static int __init init_mtdchar(void)
{
//为了兼容以前的方案,要注册mtdchar的主设备号、设备名以及fops
if (register_chrdev(MTD_CHAR_MAJOR, "mtd", &mtd_fops))
{
printk(KERN_NOTICE "Can't allocate major number %d for Memory Technology Devices.\n",
MTD_CHAR_MAJOR);
return -EAGAIN;
}