Check for either async or sync libusb error message for timeout.
diff --git a/usbutils.c b/usbutils.c
index e6e2c98..ddfc079 100644
--- a/usbutils.c
+++ b/usbutils.c
@@ -2125,6 +2125,7 @@ static void stats(struct cgpu_info *cgpu, struct timeval *tv_start, struct timev
case LIBUSB_SUCCESS:
item = CMD_CMD;
break;
+ case LIBUSB_TRANSFER_TIMED_OUT:
case LIBUSB_ERROR_TIMEOUT:
item = CMD_TIMEOUT;
break;