usb: dwc3: gadget: Return proper request status

If the user sets the usb_request's no_interrupt, then there will be no
completion event for the request. Currently the driver incorrectly uses
the event status of a different request to report the status for a
request with no_interrupt. The dwc3 driver needs to check the TRB status
associated with the request when reporting its status.

Note: this is only applicable to missed_isoc TRB completion status, but
the other status are also listed for completeness/documentation.

Fixes: 6d8a019614f3 ("usb: dwc3: gadget: check for Missed Isoc from event status")
Cc: <stable@vger.kernel.org>
Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/db2c80108286cfd108adb05bad52138b78d7c3a7.1650673655.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index ab725d2..0b9c249 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -3274,6 +3274,7 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
                const struct dwc3_event_depevt *event,
                struct dwc3_request *req, int status)
 {
+       int request_status;
        int ret;
 
        if (req->request.num_mapped_sgs)
@@ -3294,7 +3295,35 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
                req->needs_extra_trb = false;
        }
 
-       dwc3_gadget_giveback(dep, req, status);
+       /*
+        * The event status only reflects the status of the TRB with IOC set.
+        * For the requests that don't set interrupt on completion, the driver
+        * needs to check and return the status of the completed TRBs associated
+        * with the request. Use the status of the last TRB of the request.
+        */
+       if (req->request.no_interrupt) {
+               struct dwc3_trb *trb;
+
+               trb = dwc3_ep_prev_trb(dep, dep->trb_dequeue);
+               switch (DWC3_TRB_SIZE_TRBSTS(trb->size)) {
+               case DWC3_TRBSTS_MISSED_ISOC:
+                       /* Isoc endpoint only */
+                       request_status = -EXDEV;
+                       break;
+               case DWC3_TRB_STS_XFER_IN_PROG:
+                       /* Applicable when End Transfer with ForceRM=0 */
+               case DWC3_TRBSTS_SETUP_PENDING:
+                       /* Control endpoint only */
+               case DWC3_TRBSTS_OK:
+               default:
+                       request_status = 0;
+                       break;
+               }
+       } else {
+               request_status = status;
+       }
+
+       dwc3_gadget_giveback(dep, req, request_status);
 
 out:
        return ret;