Re: [PATCH 3/6] net: stmmac: sun8i: Use devm_regulator_get for PHY regulator

From: OndÅej Jirman
Date: Tue Aug 20 2019 - 12:20:32 EST


Hi,

On Tue, Aug 20, 2019 at 05:57:44PM +0200, Andrew Lunn wrote:
> On Tue, Aug 20, 2019 at 05:47:14PM +0200, OndÅej Jirman wrote:
> > Hi Andrew,
> >
> > On Tue, Aug 20, 2019 at 05:39:39PM +0200, Andrew Lunn wrote:
> > > On Tue, Aug 20, 2019 at 04:53:40PM +0200, megous@xxxxxxxxxx wrote:
> > > > From: Ondrej Jirman <megous@xxxxxxxxxx>
> > > >
> > > > Use devm_regulator_get instead of devm_regulator_get_optional and rely
> > > > on dummy supply. This avoids NULL checks before regulator_enable/disable
> > > > calls.
> > >
> > > Hi Ondrej
> > >
> > > What do you mean by a dummy supply? I'm just trying to make sure you
> > > are not breaking backwards compatibility.
> >
> > Sorry, I mean dummy regulator. See:
> >
> > https://elixir.bootlin.com/linux/latest/source/drivers/regulator/core.c#L1874
> >
> > On systems that use DT (i.e. have_full_constraints() == true), when the
> > regulator is not found (ENODEV, not specified in DT), regulator_get will return
> > a fake dummy regulator that can be enabled/disabled, but doesn't do anything
> > real.
>
> Hi Ondrej
>
> But we also gain a new warning:
>
> dev_warn(dev,
> "%s supply %s not found, using dummy regulator\n",
> devname, id);
>
> This regulator is clearly optional, so there should not be a warning.
>
> Maybe you can add a new get_type, OPTIONAL_GET, which does not issue
> the warning, but does give back a dummy regulator.

We already had a info message. See my other e-mail with the dmesg output.

IMO, that warning is useful during development, and more informative than the
previous one.

regards,
o.

> Thanks
> Andrew
>
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