4 files changed, 57 insertions, 2 deletions

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index a686cf4905bb..68914429482f 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -761,12 +761,39 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 			break;
 		case USB_PORT_FEAT_LINK_STATE:
 			temp = xhci_readl(xhci, port_array[wIndex]);
+
+			/* Disable port */
+			if (link_state == USB_SS_PORT_LS_SS_DISABLED) {
+				xhci_dbg(xhci, "Disable port %d\n", wIndex);
+				temp = xhci_port_state_to_neutral(temp);
+				/*
+				 * Clear all change bits, so that we get a new
+				 * connection event.
+				 */
+				temp |= PORT_CSC | PORT_PEC | PORT_WRC |
+					PORT_OCC | PORT_RC | PORT_PLC |
+					PORT_CEC;
+				xhci_writel(xhci, temp | PORT_PE,
+					port_array[wIndex]);
+				temp = xhci_readl(xhci, port_array[wIndex]);
+				break;
+			}
+
+			/* Put link in RxDetect (enable port) */
+			if (link_state == USB_SS_PORT_LS_RX_DETECT) {
+				xhci_dbg(xhci, "Enable port %d\n", wIndex);
+				xhci_set_link_state(xhci, port_array, wIndex,
+						link_state);
+				temp = xhci_readl(xhci, port_array[wIndex]);
+				break;
+			}
+
 			/* Software should not attempt to set
-			 * port link state above '5' (Rx.Detect) and the port
+			 * port link state above '3' (U3) and the port
 			 * must be enabled.
 			 */
 			if ((temp & PORT_PE) == 0 ||
-				(link_state > USB_SS_PORT_LS_RX_DETECT)) {
+				(link_state > USB_SS_PORT_LS_U3)) {
 				xhci_warn(xhci, "Cannot set link state.\n");
 				goto error;
 			}
@@ -957,6 +984,7 @@ int xhci_hub_status_data(struct usb_hcd *hcd, char *buf)
 	int max_ports;
 	__le32 __iomem **port_array;
 	struct xhci_bus_state *bus_state;
+	bool reset_change = false;
 
 	max_ports = xhci_get_ports(hcd, &port_array);
 	bus_state = &xhci->bus_state[hcd_index(hcd)];
@@ -988,6 +1016,12 @@ int xhci_hub_status_data(struct usb_hcd *hcd, char *buf)
 			buf[(i + 1) / 8] |= 1 << (i + 1) % 8;
 			status = 1;
 		}
+		if ((temp & PORT_RC))
+			reset_change = true;
+	}
+	if (!status && !reset_change) {
+		xhci_dbg(xhci, "%s: stopping port polling.\n", __func__);
+		clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 	}
 	spin_unlock_irqrestore(&xhci->lock, flags);
 	return status ? retval : 0;
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index fb51c7085ad0..35616ffbe3ae 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1250,6 +1250,8 @@ static unsigned int xhci_microframes_to_exponent(struct usb_device *udev,
 static unsigned int xhci_parse_microframe_interval(struct usb_device *udev,
 		struct usb_host_endpoint *ep)
 {
+	if (ep->desc.bInterval == 0)
+		return 0;
 	return xhci_microframes_to_exponent(udev, ep,
 			ep->desc.bInterval, 0, 15);
 }
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index cbb44b7b9d65..59fb5c677dbe 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -1725,6 +1725,15 @@ cleanup:
 	if (bogus_port_status)
 		return;
 
+	/*
+	 * xHCI port-status-change events occur when the "or" of all the
+	 * status-change bits in the portsc register changes from 0 to 1.
+	 * New status changes won't cause an event if any other change
+	 * bits are still set.  When an event occurs, switch over to
+	 * polling to avoid losing status changes.
+	 */
+	xhci_dbg(xhci, "%s: starting port polling.\n", __func__);
+	set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
 	spin_unlock(&xhci->lock);
 	/* Pass this up to the core */
 	usb_hcd_poll_rh_status(hcd);
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 5c72c431bab1..f1f01a834ba7 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -884,6 +884,11 @@ int xhci_suspend(struct xhci_hcd *xhci)
 			xhci->shared_hcd->state != HC_STATE_SUSPENDED)
 		return -EINVAL;
 
+	/* Don't poll the roothubs on bus suspend. */
+	xhci_dbg(xhci, "%s: stopping port polling.\n", __func__);
+	clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+	del_timer_sync(&hcd->rh_timer);
+
 	spin_lock_irq(&xhci->lock);
 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
 	clear_bit(HCD_FLAG_HW_ACCESSIBLE, &xhci->shared_hcd->flags);
@@ -1069,6 +1074,11 @@ int xhci_resume(struct xhci_hcd *xhci, bool hibernated)
 	if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
 		compliance_mode_recovery_timer_init(xhci);
 
+	/* Re-enable port polling. */
+	xhci_dbg(xhci, "%s: starting port polling.\n", __func__);
+	set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
+	usb_hcd_poll_rh_status(hcd);
+
 	return retval;
 }
 #endif	/* CONFIG_PM */