#include <board.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/regulator/consumer.h>
#include <sound/soc.h>
#include <sound/jack.h>


static
 
  char mybuf[100]="123";
static ssize_t show_my_device(struct device *dev,
                  struct device_attribute *attr, char *buf)        //cat命令時,將會呼叫該函式
{
    return sprintf(buf, "%s\n", mybuf);
}

static ssize_t set_my_device(struct device *dev,
                 struct device_attribute *attr,
                 
 
const char *buf, size_t len)        //echo命令時,將會呼叫該函式
{
    sprintf(mybuf, "%s", buf);
    return len;
}
static DEVICE_ATTR(my_device_test, S_IWUSR|S_IRUSR, show_my_device, set_my_device);
                //定義一個名字為my_device_test的裝置屬性檔案
                
struct file_operations mytest_ops={
         .owner  
 
= THIS_MODULE,
};

static int major;
static struct class *cls;
static int mytest_init(void)
{
         struct device *mydev;   
         major=register_chrdev(0,"mytest", &mytest_ops);
         cls=class_create(THIS_MODULE, "mytest_class");
         mydev = device_create(cls, 0, MKDEV(major,0),NULL,"mytest_device");    //建立mytest_device裝置    
    
    if(sysfs_create_file(&(mydev->kobj), &dev_attr_my_device_test.attr)){    //在mytest_device裝置目錄下建立一個my_device_test屬性檔案
            return -1;}
            
         return 0;
}

static void mytest_exit(void)
{
         device_destroy(cls, MKDEV(major,0));
         class_destroy(cls);
         unregister_chrdev(major, "mytest");
}

module_init(mytest_init);
module_exit(mytest_exit);
MODULE_LICENSE("GPL");