On Sat, 27 Apr 2013, ZhenHua wrote: > On 04/27/2013 12:51 AM, Alan Stern wrote: > > On Fri, 26 Apr 2013, ZhenHua wrote: > > > >> There is a function wait_for_HP() in uhci-hub.c. In this > >> patch, it is used in suspend_rh(), I think this can be a > >> solution. And I have tested this patch, it can fix the bug. > >> > >> I think there is another patch needed. As Alan said in another > >> mail, in the UHCI_RH_RUNNING_NODEVS case, it should not be stopped > >> if the uhci device is HP iLo virtual usb. > > I believe that if you change the UHCI_RH_RUNNING_NODEVS case, you will > > find that this patch (calling wait_for_HP) isn't needed. > > > > In fact, the patch is so easy that I am including it below. Please > > test this (without either of your patches) to see if it works. > > > > Alan Stern > > > > > > > > > > Index: usb-3.9/drivers/usb/host/uhci-hub.c > > =================================================================== > > --- usb-3.9.orig/drivers/usb/host/uhci-hub.c > > +++ usb-3.9/drivers/usb/host/uhci-hub.c > > @@ -225,7 +225,8 @@ static int uhci_hub_status_data(struct u > > /* auto-stop if nothing connected for 1 second */ > > if (any_ports_active(uhci)) > > uhci->rh_state = UHCI_RH_RUNNING; > > - else if (time_after_eq(jiffies, uhci->auto_stop_time)) > > + else if (time_after_eq(jiffies, uhci->auto_stop_time) && > > + !uhci->wait_for_hp) > > suspend_rh(uhci, UHCI_RH_AUTO_STOPPED); > > break; > > > > > I have tested the UHCI_RH_RUNNING_NODEVS case yeasterday, and it works. > But the function suspend_rh is also called in other places, so I think > it only fixes > the warning when auto stop is called, but not fix the warning when > uhci's bus_suspend > is called, it will come out again. Have you tried this? I expect the warning will not occur when the bus_suspend routine is called, because then there will be a 1-ms delay, not just a 400-us delay. > And if you add uhci->wait_for_hp check in the UHCI_RH_RUNNING_NODEVS case, > all hp uhci devices will not auto stop, not only the virtual devices. I > guess it may waste resource. If you want, you can add a new flag specifically for virtual controllers. But it shouldn't matter -- as long as your kernels are built with CONFIG_PM_RUNTIME enabled, there won't be any significant waste of resources. 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
