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Date: Thu, 21 Dec 2023 16:36:10 +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
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On Tue, 5 Dec 2023 15:57:28 +0000
Mark Brown <broonie@kernel.org> wrote:

> On Tue, Dec 05, 2023 at 03:02:03PM +0100, Oleksij Rempel wrote:
> > On Tue, Dec 05, 2023 at 12:55:18PM +0000, Mark Brown wrote: =20
> > > On Tue, Dec 05, 2023 at 07:45:27AM +0100, Oleksij Rempel wrote: =20
>=20
> > > > CC regulator devs here too. =20
>=20
> > > Again, I'm not sure what if any question there is? =20
>=20
> > PSE is kind of PMIC for Ethernet ports. I assume, it is good to let you
> > know at least about existence drivers. =20
>=20
> OK...  I mean, if they're not using the regulator framework I'm not sure
> it has much impact - there are plenty of internal regulators in devices
> already so it wouldn't be *too* unusual other than the fact that AFAICT
> this is somewhat split between devices within the subsystem?  Neither of
> the messages was super clear.

PSE Power Interface (which is kind of the RJ45 in PSE world) have similar
functionalities as regulators. We wondered if registering a regulator for
each PSE PI (RJ45 ports) is a good idea. The point is that the PSE controll=
er
driver will be its own regulator consumer.
I can't find any example in Linux with such a case of a driver being a prov=
ider
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 functionali=
ties
even if they are like the regulator functionalities.

What do you think?

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