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Audio Codec

Overview

The Audio Codec API provides access to digital audio codecs.

Configuration Options

Related configuration options:

API Reference

group audio_codec_interface

Abstraction for audio codecs.

Enums

enum audio_pcm_rate_t

PCM audio sample rates

Values:

AUDIO_PCM_RATE_8K = 8000
AUDIO_PCM_RATE_16K = 16000
AUDIO_PCM_RATE_24K = 24000
AUDIO_PCM_RATE_32K = 32000
AUDIO_PCM_RATE_44P1K = 44100
AUDIO_PCM_RATE_48K = 48000
AUDIO_PCM_RATE_96K = 96000
AUDIO_PCM_RATE_192K = 192000
enum audio_pcm_width_t

PCM audio sample bit widths

Values:

AUDIO_PCM_WIDTH_16_BITS = 16
AUDIO_PCM_WIDTH_20_BITS = 20
AUDIO_PCM_WIDTH_24_BITS = 24
AUDIO_PCM_WIDTH_32_BITS = 32
enum audio_dai_type_t

Digital Audio Interface (DAI) type

Values:

AUDIO_DAI_TYPE_I2S
AUDIO_DAI_TYPE_INVALID
enum audio_property_t

Codec properties that can be set by audio_codec_set_property()

Values:

AUDIO_PROPERTY_OUTPUT_VOLUME
AUDIO_PROPERTY_OUTPUT_MUTE
enum audio_channel_t

Audio channel identifiers to use in audio_codec_set_property()

Values:

AUDIO_CHANNEL_FRONT_LEFT
AUDIO_CHANNEL_FRONT_RIGHT
AUDIO_CHANNEL_LFE
AUDIO_CHANNEL_FRONT_CENTER
AUDIO_CHANNEL_REAR_LEFT
AUDIO_CHANNEL_REAR_RIGHT
AUDIO_CHANNEL_REAR_CENTER
AUDIO_CHANNEL_SIDE_LEFT
AUDIO_CHANNEL_SIDE_RIGHT
AUDIO_CHANNEL_ALL

Functions

static int audio_codec_configure(struct device *dev, struct audio_codec_cfg *cfg)

Configure the audio codec.

Configure the audio codec device according to the configuration parameters provided as input

Return

0 on success, negative error code on failure

Parameters
  • dev: Pointer to the device structure for codec driver instance.

  • cfg: Pointer to the structure containing the codec configuration.

static void audio_codec_start_output(struct device *dev)

Set codec to start output audio playback.

Setup the audio codec device to start the audio playback

Return

none

Parameters
  • dev: Pointer to the device structure for codec driver instance.

static void audio_codec_stop_output(struct device *dev)

Set codec to stop output audio playback.

Setup the audio codec device to stop the audio playback

Return

none

Parameters
  • dev: Pointer to the device structure for codec driver instance.

static int audio_codec_set_property(struct device *dev, audio_property_t property, audio_channel_t channel, audio_property_value_t val)

Set a codec property defined by audio_property_t.

Set a property such as volume level, clock configuration etc.

Return

0 on success, negative error code on failure

Parameters
  • dev: Pointer to the device structure for codec driver instance.

  • property: The codec property to set

  • channel: The audio channel for which the property has to be set

  • val: pointer to a property value of type audio_codec_property_value_t

static int audio_codec_apply_properties(struct device *dev)

Atomically apply any cached properties.

Following one or more invocations of audio_codec_set_property, that may have been cached by the driver, audio_codec_apply_properties can be invoked to apply all the properties as atomic as possible

Return

0 on success, negative error code on failure

Parameters
  • dev: Pointer to the device structure for codec driver instance.

union audio_dai_cfg_t
#include <codec.h>

Digital Audio Interface Configuration Configuration is dependent on DAI type

Public Members

struct i2s_config i2s
struct audio_codec_cfg
#include <codec.h>

Codec configuration parameters

union audio_property_value_t
#include <codec.h>

Codec property values

Public Members

int vol
bool mute