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![Hans Verkuil](/assets/img/avatar_default.png)
Add a utility function that can be used to setup the v4l2_device's name field in a standard manner. Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
142 lines
5.6 KiB
C
142 lines
5.6 KiB
C
/*
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V4L2 device support header.
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Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#ifndef _V4L2_DEVICE_H
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#define _V4L2_DEVICE_H
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#include <media/v4l2-subdev.h>
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/* Each instance of a V4L2 device should create the v4l2_device struct,
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either stand-alone or embedded in a larger struct.
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It allows easy access to sub-devices (see v4l2-subdev.h) and provides
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basic V4L2 device-level support.
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*/
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#define V4L2_DEVICE_NAME_SIZE (20 + 16)
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struct v4l2_device {
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/* dev->driver_data points to this struct.
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Note: dev might be NULL if there is no parent device
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as is the case with e.g. ISA devices. */
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struct device *dev;
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/* used to keep track of the registered subdevs */
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struct list_head subdevs;
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/* lock this struct; can be used by the driver as well if this
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struct is embedded into a larger struct. */
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spinlock_t lock;
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/* unique device name, by default the driver name + bus ID */
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char name[V4L2_DEVICE_NAME_SIZE];
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/* notify callback called by some sub-devices. */
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void (*notify)(struct v4l2_subdev *sd,
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unsigned int notification, void *arg);
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};
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/* Initialize v4l2_dev and make dev->driver_data point to v4l2_dev.
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dev may be NULL in rare cases (ISA devices). In that case you
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must fill in the v4l2_dev->name field before calling this function. */
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int __must_check v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev);
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/* Optional function to initialize the name field of struct v4l2_device using
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the driver name and a driver-global atomic_t instance.
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This function will increment the instance counter and returns the instance
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value used in the name.
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Example:
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static atomic_t drv_instance = ATOMIC_INIT(0);
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...
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instance = v4l2_device_set_name(&v4l2_dev, "foo", &drv_instance);
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The first time this is called the name field will be set to foo0 and
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this function returns 0. If the name ends with a digit (e.g. cx18),
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then the name will be set to cx18-0 since cx180 looks really odd. */
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int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
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atomic_t *instance);
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/* Set v4l2_dev->dev to NULL. Call when the USB parent disconnects.
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Since the parent disappears this ensures that v4l2_dev doesn't have an
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invalid parent pointer. */
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void v4l2_device_disconnect(struct v4l2_device *v4l2_dev);
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/* Unregister all sub-devices and any other resources related to v4l2_dev. */
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void v4l2_device_unregister(struct v4l2_device *v4l2_dev);
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/* Register a subdev with a v4l2 device. While registered the subdev module
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is marked as in-use. An error is returned if the module is no longer
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loaded when you attempt to register it. */
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int __must_check v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
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struct v4l2_subdev *sd);
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/* Unregister a subdev with a v4l2 device. Can also be called if the subdev
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wasn't registered. In that case it will do nothing. */
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void v4l2_device_unregister_subdev(struct v4l2_subdev *sd);
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/* Iterate over all subdevs. */
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#define v4l2_device_for_each_subdev(sd, v4l2_dev) \
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list_for_each_entry(sd, &(v4l2_dev)->subdevs, list)
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/* Call the specified callback for all subdevs matching the condition.
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Ignore any errors. Note that you cannot add or delete a subdev
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while walking the subdevs list. */
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#define __v4l2_device_call_subdevs(v4l2_dev, cond, o, f, args...) \
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do { \
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struct v4l2_subdev *sd; \
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\
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list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) \
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if ((cond) && sd->ops->o && sd->ops->o->f) \
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sd->ops->o->f(sd , ##args); \
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} while (0)
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/* Call the specified callback for all subdevs matching the condition.
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If the callback returns an error other than 0 or -ENOIOCTLCMD, then
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return with that error code. Note that you cannot add or delete a
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subdev while walking the subdevs list. */
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#define __v4l2_device_call_subdevs_until_err(v4l2_dev, cond, o, f, args...) \
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({ \
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struct v4l2_subdev *sd; \
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long err = 0; \
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\
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list_for_each_entry(sd, &(v4l2_dev)->subdevs, list) { \
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if ((cond) && sd->ops->o && sd->ops->o->f) \
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err = sd->ops->o->f(sd , ##args); \
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if (err && err != -ENOIOCTLCMD) \
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break; \
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} \
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(err == -ENOIOCTLCMD) ? 0 : err; \
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})
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/* Call the specified callback for all subdevs matching grp_id (if 0, then
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match them all). Ignore any errors. Note that you cannot add or delete
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a subdev while walking the subdevs list. */
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#define v4l2_device_call_all(v4l2_dev, grpid, o, f, args...) \
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__v4l2_device_call_subdevs(v4l2_dev, \
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!(grpid) || sd->grp_id == (grpid), o, f , ##args)
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/* Call the specified callback for all subdevs matching grp_id (if 0, then
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match them all). If the callback returns an error other than 0 or
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-ENOIOCTLCMD, then return with that error code. Note that you cannot
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add or delete a subdev while walking the subdevs list. */
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#define v4l2_device_call_until_err(v4l2_dev, grpid, o, f, args...) \
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__v4l2_device_call_subdevs_until_err(v4l2_dev, \
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!(grpid) || sd->grp_id == (grpid), o, f , ##args)
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#endif
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