static void __devexit rmi4_char_dev_exit(void)
{
    pr_info("Unregistering function %s from RMI4 bus\n",
            rmi4_char_dev.drv.name);
    rmi4_bus_unregister_function_driver(&rmi4_char_dev);
}
static void __devexit rmi4_f01_exit(void)
{
	pr_info("%s Unregistering function %s\n", __func__, rmi4_f01.drv.name);
	rmi4_bus_unregister_function_driver(&rmi4_f01);
}