#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/proc_fs.h>
#include <linux/keyboard.h>
#include <asm/io.h>

#define PROC_FILE_NAME "kbd_demo"

size_t tcount = 0;
unsigned long int lasttime;
struct notifier_block nb;

ssize_t read_proc(struct file* filp, char *buf, size_t count, loff_t *offp){
	char message[128];
	unsigned long int newtime = jiffies;
	int calls_per_second = (HZ * tcount) / (newtime - lasttime);
	tcount = 0;
	lasttime = newtime;
	sprintf(message, "Calls Per Second: %d\n", calls_per_second);
	strcpy(buf, message);
	return strlen(message);
}

struct file_operations pfo = {
	read : read_proc,
	write: 0
};

int kb_notifier_fn(struct notifier_block *nb, unsigned long action, void* data){
	struct keyboard_notifier_param *kp = (struct keyboard_notifier_param*)data;
	printk("action = %lu Key:  %d  Lights:  %d  Shiftmap:  %x Down:  %d \n", action,  kp->value, kp->ledstate, kp->shift, kp->down);
	if(action == 1 && kp->down)
		tcount++;

	return 0;
}

int init (void) {
	nb.notifier_call = kb_notifier_fn;
	register_keyboard_notifier(&nb);
	proc_create(PROC_FILE_NAME,0,NULL,&pfo);
	return 0;
}

void cleanup(void) {
	unregister_keyboard_notifier(&nb);
	remove_proc_entry(PROC_FILE_NAME,NULL);
}

MODULE_LICENSE("GPL"); 
module_init(init);
module_exit(cleanup);