Re: [PATCH net-next 2/8] dt-bindings: net: lan9645x: add LAN9645X switch bindings

[Conor Dooley <conor@kernel.org>]

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On Tue, Mar 03, 2026 at 03:18:45PM +0100, Andrew Lunn wrote:
> > +        properties:
> > +          microchip,led-drive-mode:
> > +            $ref: /schemas/types.yaml#/definitions/uint32
> > +            description: |
> > +              Set the LED drive mode for the copper PHY associated with
> > +              this port.
> > +
> > +                0 - LED1 and LED2 in open-drain mode
> > +                1 - LED1 in active drive mode (can be used for single-LED
> > +                    configurations requiring active drive)
> > +                2 - Reserved
> > +                3 - LED1 and LED2 in active drive mode
> > +            minimum: 0
> > +            maximum: 3
> 
> I doubt the DT Maintainers will accept that. This looks a lot like a
> value you write into a register. How are active drive and open-drain
> described in other DT bindings? Is there something you can reuse?

I had a quick look and I didn't see anything really that stood out to me
that would be a drop-in replacement.
I also tried looking in the datasheet for more information on these
modes, but I couldn't see anything obvious. For example, there were zero
hits for "drain" in either LAN9645xS or LAN9645xF datasheets.

That said, yea you're right about DT maintainer feelings about it.
There's a couple things I could suggest, but I'd like to know about what
mode 1 means for LED2 first. If there's actually nothing similar, what
about representing each led with a child node and having open-drain be
the default with a property in the child for active-drive?

> 
> For 1, what happens to LED2? Not used at all?
> 
>     Andrew

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