diff --git a/reactos/drivers/usb/miniport/common/usbcommon_types.h b/reactos/drivers/usb/miniport/common/usbcommon_types.h
index f5e499284cf..6b25d233db1 100644
--- a/reactos/drivers/usb/miniport/common/usbcommon_types.h
+++ b/reactos/drivers/usb/miniport/common/usbcommon_types.h
@@ -26,7 +26,7 @@ typedef struct _USBMP_DEVICE_EXTENSTION
    ULONG BaseAddrLength;
    ULONG Flags;
    //ULONG AdapterInterfaceType;
-   //ULONG SystemIoBusNumber;
+   ULONG SystemIoBusNumber;
    ULONG SystemIoSlotNumber;
    //LIST_ENTRY AddressMappingListHead;