1 files changed, 25 insertions, 2 deletions

diff --git a/drivers/usb/host/ohci-pci.c b/drivers/usb/host/ohci-pci.c
index 5f22e6590cd1..1b09dde068e1 100644
--- a/drivers/usb/host/ohci-pci.c
+++ b/drivers/usb/host/ohci-pci.c
@@ -105,13 +105,36 @@ ohci_pci_start (struct usb_hcd *hcd)
 
 static int ohci_pci_suspend (struct usb_hcd *hcd, pm_message_t message)
 {
-        /* root hub was already suspended */
-        return 0;
+        struct ohci_hcd *ohci = hcd_to_ohci (hcd);
+        unsigned long   flags;
+        int             rc = 0;
+
+        /* Root hub was already suspended. Disable irq emission and
+         * mark HW unaccessible, bail out if RH has been resumed. Use
+         * the spinlock to properly synchronize with possible pending
+         * RH suspend or resume activity.
+         *
+         * This is still racy as hcd->state is manipulated outside of
+         * any locks =P But that will be a different fix.
+         */
+        spin_lock_irqsave (&ohci->lock, flags);
+        if (hcd->state != HC_STATE_SUSPENDED) {
+                rc = -EINVAL;
+                goto bail;
+        }
+        ohci_writel(ohci, OHCI_INTR_MIE, &ohci->regs->intrdisable);
+        (void)ohci_readl(ohci, &ohci->regs->intrdisable);
+        clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+ bail:
+        spin_unlock_irqrestore (&ohci->lock, flags);
+
+        return rc;
 }
 
 
 static int ohci_pci_resume (struct usb_hcd *hcd)
 {
+        set_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
         usb_hcd_resume_root_hub(hcd);
         return 0;
 }