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Date:   Thu, 5 Nov 2020 16:10:09 +0530
From:   Viresh Kumar <viresh.kumar@linaro.org>
To:     Ulf Hansson <ulf.hansson@linaro.org>
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Subject: Re: [PATCH v1 00/30] Introduce core voltage scaling for NVIDIA
 Tegra20/30 SoCs
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On 05-11-20, 11:34, Ulf Hansson wrote:
> I am not objecting about scaling the voltage through a regulator,
> that's fine to me. However, encoding a power domain as a regulator
> (even if it may seem like a regulator) isn't. Well, unless Mark Brown
> has changed his mind about this.
>
> In this case, it seems like the regulator supply belongs in the
> description of the power domain provider.

Okay, I wasn't sure if it is a power domain or a regulator here. Btw,
how do we identify if it is a power domain or a regulator ?

> > In case of Qcom earlier (when we added the performance-state stuff),
> > the eventual hardware was out of kernel's control and we didn't wanted
> > (allowed) to model it as a virtual regulator just to pass the votes to
> > the RPM. And so we did what we did.
> >
> > But if the hardware (where the voltage is required to be changed) is
> > indeed a regulator and is modeled as one, then what Dmitry has done
> > looks okay. i.e. add a supply in the device's node and microvolt
> > property in the DT entries.
> 
> I guess I haven't paid enough attention how power domain regulators
> are being described then. I was under the impression that the CPUfreq
> case was a bit specific - and we had legacy bindings to stick with.
> 
> Can you point me to some other existing examples of where power domain
> regulators are specified as a regulator in each device's node?

No, I thought it is a regulator here and not a power domain.

-- 
viresh