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[media] v4l2-ctrls: v4l2_ctrl_handler_setup must set is_new to 1

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Renamed has_new to is_new.

Drivers can use the is_new field to determine if a new value was specified
for a control. The v4l2_ctrl_handler_setup() must always set this to 1 since
the setup has to force a full update of all controls.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Hans Verkuil
2011-01-11 14:45:03 -03:00
committed by Mauro Carvalho Chehab
parent 45f6f84af3
commit 2a863793be
3 changed files with 30 additions and 12 deletions
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12
Documentation/video4linux/v4l2-controls.txt
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@ -285,6 +285,9 @@ implement g_volatile_ctrl like this:
The 'new value' union is not used in g_volatile_ctrl. In general controls
that need to implement g_volatile_ctrl are read-only controls.
Note that if one or more controls in a control cluster are marked as volatile,
then all the controls in the cluster are seen as volatile.
To mark a control as volatile you have to set the is_volatile flag:
ctrl = v4l2_ctrl_new_std(&sd->ctrl_handler, ...);
@ -462,6 +465,15 @@ pointer to the v4l2_ctrl_ops struct that is used for that cluster.
Obviously, all controls in the cluster array must be initialized to either
a valid control or to NULL.
In rare cases you might want to know which controls of a cluster actually
were set explicitly by the user. For this you can check the 'is_new' flag of
each control. For example, in the case of a volume/mute cluster the 'is_new'
flag of the mute control would be set if the user called VIDIOC_S_CTRL for
mute only. If the user would call VIDIOC_S_EXT_CTRLS for both mute and volume
controls, then the 'is_new' flag would be 1 for both controls.
The 'is_new' flag is always 1 when called from v4l2_ctrl_handler_setup().
VIDIOC_LOG_STATUS Support
=========================