Subject: Re: [PATCH v3 3/6] dt-bindings: mfd: da9062: add regulator voltage selection documentation

From: Mark Brown <[email-masked]>
Date: Tue, 7 Jan 2020 13:09:11 +0000

On Tue, Jan 07, 2020 at 09:36:54AM +0100, Marco Felsch wrote:
> On 19-12-17 12:58, Mark Brown wrote:

> > This doesn't say anything about how the GPIO input is expected to be
> > controlled, for voltage setting any runtime control would need to be
> > done by the driver and it sounds like that's all that can be controlled.
> > The way this reads I'd expect one use of this to be for fast voltage
> > setting for example (you could even combine that with suspend sequencing
> > using the internal sequencer if you mux back to the sequencer during
> > suspend).

> The input signal is routed trough the da9062 gpio block to the
> regualtors. You can't set any voltage value using a gpio instead you
> decide which voltage setting is applied. The voltage values for
> runtime/suspend comes from the dt-data. No it's not just a fast
> switching option imagine the system suspend case where the cpu and soc
> voltage can be reduced to a very low value. Older soc's like the imx6
> signaling this state by a hard wired gpio line because the soc and
> cpu cores don't work properly on such low voltage values. This is
> my use case and I can't use the sequencer.

My point is that I can't tell any of this from the description.
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