/*      $OpenBSD: lpt.c,v 1.17 2025/06/25 20:28:09 miod Exp $ */
/*      $NetBSD: lpt.c,v 1.42 1996/10/21 22:41:14 thorpej Exp $ */

/*
 * Copyright (c) 1993, 1994 Charles Hannum.
 * Copyright (c) 1990 William F. Jolitz, TeleMuse
 * All rights reserved.
 *
 * 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.
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This software is a component of "386BSD" developed by 
 *      William F. Jolitz, TeleMuse.
 * 4. Neither the name of the developer nor the name "386BSD"
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS A COMPONENT OF 386BSD DEVELOPED BY WILLIAM F. JOLITZ 
 * AND IS INTENDED FOR RESEARCH AND EDUCATIONAL PURPOSES ONLY. THIS 
 * SOFTWARE SHOULD NOT BE CONSIDERED TO BE A COMMERCIAL PRODUCT. 
 * THE DEVELOPER URGES THAT USERS WHO REQUIRE A COMMERCIAL PRODUCT 
 * NOT MAKE USE OF THIS WORK.
 *
 * FOR USERS WHO WISH TO UNDERSTAND THE 386BSD SYSTEM DEVELOPED
 * BY WILLIAM F. JOLITZ, WE RECOMMEND THE USER STUDY WRITTEN 
 * REFERENCES SUCH AS THE  "PORTING UNIX TO THE 386" SERIES 
 * (BEGINNING JANUARY 1991 "DR. DOBBS JOURNAL", USA AND BEGINNING 
 * JUNE 1991 "UNIX MAGAZIN", GERMANY) BY WILLIAM F. JOLITZ AND 
 * LYNNE GREER JOLITZ, AS WELL AS OTHER BOOKS ON UNIX AND THE 
 * ON-LINE 386BSD USER MANUAL BEFORE USE. A BOOK DISCUSSING THE INTERNALS 
 * OF 386BSD ENTITLED "386BSD FROM THE INSIDE OUT" WILL BE AVAILABLE LATE 1992.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPER ``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 DEVELOPER 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.
 */

/*
 * Device Driver for AT parallel printer port
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/uio.h>
#include <sys/device.h>
#include <sys/conf.h>
#include <sys/syslog.h>

#include <machine/bus.h>
#include <machine/intr.h>

#include <dev/ic/lptreg.h>
#include <dev/ic/lptvar.h>

#include "lpt.h"

#define TIMEOUT         16000   /* wait up to 16 seconds for a ready */
#define STEP            250     /* 1/4 seconds */

#define LPTPRI          (PZERO+8)
#define LPT_BSIZE       1024

#if !defined(DEBUG) || !defined(notdef)
#define LPRINTF(a)
#else
#define LPRINTF(a)      if (lptdebug) printf a
int lptdebug = 1;
#endif

/* XXX does not belong here */
cdev_decl(lpt);

struct cfdriver lpt_cd = {
        NULL, "lpt", DV_TTY
};

#define LPTUNIT(s)      (minor(s) & 0x1f)
#define LPTFLAGS(s)     (minor(s) & 0xe0)

#define LPS_INVERT      (LPS_SELECT|LPS_NERR|LPS_NBSY|LPS_NACK)
#define LPS_MASK        (LPS_SELECT|LPS_NERR|LPS_NBSY|LPS_NACK|LPS_NOPAPER)
#define NOT_READY() \
    ((bus_space_read_1(sc->sc_iot, sc->sc_ioh, lpt_status) ^ LPS_INVERT) & LPS_MASK)
#define NOT_READY_ERR() \
    lpt_not_ready(bus_space_read_1(sc->sc_iot, sc->sc_ioh, lpt_status), sc)

int     lpt_not_ready(u_int8_t, struct lpt_softc *);
void    lptwakeup(void *arg);
int     lptpushbytes(struct lpt_softc *);

/*
 * Internal routine to lptprobe to do port tests of one byte value.
 */
int
lpt_port_test(bus_space_tag_t iot, bus_space_handle_t ioh, bus_addr_t base,
    bus_size_t off, u_int8_t data, u_int8_t mask)
{
        int timeout;
        u_int8_t temp;

        data &= mask;
        bus_space_write_1(iot, ioh, off, data);
        timeout = 1000;
        do {
                delay(10);
                temp = bus_space_read_1(iot, ioh, off) & mask;
        } while (temp != data && --timeout);
        LPRINTF(("lpt: port=0x%x out=0x%x in=0x%x timeout=%d\n", base + off,
            data, temp, timeout));
        return (temp == data);
}

void
lpt_attach_common(struct lpt_softc *sc)
{
        printf("\n");

        bus_space_write_1(sc->sc_iot, sc->sc_ioh, lpt_control, LPC_NINIT);

        timeout_set(&sc->sc_wakeup_tmo, lptwakeup, sc);
}

/*
 * Reset the printer, then wait until it's selected and not busy.
 */
int
lptopen(dev_t dev, int flag, int mode, struct proc *p)
{
        int unit = LPTUNIT(dev);
        u_int8_t flags = LPTFLAGS(dev);
        struct lpt_softc *sc;
        u_int8_t control;
        int error;
        int spin;

        if (unit >= lpt_cd.cd_ndevs)
                return ENXIO;
        sc = lpt_cd.cd_devs[unit];
        if (!sc)
                return ENXIO;

        sc->sc_flags = (sc->sc_flags & LPT_POLLED) | flags;
        if ((sc->sc_flags & (LPT_POLLED|LPT_NOINTR)) == LPT_POLLED)
                return ENXIO;

