[PATCH v4 11/15] drm: renesas: rz-du: mipi_dsi: Add feature flag for 16BPP support

[Biju Das]

Hi Prabhakar,

Thanks for the patch.

> -----Original Message-----
> From: Prabhakar <prabhakar.csengg at gmail.com>
> Sent: 30 April 2025 21:41
> Subject: [PATCH v4 11/15] drm: renesas: rz-du: mipi_dsi: Add feature flag for 16BPP support
> 
> From: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>
> 
> Introduce the `RZ_MIPI_DSI_FEATURE_16BPP` flag in `rzg2l_mipi_dsi_hw_info` to indicate support for
> 16BPP pixel formats. The RZ/V2H(P) SoC supports 16BPP, whereas this feature is missing on the RZ/G2L
> SoC.
> 
> Update the `mipi_dsi_host_attach()` function to check this flag before allowing 16BPP formats. If the
> SoC does not support 16BPP, return an error to prevent incorrect format selection.
> 
> This change enables finer-grained format support control for different SoC variants.
> 
> Co-developed-by: Fabrizio Castro <fabrizio.castro.jz at renesas.com>
> Signed-off-by: Fabrizio Castro <fabrizio.castro.jz at renesas.com>
> Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj at bp.renesas.com>

Reviewed-by: Biju Das <biju.das.jz at bp.renesas.com>

Cheers,
Biju

> ---
> v3->v4:
> - No changes
> 
> v2->v3:
> - No changes
> 
> v1->v2:
> - Renamed RZ_MIPI_DSI_FEATURE_16BPP
> ---
>  drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-
> du/rzg2l_mipi_dsi.c
> index a4c0dbae4a46..8c7384b95411 100644
> --- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> +++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
> @@ -29,6 +29,7 @@
>  #include "rzg2l_mipi_dsi_regs.h"
> 
>  #define RZ_MIPI_DSI_FEATURE_DPHY_RST	BIT(0)
> +#define RZ_MIPI_DSI_FEATURE_16BPP	BIT(1)
> 
>  struct rzg2l_mipi_dsi;
> 
> @@ -643,8 +644,16 @@ static int rzg2l_mipi_dsi_host_attach(struct mipi_dsi_host *host,
> 
>  	switch (mipi_dsi_pixel_format_to_bpp(device->format)) {
>  	case 24:
> +		break;
>  	case 18:
>  		break;
> +	case 16:
> +		if (!(dsi->info->features & RZ_MIPI_DSI_FEATURE_16BPP)) {
> +			dev_err(dsi->dev, "Unsupported format 0x%04x\n",
> +				device->format);
> +			return -EINVAL;
> +		}
> +		break;
>  	default:
>  		dev_err(dsi->dev, "Unsupported format 0x%04x\n", device->format);
>  		return -EINVAL;
> --
> 2.49.0