Re: [PATCH] dt-bindings: display: panel: use spi-peripheral-props.yaml

[Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>]

On 04/10/2022 15:03, Laurent Pinchart wrote:
> Hi Krzysztof,
> 
> Thank you for the patch.
> 
> On Tue, Oct 04, 2022 at 02:09:07PM +0200, Krzysztof Kozlowski wrote:
>> For devices connectable by SPI bus (e.g. already using
>> "spi-max-frequency" property), reference the "spi-peripheral-props.yaml"
>> schema to allow using all SPI device properties, even these which device
>> bindings author did not tried yet.
> 
> Isn't this done implicitly by spi-controller.yaml ? SPI devices that are
> children of an SPI controller should match the patternProperties
> "^.*@[0-9a-f]+$" in that file, which has a $ref: spi-peripheral-props.yaml.
> Is there something I'm missing ?
> 

You are correct about one side of this - SPI controller bindings.
However these schemas here have clear: additional/unevaluatedProperties:
false, thus when they find DTS like:
panel@xxx {
  compatible = "one of these spi panels";
  ...
  spi-cs-high;
  spi-rx-delay-us = <50>;
  ... and some more from specific controllers
}

you will get errors, because the panel schema does not allow them.

The bindings were done (some time ago) in such way, that they require
that both SPI controller and SPI device reference spi-props.

Best regards,
Krzysztof