Re: [PATCH v3 06/12] media: i2c: imx214: Check number of lanes from device tree

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Hi André,

On Sat, Dec 07, 2024 at 09:47:55PM +0100, André Apitzsch via B4 Relay 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 | 16 ++++++++++++++--
>  1 file changed, 14 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/media/i2c/imx214.c b/drivers/media/i2c/imx214.c
> index 07926f7257877155548f7bcf0e7ee80037b4ce6c..f1c72db0775eaf4810f762e8798d301c5ad9923c 100644
> --- a/drivers/media/i2c/imx214.c
> +++ b/drivers/media/i2c/imx214.c
> @@ -199,7 +199,6 @@ struct imx214 {
>  
>  /*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 +271,6 @@ 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 },
> @@ -788,6 +786,13 @@ static int imx214_start_streaming(struct imx214 *imx214)
>  		return ret;
>  	}
>  
> +	ret = cci_write(imx214->regmap, IMX214_REG_CSI_LANE_MODE,
> +			IMX214_CSI_4_LANE_MODE, NULL);
> +	if (ret) {
> +		dev_err(imx214->dev, "%s failed to configure lanes\n", __func__);

You can drop the function name here.

> +		return ret;
> +	}
> +
>  	ret = cci_multi_reg_write(imx214->regmap, imx214->cur_mode->reg_table,
>  				  imx214->cur_mode->num_of_regs, NULL);
>  	if (ret < 0) {
> @@ -948,6 +953,13 @@ 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) {
> +		ret = dev_err_probe(dev, -EINVAL,
> +				    "only 4 data lanes are currently supported\n");
> +		goto done;
> +	}
> +
>  	for (i = 0; i < bus_cfg.nr_of_link_frequencies; i++)
>  		if (bus_cfg.link_frequencies[i] == IMX214_DEFAULT_LINK_FREQ)
>  			break;
> 

-- 
Sakari Ailus