lightning.c

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/*
 *  Copyright (c) 1998-2001 Vojtech Pavlik
 */

/*
 * PDPI Lightning 4 gamecard 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 <[email protected]>, or by paper mail:
 * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
 */

#include <asm/io.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/gameport.h>

#define L4_PORT         0x201
#define L4_SELECT_ANALOG    0xa4
#define L4_SELECT_DIGITAL   0xa5
#define L4_SELECT_SECONDARY 0xa6
#define L4_CMD_ID       0x80
#define L4_CMD_GETCAL       0x92
#define L4_CMD_SETCAL       0x93
#define L4_ID           0x04
#define L4_BUSY         0x01
#define L4_TIMEOUT      80  /* 80 us */

MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
MODULE_DESCRIPTION("PDPI Lightning 4 gamecard driver");
MODULE_LICENSE("GPL");

struct l4 {
    struct gameport *gameport;
    unsigned char port;
};

static struct l4 l4_ports[8];

/*
 * l4_wait_ready() waits for the L4 to become ready.
 */

static int l4_wait_ready(void)
{
    unsigned int t = L4_TIMEOUT;

    while ((inb(L4_PORT) & L4_BUSY) && t > 0) t--;
    return -(t <= 0);
}

/*
 * l4_cooked_read() reads data from the Lightning 4.
 */

static int l4_cooked_read(struct gameport *gameport, int *axes, int *buttons)
{
    struct l4 *l4 = gameport->port_data;
    unsigned char status;
    int i, result = -1;

    outb(L4_SELECT_ANALOG, L4_PORT);
    outb(L4_SELECT_DIGITAL + (l4->port >> 2), L4_PORT);

    if (inb(L4_PORT) & L4_BUSY) goto fail;
    outb(l4->port & 3, L4_PORT);

    if (l4_wait_ready()) goto fail;
    status = inb(L4_PORT);

    for (i = 0; i < 4; i++)
        if (status & (1 << i)) {
            if (l4_wait_ready()) goto fail;
            axes[i] = inb(L4_PORT);
            if (axes[i] > 252) axes[i] = -1;
        }

    if (status & 0x10) {
        if (l4_wait_ready()) goto fail;
        *buttons = inb(L4_PORT) & 0x0f;
    }

    result = 0;

fail:   outb(L4_SELECT_ANALOG, L4_PORT);
    return result;
}

static int l4_open(struct gameport *gameport, int mode)
{
    struct l4 *l4 = gameport->port_data;

        if (l4->port != 0 && mode != GAMEPORT_MODE_COOKED)
        return -1;
    outb(L4_SELECT_ANALOG, L4_PORT);
    return 0;
}

/*
 * l4_getcal() reads the L4 with calibration values.
 */

static int l4_getcal(int port, int *cal)
{
    int i, result = -1;

    outb(L4_SELECT_ANALOG, L4_PORT);
    outb(L4_SELECT_DIGITAL + (port >> 2), L4_PORT);
    if (inb(L4_PORT) & L4_BUSY)
        goto out;

    outb(L4_CMD_GETCAL, L4_PORT);
    if (l4_wait_ready())
        goto out;

    if (inb(L4_PORT) != L4_SELECT_DIGITAL + (port >> 2))
        goto out;

    if (l4_wait_ready())
        goto out;
        outb(port & 3, L4_PORT);

    for (i = 0; i < 4; i++) {
        if (l4_wait_ready())
            goto out;
        cal[i] = inb(L4_PORT);
    }

    result = 0;

out:    outb(L4_SELECT_ANALOG, L4_PORT);
    return result;
}

/*
 * l4_setcal() programs the L4 with calibration values.
 */

static int l4_setcal(int port, int *cal)
{
    int i, result = -1;

    outb(L4_SELECT_ANALOG, L4_PORT);
    outb(L4_SELECT_DIGITAL + (port >> 2), L4_PORT);
    if (inb(L4_PORT) & L4_BUSY)
        goto out;

    outb(L4_CMD_SETCAL, L4_PORT);
    if (l4_wait_ready())
        goto out;

    if (inb(L4_PORT) != L4_SELECT_DIGITAL + (port >> 2))
        goto out;

    if (l4_wait_ready())
        goto out;
        outb(port & 3, L4_PORT);

