens an audio output on a particular HW module. 373 * 374 * Same as open_output() but specifying a specific HW module on which the output must be opened. 375 */ 376 audio_io_handle_t (*open_output_on_module)(void *service, 377 audio_module_handle_t module, 378 audio_devices_t *pDevices, 379 uint32_t *pSamplingRate, 380 audio_format_t *pFormat, 381 audio_channel_mask_t *pChannelMask, 382 uint32_t *pLatencyMs, 383 audio_output_flags_t flags); 384 385 /* Opens an audio input on a particular HW module. 386 * 387 * Same as open_input() but specifying a specific HW module on which the input must be opened. 388 * Also removed deprecated acoustics parameter 389 */ 390 audio_io_handle_t (*open_input_on_module)(void *service, 391 audio_module_handle_t module, 392 audio_devices_t *pDevices, 393 uint32_t *pSamplingRate, 394 audio_format_t *pFormat, 395 audio_channel_mask_t *pChannelMask); 396 397 }; 398 399 /**********************************************************************/ 400 401 /** 402 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM 403 * and the fields of this data structure must begin with hw_module_t 404 * followed by module specific information. 405 */ 406 typedef struct audio_policy_module { 407 struct hw_module_t common; 408 } audio_policy_module_t; 409 410 struct audio_policy_device { 411 struct hw_device_t common; 412 413 int (*create_audio_policy)(const struct audio_policy_device *device, 414 struct audio_policy_service_ops *aps_ops, 415 void *service, 416 struct audio_policy **ap); 417 418 int (*destroy_audio_policy)(const struct audio_policy_device *device, 419 struct audio_policy *ap); 420 }; 421 422 /** convenience API for opening and closing a supported device */ 423 424 static inline int audio_policy_dev_open(const hw_module_t* module, 425 struct audio_policy_device** device) 426 { 427 return module->methods->open(module, AUDIO_POLICY_INTERFACE, 428 (hw_device_t**)device); 429 } 430 431 static inline int audio_policy_dev_close(struct audio_policy_device* device) 432 { 433 return device->common.close(&device->common); 434 } 435 436 437 __END_DECLS 438 439 #endif // ANDROID_AUDIO_POLICY_INTERFACE_H 440
