Re: [PATCH v2 1/2] arm64: dts: qcom: qcs6490-rubikpi3: Add 3.3 V output supply

[Hongyang Zhao <hongyang.zhao@thundersoft.com>]

Thanks for the review!

On 7/22/26 6:12 PM, Hongyang Zhao wrote:
> > Describe the GPIO-controlled VCC3V3_OUTPUT rail. This board-level rail
> > supplies the two camera connectors and the 40-pin expansion header.
> >
> > Signed-off-by: Hongyang Zhao <hongyang.zhao@thundersoft.com>
> > ---
> >  .../boot/dts/qcom/qcs6490-thundercomm-rubikpi3.dts | 24 ++++++++++++++++++++++
> >  1 file changed, 24 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/qcs6490-thundercomm-rubikpi3.dts b/arch/arm64/boot/dts/qcom/qcs6490-thundercomm-rubikpi3.dts
> > index d8a9a7e47bdc..45514918562b 100644
> > --- a/arch/arm64/boot/dts/qcom/qcs6490-thundercomm-rubikpi3.dts
> > +++ b/arch/arm64/boot/dts/qcom/qcs6490-thundercomm-rubikpi3.dts
> > @@ -214,6 +214,23 @@ vreg_usbhub_rest_1v8: regulator-usbhub-rest-1v8 {
> >  		regulator-boot-on;
> >  	};
> >
> > +	vreg_vcc3v3_output: regulator-vcc3v3-output {
> > +		compatible = "regulator-fixed";
> > +
> > +		regulator-name = "vcc3v3_output";
> > +		regulator-min-microvolt = <3300000>;
> > +		regulator-max-microvolt = <3300000>;
> > +
> > +		gpio = <&tlmm 14 GPIO_ACTIVE_HIGH>;
> > +		enable-active-high;
> > +
> > +		pinctrl-0 = <&vcc3v3_output_en>;
> > +		pinctrl-names = "default";
> > +
> > +		regulator-always-on;
> > +		regulator-boot-on;
>
> Is it really on by default at boot?

Before submitting the patch, I measured GPIO14 and found that it was
already high before the kernel started, so I described the regulator
as regulator-boot-on.

I have now checked the bootloader code and confirmed that it does not
drive GPIO14 high. According to the schematic, GPIO14 is actually pulled
high by VREG_L18B_1P8.

Therefore, I will remove regulator-boot-on in the next revision of the
patch series while retaining Bryan's Reviewed-by tag.

Thanks,
Hongyang