Re: [RFC 1/9] dt-bindings: display: renesas,cmm: Add R-Car CMM documentation

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Jacopo,

Thank you for the patch.

On Wed, May 08, 2019 at 07:34:20PM +0200, Jacopo Mondi wrote:
> Add device tree bindings documentation for the Renesas R-Car Display
> Unit Color Management Module.
> 
> CMM is the image enhancement module available on each R-Car DU video
> channel.

Not on all of them, V3M and V3H don't include a CMM module.

> Signed-off-by: Jacopo Mondi <jacopo+renesas@jmondi.org>
> ---
>  .../bindings/display/renesas,cmm.txt          | 24 +++++++++++++++++++
>  1 file changed, 24 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/renesas,cmm.txt
> 
> diff --git a/Documentation/devicetree/bindings/display/renesas,cmm.txt b/Documentation/devicetree/bindings/display/renesas,cmm.txt
> new file mode 100644
> index 000000000000..d7674417edb4
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/renesas,cmm.txt
> @@ -0,0 +1,24 @@
> +* Renesas R-Car Color Management Unit (CMM)

It's called Color Management Module in the documentation (hence the CMM
abbreviation)

> +
> +Renesas R-Car image enhancement module connected to R-Car DU video channels.
> +
> +Required properties:
> + - compatible: shall be:
> +   - "renesas,cmm"

There's a CMM in R-Car Gen2 with a different feature set, so I think you
need at least two compatible strings. As far as I can tell SoC-specific
compatible strings are required.

> +
> + - reg: the address base and length of the memory area where CMM control
> +   registers are mapped to.
> +
> + - clocks: phandle and clock-specifier pair to the CMM functional clock
> +   supplier.
> +
> +Example:
> +--------
> +
> +	cmm0: cmm@fea40000 {
> +		compatible = "renesas,cmm";
> +		reg = <0 0xfea40000 0 0x1000>;
> +		power-domains = <&sysc R8A7796_PD_ALWAYS_ON>;
> +		clocks = <&cpg CPG_MOD 711>;
> +		resets = <&cpg 711>;
> +	};

-- 
Regards,

Laurent Pinchart