嵌入式linux gpio驱动程序

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/gpio.h>
#include <linux/uaccess.h>

#define DEVICE_NAME "gpio_device"
#define GPIO_PIN 18

static int gpio_major;
static struct class *gpio_class;
static struct device *gpio_device;

static ssize_t gpio_write(struct file *file, const char __user *ubuf, size_t count, loff_t *ppos) {
    char buf[1];
    if (copy_from_user(buf, ubuf, count)) {
        return -EFAULT;
    }
    if (buf[0] == '1') {
        gpio_set_value(GPIO_PIN, 1);
    } else if (buf[0] == '0') {
        gpio_set_value(GPIO_PIN, 0);
    }
    return count;
}

static struct file_operations gpio_fops = {
    .write = gpio_write,
};

static int __init gpio_init(void) {
    gpio_major = register_chrdev(0, DEVICE_NAME, &gpio_fops);
    if (gpio_major < 0) {
        printk(KERN_ALERT "Failed to register device: %d\n", gpio_major);
        return gpio_major;
    }

    gpio_class = class_create(THIS_MODULE, DEVICE_NAME);
    if (IS_ERR(gpio_class)) {
        unregister_chrdev(gpio_major, DEVICE_NAME);
        printk(KERN_ALERT "Failed to create class\n");
        return PTR_ERR(gpio_class);
    }

    gpio_device = device_create(gpio_class, NULL, MKDEV(gpio_major, 0), NULL, DEVICE_NAME);
    if (IS_ERR(gpio_device)) {
        class_destroy(gpio_class);
        unregister_chrdev(gpio_major, DEVICE_NAME);
        printk(KERN_ALERT "Failed to create device\n");
        return PTR_ERR(gpio_device);
    }

    gpio_request(GPIO_PIN, "gpio_pin");
    gpio_direction_output(GPIO_PIN, 0);

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

static void __exit gpio_exit(void) {
    device_destroy(gpio_class, MKDEV(gpio_major, 0));
    class_unregister(gpio_class);
    class_destroy(gpio_class);
    unregister_chrdev(gpio_major, DEVICE_NAME);
    gpio_free(GPIO_PIN);
    printk(KERN_INFO "GPIO Driver Removed\n");
}

module_init(gpio_init);
module_exit(gpio_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Your Name");
MODULE_DESCRIPTION("Simple GPIO Driver");
MODULE_VERSION("1.0");