Support for new field which on v4l2_ext_controls, used to get the
default value of one or more controls.
Signed-off-by: Ricardo Ribalda Delgado <ricardo.riba...@gmail.com>
---
I missed a ;... sorry about that
drivers/media/v4l2-core/v4l2-ctrls.c | 34 +++++++++++++++++++++++++++++-----
1 file changed, 29 insertions(+), 5 deletions(-)
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index 580098ba5c0b..0caae655968e 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -1489,6 +1489,17 @@ static int new_to_user(struct v4l2_ext_control *c,
return ptr_to_user(c, ctrl, ctrl->p_new);
}
+/* Helper function: copy the initial control value back to the caller */
+static int def_to_user(struct v4l2_ext_control *c, struct v4l2_ctrl *ctrl)
+{
+ int idx;
+
+ for (idx = 0; idx < ctrl->elems; idx++)
+ ctrl->type_ops->init(ctrl, idx, ctrl->p_new);
+
+ return ptr_to_user(c, ctrl, ctrl->p_new);
+}
+
/* Helper function: copy the caller-provider value to the given control value
*/
static int user_to_ptr(struct v4l2_ext_control *c,
struct v4l2_ctrl *ctrl,
@@ -2708,7 +2719,9 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler
*hdl,
cs->error_idx = i;
- if (cs->which && V4L2_CTRL_ID2WHICH(id) != cs->which)
+ if (cs->which &&
+ cs->which != V4L2_CTRL_WHICH_DEF_VAL &&
+ V4L2_CTRL_ID2WHICH(id) != cs->which)
return -EINVAL;
/* Old-style private controls are not allowed for
@@ -2787,7 +2800,7 @@ static int prepare_ext_ctrls(struct v4l2_ctrl_handler
*hdl,
whether there are any controls at all. */
static int class_check(struct v4l2_ctrl_handler *hdl, u32 which)
{
- if (!which)
+ if (which == 0 || which == V4L2_CTRL_WHICH_DEF_VAL)
return list_empty(&hdl->ctrl_refs) ? -EINVAL : 0;
return find_ref_lock(hdl, which | 1) ? 0 : -EINVAL;
}
@@ -2801,6 +2814,9 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl,
struct v4l2_ext_controls *cs
struct v4l2_ctrl_helper *helpers = helper;
int ret;
int i, j;
+ bool def_value;
+
+ def_value = (cs->which == V4L2_CTRL_WHICH_DEF_VAL);
cs->error_idx = cs->count;
cs->which = V4L2_CTRL_ID2WHICH(cs->which);
@@ -2827,9 +2843,11 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl,
struct v4l2_ext_controls *cs
for (i = 0; !ret && i < cs->count; i++) {
int (*ctrl_to_user)(struct v4l2_ext_control *c,
- struct v4l2_ctrl *ctrl) = cur_to_user;
+ struct v4l2_ctrl *ctrl);
struct v4l2_ctrl *master;
+ ctrl_to_user = def_value ? def_to_user : cur_to_user;
+
if (helpers[i].mref == NULL)
continue;
@@ -2839,8 +2857,9 @@ int v4l2_g_ext_ctrls(struct v4l2_ctrl_handler *hdl,
struct v4l2_ext_controls *cs
v4l2_ctrl_lock(master);
/* g_volatile_ctrl will update the new control values */
- if ((master->flags & V4L2_CTRL_FLAG_VOLATILE) ||
- (master->has_volatiles && !is_cur_manual(master))) {
+ if (!def_value &&
+ ((master->flags & V4L2_CTRL_FLAG_VOLATILE) ||
+ (master->has_volatiles && !is_cur_manual(master)))) {
for (j = 0; j < master->ncontrols; j++)
cur_to_new(master->cluster[j]);
ret = call_op(master, g_volatile_ctrl);
@@ -3062,6 +3081,11 @@ static int try_set_ext_ctrls(struct v4l2_fh *fh, struct
v4l2_ctrl_handler *hdl,
int ret;
cs->error_idx = cs->count;
+
+ /* Default value cannot be changed */
+ if (cs->which == V4L2_CTRL_WHICH_DEF_VAL)
+ return -EINVAL;
+
cs->which = V4L2_CTRL_ID2WHICH(cs->which);
if (hdl == NULL)
--
2.5.0
--
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