On Wed, 25 Mar 2020, Qais Yousef wrote: > Thanks for all the hints Alan. > > I think I figured it out, the below patch seems to fix it for me. Looking > at other drivers resume functions it seems we're missing the > pm_runtime_disable()->set_active()->enable() dance. Doing that fixes the > warning and the dev_err() in driver/base/power. Ah, yes. This should have been added years ago; guess I forgot. :-( > I don't see xhci-plat.c doing that, I wonder if it needs it too. > > I'm not well versed about the details and the rules here. So my fix could be > a hack, though it does seem the right thing to do. > > I wonder why the power core doesn't handle this transparently.. Initially, we didn't want the PM core to do this automatically because we thought some devices might want to remain runtime-suspended following a system resume, and only the device driver would know what to do. Raphael, now that we have the direct_complete mechanism, can we revisit this? Should the PM core automatically call pm_runtime_set_active() if dev->power.direct_complete isn't set? Perhaps in device_resume_early() prior to the pm_runtime_enable() call? It's possible we discussed this and decided against it at the time when direct_complete was added, but if so I don't remember what was said. Alan Stern > diff --git a/drivers/usb/host/ohci-platform.c b/drivers/usb/host/ohci-platform.c > index 7addfc2cbadc..eb92c8092fae 100644 > --- a/drivers/usb/host/ohci-platform.c > +++ b/drivers/usb/host/ohci-platform.c > @@ -299,6 +299,10 @@ static int ohci_platform_resume(struct device *dev) > } > > ohci_resume(hcd, false); > + > + pm_runtime_disable(dev); > + pm_runtime_set_active(dev); > + pm_runtime_enable(dev); > return 0; > } > #endif /* CONFIG_PM_SLEEP */ > > > Thanks > > -- > Qais Yousef
