mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-29 15:43:59 +08:00
2a1fcdf082
Start implementing a proper v4l2 framework as discussed during the Linux Plumbers Conference 2008. Introduces v4l2_device (for device instances) and v4l2_subdev (representing sub-device instances). Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Reviewed-by: Laurent Pinchart <laurent.pinchart@skynet.be> Reviewed-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Reviewed-by: Andy Walls <awalls@radix.net> Reviewed-by: David Brownell <david-b@pacbell.net> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
87 lines
2.5 KiB
C
87 lines
2.5 KiB
C
/*
|
|
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 (dev == NULL || v4l2_dev == NULL)
|
|
return -EINVAL;
|
|
/* Warn if we apparently re-register a device */
|
|
WARN_ON(dev_get_drvdata(dev));
|
|
INIT_LIST_HEAD(&v4l2_dev->subdevs);
|
|
spin_lock_init(&v4l2_dev->lock);
|
|
v4l2_dev->dev = dev;
|
|
snprintf(v4l2_dev->name, sizeof(v4l2_dev->name), "%s %s",
|
|
dev->driver->name, dev->bus_id);
|
|
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 || v4l2_dev->dev == NULL)
|
|
return;
|
|
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 *dev, struct v4l2_subdev *sd)
|
|
{
|
|
/* Check for valid input */
|
|
if (dev == NULL || sd == NULL || !sd->name[0])
|
|
return -EINVAL;
|
|
/* Warn if we apparently re-register a subdev */
|
|
WARN_ON(sd->dev);
|
|
if (!try_module_get(sd->owner))
|
|
return -ENODEV;
|
|
sd->dev = dev;
|
|
spin_lock(&dev->lock);
|
|
list_add_tail(&sd->list, &dev->subdevs);
|
|
spin_unlock(&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->dev == NULL)
|
|
return;
|
|
spin_lock(&sd->dev->lock);
|
|
list_del(&sd->list);
|
|
spin_unlock(&sd->dev->lock);
|
|
sd->dev = NULL;
|
|
module_put(sd->owner);
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);
|