[media] v4l2-ctrls.c: add support for V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK

Normally no control events will go to the filehandle that called the
VIDIOC_S_CTRL/VIDIOC_S_EXT_CTRLS ioctls. This is to prevent a feedback
loop.

This can now be overridden by setting the new V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK
flag.

Based on suggestions from Mauro Carvalho Chehab <mchehab@redhat.com> and
Laurent Pinchart <laurent.pinchart@ideasonboard.com>.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil
2011-06-29 08:56:22 -03:00
committed by Mauro Carvalho Chehab
parent 3ad57c3384
commit 60c0732244
3 changed files with 33 additions and 9 deletions

View File

@@ -1832,7 +1832,8 @@ struct v4l2_event {
__u32 reserved[8];
};
#define V4L2_EVENT_SUB_FL_SEND_INITIAL (1 << 0)
#define V4L2_EVENT_SUB_FL_SEND_INITIAL (1 << 0)
#define V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK (1 << 1)
struct v4l2_event_subscription {
__u32 type;