#ifdef DIAGNOSTIC
        if (sc->sc_state)
                printf("%s: stat=0x%x not zero\n", sc->sc_dev.dv_xname,
                    sc->sc_state);
#endif

        if (sc->sc_state)
                return EBUSY;

        sc->sc_state = LPT_INIT;
        LPRINTF(("%s: open: flags=0x%x\n", sc->sc_dev.dv_xname, flags));

        if ((flags & LPT_NOPRIME) == 0) {
                /* assert INIT for 100 usec to start up printer */
                bus_space_write_1(sc->sc_iot, sc->sc_ioh, lpt_control, LPC_SELECT);
                delay(100);
        }

        control = LPC_SELECT | LPC_NINIT;
        bus_space_write_1(sc->sc_iot, sc->sc_ioh, lpt_control, control);

        /* wait till ready (printer running diagnostics) */
        for (spin = 0; NOT_READY_ERR(); spin += STEP) {
                if (spin >= TIMEOUT) {
                        sc->sc_state = 0;
                        return EBUSY;
                }

                /* wait 1/4 second, give up if we get a signal */
                error = tsleep_nsec(sc, LPTPRI | PCATCH, "lptopen",
                    MSEC_TO_NSEC(STEP));
                if (sc->sc_state == 0)
                        return (EIO);
                if (error != EWOULDBLOCK) {
                        sc->sc_state = 0;
                        return error;
                }
        }

        if ((flags & LPT_NOINTR) == 0)
                control |= LPC_IENABLE;
        if (flags & LPT_AUTOLF)
                control |= LPC_AUTOLF;
        sc->sc_control = control;
        bus_space_write_1(sc->sc_iot, sc->sc_ioh, lpt_control, control);

        sc->sc_inbuf = malloc(LPT_BSIZE, M_DEVBUF, M_WAITOK);
        sc->sc_count = 0;
        sc->sc_state = LPT_OPEN;

        if ((sc->sc_flags & LPT_NOINTR) == 0)
                lptwakeup(sc);

        LPRINTF(("%s: opened\n", sc->sc_dev.dv_xname));
        return 0;
}

int
lpt_not_ready(u_int8_t status, struct lpt_softc *sc)
{
        u_int8_t new;

        status = (status ^ LPS_INVERT) & LPS_MASK;
        new = status & ~sc->sc_laststatus;
        sc->sc_laststatus = status;

        if (new & LPS_SELECT)
                log(LOG_NOTICE, "%s: offline\n", sc->sc_dev.dv_xname);
        else if (new & LPS_NOPAPER)
                log(LOG_NOTICE, "%s: out of paper\n", sc->sc_dev.dv_xname);
        else if (new & LPS_NERR)
                log(LOG_NOTICE, "%s: output error\n", sc->sc_dev.dv_xname);

        return status;
}

void
lptwakeup(void *arg)
{
        struct lpt_softc *sc = arg;
        int s;

        s = spltty();
        lptintr(sc);
        splx(s);

        if (sc->sc_state != 0)
                timeout_add_msec(&sc->sc_wakeup_tmo, STEP);
}

/*
 * Close the device, and free the local line buffer.
 */
int
lptclose(dev_t dev, int flag, int mode, struct proc *p)
{
        int unit = LPTUNIT(dev);
        struct lpt_softc *sc = lpt_cd.cd_devs[unit];
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        if (sc->sc_count)
                (void) lptpushbytes(sc);

        if ((sc->sc_flags & LPT_NOINTR) == 0)
                timeout_del(&sc->sc_wakeup_tmo);

        bus_space_write_1(iot, ioh, lpt_control, LPC_NINIT);
        sc->sc_state = 0;
        bus_space_write_1(iot, ioh, lpt_control, LPC_NINIT);
        free(sc->sc_inbuf, M_DEVBUF, LPT_BSIZE);

        LPRINTF(("%s: closed\n", sc->sc_dev.dv_xname));
        return 0;
}

int
lptpushbytes(struct lpt_softc *sc)
{
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;
        int error;

        if (sc->sc_flags & LPT_NOINTR) {
                int msecs, spin;
                u_int8_t control = sc->sc_control;

                while (sc->sc_count > 0) {
                        spin = 0;
                        if (sc->sc_state == 0)
                                return (EIO);
                        while (NOT_READY()) {
                                if (++spin < sc->sc_spinmax)
                                        continue;
                                msecs = 0;
                                /* adapt busy-wait algorithm */
                                sc->sc_spinmax++;
                                while (NOT_READY_ERR()) {
                                        /* exponential backoff */
                                        msecs = msecs + msecs + 10;
                                        if (msecs > TIMEOUT)
                                                msecs = TIMEOUT;
                                        error = tsleep_nsec(sc,
                                            LPTPRI | PCATCH, "lptpsh",
                                            MSEC_TO_NSEC(msecs));
                                        if (sc->sc_state == 0)
                                                error = EIO;
                                        if (error != EWOULDBLOCK)
                                                return error;
                                }
                                break;
                        }

