/* beep speaker */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <asm/string.h>
#include <asm/io.h>

#define SPEAKER_PORT 0x61
#define PORT 0xFC
#define HZ_MN1 0xff
#define HZ_MN2 0x42
#define __bad_udelay()	"wrong"

static void kd_nosound(unsigned long ignored)
{
	   /* acesssando port space */
           /* outb - saida em 8-bit */
	   /* inb_p - entrada em 8-bit */
           outb(inb_p(SPEAKER_PORT) & PORT, SPEAKER_PORT);
           return;
}

static void kd_mksound(unsigned int hz, unsigned int ticks)
{
 static struct timer_list sound_timer = { 
	function:	kd_nosound
 };

           unsigned int count = 0;
	   unsigned long flags;

           if (hz > 20 && hz < 32767)
                   count = 1193180 / hz;

	   save_flags(flags);	
	   cli();
	   
           del_timer(&sound_timer);
           if (count) {
                   outb_p(inb_p(SPEAKER_PORT) | 3, SPEAKER_PORT);
                   outb_p(0xB6, 0x43);
		   /* selecionar HZ desejado */
                   outb_p(count & HZ_MN1, HZ_MN2);
                   outb((count >> 8) & HZ_MN1, HZ_MN2);

                   if (ticks) {
                           sound_timer.expires = jiffies+ticks;
                           add_timer(&sound_timer);
                   }
           } else
                   kd_nosound(0);
	   restore_flags(flags);
           return;
}

void cleanup_module(void)
{
printk(KERN_INFO "Até! \n");
}

int init_module(void)
{

     kd_mksound(494,120);
     mdelay(200);
     kd_mksound(1,140);
     mdelay(100);
     kd_mksound(330,120);
     mdelay(200);
     kd_mksound(1,120);
     mdelay(100);
     kd_mksound(415,120);
     mdelay(200);
     kd_mksound(1,120);
     mdelay(100);
     kd_mksound(494,120);
     mdelay(200);
     kd_mksound(1,120);
     mdelay(100);

     kd_mksound(0,0);
     return 0;
}

MODULE_AUTHOR("Guilherme Polo");
MODULE_LICENSE("GPL");
EXPORT_NO_SYMBOLS;