Re: [PATCH v5 01/16] dt-bindings: regulator: Document ROHM BD71282 regulator bindings

From: "Vaittinen, Matti" <Matti.Vaittinen@fi.rohmeurope.com>
To: "broonie@kernel.org" <broonie@kernel.org>
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Subject: Re: [PATCH v5 01/16] dt-bindings: regulator: Document ROHM BD71282 regulator bindings
Date: Tue, 10 Dec 2019 10:39:57 +0000	[thread overview]
Message-ID: <aea80c251dbafa8f2cd433eaf397a754812338d8.camel@fi.rohmeurope.com> (raw)
In-Reply-To: <20191204141433.GU1998@sirena.org.uk>

On Wed, 2019-12-04 at 14:14 +0000, Mark Brown wrote:
> On Wed, Dec 04, 2019 at 01:13:08PM +0000, Vaittinen, Matti wrote:
> 
> > I think I once again explained myself badly. There can be only one
> > group with 4 RUN states selected by combination of 2 GPIO lines.
> > bucks
> > 1,2,6 and 7 can each either be assigned into this one group or
> > controlled individually via I2C. But I doubt assigning only one of
> > the
> > bucks in this group is the typical use-case. What we would need
> > would
> 
> I don't think this is as unusual as you're thinking - the
> regulators people want to control quickly are usually the main
> CPU supply regulators and these often vary independently of
> anything else.

Hmm. I see your point. You might be correct. Allowing only one buck to
be assigned in 'run-level group' (to be controlled by GPIOs) would be
totally possible with current regulator API - and it might be useful
for scaling the CPU voltage. I appreciate your help and experience here
:) Implementing it would be also pretty simple, caching and controlling
the run-level voltages is already there in patch 12, I just should
restrict the group size to one buck. I will see how it works and also
ask if my colleagues know whether this is valuable with our current
customer's SOCs. Thanks a bunch!

Br,
	Matti Vaittinen