From: Hans Verkuil Date: Sun, 26 Sep 2010 11:47:38 +0000 (-0300) Subject: V4L/DVB: v4l2: add core serialization lock X-Git-Tag: v2.6.37-rc1~64^2~345 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee6869afc922a9849979e49bb3bbcad794872fcb;p=pandora-kernel.git V4L/DVB: v4l2: add core serialization lock Drivers can optionally set a pointer to a mutex in struct video_device. The core will use that to lock before calling open, read, write, unlocked_ioctl, poll, mmap or release. Updated the documentation as well and ensure that v4l2-event knows about the lock: it will unlock it before doing a blocking wait on an event and relock it afterwards. Ensure that the 'video_is_registered' check is done when the lock is held: a typical disconnect will take the lock as well before unregistering the device nodes, so to prevent race conditions the video_is_registered check should also be done with the lock held. Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Reading git-diff-tree failed