parkbd.c 4.39 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
/*
 * $Id: parkbd.c,v 1.10 2002/03/13 10:09:20 vojtech Exp $
 *
 *  Copyright (c) 1999-2001 Vojtech Pavlik
 */

/*
 *  Parallel port to Keyboard port adapter driver for Linux
 */

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or 
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 * 
 * Should you need to contact me, the author, you can do so either by
 * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
 */

#include <linux/module.h>
#include <linux/parport.h>
#include <linux/init.h>
#include <linux/serio.h>

MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>");
MODULE_DESCRIPTION("Parallel port to Keyboard port adapter driver");
MODULE_LICENSE("GPL");

MODULE_PARM(parkbd, "1i");
MODULE_PARM(parkbd_mode, "1i");

#define PARKBD_CLOCK	0x01	/* Strobe & Ack */
#define PARKBD_DATA	0x02	/* AutoFd & Busy */

Andrew Morton's avatar
Andrew Morton committed
46
static int parkbd;
47 48
static int parkbd_mode = SERIO_8042;

Andrew Morton's avatar
Andrew Morton committed
49 50 51 52 53
static int parkbd_buffer;
static int parkbd_counter;
static unsigned long parkbd_last;
static int parkbd_writing;
static unsigned long parkbd_start;
54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90

static struct pardevice *parkbd_dev;

static char parkbd_name[] = "PARKBD AT/XT keyboard adapter";
static char parkbd_phys[32];

static int parkbd_readlines(void)
{
	return (parport_read_status(parkbd_dev->port) >> 6) ^ 2;
}

static void parkbd_writelines(int data)
{
	parport_write_control(parkbd_dev->port, (~data & 3) | 0x10);
}

static int parkbd_write(struct serio *port, unsigned char c)
{
	unsigned char p;

	if (!parkbd_mode) return -1;

        p = c ^ (c >> 4);
	p = p ^ (p >> 2);
	p = p ^ (p >> 1);

	parkbd_counter = 0;
	parkbd_writing = 1;
	parkbd_buffer = c | (((int) (~p & 1)) << 8) | 0x600;

	parkbd_writelines(2);

	return 0;
}

static struct serio parkbd_port =
{
91 92 93
	.write	= parkbd_write,
	.name	= parkbd_name,
	.phys	= parkbd_phys,
94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126
};

static void parkbd_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{

	if (parkbd_writing) {

		if (parkbd_counter && ((parkbd_counter == 11) || time_after(jiffies, parkbd_last + HZ/100))) {
			parkbd_counter = 0;
			parkbd_buffer = 0;
			parkbd_writing = 0;
			parkbd_writelines(3);
			return;
		}	

		parkbd_writelines(((parkbd_buffer >> parkbd_counter++) & 1) | 2);

		if (parkbd_counter == 11) {
			parkbd_counter = 0;
			parkbd_buffer = 0;
			parkbd_writing = 0;
			parkbd_writelines(3);
		}

	} else {

		if ((parkbd_counter == parkbd_mode + 10) || time_after(jiffies, parkbd_last + HZ/100)) {
			parkbd_counter = 0;
			parkbd_buffer = 0;
		}	

		parkbd_buffer |= (parkbd_readlines() >> 1) << parkbd_counter++;

127
		if (parkbd_counter == parkbd_mode + 10)
128
			serio_interrupt(&parkbd_port, (parkbd_buffer >> (2 - parkbd_mode)) & 0xff, 0, regs);
129 130 131 132 133 134 135 136 137 138 139 140 141 142
	}

	parkbd_last = jiffies;
}

static int parkbd_getport(void)
{
	struct parport *pp;

	if (parkbd < 0) {
		printk(KERN_ERR "parkbd: no port specified\n");
		return -ENODEV;
	}

Alexander Viro's avatar
Alexander Viro committed
143
	pp = parport_find_number(parkbd);
144 145 146 147 148 149 150

	if (pp == NULL) {
		printk(KERN_ERR "parkbd: no such parport\n");
		return -ENODEV;
	}

	parkbd_dev = parport_register_device(pp, "parkbd", NULL, NULL, parkbd_interrupt, PARPORT_DEV_EXCL, NULL);
Alexander Viro's avatar
Alexander Viro committed
151
	parport_put_port(pp);
152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191

	if (!parkbd_dev)
		return -ENODEV;

	if (parport_claim(parkbd_dev)) {
		parport_unregister_device(parkbd_dev);
		return -EBUSY;
	}

	parkbd_start = jiffies;

	return 0;
}


int __init parkbd_init(void)
{
	if (parkbd_getport()) return -1;
	parkbd_writelines(3);
	parkbd_port.type = parkbd_mode;

	sprintf(parkbd_phys, "%s/serio0", parkbd_dev->port->name);

	serio_register_port(&parkbd_port);

	printk(KERN_INFO "serio: PARKBD %s adapter on %s\n",
                        parkbd_mode ? "AT" : "XT", parkbd_dev->port->name);

	return 0;
}

void __exit parkbd_exit(void)
{
	parport_release(parkbd_dev);
	serio_unregister_port(&parkbd_port);
	parport_unregister_device(parkbd_dev);
}

module_init(parkbd_init);
module_exit(parkbd_exit);