diff --git a/usb/iso.go b/usb/iso.go
deleted file mode 100644
index 01a9062..0000000
--- a/usb/iso.go
+++ /dev/null
@@ -1,46 +0,0 @@
-// Copyright 2013 Google Inc.  All rights reserved.
-// Copyright 2016 the gousb Authors.  All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-//     http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package usb
-
-/*
-#include <libusb-1.0/libusb.h>
-*/
-import "C"
-
-import (
-	"log"
-	"time"
-)
-
-func isochronous_xfer(e *endpoint, buf []byte, timeout time.Duration) (int, error) {
-	t, err := e.newUSBTransfer(TRANSFER_TYPE_ISOCHRONOUS, buf)
-	if err != nil {
-		return 0, err
-	}
-	defer t.free()
-
-	if err := t.submit(timeout); err != nil {
-		log.Printf("iso: xfer failed to submit: %s", err)
-		return 0, err
-	}
-
-	n, err := t.wait(buf)
-	if err != nil {
-		log.Printf("iso: xfer failed: %s", err)
-		return 0, err
-	}
-	return n, err
-}