#include #include #include #include #include #include #include #include #include #include #include #include #include #define NEWCHRLED_CNT 1 #define NEWCHRLED_NAME "test" /* newchrled设备结构体 */ struct newchrled_dev{ dev_t devid; /* 设备号 */ struct cdev cdev; /* cdev */ struct class *class; /* 类 */ struct device *device; /* 设备 */ int major; /* 主设备号 */ int minor; /* 次设备号 */ }; static char read_char[]="readsuccess"; static char write_char[32]; struct newchrled_dev newchrled; /* led设备 */ static int led_open(struct inode *inode, struct file *filp) { filp->private_data = &newchrled; /* 设置私有数据 */ printk("open success\n"); return 0; } static ssize_t led_read(struct file *filp, char __user *buf, size_t cnt, loff_t *offt) { int ret; ret = copy_to_user(buf,read_char,sizeof(read_char)); if(ret == 0) printk("%s\n",read_char); else printk("readfail\n"); return 0; } static ssize_t led_write(struct file *filp, const char __user *buf, size_t cnt, loff_t *offt) { int ret; ret = copy_from_user(write_char,buf,sizeof(write_char)); if(ret == 0) printk("%s\n",write_char); else printk("writefail\n"); return 0; } static int led_release(struct inode *inode, struct file *filp) { return 0; } static long led_ioctl(struct file *filp, unsigned int cmd, unsigned long argv) { printk("open success\n"); return 0; } /* 设备操作函数 */ static struct file_operations newchrled_fops = { .owner = THIS_MODULE, .open = led_open, .read = led_read, .write = led_write, .release = led_release, .unlocked_ioctl= led_ioctl, }; static int __init led_init(void) { if (newchrled.major) { /* 定义了设备号 */ printk("newchrled.major ******************\n"); newchrled.devid = MKDEV(newchrled.major, 0); register_chrdev_region(newchrled.devid, NEWCHRLED_CNT, NEWCHRLED_NAME); } else { /* 没有定义设备号 */ alloc_chrdev_region(&newchrled.devid, 0, NEWCHRLED_CNT, NEWCHRLED_NAME); /* 申请设备号 */ newchrled.major = MAJOR(newchrled.devid); /* 获取分配号的主设备号 */ newchrled.minor = MINOR(newchrled.devid); /* 获取分配号的次设备号 */ printk("newchrled.major %d newchrled.minor %d\n",newchrled.major,newchrled.minor); } newchrled.cdev.owner = THIS_MODULE; cdev_init(&newchrled.cdev, &newchrled_fops); cdev_add(&newchrled.cdev, newchrled.devid, NEWCHRLED_CNT); newchrled.class = class_create(THIS_MODULE, NEWCHRLED_NAME); if (IS_ERR(newchrled.class)) { return PTR_ERR(newchrled.class); } newchrled.device = device_create(newchrled.class, NULL,newchrled.devid, NULL, NEWCHRLED_NAME); if (IS_ERR(newchrled.device)) { return PTR_ERR(newchrled.device); } printk("init success\n"); return 0; } static void __exit led_exit(void) { cdev_del(&newchrled.cdev);/* 删除cdev */ unregister_chrdev_region(newchrled.devid, NEWCHRLED_CNT); /* 注销设备号 */ device_destroy(newchrled.class, newchrled.devid); class_destroy(newchrled.class); printk("exit success\n"); } module_init(led_init); module_exit(led_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("luozhikun");