Bit shift the bmAttributes field to interpret isochronous endpoint.

device/usb/usb_device_impl.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "device/usb/usb_device_impl.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 39 matching lines @@
     case LIBUSB_ENDPOINT_OUT:
       return USB_DIRECTION_OUTBOUND;
     default:
       NOTREACHED();
       return USB_DIRECTION_INBOUND;
   }
 }
 
 UsbSynchronizationType GetSynchronizationType(
     const libusb_endpoint_descriptor* descriptor) {
-  switch (descriptor->bmAttributes & LIBUSB_ISO_SYNC_TYPE_MASK) {
+  switch ((descriptor->bmAttributes & LIBUSB_ISO_SYNC_TYPE_MASK) >> 2) {
     case LIBUSB_ISO_SYNC_TYPE_NONE:
       return USB_SYNCHRONIZATION_NONE;
     case LIBUSB_ISO_SYNC_TYPE_ASYNC:
       return USB_SYNCHRONIZATION_ASYNCHRONOUS;
     case LIBUSB_ISO_SYNC_TYPE_ADAPTIVE:
       return USB_SYNCHRONIZATION_ADAPTIVE;
     case LIBUSB_ISO_SYNC_TYPE_SYNC:
       return USB_SYNCHRONIZATION_SYNCHRONOUS;
     default:
       NOTREACHED();
@@ skipping 11 matching lines @@
       return USB_TRANSFER_BULK;
     case LIBUSB_TRANSFER_TYPE_INTERRUPT:
       return USB_TRANSFER_INTERRUPT;
     default:
       NOTREACHED();
       return USB_TRANSFER_CONTROL;
   }
 }
 
 UsbUsageType GetUsageType(const libusb_endpoint_descriptor* descriptor) {
-  switch (descriptor->bmAttributes & LIBUSB_ISO_USAGE_TYPE_MASK) {
+  switch ((descriptor->bmAttributes & LIBUSB_ISO_USAGE_TYPE_MASK) >> 4) {
     case LIBUSB_ISO_USAGE_TYPE_DATA:
       return USB_USAGE_DATA;
     case LIBUSB_ISO_USAGE_TYPE_FEEDBACK:
       return USB_USAGE_FEEDBACK;
     case LIBUSB_ISO_USAGE_TYPE_IMPLICIT:
       return USB_USAGE_EXPLICIT_FEEDBACK;
     default:
       NOTREACHED();
       return USB_USAGE_DATA;
   }
@@ skipping 296 matching lines @@
     }
   } else {
     VLOG(1) << "Failed to read device descriptor to cache string descriptors: "
             << ConvertPlatformUsbErrorToString(rv);
   }
   strings_cached_ = true;
 }
 #endif  // !defined(USE_UDEV)
 
 }  // namespace device