[PATCH v4 2/6] usb: dwc3: gadget: cancel requests instead of release after missed isoc

[Dan Vacura]

From: Jeff Vanhoof <qjv001@xxxxxxxxxxxx>

arm-smmu related crashes seen after a Missed ISOC interrupt when
no_interrupt=1 is used. This can happen if the hardware is still using
the data associated with a TRB after the usb_request's ->complete call
has been made.  Instead of immediately releasing a request when a Missed
ISOC interrupt has occurred, this change will add logic to cancel the
request instead where it will eventually be released when the
END_TRANSFER command has completed. This logic is similar to some of the
cleanup done in dwc3_gadget_ep_dequeue.

Fixes: 6d8a019614f3 ("usb: dwc3: gadget: check for Missed Isoc from event status")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Jeff Vanhoof <qjv001@xxxxxxxxxxxx>
Co-developed-by: Dan Vacura <w36195@xxxxxxxxxxxx>
Signed-off-by: Dan Vacura <w36195@xxxxxxxxxxxx>
---
V1 -> V3:
- no change, new patch in series
V3 -> V4:
- no change

 drivers/usb/dwc3/core.h   |  1 +
 drivers/usb/dwc3/gadget.c | 38 ++++++++++++++++++++++++++------------
 2 files changed, 27 insertions(+), 12 deletions(-)

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 8f9959ba9fd4..9b005d912241 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -943,6 +943,7 @@ struct dwc3_request {
 #define DWC3_REQUEST_STATUS_DEQUEUED		3
 #define DWC3_REQUEST_STATUS_STALLED		4
 #define DWC3_REQUEST_STATUS_COMPLETED		5
+#define DWC3_REQUEST_STATUS_MISSED_ISOC		6
 #define DWC3_REQUEST_STATUS_UNKNOWN		-1
 
 	u8			epnum;
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 079cd333632e..411532c5c378 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2021,6 +2021,9 @@ static void dwc3_gadget_ep_cleanup_cancelled_requests(struct dwc3_ep *dep)
 		case DWC3_REQUEST_STATUS_STALLED:
 			dwc3_gadget_giveback(dep, req, -EPIPE);
 			break;
+		case DWC3_REQUEST_STATUS_MISSED_ISOC:
+			dwc3_gadget_giveback(dep, req, -EXDEV);
+			break;
 		default:
 			dev_err(dwc->dev, "request cancelled with wrong reason:%d\n", req->status);
 			dwc3_gadget_giveback(dep, req, -ECONNRESET);
@@ -3402,21 +3405,32 @@ static bool dwc3_gadget_endpoint_trbs_complete(struct dwc3_ep *dep,
 	struct dwc3		*dwc = dep->dwc;
 	bool			no_started_trb = true;
 
-	dwc3_gadget_ep_cleanup_completed_requests(dep, event, status);
+	if (status == -EXDEV) {
+		struct dwc3_request *tmp;
+		struct dwc3_request *req;
 
-	if (dep->flags & DWC3_EP_END_TRANSFER_PENDING)
-		goto out;
+		if (!(dep->flags & DWC3_EP_END_TRANSFER_PENDING))
+			dwc3_stop_active_transfer(dep, true, true);
 
-	if (!dep->endpoint.desc)
-		return no_started_trb;
+		list_for_each_entry_safe(req, tmp, &dep->started_list, list)
+			dwc3_gadget_move_cancelled_request(req,
+					DWC3_REQUEST_STATUS_MISSED_ISOC);
+	} else {
+		dwc3_gadget_ep_cleanup_completed_requests(dep, event, status);
 
-	if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
-		list_empty(&dep->started_list) &&
-		(list_empty(&dep->pending_list) || status == -EXDEV))
-		dwc3_stop_active_transfer(dep, true, true);
-	else if (dwc3_gadget_ep_should_continue(dep))
-		if (__dwc3_gadget_kick_transfer(dep) == 0)
-			no_started_trb = false;
+		if (dep->flags & DWC3_EP_END_TRANSFER_PENDING)
+			goto out;
+
+		if (!dep->endpoint.desc)
+			return no_started_trb;
+
+		if (usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
+			list_empty(&dep->started_list) && list_empty(&dep->pending_list))
+			dwc3_stop_active_transfer(dep, true, true);
+		else if (dwc3_gadget_ep_should_continue(dep))
+			if (__dwc3_gadget_kick_transfer(dep) == 0)
+				no_started_trb = false;
+	}
 
 out:
 	/*
-- 
2.34.1