Re: [PATCH v4 4/4] regulator: Prevent falling too fast

From: Mark Brown
Date: Tue Dec 13 2016 - 12:19:26 EST

On Mon, Dec 12, 2016 at 01:15:02PM -0800, Matthias Kaehlcke wrote:
> El Fri, Oct 28, 2016 at 07:15:21PM +0100 Mark Brown ha dit:
> > On Mon, Sep 26, 2016 at 10:41:59AM -0700, Doug Anderson wrote:

> > What you're describing to me is a discrete DCDC that has an input
> > voltage that sets the output voltage which happens to be set with a PWM.

> I experimented a bit with this. Besides the question of how to model
> the passives I wonder how the two regulators would interact. The
> correct thing seems to be to specify the input regulator as a supply
> of the DCDC. dcdc->set_voltage breaks down a voltage transition into

No, not unless the prior descriptions of the hardware have been wildly
inaccurate - my understanding had been that the DCDC was a normal DCDC
with an analogue input intended to be biased to set the output voltage
(presumably in terms of a full rail supply) and that the PWM had been
connected to this analogue input. If the PWM is supplying the DCDC then
the hardware design just seems bizzare, I can't see how this would even

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