Only set the status of a completed xfer just before giving it back to

the stack.  This will allow stricter checks when aborting transfers.

While here update a comment about short transfer and multi-TRB TD since
bulk transfers can also use a chain now.

diff --git a/sys/dev/usb/xhci.c b/sys/dev/usb/xhci.c
index 7f50578..b2f4a3c 100644 (file)
--- a/sys/dev/usb/xhci.c
+++ b/sys/dev/usb/xhci.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: xhci.c,v 1.50 2015/01/02 18:06:25 mpi Exp $ */
+/* $OpenBSD: xhci.c,v 1.51 2015/01/04 20:10:08 mpi Exp $ */
 
 /*
  * Copyright (c) 2014 Martin Pieuchot
@@ -744,29 +744,28 @@ xhci_event_xfer(struct xhci_softc *sc, uint64_t paddr, uint32_t status,
        switch (code) {
        case XHCI_CODE_SUCCESS:
                /*
-                * This might be the ``Event Status TRB'' of a control
-                * request for which the ``Event Data TRB'' triggered
-                * a Short Transfer condition, see below.
+                * This might be the last TRB of a TD that ended up
+                * with a Short Transfer condition, see below.
                 */
-               if (xfer->actlen)
-                       break;
+               if (xfer->actlen == 0)
+                       xfer->actlen = xfer->length - remain;
 
-               /* FALLTHROUGH */
+               xfer->status = USBD_NORMAL_COMPLETION;
+               break;
        case XHCI_CODE_SHORT_XFER:
                xfer->actlen = xfer->length - remain;
-               xfer->status = USBD_NORMAL_COMPLETION;
 
                /*
                 * If this is not the last TRB of a transfer, we should
-                * not assume the USB packet is finished.  In the case
-                * of a Sort Transfer condition we should theoretically
-                * clear the IOC flags on the ``Event Status TRB'' but
-                * the HC might have already processed it since before
-                * we start processing the softinterrupt.
+                * theoretically clear the IOC at the end of the chain
+                * but the HC might have already processed it before we
+                * had a change to schedule the softinterrupt.
                 */
                xx = (struct xhci_xfer *)xfer;
                if (xx->index != trb_idx)
                        return;
+
+               xfer->status = USBD_NORMAL_COMPLETION;
                break;
        case XHCI_CODE_TXERR:
        case XHCI_CODE_SPLITERR: