device_register操作

#include linux/module.h
#include linux/init.h
#include linux/device.h

struct device deviceSY = { 
   .init_name   = "deviceSY", 
};
static struct class *char_dev_class;

static int devicesReg_init(void)
{
 int ret;
 dev_t devno = MKDEV(260,0);
 
 deviceSY.devt = devno; //1.creat "260:0" file in /sys/dev/char/260:0
       //2.creat "deviceSY" file in /dev/deviceSY
    ret = device_register(&deviceSY);//creat "deviceSY" file in /sys/devices/deviceSY  
    if (ret) 
       printk(KERN_NOTICE "Unable to register deviceSY\n"); 

 char_dev_class = class_create(THIS_MODULE,"deviceSY_class");//creat "deviceSY_class" file in /sys/class/deviceSY_class
 if (IS_ERR(char_dev_class))
 {
  printk("Err: failed in creating class.\n");
  return 0;
 }
 
    return ret;
}

static void devicesReg_exit(void)
{
 device_unregister(&deviceSY);
}

MODULE_AUTHOR("SYSMDSY");
MODULE_LICENSE("GPL");

module_init(devicesReg_init);
module_exit(devicesReg_exit);