[media] v4l2-dev/ioctl.c: add vb2_queue support to video_device
This prepares struct video_device for easier integration with vb2.
It also introduces a new lock that protects the vb2_queue. It is up
to the driver to use it or not. And the driver can associate an owner
filehandle with the queue to check whether queuing requests are
permitted for the calling filehandle.
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/include/media/v4l2-ioctl.h b/include/media/v4l2-ioctl.h
index dfd984f..19e9352 100644
--- a/include/media/v4l2-ioctl.h
+++ b/include/media/v4l2-ioctl.h
@@ -304,6 +304,11 @@
then do printk(KERN_DEBUG "%s: ", prefix) first. */
extern void v4l_printk_ioctl(const char *prefix, unsigned int cmd);
+/* Internal use only: get the mutex (if any) that we need to lock for the
+ given command. */
+struct video_device;
+extern struct mutex *v4l2_ioctl_get_lock(struct video_device *vdev, unsigned cmd);
+
/* names for fancy debug output */
extern const char *v4l2_field_names[];
extern const char *v4l2_type_names[];