3 files changed, 31 insertions, 39 deletions

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 0ed64eb68e48..dff9b5ead3b3 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -550,6 +550,7 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
 	struct xhci_generic_trb *trb;
 	struct xhci_ep_ctx *ep_ctx;
 	dma_addr_t addr;
+	u64 hw_dequeue;
 
 	ep_ring = xhci_triad_to_transfer_ring(xhci, slot_id,
 			ep_index, stream_id);
@@ -559,56 +560,57 @@ void xhci_find_new_dequeue_state(struct xhci_hcd *xhci,
 				stream_id);
 		return;
 	}
-	state->new_cycle_state = 0;
-	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
-			"Finding segment containing stopped TRB.");
-	state->new_deq_seg = find_trb_seg(cur_td->start_seg,
-			dev->eps[ep_index].stopped_trb,
-			&state->new_cycle_state);
-	if (!state->new_deq_seg) {
-		WARN_ON(1);
-		return;
-	}
 
 	/* Dig out the cycle state saved by the xHC during the stop ep cmd */
 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 			"Finding endpoint context");
 	ep_ctx = xhci_get_ep_ctx(xhci, dev->out_ctx, ep_index);
-	state->new_cycle_state = 0x1 & le64_to_cpu(ep_ctx->deq);
+	hw_dequeue = le64_to_cpu(ep_ctx->deq);
+
+	/* Find virtual address and segment of hardware dequeue pointer */
+	state->new_deq_seg = ep_ring->deq_seg;
+	state->new_deq_ptr = ep_ring->dequeue;
+	while (xhci_trb_virt_to_dma(state->new_deq_seg, state->new_deq_ptr)
+			!= (dma_addr_t)(hw_dequeue & ~0xf)) {
+		next_trb(xhci, ep_ring, &state->new_deq_seg,
+					&state->new_deq_ptr);
+		if (state->new_deq_ptr == ep_ring->dequeue) {
+			WARN_ON(1);
+			return;
+		}
+	}
+	/*
+	 * Find cycle state for last_trb, starting at old cycle state of
+	 * hw_dequeue. If there is only one segment ring, find_trb_seg() will
+	 * return immediately and cannot toggle the cycle state if this search
+	 * wraps around, so add one more toggle manually in that case.
+	 */
+	state->new_cycle_state = hw_dequeue & 0x1;
+	if (ep_ring->first_seg == ep_ring->first_seg->next &&
+			cur_td->last_trb < state->new_deq_ptr)
+		state->new_cycle_state ^= 0x1;
 
 	state->new_deq_ptr = cur_td->last_trb;
 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 			"Finding segment containing last TRB in TD.");
 	state->new_deq_seg = find_trb_seg(state->new_deq_seg,
-			state->new_deq_ptr,
-			&state->new_cycle_state);
+			state->new_deq_ptr, &state->new_cycle_state);
 	if (!state->new_deq_seg) {
 		WARN_ON(1);
 		return;
 	}
 
+	/* Increment to find next TRB after last_trb. Cycle if appropriate. */
 	trb = &state->new_deq_ptr->generic;
 	if (TRB_TYPE_LINK_LE32(trb->field[3]) &&
 	    (trb->field[3] & cpu_to_le32(LINK_TOGGLE)))
 		state->new_cycle_state ^= 0x1;
 	next_trb(xhci, ep_ring, &state->new_deq_seg, &state->new_deq_ptr);
 
-	/*
-	 * If there is only one segment in a ring, find_trb_seg()'s while loop
-	 * will not run, and it will return before it has a chance to see if it
-	 * needs to toggle the cycle bit.  It can't tell if the stalled transfer
-	 * ended just before the link TRB on a one-segment ring, or if the TD
-	 * wrapped around the top of the ring, because it doesn't have the TD in
-	 * question.  Look for the one-segment case where stalled TRB's address
-	 * is greater than the new dequeue pointer address.
-	 */
-	if (ep_ring->first_seg == ep_ring->first_seg->next &&
-			state->new_deq_ptr < dev->eps[ep_index].stopped_trb)
-		state->new_cycle_state ^= 0x1;
+	/* Don't update the ring cycle state for the producer (us). */
 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 			"Cycle state = 0x%x", state->new_cycle_state);
 
