Re: [PATCH 0/5] usb: dwc3: qcom: Allow runtime PM

From: Konrad Dybcio
Date: Mon Mar 27 2023 - 05:04:18 EST




On 25.03.2023 17:52, Manivannan Sadhasivam wrote:
> Hi,
>
> This series allows the dwc3-qcom driver to do runtime PM itself without
> userspace intervention. Still, userspace is required to enable runtime PM
> for dwc3 glue and xhci drivers as we cannot enable runtime PM for them.
> But this series avoids one more additional step.
What sort of 'userspace intervention' are we talking about?
echo mem > /sys/power/state?

Konrad
>
> While enabling runtime PM, I noticed that the xhci driver suspends before
> catching the xhci interrupts during resume. This ended up deferring the
> device enumeration for some time. So I included a patch adding autosuspend
> delay of 200ms to the xhci driver. With this delay, usb enumeration happens
> properly.
>
> This series has been tested on SC8280XP-CRD and RB5 devices.
>
> Thanks,
> Mani
>
> Manivannan Sadhasivam (5):
> arm64: dts: qcom: sc8280xp: Add missing dwc3 quirks
> xhci: host: Use 200ms autosuspend delay for runtime suspend
> usb: dwc3: qcom: Fix null ptr access during runtime_suspend()
> usb: dwc3: qcom: Clear pending interrupt before enabling wake
> interrupt
> usb: dwc3: qcom: Allow runtime PM
>
> arch/arm64/boot/dts/qcom/sc8280xp.dtsi | 14 ++++++++++++++
> drivers/usb/dwc3/dwc3-qcom.c | 13 +++++++++----
> drivers/usb/host/xhci-plat.c | 2 ++
> 3 files changed, 25 insertions(+), 4 deletions(-)
>