Merge tag 'for-usb-linus-2013-09-23' of git://git.kernel.org/pub/scm/linux/kernel/git/sarah/xhci into usb-linus

Sarah writes:

xhci: Bug fixes for 3.12.

Hi Greg,

Here's five bug fixes for 3.12.

The first two bugs fix issues with the command cancellation handling,
which can lead to oopses or the xHCI driver attempting to handle
previously-completed transfers.  People have been running into oopses
and odd behavior with command cancellation for a couple kernel releases,
so they're marked for stable.

The third patch fixes an issue with USB remote wakeup under xHCI that
can only be reproduced under ChromeOS.  As discussed, this fix is not
urgent, and isn't marked for stable.

The fourth patch fixes a race condition between URB cancellation and
userspace clearing an endpoint stall.  The fifth patch removes some
annoying dmesg spam when a USB 3.0 device is disconnected, by avoiding
sending a Set SEL request.

Sarah Sharp

1 files changed, 35 insertions, 2 deletions

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 411da1fc7ae8..6bfbd80ec2b9 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -123,6 +123,16 @@ static int enqueue_is_link_trb(struct xhci_ring *ring)
 	return TRB_TYPE_LINK_LE32(link->control);
 }
 
+union xhci_trb *xhci_find_next_enqueue(struct xhci_ring *ring)
+{
+	/* Enqueue pointer can be left pointing to the link TRB,
+	 * we must handle that
+	 */
+	if (TRB_TYPE_LINK_LE32(ring->enqueue->link.control))
+		return ring->enq_seg->next->trbs;
+	return ring->enqueue;
+}
+
 /* Updates trb to point to the next TRB in the ring, and updates seg if the next
  * TRB is in a new segment.  This does not skip over link TRBs, and it does not
  * effect the ring dequeue or enqueue pointers.
@@ -859,8 +869,12 @@ remove_finished_td:
 		/* Otherwise ring the doorbell(s) to restart queued transfers */
 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
 	}
-	ep->stopped_td = NULL;
-	ep->stopped_trb = NULL;
+
+	/* Clear stopped_td and stopped_trb if endpoint is not halted */
+	if (!(ep->ep_state & EP_HALTED)) {
+		ep->stopped_td = NULL;
+		ep->stopped_trb = NULL;
+	}
 
 	/*
 	 * Drop the lock and complete the URBs in the cancelled TD list.
@@ -1414,6 +1428,12 @@ static void handle_cmd_completion(struct xhci_hcd *xhci,
 			inc_deq(xhci, xhci->cmd_ring);
 			return;
 		}
+		/* There is no command to handle if we get a stop event when the
+		 * command ring is empty, event->cmd_trb points to the next
+		 * unset command
+		 */
+		if (xhci->cmd_ring->dequeue == xhci->cmd_ring->enqueue)
+			return;
 	}
 
 	switch (le32_to_cpu(xhci->cmd_ring->dequeue->generic.field[3])
@@ -1743,6 +1763,19 @@ static void handle_port_status(struct xhci_hcd *xhci,
 		}
 	}
 
+	/*
+	 * Check to see if xhci-hub.c is waiting on RExit to U0 transition (or
+	 * RExit to a disconnect state).  If so, let the the driver know it's
+	 * out of the RExit state.
+	 */
+	if (!DEV_SUPERSPEED(temp) &&
+			test_and_clear_bit(faked_port_index,
+				&bus_state->rexit_ports)) {
+		complete(&bus_state->rexit_done[faked_port_index]);
+		bogus_port_status = true;
+		goto cleanup;
+	}
+
 	if (hcd->speed != HCD_USB3)
 		xhci_test_and_clear_bit(xhci, port_array, faked_port_index,
 					PORT_PLC);