Re: [PATCH v3] dt-bindings: net: nxp,sja1105: document spi-cpol/cpha

[Vladimir Oltean <olteanv@gmail.com>]

On Fri, Nov 04, 2022 at 01:15:57PM -0400, Krzysztof Kozlowski wrote:
> Some boards use SJA1105 Ethernet Switch with SPI CPHA, while ones with
> SJA1110 use SPI CPOL, so document this to fix dtbs_check warnings:
> 
>   arch/arm64/boot/dts/freescale/fsl-lx2160a-bluebox3.dtb: ethernet-switch@0: Unevaluated properties are not allowed ('spi-cpol' was unexpected)
> 
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> 
> ---
> 
> Changes since v2:
> 1. Add allOf:if:then, based on feedback from Vladimir.
> 
> Changes since v1:
> 1. Add also cpha
> ---
>  .../bindings/net/dsa/nxp,sja1105.yaml         | 27 ++++++++++++++++---
>  1 file changed, 23 insertions(+), 4 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
> index 1e26d876d146..ac66af3fdd82 100644
> --- a/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
> +++ b/Documentation/devicetree/bindings/net/dsa/nxp,sja1105.yaml
> @@ -12,10 +12,6 @@ description:
>    cs_sck_delay of 500ns. Ensuring that this SPI timing requirement is observed
>    depends on the SPI bus master driver.
>  
> -allOf:
> -  - $ref: "dsa.yaml#"
> -  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> -
>  maintainers:
>    - Vladimir Oltean <vladimir.oltean@nxp.com>
>  
> @@ -36,6 +32,9 @@ properties:
>    reg:
>      maxItems: 1
>  
> +  spi-cpha: true
> +  spi-cpol: true
> +

Why set to true only to set to false under allOf? Can't set to true in allOf?

>    # Optional container node for the 2 internal MDIO buses of the SJA1110
>    # (one for the internal 100base-T1 PHYs and the other for the single
>    # 100base-TX PHY). The "reg" property does not have physical significance.
> @@ -109,6 +108,26 @@ $defs:
>         1860, 1880, 1900, 1920, 1940, 1960, 1980, 2000, 2020, 2040, 2060, 2080,
>         2100, 2120, 2140, 2160, 2180, 2200, 2220, 2240, 2260]
>  
> +allOf:
> +  - $ref: dsa.yaml#
> +  - $ref: /schemas/spi/spi-peripheral-props.yaml#
> +  - if:
> +      properties:
> +        compatible:
> +          enum:
> +            - nxp,sja1105e
> +            - nxp,sja1105t
> +            - nxp,sja1105p
> +            - nxp,sja1105q
> +            - nxp,sja1105r
> +            - nxp,sja1105s
> +    then:
> +      properties:
> +        spi-cpol: false
> +    else:
> +      properties:
> +        spi-cpha: false
> +

The properties should probably also be 'required', since the hardware
doesn't work if they aren't present (omitting them changes the SPI mode
to 0).