Re: [PATCH net-next v2 8/8] net: pse-pd: Add PD692x0 PSE controller driver

[Köry Maincent]

On Thu, 21 Dec 2023 15:43:21 +0000
Mark Brown <broonie@xxxxxxxxxx> wrote:

> On Thu, Dec 21, 2023 at 04:36:10PM +0100, Köry Maincent wrote:
> > Mark Brown <broonie@xxxxxxxxxx> wrote:  
> 
> > > 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
> > 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.  
> 
> 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_regulator
driver which is a regulator consumer.
I don't know about other cases. Oleksij do you?

Regards,
-- 
Köry Maincent, Bootlin
Embedded Linux and kernel engineering
https://bootlin.com