Re: [PATCH v2 3/3] media: imx214: Add new control with V4L2_CID_UNIT_CELL_SIZE

From: Philipp Zabel
Date: Thu Aug 22 2019 - 09:45:05 EST


On Tue, 2019-08-20 at 11:40 +0200, Ricardo Ribalda Delgado wrote:
> According to the product brief, the unit cell size is 1120 nanometers^2.
>
> https://www.sony-semicon.co.jp/products_en/IS/sensor1/img/products/ProductBrief_IMX214_20150428.pdf
>
> Signed-off-by: Ricardo Ribalda Delgado <ribalda@xxxxxxxxxx>
> ---
> drivers/media/i2c/imx214.c | 23 +++++++++++++++++++++++
> 1 file changed, 23 insertions(+)
>
> diff --git a/drivers/media/i2c/imx214.c b/drivers/media/i2c/imx214.c
> index 159a3a604f0e..cc0a013ba7da 100644
> --- a/drivers/media/i2c/imx214.c
> +++ b/drivers/media/i2c/imx214.c
> @@ -47,6 +47,7 @@ struct imx214 {
> struct v4l2_ctrl *pixel_rate;
> struct v4l2_ctrl *link_freq;
> struct v4l2_ctrl *exposure;
> + struct v4l2_ctrl *unit_size;

This is never used.

Neither are pixel_rate and exposure, it appears. And link_freq is only
used locally in imx214_probe to set the read-only flag.

>
> struct regulator_bulk_data supplies[IMX214_NUM_SUPPLIES];
>
> @@ -941,6 +942,26 @@ static int __maybe_unused imx214_resume(struct device *dev)
> return ret;
> }
>
> +static void unit_size_init(const struct v4l2_ctrl *ctrl, u32 idx,
> + union v4l2_ctrl_ptr ptr)
> +{
> + ptr.p_area->width = 1120;
> + ptr.p_area->height = 1120;
> +}
> +
> +static const struct v4l2_ctrl_type_ops unit_size_ops = {
> + .init = unit_size_init,
> +};
> +
> +static struct v4l2_ctrl *new_unit_size_ctrl(struct v4l2_ctrl_handler *handler)
> +{
> + static struct v4l2_ctrl_config ctrl = {
> + .id = V4L2_CID_UNIT_CELL_SIZE,
> + .type_ops = &unit_size_ops,
> + };
> +
> + return v4l2_ctrl_new_custom(handler, &ctrl, NULL);
> +}
> static int imx214_probe(struct i2c_client *client)
> {
> struct device *dev = &client->dev;
> @@ -1029,6 +1050,8 @@ static int imx214_probe(struct i2c_client *client)
> V4L2_CID_EXPOSURE,
> 0, 3184, 1, 0x0c70);
>
> + imx214->unit_size = new_unit_size_ctrl(&imx214->ctrls);
> +
> ret = imx214->ctrls.error;
> if (ret) {
> dev_err(&client->dev, "%s control init failed (%d)\n",

This seems like a lot of parts to assemble in every sensor driver just
to provide a constant area control. Should this be turned into a
v4l2_ctrl_new_area helper that takes a const struct v4l2_area as an
argument?

static const struct v4l2_area unit_cell_size = {
.width = 1120,
.height = 1120
};

v4l2_ctrl_new_area(&imx214->ctrls, V4L2_CID_UNIT_CELL_SIZE,
&unit_cell_size);

regards
Philipp