                        bus_space_write_1(iot, ioh, lpt_data, *sc->sc_cp++);
                        bus_space_write_1(iot, ioh, lpt_control,
                            control | LPC_STROBE);
                        sc->sc_count--;
                        bus_space_write_1(iot, ioh, lpt_control, control);

                        /* adapt busy-wait algorithm */
                        if (spin*2 + 16 < sc->sc_spinmax)
                                sc->sc_spinmax--;
                }
        } else {
                int s;

                while (sc->sc_count > 0) {
                        /* if the printer is ready for a char, give it one */
                        if ((sc->sc_state & LPT_OBUSY) == 0) {
                                LPRINTF(("%s: write %d\n", sc->sc_dev.dv_xname,
                                    sc->sc_count));
                                s = spltty();
                                (void) lptintr(sc);
                                splx(s);
                        }
                        if (sc->sc_state == 0)
                                return (EIO);
                        error = tsleep_nsec(sc, LPTPRI | PCATCH,
                            "lptwrite2", INFSLP);
                        if (sc->sc_state == 0)
                                error = EIO;
                        if (error)
                                return error;
                }
        }
        return 0;
}

/* 
 * Copy a line from user space to a local buffer, then call putc to get the
 * chars moved to the output queue.
 */
int
lptwrite(dev_t dev, struct uio *uio, int flags)
{
        struct lpt_softc *sc = lpt_cd.cd_devs[LPTUNIT(dev)];
        size_t n;
        int error = 0;

        while ((n = ulmin(LPT_BSIZE, uio->uio_resid)) != 0) {
                sc->sc_cp = sc->sc_inbuf;
                error = uiomove(sc->sc_cp, n, uio);
                if (error != 0)
                        return error;
                sc->sc_count = n;
                error = lptpushbytes(sc);
                if (error) {
                        /*
                         * Return accurate residual if interrupted or timed
                         * out.
                         */
                        uio->uio_resid += sc->sc_count;
                        sc->sc_count = 0;
                        return error;
                }
        }
        return 0;
}

/*
 * Handle printer interrupts which occur when the printer is ready to accept
 * another char.
 */
int
lptintr(void *arg)
{
        struct lpt_softc *sc = arg;
        bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh = sc->sc_ioh;

        if (((sc->sc_state & LPT_OPEN) == 0 && sc->sc_count == 0) ||
            (sc->sc_flags & LPT_NOINTR))
                return 0;

        /* is printer online and ready for output */
        if (NOT_READY() && NOT_READY_ERR())
                return -1;

        if (sc->sc_count) {
                u_int8_t control = sc->sc_control;
                /* send char */
                bus_space_write_1(iot, ioh, lpt_data, *sc->sc_cp++);
                delay (50);
                bus_space_write_1(iot, ioh, lpt_control, control | LPC_STROBE);
                sc->sc_count--;
                bus_space_write_1(iot, ioh, lpt_control, control);
                sc->sc_state |= LPT_OBUSY;
        } else
                sc->sc_state &= ~LPT_OBUSY;

        if (sc->sc_count == 0) {
                /* none, wake up the top half to get more */
                wakeup((caddr_t)sc);
        }

        return 1;
}

int
lpt_activate(struct device *self, int act)
{
        struct lpt_softc *sc = (struct lpt_softc *)self;

        switch (act) {
        case DVACT_SUSPEND:
                timeout_del(&sc->sc_wakeup_tmo);
                break;
        case DVACT_RESUME:
                bus_space_write_1(sc->sc_iot, sc->sc_ioh, lpt_control, LPC_NINIT);

                if (sc->sc_state) {
                        int spin;

                        if ((sc->sc_flags & LPT_NOPRIME) == 0) {
                                /* assert INIT for 100 usec to start up printer */
                                bus_space_write_1(sc->sc_iot, sc->sc_ioh,
                                    lpt_control, LPC_SELECT);
                                delay(100);
                        }
                        
                        bus_space_write_1(sc->sc_iot, sc->sc_ioh, lpt_control,
                            LPC_SELECT | LPC_NINIT);

                        /* wait till ready (printer running diagnostics) */
                        for (spin = 0; NOT_READY_ERR(); spin += STEP) {
                                if (spin >= TIMEOUT) {
                                        sc->sc_state = 0;
                                        goto fail;
                                }

                                /* wait 1/4 second, give up if we get a signal */
                                delay(STEP * 1000);
                        }

                        bus_space_write_1(sc->sc_iot, sc->sc_ioh,
                            lpt_control, sc->sc_control);
                        wakeup(sc);
                }
fail:
                break;
        }
 
        return (0);
}