[PATCH 10/11] regulator: db8500: Add power domain regulators

[Ulf Hansson]

On Wed, Aug 19, 2026 at 3:30 PM Linus Walleij <linusw at kernel.org> wrote:
>
> On Wed, Jul 8, 2026 at 5:53 PM Ulf Hansson <ulf.hansson at oss.qualcomm.com> wrote:
>
> > On Thu, Jun 18, 2026 at 7:01 AM Linus Walleij <linusw at kernel.org> wrote:
> > >
> > > Add a DB8500 regulator driver for the VAPE and VSMPS2 compatibility nodes.
> > >
> > > Back the regulator enable state with the corresponding power domains.
> > >
> > > This is done for off-chip consumers: the corresponding voltage rails are
> > > routed out so they are used for powering different peripherals using
> > > these voltages as supplies.
> > >
> > > Assisted-by: Codex:gpt-5-5
> > > Signed-off-by: Linus Walleij <linusw at kernel.org>
> (...)
> > > @@ -673,6 +673,7 @@ db8500-prcmu-regulators {
> > >                                 // DB8500_REGULATOR_VAPE
> > >                                 db8500_vape_reg: db8500_vape {
> > >                                         regulator-always-on;
> > > +                                       power-domains = <&pm_domains DOMAIN_VAPE>;
> >
> > Hmm, isn't this the other way around? The power-domains node should
> > have a regulator supply?
>
> They probably have that, but that is not what this is about,
> it's the other way around.
>
> > We may even consider to skip to model the regulator altogether and
> > make the power domain operate directly on the prcmu instead.
>
> That is what the series tries to do, as a whole. Sorry if that was unclear...
>
> What we do in this patch is to deal with the fact that two of the power
> domains, when enabled, also turn on two external power rails outside
> of the SoC.
>
> Since external components such as I2C devices cannot really be
> claimed as "being inside a power domain" they take a regulator.

So with I2C devices you are not referring to the I2C controllers, right?

Are you saying that these external I2C devices consume the same
regulator as the power-domain DOMAIN_VAPE uses?

I thought these types of external devices in general use a different
voltage range. Moreover, do note that DOMAIN_VAPE also has
corresponding OPPs (performance states) that change the voltage level
based on the requested OPP. I am not sure an external I2C would be
able to cope with that.

>
> This is based on my understanding that power domains is an
> SoC-internal concept only, so there is a clear boundary if something
> outside of the SoC starts to use such an externalized power rail.
>
> All this regulator does is to make sure the corresponding power domain
> is enabled when the regulator is enabled.
>
> I will repost all the patches once v7.3-rc1 is out.
>
> Yours,
> Linus Walleij

Great! I really appreciate that you move this forward!

Kind regards
Uffe