3 files changed, 14 insertions, 10 deletions

diff --git a/drivers/usb/host/ehci-hcd.c b/drivers/usb/host/ehci-hcd.c
index 369a8a5ea7b..d9d53f289ca 100644
--- a/drivers/usb/host/ehci-hcd.c
+++ b/drivers/usb/host/ehci-hcd.c
@@ -84,7 +84,7 @@ static const char	hcd_name [] = "ehci_hcd";
 #define EHCI_IAA_MSECS		10		/* arbitrary */
 #define EHCI_IO_JIFFIES		(HZ/10)		/* io watchdog > irq_thresh */
 #define EHCI_ASYNC_JIFFIES	(HZ/20)		/* async idle timeout */
-#define EHCI_SHRINK_JIFFIES	(HZ/200)	/* async qh unlink delay */
+#define EHCI_SHRINK_FRAMES	5		/* async qh unlink delay */
 
 /* Initial IRQ latency:  faster than hw default */
 static int log2_irq_thresh = 0;		// 0 to 6
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c
index b85b54160cd..2622b6596d7 100644
--- a/drivers/usb/host/ehci-q.c
+++ b/drivers/usb/host/ehci-q.c
@@ -1116,8 +1116,7 @@ static void scan_async (struct ehci_hcd *ehci)
 	struct ehci_qh		*qh;
 	enum ehci_timer_action	action = TIMER_IO_WATCHDOG;
 
-	if (!++(ehci->stamp))
-		ehci->stamp++;
+	ehci->stamp = ehci_readl(ehci, &ehci->regs->frame_index);
 	timer_action_done (ehci, TIMER_ASYNC_SHRINK);
 rescan:
 	qh = ehci->async->qh_next.qh;
@@ -1142,18 +1141,20 @@ rescan:
 				}
 			}
 
-			/* unlink idle entries, reducing HC PCI usage as well
+			/* unlink idle entries, reducing DMA usage as well
 			 * as HCD schedule-scanning costs.  delay for any qh
 			 * we just scanned, there's a not-unusual case that it
 			 * doesn't stay idle for long.
 			 * (plus, avoids some kind of re-activation race.)
 			 */
-			if (list_empty (&qh->qtd_list)) {
-				if (qh->stamp == ehci->stamp)
+			if (list_empty(&qh->qtd_list)
+					&& qh->qh_state == QH_STATE_LINKED) {
+				if (!ehci->reclaim
+					&& ((ehci->stamp - qh->stamp) & 0x1fff)
+						>= (EHCI_SHRINK_FRAMES * 8))
+					start_unlink_async(ehci, qh);
+				else
 					action = TIMER_ASYNC_SHRINK;
-				else if (!ehci->reclaim
-					    && qh->qh_state == QH_STATE_LINKED)
-					start_unlink_async (ehci, qh);
 			}
 
 			qh = qh->qh_next.qh;
diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 90245fd8bac..5799298364f 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -198,7 +198,10 @@ timer_action (struct ehci_hcd *ehci, enum ehci_timer_action action)
 			break;
 		// case TIMER_ASYNC_SHRINK:
 		default:
-			t = EHCI_SHRINK_JIFFIES;
+			/* add a jiffie since we synch against the
+			 * 8 KHz uframe counter.
+			 */
+			t = DIV_ROUND_UP(EHCI_SHRINK_FRAMES * HZ, 1000) + 1;
 			break;
 		}
 		mod_timer(&ehci->watchdog, t + jiffies);