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authorHans Verkuil <hans.verkuil@cisco.com>2014-01-17 08:25:26 -0300
committerMauro Carvalho Chehab <m.chehab@samsung.com>2014-07-17 11:57:16 -0300
commit9ea1b7a4b66fddfab9e65e243b72d18371f8d9a5 (patch)
treefd8a4887e9fafdd171cb734430511e5a67bf2844 /drivers/media
parent000e4f9a5bcf86fb52914c445ce5634b65e910a2 (diff)
downloadblackbird-obmc-linux-9ea1b7a4b66fddfab9e65e243b72d18371f8d9a5.tar.gz
blackbird-obmc-linux-9ea1b7a4b66fddfab9e65e243b72d18371f8d9a5.zip
[media] v4l2-ctrls: compare values only once
When setting a control the control's new value is compared to the current value twice: once by new_to_cur(), once by cluster_changed(). Not a big deal when dealing with simple values, but it can be a problem when dealing with compound types or arrays. So fix this: cluster_changed() sets the has_changed flag, which is used by new_to_cur() instead of having to do another compare. Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com> Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com> Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Diffstat (limited to 'drivers/media')
-rw-r--r--drivers/media/v4l2-core/v4l2-ctrls.c17
1 files changed, 11 insertions, 6 deletions
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index e7e0beab7048..1b4d37ce4afe 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1424,8 +1424,11 @@ static void new_to_cur(struct v4l2_fh *fh, struct v4l2_ctrl *ctrl, u32 ch_flags)
if (ctrl == NULL)
return;
- changed = !ctrl->type_ops->equal(ctrl, ctrl->p_cur, ctrl->p_new);
- ptr_to_ptr(ctrl, ctrl->p_new, ctrl->p_cur);
+
+ /* has_changed is set by cluster_changed */
+ changed = ctrl->has_changed;
+ if (changed)
+ ptr_to_ptr(ctrl, ctrl->p_new, ctrl->p_cur);
if (ch_flags & V4L2_EVENT_CTRL_CH_FLAGS) {
/* Note: CH_FLAGS is only set for auto clusters. */
@@ -1462,17 +1465,19 @@ static void cur_to_new(struct v4l2_ctrl *ctrl)
value that differs from the current value. */
static int cluster_changed(struct v4l2_ctrl *master)
{
- int diff = 0;
+ bool changed = false;
int i;
- for (i = 0; !diff && i < master->ncontrols; i++) {
+ for (i = 0; i < master->ncontrols; i++) {
struct v4l2_ctrl *ctrl = master->cluster[i];
if (ctrl == NULL)
continue;
- diff = !ctrl->type_ops->equal(ctrl, ctrl->p_cur, ctrl->p_new);
+ ctrl->has_changed = !ctrl->type_ops->equal(ctrl,
+ ctrl->p_cur, ctrl->p_new);
+ changed |= ctrl->has_changed;
}
- return diff;
+ return changed;
}
/* Control range checking */
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