test of programlisting static int io = 0x320; int __init myradio_init(struct video_init *v) { if(check_region(io, MY_IO_SIZE)) { printk(KERN_ERR "myradio: port 0x%03X is in use.\n", io); return -EBUSY; } if(video_device_register(&my_radio, VFL_TYPE_RADIO)==-1) return -EINVAL; request_region(io, MY_IO_SIZE, "myradio"); return 0; }