本篇文章记录字符设备的驱动框架：
1.定义cdev接口体和class结构体
#define HELLO_CNT 2 static int major = 0;//主设备号为0，需要让系统自动生成主设备号 static struct cdev hello_cdev; static struct class *cls;
struct file_operations hello_fops = { .owner = THIS_MODULE, .open = hello_open, }; static int hello_open(struct inode *inode, struct file *file) { printk("hello_open\n"); return 0; }
3.注册
dev_t devid; if (major) { /* 主设备号已确定 */ devid = MKDEV(major, 0); register_chrdev_region(devid, HELLO_CNT, "hello"); } else { /* 主设备号为0，让系统自动为我们分配主设备号 */ alloc_chrdev_region(&devid, 0, HELLO_CNT, "hello"); major = MAJOR(devid); } cdev_init(&hello_cdev, &hello_fops); cdev_add(&hello_cdev, devid, HELLO_CNT);
cls = class_create(THIS_MODULE, "hello"); device_create(cls, NULL, MKDEV(major, 0), NULL, "hello0");// /dev/hello0 device_create(cls, NULL, MKDEV(major, 1), NULL, "hello1");// /dev/hello1
原文：http://www.cnblogs.com/zpehome/p/3811154.html