Re: [PATCH net-next 1/3] dt-bindings: net: ethernet-phy: add property mac-series-termination-ohms

[Rob Herring <robh@kernel.org>]

On Fri, Mar 07, 2025 at 11:30:01AM +0100, Dimitri Fedrau wrote:
> Add property mac-series-termination-ohms in the device tree bindings for
> selecting the resistance value of the builtin series termination resistors
> of the PHY. Changing the resistance to an appropriate value can reduce
> signal reflections and therefore improve signal quality.
> 
> Signed-off-by: Dimitri Fedrau <dimitri.fedrau@liebherr.com>
> ---
>  Documentation/devicetree/bindings/net/ethernet-phy.yaml | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> index 824bbe4333b7ed95cc39737d3c334a20aa890f01..4a710315a83ccf15bfc210ae432ae988cf31e04c 100644
> --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> @@ -238,6 +238,11 @@ properties:
>        peak-to-peak specified in ANSI X3.263. When omitted, the PHYs default
>        will be left as is.
>  
> +  mac-series-termination-ohms:

A property of the MAC (or associated with it) should be in the MAC's 
node. Also, sounds like either either end could have a property. We 
already have similar properties in other cases: 'termination-ohms' for 
example. That appears to be for series term as well given a value of 
120ohms. 

Rob