1 files changed, 32 insertions, 7 deletions

diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 79ccfe5f8ad0..8a49c6716b69 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -106,6 +106,33 @@ int xhci_halt(struct xhci_hcd *xhci)
 }
 
 /*
+ * Set the run bit and wait for the host to be running.
+ */
+int xhci_start(struct xhci_hcd *xhci)
+{
+	u32 temp;
+	int ret;
+
+	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	temp |= (CMD_RUN);
+	xhci_dbg(xhci, "// Turn on HC, cmd = 0x%x.\n",
+			temp);
+	xhci_writel(xhci, temp, &xhci->op_regs->command);
+
+	/*
+	 * Wait for the HCHalted Status bit to be 0 to indicate the host is
+	 * running.
+	 */
+	ret = handshake(xhci, &xhci->op_regs->status,
+			STS_HALT, 0, XHCI_MAX_HALT_USEC);
+	if (ret == -ETIMEDOUT)
+		xhci_err(xhci, "Host took too long to start, "
+				"waited %u microseconds.\n",
+				XHCI_MAX_HALT_USEC);
+	return ret;
+}
+
+/*
  * Reset a halted HC, and set the internal HC state to HC_STATE_HALT.
  *
  * This resets pipelines, timers, counters, state machines, etc.
@@ -460,13 +487,11 @@ int xhci_run(struct usb_hcd *hcd)
 	if (NUM_TEST_NOOPS > 0)
 		doorbell = xhci_setup_one_noop(xhci);
 
-	temp = xhci_readl(xhci, &xhci->op_regs->command);
-	temp |= (CMD_RUN);
-	xhci_dbg(xhci, "// Turn on HC, cmd = 0x%x.\n",
-			temp);
-	xhci_writel(xhci, temp, &xhci->op_regs->command);
-	/* Flush PCI posted writes */
-	temp = xhci_readl(xhci, &xhci->op_regs->command);
+	if (xhci_start(xhci)) {
+		xhci_halt(xhci);
+		return -ENODEV;
+	}
+
 	xhci_dbg(xhci, "// @%p = 0x%x\n", &xhci->op_regs->command, temp);
 	if (doorbell)
 		(*doorbell)(xhci);