If the connected USB2 device wakeup is not enabled/supported, the link state may still be U0 when do xhci bus suspend, after we suspend ports in U0, we need give time to device to enter suspend before do further suspend operations (e.g. system suspend), otherwise we may enter system suspend with link state at U0. Signed-off-by: Li Jun <jun.li@xxxxxxx> --- Change for v2: -Use bus_state->bus_suspended to check if any port may be at U0. drivers/usb/host/xhci-hub.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index c799ca5..74c497f 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -1712,6 +1712,10 @@ int xhci_bus_suspend(struct usb_hcd *hcd) hcd->state = HC_STATE_SUSPENDED; bus_state->next_statechange = jiffies + msecs_to_jiffies(10); spin_unlock_irqrestore(&xhci->lock, flags); + + if (bus_state->bus_suspended) + usleep_range(5000, 10000); + return 0; } -- 2.7.4
