src/usb_libusb10.c: slightly smarter isoc error handling.

Unless we get LIBUSB_TRANSFER_NO_DEVICE or LIBUSB_TRANSFER_CANCELLED, we really
should resubmit unsucessful transfers, or eventually all of them will error and
we won't stream any transfers anymore.  We should also correctly track the
number of dead transfers if we fail to submit a transfer.

Fixes OpenKinect#227.

Signed-off-by: Drew Fisher <[email protected]>

Author: zarvox

src/usb_libusb10.c

@@ -273,17 +273,46 @@ static void iso_callback(struct libusb_transfer *xfer)
 		return;
 	}
 
-	if(xfer->status == LIBUSB_TRANSFER_COMPLETED) {
-		uint8_t *buf = (uint8_t*)xfer->buffer;
-		for (i=0; i<strm->pkts; i++) {
-			strm->cb(strm->parent->parent, buf, xfer->iso_packet_desc[i].actual_length);
-			buf += strm->len;
+	switch(xfer->status) {
+		case LIBUSB_TRANSFER_COMPLETED: // Normal operation.
+		{
+			uint8_t *buf = (uint8_t*)xfer->buffer;
+			for (i=0; i<strm->pkts; i++) {
+				strm->cb(strm->parent->parent, buf, xfer->iso_packet_desc[i].actual_length);
+				buf += strm->len;
+			}
+			libusb_submit_transfer(xfer);
+			break;
+		}
+		case LIBUSB_TRANSFER_NO_DEVICE:
+		{
+			// We lost the device we were talking to.  This is a large problem,
+			// and one that we should eventually come up with a way to
+			// properly propagate up to the caller.
+			freenect_context *ctx = strm->parent->parent->parent;
+			FN_ERROR("USB device disappeared, cancelling stream :(\n");
+			strm->dead_xfers++;
+			fnusb_stop_iso(strm->parent, strm);
+			break;
+		}
+		case LIBUSB_TRANSFER_CANCELLED:
+		{
+			freenect_context *ctx = strm->parent->parent->parent;
+			FN_SPEW("EP %02x transfer cancelled\n", xfer->endpoint);
+			strm->dead_xfers++;
+			break;
+		}
+		default:
+		{
+			// On other errors, resubmit the transfer - in particular, libusb
+			// on OSX tends to hit random errors a lot.  If we don't resubmit
+			// the transfers, eventually all of them die and then we don't get
+			// any more data from the Kinect.
+			freenect_context *ctx = strm->parent->parent->parent;
+			FN_WARNING("Isochronous transfer error: %d\n", xfer->status);
+			libusb_submit_transfer(xfer);
+			break;
 		}
-		libusb_submit_transfer(xfer);
-	} else {
-		freenect_context *ctx = strm->parent->parent->parent;
-		FN_WARNING("Isochronous transfer error: %d\n", xfer->status);
-		strm->dead_xfers++;
 	}
 }
 
@@ -313,8 +342,10 @@ int fnusb_start_iso(fnusb_dev *dev, fnusb_isoc_stream *strm, fnusb_iso_cb cb, in
 		libusb_set_iso_packet_lengths(strm->xfers[i], len);
 
 		ret = libusb_submit_transfer(strm->xfers[i]);
-		if (ret < 0)
+		if (ret < 0) {
 			FN_WARNING("Failed to submit isochronous transfer %d: %d\n", i, ret);
+			strm->dead_xfers++;
+		}
 
 		bufp += pkts*len;
 	}