#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/cdev.h>
#include <linux/fs.h>
#include <linux/wait.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/device.h> 

#include "pub.h"

MODULE_LICENSE("GPL");
MODULE_AUTHOR("liuchao");


extern struct bus_type my_bus;

void my_dev_release(struct device *dev)
{
    printk("%s-%s\n", __FILE__, __func__);
}


static struct device my_dev = {
    .init_name = "my_dev",
    .bus = &my_bus,
    .release = my_dev_release,
};


unsigned long id = 0;
ssize_t my_dev_id_show(struct device *dev, struct device_attribute *attr,
                char *buf)
{
    return sprintf(buf, "%d\n", id);
}

ssize_t my_dev_id_store(struct device *dev, struct device_attribute *attr,
                const char *buf, size_t count)
{
    kstrtoul(buf, 10, &id);
    return count;
}


DEVICE_ATTR(my_dev_id, S_IRUSR|S_IWUSR, my_dev_id_show, my_dev_id_store);

static __init int my_dev_init(void)
{
    printk("my_dev init\n");
    device_register(&my_dev);
    device_create_file(&my_dev, &dev_attr_my_dev_id);
    return 0;
}
module_init(my_dev_init);


static __exit void my_dev_exit(void)
{
    printk("xdev exit\n");
    device_remove_file(&my_dev, &dev_attr_my_dev_id);
    device_unregister(&my_dev);
}
module_exit(my_dev_exit);