1 // Copyright 2016 The Android Open Source Project 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 // 15 16 // Class to manage audio devices in Brillo. 17 18 #ifndef BRILLO_AUDIO_AUDIOSERVICE_BRILLO_AUDIO_MANAGER_H_ 19 #define BRILLO_AUDIO_AUDIOSERVICE_BRILLO_AUDIO_MANAGER_H_ 20 21 #include <sys/cdefs.h> 22 23 #include "brillo_audio_device_info.h" 24 25 __BEGIN_DECLS 26 27 struct BAudioManager; 28 29 typedef struct BAudioManager BAudioManager; 30 31 // Get a pointer to a BAudioManager. This object will refer to the same 32 // underlying client object no matter how many times it is called. 33 // 34 // Returns a pointer to a BAudioManager. Returns NULL on failure. 35 BAudioManager* BAudioManager_new(); 36 37 // Flag to get input devices. 38 static const int GET_DEVICES_INPUTS = 1; 39 // Flag to get output devices. 40 static const int GET_DEVICES_OUTPUTS = 2; 41 42 // Returns the list of input/output devices connected to the system. 43 // 44 // Arg: 45 // brillo_audio_manager: A pointer to a BAudioManager. 46 // flag: Either GET_DEVICES_INPUTS or GET_DEVICES_OUTPUTS. 47 // device_array: An array of BAudioDeviceInfo pointers. The caller has to 48 // allocate this array. 49 // size: The size of device_array. 50 // num_devices: A pointer to an unsigned int which will represent the number 51 // of audio devices connected to the device. 52 // 53 // Returns 0 on success and errno on failure. 54 int BAudioManager_getDevices( 55 const BAudioManager* brillo_audio_manager, int flag, 56 BAudioDeviceInfo* device_array[], unsigned int size, 57 unsigned int* num_devices); 58 59 // Select the input device to be used for recording. 60 // 61 // Arg: 62 // brillo_audio_manager: A pointer to a BAudioManager. 63 // device: Device to set as the input device. Note that the device has to be 64 // an input device. 65 // 66 // Returns 0 on success and errno on failure. 67 int BAudioManager_setInputDevice(const BAudioManager* brillo_audio_manager, 68 const BAudioDeviceInfo* device); 69 70 // Usage types. 71 enum BAudioUsage { 72 kUsageAlarm, 73 kUsageMedia, 74 kUsageNotifications, 75 kUsageSystem, 76 kUsageInvalid 77 }; 78 79 // Select the output device to be used for playback. 80 // 81 // Arg: 82 // brillo_audio_manager: A pointer to a BAudioManager. 83 // device: Device to set as the output device. Note that the device has to 84 // be an output device. 85 // usage: A BAudioUsage type representing a usage to route to |device|. 86 // 87 // Returns 0 on success and errno on failure. 88 int BAudioManager_setOutputDevice( 89 const BAudioManager* brillo_audio_manager, const BAudioDeviceInfo* device, 90 BAudioUsage usage); 91 92 // Get the number of steps for a given stream type. 93 // 94 // Args: 95 // brillo_audio_manager: A pointer to a BAudioManager object. 96 // usage: A BAudioUsage representing the audio stream. 97 // max_steps: A pointer to an int representing the number of steps for a given 98 // usage. 99 // 100 // Returns 0 on success and errno on failure. 101 int BAudioManager_getMaxVolumeSteps(const BAudioManager* brillo_audio_manager, 102 BAudioUsage usage, 103 int* max_steps); 104 105 // Set the number of steps for a given stream type. 106 // 107 // Args: 108 // brillo_audio_manager: A pointer to a BAudioManager object. 109 // usage: A BAudioUsage representing the audio stream. 110 // max_steps: An int representing the number of steps to use for a given 111 // usage. 112 // 113 // Returns 0 on success and errno on failure. 114 int BAudioManager_setMaxVolumeSteps(const BAudioManager* brillo_audio_manager, 115 BAudioUsage usage, 116 int max_steps); 117 118 // Set the volume for a given stream type. 119 // 120 // Args: 121 // brillo_audio_manager: A pointer to a BAudioManager object. 122 // usage: A BAudioUsage representing the audio stream. 123 // device: A pointer to a BAudioDeviceInfo object. 124 // value: An int representing the index to set the volume to. The index must 125 // be less than max_steps if BAudioManager_setMaxVolumeSteps was 126 // called or 100 otherwise. 127 // 128 // Returns 0 on success and errno on failure. 129 int BAudioManager_setVolumeIndex(const BAudioManager* brillo_audio_manager, 130 BAudioUsage usage, 131 const BAudioDeviceInfo* device, 132 int index); 133 134 // Get the volume for a given stream type. 135 // 136 // Args: 137 // brillo_audio_manager: A pointer to a BAudioManager object. 138 // usage: A BAudioUsage representing the audio stream. 139 // device: A pointer to a BAudioDeviceInfo object. 140 // value: A pointer to int. This will be set to an int representing the volume 141 // index for |usage|. 