Re: [PATCH net-next v3 1/7] net: ethtool: pse-pd: Expand C33 PSE status with class, power and extended state

From: Oleksij Rempel
Date: Tue Jun 25 2024 - 06:34:14 EST


Hi Köry,

On Tue, Jun 25, 2024 at 11:18:35AM +0200, Kory Maincent wrote:
> Hello Oleksij,
>
> On Mon, 17 Jun 2024 21:55:25 +0200
> Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> wrote:
>
> >
> > > > The difference between open and underload is probably:
> > > > - open: Iport = 0, detection state
> > > > - underload: Iport < Imin (or Ihold?), Iport can be 0. related to
> > > > powered/MPS state.
> > >
> > > Should I put it under MPS substate then?
> >
> > If my understand is correct, then yes. Can you test it? Do you have PD
> > with adjustable load?
>
> In fact I can't test it, I have a splitter and an adjustable load, not a
> splitter that can adjust it's own load. So I can't decrease the load of the
> splitter itself and reach this error condition.

Hm.. how about this setup:
------>>-----x--------->>----
PSE |-load splitter
------>>-----x--------->>----

Attach the load directly to the ethernet line after PSE did
classification with splitter. Then remove splitter. As long as load is
high enough, PSE will not turn the port off. Then reduce load until it drops
below the threshold.

Regards,
Oleksij
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