3 files changed, 18 insertions, 1 deletions

diff --git a/drivers/usb/core/hcd-pci.c b/drivers/usb/core/hcd-pci.c
index e387e394f876..352577baa53d 100644
--- a/drivers/usb/core/hcd-pci.c
+++ b/drivers/usb/core/hcd-pci.c
@@ -388,8 +388,20 @@ static int hcd_pci_suspend(struct device *dev)
         if (hcd->driver->pci_suspend) {
                 bool    do_wakeup = device_may_wakeup(dev);
 
+                /* Optimization: Don't suspend if a root-hub wakeup is
+                 * pending and it would cause the HCD to wake up anyway.
+                 */
+                if (do_wakeup && HCD_WAKEUP_PENDING(hcd))
+                        return -EBUSY;
                 retval = hcd->driver->pci_suspend(hcd, do_wakeup);
                 suspend_report_result(hcd->driver->pci_suspend, retval);
+
+                /* Check again in case wakeup raced with pci_suspend */
+                if (retval == 0 && do_wakeup && HCD_WAKEUP_PENDING(hcd)) {
+                        if (hcd->driver->pci_resume)
+                                hcd->driver->pci_resume(hcd, false);
+                        retval = -EBUSY;
+                }
                 if (retval)
                         return retval;
         }
diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c
index f2fe7c8e991d..0358c05e6e8a 100644
--- a/drivers/usb/core/hcd.c
+++ b/drivers/usb/core/hcd.c
@@ -1940,6 +1940,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg)
 
         dev_dbg(&rhdev->dev, "usb %s%s\n",
                         (msg.event & PM_EVENT_AUTO ? "auto-" : ""), "resume");
+        clear_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
         if (!hcd->driver->bus_resume)
                 return -ENOENT;
         if (hcd->state == HC_STATE_RUNNING)
@@ -1993,8 +1994,10 @@ void usb_hcd_resume_root_hub (struct usb_hcd *hcd)
         unsigned long flags;
 
         spin_lock_irqsave (&hcd_root_hub_lock, flags);
-        if (hcd->rh_registered)
+        if (hcd->rh_registered) {
+                set_bit(HCD_FLAG_WAKEUP_PENDING, &hcd->flags);
                 queue_work(pm_wq, &hcd->wakeup_work);
+        }
         spin_unlock_irqrestore (&hcd_root_hub_lock, flags);
 }
 EXPORT_SYMBOL_GPL(usb_hcd_resume_root_hub);
diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
index ae10020b4023..3b571f1ffbb3 100644
--- a/include/linux/usb/hcd.h
+++ b/include/linux/usb/hcd.h
@@ -98,6 +98,7 @@ struct usb_hcd {
 #define HCD_FLAG_SAW_IRQ                1
 #define HCD_FLAG_POLL_RH                2       /* poll for rh status? */
 #define HCD_FLAG_POLL_PENDING           3       /* status has changed? */
+#define HCD_FLAG_WAKEUP_PENDING         4       /* root hub is resuming? */
 
         /* The flags can be tested using these macros; they are likely to
          * be slightly faster than test_bit().
@@ -106,6 +107,7 @@ struct usb_hcd {
 #define HCD_SAW_IRQ(hcd)        ((hcd)->flags & (1U << HCD_FLAG_SAW_IRQ))
 #define HCD_POLL_RH(hcd)        ((hcd)->flags & (1U << HCD_FLAG_POLL_RH))
 #define HCD_POLL_PENDING(hcd)   ((hcd)->flags & (1U << HCD_FLAG_POLL_PENDING))
+#define HCD_WAKEUP_PENDING(hcd) ((hcd)->flags & (1U << HCD_FLAG_WAKEUP_PENDING))
 
         /* Flags that get set only during HCD registration or removal. */
         unsigned                rh_registered:1;/* is root hub registered? */