Re: [PATCH stable-5.15 3/3] usb: dwc3: disable USB core PHY management

[Johan Hovold <johan@kernel.org>]

On Thu, Oct 27, 2022 at 02:45:15PM +0200, Johan Hovold wrote:
> On Wed, Oct 26, 2022 at 03:11:00PM +0200, Stefan Agner wrote:

> > The user reports the S-ATA disk is *not* recognized with that patch
> > applied.
> 
> I just noticed a mistake in the instrumentation patch I sent you. Could
> you try moving the calibrations calls after dwc3_host_init() (e.g. as in
> the second chunk in the diff below)?
> 
> As mentioned in the commit message for a0a465569b45 ("usb: dwc3: remove
> generic PHY calibrate() calls"), this may not work if the xhci-plat
> driver is built as a module and there are some corner cases that it does
> not cover.
> 
> It seems we should revert the offending commit and then try to find some
> time to untangle this mess, but please check if the below addresses the
> issue first so we know what the problem is.
> 
> I'll prepare a revert in the meantime.

I've now posted the revert, but please do check if the below patch was
enough to resolve the immediate issue.

Johan

> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 31156d4dec9f..37d49a394912 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -197,6 +197,8 @@ static void __dwc3_set_mode(struct work_struct *work)
>                                 otg_set_vbus(dwc->usb2_phy->otg, true);
>                         phy_set_mode(dwc->usb2_generic_phy, PHY_MODE_USB_HOST);
>                         phy_set_mode(dwc->usb3_generic_phy, PHY_MODE_USB_HOST);
> +                       phy_calibrate(dwc->usb2_generic_phy);
> +                       phy_calibrate(dwc->usb3_generic_phy);
>                         if (dwc->dis_split_quirk) {
>                                 reg = dwc3_readl(dwc->regs, DWC3_GUCTL3);
>                                 reg |= DWC3_GUCTL3_SPLITDISABLE;
> @@ -1391,6 +1393,9 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
>                 ret = dwc3_host_init(dwc);
>                 if (ret)
>                         return dev_err_probe(dev, ret, "failed to initialize host\n");
> +
> +               phy_calibrate(dwc->usb2_generic_phy);
> +               phy_calibrate(dwc->usb3_generic_phy);
>                 break;
>         case USB_DR_MODE_OTG:
>                 INIT_WORK(&dwc->drd_work, __dwc3_set_mode);