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 /* retreive 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, int state); 103 104 /* 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 /* retreive 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 appriate 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 uint32_t format, 135 uint32_t channels, 136 audio_policy_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 appriate for record from the supplied device with 156 * supplied parameters. */ 157 audio_io_handle_t (*get_input)(struct audio_policy *pol, int inputSource, 158 uint32_t samplingRate, 159 uint32_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. */ 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 */ 185 int (*set_stream_volume_index)(struct audio_policy *pol, 186 audio_stream_type_t stream, 187 int index); 188 189 /* retreive 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 /* return the strategy corresponding to a given stream type */ 195 uint32_t (*get_strategy_for_stream)(const struct audio_policy *pol, 196 audio_stream_type_t stream); 197 198 /* return the enabled output devices for the given stream type */ 199 uint32_t (*get_devices_for_stream)(const struct audio_policy *pol, 200 audio_stream_type_t stream); 201 202 /* Audio effect management */ 203 audio_io_handle_t (*get_output_for_effect)(struct audio_policy *pol, 204 struct effect_descriptor_s *desc); 205 206 int (*register_effect)(struct audio_policy *pol, 207 struct effect_descriptor_s *desc, 208 audio_io_handle_t output, 209 uint32_t strategy, 210 int session, 211 int id); 212 213 int (*unregister_effect)(struct audio_policy *pol, int id); 214 215 int (*set_effect_enabled)(struct audio_policy *pol, int id, bool enabled); 216 217 bool (*is_stream_active)(const struct audio_policy *pol, 218 int stream, 219 uint32_t in_past_ms); 220 221 /* dump state */ 222 int (*dump)(const struct audio_policy *pol, int fd); 223 }; 224 225 struct audio_policy_service_ops { 226 /* 227 * Audio output Control functions 228 */ 229 230 /* Opens an audio output with the requested parameters. 231 * 232 * The parameter values can indicate to use the default values in case the 233 * audio policy manager has no specific requirements for the output being 234 * opened. 235 * 236 * When the function returns, the parameter values reflect the actual 237 * values used by the audio hardware output stream. 238 * 239 * The audio policy manager can check if the proposed parameters are 240 * suitable or not and act accordingly. 241 */ 242 audio_io_handle_t (*open_output)(void *service, 243 uint32_t *pDevices, 244 uint32_t *pSamplingRate, 245 uint32_t *pFormat, 246 uint32_t *pChannels, 247 uint32_t *pLatencyMs, 248 audio_policy_output_flags_t flags); 249 250 /* creates a special output that is duplicated to the two outputs passed as 251 * arguments. The duplication is performed by 252 * a special mixer thread in the AudioFlinger. 253 */ 254 audio_io_handle_t (*open_duplicate_output)(void *service, 255 audio_io_handle_t output1, 256 audio_io_handle_t output2); 257 258 /* closes the output stream */ 259 int (*close_output)(void *service, audio_io_handle_t output); 260 261 /* suspends the output. 262 * 263 * When an output is suspended, the corresponding audio hardware output 264 * stream is placed in standby and the AudioTracks attached to the mixer 265 * thread are still processed but the output mix is discarded. 266 */ 267 int (*suspend_output)(void *service, audio_io_handle_t output); 268 269 /* restores a suspended output. */ 270 int (*restore_output)(void *service, audio_io_handle_t output); 271 272 /* */ 273 /* Audio input Control functions */ 274 /* */ 275 276 /* opens an audio input */ 277 audio_io_handle_t (*open_input)(void *service, 278 uint32_t *pDevices, 279 uint32_t *pSamplingRate, 280 uint32_t *pFormat, 281 uint32_t *pChannels, 282 uint32_t acoustics); 283 284 /* closes an audio input */ 285 int (*close_input)(void *service, audio_io_handle_t input); 286 287 /* */ 288 /* misc control functions */ 289 /* */ 290 291 /* set a stream volume for a particular output. 292 * 293 * For the same user setting, a given stream type can have different 294 * volumes for each output (destination device) it is attached to. 295 */ 296 int (*set_stream_volume)(void *service, 297 audio_stream_type_t stream, 298 float volume, 299 audio_io_handle_t output, 300 int delay_ms); 301 302 /* reroute a given stream type to the specified output */ 303 int (*set_stream_output)(void *service, 304 audio_stream_type_t stream, 305 audio_io_handle_t output); 306 307 /* function enabling to send proprietary informations directly from audio 308 * policy manager to audio hardware interface. */ 309 void (*set_parameters)(void *service, 310 audio_io_handle_t io_handle, 311 const char *kv_pairs, 312 int delay_ms); 313 314 /* function enabling to receive proprietary informations directly from 315 * audio hardware interface to audio policy manager. 316 * 317 * Returns a pointer to a heap allocated string. The caller is responsible 318 * for freeing the memory for it. 319 */ 320 321 char * (*get_parameters)(void *service, audio_io_handle_t io_handle, 322 const char *keys); 323 324 /* request the playback of a tone on the specified stream. 325 * used for instance to replace notification sounds when playing over a 326 * telephony device during a phone call. 327 */ 328 int (*start_tone)(void *service, 329 audio_policy_tone_t tone, 330 audio_stream_type_t stream); 331 332 int (*stop_tone)(void *service); 333 334 /* set down link audio volume. */ 335 int (*set_voice_volume)(void *service, 336 float volume, 337 int delay_ms); 338 339 /* move effect to the specified output */ 340 int (*move_effects)(void *service, 341 int session, 342 audio_io_handle_t src_output, 343 audio_io_handle_t dst_output); 344 }; 345 346 /**********************************************************************/ 347 348 /** 349 * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM 350 * and the fields of this data structure must begin with hw_module_t 351 * followed by module specific information. 352 */ 353 typedef struct audio_policy_module { 354 struct hw_module_t common; 355 } audio_policy_module_t; 356 357 struct audio_policy_device { 358 struct hw_device_t common; 359 360 int (*create_audio_policy)(const struct audio_policy_device *device, 361 struct audio_policy_service_ops *aps_ops, 362 void *service, 363 struct audio_policy **ap); 364 365 int (*destroy_audio_policy)(const struct audio_policy_device *device, 366 struct audio_policy *ap); 367 }; 368 369 /** convenience API for opening and closing a supported device */ 370 371 static inline int audio_policy_dev_open(const hw_module_t* module, 372 struct audio_policy_device** device) 373 { 374 return module->methods->open(module, AUDIO_POLICY_INTERFACE, 375 (hw_device_t**)device); 376 } 377 378 static inline int audio_policy_dev_close(struct audio_policy_device* device) 379 { 380 return device->common.close(&device->common); 381 } 382 383 384 __END_DECLS 385 386 #endif // ANDROID_AUDIO_POLICY_INTERFACE_H 387
