Subject: Re: [PATCH 2/2] dt-bindings: net: add new property st,ext-phyclk in documentation for stm32

From: Rob Herring <[email-masked]>
Date: Mon, 4 Mar 2024 10:24:43 -0600

On Thu, Feb 29, 2024 at 02:47:24PM +0100, Christophe Roullier wrote:
> Add property st,ext-phyclk to manage cases when PHY have no cristal/quartz
> This property can be used with RMII phy without cristal 50Mhz and when we
> want to select RCC clock instead of ETH_REF_CLK
> Can be used also with RGMII phy with no cristal and we select RCC clock
> instead of ETH_CLK125
> This new property replace st,eth-clk-sel and st,eth-ref-clk-sel

That is obvious from the diff. What is not obvious is why we need a new 
property and what is the problem with the existing ones.

> 
> Signed-off-by: Christophe Roullier <[email-masked]>
> ---
>  Documentation/devicetree/bindings/net/stm32-dwmac.yaml | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/stm32-dwmac.yaml b/Documentation/devicetree/bindings/net/stm32-dwmac.yaml
> index 80937b28fa046..fda23c07c1cad 100644
> --- a/Documentation/devicetree/bindings/net/stm32-dwmac.yaml
> +++ b/Documentation/devicetree/bindings/net/stm32-dwmac.yaml
> @@ -85,12 +85,21 @@ properties:
>    phy-supply:
>      description: PHY regulator
>  
> +  st,ext-phyclk:
> +    description:
> +      set this property in RMII mode when you have PHY without crystal 50MHz and want to
> +      select RCC clock instead of ETH_REF_CLK. OR in RGMII mode when you want to select
> +      RCC clock instead of ETH_CLK125.
> +    type: boolean
> +
>    st,eth-clk-sel:
> +    deprecated: true
>      description:
>        set this property in RGMII PHY when you want to select RCC clock instead of ETH_CLK125.
>      type: boolean
>  
>    st,eth-ref-clk-sel:
> +    deprecated: true
>      description:
>        set this property in RMII mode when you have PHY without crystal 50MHz and want to
>        select RCC clock instead of ETH_REF_CLK.
> -- 
> 2.25.1
>