/*      $NetBSD: dl.c,v 1.49 2014/07/25 08:10:38 dholland Exp $ */

/*-
 * Copyright (c) 1996, 1997 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jason R. Thorpe.
 *
 * 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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.
 */

/*
 * Copyright (c) 1997  Ben Harris.  All rights reserved.
 * Copyright (c) 1982, 1986, 1990, 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ralph Campbell and Rick Macklem.
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

/*
 * Copyright (c) 1996  Ken C. Wellsch.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Ralph Campbell and Rick Macklem.
 *
 * 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 product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

/*
 * dl.c -- Device driver for the DL11 and DLV11 serial cards.
 *
 * OS-interface code derived from the dz and dca (hp300) drivers.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: dl.c,v 1.49 2014/07/25 08:10:38 dholland Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/ioctl.h>
#include <sys/tty.h>
#include <sys/proc.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/uio.h>
#include <sys/kernel.h>
#include <sys/syslog.h>
#include <sys/device.h>
#include <sys/kauth.h>

#include <sys/bus.h>

#include <dev/qbus/ubavar.h>

#include <dev/qbus/dlreg.h>

#include "ioconf.h"

struct dl_softc {
        device_t        sc_dev;
        struct evcnt    sc_rintrcnt;
        struct evcnt    sc_tintrcnt;
        bus_space_tag_t sc_iot;
        bus_space_handle_t sc_ioh;
        struct tty      *sc_tty;
};

static  int     dl_match (device_t, cfdata_t, void *);
static  void    dl_attach (device_t, device_t, void *);
static  void    dlrint (void *);
static  void    dlxint (void *);
static  void    dlstart (struct tty *);
static  int     dlparam (struct tty *, struct termios *);
static  void    dlbrk (struct dl_softc *, int);

CFATTACH_DECL_NEW(dl, sizeof(struct dl_softc),
    dl_match, dl_attach, NULL, NULL);

dev_type_open(dlopen);
dev_type_close(dlclose);
dev_type_read(dlread);
dev_type_write(dlwrite);
dev_type_ioctl(dlioctl);
dev_type_stop(dlstop);
dev_type_tty(dltty);
dev_type_poll(dlpoll);

const struct cdevsw dl_cdevsw = {
        .d_open = dlopen,
        .d_close = dlclose,
        .d_read = dlread,
        .d_write = dlwrite,
        .d_ioctl = dlioctl,
        .d_stop = dlstop,
        .d_tty = dltty,
        .d_poll = dlpoll,
        .d_mmap = nommap,
        .d_kqfilter = ttykqfilter,
        .d_discard = nodiscard,
        .d_flag = D_TTY
};

#define DL_READ_WORD(reg) \
        bus_space_read_2(sc->sc_iot, sc->sc_ioh, reg)
#define DL_WRITE_WORD(reg, val) \
        bus_space_write_2(sc->sc_iot, sc->sc_ioh, reg, val)
#define DL_WRITE_BYTE(reg, val) \
        bus_space_write_1(sc->sc_iot, sc->sc_ioh, reg, val)

/* Autoconfig handles: setup the controller to interrupt, */
/* then complete the housecleaning for full operation */

static int
dl_match (device_t parent, cfdata_t cf, void *aux)
{
        struct uba_attach_args *ua = aux;

#ifdef DL_DEBUG
        printf("Probing for dl at %lo ... ", (long)ua->ua_iaddr);
#endif

        bus_space_write_2(ua->ua_iot, ua->ua_ioh, DL_UBA_XCSR, DL_XCSR_TXIE);
        if (bus_space_read_2(ua->ua_iot, ua->ua_ioh, DL_UBA_XCSR) !=
            (DL_XCSR_TXIE | DL_XCSR_TX_READY)) {
#ifdef DL_DEBUG
                printf("failed (step 1; XCSR = %.4b)\n",
                    bus_space_read_2(ua->ua_iot, ua->ua_ioh, DL_UBA_XCSR),
                    DL_XCSR_BITS);
#endif
                return 0;
        }

        /*
         * We have to force an interrupt so the uba driver can work
         * out where we are.  Unfortunately, the only way to make a
         * DL11 interrupt is to get it to send or receive a
         * character.  We'll send a NUL and hope it doesn't hurt
         * anything.
         */

        bus_space_write_1(ua->ua_iot, ua->ua_ioh, DL_UBA_XBUFL, '\0');
#if 0 /* This test seems to fail 2/3 of the time :-( */
        if (dladdr->dl_xcsr != (DL_XCSR_TXIE)) {
#ifdef DL_DEBUG
                printf("failed (step 2; XCSR = %.4b)\n", dladdr->dl_xcsr,
                    DL_XCSR_BITS);
#endif
                return 0;
        }
#endif
        DELAY(100000); /* delay 1/10 s for character to transmit */
        if (bus_space_read_2(ua->ua_iot, ua->ua_ioh, DL_UBA_XCSR) !=
            (DL_XCSR_TXIE | DL_XCSR_TX_READY)) {
#ifdef DL_DEBUG
                printf("failed (step 3; XCSR = %.4b)\n",
                    bus_space_read_2(ua->ua_iot, ua->ua_ioh, DL_UBA_XCSR),
                    DL_XCSR_BITS);
#endif
                return 0;
        }


        /* What else do I need to do? */

        return 1;

}

static void
dl_attach (device_t parent, device_t self, void *aux)
{
        struct dl_softc *sc = device_private(self);
        struct uba_attach_args *ua = aux;

        sc->sc_dev = self;
        sc->sc_iot = ua->ua_iot;
        sc->sc_ioh = ua->ua_ioh;

        /* Tidy up the device */

        DL_WRITE_WORD(DL_UBA_RCSR, DL_RCSR_RXIE);
        DL_WRITE_WORD(DL_UBA_XCSR, DL_XCSR_TXIE);