-	/* Don't update the ring cycle state for the producer (us). */
 	xhci_dbg_trace(xhci, trace_xhci_dbg_cancel_urb,
 			"New dequeue segment = %p (virtual)",
 			state->new_deq_seg);
@@ -791,7 +793,6 @@ static void xhci_handle_cmd_stop_ep(struct xhci_hcd *xhci, int slot_id,
 	if (list_empty(&ep->cancelled_td_list)) {
 		xhci_stop_watchdog_timer_in_irq(xhci, ep);
 		ep->stopped_td = NULL;
-		ep->stopped_trb = NULL;
 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
 		return;
 	}
@@ -859,11 +860,9 @@ remove_finished_td:
 		ring_doorbell_for_active_rings(xhci, slot_id, ep_index);
 	}
 
-	/* Clear stopped_td and stopped_trb if endpoint is not halted */
-	if (!(ep->ep_state & EP_HALTED)) {
+	/* Clear stopped_td 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.
@@ -1908,14 +1907,12 @@ static void xhci_cleanup_halted_endpoint(struct xhci_hcd *xhci,
 	struct xhci_virt_ep *ep = &xhci->devs[slot_id]->eps[ep_index];
 	ep->ep_state |= EP_HALTED;
 	ep->stopped_td = td;
-	ep->stopped_trb = event_trb;
 	ep->stopped_stream = stream_id;
 
 	xhci_queue_reset_ep(xhci, slot_id, ep_index);
 	xhci_cleanup_stalled_ring(xhci, td->urb->dev, ep_index);
 
 	ep->stopped_td = NULL;
-	ep->stopped_trb = NULL;
 	ep->stopped_stream = 0;
 
 	xhci_ring_cmd_db(xhci);
@@ -1997,7 +1994,6 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_td *td,
 		 * the ring dequeue pointer or take this TD off any lists yet.
 		 */
 		ep->stopped_td = td;
-		ep->stopped_trb = event_trb;
 		return 0;
 	} else {
 		if (trb_comp_code == COMP_STALL) {
@@ -2009,7 +2005,6 @@ static int finish_td(struct xhci_hcd *xhci, struct xhci_td *td,
 			 * USB class driver clear the stall later.
 			 */
 			ep->stopped_td = td;
-			ep->stopped_trb = event_trb;
 			ep->stopped_stream = ep_ring->stream_id;
 		} else if (xhci_requires_manual_halt_cleanup(xhci,
 					ep_ctx, trb_comp_code)) {
@@ -2626,7 +2621,7 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 				 * successful event after a short transfer.
 				 * Ignore it.
 				 */
-				if ((xhci->quirks & XHCI_SPURIOUS_SUCCESS) && 
+				if ((xhci->quirks & XHCI_SPURIOUS_SUCCESS) &&
 						ep_ring->last_td_was_short) {
 					ep_ring->last_td_was_short = false;
 					ret = 0;
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index b57a17521b53..cca289667cf6 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -2933,7 +2933,6 @@ void xhci_endpoint_reset(struct usb_hcd *hcd,
 		xhci_ring_cmd_db(xhci);
 	}
 	virt_ep->stopped_td = NULL;
-	virt_ep->stopped_trb = NULL;
 	virt_ep->stopped_stream = 0;
 	spin_unlock_irqrestore(&xhci->lock, flags);
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 58ed9d088e63..8faef64371c6 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -864,8 +864,6 @@ struct xhci_virt_ep {
 #define EP_GETTING_NO_STREAMS	(1 << 5)
 	/* ----  Related to URB cancellation ---- */
 	struct list_head	cancelled_td_list;
-	/* The TRB that was last reported in a stopped endpoint ring */
-	union xhci_trb		*stopped_trb;
 	struct xhci_td		*stopped_td;
 	unsigned int		stopped_stream;
 	/* Watchdog timer for stop endpoint command to cancel URBs */