static ssize_t show_name(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
return sprintf(buf, "%.*s\n", (int)sizeof(vdev->name), vdev->name);
}
static ssize_t show_debug(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
return sprintf(buf, "%i\n", vdev->debug);
}
static ssize_t index_show(struct device *cd,
struct device_attribute *attr, char *buf)
{
struct video_device *vdev = to_video_device(cd);
return sprintf(buf, "%i\n", vdev->index);
}
/* Called when the last user of the video device exits. */
static void v4l2_device_release(struct device *cd)
{
struct video_device *vdev = to_video_device(cd);
struct v4l2_device *v4l2_dev = vdev->v4l2_dev;
mutex_lock(&videodev_lock);
if (video_device[vdev->minor] != vdev) {
mutex_unlock(&videodev_lock);
/* should not happen */
WARN_ON(1);
return;
}
/* Free up this device for reuse */
video_device[vdev->minor] = NULL;
/* Delete the cdev on this minor as well */
cdev_del(vdev->cdev);
/* Just in case some driver tries to access this from
the release() callback. */
vdev->cdev = NULL;
/* Mark device node number as free */
devnode_clear(vdev);
mutex_unlock(&videodev_lock);
/* Release video_device and perform other
cleanups as needed. */
vdev->release(vdev);
/* Decrease v4l2_device refcount */
if (v4l2_dev)
v4l2_device_put(v4l2_dev);
}
/* Called when the last user of the video device exits. */
static void v4l2_device_release(struct device *cd)
{
struct video_device *vdev = to_video_device(cd);
struct v4l2_device *v4l2_dev = vdev->v4l2_dev;
mutex_lock(&videodev_lock);
if (WARN_ON(video_device[vdev->minor] != vdev)) {
/* should not happen */
mutex_unlock(&videodev_lock);
return;
}
/* Free up this device for reuse */
video_device[vdev->minor] = NULL;
/* Delete the cdev on this minor as well */
cdev_del(vdev->cdev);
/* Just in case some driver tries to access this from
the release() callback. */
vdev->cdev = NULL;
/* Mark device node number as free */
devnode_clear(vdev);
mutex_unlock(&videodev_lock);
#if defined(CONFIG_MEDIA_CONTROLLER)
if (v4l2_dev->mdev) {
/* Remove interfaces and interface links */
media_devnode_remove(vdev->intf_devnode);
if (vdev->entity.function != MEDIA_ENT_F_UNKNOWN)
media_device_unregister_entity(&vdev->entity);
}
#endif
/* Do not call v4l2_device_put if there is no release callback set.
* Drivers that have no v4l2_device release callback might free the
* v4l2_dev instance in the video_device release callback below, so we
* must perform this check here.
*
* TODO: In the long run all drivers that use v4l2_device should use the
* v4l2_device release callback. This check will then be unnecessary.
*/
if (v4l2_dev->release == NULL)
v4l2_dev = NULL;
/* Release video_device and perform other
cleanups as needed. */
vdev->release(vdev);
/* Decrease v4l2_device refcount */
if (v4l2_dev)
v4l2_device_put(v4l2_dev);
}
static ssize_t debug_store(struct device *cd, struct device_attribute *attr,
const char *buf, size_t len)
{
struct video_device *vdev = to_video_device(cd);
int res = 0;
u16 value;
res = kstrtou16(buf, 0, &value);
if (res)
return res;
vdev->debug = value;
return len;
}
/* Called when the last user of the video device exits. */
static void v4l2_device_release(struct device *cd)
{
struct video_device *vdev = to_video_device(cd);
struct v4l2_device *v4l2_dev = vdev->v4l2_dev;
mutex_lock(&videodev_lock);
if (video_device[vdev->minor] != vdev) {
mutex_unlock(&videodev_lock);
/* should not happen */
WARN_ON(1);
return;
}
/* Free up this device for reuse */
video_device[vdev->minor] = NULL;
/* Delete the cdev on this minor as well */
cdev_del(vdev->cdev);
/* Just in case some driver tries to access this from
the release() callback. */
vdev->cdev = NULL;
/* Mark device node number as free */
devnode_clear(vdev);
mutex_unlock(&videodev_lock);
#if defined(CONFIG_MEDIA_CONTROLLER)
if (vdev->v4l2_dev && vdev->v4l2_dev->mdev &&
vdev->vfl_type != VFL_TYPE_SUBDEV)
media_device_unregister_entity(&vdev->entity);
#endif
/* Release video_device and perform other
cleanups as needed. */
vdev->release(vdev);
/* Decrease v4l2_device refcount */
if (v4l2_dev)
v4l2_device_put(v4l2_dev);
}