linux 块驱动设备驱动

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/cdev.h>
#include <linux/device.h>

static struct cdev my_cdev;
static struct class *my_class;

static int my_open(struct inode *inode, struct file *file) {
    printk(KERN_INFO "Device opened\n");
    return 0;
}

static int my_release(struct inode *inode, struct file *file) {
    printk(KERN_INFO "Device closed\n");
    return 0;
}

static ssize_t my_read(struct file *file, char __user *ubuf, size_t count, loff_t *ppos) {
    printk(KERN_INFO "Read operation\n");
    return 0;
}

static ssize_t my_write(struct file *file, const char __user *ubuf, size_t count, loff_t *ppos) {
    printk(KERN_INFO "Write operation\n");
    return 0;
}

static struct file_operations fops = {
    .open = my_open,
    .release = my_release,
    .read = my_read,
    .write = my_write,
};

static int __init my_init(void) {
    int ret;
    dev_t dev_num;

    ret = alloc_chrdev_region(&dev_num, 0, 1, "my_device");
    if (ret < 0)
        return ret;

    cdev_init(&my_cdev, &fops);
    my_cdev.owner = THIS_MODULE;
    ret = cdev_add(&my_cdev, dev_num, 1);
    if (ret < 0)
        return ret;

    my_class = class_create(THIS_MODULE, "my_device_class");
    if (IS_ERR(my_class))
        return PTR_ERR(my_class);

    device_create(my_class, NULL, dev_num, NULL, "my_device");

    printk(KERN_INFO "Driver registered\n");
    return 0;
}

static void __exit my_exit(void) {
    dev_t dev_num = my_cdev.dev;

    device_destroy(my_class, dev_num);
    class_unregister(my_class);
    class_destroy(my_class);
    cdev_del(&my_cdev);
    unregister_chrdev_region(dev_num, 1);

    printk(KERN_INFO "Driver unregistered\n");
}

module_init(my_init);
module_exit(my_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Your Name");
MODULE_DESCRIPTION("A simple block device driver");