![Sakari Ailus](/assets/img/avatar_default.png)
Registering a V4L2 sub-device includes, among other things, registering the related media entity and calling the sub-device's registered op. Since patch "media: convert links from array to list", creating a link between two pads requires registering the entity first. If the registered() op involves link creation, the link list head will not be initialised before it is used. Resolve this by first registering the entity, then calling its registered() op. Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
321 lines
8.4 KiB
C
321 lines
8.4 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/module.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/slab.h>
|
|
#if defined(CONFIG_SPI)
|
|
#include <linux/spi/spi.h>
|
|
#endif
|
|
#include <linux/videodev2.h>
|
|
#include <media/v4l2-device.h>
|
|
#include <media/v4l2-ctrls.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_prio_init(&v4l2_dev->prio);
|
|
kref_init(&v4l2_dev->ref);
|
|
get_device(dev);
|
|
v4l2_dev->dev = dev;
|
|
if (dev == NULL) {
|
|
/* If dev == NULL, then name must be filled in by the caller */
|
|
if (WARN_ON(!v4l2_dev->name[0]))
|
|
return -EINVAL;
|
|
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))
|
|
dev_set_drvdata(dev, v4l2_dev);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_register);
|
|
|
|
static void v4l2_device_release(struct kref *ref)
|
|
{
|
|
struct v4l2_device *v4l2_dev =
|
|
container_of(ref, struct v4l2_device, ref);
|
|
|
|
if (v4l2_dev->release)
|
|
v4l2_dev->release(v4l2_dev);
|
|
}
|
|
|
|
int v4l2_device_put(struct v4l2_device *v4l2_dev)
|
|
{
|
|
return kref_put(&v4l2_dev->ref, v4l2_device_release);
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_put);
|
|
|
|
int v4l2_device_set_name(struct v4l2_device *v4l2_dev, const char *basename,
|
|
atomic_t *instance)
|
|
{
|
|
int num = atomic_inc_return(instance) - 1;
|
|
int len = strlen(basename);
|
|
|
|
if (basename[len - 1] >= '0' && basename[len - 1] <= '9')
|
|
snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
|
|
"%s-%d", basename, num);
|
|
else
|
|
snprintf(v4l2_dev->name, sizeof(v4l2_dev->name),
|
|
"%s%d", basename, num);
|
|
return num;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_set_name);
|
|
|
|
void v4l2_device_disconnect(struct v4l2_device *v4l2_dev)
|
|
{
|
|
if (v4l2_dev->dev == NULL)
|
|
return;
|
|
|
|
if (dev_get_drvdata(v4l2_dev->dev) == v4l2_dev)
|
|
dev_set_drvdata(v4l2_dev->dev, NULL);
|
|
put_device(v4l2_dev->dev);
|
|
v4l2_dev->dev = NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_disconnect);
|
|
|
|
void v4l2_device_unregister(struct v4l2_device *v4l2_dev)
|
|
{
|
|
struct v4l2_subdev *sd, *next;
|
|
|
|
/* Just return if v4l2_dev is NULL or if it was already
|
|
* unregistered before. */
|
|
if (v4l2_dev == NULL || !v4l2_dev->name[0])
|
|
return;
|
|
v4l2_device_disconnect(v4l2_dev);
|
|
|
|
/* Unregister subdevs */
|
|
list_for_each_entry_safe(sd, next, &v4l2_dev->subdevs, list) {
|
|
v4l2_device_unregister_subdev(sd);
|
|
#if IS_ENABLED(CONFIG_I2C)
|
|
if (sd->flags & V4L2_SUBDEV_FL_IS_I2C) {
|
|
struct i2c_client *client = v4l2_get_subdevdata(sd);
|
|
|
|
/*
|
|
* We need to unregister the i2c client
|
|
* explicitly. We cannot rely on
|
|
* i2c_del_adapter to always unregister
|
|
* clients for us, since if the i2c bus is a
|
|
* platform bus, then it is never deleted.
|
|
*
|
|
* Device tree or ACPI based devices must not
|
|
* be unregistered as they have not been
|
|
* registered by us, and would not be
|
|
* re-created by just probing the V4L2 driver.
|
|
*/
|
|
if (client &&
|
|
!client->dev.of_node && !client->dev.fwnode)
|
|
i2c_unregister_device(client);
|
|
continue;
|
|
}
|
|
#endif
|
|
#if defined(CONFIG_SPI)
|
|
if (sd->flags & V4L2_SUBDEV_FL_IS_SPI) {
|
|
struct spi_device *spi = v4l2_get_subdevdata(sd);
|
|
|
|
if (spi && !spi->dev.of_node && !spi->dev.fwnode)
|
|
spi_unregister_device(spi);
|
|
continue;
|
|
}
|
|
#endif
|
|
}
|
|
/* Mark as unregistered, thus preventing duplicate unregistrations */
|
|
v4l2_dev->name[0] = '\0';
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_unregister);
|
|
|
|
int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
|
|
struct v4l2_subdev *sd)
|
|
{
|
|
#if defined(CONFIG_MEDIA_CONTROLLER)
|
|
struct media_entity *entity = &sd->entity;
|
|
#endif
|
|
int err;
|
|
|
|
/* 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);
|
|
|
|
/*
|
|
* The reason to acquire the module here is to avoid unloading
|
|
* a module of sub-device which is registered to a media
|
|
* device. To make it possible to unload modules for media
|
|
* devices that also register sub-devices, do not
|
|
* try_module_get() such sub-device owners.
