#include <linux/init.h> //for module_init #include <linux/module.h> //for printk #include <asm-generic/errno-base.h> #include <linux/fs.h> #include <asm-generic/uaccess.h> #include <asm/io.h> #include <linux/cdev.h> #include <linux/device.h> /*定義一個cdev物件*/ struct cdev test_cdev; struct class *test_class; //裝置類 struct device *test_device; //裝置檔案 unsigned int major = 0; unsigned int minor = 0; unsigned int devno = 0; int test_open(struct inode *inode, struct file *file) { printk("%s\n",__FUNCTION__); return 0; } struct file_operations test_fops = { .owner = THIS_MODULE, //屬於本模組 .open = test_open, }; static int test_init(void) { int ret; int errno; /*獲取裝置號*/ devno = MKDEV(major,minor); if(major) { /*1.靜態申請裝置號*/ ret = register_chrdev_region(devno,1,"test-new-driver"); if(ret){ printk("register chrdev region failed\n"); errno = -EBUSY; goto err; } } else { /*動態申請裝置號*/ ret = alloc_chrdev_region(&devno,0,1,"test-new-driver"); if(ret){ printk("register chrdev alloc region failed\n"); errno = -EBUSY; goto err; } } /*初始化一個cdev物件*/ cdev_init(&test_cdev,&test_fops); /*使用(此時真正的註冊進核心地址表)*/ ret = cdev_add(&test_cdev,devno,1); if(ret){ printk("cdev add failed\n"); errno = -EBUSY; goto err1; } /*動態的建立裝置檔案*/ test_class = class_create(THIS_MODULE,"test_module"); if(IS_ERR(test_class)){ printk("class_create failed\n"); errno = PTR_ERR(test_class); goto err2; } /*5.申請建立一個裝置檔案*/ test_device = device_create(test_class,NULL,devno,NULL,"test"); if(IS_ERR(test_device)){ printk("device create failed\n"); errno = PTR_ERR(test_device); goto err3; } return 0; err3: class_destroy(test_class); err2: cdev_del(&test_cdev); err1: unregister_chrdev_region(devno,1); err: return errno; } static void test_exit(void) { device_destroy(test_class,devno); class_destroy(test_class); cdev_del(&test_cdev); unregister_chrdev_region(devno,1); printk("bye!\n"); } module_init(test_init); module_exit(test_exit); MODULE_LICENSE("GPL"); ========================上為驅動，下為應用======================= #include <sys/types.h> #include <stdio.h> int main(int argc,char *argv[]) { int fd; /*開啟檔案*/ fd = open("/dev/test

",O_RDWR); if(fd < 0){ perror("open"); return -1; } printf("\nopen success... [%d]\n",fd); return 0; }