    for (i = 0; i < 4; i++) {
        if (l4_wait_ready())
            goto out;
        outb(cal[i], L4_PORT);
    }

    result = 0;

out:    outb(L4_SELECT_ANALOG, L4_PORT);
    return result;
}

/*
 * l4_calibrate() calibrates the L4 for the attached device, so
 * that the device's resistance fits into the L4's 8-bit range.
 */

static int l4_calibrate(struct gameport *gameport, int *axes, int *max)
{
    int i, t;
    int cal[4];
    struct l4 *l4 = gameport->port_data;

    if (l4_getcal(l4->port, cal))
        return -1;

    for (i = 0; i < 4; i++) {
        t = (max[i] * cal[i]) / 200;
        t = (t < 1) ? 1 : ((t > 255) ? 255 : t);
        axes[i] = (axes[i] < 0) ? -1 : (axes[i] * cal[i]) / t;
        axes[i] = (axes[i] > 252) ? 252 : axes[i];
        cal[i] = t;
    }

    if (l4_setcal(l4->port, cal))
        return -1;

    return 0;
}

static int __init l4_create_ports(int card_no)
{
    struct l4 *l4;
    struct gameport *port;
    int i, idx;

    for (i = 0; i < 4; i++) {

        idx = card_no * 4 + i;
        l4 = &l4_ports[idx];

        if (!(l4->gameport = port = gameport_allocate_port())) {
            printk(KERN_ERR "lightning: Memory allocation failed\n");
            while (--i >= 0) {
                gameport_free_port(l4->gameport);
                l4->gameport = NULL;
            }
            return -ENOMEM;
        }
        l4->port = idx;

        port->port_data = l4;
        port->open = l4_open;
        port->cooked_read = l4_cooked_read;
        port->calibrate = l4_calibrate;

        gameport_set_name(port, "PDPI Lightning 4");
        gameport_set_phys(port, "isa%04x/gameport%d", L4_PORT, idx);

        if (idx == 0)
            port->io = L4_PORT;
    }

    return 0;
}

static int __init l4_add_card(int card_no)
{
    int cal[4] = { 255, 255, 255, 255 };
    int i, rev, result;
    struct l4 *l4;

    outb(L4_SELECT_ANALOG, L4_PORT);
    outb(L4_SELECT_DIGITAL + card_no, L4_PORT);

    if (inb(L4_PORT) & L4_BUSY)
        return -1;
    outb(L4_CMD_ID, L4_PORT);

    if (l4_wait_ready())
        return -1;

    if (inb(L4_PORT) != L4_SELECT_DIGITAL + card_no)
        return -1;

    if (l4_wait_ready())
        return -1;
    if (inb(L4_PORT) != L4_ID)
        return -1;

    if (l4_wait_ready())
        return -1;
    rev = inb(L4_PORT);

    if (!rev)
        return -1;

    result = l4_create_ports(card_no);
    if (result)
        return result;

    printk(KERN_INFO "gameport: PDPI Lightning 4 %s card v%d.%d at %#x\n",
        card_no ? "secondary" : "primary", rev >> 4, rev, L4_PORT);

    for (i = 0; i < 4; i++) {
        l4 = &l4_ports[card_no * 4 + i];

        if (rev > 0x28)     /* on 2.9+ the setcal command works correctly */
            l4_setcal(l4->port, cal);
        gameport_register_port(l4->gameport);
    }

    return 0;
}

static int __init l4_init(void)
{
    int i, cards = 0;

    if (!request_region(L4_PORT, 1, "lightning"))
        return -EBUSY;

    for (i = 0; i < 2; i++)
        if (l4_add_card(i) == 0)
            cards++;

    outb(L4_SELECT_ANALOG, L4_PORT);

    if (!cards) {
        release_region(L4_PORT, 1);
        return -ENODEV;
    }

    return 0;
}

static void __exit l4_exit(void)
{
    int i;
    int cal[4] = { 59, 59, 59, 59 };

    for (i = 0; i < 8; i++)
        if (l4_ports[i].gameport) {
            l4_setcal(l4_ports[i].port, cal);
            gameport_unregister_port(l4_ports[i].gameport);
        }

    outb(L4_SELECT_ANALOG, L4_PORT);
    release_region(L4_PORT, 1);
}

module_init(l4_init);
module_exit(l4_exit);