unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX);
unregister_chrdev_region(USB_DEVICE_DEV, USB_DEVICE_MAX);
void usbdev_cleanup(void){	class_destroy(usb_device_class);	cdev_del(&usb_device_cdev);	unregister_chrdev_region(USB_DEVICE_MAJOR, USB_DEVICE_MAX);}