USB: WUSBCORE: clear RPIPE stall for control endpoints

When the HWA encounters a STALL on a control endpoint, it should clear the
RPIPE_STALL feature on the RPIPE before processing the next transfer
request.  Otherwise, all transfer requests on that endpoint after the
first STALL will fail because the RPIPE is still in the halted state.
This also removes the unneccessary call to spin_lock_irqsave for a nested
lock that was present in the first patch.

Signed-off-by: Thomas Pugliese <thomas.pugliese@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 74 insertions, 10 deletions

diff --git a/drivers/usb/wusbcore/wa-xfer.c b/drivers/usb/wusbcore/wa-xfer.c
index f5c81afc6e96..d74fe1ae16ac 100644
--- a/drivers/usb/wusbcore/wa-xfer.c
+++ b/drivers/usb/wusbcore/wa-xfer.c
@@ -1100,7 +1100,7 @@ error_xfer_submit:
  */
 void wa_urb_enqueue_run(struct work_struct *ws)
 {
-	struct wahc *wa = container_of(ws, struct wahc, xfer_work);
+	struct wahc *wa = container_of(ws, struct wahc, xfer_enqueue_work);
 	struct wa_xfer *xfer, *next;
 	struct urb *urb;
 	LIST_HEAD(tmp_list);
@@ -1126,6 +1126,49 @@ void wa_urb_enqueue_run(struct work_struct *ws)
 EXPORT_SYMBOL_GPL(wa_urb_enqueue_run);
 
 /*
+ * Process the errored transfers on the Wire Adapter outside of interrupt.
+ */
+void wa_process_errored_transfers_run(struct work_struct *ws)
+{
+	struct wahc *wa = container_of(ws, struct wahc, xfer_error_work);
+	struct wa_xfer *xfer, *next;
+	LIST_HEAD(tmp_list);
+
+	pr_info("%s: Run delayed STALL processing.\n", __func__);
+
+	/* Create a copy of the wa->xfer_errored_list while holding the lock */
+	spin_lock_irq(&wa->xfer_list_lock);
+	list_cut_position(&tmp_list, &wa->xfer_errored_list,
+			wa->xfer_errored_list.prev);
+	spin_unlock_irq(&wa->xfer_list_lock);
+
+	/*
+	 * run rpipe_clear_feature_stalled from temp list without list lock
+	 * held.
+	 */
+	list_for_each_entry_safe(xfer, next, &tmp_list, list_node) {
+		struct usb_host_endpoint *ep;
+		unsigned long flags;
+		struct wa_rpipe *rpipe;
+
+		spin_lock_irqsave(&xfer->lock, flags);
+		ep = xfer->ep;
+		rpipe = ep->hcpriv;
+		spin_unlock_irqrestore(&xfer->lock, flags);
+
+		/* clear RPIPE feature stalled without holding a lock. */
+		rpipe_clear_feature_stalled(wa, ep);
+
+		/* complete the xfer. This removes it from the tmp list. */
+		wa_xfer_completion(xfer);
+
+		/* check for work. */
+		wa_xfer_delayed_run(rpipe);
+	}
+}
+EXPORT_SYMBOL_GPL(wa_process_errored_transfers_run);
+
+/*
  * Submit a transfer to the Wire Adapter in a delayed way
  *
  * The process of enqueuing involves possible sleeps() [see
@@ -1180,7 +1223,7 @@ int wa_urb_enqueue(struct wahc *wa, struct usb_host_endpoint *ep,
 		spin_lock_irqsave(&wa->xfer_list_lock, my_flags);
 		list_add_tail(&xfer->list_node, &wa->xfer_delayed_list);
 		spin_unlock_irqrestore(&wa->xfer_list_lock, my_flags);
-		queue_work(wusbd, &wa->xfer_work);
+		queue_work(wusbd, &wa->xfer_enqueue_work);
 	} else {
 		wa_urb_enqueue_b(xfer);
 	}
@@ -1222,7 +1265,8 @@ int wa_urb_dequeue(struct wahc *wa, struct urb *urb)
 
 	xfer = urb->hcpriv;
 	if (xfer == NULL) {
-		/* NOthing setup yet enqueue will see urb->status !=
+		/*
+		 * Nothing setup yet enqueue will see urb->status !=
 		 * -EINPROGRESS (by hcd layer) and bail out with
 		 * error, no need to do completion
 		 */
@@ -1360,7 +1404,7 @@ static int wa_xfer_status_to_errno(u8 status)
  *
  * inbound transfers: need to schedule a DTI read
  *
- * FIXME: this functio needs to be broken up in parts
+ * FIXME: this function needs to be broken up in parts
  */
 static void wa_xfer_result_chew(struct wahc *wa, struct wa_xfer *xfer)
 {
@@ -1482,17 +1526,37 @@ error_submit_buf_in:
 	seg->result = result;
 	kfree(wa->buf_in_urb->sg);
 error_sg_alloc:
+	__wa_xfer_abort(xfer);
 error_complete:
 	seg->status = WA_SEG_ERROR;
 	xfer->segs_done++;
 	rpipe_ready = rpipe_avail_inc(rpipe);
-	__wa_xfer_abort(xfer);
 	done = __wa_xfer_is_done(xfer);
-	spin_unlock_irqrestore(&xfer->lock, flags);
-	if (done)
-		wa_xfer_completion(xfer);
-	if (rpipe_ready)
-		wa_xfer_delayed_run(rpipe);
+	/*
+	 * queue work item to clear STALL for control endpoints.
+	 * Otherwise, let endpoint_reset take care of it.
+	 */
+	if (((usb_status & 0x3f) == WA_XFER_STATUS_HALTED) &&
+		usb_endpoint_xfer_control(&xfer->ep->desc) &&
+		done) {
+
+		dev_info(dev, "Control EP stall.  Queue delayed work.\n");
+		spin_lock_irq(&wa->xfer_list_lock);
+		/* remove xfer from xfer_list. */
+		list_del(&xfer->list_node);
+		/* add xfer to xfer_errored_list. */
+		list_add_tail(&xfer->list_node, &wa->xfer_errored_list);
+		spin_unlock_irq(&wa->xfer_list_lock);
+		spin_unlock_irqrestore(&xfer->lock, flags);
+		queue_work(wusbd, &wa->xfer_error_work);
+	} else {
+		spin_unlock_irqrestore(&xfer->lock, flags);
+		if (done)
+			wa_xfer_completion(xfer);
+		if (rpipe_ready)
+			wa_xfer_delayed_run(rpipe);
+	}
+
 	return;
 
 error_bad_seg: