1 /* 2 * Copyright (C) 2009 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 #ifndef ANDROID_AUDIOPOLICYINTERFACE_H 18 #define ANDROID_AUDIOPOLICYINTERFACE_H 19 20 #include <media/AudioSystem.h> 21 #include <media/ToneGenerator.h> 22 #include <utils/String8.h> 23 24 #include <hardware_legacy/AudioSystemLegacy.h> 25 #include <hardware/audio_policy.h> 26 27 namespace android_audio_legacy { 28 using android::Vector; 29 using android::String8; 30 using android::ToneGenerator; 31 32 // ---------------------------------------------------------------------------- 33 34 // The AudioPolicyInterface and AudioPolicyClientInterface classes define the communication interfaces 35 // between the platform specific audio policy manager and Android generic audio policy manager. 36 // The platform specific audio policy manager must implement methods of the AudioPolicyInterface class. 37 // This implementation makes use of the AudioPolicyClientInterface to control the activity and 38 // configuration of audio input and output streams. 39 // 40 // The platform specific audio policy manager is in charge of the audio routing and volume control 41 // policies for a given platform. 42 // The main roles of this module are: 43 // - keep track of current system state (removable device connections, phone state, user requests...). 44 // System state changes and user actions are notified to audio policy manager with methods of the AudioPolicyInterface. 45 // - process getOutput() queries received when AudioTrack objects are created: Those queries 46 // return a handler on an output that has been selected, configured and opened by the audio policy manager and that 47 // must be used by the AudioTrack when registering to the AudioFlinger with the createTrack() method. 48 // When the AudioTrack object is released, a putOutput() query is received and the audio policy manager can decide 49 // to close or reconfigure the output depending on other streams using this output and current system state. 50 // - similarly process getInput() and putInput() queries received from AudioRecord objects and configure audio inputs. 51 // - process volume control requests: the stream volume is converted from an index value (received from UI) to a float value 52 // applicable to each output as a function of platform specific settings and current output route (destination device). It 53 // also make sure that streams are not muted if not allowed (e.g. camera shutter sound in some countries). 54 // 55 // The platform specific audio policy manager is provided as a shared library by platform vendors (as for libaudio.so) 56 // and is linked with libaudioflinger.so 57 58 59 // Audio Policy Manager Interface 60 class AudioPolicyInterface 61 { 62 63 public: ~AudioPolicyInterface()64 virtual ~AudioPolicyInterface() {} 65 // 66 // configuration functions 67 // 68 69 // indicate a change in device connection status 70 virtual status_t setDeviceConnectionState(audio_devices_t device, 71 AudioSystem::device_connection_state state, 72 const char *device_address) = 0; 73 // retrieve a device connection status 74 virtual AudioSystem::device_connection_state getDeviceConnectionState(audio_devices_t device, 75 const char *device_address) = 0; 76 // indicate a change in phone state. Valid phones states are defined by AudioSystem::audio_mode 77 virtual void setPhoneState(int state) = 0; 78 // force using a specific device category for the specified usage 79 virtual void setForceUse(AudioSystem::force_use usage, AudioSystem::forced_config config) = 0; 80 // retrieve current device category forced for a given usage 81 virtual AudioSystem::forced_config getForceUse(AudioSystem::force_use usage) = 0; 82 // set a system property (e.g. camera sound always audible) 83 virtual void setSystemProperty(const char* property, const char* value) = 0; 84 // check proper initialization 85 virtual status_t initCheck() = 0; 86 87 // 88 // Audio routing query functions 89 // 90 91 // request an output appropriate for playback of the supplied stream type and parameters 92 virtual audio_io_handle_t getOutput(AudioSystem::stream_type stream, 93 uint32_t samplingRate, 94 audio_format_t format, 95 audio_channel_mask_t channelMask, 96 AudioSystem::output_flags flags, 97 const audio_offload_info_t *offloadInfo) = 0; 98 // indicates to the audio policy manager that the output starts being used by corresponding stream. 99 virtual status_t startOutput(audio_io_handle_t output, 100 AudioSystem::stream_type stream, 101 int session = 0) = 0; 102 // indicates to the audio policy manager that the output stops being used by corresponding stream. 103 virtual status_t stopOutput(audio_io_handle_t output, 104 AudioSystem::stream_type stream, 105 int session = 0) = 0; 106 // releases the output. 107 virtual void releaseOutput(audio_io_handle_t output) = 0; 108 109 // request an input appropriate for record from the supplied device with supplied parameters. 110 virtual audio_io_handle_t getInput(int inputSource, 111 uint32_t samplingRate, 112 audio_format_t format, 113 audio_channel_mask_t channelMask, 114 AudioSystem::audio_in_acoustics acoustics) = 0; 115 // indicates to the audio policy manager that the input starts being used. 116 virtual status_t startInput(audio_io_handle_t input) = 0; 117 // indicates to the audio policy manager that the input stops being used. 118 virtual status_t stopInput(audio_io_handle_t input) = 0; 119 // releases the input. 120 virtual void releaseInput(audio_io_handle_t input) = 0; 121 122 // 123 // volume control functions 124 // 125 126 // initialises stream volume conversion parameters by specifying volume index range. 