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// SPDX-License-Identifier: GPL-2.0
/*
* AVIRT - ALSA Virtual Soundcard
*
* Copyright (c) 2010-2018 Fiberdyne Systems Pty Ltd
*
* avirt.h - AVIRT system-level header
*/
#ifndef __SOUND_AVIRT_H
#define __SOUND_AVIRT_H
#include <sound/core.h>
#include <sound/pcm.h>
#include <linux/configfs.h>
#define MAX_STREAMS 16
#define MAX_NAME_LEN 80
#define DINFO(logname, fmt, args...) \
snd_printk(KERN_INFO "AVIRT: %s: " fmt "\n", logname, ##args)
#define DERROR(logname, fmt, args...) \
snd_printk(KERN_ERR "AVIRT: %s: " fmt "\n", logname, ##args)
#define DDEBUG(logname, fmt, args...) \
snd_printk(KERN_DEBUG "AVIRT: %s: " fmt "\n", logname, ##args)
struct snd_avirt_stream_array; /* Forward declaration */
/**
* AVIRT Audio Path configure function type
* Each Audio Path registers this at snd_avirt_audiopath_register time.
* It is then called by the core once AVIRT has been configured
*/
typedef int (*snd_avirt_audiopath_configure)(
struct snd_card *card, struct snd_avirt_stream_array *stream_array);
/**
* AVIRT Audio Path info
*/
struct snd_avirt_audiopath {
const char *uid; /* Unique identifier */
const char *name; /* Pretty name */
unsigned int version[3]; /* Version - Major.Minor.Ext */
const struct snd_pcm_hardware *hw; /* ALSA PCM HW conf */
const struct snd_pcm_ops *pcm_ops; /* ALSA PCM op table */
snd_avirt_audiopath_configure configure; /* Config callback function */
void *context;
};
/**
* Audio stream configuration
*/
struct snd_avirt_stream {
char name[MAX_NAME_LEN]; /* Stream name */
char map[MAX_NAME_LEN]; /* Stream Audio Path mapping */
unsigned int channels; /* Stream channel count */
unsigned int device; /* Stream PCM device no. */
unsigned int direction; /* Stream direction */
struct snd_pcm *pcm; /* ALSA PCM */
struct config_item item; /* configfs item reference */
};
/**
* Private Data Expansion
*/
struct snd_avirt_private_data {
struct snd_avirt_audiopath *audiopath;
void *ap_private_data;
void (*ap_private_free)(struct snd_pcm *pcm);
};
/**
* Audio stream group
*/
struct snd_avirt_stream_array {
struct snd_avirt_stream *streams[MAX_STREAMS];
int count;
};
/**
* snd_avirt_audiopath_register - register Audio Path with AVIRT
* @audiopath: Audio Path to be registered
* @return: 0 on success or error code otherwise
*/
int snd_avirt_audiopath_register(struct snd_avirt_audiopath *audiopath);
/**
* snd_avirt_audiopath_deregister - deregister Audio Path with AVIRT
* @audiopath: Audio Path to be deregistered
* @return: 0 on success or error code otherwise
*/
int snd_avirt_audiopath_deregister(struct snd_avirt_audiopath *audiopath);
/**
* snd_avirt_pcm_period_elapsed - PCM buffer complete callback
* @substream: pointer to ALSA PCM substream
*
* This should be called from a child Audio Path once it has finished processing
* the PCM buffer
*/
void snd_avirt_pcm_period_elapsed(struct snd_pcm_substream *substream);
#endif // __SOUND_AVIRT_H
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