1 files changed, 46 insertions, 14 deletions

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 55b5a5687d79..cb99a7800be7 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -1322,13 +1322,16 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 	__le32 __iomem **port_array;
 	struct xhci_bus_state *bus_state;
 	unsigned long flags;
+	u32 portsc_buf[USB_MAXCHILDREN];
+	bool wake_enabled;
 
 	max_ports = xhci_get_ports(hcd, &port_array);
 	bus_state = &xhci->bus_state[hcd_index(hcd)];
+	wake_enabled = hcd->self.root_hub->do_remote_wakeup;
 
 	spin_lock_irqsave(&xhci->lock, flags);
 
-	if (hcd->self.root_hub->do_remote_wakeup) {
+	if (wake_enabled) {
 		if (bus_state->resuming_ports ||	/* USB2 */
 		    bus_state->port_remote_wakeup) {	/* USB3 */
 			spin_unlock_irqrestore(&xhci->lock, flags);
@@ -1336,26 +1339,36 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 			return -EBUSY;
 		}
 	}
-
-	port_index = max_ports;
+	/*
+	 * Prepare ports for suspend, but don't write anything before all ports
+	 * are checked and we know bus suspend can proceed
+	 */
 	bus_state->bus_suspended = 0;
+	port_index = max_ports;
 	while (port_index--) {
-		/* suspend the port if the port is not suspended */
 		u32 t1, t2;
-		int slot_id;
 
 		t1 = readl(port_array[port_index]);
 		t2 = xhci_port_state_to_neutral(t1);
+		portsc_buf[port_index] = 0;
 
-		if ((t1 & PORT_PE) && !(t1 & PORT_PLS_MASK)) {
-			xhci_dbg(xhci, "port %d not suspended\n", port_index);
-			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-					port_index + 1);
-			if (slot_id) {
+		/* Bail out if a USB3 port has a new device in link training */
+		if ((t1 & PORT_PLS_MASK) == XDEV_POLLING) {
+			bus_state->bus_suspended = 0;
+			spin_unlock_irqrestore(&xhci->lock, flags);
+			xhci_dbg(xhci, "Bus suspend bailout, port in polling\n");
+			return -EBUSY;
+		}
+
+		/* suspend ports in U0, or bail out for new connect changes */
+		if ((t1 & PORT_PE) && (t1 & PORT_PLS_MASK) == XDEV_U0) {
+			if ((t1 & PORT_CSC) && wake_enabled) {
+				bus_state->bus_suspended = 0;
 				spin_unlock_irqrestore(&xhci->lock, flags);
-				xhci_stop_device(xhci, slot_id, 1);
-				spin_lock_irqsave(&xhci->lock, flags);
+				xhci_dbg(xhci, "Bus suspend bailout, port connect change\n");
+				return -EBUSY;
 			}
+			xhci_dbg(xhci, "port %d not suspended\n", port_index);
 			t2 &= ~PORT_PLS_MASK;
 			t2 |= PORT_LINK_STROBE | XDEV_U3;
 			set_bit(port_index, &bus_state->bus_suspended);
@@ -1364,7 +1377,7 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 		 * including the USB 3.0 roothub, but only if CONFIG_PM
 		 * is enabled, so also enable remote wake here.
 		 */
-		if (hcd->self.root_hub->do_remote_wakeup) {
+		if (wake_enabled) {
 			if (t1 & PORT_CONNECT) {
 				t2 |= PORT_WKOC_E | PORT_WKDISC_E;
 				t2 &= ~PORT_WKCONN_E;
@@ -1377,7 +1390,26 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 
 		t1 = xhci_port_state_to_neutral(t1);
 		if (t1 != t2)
-			writel(t2, port_array[port_index]);
+			portsc_buf[port_index] = t2;
+	}
+
+	/* write port settings, stopping and suspending ports if needed */
+	port_index = max_ports;
+	while (port_index--) {
+		if (!portsc_buf[port_index])
+			continue;
+		if (test_bit(port_index, &bus_state->bus_suspended)) {
+			int slot_id;
+
+			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
+							    port_index + 1);
+			if (slot_id) {
+				spin_unlock_irqrestore(&xhci->lock, flags);
+				xhci_stop_device(xhci, slot_id, 1);
+				spin_lock_irqsave(&xhci->lock, flags);
+			}
+		}
+		writel(portsc_buf[port_index], port_array[port_index]);
 	}
 	hcd->state = HC_STATE_SUSPENDED;
 	bus_state->next_statechange = jiffies + msecs_to_jiffies(10);