Re: [PATCH v4 4/5] regulator: qcom: Add labibb driver

[Sumit Semwal]

On Wed, 17 Jun 2020 at 17:17, Mark Brown <broonie@xxxxxxxxxx> wrote:
>
> On Wed, Jun 17, 2020 at 05:12:35PM +0530, Sumit Semwal wrote:
>
> > I understand from a pure regulators' correctness point of view,
> > ENABLE_CTL should be the one checked there, so I can change the patch
> > as you suggested, but there seems to be some performance penalty
> > there.
>
> I thought the goal was to have the performance penalty to ensure that
> the regulator had actually started?
IMHO, with the poll_enabled_time mechanism added, we would not need to
wait for the full enabled_time time for the regulator to get enabled,
but we could poll (and potentially know earlier) if the regulator is
enabled.
The performance penalty I was talking, is about how should we check if
the regulator is really enabled or not - via reading the STATUS1
register, which seems to tell the status a bit faster, or via reading
the ENABLE_CTL register which we also use to enable/disable the
regulator, but which seems to be slower in updating the status.

>
> > > > The WARN_ON? This was suggested by Bjorn to catch the case where the
> > > > DT binding for a PMIC instantiates only one of the regulators.
>
> > > No, this whole loop - why this whole match and get child stuff?
>
> > This loop mechanism is what I saw in the other qcom regulators
> > upstream, so thought it was an acceptable way.
> > For the two children nodes, do you recommend another mechanism to get
> > and validate both nodes?
>
> I don't understand what you mean by "two children nodes" here?
The two 'lab' and 'ibb' regulator nodes that are part of the labibb node.

Best,
Sumit.