[Android Software Development] ilatimer1:
Here is the default audio_policy.conf

# Global configuration section: lists input and output devices always present on the device

# as well as the output device selected by default.

# Devices are designated by a string that corresponds to the enum in audio.h

global_configuration {

attached_output_devices AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_TELEPHONY_TX

default_output_device AUDIO_DEVICE_OUT_SPEAKER

attached_input_devices AUDIO_DEVICE_IN_BUILTIN_MIC|AUDIO_DEVICE_IN_BACK_MIC|AUDIO_DEVICE_IN_REMOTE_SUBMIX|AUDIO_DEVICE_IN_VOICE_CALL|AUDIO_DEVICE_IN_TELEPHONY_RX|AUDIO_DEVICE_IN_FM_TUNER

}

# audio hardware module section: contains descriptors for all audio hw modules present on the

# device. Each hw module node is named after the corresponding hw module library base name.

# For instance, "primary" corresponds to audio.primary.<device>.so.

# The "primary" module is mandatory and must include at least one output with

# AUDIO_OUTPUT_FLAG_PRIMARY flag.

# Each module descriptor contains one or more output profile descriptors and zero or more

# input profile descriptors. Each profile lists all the parameters supported by a given output

# or input stream category.

# The "channel_masks", "formats", "devices" and "flags" are specified using strings corresponding

# to enums in audio.h and audio_policy.h. They are concatenated by use of "|" without space or "\n".

audio_hw_modules {

primary {

outputs {

primary {

sampling_rates 44100|48000

channel_masks AUDIO_CHANNEL_OUT_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL|AUDIO_DEVICE_OUT_PROXY|AUDIO_DEVICE_OUT_FM

flags AUDIO_OUTPUT_FLAG_FAST|AUDIO_OUTPUT_FLAG_PRIMARY

}

raw {

sampling_rates 48000

channel_masks AUDIO_CHANNEL_OUT_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL

flags AUDIO_OUTPUT_FLAG_FAST|AUDIO_OUTPUT_FLAG_RAW

}

deep_buffer {

sampling_rates 44100|48000

channel_masks AUDIO_CHANNEL_OUT_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL|AUDIO_DEVICE_OUT_PROXY|AUDIO_DEVICE_OUT_FM

flags AUDIO_OUTPUT_FLAG_DEEP_BUFFER

}

multichannel {

sampling_rates 8000|11025|16000|22050|32000|44100|48000|64000|88200|96000|128000|176400|192000

channel_masks dynamic

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_AUX_DIGITAL|AUDIO_DEVICE_OUT_PROXY

flags AUDIO_OUTPUT_FLAG_DIRECT

}

direct_pcm {

sampling_rates 44100|48000|64000|88200|96000|176400|192000

channel_masks AUDIO_CHANNEL_OUT_MONO|AUDIO_CHANNEL_OUT_STEREO|AUDIO_CHANNEL_OUT_2POINT1|AUDIO_CHANNEL_OUT_QUAD|AUDIO_CHANNEL_OUT_PENTA|AUDIO_CHANNEL_OUT_5POINT1|AUDIO_CHANNEL_OUT_6POINT1|AUDIO_CHANNEL_OUT_7POINT1

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO

flags AUDIO_OUTPUT_FLAG_DIRECT|AUDIO_OUTPUT_FLAG_DIRECT_PCM

}

compress_offload {

sampling_rates 8000|11025|12000|16000|22050|24000|32000|44100|48000|64000|88200|96000|176400|192000

channel_masks AUDIO_CHANNEL_OUT_MONO|AUDIO_CHANNEL_OUT_STEREO|AUDIO_CHANNEL_OUT_2POINT1|AUDIO_CHANNEL_OUT_QUAD|AUDIO_CHANNEL_OUT_PENTA|AUDIO_CHANNEL_OUT_5POINT1|AUDIO_CHANNEL_OUT_6POINT1|AUDIO_CHANNEL_OUT_7POINT1

#ifndef VENDOR_EDIT

#lifei@OnePlus.MultiMediaService, 2015/12/23,add MP2 offload playback

#formats AUDIO_FORMAT_MP3|AUDIO_FORMAT_PCM_16_BIT_OFFLOAD|AUDIO_FORMAT_PCM_24_BIT_OFFLOAD|AUDIO_FORMAT_FLAC|AUDIO_FORMAT_ALAC|AUDIO_FORMAT_APE|AUDIO_FORMAT_AAC_LC|AUDIO_FORMAT_AAC_HE_V1|AUDIO_FORMAT_AAC_HE_V2|AUDIO_FORMAT_WMA|AUDIO_FORMAT_WMA_PRO|AUDIO_FORMAT_VORBIS|AUDIO_FORMAT_AAC_ADTS_LC|AUDIO_FORMAT_AAC_ADTS_HE_V1|AUDIO_FORMAT_AAC_ADTS_HE_V2

