Re: [RFC net-next 1/3] dt-bindings: net: dsa: yt921x: Add Motorcomm YT921x switch support

[Krzysztof Kozlowski <krzk@kernel.org>]

On 14/08/2025 08:50, David Yang wrote:
> The Motorcomm YT921x series is a family of Ethernet switches with up to
> 8 internal GbE PHYs and up to 2 GMACs.
> 
> Signed-off-by: David Yang <mmyangfl@gmail.com>
> ---
>  .../bindings/net/dsa/motorcomm,yt921x.yaml    | 121 ++++++++++++++++++
>  1 file changed, 121 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/net/dsa/motorcomm,yt921x.yaml
> 
> diff --git a/Documentation/devicetree/bindings/net/dsa/motorcomm,yt921x.yaml b/Documentation/devicetree/bindings/net/dsa/motorcomm,yt921x.yaml
> new file mode 100644
> index 000000000000..2f0e4532e73e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/net/dsa/motorcomm,yt921x.yaml
> @@ -0,0 +1,121 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/net/dsa/motorcomm,yt921x.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Motorcomm YT921x Ethernet switch family
> +
> +maintainers:
> +  - David Yang <mmyangfl@gmail.com>
> +
> +description: |
> +  The Motorcomm YT921x series is a family of Ethernet switches with up to 8
> +  internal GbE PHYs and up to 2 GMACs, including YT9213NB, YT9214NB, YT9215RB,
> +  YT9215S, YT9215SC, YT9218N, YT9218MB.
> +
> +  For now, only YT9215 is supported.

Please describe complete hardware. Drivers are not relevant here and
binding cannot support anything, thus this feels like comment about drivers.

> +
> +properties:
> +  compatible:
> +    const: motorcomm,yt9215
> +
> +  reg:
> +    maxItems: 1
> +
> +  reset-gpios:
> +    description: Optional gpio specifier for a reset line

Drop comment, 100% redundant.

> +    maxItems: 1
> +
> +  motorcomm,switch-id:
> +    description: |
> +      When managed via mdio, hard-configured switch id to distinguish between
> +      multiple devices.

IDs are not allowed.

> +    enum: [0, 1, 2, 3]
> +    default: 0
> +
> +  mdio:
> +    $ref: /schemas/net/mdio.yaml#
> +    unevaluatedProperties: false
> +    description: MDIO bus for the internal GbE PHYs.
> +
> +  mdio-external:
> +    $ref: /schemas/net/mdio.yaml#
> +    unevaluatedProperties: false
> +    description: External MDIO bus.
> +
> +    properties:
> +      compatible:
> +        const: motorcomm,yt921x-mdio-external

Incomplete compatible... but also not needed in the first place.

> +
> +    required:
> +      - compatible
> +
> +allOf:
> +  - $ref: dsa.yaml#/$defs/ethernet-ports
> +
> +required:
> +  - compatible
> +  - reg
> +
> +unevaluatedProperties: false
> +
> +examples:
> +  - |
> +    mdio {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        switch@1d {
> +            compatible = "motorcomm,yt9215";
> +            reg = <0x1d>;
> +

Incomplete example. Where are all other properties?



Best regards,
Krzysztof