// 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 #include #include #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