1 files changed, 28 insertions, 1 deletions

diff --git a/drivers/usb/host/xhci-hcd.c b/drivers/usb/host/xhci-hcd.c
index 99911e727e0b..932f99938481 100644
--- a/drivers/usb/host/xhci-hcd.c
+++ b/drivers/usb/host/xhci-hcd.c
@@ -335,6 +335,12 @@ void xhci_event_ring_work(unsigned long arg)
 	spin_lock_irqsave(&xhci->lock, flags);
 	temp = xhci_readl(xhci, &xhci->op_regs->status);
 	xhci_dbg(xhci, "op reg status = 0x%x\n", temp);
+	if (temp == 0xffffffff) {
+		xhci_dbg(xhci, "HW died, polling stopped.\n");
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		return;
+	}
+
 	temp = xhci_readl(xhci, &xhci->ir_set->irq_pending);
 	xhci_dbg(xhci, "ir_set 0 pending = 0x%x\n", temp);
 	xhci_dbg(xhci, "No-op commands handled = %d\n", xhci->noops_handled);
@@ -776,6 +782,7 @@ int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 {
 	unsigned long flags;
 	int ret;
+	u32 temp;
 	struct xhci_hcd *xhci;
 	struct xhci_td *td;
 	unsigned int ep_index;
@@ -788,6 +795,17 @@ int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 	ret = usb_hcd_check_unlink_urb(hcd, urb, status);
 	if (ret || !urb->hcpriv)
 		goto done;
+	temp = xhci_readl(xhci, &xhci->op_regs->status);
+	if (temp == 0xffffffff) {
+		xhci_dbg(xhci, "HW died, freeing TD.\n");
+		td = (struct xhci_td *) urb->hcpriv;
+
+		usb_hcd_unlink_urb_from_ep(hcd, urb);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		usb_hcd_giveback_urb(xhci_to_hcd(xhci), urb, -ESHUTDOWN);
+		kfree(td);
+		return ret;
+	}
 
 	xhci_dbg(xhci, "Cancel URB %p\n", urb);
 	xhci_dbg(xhci, "Event ring:\n");
@@ -877,7 +895,7 @@ int xhci_drop_endpoint(struct usb_hcd *hcd, struct usb_device *udev,
 	ctrl_ctx->drop_flags |= drop_flag;
 	new_drop_flags = ctrl_ctx->drop_flags;
 
-	ctrl_ctx->add_flags = ~drop_flag;
+	ctrl_ctx->add_flags &= ~drop_flag;
 	new_add_flags = ctrl_ctx->add_flags;
 
 	last_ctx = xhci_last_valid_endpoint(ctrl_ctx->add_flags);
@@ -1410,11 +1428,20 @@ void xhci_free_dev(struct usb_hcd *hcd, struct usb_device *udev)
 {
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
 	unsigned long flags;
+	u32 state;
 
 	if (udev->slot_id == 0)
 		return;
 
 	spin_lock_irqsave(&xhci->lock, flags);
+	/* Don't disable the slot if the host controller is dead. */
+	state = xhci_readl(xhci, &xhci->op_regs->status);
+	if (state == 0xffffffff) {
+		xhci_free_virt_device(xhci, udev->slot_id);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		return;
+	}
+
 	if (xhci_queue_slot_control(xhci, TRB_DISABLE_SLOT, udev->slot_id)) {
 		spin_unlock_irqrestore(&xhci->lock, flags);
 		xhci_dbg(xhci, "FIXME: allocate a command ring segment\n");