[07/13] media: i2c: imx214: Use number of lanes from device tree

From: André Apitzsch <git@apitzsch.eu>

The imx214 camera is capable of either two-lane or four-lane operation.

Currently only the four-lane mode is supported, as proper pixel rates
and link frequences for the two-lane mode are unknown.

Signed-off-by: André Apitzsch <git@apitzsch.eu>
---
 drivers/media/i2c/imx214.c | 37 ++++++++++++++++++++++++++++++-------
 1 file changed, 30 insertions(+), 7 deletions(-)

Hi

On Mon, Sep 2, 2024 at 11:53 PM André Apitzsch via B4 Relay
<devnull+git.apitzsch.eu@kernel.org> wrote:
>
> From: André Apitzsch <git@apitzsch.eu>
>
> The imx214 camera is capable of either two-lane or four-lane operation.
>
> Currently only the four-lane mode is supported, as proper pixel rates
> and link frequences for the two-lane mode are unknown.
>
> Signed-off-by: André Apitzsch <git@apitzsch.eu>
> ---
>  drivers/media/i2c/imx214.c | 37 ++++++++++++++++++++++++++++++-------
>  1 file changed, 30 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/media/i2c/imx214.c b/drivers/media/i2c/imx214.c
> index 4507e12dd4cd..3b422cddbdce 100644
> --- a/drivers/media/i2c/imx214.c
> +++ b/drivers/media/i2c/imx214.c
> @@ -195,11 +195,13 @@ struct imx214 {
>         struct regulator_bulk_data      supplies[IMX214_NUM_SUPPLIES];
>
>         struct gpio_desc *enable_gpio;
> +
> +       /* Two or Four lanes */
> +       u8 lanes;
>  };
>
>  /*From imx214_mode_tbls.h*/
>  static const struct cci_reg_sequence mode_4096x2304[] = {
> -       { IMX214_REG_CSI_LANE_MODE, IMX214_CSI_4_LANE_MODE },
>         { IMX214_REG_HDR_MODE, IMX214_HDR_MODE_OFF },
>         { IMX214_REG_HDR_RES_REDUCTION, IMX214_HDR_RES_REDU_THROUGH },
>         { IMX214_REG_EXPOSURE_RATIO, 1 },
> @@ -272,7 +274,6 @@ static const struct cci_reg_sequence mode_4096x2304[] = {
>  };
>
>  static const struct cci_reg_sequence mode_1920x1080[] = {
> -       { IMX214_REG_CSI_LANE_MODE, IMX214_CSI_4_LANE_MODE },
>         { IMX214_REG_HDR_MODE, IMX214_HDR_MODE_OFF },
>         { IMX214_REG_HDR_RES_REDUCTION, IMX214_HDR_RES_REDU_THROUGH },
>         { IMX214_REG_EXPOSURE_RATIO, 1 },
> @@ -774,6 +775,13 @@ static int imx214_ctrls_init(struct imx214 *imx214)
>         return 0;
>  };
>
> +static int imx214_configure_lanes(struct imx214 *imx214)
> +{
> +       return cci_write(imx214->regmap, IMX214_REG_CSI_LANE_MODE,
> +                        imx214->lanes == 2 ? IMX214_CSI_2_LANE_MODE :
> +                        IMX214_CSI_4_LANE_MODE, NULL);
> +};
> +
>  static int imx214_start_streaming(struct imx214 *imx214)
>  {
>         const struct imx214_mode *mode;
> @@ -786,6 +794,13 @@ static int imx214_start_streaming(struct imx214 *imx214)
>                 return ret;
>         }
>
> +       /* Configure two or four Lane mode */
> +       ret = imx214_configure_lanes(imx214);
> +       if (ret) {
> +               dev_err(imx214->dev, "%s failed to configure lanes\n", __func__);
> +               return ret;
> +       }
> +
>         mode = v4l2_find_nearest_size(imx214_modes,
>                                 ARRAY_SIZE(imx214_modes), width, height,
>                                 imx214->fmt.width, imx214->fmt.height);
> @@ -930,7 +945,7 @@ static int imx214_get_regulators(struct device *dev, struct imx214 *imx214)
>                                        imx214->supplies);
>  }
>
> -static int imx214_parse_fwnode(struct device *dev)
> +static int imx214_parse_fwnode(struct device *dev, struct imx214 *imx214)
>  {
>         struct fwnode_handle *endpoint;
>         struct v4l2_fwnode_endpoint bus_cfg = {
> @@ -949,6 +964,14 @@ static int imx214_parse_fwnode(struct device *dev)
>                 goto done;
>         }
>
> +       /* Check the number of MIPI CSI2 data lanes */
> +       if (bus_cfg.bus.mipi_csi2.num_data_lanes != 4) {
> +               dev_err_probe(dev, -EINVAL,
> +                             "only 4 data lanes are currently supported\n");
> +               goto done;
> +       }

Until there is support for lanes !=4. I think is best if we just add
this check to imx214_parse_fwnode() and remove everything else from
this patch


> +       imx214->lanes = bus_cfg.bus.mipi_csi2.num_data_lanes;
> +
>         for (i = 0; i < bus_cfg.nr_of_link_frequencies; i++)
>                 if (bus_cfg.link_frequencies[i] == IMX214_DEFAULT_LINK_FREQ)
>                         break;
> @@ -973,14 +996,14 @@ static int imx214_probe(struct i2c_client *client)
>         struct imx214 *imx214;
>         int ret;
>
> -       ret = imx214_parse_fwnode(dev);
> -       if (ret)
> -               return ret;
> -
>         imx214 = devm_kzalloc(dev, sizeof(*imx214), GFP_KERNEL);
>         if (!imx214)
>                 return -ENOMEM;
>
> +       ret = imx214_parse_fwnode(dev, imx214);
> +       if (ret)
> +               return ret;
> +
>         imx214->dev = dev;
>
>         imx214->xclk = devm_clk_get(dev, NULL);
>
> --
> 2.46.0
>
>