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

From: Marco Felsch
Date: Tue Jan 07 2020 - 08:38:33 EST

On 20-01-07 13:09, Mark Brown wrote:
> 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.

Therefore I want to discuss the dt-binding documentation with you and
the others to get this done. Is the above description better to
understand the dt-binding?