Subject: Re: [PATCH net-next v2 1/3] dt-bindings: net: ethernet-phy: add property tx-amplitude-100base-tx-gain-milli

From: Dimitri Fedrau <[email-masked]>
Date: Fri, 24 Jan 2025 07:36:50 +0100

Hi Krzysztof,

Am Tue, Jan 21, 2025 at 11:17:34AM +0100 schrieb Krzysztof Kozlowski:
> On Mon, Jan 20, 2025 at 02:50:21PM +0100, Dimitri Fedrau wrote:
> > Add property tx-amplitude-100base-tx-gain-milli in the device tree bindings
> > for configuring the tx amplitude of 100BASE-TX PHYs. Modifying it can be
> > necessary to compensate losses on the PCB and connector, so the voltages
> > measured on the RJ45 pins are conforming.
> > 
> > Signed-off-by: Dimitri Fedrau <[email-masked]>
> > ---
> >  Documentation/devicetree/bindings/net/ethernet-phy.yaml | 8 ++++++++
> >  1 file changed, 8 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/net/ethernet-phy.yaml b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> > index 2c71454ae8e362e7032e44712949e12da6826070..ce65413410c2343a3525e746e72b6c6c8bb120d0 100644
> > --- a/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> > +++ b/Documentation/devicetree/bindings/net/ethernet-phy.yaml
> > @@ -232,6 +232,14 @@ properties:
> >        PHY's that have configurable TX internal delays. If this property is
> >        present then the PHY applies the TX delay.
> >  
> > +  tx-amplitude-100base-tx-gain-milli:
> > +    description: |
> > +      Transmit amplitude gain applied (in milli units) for 100BASE-TX. When
> 
> milli is unit prefix, not the unit. What is the unit? percentage? basis
> point?
> 
I think it would be better to switch to percentage. Resolution should be
fine. I would switch to:
tx-amplitude-100base-tx-percent

> > +      omitted, the PHYs default will be left as is. If not present, default to
> > +      1000 (no actual gain applied).
> 
> Don't repeat constraints in free form text.
> 
Will fix this.

Best regards,
Dimitri