diff options
| author | Hans Verkuil <hans.verkuil@cisco.com> | 2014-01-17 15:25:26 +0400 |
|---|---|---|
| committer | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2014-07-17 18:57:16 +0400 |
| commit | 9ea1b7a4b66fddfab9e65e243b72d18371f8d9a5 (patch) | |
| tree | fd8a4887e9fafdd171cb734430511e5a67bf2844 | |
| parent | 000e4f9a5bcf86fb52914c445ce5634b65e910a2 (diff) | |
| download | linux-9ea1b7a4b66fddfab9e65e243b72d18371f8d9a5.tar.xz | |
[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>
| -rw-r--r-- | drivers/media/v4l2-core/v4l2-ctrls.c | 17 | ||||
| -rw-r--r-- | include/media/v4l2-ctrls.h | 3 |
2 files changed, 14 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 */ diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h index ddd9fdf1ac1a..a38bd55909b2 100644 --- a/include/media/v4l2-ctrls.h +++ b/include/media/v4l2-ctrls.h @@ -96,6 +96,8 @@ typedef void (*v4l2_ctrl_notify_fnc)(struct v4l2_ctrl *ctrl, void *priv); * @is_new: Set when the user specified a new value for this control. It * is also set when called from v4l2_ctrl_handler_setup. Drivers * should never set this flag. + * @has_changed: Set when the current value differs from the new value. Drivers + * should never use this flag. * @is_private: If set, then this control is private to its handler and it * will not be added to any other handlers. Drivers can set * this flag. @@ -158,6 +160,7 @@ struct v4l2_ctrl { unsigned int done:1; unsigned int is_new:1; + unsigned int has_changed:1; unsigned int is_private:1; unsigned int is_auto:1; unsigned int is_int:1; |