Re: [PATCH] dt-bindings: can: renesas,rcar-canfd: Fix number of channels for R-Car V3U

[Rob Herring <robh@kernel.org>]

On Fri, Dec 02, 2022 at 09:22:11AM +0100, Geert Uytterhoeven wrote:
> According to the bindings, only two channels are supported.
> However, R-Car V3U supports eight, leading to "make dtbs" failures:
> 
>         arch/arm64/boot/dts/renesas/r8a779a0-falcon.dtb: can@e6660000: Unevaluated properties are not allowed ('channel2', 'channel3', 'channel4', 'channel5', 'channel6', 'channel7' were unexpected)
> 
> Update the number of channels to 8 on R-Car V3U.
> While at it, prevent adding more properties to the channel nodes, as
> they must contain no other properties than a status property.
> 
> Fixes: d6254d52d70de530 ("dt-bindings: can: renesas,rcar-canfd: Document r8a779a0 support")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
> ---
> Is there a way to express this using positive logic (i.e. default to 2
> channels, extend to more where needed)? R-Car V3H_2 (which is not yet
> supported) has 3 channels.

I think you'd need an if/elif/elif/else construct which is doable, but 
not pretty.

> Or perhaps the check should be dropped completely?

I'm fine with that.

Rob