On Fri, Mar 26, 2021 at 04:54:56PM +0800, Longfang Liu wrote: > When OHCI enters the S4 sleep state, the USB sleep process will call > check_root_hub_suspend() and ohci_bus_suspend() instead of > ohci_suspend() and ohci_bus_suspend(), this causes the OHCI interrupt > to not be closed. What on earth are you talking about? This isn't true at all. Can you provide more information about your system? Are you using a PCI-based OHCI controller or a platform device (and if so, which one)? Can you post system logs to back up your statements? The proper order of calls is ohci_bus_suspend, then check_root_hub_suspended, then ohci_suspend. Often the first one is called some time before the other two. > At this time, if just one device interrupt is reported. Since rh_state > has been changed to OHCI_RH_SUSPENDED after ohci_bus_suspend(), the > driver will not process and close this device interrupt. It will cause > the entire system to be stuck during sleep, causing the device to > fail to respond. > > When the abnormal interruption reaches 100,000 times, the system will > forcibly close the interruption and make the device unusable. > > Since the problem is that the interrupt is not closed, we copied the > interrupt shutdown operation of ohci_suspend() into ohci_bus_suspend() > during the S4 sleep period. We found that this method can solve this > problem. > > At present, we hope to be able to call ohci_suspend() directly during > the sleep process of S4. Do you have any suggestions for this > modification? > > Signed-off-by: Longfang Liu <liulongfang@xxxxxxxxxx> > --- > drivers/usb/host/ohci-hub.c | 13 ++++++++++++- > 1 file changed, 12 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c > index 634f3c7..d468cef 100644 > --- a/drivers/usb/host/ohci-hub.c > +++ b/drivers/usb/host/ohci-hub.c > @@ -315,6 +315,14 @@ static int ohci_bus_suspend (struct usb_hcd *hcd) > del_timer_sync(&ohci->io_watchdog); > ohci->prev_frame_no = IO_WATCHDOG_OFF; > } > + > + spin_lock_irqsave(&ohci->lock, flags); > + ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable); > + (void)ohci_readl(ohci, &ohci->regs->intrdisable); > + > + clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); > + spin_unlock_irqrestore(&ohci->lock, flags); This is completely wrong. The hardware certainly remains accessible when the root hub stops running. The HW_ACCESSIBLE flag should not be cleared here. And if the Master Interrupt Enable bit is cleared, how will the driver ever learn if a remote wakeup request (such as a plug or unplug event) occurs? Alan Stern > + > return rc; > } > > @@ -326,7 +334,10 @@ static int ohci_bus_resume (struct usb_hcd *hcd) > if (time_before (jiffies, ohci->next_statechange)) > msleep(5); > > - spin_lock_irq (&ohci->lock); > + spin_lock_irq(&ohci->lock); > + set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags); > + ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrenable); > + ohci_readl(ohci, &ohci->regs->intrenable); > > if (unlikely(!HCD_HW_ACCESSIBLE(hcd))) > rc = -ESHUTDOWN; > -- > 2.8.1 >
