| /* |
| V4L2 device support. |
| |
| Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl> |
| |
| This program is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or |
| (at your option) any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| GNU General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <linux/types.h> |
| #include <linux/ioctl.h> |
| #include <linux/i2c.h> |
| #include <linux/videodev2.h> |
| #include <media/v4l2-device.h> |
| |
| int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev) |
| { |
| if (v4l2_dev == NULL) |
| return -EINVAL; |
| |
| INIT_LIST_HEAD(&v4l2_dev->subdevs); |
| spin_lock_init(&v4l2_dev->lock); |
| v4l2_dev->dev = dev; |
| if (dev == NULL) { |
| /* If dev == NULL, then name must be filled in by the caller */ |
| WARN_ON(!v4l2_dev->name[0]); |
| return 0; |
| } |
| |
| /* Set name to driver name + device name if it is empty. */ |
| if (!v4l2_dev->name[0]) |
| snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s", |
| dev->driver->name, dev_name(dev)); |
| if (dev_get_drvdata(dev)) |
| v4l2_warn(v4l2_dev, "Non-NULL drvdata on register\n"); |
| dev_set_drvdata(dev, v4l2_dev); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(v4l2_device_register); |
| |
| void v4l2_device_unregister(struct v4l2_device *v4l2_dev) |
| { |
| struct v4l2_subdev *sd, *next; |
| |
| if (v4l2_dev == NULL) |
| return; |
| if (v4l2_dev->dev) |
| dev_set_drvdata(v4l2_dev->dev, NULL); |
| /* Unregister subdevs */ |
| list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) |
| v4l2_device_unregister_subdev(sd); |
| |
| v4l2_dev->dev = NULL; |
| } |
| EXPORT_SYMBOL_GPL(v4l2_device_unregister); |
| |
| int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev, |
| struct v4l2_subdev *sd) |
| { |
| /* Check for valid input */ |
| if (v4l2_dev == NULL || sd == NULL || !sd->name[0]) |
| return -EINVAL; |
| /* Warn if we apparently re-register a subdev */ |
| WARN_ON(sd->v4l2_dev != NULL); |
| if (!try_module_get(sd->owner)) |
| return -ENODEV; |
| sd->v4l2_dev = v4l2_dev; |
| spin_lock(&v4l2_dev->lock); |
| list_add_tail(&sd->list, &v4l2_dev->subdevs); |
| spin_unlock(&v4l2_dev->lock); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(v4l2_device_register_subdev); |
| |
| void v4l2_device_unregister_subdev(struct v4l2_subdev *sd) |
| { |
| /* return if it isn't registered */ |
| if (sd == NULL || sd->v4l2_dev == NULL) |
| return; |
| spin_lock(&sd->v4l2_dev->lock); |
| list_del(&sd->list); |
| spin_unlock(&sd->v4l2_dev->lock); |
| sd->v4l2_dev = NULL; |
| module_put(sd->owner); |
| } |
| EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev); |