/* This function will initilize the usb class driver related data structure, and it should be invoked in the usb system initialization. */
rt_err_t rt_usbh_class_driver_init(void)
/* This function will initilize the usb class driver related data structure, and it should be invoked in the usb system initialization. */
rt_err_t rt_usbh_class_driver_init(void)
{
    if (_driver_list_created == RT_FALSE)
    {
        rt_list_init(&_driver_list);
        _driver_list_created = RT_TRUE;
    }
    return RT_EOK;
}