On Fri, Oct 23, 2020 at 07:45:37PM +0200, Paul Kocialkowski wrote:
> Bits related to the interface data width do not have any effect when
> the CSI controller is taking input from the MIPI CSI-2 controller.

I guess it would be clearer to mention that the data width is only
applicable for parallel here.

> In prevision of adding support for this case, set these bits
> conditionally so there is no ambiguity.
> 
> Co-developed-by: Kévin L'hôpital <kevin.lhopital@bootlin.com>
> Signed-off-by: Kévin L'hôpital <kevin.lhopital@bootlin.com>
> Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
> ---
>  .../platform/sunxi/sun6i-csi/sun6i_csi.c      | 42 +++++++++++--------
>  1 file changed, 25 insertions(+), 17 deletions(-)
> 
> diff --git a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
> index 5d2389a5cd17..a876a05ea3c7 100644
> --- a/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
> +++ b/drivers/media/platform/sunxi/sun6i-csi/sun6i_csi.c
> @@ -378,8 +378,13 @@ static void sun6i_csi_setup_bus(struct sun6i_csi_dev *sdev)
>  	unsigned char bus_width;
>  	u32 flags;
>  	u32 cfg;
> +	bool input_parallel = false;
>  	bool input_interlaced = false;
>  
> +	if (endpoint->bus_type == V4L2_MBUS_PARALLEL ||
> +	    endpoint->bus_type == V4L2_MBUS_BT656)
> +		input_parallel = true;
> +
>  	if (csi->config.field == V4L2_FIELD_INTERLACED
>  	    || csi->config.field == V4L2_FIELD_INTERLACED_TB
>  	    || csi->config.field == V4L2_FIELD_INTERLACED_BT)
> @@ -395,6 +400,26 @@ static void sun6i_csi_setup_bus(struct sun6i_csi_dev *sdev)
>  		 CSI_IF_CFG_HREF_POL_MASK | CSI_IF_CFG_FIELD_MASK |
>  		 CSI_IF_CFG_SRC_TYPE_MASK);
>  
> +	if (input_parallel) {
> +		switch (bus_width) {
> +		case 8:
> +			cfg |= CSI_IF_CFG_IF_DATA_WIDTH_8BIT;
> +			break;
> +		case 10:
> +			cfg |= CSI_IF_CFG_IF_DATA_WIDTH_10BIT;
> +			break;
> +		case 12:
> +			cfg |= CSI_IF_CFG_IF_DATA_WIDTH_12BIT;
> +			break;
> +		case 16: /* No need to configure DATA_WIDTH for 16bit */
> +			break;
> +		default:
> +			dev_warn(sdev->dev, "Unsupported bus width: %u\n",
> +				 bus_width);
> +			break;
> +		}
> +	}
> +
>  	if (input_interlaced)
>  		cfg |= CSI_IF_CFG_SRC_TYPE_INTERLACED;
>  	else
> @@ -440,23 +465,6 @@ static void sun6i_csi_setup_bus(struct sun6i_csi_dev *sdev)
>  		break;
>  	}
>  
> -	switch (bus_width) {
> -	case 8:
> -		cfg |= CSI_IF_CFG_IF_DATA_WIDTH_8BIT;
> -		break;
> -	case 10:
> -		cfg |= CSI_IF_CFG_IF_DATA_WIDTH_10BIT;
> -		break;
> -	case 12:
> -		cfg |= CSI_IF_CFG_IF_DATA_WIDTH_12BIT;
> -		break;
> -	case 16: /* No need to configure DATA_WIDTH for 16bit */
> -		break;
> -	default:
> -		dev_warn(sdev->dev, "Unsupported bus width: %u\n", bus_width);
> -		break;
> -	}
> -

Is there any reason to move it around?

Maxime