lkml.org 
[lkml]   [2021]   [Dec]   [16]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] arm64: dts: sc7180: Add board regulators for MIPI camera trogdor boards
On Wed, Dec 15, 2021 at 08:43:21PM -0800, Stephen Boyd wrote:
> Quoting Matthias Kaehlcke (2021-12-15 18:31:41)
> > On Tue, Dec 14, 2021 at 04:36:38PM -0800, Stephen Boyd wrote:
> > > diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> > > index d4f4441179fc..1dd8e35093a8 100644
> > > --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> > > +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi
> > > @@ -113,6 +113,40 @@ src_vph_pwr: src-vph-pwr-regulator {
> > > vin-supply = <&ppvar_sys>;
> > > };
> > >
> > > + pp1800_uf_cam: pp1800-uf-cam-regulator {
> > > + compatible = "regulator-fixed";
> > > + regulator-name = "pp1800_uf_cam";
> > > + status = "disabled";
> > > +
> > > + regulator-min-microvolt = <1800000>;
> > > + regulator-max-microvolt = <1800000>;
> > > +
> > > + gpio = <&tlmm 6 GPIO_ACTIVE_HIGH>;
> > > + enable-active-high;
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&uf_cam_en>;
> > > +
> > > + vin-supply = <&pp1800_ldo>;
> > > + regulator-enable-ramp-delay = <1000>;
> > > + };
> > > +
> > > + pp1800_wf_cam: pp1800-wf-cam-regulator {
> > > + compatible = "regulator-fixed";
> > > + regulator-name = "pp1800_wf_cam";
> > > + status = "disabled";
> > > +
> > > + regulator-min-microvolt = <1800000>;
> > > + regulator-max-microvolt = <1800000>;
> > > +
> > > + gpio = <&tlmm 7 GPIO_ACTIVE_HIGH>;
> > > + enable-active-high;
> > > + pinctrl-names = "default";
> > > + pinctrl-0 = <&wf_cam_en>;
> > > +
> > > + vin-supply = <&pp1800_ldo>;
> > > + regulator-enable-ramp-delay = <1000>;
> > > + };
> > > +
> >
> > Shouldn't 'pp1800_ldo' be defined before these ("FIXED REGULATORS
> > - parents above children")?
>
> Good catch! Fixed it.
>
> >
> > I suggest to move these two below the top level regulators, i.e.
> > somwhere after pp3300_a (probably pp3300_a and pp5000_a should be
> > swapped, but that's beyond the scope of this patch).
> >
> > > pp5000_a: pp5000-a-regulator {
> > > compatible = "regulator-fixed";
> > > regulator-name = "pp5000_a";
> > > @@ -1517,4 +1611,32 @@ pinconf-sd-cd {
> > > drive-strength = <2>;
> > > };
> > > };
> > > +
> > > + uf_cam_en: uf-cam-en {
> > > + pinmux {
> > > + pins = "gpio6";
> > > + function = "gpio";
> > > + };
> > > +
> > > + pinconf {
> > > + pins = "gpio6";
> > > + drive-strength = <2>;
> > > + /* External pull down */
> >
> > Is there actually an external pull down?
>
> My understanding is that there's an internal pull down in the LDO so
> while it isn't exactly "external" in the sense there's a pull down on
> the net via a resistor, there's still a pull down that you can't see in
> the schematic in the IC.

Thanks for the clarification!

\
 
 \ /
  Last update: 2021-12-16 16:15    [W:0.112 / U:2.268 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site