127 virtual void initStreamVolume(AudioSystem::stream_type stream, 128 int indexMin, 129 int indexMax) = 0; 130 131 // sets the new stream volume at a level corresponding to the supplied index for the 132 // supplied device. By convention, specifying AUDIO_DEVICE_OUT_DEFAULT means 133 // setting volume for all devices 134 virtual status_t setStreamVolumeIndex(AudioSystem::stream_type stream, 135 int index, 136 audio_devices_t device) = 0; 137 138 // retrieve current volume index for the specified stream and the 139 // specified device. By convention, specifying AUDIO_DEVICE_OUT_DEFAULT means 140 // querying the volume of the active device. 141 virtual status_t getStreamVolumeIndex(AudioSystem::stream_type stream, 142 int *index, 143 audio_devices_t device) = 0; 144 145 // return the strategy corresponding to a given stream type 146 virtual uint32_t getStrategyForStream(AudioSystem::stream_type stream) = 0; 147 148 // return the enabled output devices for the given stream type 149 virtual audio_devices_t getDevicesForStream(AudioSystem::stream_type stream) = 0; 150 151 // Audio effect management 152 virtual audio_io_handle_t getOutputForEffect(const effect_descriptor_t *desc) = 0; 153 virtual status_t registerEffect(const effect_descriptor_t *desc, 154 audio_io_handle_t io, 155 uint32_t strategy, 156 int session, 157 int id) = 0; 158 virtual status_t unregisterEffect(int id) = 0; 159 virtual status_t setEffectEnabled(int id, bool enabled) = 0; 160 161 virtual bool isStreamActive(int stream, uint32_t inPastMs = 0) const = 0; 162 virtual bool isStreamActiveRemotely(int stream, uint32_t inPastMs = 0) const = 0; 163 virtual bool isSourceActive(audio_source_t source) const = 0; 164 165 //dump state 166 virtual status_t dump(int fd) = 0; 167 168 virtual bool isOffloadSupported(const audio_offload_info_t& offloadInfo) = 0; 169 }; 170 171 172 // Audio Policy client Interface 173 class AudioPolicyClientInterface 174 { 175 public: ~AudioPolicyClientInterface()176 virtual ~AudioPolicyClientInterface() {} 177 178 // 179 // Audio HW module functions 180 // 181 182 // loads a HW module. 183 virtual audio_module_handle_t loadHwModule(const char *name) = 0; 184 185 // 186 // Audio output Control functions 187 // 188 189 // opens an audio output with the requested parameters. The parameter values can indicate to use the default values 190 // in case the audio policy manager has no specific requirements for the output being opened. 191 // When the function returns, the parameter values reflect the actual values used by the audio hardware output stream. 192 // The audio policy manager can check if the proposed parameters are suitable or not and act accordingly. 193 virtual audio_io_handle_t openOutput(audio_module_handle_t module, 194 audio_devices_t *pDevices, 195 uint32_t *pSamplingRate, 196 audio_format_t *pFormat, 197 audio_channel_mask_t *pChannelMask, 198 uint32_t *pLatencyMs, 199 audio_output_flags_t flags, 200 const audio_offload_info_t *offloadInfo = NULL) = 0; 201 // creates a special output that is duplicated to the two outputs passed as arguments. The duplication is performed by 202 // a special mixer thread in the AudioFlinger. 203 virtual audio_io_handle_t openDuplicateOutput(audio_io_handle_t output1, audio_io_handle_t output2) = 0; 204 // closes the output stream 205 virtual status_t closeOutput(audio_io_handle_t output) = 0; 206 // suspends the output. When an output is suspended, the corresponding audio hardware output stream is placed in 207 // standby and the AudioTracks attached to the mixer thread are still processed but the output mix is discarded. 208 virtual status_t suspendOutput(audio_io_handle_t output) = 0; 209 // restores a suspended output. 210 virtual status_t restoreOutput(audio_io_handle_t output) = 0; 211 212 // 213 // Audio input Control functions 214 // 215 216 // opens an audio input 217 virtual audio_io_handle_t openInput(audio_module_handle_t module, 218 audio_devices_t *pDevices, 219 uint32_t *pSamplingRate, 220 audio_format_t *pFormat, 221 audio_channel_mask_t *pChannelMask) = 0; 222 // closes an audio input 223 virtual status_t closeInput(audio_io_handle_t input) = 0; 224 // 225 // misc control functions 226 // 227 228 // set a stream volume for a particular output. For the same user setting, a given stream type can have different volumes 229 // for each output (destination device) it is attached to. 230 virtual status_t setStreamVolume(AudioSystem::stream_type stream, float volume, audio_io_handle_t output, int delayMs = 0) = 0; 231 232 // invalidate a stream type, causing a reroute to an unspecified new output 233 virtual status_t invalidateStream(AudioSystem::stream_type stream) = 0; 234 235 // function enabling to send proprietary informations directly from audio policy manager to audio hardware interface. 236 virtual void setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs, int delayMs = 0) = 0; 237 // function enabling to receive proprietary informations directly from audio hardware interface to audio policy manager. 238 virtual String8 getParameters(audio_io_handle_t ioHandle, const String8& keys) = 0; 239 240 // request the playback of a tone on the specified stream: used for instance to replace notification sounds when playing 241 // over a telephony device during a phone call. 242 virtual status_t startTone(ToneGenerator::tone_type tone, AudioSystem::stream_type stream) = 0; 243 virtual status_t stopTone() = 0; 244 245 // set down link audio volume. 246 virtual status_t setVoiceVolume(float volume, int delayMs = 0) = 0; 247 248 // move effect to the specified output 249 virtual status_t moveEffects(int session, 250 audio_io_handle_t srcOutput, 251 audio_io_handle_t dstOutput) = 0; 252 253 }; 254 255 extern "C" AudioPolicyInterface* createAudioPolicyManager(AudioPolicyClientInterface *clientInterface); 256 extern "C" void destroyAudioPolicyManager(AudioPolicyInterface *interface); 257 258 259 }; // namespace android 260 261 #endif // ANDROID_AUDIOPOLICYINTERFACE_H 262