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Date: Thu, 21 Dec 2023 17:10:00 +0100
From: =?UTF-8?B?S8O2cnk=?= Maincent <kory.maincent@bootlin.com>
To: Mark Brown <broonie@kernel.org>
Cc: Oleksij Rempel <o.rempel@pengutronix.de>, "David S. Miller"
 <davem@davemloft.net>, Eric Dumazet <edumazet@google.com>, Jakub Kicinski
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Subject: Re: [PATCH net-next v2 8/8] net: pse-pd: Add PD692x0 PSE controller
 driver
Message-ID: <20231221171000.45310167@kmaincent-XPS-13-7390>
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On Thu, 21 Dec 2023 15:43:21 +0000
Mark Brown <broonie@kernel.org> wrote:

> On Thu, Dec 21, 2023 at 04:36:10PM +0100, K=C3=B6ry Maincent wrote:
> > Mark Brown <broonie@kernel.org> wrote: =20
>=20
> > > OK...  I mean, if they're not using the regulator framework I'm not s=
ure
> > > it has much impact - there are plenty of internal regulators in devic=
es
> > > already so it wouldn't be *too* unusual other than the fact that AFAI=
CT
> > > this is somewhat split between devices within the subsystem?  Neither=
 of
> > > the messages was super clear. =20
>=20
> > PSE Power Interface (which is kind of the RJ45 in PSE world) have simil=
ar
> > functionalities as regulators. We wondered if registering a regulator f=
or
> > each PSE PI (RJ45 ports) is a good idea. The point is that the PSE
> > controller driver will be its own regulator consumer.
> > I can't find any example in Linux with such a case of a driver being a
> > provider and a consumer of its own regulator. This idea of a regulator
> > biting its own tail seems weird to me. Maybe it is better to implement =
the
> > PSE functionalities even if they are like the regulator functionalities=
. =20
>=20
> Is it at all plausible that a system (perhaps an embedded one) might use
> something other than PSE?

Do you mean to supply power to a RJ45 port?
This can be done with a simple regulator. In that case we use the pse_regul=
ator
driver which is a regulator consumer.
I don't know about other cases. Oleksij do you?

Regards,
--=20
K=C3=B6ry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com