diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 40e0a0c..79ccfe5 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -116,6 +116,7 @@
 {
 	u32 command;
 	u32 state;
+	int ret;
 
 	state = xhci_readl(xhci, &xhci->op_regs->status);
 	if ((state & STS_HALT) == 0) {
@@ -130,7 +131,17 @@
 	/* XXX: Why does EHCI set this here?  Shouldn't other code do this? */
 	xhci_to_hcd(xhci)->state = HC_STATE_HALT;
 
-	return handshake(xhci, &xhci->op_regs->command, CMD_RESET, 0, 250 * 1000);
+	ret = handshake(xhci, &xhci->op_regs->command,
+			CMD_RESET, 0, 250 * 1000);
+	if (ret)
+		return ret;
+
+	xhci_dbg(xhci, "Wait for controller to be ready for doorbell rings\n");
+	/*
+	 * xHCI cannot write to any doorbells or operational registers other
+	 * than status until the "Controller Not Ready" flag is cleared.
+	 */
+	return handshake(xhci, &xhci->op_regs->status, STS_CNR, 0, 250 * 1000);
 }