On Mon, 4 Mar 2013, Vivek Gautam wrote: > >> @@ -149,6 +150,8 @@ static int xhci_plat_probe(struct platform_device *pdev) > >> if (ret) > >> goto put_usb3_hcd; > >> > >> + pm_runtime_enable(&pdev->dev); > > > > This is generally not a good idea. You shouldn't enable a device for > > runtime PM without first telling the PM core what state it is in. > > > Right, but i am not completely sure on any fixed path to follow for > enabling runtime > power management on a device. :-( > Does it become necessary to "pm_runtime_set_active" or > "pm_runtime_set_suspended" a device > before "pm_runtime_enable" ? Yes, it usually is necesary. And especially here, because the runtime PM core sets the initial status of every device to RPM_SUSPENDED. > pm_runtime_enable would just try to > decrement the disable_depth > of the device. That's right. And once that happens, the PM core would think the device was suspended even though it was really at full power. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
