2 files changed, 7 insertions, 3 deletions

diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
index e15773598e4e..2e8e5bf6b6ca 100644
--- a/drivers/usb/host/xhci-hcd.c
+++ b/drivers/usb/host/xhci-hcd.c
@@ -249,9 +249,9 @@ static void xhci_work(struct xhci_hcd *xhci)
         /* FIXME this should be a delayed service routine that clears the EHB */
         xhci_handle_event(xhci);
 
-        /* Clear the event handler busy flag; the event ring should be empty. */
+        /* Clear the event handler busy flag (RW1C); the event ring should be empty. */
         temp_64 = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
-        xhci_write_64(xhci, temp_64 & ~ERST_EHB, &xhci->ir_set->erst_dequeue);
+        xhci_write_64(xhci, temp_64 | ERST_EHB, &xhci->ir_set->erst_dequeue);
         /* Flush posted writes -- FIXME is this necessary? */
         xhci_readl(xhci, &xhci->ir_set->irq_pending);
 }
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 5dd3b1fd71c0..fe9541a89a3d 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -248,8 +248,12 @@ void xhci_set_hc_event_deq(struct xhci_hcd *xhci)
         /* Update HC event ring dequeue pointer */
         temp = xhci_read_64(xhci, &xhci->ir_set->erst_dequeue);
         temp &= ERST_PTR_MASK;
+        /* Don't clear the EHB bit (which is RW1C) because
+         * there might be more events to service.
+         */
+        temp &= ~ERST_EHB;
         if (!in_interrupt())
-                xhci_dbg(xhci, "// Write event ring dequeue pointer\n");
+                xhci_dbg(xhci, "// Write event ring dequeue pointer, preserving EHB bit\n");
         xhci_write_64(xhci, ((u64) deq & (u64) ~ERST_PTR_MASK) | temp,
                         &xhci->ir_set->erst_dequeue);
 }