Re: [PATCH v10 8/9] arm64: dts: qcom: ipq9574: Add LDO regulator node

From: Dmitry Baryshkov
Date: Sat May 06 2023 - 07:33:30 EST


On Sat, 6 May 2023 at 14:09, Varadarajan Narayanan
<quic_varada@xxxxxxxxxxx> wrote:
>
> On Fri, May 05, 2023 at 12:29:54PM +0300, Dmitry Baryshkov wrote:
> > On Fri, 5 May 2023 at 11:23, Varadarajan Narayanan
> > <quic_varada@xxxxxxxxxxx> wrote:
> > >
> > > Add LDO regulator node
> >
> > As this LDO is provided by the PMIC, it would be nice to know why it
> > is modelled as an always-on regulator instead of the proper PMIC
> > regulator. Up to now we were doing this only for the outstanding power
> > rails like CX/MX or EBI.
>
> These are always ON because USB phy doesn't support power
> collapse, and there is a chance that other IP blocks might be
> sharing the rail.

You are describing the software side here. From the hardware point of
view, it is an I2C regulator, which is probably also exported as an
SMD_RPM regulator. Unless you have a good reason not to do so, there
should be a node under rpm-requests, which describes mp5496 regulators
exported via RPM. then USB should refer to those regulators.

>
> Thanks
> Varada
>
> > > Signed-off-by: Varadarajan Narayanan <quic_varada@xxxxxxxxxxx>
> > > ---
> > > Changes in v10:
> > > - Add LDO regulator node
> > > ---
> > > arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts | 7 +++++++
> > > 1 file changed, 7 insertions(+)
> > >
> > > diff --git a/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts b/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
> > > index bdc1434..1f5d14f 100644
> > > --- a/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
> > > +++ b/arch/arm64/boot/dts/qcom/ipq9574-rdp433.dts
> > > @@ -60,6 +60,13 @@
> > > regulator-min-microvolt = <725000>;
> > > regulator-max-microvolt = <1075000>;
> > > };
> > > +
> > > + mp5496_l2: l2 {
> > > + regulator-min-microvolt = <1800000>;
> > > + regulator-max-microvolt = <1800000>;
> > > + regulator-boot-on;
> > > + regulator-always-on;
> > > + };
> > > };
> > > };
> > >
> > > --
> > > 2.7.4
> > >
> >
> >
> > --
> > With best wishes
> > Dmitry



--
With best wishes
Dmitry