aboutsummaryrefslogtreecommitdiff
path: root/drivers/media/v4l2-core/v4l2-device.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/media/v4l2-core/v4l2-device.c')
-rw-r--r--drivers/media/v4l2-core/v4l2-device.c280
1 files changed, 280 insertions, 0 deletions
diff --git a/drivers/media/v4l2-core/v4l2-device.c b/drivers/media/v4l2-core/v4l2-device.c
new file mode 100644
index 00000000000..513969fa695
--- /dev/null
+++ b/drivers/media/v4l2-core/v4l2-device.c
@@ -0,0 +1,280 @@
+/*
+ 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);
+ mutex_init(&v4l2_dev->ioctl_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 */
+ 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))
+ 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;
+
+ if (v4l2_dev == NULL)
+ 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 defined(CONFIG_I2C) || (defined(CONFIG_I2C_MODULE) && defined(MODULE))
+ 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
+ }
+}
+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);
+
+ if (!try_module_get(sd->owner))
+ return -ENODEV;
+
+ sd->v4l2_dev = v4l2_dev;
+ if (sd->internal_ops && sd->internal_ops->registered) {
+ err = sd->internal_ops->registered(sd);
+ if (err) {
+ module_put(sd->owner);
+ return err;
+ }
+ }
+
+ /* 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) {
+ if (sd->internal_ops && sd->internal_ops->unregistered)
+ sd->internal_ops->unregistered(sd);
+ module_put(sd->owner);
+ return err;
+ }
+
+#if defined(CONFIG_MEDIA_CONTROLLER)
+ /* Register the entity. */
+ if (v4l2_dev->mdev) {
+ err = media_device_register_entity(v4l2_dev->mdev, entity);
+ if (err < 0) {
+ if (sd->internal_ops && sd->internal_ops->unregistered)
+ sd->internal_ops->unregistered(sd);
+ module_put(sd->owner);
+ return err;
+ }
+ }
+#endif
+
+ 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);
+
+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.v4l.major = VIDEO_MAJOR;
+ sd->entity.info.v4l.minor = vdev->minor;
+#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)
+ media_device_unregister_entity(&sd->entity);
+#endif
+ video_unregister_device(sd->devnode);
+ module_put(sd->owner);
+}
+EXPORT_SYMBOL_GPL(v4l2_device_unregister_subdev);
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-11-23 04:50:28 +0000