/* * Copyright (C) 2009 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef ANDROID_AUDIOPOLICY_INTERFACE_H #define ANDROID_AUDIOPOLICY_INTERFACE_H #include #include #include namespace android { // ---------------------------------------------------------------------------- // The AudioPolicyInterface and AudioPolicyClientInterface classes define the communication interfaces // between the platform specific audio policy manager and Android generic audio policy manager. // The platform specific audio policy manager must implement methods of the AudioPolicyInterface class. // This implementation makes use of the AudioPolicyClientInterface to control the activity and // configuration of audio input and output streams. // // The platform specific audio policy manager is in charge of the audio routing and volume control // policies for a given platform. // The main roles of this module are: // - keep track of current system state (removable device connections, phone state, user requests...). // System state changes and user actions are notified to audio policy manager with methods of the AudioPolicyInterface. // - process getOutput() queries received when AudioTrack objects are created: Those queries // return a handler on an output that has been selected, configured and opened by the audio policy manager and that // must be used by the AudioTrack when registering to the AudioFlinger with the createTrack() method. // When the AudioTrack object is released, a putOutput() query is received and the audio policy manager can decide // to close or reconfigure the output depending on other streams using this output and current system state. // - similarly process getInput() and putInput() queries received from AudioRecord objects and configure audio inputs. // - process volume control requests: the stream volume is converted from an index value (received from UI) to a float value // applicable to each output as a function of platform specific settings and current output route (destination device). It // also make sure that streams are not muted if not allowed (e.g. camera shutter sound in some countries). // // The platform specific audio policy manager is provided as a shared library by platform vendors (as for libaudio.so) // and is linked with libaudioflinger.so // Audio Policy Manager Interface class AudioPolicyInterface { public: virtual ~AudioPolicyInterface() {} // // configuration functions // // indicate a change in device connection status virtual status_t setDeviceConnectionState(audio_devices_t device, audio_policy_dev_state_t state, const char *device_address) = 0; // retrieve a device connection status virtual audio_policy_dev_state_t getDeviceConnectionState(audio_devices_t device, const char *device_address) = 0; // indicate a change in phone state. Valid phones states are defined by audio_mode_t virtual void setPhoneState(audio_mode_t state) = 0; // force using a specific device category for the specified usage virtual void setForceUse(audio_policy_force_use_t usage, audio_policy_forced_cfg_t config) = 0; // retrieve current device category forced for a given usage virtual audio_policy_forced_cfg_t getForceUse(audio_policy_force_use_t usage) = 0; // set a system property (e.g. camera sound always audible) virtual void setSystemProperty(const char* property, const char* value) = 0; // check proper initialization virtual status_t initCheck() = 0; // // Audio routing query functions // // request an output appropriate for playback of the supplied stream type and parameters virtual audio_io_handle_t getOutput(audio_stream_type_t stream, uint32_t samplingRate, audio_format_t format, audio_channel_mask_t channelMask, audio_output_flags_t flags, const audio_offload_info_t *offloadInfo) = 0; // indicates to the audio policy manager that the output starts being used by corresponding stream. virtual status_t startOutput(audio_io_handle_t output, audio_stream_type_t stream, int session = 0) = 0; // indicates to the audio policy manager that the output stops being used by corresponding stream. virtual status_t stopOutput(audio_io_handle_t output, audio_stream_type_t stream, int session = 0) = 0; // releases the output. virtual void releaseOutput(audio_io_handle_t output) = 0; // request an input appropriate for record from the supplied device with supplied parameters. virtual audio_io_handle_t getInput(audio_source_t inputSource, uint32_t samplingRate, audio_format_t format, audio_channel_mask_t channelMask, audio_in_acoustics_t acoustics) = 0; // indicates to the audio policy manager that the input starts being used. virtual status_t startInput(audio_io_handle_t input) = 0; // indicates to the audio policy manager that the input stops being used. virtual status_t stopInput(audio_io_handle_t input) = 0; // releases the input. virtual void releaseInput(audio_io_handle_t input) = 0; // // volume control functions // // initialises stream volume conversion parameters by specifying volume index range. virtual void initStreamVolume(audio_stream_type_t stream, int indexMin, int indexMax) = 0; // sets the new stream volume at a level corresponding to the supplied index for the // supplied device. By convention, specifying