[RFCv4 08/21] [WAR] v4l2-ctrls: do not clone non-standard controls

From: Alexandre Courbot
Date: Mon Feb 19 2018 - 23:48:27 EST


Only standard controls can be successfully cloned: handler_new_ref, used
by v4l2_ctrl_request_clone(), forcibly calls v4l2_ctrl_new_std() which
fails to find custom controls names, and we eventually hit the condition
that name == NULL in v4l2_ctrl_new().

This prevents us from using non-standard controls with requests, but
that is enough for testing purposes.

Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxxxx>
---
drivers/media/v4l2-core/v4l2-ctrls.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c b/drivers/media/v4l2-core/v4l2-ctrls.c
index 166647817efb..7a81aa5959c3 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -2772,6 +2772,11 @@ int v4l2_ctrl_request_clone(struct v4l2_ctrl_handler *hdl,
if (filter && !filter(ctrl))
continue;
err = handler_new_ref(hdl, ctrl, &new_ref, false);
+ if (err) {
+ printk("%s: handler_new_ref on control %x (%s) returned %d\n", __func__, ctrl->id, ctrl->name, err);
+ err = 0;
+ continue;
+ }
if (err)
break;
if (from->is_request)
--
2.16.1.291.g4437f3f132-goog