DEVICE_INT_ATTR 声明一个 int属性，不用自己写show 和store 函数。
以下是演示代码：

#include <linux/uaccess.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/kernel_stat.h>
#include <linux/platform_device.h>
#include <linux/kobject.h>
#include <linux/sysfs.h>

struct device *dev;
struct kobject *root;

int version = 159;
int a = 1024;

static DEVICE_INT_ATTR(version,S_IWUSR | S_IRUGO,version);

int myprobe(struct platform_device *pdev) {
	dev = &pdev->dev;
	root = kobject_create_and_add("mysys005", NULL);
	if (sysfs_create_file(root, &dev_attr_version.attr.attr)) {
		printk(KERN_INFO"Cannot create sysfs file......\n");
		return -1;
	}

	pr_info("myplatformdriver myprobe \n");
	return 0;
}

int myremove(struct platform_device *pdev) {
	pr_info("myplatformdriver myremove \n");
	sysfs_remove_file(root, &dev_attr_version.attr.attr);
	kobject_put(root);
	return 0;
}

struct of_device_id my_of_match_table =
		{ .compatible = "my_platform_device_003", };

struct platform_driver my_platform_driver = { .driver =
		{ .of_match_table = &my_of_match_table, .name = "my-platform-driver",
				.owner = THIS_MODULE, }, .probe = myprobe, .remove = myremove, };

module_platform_driver(my_platform_driver);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Andy");
MODULE_DESCRIPTION("andy one-key driver");
MODULE_ALIAS("one-key");

这里是全部代码