blob: 8bcbd7a0271cbb6c5143c1f40de2a211d6845baf [file] [log] [blame]
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -03001/*
2 V4L2 device support header.
3
4 Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2 of the License, or
9 (at your option) any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21#ifndef _V4L2_DEVICE_H
22#define _V4L2_DEVICE_H
23
24#include <media/v4l2-subdev.h>
25
26/* Each instance of a V4L2 device should create the v4l2_device struct,
27 either stand-alone or embedded in a larger struct.
28
29 It allows easy access to sub-devices (see v4l2-subdev.h) and provides
30 basic V4L2 device-level support.
31 */
32
Kay Sievers1351a582009-04-16 13:30:38 -030033#define V4L2_DEVICE_NAME_SIZE (20 + 16)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030034
Hans Verkuil09965172010-08-01 14:32:42 -030035struct v4l2_ctrl_handler;
36
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030037struct v4l2_device {
Hans Verkuil3a63e4492009-02-14 11:54:23 -030038 /* dev->driver_data points to this struct.
39 Note: dev might be NULL if there is no parent device
40 as is the case with e.g. ISA devices. */
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030041 struct device *dev;
42 /* used to keep track of the registered subdevs */
43 struct list_head subdevs;
44 /* lock this struct; can be used by the driver as well if this
45 struct is embedded into a larger struct. */
46 spinlock_t lock;
47 /* unique device name, by default the driver name + bus ID */
48 char name[V4L2_DEVICE_NAME_SIZE];
Hans Verkuil98ec6332009-03-08 17:02:10 -030049 /* notify callback called by some sub-devices. */
50 void (*notify)(struct v4l2_subdev *sd,
51 unsigned int notification, void *arg);
Hans Verkuil09965172010-08-01 14:32:42 -030052 /* The control handler. May be NULL. */
53 struct v4l2_ctrl_handler *ctrl_handler;
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030054};
55
Hans Verkuil3a63e4492009-02-14 11:54:23 -030056/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev.
57 dev may be NULL in rare cases (ISA devices). In that case you
58 must fill in the v4l2_dev->name field before calling this function. */
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030059int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
Hans Verkuil102e7812009-05-02 10:12:50 -030060
61/* Optional function to initialize the name field of struct v4l2_device using
62 the driver name and a driver-global atomic_t instance.
63 This function will increment the instance counter and returns the instance
64 value used in the name.
65
66 Example:
67
68 static atomic_t drv_instance = ATOMIC_INIT(0);
69
70 ...
71
72 instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance);
73
74 The first time this is called the name field will be set to foo0 and
75 this function returns 0. If the name ends with a digit (e.g. cx18),
76 then the name will be set to cx18-0 since cx180 looks really odd. */
77int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
78 atomic_t *instance);
79
Hans Verkuilae6cfaa2009-03-14 08:28:45 -030080/* Set v4l2_dev->dev to NULL. Call when the USB parent disconnects.
81 Since the parent disappears this ensures that v4l2_dev doesn't have an
82 invalid parent pointer. */
83void v4l2_device_disconnect(struct v4l2_device *v4l2_dev);
Hans Verkuil102e7812009-05-02 10:12:50 -030084
Hans Verkuilae6cfaa2009-03-14 08:28:45 -030085/* Unregister all sub-devices and any other resources related to v4l2_dev. */
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030086void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
87
88/* Register a subdev with a v4l2 device. While registered the subdev module
89 is marked as in-use. An error is returned if the module is no longer
90 loaded when you attempt to register it. */
Hans Verkuil3a63e4492009-02-14 11:54:23 -030091int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
92 struct v4l2_subdev *sd);
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030093/* Unregister a subdev with a v4l2 device. Can also be called if the subdev
94 wasn't registered. In that case it will do nothing. */
95void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
96
97/* Iterate over all subdevs. */
Hans Verkuil3a63e4492009-02-14 11:54:23 -030098#define v4l2_device_for_each_subdev(sd, v4l2_dev) \
99 list_for_each_entry(sd, &(v4l2_dev)->subdevs, list)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300100
101/* Call the specified callback for all subdevs matching the condition.
102 Ignore any errors. Note that you cannot add or delete a subdev
103 while walking the subdevs list. */
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300104#define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300105 do { \
106 struct v4l2_subdev *sd; \
107 \
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300108 list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) \
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300109 if ((cond) && sd->ops->o && sd->ops->o->f) \
110 sd->ops->o->f(sd , ##args); \
111 } while (0)
112
113/* Call the specified callback for all subdevs matching the condition.
114 If the callback returns an error other than 0 or -ENOIOCTLCMD, then
115 return with that error code. Note that you cannot add or delete a
116 subdev while walking the subdevs list. */
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300117#define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300118({ \
119 struct v4l2_subdev *sd; \
Hans Verkuil069b7472008-12-30 07:04:34 -0300120 long err = 0; \
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300121 \
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300122 list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) { \
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300123 if ((cond) && sd->ops->o && sd->ops->o->f) \
124 err = sd->ops->o->f(sd , ##args); \
125 if (err && err != -ENOIOCTLCMD) \
126 break; \
127 } \
128 (err == -ENOIOCTLCMD) ? 0 : err; \
129})
130
131/* Call the specified callback for all subdevs matching grp_id (if 0, then
132 match them all). Ignore any errors. Note that you cannot add or delete
133 a subdev while walking the subdevs list. */
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300134#define v4l2_device_call_all(v4l2_dev, grpid, o, f, args...) \
135 __v4l2_device_call_subdevs(v4l2_dev, \
Hans Verkuilf9129a22009-01-12 18:12:13 -0300136 !(grpid) || sd->grp_id == (grpid), o, f , ##args)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300137
138/* Call the specified callback for all subdevs matching grp_id (if 0, then
139 match them all). If the callback returns an error other than 0 or
140 -ENOIOCTLCMD, then return with that error code. Note that you cannot
141 add or delete a subdev while walking the subdevs list. */
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300142#define v4l2_device_call_until_err(v4l2_dev, grpid, o, f, args...) \
143 __v4l2_device_call_subdevs_until_err(v4l2_dev, \
Hans Verkuilf9129a22009-01-12 18:12:13 -0300144 !(grpid) || sd->grp_id == (grpid), o, f , ##args)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300145
146#endif