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Diffstat (limited to 'drivers/media/v4l2-core/v4l2-device.c')
-rw-r--r--drivers/media/v4l2-core/v4l2-device.c160
1 files changed, 85 insertions, 75 deletions
diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c
index 02d1b6327117..63b12ef9d4d9 100644
--- a/drivers/media/v4l2-core/v4l2-device.c
+++ b/drivers/media/v4l2-core/v4l2-device.c
@@ -1,31 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
V4L2 device support.
- Copyright (C) 2008 Hans Verkuil <hverkuil@xs4all.nl>
+ Copyright (C) 2008 Hans Verkuil <hverkuil@kernel.org>
- 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>
@@ -37,7 +21,6 @@ int v4l2_device_register(struct device *dev, struct v4l2_device *v4l2_dev)
INIT_LIST_HEAD(&v4l2_dev->subdevs);
spin_lock_init(&v4l2_dev->lock);
- mutex_init(&v4l2_dev->ioctl_lock);
v4l2_prio_init(&v4l2_dev->prio);
kref_init(&v4l2_dev->ref);
get_device(dev);
@@ -115,73 +98,62 @@ void v4l2_device_unregister(struct v4l2_device *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. */
- if (client)
- 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_unregister_device(spi);
- continue;
- }
-#endif
+ if (sd->flags & V4L2_SUBDEV_FL_IS_I2C)
+ v4l2_i2c_subdev_unregister(sd);
+ else if (sd->flags & V4L2_SUBDEV_FL_IS_SPI)
+ v4l2_spi_subdev_unregister(sd);
}
/* 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)
+int __v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
+ struct v4l2_subdev *sd, struct module *module)
{
-#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])
+ if (!v4l2_dev || !sd || sd->v4l2_dev || !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 &&
+ module == v4l2_dev->dev->driver->owner;
- if (!try_module_get(sd->owner))
+ if (!sd->owner_v4l2_dev && !try_module_get(module))
return -ENODEV;
sd->v4l2_dev = v4l2_dev;
- if (sd->internal_ops && sd->internal_ops->registered) {
- err = sd->internal_ops->registered(sd);
- if (err)
- goto error_module;
- }
-
/* 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);
+ err = v4l2_ctrl_add_handler(v4l2_dev->ctrl_handler, sd->ctrl_handler,
+ NULL, true);
if (err)
- goto error_unregister;
+ goto error_module;
#if defined(CONFIG_MEDIA_CONTROLLER)
/* Register the entity. */
if (v4l2_dev->mdev) {
- err = media_device_register_entity(v4l2_dev->mdev, entity);
+ err = media_device_register_entity(v4l2_dev->mdev, &sd->entity);
if (err < 0)
- goto error_unregister;
+ goto error_module;
}
#endif
+ if (sd->internal_ops && sd->internal_ops->registered) {
+ err = sd->internal_ops->registered(sd);
+ if (err)
+ goto error_unregister;
+ }
+
+ sd->owner = module;
+
spin_lock(&v4l2_dev->lock);
list_add_tail(&sd->list, &v4l2_dev->subdevs);
spin_unlock(&v4l2_dev->lock);
@@ -189,23 +161,35 @@ int v4l2_device_register_subdev(struct v4l2_device *v4l2_dev,
return 0;
error_unregister:
- if (sd->internal_ops && sd->internal_ops->unregistered)
- sd->internal_ops->unregistered(sd);
+#if defined(CONFIG_MEDIA_CONTROLLER)
+ media_device_unregister_entity(&sd->entity);
+#endif
error_module:
- module_put(sd->owner);
+ if (!sd->owner_v4l2_dev)
+ module_put(sd->owner);
sd->v4l2_dev = NULL;
return err;
}
-EXPORT_SYMBOL_GPL(v4l2_device_register_subdev);
+EXPORT_SYMBOL_GPL(__v4l2_device_register_subdev);
-static void v4l2_device_release_subdev_node(struct video_device *vdev)
+static void v4l2_subdev_release(struct v4l2_subdev *sd)
{
- struct v4l2_subdev *sd = video_get_drvdata(vdev);
+ struct module *owner = !sd->owner_v4l2_dev ? sd->owner : NULL;
+
+ if (sd->internal_ops && sd->internal_ops->release)
+ sd->internal_ops->release(sd);
sd->devnode = NULL;
+ module_put(owner);
+}
+
+static void v4l2_device_release_subdev_node(struct video_device *vdev)
+{
+ v4l2_subdev_release(video_get_drvdata(vdev));
kfree(vdev);
}
-int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
+int __v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev,
+ bool read_only)
{
struct video_device *vdev;
struct v4l2_subdev *sd;
@@ -218,6 +202,9 @@ int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
if (!(sd->flags & V4L2_SUBDEV_FL_HAS_DEVNODE))
continue;
+ if (sd->devnode)
+ continue;
+
vdev = kzalloc(sizeof(*vdev), GFP_KERNEL);
if (!vdev) {
err = -ENOMEM;
@@ -225,22 +212,40 @@ int v4l2_device_register_subdev_nodes(struct v4l2_device *v4l2_dev)
}
video_set_drvdata(vdev, sd);
- strlcpy(vdev->name, sd->name, sizeof(vdev->name));
+ strscpy(vdev->name, sd->name, sizeof(vdev->name));
+ vdev->dev_parent = sd->dev;
vdev->v4l2_dev = v4l2_dev;
vdev->fops = &v4l2_subdev_fops;
vdev->release = v4l2_device_release_subdev_node;
vdev->ctrl_handler = sd->ctrl_handler;
+ if (read_only)
+ set_bit(V4L2_FL_SUBDEV_RO_DEVNODE, &vdev->flags);
+ sd->devnode = vdev;
err = __video_register_device(vdev, VFL_TYPE_SUBDEV, -1, 1,
sd->owner);
if (err < 0) {
+ sd->devnode = NULL;
kfree(vdev);
goto clean_up;
}
#if defined(CONFIG_MEDIA_CONTROLLER)
- sd->entity.info.v4l.major = VIDEO_MAJOR;
- sd->entity.info.v4l.minor = vdev->minor;
+ 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 |
+ MEDIA_LNK_FL_IMMUTABLE);
+ if (!link) {
+ err = -ENOMEM;
+ goto clean_up;
+ }
+ }
#endif
- sd->devnode = vdev;
}
return 0;
@@ -253,7 +258,7 @@ clean_up:
return err;
}
-EXPORT_SYMBOL_GPL(v4l2_device_register_subdev_nodes);
+EXPORT_SYMBOL_GPL(__v4l2_device_register_subdev_nodes);
void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
{
@@ -275,11 +280,16 @@ void v4l2_device_unregister_subdev(struct v4l2_subdev *sd)
#if defined(CONFIG_MEDIA_CONTROLLER)
if (v4l2_dev->mdev) {
- media_entity_remove_links(&sd->entity);
+ /*
+ * 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);
- module_put(sd->owner);
+ if (sd->devnode)
+ video_unregister_device(sd->devnode);
+ else
+ v4l2_subdev_release(sd);
}
EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);
generated by cgit (git 2.34.1) at 2025-12-25 02:38:25 +0000