linux/sound/usb/media.h

/* SPDX-License-Identifier: GPL-2.0+ */
/*
 * media.h - Media Controller specific ALSA driver code
 *
 * Copyright (c) 2019 Shuah Khan <[email protected]>
 *
 */

/*
 * This file adds Media Controller support to the ALSA driver
 * to use the Media Controller API to share the tuner with DVB
 * and V4L2 drivers that control the media device.
 *
 * The media device is created based on the existing quirks framework.
 * Using this approach, the media controller API usage can be added for
 * a specific device.
 */
#ifndef __MEDIA_H

#ifdef CONFIG_SND_USB_AUDIO_USE_MEDIA_CONTROLLER

#include <linux/media.h>
#include <media/media-device.h>
#include <media/media-entity.h>
#include <media/media-dev-allocator.h>
#include <sound/asound.h>

struct media_ctl { … };

/*
 * One source pad each for SNDRV_PCM_STREAM_CAPTURE and
 * SNDRV_PCM_STREAM_PLAYBACK. One for sink pad to link
 * to AUDIO Source
 */
#define MEDIA_MIXER_PAD_MAX …

struct media_mixer_ctl { … };

int snd_media_device_create(struct snd_usb_audio *chip,
			    struct usb_interface *iface);
void snd_media_device_delete(struct snd_usb_audio *chip);
int snd_media_stream_init(struct snd_usb_substream *subs, struct snd_pcm *pcm,
			  int stream);
void snd_media_stream_delete(struct snd_usb_substream *subs);
int snd_media_start_pipeline(struct snd_usb_substream *subs);
void snd_media_stop_pipeline(struct snd_usb_substream *subs);
#else
static inline int snd_media_device_create(struct snd_usb_audio *chip,
					  struct usb_interface *iface)
						{ return 0; }
static inline void snd_media_device_delete(struct snd_usb_audio *chip) { }
static inline int snd_media_stream_init(struct snd_usb_substream *subs,
					struct snd_pcm *pcm, int stream)
						{ return 0; }
static inline void snd_media_stream_delete(struct snd_usb_substream *subs) { }
static inline int snd_media_start_pipeline(struct snd_usb_substream *subs)
					{ return 0; }
static inline void snd_media_stop_pipeline(struct snd_usb_substream *subs) { }
#endif
#endif /* __MEDIA_H */