blob: 772833b69bbf0523bc63e07e7a7483d2ab4695a8 [file] [log] [blame]
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -03001/*
2 V4L2 device support.
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#include <linux/types.h>
22#include <linux/ioctl.h>
23#include <linux/i2c.h>
24#include <linux/videodev2.h>
25#include <media/v4l2-device.h>
26
27int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev)
28{
Hans Verkuil3a63e4492009-02-14 11:54:23 -030029 if (v4l2_dev == NULL)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030030 return -EINVAL;
Hans Verkuil3a63e4492009-02-14 11:54:23 -030031
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030032 INIT_LIST_HEAD(&v4l2_dev->subdevs);
33 spin_lock_init(&v4l2_dev->lock);
34 v4l2_dev->dev = dev;
Hans Verkuil3a63e4492009-02-14 11:54:23 -030035 if (dev == NULL) {
36 /* If dev == NULL, then name must be filled in by the caller */
37 WARN_ON(!v4l2_dev->name[0]);
38 return 0;
39 }
40
41 /* Set name to driver name + device name if it is empty. */
42 if (!v4l2_dev->name[0])
43 snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
Kay Sieversc3ef01c2009-03-24 16:38:22 -070044 dev->driver->name, dev_name(dev));
Hans Verkuil3a63e4492009-02-14 11:54:23 -030045 if (dev_get_drvdata(dev))
46 v4l2_warn(v4l2_dev, "Non-NULL drvdata on register\n");
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030047 dev_set_drvdata(dev, v4l2_dev);
48 return 0;
49}
50EXPORT_SYMBOL_GPL(v4l2_device_register);
51
Hans Verkuil102e7812009-05-02 10:12:50 -030052int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
53 atomic_t *instance)
54{
55 int num = atomic_inc_return(instance) - 1;
56 int len = strlen(basename);
57
58 if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
59 snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
60 "%s-%d", basename, num);
61 else
62 snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
63 "%s%d", basename, num);
64 return num;
65}
66EXPORT_SYMBOL_GPL(v4l2_device_set_name);
67
Hans Verkuilae6cfaa2009-03-14 08:28:45 -030068void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
69{
70 if (v4l2_dev->dev) {
71 dev_set_drvdata(v4l2_dev->dev, NULL);
72 v4l2_dev->dev = NULL;
73 }
74}
75EXPORT_SYMBOL_GPL(v4l2_device_disconnect);
76
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030077void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
78{
79 struct v4l2_subdev *sd, *next;
80
Hans Verkuil3a63e4492009-02-14 11:54:23 -030081 if (v4l2_dev == NULL)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030082 return;
Hans Verkuilae6cfaa2009-03-14 08:28:45 -030083 v4l2_device_disconnect(v4l2_dev);
84
Hans Verkuil3a63e4492009-02-14 11:54:23 -030085 /* Unregister subdevs */
Hans Verkuilb5b2b7e2009-05-02 10:58:51 -030086 list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -030087 v4l2_device_unregister_subdev(sd);
Randy Dunlapb7fd6062009-05-11 13:37:41 -030088#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
Hans Verkuilb5b2b7e2009-05-02 10:58:51 -030089 if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) {
90 struct i2c_client *client = v4l2_get_subdevdata(sd);
91
92 /* We need to unregister the i2c client explicitly.
93 We cannot rely on i2c_del_adapter to always
94 unregister clients for us, since if the i2c bus
95 is a platform bus, then it is never deleted. */
96 if (client)
97 i2c_unregister_device(client);
98 }
Randy Dunlapb7fd6062009-05-11 13:37:41 -030099#endif
Hans Verkuilb5b2b7e2009-05-02 10:58:51 -0300100 }
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300101}
102EXPORT_SYMBOL_GPL(v4l2_device_unregister);
103
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300104int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
105 struct v4l2_subdev *sd)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300106{
107 /* Check for valid input */
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300108 if (v4l2_dev == NULL || sd == NULL || !sd->name[0])
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300109 return -EINVAL;
110 /* Warn if we apparently re-register a subdev */
Hans Verkuilb0167602009-02-14 12:00:53 -0300111 WARN_ON(sd->v4l2_dev != NULL);
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300112 if (!try_module_get(sd->owner))
113 return -ENODEV;
Hans Verkuilb0167602009-02-14 12:00:53 -0300114 sd->v4l2_dev = v4l2_dev;
Hans Verkuil3a63e4492009-02-14 11:54:23 -0300115 spin_lock(&v4l2_dev->lock);
116 list_add_tail(&sd->list, &v4l2_dev->subdevs);
117 spin_unlock(&v4l2_dev->lock);
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300118 return 0;
119}
120EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
121
122void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
123{
124 /* return if it isn't registered */
Hans Verkuilb0167602009-02-14 12:00:53 -0300125 if (sd == NULL || sd->v4l2_dev == NULL)
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300126 return;
Hans Verkuilb0167602009-02-14 12:00:53 -0300127 spin_lock(&sd->v4l2_dev->lock);
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300128 list_del(&sd->list);
Hans Verkuilb0167602009-02-14 12:00:53 -0300129 spin_unlock(&sd->v4l2_dev->lock);
130 sd->v4l2_dev = NULL;
Hans Verkuil2a1fcdf2008-11-29 21:36:58 -0300131 module_put(sd->owner);
132}
133EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);