#else

formats AUDIO_FORMAT_MP3|AUDIO_FORMAT_PCM_16_BIT_OFFLOAD|AUDIO_FORMAT_PCM_24_BIT_OFFLOAD|AUDIO_FORMAT_FLAC|AUDIO_FORMAT_ALAC|AUDIO_FORMAT_APE|AUDIO_FORMAT_AAC_LC|AUDIO_FORMAT_AAC_HE_V1|AUDIO_FORMAT_AAC_HE_V2|AUDIO_FORMAT_WMA|AUDIO_FORMAT_WMA_PRO|AUDIO_FORMAT_VORBIS|AUDIO_FORMAT_AAC_ADTS_LC|AUDIO_FORMAT_AAC_ADTS_HE_V1|AUDIO_FORMAT_AAC_ADTS_HE_V2|AUDIO_FORMAT_MP2

#endif/*VENDOR_EDIT*/

devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO|AUDIO_DEVICE_OUT_AUX_DIGITAL|AUDIO_DEVICE_OUT_PROXY

flags AUDIO_OUTPUT_FLAG_DIRECT|AUDIO_OUTPUT_FLAG_COMPRESS_OFFLOAD|AUDIO_OUTPUT_FLAG_NON_BLOCKING

}

incall_music {

sampling_rates 8000|16000|48000

channel_masks AUDIO_CHANNEL_OUT_MONO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO

flags AUDIO_OUTPUT_FLAG_DIRECT|AUDIO_OUTPUT_FLAG_INCALL_MUSIC

}

voice_tx {

sampling_rates 8000|16000|48000

channel_masks AUDIO_CHANNEL_OUT_STEREO|AUDIO_CHANNEL_OUT_MONO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_TELEPHONY_TX

}

voip_rx {

sampling_rates 8000|16000

channel_masks AUDIO_CHANNEL_OUT_MONO

formats AUDIO_FORMAT_PCM_16_BIT|AUDIO_FORMAT_AMR_NB|AUDIO_FORMAT_AMR_WB|AUDIO_FORMAT_QCELP|AUDIO_FORMAT_EVRC|AUDIO_FORMAT_EVRCB|AUDIO_FORMAT_EVRCWB|AUDIO_FORMAT_EVRCNW

devices AUDIO_DEVICE_OUT_SPEAKER|AUDIO_DEVICE_OUT_EARPIECE|AUDIO_DEVICE_OUT_WIRED_HEADSET|AUDIO_DEVICE_OUT_WIRED_HEADPHONE|AUDIO_DEVICE_OUT_LINE|AUDIO_DEVICE_OUT_ALL_SCO

flags AUDIO_OUTPUT_FLAG_DIRECT|AUDIO_OUTPUT_FLAG_VOIP_RX

}

}

inputs {

primary {

sampling_rates 8000|11025|12000|16000|22050|24000|32000|44100|48000

channel_masks AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO|AUDIO_CHANNEL_IN_FRONT_BACK

formats AUDIO_FORMAT_PCM_16_BIT|AUDIO_FORMAT_AMR_NB|AUDIO_FORMAT_AMR_WB|AUDIO_FORMAT_QCELP|AUDIO_FORMAT_EVRC|AUDIO_FORMAT_EVRCB|AUDIO_FORMAT_EVRCWB|AUDIO_FORMAT_EVRCNW

devices AUDIO_DEVICE_IN_WIRED_HEADSET|AUDIO_DEVICE_IN_BLUETOOTH_SCO_HEADSET|AUDIO_DEVICE_IN_FM_TUNER|AUDIO_DEVICE_IN_VOICE_CALL

}

surround_sound {

sampling_rates 8000|11025|12000|16000|22050|24000|32000|44100|48000

channel_masks AUDIO_CHANNEL_IN_5POINT1|AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO|AUDIO_CHANNEL_IN_FRONT_BACK

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_IN_BUILTIN_MIC|AUDIO_DEVICE_IN_BACK_MIC

}

voice_rx {

sampling_rates 8000|16000|48000

channel_masks AUDIO_CHANNEL_IN_STEREO|AUDIO_CHANNEL_IN_MONO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_IN_TELEPHONY_RX

}

}

}

a2dp {

outputs {

a2dp {

sampling_rates 44100

channel_masks AUDIO_CHANNEL_OUT_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_ALL_A2DP

}

}

inputs {

a2dp {

sampling_rates 44100|48000

channel_masks AUDIO_CHANNEL_IN_MONO|AUDIO_CHANNEL_IN_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_IN_BLUETOOTH_A2DP

}

}

}

usb {

outputs {

usb_accessory {

sampling_rates 44100

channel_masks AUDIO_CHANNEL_OUT_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_USB_ACCESSORY

}

usb_device {

sampling_rates dynamic

channel_masks dynamic

formats dynamic

devices AUDIO_DEVICE_OUT_USB_DEVICE

}

}

inputs {

usb_device {

sampling_rates dynamic

channel_masks dynamic

formats dynamic

devices AUDIO_DEVICE_IN_USB_DEVICE

}

}

}

r_submix {

outputs {

submix {

sampling_rates 48000

channel_masks AUDIO_CHANNEL_OUT_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_OUT_REMOTE_SUBMIX

}

}

inputs {

submix {

sampling_rates 48000

channel_masks AUDIO_CHANNEL_IN_STEREO

formats AUDIO_FORMAT_PCM_16_BIT

devices AUDIO_DEVICE_IN_REMOTE_SUBMIX

}

}

}

}