Subject: Re: [PATCH v3 1/2] dt-bindings: net: dsa: add new mdio property

From: Rob Herring <[email-masked]>
Date: Thu, 24 Feb 2022 14:11:55 -0600

On Mon, Feb 21, 2022 at 05:01:02PM -0300, Luiz Angelo Daros de Luca wrote:
> The optional mdio property will be used by dsa switch to configure
> slave_mii_bus when the driver does not allocate it during setup.
> 
> Some drivers already offer/require a similar property but, in some
> cases, they rely on a compatible string to identify the mdio bus node.

That case will fail with this change. It precludes any binding 
referencing dsa.yaml from defining a 'mdio' node with properties other 
than what mdio.yaml defines.

The rule is becoming any common schema should not define more than one 
level of nodes if those levels can be extended.

> Each subdriver might decide to keep existing approach or migrate to this
> new common property.
> 
> Signed-off-by: Luiz Angelo Daros de Luca <[email-masked]>
> ---
>  Documentation/devicetree/bindings/net/dsa/dsa.yaml | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/dsa/dsa.yaml b/Documentation/devicetree/bindings/net/dsa/dsa.yaml
> index b9d48e357e77..f9aa09052785 100644
> --- a/Documentation/devicetree/bindings/net/dsa/dsa.yaml
> +++ b/Documentation/devicetree/bindings/net/dsa/dsa.yaml
> @@ -32,6 +32,12 @@ properties:
>        (single device hanging off a CPU port) must not specify this property
>      $ref: /schemas/types.yaml#/definitions/uint32-array
>  
> +  mdio:
> +    unevaluatedProperties: false
> +    description:
> +      Container of PHY and devices on the switches MDIO bus.
> +    $ref: /schemas/net/mdio.yaml#
> +
>  patternProperties:
>    "^(ethernet-)?ports$":
>      type: object
> -- 
> 2.35.1
> 
>