The struct cdev embedded in struct media_devnode contains its own kobj.
Instead of trying to manage its lifetime separately from struct
media_devnode, make the cdev kobj a parent of the struct media_device.dev
kobj.

The cdev will thus be released during unregistering the media_devnode, not
in media_devnode.dev kobj's release callback.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
---
 drivers/media/media-devnode.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/media/media-devnode.c b/drivers/media/media-devnode.c
index aa8030b..69f84a7 100644
--- a/drivers/media/media-devnode.c
+++ b/drivers/media/media-devnode.c

@@ -63,9 +63,6 @@ static void media_devnode_release(struct device *cd)
 
 	mutex_lock(&media_devnode_lock);
 
-	/* Delete the cdev on this minor as well */
-	cdev_del(&devnode->cdev);
-
 	/* Mark device node number as free */
 	clear_bit(devnode->minor, media_devnode_nums);
 

@@ -246,6 +243,7 @@ int __must_check media_devnode_register(struct media_devnode *devnode,
 
 	/* Part 2: Initialize and register the character device */
 	cdev_init(&devnode->cdev, &media_devnode_fops);
+	devnode->cdev.kobj.parent = &devnode->dev.kobj;
 	devnode->cdev.owner = owner;
 
 	ret = cdev_add(&devnode->cdev, MKDEV(MAJOR(media_dev_t), devnode->minor), 1);

@@ -291,6 +289,7 @@ void media_devnode_unregister(struct media_devnode *devnode)
 	clear_bit(MEDIA_FLAG_REGISTERED, &devnode->flags);
 	mutex_unlock(&media_devnode_lock);
 	device_unregister(&devnode->dev);
+	cdev_del(&devnode->cdev);