142 // 143 // Returns 0 on success and errno on failure. 144 int BAudioManager_getVolumeIndex(const BAudioManager* brillo_audio_manager, 145 BAudioUsage usage, 146 const BAudioDeviceInfo* device, 147 int* index); 148 149 // Get the default stream for volume buttons. If 150 // BAudioManager_setVolumeControlUsage has not been called, this will return 151 // kInvalidUsage. 152 // 153 // Args: 154 // brillo_audio_manager: A pointer to a BAudioManager object. 155 // usage: A pointer to a BAudioUsage representing the audio stream. 156 // 157 // Returns 0 on success and errno on failure. 158 int BAudioManager_getVolumeControlUsage( 159 const BAudioManager* brillo_audio_manager, BAudioUsage* usage); 160 161 // Set the default stream to use for volume buttons. By default, streams will be 162 // ordered by priority: 163 // 1. kUsageAlarm 164 // 2. kUsageNotifications 165 // 3. kUsageSystem 166 // 4. kUsageMedia 167 // 168 // Calling BAudioMananager_setVolumeControlUsage with kInvalidUsage will reset 169 // the volume control stream to its default priorities and undo the effects of 170 // previous calls to BAudioManager_setVolumeControlUsage. 171 // 172 // Args: 173 // brillo_audio_manager: A pointer to a BAudioManager object. 174 // usage: A BAudioUsage representing the audio stream. 175 // 176 // Returns 0 on success and errno on failure. 177 int BAudioManager_setVolumeControlUsage( 178 const BAudioManager* brillo_audio_manager, BAudioUsage usage); 179 180 // Increment the volume of active streams or stream selected using 181 // BAudioManager_setVolumeControlUsage. 182 // 183 // Args: 184 // brillo_audio_manager: A pointer to a BAudioManager object. 185 // 186 // Returns 0 on success and errno on failure. 187 int BAudioManager_incrementVolume(const BAudioManager* brillo_audio_manager); 188 189 // Decrement the volume of active streams or stream selected using 190 // BAudioManager_setVolumeControlUsage. 191 // 192 // Args: 193 // brillo_audio_manager: A pointer to a BAudioManager object. 194 // 195 // Returns 0 on success and errno on failure. 196 int BAudioManager_decrementVolume(const BAudioManager* brillo_audio_manager); 197 198 // Object used for callbacks. 199 struct BAudioCallback { 200 // Function to be called when an audio device is added. If multiple audio 201 // devices are added, then this function will be called multiple times. The 202 // user is not responsible for freeing added_device. 203 void (*OnAudioDeviceAdded)(const BAudioDeviceInfo* added_device, 204 void* user_data); 205 206 // Function to be called when an audio device is removed. If multiple audio 207 // devices are removed, then this function will be called multiple times. The 208 // user is not responsible for freeing removed_device. 209 void (*OnAudioDeviceRemoved)(const BAudioDeviceInfo* removed_device, 210 void* user_data); 211 212 // Function to be called when the volume button is pressed. 213 void (*OnVolumeChanged)(BAudioUsage usage, 214 int old_volume_index, 215 int new_volume_index, 216 void* user_data); 217 }; 218 219 typedef struct BAudioCallback BAudioCallback; 220 221 // Registers a callback object that lets clients know when audio devices have 222 // been added/removed from the system. 223 // 224 // Arg: 225 // brillo_audio_manager: A pointer to a BAudioManager. 226 // callback: An object of type BAudioCallback. The BAudioManager 227 // maintains ownership of this object. 228 // user_data : A pointer to user data. This is not used by BAudioManager and 229 // is passed as an arg to callbacks. 230 // callback_id: A pointer to an int. The int represents a token that can be 231 // used to de-register this callback. Contains 0 on failure. 232 // 233 // Returns 0 on success and errno on failure. 234 int BAudioManager_registerAudioCallback( 235 const BAudioManager* brillo_audio_manager, const BAudioCallback* callback, 236 void* user_data, int* callback_id); 237 238 // Unregisters a callback object. 239 // 240 // Arg: 241 // brillo_audio_manager: A pointer to a BAudioManager. 242 // callback_id: A token correspoding to the callback object. 243 // 244 // Returns 0 on success and errno on failure. 245 int BAudioManager_unregisterAudioCallback( 246 const BAudioManager* brillo_audio_manager, int callback_id); 247 248 // Free a Brillo audio manager object. 249 // 250 // Arg: 251 // brillo_audio_manager: A pointer to a BAudioManager to be freed. 252 // 253 // Returns 0 on success and errno on failure. 254 int BAudioManager_delete(BAudioManager* brillo_audio_manager); 255 256 __END_DECLS 257 258 #endif // BRILLO_AUDIO_AUDIOSERVICE_BRILLO_AUDIO_MANAGER_H_ 259
