xref: /linux/sound/usb/media.h (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * media.h - Media Controller specific ALSA driver code
4  *
5  * Copyright (c) 2019 Shuah Khan <shuah@kernel.org>
6  *
7  */
8 
9 /*
10  * This file adds Media Controller support to the ALSA driver
11  * to use the Media Controller API to share the tuner with DVB
12  * and V4L2 drivers that control the media device.
13  *
14  * The media device is created based on the existing quirks framework.
15  * Using this approach, the media controller API usage can be added for
16  * a specific device.
17  */
18 #ifndef __MEDIA_H
19 
20 #ifdef CONFIG_SND_USB_AUDIO_USE_MEDIA_CONTROLLER
21 
22 #include <linux/media.h>
23 #include <media/media-device.h>
24 #include <media/media-entity.h>
25 #include <media/media-dev-allocator.h>
26 #include <sound/asound.h>
27 
28 struct media_ctl {
29 	struct media_device *media_dev;
30 	struct media_entity media_entity;
31 	struct media_intf_devnode *intf_devnode;
32 	struct media_link *intf_link;
33 	struct media_pad media_pad;
34 	struct media_pipeline media_pipe;
35 };
36 
37 /*
38  * One source pad each for SNDRV_PCM_STREAM_CAPTURE and
39  * SNDRV_PCM_STREAM_PLAYBACK. One for sink pad to link
40  * to AUDIO Source
41  */
42 #define MEDIA_MIXER_PAD_MAX    (SNDRV_PCM_STREAM_LAST + 2)
43 
44 struct media_mixer_ctl {
45 	struct media_device *media_dev;
46 	struct media_entity media_entity;
47 	struct media_intf_devnode *intf_devnode;
48 	struct media_link *intf_link;
49 	struct media_pad media_pad[MEDIA_MIXER_PAD_MAX];
50 	struct media_pipeline media_pipe;
51 };
52 
53 int snd_media_device_create(struct snd_usb_audio *chip,
54 			    struct usb_interface *iface);
55 void snd_media_device_delete(struct snd_usb_audio *chip);
56 int snd_media_stream_init(struct snd_usb_substream *subs, struct snd_pcm *pcm,
57 			  int stream);
58 void snd_media_stream_delete(struct snd_usb_substream *subs);
59 int snd_media_start_pipeline(struct snd_usb_substream *subs);
60 void snd_media_stop_pipeline(struct snd_usb_substream *subs);
61 #else
62 static inline int snd_media_device_create(struct snd_usb_audio *chip,
63 					  struct usb_interface *iface)
64 						{ return 0; }
65 static inline void snd_media_device_delete(struct snd_usb_audio *chip) { }
66 static inline int snd_media_stream_init(struct snd_usb_substream *subs,
67 					struct snd_pcm *pcm, int stream)
68 						{ return 0; }
69 static inline void snd_media_stream_delete(struct snd_usb_substream *subs) { }
70 static inline int snd_media_start_pipeline(struct snd_usb_substream *subs)
71 					{ return 0; }
72 static inline void snd_media_stop_pipeline(struct snd_usb_substream *subs) { }
73 #endif
74 #endif /* __MEDIA_H */
75