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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);
typedef void (*snd_avirt_pcm_exttrigger)(void);
/**
* ALSA copy_kernel function type
* A standard PCM operation from ALSA. This is used in AVIRT to copy PCM data
* between Audio Paths, along given routes.
*/
typedef int (*snd_pcm_copy_kernel)(struct snd_pcm_substream *substream,
int channel, unsigned long pos, void *buf,
unsigned long bytes);
/*
* AVIRT route source/sink enumeration types
*/
typedef enum snd_avirt_route_endpoint_t {
SND_AVIRT_ROUTE_SOURCE,
SND_AVIRT_ROUTE_SINK,
} snd_avirt_route_endpoint;
/**
* Audio routing
*/
struct snd_avirt_route {
char uid[MAX_NAME_LEN]; /* Unique identifier */
unsigned int channels; /* Route stream channel count */
unsigned int direction; /* Route stream direction */
struct snd_avirt_audiopath *endpoint_ap[2]; /* Source/sink */
struct config_item item; /* configfs item reference */
};
/**
* AVIRT Audio Path info
*/
typedef struct snd_avirt_audiopath snd_avirt_audiopath;
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_playback_ops; /* ALSA PCM playback ops */
const struct snd_pcm_ops *pcm_capture_ops; /* ALSA PCM capture ops */
snd_avirt_audiopath_configure configure; /* Config callback function */
snd_avirt_pcm_exttrigger pcm_exttrigger; /* External trigger callback */
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 snd_pcm_ops *pcm_ops; /* ALSA PCM ops */
struct snd_avirt_route *route; /* Associated route, if any */
struct config_item item; /* configfs item reference */
};
/**
* Audio stream group
*/
struct snd_avirt_stream_array {
struct snd_avirt_stream *streams[MAX_STREAMS];
int count;
};
/**
* snd_avirt_private_free - free Audio Path private data from function prototype
* @pcm: The PCM object
*/
typedef void (*snd_avirt_ap_private_free)(struct snd_pcm *pcm);
/**
* Private Data Expansion
*/
struct snd_avirt_private_data {
/* Initial Audio Path in the route */
struct snd_avirt_audiopath *audiopath;
/* Private data for source/sink Audio Paths */
void *ap_private_data[2];
snd_avirt_ap_private_free ap_private_free;
};
/**
* 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_audiopath_get - get Audio Path by it's UID
* @uid: The Audio Path UID to get
* @return: The Audio Path if it exists, NULL otherwise.
*/
struct snd_avirt_audiopath *snd_avirt_audiopath_get(const char *uid);
/*
* snd_avirt_audiopath_set_private_data - set PCM private data for an Audio Path
* @ap: The Audio Path whose private data to set.
* @pcm: The PCM where the private data is stored.
* @ap_private_data: The value to set to the private data.
* @return: 0 on success, -1 on failure.
*/
int snd_avirt_audiopath_set_private_data(struct snd_avirt_audiopath *ap,
struct snd_pcm *pcm,
void *ap_private_data);
/*
* snd_avirt_audiopath_get_private_data - get PCM private data for an Audio Path
* @ap: The Audio Path whose private data to get.
* @pcm: The PCM where the private data is stored.
* @return: The value assigned to the private data.
*/
void *snd_avirt_audiopath_get_private_data(struct snd_avirt_audiopath *ap,
struct snd_pcm *pcm);
/**
* snd_avirt_route_endpoint_copy - get endpoint copy function for a given
* Audio Path's source/sink.
* @ap: The Audio Path whose endpoint copy function to find.
* @endpoint: The endpoint (SND_AVIRT_ROUTE_SOURCE or SND_AVIRT_ROUTE_SINK).
* @return: A snd_pcm_copy_kernel function pointer that can be used to either:
* 1. Source PCM data into the Audio Path, or,
* 2. Sink PCM data out of the Audio Path.
* If no Audio Path endpoint is routed for 'endpoint', NULL is returned.
*/
snd_pcm_copy_kernel
snd_avirt_route_endpoint_copy(struct snd_pcm_substream *substream,
snd_avirt_route_endpoint endpoint);
/**
* snd_avirt_route_endpoint_trigger - Trigger an Audio Path's endpoint
* (sink/source).
* @uid: The Audio Path whose endpoint trigger function to call.
* @endpoint: The endpoint (SND_AVIRT_ROUTE_SOURCE or SND_AVIRT_ROUTE_SINK).
* @return: 0 on success or -1 on failure.
*/
int snd_avirt_route_endpoint_trigger(struct snd_pcm_substream *substream,
snd_avirt_route_endpoint endpoint);
#endif // __SOUND_AVIRT_H
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