Re: [PATCH v4 3/4] ARM: dts: imx6ull-colibri: Set LCDIF bus-width

[Luca Ceresoli]

Hi Francesco,

> The lcd DPI interface on colibri imx6ull uses a 18-bit width bus, set
> the bus-width property accordingly.
>
> Signed-off-by: Francesco Dolcini <francesco.dolcini@xxxxxxxxxxx>
>
> diff --git a/arch/arm/boot/dts/nxp/imx/imx6ull-colibri.dtsi b/arch/arm/boot/dts/nxp/imx/imx6ull-colibri.dtsi
> index ec3c1e7301f4..1eb1cf2d7395 100644
> --- a/arch/arm/boot/dts/nxp/imx/imx6ull-colibri.dtsi
> +++ b/arch/arm/boot/dts/nxp/imx/imx6ull-colibri.dtsi
> @@ -229,6 +229,7 @@ &lcdif {
>
>  	port {
>  		lcdif_out: endpoint {
> +			bus-width = <18>;

I don't know the hardware in detail, but the datasheet [0] mentions 16, 18
and 24 bits, and says "Up to 24-bit color (18-bit recommended)". More
details in ection 5.6.1.

This patch would force 18 bits, but "recommended" suggests 24 bits makes
sense in some cases, no?

Can you elaborate on this?

Same for patch 4.

[0] https://docs.toradex.com/104446-colibri-arm-som-imx6ull-datasheet.pdf

Luca

-- 
Luca Ceresoli, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com