Re: [PATCH 2/3] ARM: DTS: imx6q-logicpd: Reduce inrush current on start

[Adam Ford]

On Wed, Mar 20, 2019 at 7:45 AM Shawn Guo <shawnguo@xxxxxxxxxx> wrote:
>
> On Wed, Mar 06, 2019 at 08:04:00AM -0600, Adam Ford wrote:
> > The main 3.3V regulator sources a series of additional regulators.
> > This patch adds a small delay, so when the 3.3V regulator comes
> > on it delays a bit before the subsequent regulators can come on.
> > This reduces the inrush current a bit on the external DC power
> > supply.
> >
> > Fixes: 1c207f911fe9 ("ARM: dts: imx: Add support for Logic PD
> > i.MX6QD EVM")
>
> Same comment as patch #1.

The sourcing regulator occasionally cuts out because the inrush is so
high.  I would argue that preventing a hardware issue like that would
be a 'fix' and if it helps, I could add that to the description.

>
> >
> > Signed-off-by: Adam Ford <aford173@xxxxxxxxx>
>
> To match the convention, the 'DTS' in subject prefix should be
> lowercase.

I will fix in V2.

>
> Shawn

adam
>
> >
> > diff --git a/arch/arm/boot/dts/imx6-logicpd-baseboard.dtsi b/arch/arm/boot/dts/imx6-logicpd-baseboard.dtsi
> > index fb01fa6e4224..e31b6923cb72 100644
> > --- a/arch/arm/boot/dts/imx6-logicpd-baseboard.dtsi
> > +++ b/arch/arm/boot/dts/imx6-logicpd-baseboard.dtsi
> > @@ -99,6 +99,7 @@
> >               regulator-min-microvolt = <3300000>;
> >               regulator-max-microvolt = <3300000>;
> >               gpio = <&gpio1 26 GPIO_ACTIVE_HIGH>;
> > +             startup-delay-us = <70000>;
> >               enable-active-high;
> >               regulator-always-on;
> >       };
> > --
> > 2.17.1
> >