Re: [PATCH 2/2] ARM: DTS: Add devicetree file for the Galaxy S2

From: PaweÅ Chmiel
Date: Tue Mar 31 2020 - 11:30:06 EST


On Tue, 2020-03-31 at 15:55 +0200, Marek Szyprowski wrote:
> Hi Paul,
>
> On 2020-03-31 15:09, Paul Cercueil wrote:
> > Cc: PaweÅ Chmiel <pawel.mikolaj.chmiel@xxxxxxxxx>
> >
> > Hi Marek,
> >
> > Le mar. 31 mars 2020 Ã 7:36, Marek Szyprowski
> > <m.szyprowski@xxxxxxxxxxx> a Ãcrit :
> > > Hi Paul,
> > >
> > > On 2020-03-18 15:25, Paul Cercueil wrote:
> > > > > > + };
> > > > > > +
> > > > > > + tsp_reg: regulator-1 {
> > > > > > + compatible = "regulator-fixed";
> > > > > > + regulator-name = "TSP_FIXED_VOLTAGES";
> > > > > > + regulator-min-microvolt = <3300000>;
> > > > > > + regulator-max-microvolt = <3300000>;
> > > > > > + gpio = <&gpl0 3 GPIO_ACTIVE_HIGH>;
> > > > > > + startup-delay-us = <70000>;
> > > > > > + enable-active-high;
> > > > > > + regulator-boot-on;
> > > > > > + regulator-always-on;
> > > > >
> > > > > always-on and boot-on should not be needed. You have a consumer
> > > > > for this
> > > > > regulator.
> > > >
> > > > About this: the touchscreen driver does not use a regulator, so I
> > > > believe that's why these properties were here.
> > > >
> > > > I sent patches upstream to address the issue:
> > > > https://protect2.fireeye.com/url?k=e8aedc29-b53072b3-e8af5766-0cc47a336fae-759579fd576d8382&u=https://lkml.org/lkml/2020/3/15/94
> > > >
> > > >
> > > > I believe this means I cannot merge the i9100 devicetree until it is
> > > > acked.
> > >
> > > One more information - similar change has been already posted, but it
> > > looks it got lost then: https://patchwork.kernel.org/patch/10550903/
> >
> > I was aware of this patch, but didn't know it was sent upstream.
> >
> > This other patch uses two regulators, vdd/avdd but doesn't give any
> > reason why.
> >
> I've checked the UniversalC210 schematic, which uses the same
> touchscreen chip. There are 2 supplies to the touchscreen chip: 2.8V VDD
> and 3.3V AVDD. Both are enabled by the same GPIO pin though. There is
> however no reset GPIO pin there.
Hi
Don't remember now how it worked on Galaxy S1, but it looks like it has
the same setup - two regulators enabled by one GPIO pin.
>
> > PaweÅ, is that really needed?
> >
> Best regards