Merge remote-tracking branch 'remotes/kraxel/tags/pull-usb-20150303-1' into staging

xhci: generate a Transfer Event for each Transfer TRB with the IOC bit set

# gpg: Signature made Tue Mar  3 07:38:43 2015 GMT using RSA key ID D3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"

* remotes/kraxel/tags/pull-usb-20150303-1:
  xhci: generate a Transfer Event for each Transfer TRB with the IOC bit set
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

hw/usb/hcd-xhci.c

@@ -1767,9 +1767,18 @@ static void xhci_xfer_report(XHCITransfer *xfer)
             break;
         }
 
-        if (!reported && ((trb->control & TRB_TR_IOC) ||
-                          (shortpkt && (trb->control & TRB_TR_ISP)) ||
-                          (xfer->status != CC_SUCCESS && left == 0))) {
+        /*
+         * XHCI 1.1, 4.11.3.1 Transfer Event TRB -- "each Transfer TRB
+         * encountered with its IOC flag set to '1' shall generate a Transfer
+         * Event."
+         *
+         * Otherwise, longer transfers can have multiple data TRBs (for scatter
+         * gather). Short transfers and errors should be reported once per
+         * transfer only.
+         */
+        if ((trb->control & TRB_TR_IOC) ||
+            (!reported && ((shortpkt && (trb->control & TRB_TR_ISP)) ||
+                           (xfer->status != CC_SUCCESS && left == 0)))) {
             event.slotid = xfer->slotid;
             event.epid = xfer->epid;
             event.length = (trb->status & 0x1ffff) - chunk;