AUDIO_DEVICE_OUT_DEFAULT means // setting volume for all devices virtual status_t setStreamVolumeIndex(audio_stream_type_t stream, int index, audio_devices_t device) = 0; // retrieve current volume index for the specified stream and the // specified device. By convention, specifying AUDIO_DEVICE_OUT_DEFAULT means // querying the volume of the active device. virtual status_t getStreamVolumeIndex(audio_stream_type_t stream, int *index, audio_devices_t device) = 0; // return the strategy corresponding to a given stream type virtual uint32_t getStrategyForStream(audio_stream_type_t stream) = 0; // return the enabled output devices for the given stream type virtual audio_devices_t getDevicesForStream(audio_stream_type_t stream) = 0; // Audio effect management virtual audio_io_handle_t getOutputForEffect(const effect_descriptor_t *desc) = 0; virtual status_t registerEffect(const effect_descriptor_t *desc, audio_io_handle_t io, uint32_t strategy, int session, int id) = 0; virtual status_t unregisterEffect(int id) = 0; virtual status_t setEffectEnabled(int id, bool enabled) = 0; virtual bool isStreamActive(audio_stream_type_t stream, uint32_t inPastMs = 0) const = 0; virtual bool isStreamActiveRemotely(audio_stream_type_t stream, uint32_t inPastMs = 0) const = 0; virtual bool isSourceActive(audio_source_t source) const = 0; //dump state virtual status_t dump(int fd) = 0; virtual bool isOffloadSupported(const audio_offload_info_t& offloadInfo) = 0; }; // Audio Policy client Interface class AudioPolicyClientInterface { public: virtual ~AudioPolicyClientInterface() {} // // Audio HW module functions // // loads a HW module. virtual audio_module_handle_t loadHwModule(const char *name) = 0; // // Audio output Control functions // // opens an audio output with the requested parameters. The parameter values can indicate to use the default values // in case the audio policy manager has no specific requirements for the output being opened. // When the function returns, the parameter values reflect the actual values used by the audio hardware output stream. // The audio policy manager can check if the proposed parameters are suitable or not and act accordingly. virtual audio_io_handle_t openOutput(audio_module_handle_t module, audio_devices_t *pDevices, uint32_t *pSamplingRate, audio_format_t *pFormat, audio_channel_mask_t *pChannelMask, uint32_t *pLatencyMs, audio_output_flags_t flags, const audio_offload_info_t *offloadInfo = NULL) = 0; // creates a special output that is duplicated to the two outputs passed as arguments. The duplication is performed by // a special mixer thread in the AudioFlinger. virtual audio_io_handle_t openDuplicateOutput(audio_io_handle_t output1, audio_io_handle_t output2) = 0; // closes the output stream virtual status_t closeOutput(audio_io_handle_t output) = 0; // suspends the output. When an output is suspended, the corresponding audio hardware output stream is placed in // standby and the AudioTracks attached to the mixer thread are still processed but the output mix is discarded. virtual status_t suspendOutput(audio_io_handle_t output) = 0; // restores a suspended output. virtual status_t restoreOutput(audio_io_handle_t output) = 0; // // Audio input Control functions // // opens an audio input virtual audio_io_handle_t openInput(audio_module_handle_t module, audio_devices_t *pDevices, uint32_t *pSamplingRate, audio_format_t *pFormat, audio_channel_mask_t *pChannelMask) = 0; // closes an audio input virtual status_t closeInput(audio_io_handle_t input) = 0; // // misc control functions // // set a stream volume for a particular output. For the same user setting, a given stream type can have different volumes // for each output (destination device) it is attached to. virtual status_t setStreamVolume(audio_stream_type_t stream, float volume, audio_io_handle_t output, int delayMs = 0) = 0; // invalidate a stream type, causing a reroute to an unspecified new output virtual status_t invalidateStream(audio_stream_type_t stream) = 0; // function enabling to send proprietary informations directly from audio policy manager to audio hardware interface. virtual void setParameters(audio_io_handle_t ioHandle, const String8& keyValuePairs, int delayMs = 0) = 0; // function enabling to receive proprietary informations directly from audio hardware interface to audio policy manager. virtual String8 getParameters(audio_io_handle_t ioHandle, const String8& keys) = 0; // request the playback of a tone on the specified stream: used for instance to replace notification sounds when playing // over a telephony device during a phone call. virtual status_t startTone(audio_policy_tone_t tone, audio_stream_type_t stream) = 0; virtual status_t stopTone() = 0; // set down link audio volume. virtual status_t setVoiceVolume(float volume, int delayMs = 0) = 0; // move effect to the specified output virtual status_t moveEffects(int session, audio_io_handle_t srcOutput, audio_io_handle_t dstOutput) = 0; }; extern "C" AudioPolicyInterface* createAudioPolicyManager(AudioPolicyClientInterface *clientInterface); extern "C" void destroyAudioPolicyManager(AudioPolicyInterface *interface); }; // namespace android #endif // ANDROID_AUDIOPOLICY_INTERFACE_H