Re: [PATCH v3 2/5] dt-bindings: net: qca,ar803x: Add IPQ5018 Internal GE PHY support

[Rob Herring <robh@kernel.org>]

On Mon, Jun 02, 2025 at 01:53:14PM +0400, George Moussalem wrote:
> Document the IPQ5018 Internal Gigabit Ethernet PHY found in the IPQ5018
> SoC. Its output pins provide an MDI interface to either an external
> switch in a PHY to PHY link scenario or is directly attached to an RJ45
> connector.
> 
> The PHY supports 10/100/1000 mbps link modes, CDT, auto-negotiation and
> 802.3az EEE.
> 
> For operation, the LDO controller found in the IPQ5018 SoC for which
> there is provision in the mdio-4019 driver.
> 
> Two common archictures across IPQ5018 boards are:
> 1. IPQ5018 PHY --> MDI --> RJ45 connector
> 2. IPQ5018 PHY --> MDI --> External PHY
> In a phy to phy architecture, the DAC needs to be configured to
> accommodate for the short cable length. As such, add an optional boolean
> property so the driver sets preset DAC register values accordingly.
> 
> Signed-off-by: George Moussalem <george.moussalem@outlook.com>
> ---
>  .../devicetree/bindings/net/qca,ar803x.yaml        | 39 ++++++++++++++++++++++
>  1 file changed, 39 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/qca,ar803x.yaml b/Documentation/devicetree/bindings/net/qca,ar803x.yaml
> index 3acd09f0da863137f8a05e435a1fd28a536c2acd..fce167412896edbf49371129e3e7e87312eee051 100644
> --- a/Documentation/devicetree/bindings/net/qca,ar803x.yaml
> +++ b/Documentation/devicetree/bindings/net/qca,ar803x.yaml
> @@ -16,8 +16,32 @@ description: |
>  
>  allOf:
>    - $ref: ethernet-phy.yaml#
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - ethernet-phy-id004d.d0c0
> +
> +    then:
> +      properties:
> +        reg:
> +          const: 7  # This PHY is always at MDIO address 7 in the IPQ5018 SoC

blank line

> +        resets:
> +          items:
> +            - description:
> +                GE PHY MISC reset which triggers a reset across MDC, DSP, RX, and TX lines.

blank line

> +        qcom,dac-preset-short-cable:
> +          description:
> +            Set if this phy is connected to another phy to adjust the values for
> +            MDAC and EDAC to adjust amplitude, bias current settings, and error
> +            detection and correction algorithm to accommodate for short cable length.
> +            If not set, it is assumed the MDI output pins of this PHY are directly
> +            connected to an RJ45 connector and default DAC values will be used.
> +          type: boolean
>  
>  properties:
> +

Drop

But this schema is broken. There's no way for it to be applied to a node 
because there is no compatible defined in this schema nor a 'select'. 
You can introduce an error and see (e.g. 'qcom,dac-preset-short-cable = 
"foo";'). Really, any phy using these properties should have a specific 
compatible defined here.

>    qca,clk-out-frequency:
>      description: Clock output frequency in Hertz.
>      $ref: /schemas/types.yaml#/definitions/uint32
> @@ -132,3 +156,18 @@ examples:
>              };
>          };
>      };
> +  - |
> +    #include <dt-bindings/reset/qcom,gcc-ipq5018.h>
> +
> +    mdio {
> +        #address-cells = <1>;
> +        #size-cells = <0>;
> +
> +        /* add alias to set qcom,dac-preset-short-cable on boards that need it */
> +        ge_phy: ethernet-phy@7 {
> +            compatible = "ethernet-phy-id004d.d0c0";
> +            reg = <7>;
> +
> +            resets = <&gcc GCC_GEPHY_MISC_ARES>;
> +        };
> +    };
> 
> -- 
> 2.49.0
>