xref: /linux/drivers/usb/gadget/function/u_uvc.h (revision 41c177cf354126a22443b5c80cec9fdd313e67e1)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * u_uvc.h
4  *
5  * Utility definitions for the uvc function
6  *
7  * Copyright (c) 2013-2014 Samsung Electronics Co., Ltd.
8  *		http://www.samsung.com
9  *
10  * Author: Andrzej Pietrasiewicz <andrzejtp2010@gmail.com>
11  */
12 
13 #ifndef U_UVC_H
14 #define U_UVC_H
15 
16 #include <linux/mutex.h>
17 #include <linux/usb/composite.h>
18 #include <linux/usb/video.h>
19 
20 #define fi_to_f_uvc_opts(f)	container_of(f, struct f_uvc_opts, func_inst)
21 
22 struct f_uvc_opts {
23 	struct usb_function_instance			func_inst;
24 	unsigned int					streaming_interval;
25 	unsigned int					streaming_maxpacket;
26 	unsigned int					streaming_maxburst;
27 
28 	unsigned int					control_interface;
29 	unsigned int					streaming_interface;
30 	char						function_name[32];
31 	unsigned int					last_unit_id;
32 
33 	bool						enable_interrupt_ep;
34 
35 	/*
36 	 * Control descriptors array pointers for full-/high-speed and
37 	 * super-speed. They point by default to the uvc_fs_control_cls and
38 	 * uvc_ss_control_cls arrays respectively. Legacy gadgets must
39 	 * override them in their gadget bind callback.
40 	 */
41 	const struct uvc_descriptor_header * const	*fs_control;
42 	const struct uvc_descriptor_header * const	*ss_control;
43 
44 	/*
45 	 * Streaming descriptors array pointers for full-speed, high-speed and
46 	 * super-speed. They will point to the uvc_[fhs]s_streaming_cls arrays
47 	 * for configfs-based gadgets. Legacy gadgets must initialize them in
48 	 * their gadget bind callback.
49 	 */
50 	const struct uvc_descriptor_header * const	*fs_streaming;
51 	const struct uvc_descriptor_header * const	*hs_streaming;
52 	const struct uvc_descriptor_header * const	*ss_streaming;
53 
54 	/* Default control descriptors for configfs-based gadgets. */
55 	struct uvc_camera_terminal_descriptor		uvc_camera_terminal;
56 	struct uvc_processing_unit_descriptor		uvc_processing;
57 	struct uvc_output_terminal_descriptor		uvc_output_terminal;
58 
59 	/*
60 	 * Control descriptors pointers arrays for full-/high-speed and
61 	 * super-speed. The first element is a configurable control header
62 	 * descriptor, the other elements point to the fixed default control
63 	 * descriptors. Used by configfs only, must not be touched by legacy
64 	 * gadgets.
65 	 */
66 	struct uvc_descriptor_header			*uvc_fs_control_cls[5];
67 	struct uvc_descriptor_header			*uvc_ss_control_cls[5];
68 
69 	/*
70 	 * Control descriptors for extension units. There could be any number
71 	 * of these, including none at all.
72 	 */
73 	struct list_head				extension_units;
74 
75 	/*
76 	 * Streaming descriptors for full-speed, high-speed and super-speed.
77 	 * Used by configfs only, must not be touched by legacy gadgets. The
78 	 * arrays are allocated at runtime as the number of descriptors isn't
79 	 * known in advance.
80 	 */
81 	struct uvc_descriptor_header			**uvc_fs_streaming_cls;
82 	struct uvc_descriptor_header			**uvc_hs_streaming_cls;
83 	struct uvc_descriptor_header			**uvc_ss_streaming_cls;
84 
85 	/*
86 	 * Indexes into the function's string descriptors allowing users to set
87 	 * custom descriptions rather than the hard-coded defaults.
88 	 */
89 	u8						iad_index;
90 	u8						vs0_index;
91 	u8						vs1_index;
92 
93 	/*
94 	 * Read/write access to configfs attributes is handled by configfs.
95 	 *
96 	 * This lock protects the descriptors from concurrent access by
97 	 * read/write and symlink creation/removal.
98 	 */
99 	struct mutex			lock;
100 	int				refcnt;
101 
102 	/*
103 	 * Only for legacy gadget. Shall be NULL for configfs-composed gadgets,
104 	 * which is guaranteed by alloc_inst implementation of f_uvc doing kzalloc.
105 	 */
106 	struct uvcg_streaming_header	*header;
107 };
108 
109 #endif /* U_UVC_H */
110