Linux kernel version mismatch - c

Question

I'm trying to create a simple kernel module which makes the keyboard LEDs flashing. It works fine on Linux 3.16 (Ubuntu 14.04) but it doesn't change the LED status on 4.5 (Arch).
I can't figure out what kind of difference causes it, I didn't find anything useful in demsg. Any idea how could I find about this problem?
Code:
#include <linux/module.h>
#include <linux/device.h>
#include <linux/tty.h>
#include <linux/kd.h>
#include <linux/vt.h>
#include <linux/console_struct.h>
#include <linux/vt_kern.h>
#include "device.h"
#include "timer.h"
#define LEDS_ON 0x07
#define LEDS_OFF 0xFF
static int major_number;
static struct class *class;
static struct tty_driver *driver;
static unsigned long led_status = LEDS_OFF;
static void timer_callbak(void)
{
if (led_status == LEDS_OFF) {
led_status = LEDS_ON;
} else {
led_status = LEDS_OFF;
}
driver->ops->ioctl(vc_cons[fg_console].d->port.tty, KDSETLED, led_status);
}
static long device_ioctl(struct file *file, unsigned int command, unsigned long argument)
{
if (command == ON && led_status == LEDS_OFF) {
timer_init(&timer_callbak);
} else if (command == OFF && led_status == LEDS_OFF){
timer_exit();
} else if (command != OFF && command != ON) {
printk(KERN_WARNING "Invalid ioctl() command");
return -1;
}
return 0;
}
static struct file_operations operations = {
.unlocked_ioctl = device_ioctl
};
dev_t create_dev_type(void)
{
return MKDEV(major_number, 0);
}
void create_device(void)
{
major_number = register_chrdev(0, NAME, &operations);
printk("Keyboard leds registered with major_number \"%d\"", major_number);
class = class_create(THIS_MODULE, NAME);
device_create(class, NULL, create_dev_type(), NULL, NAME);
}
void device_init(void)
{
create_device();
driver = vc_cons[fg_console].d->port.tty->driver;
printk("Keyboard leds device Initialized");
}
void device_exit(void)
{
device_destroy(class, create_dev_type());
class_unregister(class);
class_destroy(class);
unregister_chrdev(major_number, NAME);
printk("Keyboard leds device exited");
}
MODULE_LICENSE("GPL");
That's how I'm trying to invoke it:
#include <sys/ioctl.h>
#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include "src/device.h"
int main(void)
{
int fd;
if ((fd = open("/dev/keyboard_leds", O_RDWR|O_NONBLOCK)) < 0) {
perror("Open failed!");
return -1;
}
ioctl(fd, ON);
close(fd);
return 0;
}