#include <linux/ioport.h>
#include <asm/io.h>
#include <linux/errno.h>
#include <stdio.h>
#include <unistd.h>

static unsigned char PortData = 0;
static unsigned char PortStatus = 0;
static unsigned char PortCtl = 0;

#define BASE 	0x378
#define DATA	(unsigned int)(BASE)	/* Centronics data port		*/
#define STAT	(BASE+1)		/* Centronics status port	*/
#define CTRL	(BASE+2)		/* Centronics control port	*/


/* ----- local functions ----------------------------------------------	*/


static void bit_mcselec_setscl(int data, int state)
{
	if (state) {
		PortCtl |= 0x08;
	} else {
		PortCtl &= 0xf7;
	}
	outb(PortCtl, CTRL);
}

static void bit_mcselec_setsda(int data, int state)
{
	if (state) {
		PortData &= 0x7f;
	} else {
		PortData |= 0x80;
	}
	outb(PortData, DATA);
} 

static int bit_mcselec_getscl(int data)
{
	return (inb(STAT) & 0x08);
}

static int bit_mcselec_getsda(int data)
{
	return (inb(STAT) & 0x80);
}

main () {
	char tmp[3];
	if (ioperm(BASE, 3, 1)) {
		perror("ioperm");
		exit(1);
	}
	printf("Will test SDA\n");
	printf("SDA High\n");
	bit_mcselec_setsda(BASE, 1);
	sleep(1);
	printf("Reading SDA: %d\n", bit_mcselec_getsda(BASE));
	printf("Press ENTER to continue");
	fgets(tmp, 2, stdin);
	printf("SDA Low\n");
	bit_mcselec_setsda(BASE, 0);
	sleep(1);
	printf("Reading SDA: %d\n", bit_mcselec_getsda(BASE));
	printf("Press ENTER to continue");
	fgets(tmp, 2, stdin);
	printf("Will test SCL\n");
	printf("SCL High\n");
	bit_mcselec_setscl(BASE, 1);
	sleep(1);
	printf("Reading SCL: %d\n", bit_mcselec_getscl(BASE));
	printf("Press ENTER to continue");
	fgets(tmp, 2, stdin);
	printf("SCL Low\n");
	bit_mcselec_setscl(BASE, 0);
	sleep(1);
	printf("Reading SCL: %d\n", bit_mcselec_getscl(BASE));
	printf("Press ENTER to continue");
	fgets(tmp, 2, stdin);
	printf("Exit\n");
	return 0;
}