struct_snd_compr_ops (9) Linux Manual Page

struct_snd_compr_ops –

Synopsis

struct snd_compr_ops {
    int (*open)(struct snd_compr_stream *stream);
    int (*free)(struct snd_compr_stream *stream);
    int (*set_params)(struct snd_compr_stream *stream, struct snd_compr_params *params);
    int (*get_params)(struct snd_compr_stream *stream, struct snd_codec *params);
    int (*set_metadata)(struct snd_compr_stream *stream, struct snd_compr_metadata *metadata);
    int (*get_metadata)(struct snd_compr_stream *stream, struct snd_compr_metadata *metadata);
    int (*trigger)(struct snd_compr_stream *stream, int cmd);
    int (*pointer)(struct snd_compr_stream *stream, struct snd_compr_tstamp *tstamp);
    int (*copy)(struct snd_compr_stream *stream, char __user *buf, size_t count);
    int (*mmap)(struct snd_compr_stream *stream, struct vm_area_struct *vma);
    int (*ack)(struct snd_compr_stream *stream, size_t bytes);
    int (*get_caps)(struct snd_compr_stream *stream, struct snd_compr_caps *caps);
    int (*get_codec_caps)(struct snd_compr_stream *stream, struct snd_compr_codec_caps *codec);
};

Members

open

Open the compressed stream This callback is mandatory and shall keep dsp ready to receive the stream parameter

free

Close the compressed stream, mandatory

set_params

Sets the compressed stream parameters, mandatory This can be called in during stream creation only to set codec params and the stream properties

get_params

retrieve the codec parameters, mandatory

set_metadata

Set the metadata values for a stream

get_metadata

retrieves the requested metadata values from stream

trigger

Trigger operations like start, pause, resume, drain, stop. This callback is mandatory

pointer

Retrieve current h/w pointer information. Mandatory

copy

Copy the compressed data to/from userspace, Optional Can’t be implemented if DSP supports mmap

mmap

DSP mmap method to mmap DSP memory

ack

Ack for DSP when data is written to audio buffer, Optional Not valid if copy is implemented

get_caps

Retrieve DSP capabilities, mandatory

get_codec_caps

Retrieve capabilities for a specific codec, mandatory

Copyright