|
|
*/
|
|
sd->owner_v4l2_dev = v4l2_dev->dev && v4l2_dev->dev->driver &&
|
|
sd->owner == v4l2_dev->dev->driver->owner;
|
|
|
|
if (!sd->owner_v4l2_dev && !try_module_get(sd->owner))
|
|
return -ENODEV;
|
|
|
|
sd->v4l2_dev = v4l2_dev;
|
|
/* This just returns 0 if either of the two args is NULL */
|
|
err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler, NULL);
|
|
if (err)
|
|
goto error_module;
|
|
|
|
#if defined(CONFIG_MEDIA_CONTROLLER)
|
|
/* Register the entity. */
|
|
if (v4l2_dev->mdev) {
|
|
err = media_device_register_entity(v4l2_dev->mdev, entity);
|
|
if (err < 0)
|
|
goto error_module;
|
|
}
|
|
#endif
|
|
|
|
if (sd->internal_ops && sd->internal_ops->registered) {
|
|
err = sd->internal_ops->registered(sd);
|
|
if (err)
|
|
goto error_unregister;
|
|
}
|
|
|
|
spin_lock(&v4l2_dev->lock);
|
|
list_add_tail(&sd->list, &v4l2_dev->subdevs);
|
|
spin_unlock(&v4l2_dev->lock);
|
|
|
|
return 0;
|
|
|
|
error_unregister:
|
|
#if defined(CONFIG_MEDIA_CONTROLLER)
|
|
media_device_unregister_entity(entity);
|
|
#endif
|
|
error_module:
|
|
if (!sd->owner_v4l2_dev)
|
|
module_put(sd->owner);
|
|
sd->v4l2_dev = NULL;
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
|
|
|
|
static void v4l2_device_release_subdev_node(struct video_device *vdev)
|
|
{
|
|
struct v4l2_subdev *sd = video_get_drvdata(vdev);
|
|
sd->devnode = NULL;
|
|
kfree(vdev);
|
|
}
|
|
|
|
int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
|
|
{
|
|
struct video_device *vdev;
|
|
struct v4l2_subdev *sd;
|
|
int err;
|
|
|
|
/* Register a device node for every subdev marked with the
|
|
* V4L2_SUBDEV_FL_HAS_DEVNODE flag.
|
|
*/
|
|
list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
|
|
if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
|
|
continue;
|
|
|
|
vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
|
|
if (!vdev) {
|
|
err = -ENOMEM;
|
|
goto clean_up;
|
|
}
|
|
|
|
video_set_drvdata(vdev, sd);
|
|
strlcpy(vdev->name, sd->name, sizeof(vdev->name));
|
|
vdev->v4l2_dev = v4l2_dev;
|
|
vdev->fops = &v4l2_subdev_fops;
|
|
vdev->release = v4l2_device_release_subdev_node;
|
|
vdev->ctrl_handler = sd->ctrl_handler;
|
|
err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
|
|
sd->owner);
|
|
if (err < 0) {
|
|
kfree(vdev);
|
|
goto clean_up;
|
|
}
|
|
#if defined(CONFIG_MEDIA_CONTROLLER)
|
|
sd->entity.info.dev.major = VIDEO_MAJOR;
|
|
sd->entity.info.dev.minor = vdev->minor;
|
|
|
|
/* Interface is created by __video_register_device() */
|
|
if (vdev->v4l2_dev->mdev) {
|
|
struct media_link *link;
|
|
|
|
link = media_create_intf_link(&sd->entity,
|
|
&vdev->intf_devnode->intf,
|
|
MEDIA_LNK_FL_ENABLED);
|
|
if (!link)
|
|
goto clean_up;
|
|
}
|
|
#endif
|
|
sd->devnode = vdev;
|
|
}
|
|
return 0;
|
|
|
|
clean_up:
|
|
list_for_each_entry(sd, &v4l2_dev->subdevs, list) {
|
|
if (!sd->devnode)
|
|
break;
|
|
video_unregister_device(sd->devnode);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes);
|
|
|
|
void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
|
|
{
|
|
struct v4l2_device *v4l2_dev;
|
|
|
|
/* return if it isn't registered */
|
|
if (sd == NULL || sd->v4l2_dev == NULL)
|
|
return;
|
|
|
|
v4l2_dev = sd->v4l2_dev;
|
|
|
|
spin_lock(&v4l2_dev->lock);
|
|
list_del(&sd->list);
|
|
spin_unlock(&v4l2_dev->lock);
|
|
|
|
if (sd->internal_ops && sd->internal_ops->unregistered)
|
|
sd->internal_ops->unregistered(sd);
|
|
sd->v4l2_dev = NULL;
|
|
|
|
#if defined(CONFIG_MEDIA_CONTROLLER)
|
|
if (v4l2_dev->mdev) {
|
|
/*
|
|
* No need to explicitly remove links, as both pads and
|
|
* links are removed by the function below, in the right order
|
|
*/
|
|
media_device_unregister_entity(&sd->entity);
|
|
}
|
|
#endif
|
|
video_unregister_device(sd->devnode);
|
|
if (!sd->owner_v4l2_dev)
|
|
module_put(sd->owner);
|
|
}
|
|
EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);
|