Parse V4L2 device tree properties and register controls for them.

Signed-off-by: Alexander Koskovich <akoskovich@pm.me>
---
 drivers/media/i2c/ov8856.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
index e2998cfa0d18..9d7d16ba8911 100644
--- a/drivers/media/i2c/ov8856.c
+++ b/drivers/media/i2c/ov8856.c
@@ -1887,12 +1887,14 @@ static const struct v4l2_ctrl_ops ov8856_ctrl_ops = {
 
 static int ov8856_init_controls(struct ov8856 *ov8856)
 {
+	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
+	struct v4l2_fwnode_device_properties props;
 	struct v4l2_ctrl_handler *ctrl_hdlr;
 	s64 exposure_max, h_blank;
 	int ret;
 
 	ctrl_hdlr = &ov8856->ctrl_handler;
-	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
+	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
 	if (ret)
 		return ret;
 
@@ -1954,6 +1956,15 @@ static int ov8856_init_controls(struct ov8856 *ov8856)
 	if (ctrl_hdlr->error)
 		return ctrl_hdlr->error;
 
+	ret = v4l2_fwnode_device_parse(&client->dev, &props);
+	if (ret)
+		return ret;
+
+	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ov8856_ctrl_ops,
+					      &props);
+	if (ret)
+		return ret;
+
 	ov8856->sd.ctrl_handler = ctrl_hdlr;
 
 	return 0;

-- 
2.53.0

Hi Alexander,

On Tue, Mar 10, 2026 at 04:21:34AM +0000, Alexander Koskovich wrote:
> Parse V4L2 device tree properties and register controls for them.
> 
> Signed-off-by: Alexander Koskovich <akoskovich@pm.me>
> ---
>  drivers/media/i2c/ov8856.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/i2c/ov8856.c b/drivers/media/i2c/ov8856.c
> index e2998cfa0d18..9d7d16ba8911 100644
> --- a/drivers/media/i2c/ov8856.c
> +++ b/drivers/media/i2c/ov8856.c
> @@ -1887,12 +1887,14 @@ static const struct v4l2_ctrl_ops ov8856_ctrl_ops = {
>  
>  static int ov8856_init_controls(struct ov8856 *ov8856)
>  {
> +	struct i2c_client *client = v4l2_get_subdevdata(&ov8856->sd);
> +	struct v4l2_fwnode_device_properties props;
>  	struct v4l2_ctrl_handler *ctrl_hdlr;
>  	s64 exposure_max, h_blank;
>  	int ret;
>  
>  	ctrl_hdlr = &ov8856->ctrl_handler;
> -	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 8);
> +	ret = v4l2_ctrl_handler_init(ctrl_hdlr, 10);
>  	if (ret)
>  		return ret;
>  
> @@ -1954,6 +1956,15 @@ static int ov8856_init_controls(struct ov8856 *ov8856)
>  	if (ctrl_hdlr->error)
>  		return ctrl_hdlr->error;
>  
> +	ret = v4l2_fwnode_device_parse(&client->dev, &props);
> +	if (ret)
> +		return ret;
> +
> +	ret = v4l2_ctrl_new_fwnode_properties(ctrl_hdlr, &ov8856_ctrl_ops,
> +					      &props);
> +	if (ret)
> +		return ret;
> +

It's not a bug introduced in this patch, but freeing the control handler on
error path was broken to begin with: it was never set to the sub-device on
error so the caller can't release it.

Could you fix that before this patch so we can get it backported?

I think it'd be cleanest to add a new label for freeing it and change all
existing returns to gotos.

>  	ov8856->sd.ctrl_handler = ctrl_hdlr;
>  
>  	return 0;
> 

-- 
Kind regards,

Sakari Ailus