Re: [PATCH net-next v2 0/3] net: mdio: support dynamic OF device changes

[James Hilliard]

On Tue, Aug 4, 2026 at 12:57 PM Andrew Lunn <andrew@xxxxxxx> wrote:
>
> On Tue, Aug 04, 2026 at 09:10:30AM -0600, James Hilliard wrote:
> > On Tue, Aug 4, 2026 at 6:54 AM Andrew Lunn <andrew@xxxxxxx> wrote:
> > >
> > > > > If this was a hat on top of a SBC, with an EEPROM indicating what the
> > > > > hat was, then maybe DT overlays would make sense. But from what you
> > > > > have said, this is a fixed PCB design, nothing hot/cold plugable.
> > > >
> > > > Some H616/H618 boards have the ethernet port on an expansion board:
> > > > http://www.orangepi.org/html/hardWare/computerAndMicrocontrollers/details/2W-expansion-board.html
> > >
> > > I don't see a list of pins which go across the connector. Does the
> > > MDIO bus go to the expansion board? Is the PHY on the expansion
> > > board. It all looks passive to me.
> >
> > Pins are listed under "24Pin expansion board interface pin description":
> > https://orangepi.net/wp-content/uploads/2023/10/OrangePi_Zero2w_H618_User-Manual_v1.1.pdf
>
> So just the lines after the PHY, basically the UTP lines without the
> twist.
>
> So please stop wasting my time by making invalid points.

I'm confused how this is an invalid point.

Presumably one may want to use OF_DYNAMIC to dynamically
enable the PHY only when the expansion board is installed.

Whether or not the MDIO bus is wired to the expansion board or
physically integrated into the SoC doesn't seem like it would make
a difference in regards to whether or not one would want to dynamically
enable the PHY using OF_DYNAMIC as that decision would presumably
be made based on the actual configured hardware setup. If the PHY is
not physically connected to an ethernet port then presumably it should
remain disabled due to that being a non-functional hardware configuration.

Or am I missing something here?

>
>    Andrew