[PATCH 3/4] arm64: dts: qcom: msm8996: Add VDD_MX to QUSB2 PHYs

[Dmitry Baryshkov]

On Wed, Jun 10, 2026 at 12:18:23PM +0000, sashiko-bot at kernel.org wrote:
> Thank you for your contribution! Sashiko AI review found 1 potential issue(s) to consider:
> - [High] Adding the VDD_MX power domain interacts brokenly with the PHY driver's runtime PM implementation, permanently pinning the VDD_MX power rail and causing a severe battery drain regression during system idle.
> --
> 
> commit f3735b6dfcc42f0f55443d0f81c7b256532b0e25
> Author: Konrad Dybcio <konrad.dybcio at oss.qualcomm.com>
> 
> arm64: dts: qcom: msm8996: Add VDD_MX to QUSB2 PHYs
> 
> This commit adds the VDD_MX power rail description to the QUSB2 PHYs in the
> msm8996 device tree. It explicitly sets the power domain and required OPPs
> for both primary and secondary PHY nodes.
> 
> > diff --git a/arch/arm64/boot/dts/qcom/msm8996.dtsi b/arch/arm64/boot/dts/qcom/msm8996.dtsi
> > index 2f67e665996f3..b7cd1928335c8 100644
> > --- a/arch/arm64/boot/dts/qcom/msm8996.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/msm8996.dtsi
> > @@ -3192,7 +3192,12 @@ hsusb_phy1: phy at 7411000 {
> >  			clock-names = "cfg_ahb", "ref";
> >  
> >  			resets = <&gcc GCC_QUSB2PHY_PRIM_BCR>;
> > +
> > +			power-domains = <&rpmpd MSM8996_VDDMX>;
> > +			required-opps = <&rpmpd_opp4>;
> 
> [Severity: High]
> Does adding this power domain permanently pin the VDD_MX rail?
> 
> Looking at the driver in drivers/phy/qualcomm/phy-qcom-qusb2.c,
> qusb2_phy_probe() sets up runtime PM like this:
> 
> 	pm_runtime_set_active(dev);
> 	pm_runtime_forbid(dev);
> 	ret = devm_pm_runtime_enable(dev);
> 
> Because the driver forbids runtime suspend by default, the device stays
> permanently active. 

I think it should be solved separately. For now, let's make sure that
the PHY is properly powered up.


Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov at oss.qualcomm.com>




-- 
With best wishes
Dmitry