USB: Fix runtime wakeup on OHCI

At least some OHCI hardware (such as the MCP89) fails to flag any change
in the host status register or the port status registers when receiving
a remote wakeup while in D3 state. This results in the controller being
resumed but no device state change being noticed, at which point the
controller is put back to sleep again. Since there doesn't seem to be any
reliable way to identify the state change, just unconditionally resume the
hub. It'll be put back to sleep in the near future anyway if there are no
active devices attached to it.

Signed-off-by: Matthew Garrett <mjg@redhat.com>
Cc: stable <stable@vger.kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/usb/host/ohci-hub.c b/drivers/usb/host/ohci-hub.c
index 9154615..2f00040 100644 (file)
--- a/drivers/usb/host/ohci-hub.c
+++ b/drivers/usb/host/ohci-hub.c
@@ -356,10 +356,7 @@ static void ohci_finish_controller_resume(struct usb_hcd *hcd)
                msleep(20);
        }
 
-       /* Does the root hub have a port wakeup pending? */
-       if (ohci_readl(ohci, &ohci->regs->intrstatus) &
-                       (OHCI_INTR_RD | OHCI_INTR_RHSC))
-               usb_hcd_resume_root_hub(hcd);
+       usb_hcd_resume_root_hub(hcd);
 }
 
 /* Carry out polling-, autostop-, and autoresume-related state changes */