root/sys/arch/i386/isa/joy.c
/*      $OpenBSD: joy.c,v 1.17 2023/01/30 10:49:05 jsg Exp $    */
/*      $NetBSD: joy.c,v 1.3 1996/05/05 19:46:15 christos Exp $ */

/*-
 * Copyright (c) 1995 Jean-Marc Zucconi
 * All rights reserved.
 *
 * Ported to NetBSD by Matthieu Herrb <matthieu@laas.fr>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer
 *    in this position and unchanged.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/device.h>
#include <sys/errno.h>

#include <machine/pio.h>
#include <machine/cpufunc.h>
#include <machine/joystick.h>
#include <machine/conf.h>

#include <dev/isa/isareg.h>
#include <dev/ic/i8253reg.h>
#include <i386/isa/joyreg.h>

static int      joy_get_tick(void);

struct cfdriver joy_cd = {
        NULL, "joy", DV_DULL
};

int
joyopen(dev_t dev, int flag, int mode, struct proc *p)
{
        int unit = JOYUNIT(dev);
        int i = JOYPART(dev);
        struct joy_softc *sc;

        if (unit >= joy_cd.cd_ndevs)
                return (ENXIO);

        sc = joy_cd.cd_devs[unit];
        if (sc == NULL)
                return (ENXIO);

        if (sc->timeout[i])
                return EBUSY;

        sc->x_off[i] = sc->y_off[i] = 0;
        sc->timeout[i] = JOY_TIMEOUT;
        return 0;
}

int
joyclose(dev_t dev, int flag, int mode, struct proc *p)
{
        int unit = JOYUNIT(dev);
        int i = JOYPART(dev);
        struct joy_softc *sc = joy_cd.cd_devs[unit];

        sc->timeout[i] = 0;
        return 0;
}

int
joyread(dev_t dev, struct uio *uio, int flag)
{
        int unit = JOYUNIT(dev);
        struct joy_softc *sc = joy_cd.cd_devs[unit];
        struct joystick c;
        int port = sc->port;
        int i, t0, t1;
        int state = 0, x = 0, y = 0;
        u_long s;

        s = intr_disable();
        outb(port, 0xff);
        t0 = joy_get_tick();
        t1 = t0;
        i = USEC2TICKS(sc->timeout[JOYPART(dev)]);
        while (t0 - t1 < i) {
                state = inb(port);
                if (JOYPART(dev) == 1)
                        state >>= 2;
                t1 = joy_get_tick();
                if (t1 > t0)
                        t1 -= TIMER_FREQ / hz;
                if (!x && !(state & 0x01))
                        x = t1;
                if (!y && !(state & 0x02))
                        y = t1;
                if (x && y)
                        break;
        }
        intr_restore(s);
        c.x = x ? sc->x_off[JOYPART(dev)] + TICKS2USEC(t0 - x) : 0x80000000;
        c.y = y ? sc->y_off[JOYPART(dev)] + TICKS2USEC(t0 - y) : 0x80000000;
        state >>= 4;
        c.b1 = ~state & 1;
        c.b2 = ~(state >> 1) & 1;
        return uiomove((caddr_t) & c, sizeof(struct joystick), uio);
}

int
joyioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
        int unit = JOYUNIT(dev);
        struct joy_softc *sc = joy_cd.cd_devs[unit];
        int i = JOYPART(dev);
        int x;

        switch (cmd) {
        case JOY_SETTIMEOUT:
                x = *(int *) data;
                if (x < 1 || x > 10000) /* 10ms maximum! */
                        return EINVAL;
                sc->timeout[i] = x;
                break;
        case JOY_GETTIMEOUT:
                *(int *) data = sc->timeout[i];
                break;
        case JOY_SET_X_OFFSET:
                sc->x_off[i] = *(int *) data;
                break;
        case JOY_SET_Y_OFFSET:
                sc->y_off[i] = *(int *) data;
                break;
        case JOY_GET_X_OFFSET:
                *(int *) data = sc->x_off[i];
                break;
        case JOY_GET_Y_OFFSET:
                *(int *) data = sc->y_off[i];
                break;
        default:
                return ENXIO;
        }
        return 0;
}

static int
joy_get_tick(void)
{
        int low, high;

        outb(IO_TIMER1 + TIMER_MODE, TIMER_SEL0);
        low = inb(IO_TIMER1 + TIMER_CNTR0);
        high = inb(IO_TIMER1 + TIMER_CNTR0);

        return (high << 8) | low;
}