pbl_audio_ops Struct Reference

Device driver operations. More...

#include <audio.h>

Data Fields
int(*	init )(const struct pbl_audio *audio)
	Optional.
void(*	get_caps )(const struct pbl_audio *audio, struct pbl_audio_caps *caps)
	Report the capabilities.
int(*	start )(const struct pbl_audio *audio, const struct pbl_audio_stream *stream, int32_t gain_mdb, bool mute)
	Start streaming the ring, applying gain_mdb and mute before any sample reaches the output.
int(*	stop )(const struct pbl_audio *audio)
	Stop streaming.
int(*	set_gain )(const struct pbl_audio *audio, int32_t gain_mdb)
	Optional, required with a variable gain.
int(*	set_mute )(const struct pbl_audio *audio, bool mute)
	Optional.
void(*	sync_for_device )(const struct pbl_audio *audio, void *buf, size_t len)
	Optional.
void(*	sync_for_cpu )(const struct pbl_audio *audio, void *buf, size_t len)
	Optional.
int(*	pointer )(const struct pbl_audio *audio, size_t *frames)
	Optional.

Detailed Description

Device driver operations.

Called with the device lock held, except the sync and pointer operations, which may be called from the driver's interrupt.

Field Documentation

get_caps

void(* pbl_audio_ops::get_caps) (const struct pbl_audio *audio, struct pbl_audio_caps *caps)

Report the capabilities.

Gain fields are ignored on a device linked to a codec.

init

int(* pbl_audio_ops::init) (const struct pbl_audio *audio)

Optional.

Bring the hardware up. Returns 0, -ENODEV if absent, or a negative errno.

pointer

int(* pbl_audio_ops::pointer) (const struct pbl_audio *audio, size_t *frames)

Optional.

Report the frame position of the hardware within the ring.

set_gain

int(* pbl_audio_ops::set_gain) (const struct pbl_audio *audio, int32_t gain_mdb)

Optional, required with a variable gain.

Set the gain while streaming.

set_mute

int(* pbl_audio_ops::set_mute) (const struct pbl_audio *audio, bool mute)

Optional.

Set the mute while streaming; without it, mute sets the lowest gain.

start

int(* pbl_audio_ops::start) (const struct pbl_audio *audio, const struct pbl_audio_stream *stream, int32_t gain_mdb, bool mute)

Start streaming the ring, applying gain_mdb and mute before any sample reaches the output.

Returns 0, -EINVAL for a stream the hardware cannot run, or a negative errno.

stop

int(* pbl_audio_ops::stop) (const struct pbl_audio *audio)

Stop streaming.

pbl_audio_period_elapsed() is not called once it returns.

sync_for_cpu

void(* pbl_audio_ops::sync_for_cpu) (const struct pbl_audio *audio, void *buf, size_t len)

Optional.

Make hardware writes to a capture period visible to the CPU.

sync_for_device

void(* pbl_audio_ops::sync_for_device) (const struct pbl_audio *audio, void *buf, size_t len)

Optional.

Make CPU writes to a playback period visible to the hardware.

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The documentation for this struct was generated from the following file:

• include/pbl/drivers/audio.h