SPIDEV_MAJOR
spidev->devt = MKDEV(SPIDEV_MAJOR, minor);
status = register_chrdev(SPIDEV_MAJOR, "spi", &spidev_fops);
unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);
unregister_chrdev(SPIDEV_MAJOR, spidev_spi_driver.driver.name);