From 503c3d829eaf48837dd5bff5d97ad66369bb955a Mon Sep 17 00:00:00 2001 From: Laurent Pinchart Date: Sun, 7 Mar 2010 15:04:59 -0300 Subject: [media] media: Entity use count Due to the wide differences between drivers regarding power management needs, the media controller does not implement power management. However, the media_entity structure includes a use_count field that media drivers can use to track the number of users of every entity for power management needs. The use_count field is owned by media drivers and must not be touched by entity drivers. Access to the field must be protected by the media device graph_mutex lock. Signed-off-by: Laurent Pinchart Acked-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- drivers/media/media-device.c | 1 + 1 file changed, 1 insertion(+) (limited to 'drivers/media/media-device.c') diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c index a36509a1df09..d2bc809d7a2a 100644 --- a/drivers/media/media-device.c +++ b/drivers/media/media-device.c @@ -73,6 +73,7 @@ int __must_check media_device_register(struct media_device *mdev) mdev->entity_id = 1; INIT_LIST_HEAD(&mdev->entities); spin_lock_init(&mdev->lock); + mutex_init(&mdev->graph_mutex); /* Register the device node. */ mdev->devnode.fops = &media_device_fops; -- cgit v1.2.3