Re: strange dtbs_check error message regarding 8250_omap.yaml + serdev + gnss

[Rob Herring <robh@kernel.org>]

On Fri, Oct 1, 2021 at 3:22 AM Andreas Kemnade <andreas@kemnade.info> wrote:
>
> Hi,
>
> while doing some make dtbs_check cleanup I came across this message:
>
> /home/andi/kernel/linux/arch/arm/boot/dts/omap3-gta04a4.dt.yaml: serial@4806c000: 'gnss' does not match any of the regexes: 'pinctrl-[0-9]+'
>         From schema: /home/andi/kernel/linux/Documentation/devicetree/bindings/serial/8250_omap.yaml
>
> the corresponding snippet is this one:
>
> &uart2 {
>         pinctrl-names = "default";
>         pinctrl-0 = <&uart2_pins>;
>         gnss: gnss {
>                 compatible = "wi2wi,w2sg0004";
>                 pinctrl-names = "default";
>                 pinctrl-0 = <&gps_pins>;
>                 sirf,onoff-gpios = <&gpio5 17 GPIO_ACTIVE_HIGH>;
>                 lna-supply = <&vsim>;
>                 vcc-supply = <&ldo_3v3>;
>         };
> };
>
>
> I see a pattern for serdev objects in
> Documentation/devicetree/bindings/serial/serial.yaml
>
> patternProperties:
>   ".*":
>     if:
>       type: object
>     then:
>       description:
>         Serial attached devices shall be a child node of the host UART device
>         the slave device is attached to. It is expected that the attached
>         device is the only child node of the UART device. The slave device node
>         name shall reflect the generic type of device for the node.
>
>
> so I would say, everything is allowed. serial.yaml is referenced by
> 8250_omap.yaml. So what is the problem here?

8250_omap.yaml probably has 'additionalProperties: false'. The problem
with additionalProperties is it can't see into the $ref to
serial.yaml. The fix is to use 'unevaluatedProperties' instead. Note
that it currently is a nop, so don't expect to get any failures.
Support for unevaluatedProperties was just released in jsonschema
yesterday, so dtschema will support it very soon.

Rob