Hans Verkuil | 2a1fcdf | 2008-11-29 21:36:58 -0300 | [diff] [blame] | 1 | /* |
| 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 | |
| 27 | int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev) |
| 28 | { |
| 29 | if (dev == NULL || v4l2_dev == NULL) |
| 30 | return -EINVAL; |
| 31 | /* Warn if we apparently re-register a device */ |
Mauro Carvalho Chehab | 4326633 | 2009-01-05 01:42:38 -0300 | [diff] [blame] | 32 | WARN_ON(dev_get_drvdata(dev) != NULL); |
Hans Verkuil | 2a1fcdf | 2008-11-29 21:36:58 -0300 | [diff] [blame] | 33 | INIT_LIST_HEAD(&v4l2_dev->subdevs); |
| 34 | spin_lock_init(&v4l2_dev->lock); |
| 35 | v4l2_dev->dev = dev; |
| 36 | snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s", |
Kay Sievers | c3ef01c | 2009-03-24 16:38:22 -0700 | [diff] [blame^] | 37 | dev->driver->name, dev_name(dev)); |
Hans Verkuil | 2a1fcdf | 2008-11-29 21:36:58 -0300 | [diff] [blame] | 38 | dev_set_drvdata(dev, v4l2_dev); |
| 39 | return 0; |
| 40 | } |
| 41 | EXPORT_SYMBOL_GPL(v4l2_device_register); |
| 42 | |
| 43 | void v4l2_device_unregister(struct v4l2_device *v4l2_dev) |
| 44 | { |
| 45 | struct v4l2_subdev *sd, *next; |
| 46 | |
| 47 | if (v4l2_dev == NULL || v4l2_dev->dev == NULL) |
| 48 | return; |
| 49 | dev_set_drvdata(v4l2_dev->dev, NULL); |
| 50 | /* unregister subdevs */ |
| 51 | list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) |
| 52 | v4l2_device_unregister_subdev(sd); |
| 53 | |
| 54 | v4l2_dev->dev = NULL; |
| 55 | } |
| 56 | EXPORT_SYMBOL_GPL(v4l2_device_unregister); |
| 57 | |
| 58 | int v4l2_device_register_subdev(struct v4l2_device *dev, struct v4l2_subdev *sd) |
| 59 | { |
| 60 | /* Check for valid input */ |
| 61 | if (dev == NULL || sd == NULL || !sd->name[0]) |
| 62 | return -EINVAL; |
| 63 | /* Warn if we apparently re-register a subdev */ |
Mauro Carvalho Chehab | 4326633 | 2009-01-05 01:42:38 -0300 | [diff] [blame] | 64 | WARN_ON(sd->dev != NULL); |
Hans Verkuil | 2a1fcdf | 2008-11-29 21:36:58 -0300 | [diff] [blame] | 65 | if (!try_module_get(sd->owner)) |
| 66 | return -ENODEV; |
| 67 | sd->dev = dev; |
| 68 | spin_lock(&dev->lock); |
| 69 | list_add_tail(&sd->list, &dev->subdevs); |
| 70 | spin_unlock(&dev->lock); |
| 71 | return 0; |
| 72 | } |
| 73 | EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); |
| 74 | |
| 75 | void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) |
| 76 | { |
| 77 | /* return if it isn't registered */ |
| 78 | if (sd == NULL || sd->dev == NULL) |
| 79 | return; |
| 80 | spin_lock(&sd->dev->lock); |
| 81 | list_del(&sd->list); |
| 82 | spin_unlock(&sd->dev->lock); |
| 83 | sd->dev = NULL; |
| 84 | module_put(sd->owner); |
| 85 | } |
| 86 | EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); |