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

#define BASEPORT 0x378
static unsigned long devid;
int cntr;

static irqreturn_t handler(int irq, void *data)
{
	cntr++;
	printk("parint: >>> Interrupt PARALLEL PORT INT %d HANDLED\n", cntr);
	return IRQ_HANDLED;
}

int xinit_module(void)
{
	int ret;
	ret = request_irq(7, handler,  SA_INTERRUPT   , "parallelport", (void *)&devid);
	if (ret)	{ printk ("parint: error requesting irq 7: returned %d\n", ret); }
	outb_p(0x10, BASEPORT + 2); 

	printk("parint: Generating Interrupt now on all output pins (intr/ACK = pin 10)\n");
	//generate interrupt
	outb_p(0, BASEPORT);
	outb_p(255, BASEPORT);
	outb_p(0, BASEPORT);
	printk("parint: Interrupt generated. You should see the handler-message\n");
	return 0;
}

void xcleanup_module(void)
{
	disable_irq(7);
	free_irq(7, (void *)&devid);
}

module_init(xinit_module);
module_exit(xcleanup_module);
MODULE_LICENSE("GPL");