        /* Initialize our softc structure. Should be done in open? */

        sc->sc_tty = tty_alloc();
        tty_attach(sc->sc_tty);

        /* Now register the TX & RX interrupt handlers */
        uba_intr_establish(ua->ua_icookie, ua->ua_cvec,
                dlxint, sc, &sc->sc_tintrcnt);
        uba_intr_establish(ua->ua_icookie, ua->ua_cvec - 4,
                dlrint, sc, &sc->sc_rintrcnt);
        evcnt_attach_dynamic(&sc->sc_rintrcnt, EVCNT_TYPE_INTR, ua->ua_evcnt,
                device_xname(sc->sc_dev), "rintr");
        evcnt_attach_dynamic(&sc->sc_tintrcnt, EVCNT_TYPE_INTR, ua->ua_evcnt,
                device_xname(sc->sc_dev), "tintr");

        printf("\n");
}

/* Receiver Interrupt Handler */

static void
dlrint(void *arg)
{
        struct dl_softc *sc = arg;

        if (DL_READ_WORD(DL_UBA_RCSR) & DL_RCSR_RX_DONE) {
                struct tty *tp = sc->sc_tty;
                unsigned c;
                int cc;

                c = DL_READ_WORD(DL_UBA_RBUF);
                cc = c & 0xFF;

                if (!(tp->t_state & TS_ISOPEN)) {
                        cv_broadcast(&tp->t_rawcv);
                        return;
                }

                if (c & DL_RBUF_OVERRUN_ERR) {
                        /*
                         * XXX: This should really be logged somwhere
                         * else where we can afford the time.
                         */
                        log(LOG_WARNING, "%s: rx overrun\n",
                            device_xname(sc->sc_dev));
                }
                if (c & DL_RBUF_FRAMING_ERR)
                        cc |= TTY_FE;
                if (c & DL_RBUF_PARITY_ERR)
                        cc |= TTY_PE;

                (*tp->t_linesw->l_rint)(cc, tp);
#if defined(DIAGNOSTIC)
        } else {
                log(LOG_WARNING, "%s: stray rx interrupt\n",
                    device_xname(sc->sc_dev));
#endif
        }
}

/* Transmitter Interrupt Handler */

static void
dlxint(void *arg)
{
        struct dl_softc *sc = arg;
        struct tty *tp = sc->sc_tty;

        tp->t_state &= ~(TS_BUSY | TS_FLUSH);
        (*tp->t_linesw->l_start)(tp);

        return;
}

int
dlopen(dev_t dev, int flag, int mode, struct lwp *l)
{
        struct tty *tp;
        struct dl_softc *sc;
        int unit;

        unit = minor(dev);

        sc = device_lookup_private(&dl_cd, unit);
        if (!sc)
                return ENXIO;

        tp = sc->sc_tty;
        if (tp == NULL)
                return ENODEV;
        tp->t_oproc = dlstart;
        tp->t_param = dlparam;
        tp->t_dev = dev;

        if (kauth_authorize_device_tty(l->l_cred, KAUTH_DEVICE_TTY_OPEN, tp))
                return (EBUSY);

        if (!(tp->t_state & TS_ISOPEN)) {
                ttychars(tp);
                tp->t_iflag = TTYDEF_IFLAG;
                tp->t_oflag = TTYDEF_OFLAG;
                /* No modem control, so set CLOCAL. */
                tp->t_cflag = TTYDEF_CFLAG | CLOCAL;
                tp->t_lflag = TTYDEF_LFLAG;
                tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;

                dlparam(tp, &tp->t_termios);
                ttsetwater(tp);

        }

        return ((*tp->t_linesw->l_open)(dev, tp));
}

/*ARGSUSED*/
int
dlclose(dev_t dev, int flag, int mode, struct lwp *l)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(dev));
        struct tty *tp = sc->sc_tty;

        (*tp->t_linesw->l_close)(tp, flag);

        /* Make sure a BREAK state is not left enabled. */
        dlbrk(sc, 0);

        return (ttyclose(tp));
}

int
dlread(dev_t dev, struct uio *uio, int flag)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(dev));
        struct tty *tp = sc->sc_tty;

        return ((*tp->t_linesw->l_read)(tp, uio, flag));
}

int
dlwrite(dev_t dev, struct uio *uio, int flag)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(dev));
        struct tty *tp = sc->sc_tty;

        return ((*tp->t_linesw->l_write)(tp, uio, flag));
}

int
dlpoll(dev_t dev, int events, struct lwp *l)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(dev));
        struct tty *tp = sc->sc_tty;

        return ((*tp->t_linesw->l_poll)(tp, events, l));
}

int
dlioctl(dev_t dev, unsigned long cmd, void *data, int flag, struct lwp *l)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(dev));
        struct tty *tp = sc->sc_tty;
        int error;


        error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, l);
        if (error != EPASSTHROUGH)
                return (error);

        error = ttioctl(tp, cmd, data, flag, l);
        if (error != EPASSTHROUGH)
                return (error);

        switch (cmd) {

        case TIOCSBRK:
                dlbrk(sc, 1);
                break;

        case TIOCCBRK:
                dlbrk(sc, 0);
                break;

        case TIOCMGET:
                /* No modem control, assume they're all low. */
                *(int *)data = 0;
                break;

        default:
                return (EPASSTHROUGH);
        }
        return (0);
}

struct tty *
dltty(dev_t dev)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(dev));

        return sc->sc_tty;
}

void
dlstop(struct tty *tp, int flag)
{
        int s = spltty();

        if ((tp->t_state & (TS_BUSY|TS_TTSTOP)) == TS_BUSY)
                tp->t_state |= TS_FLUSH;
        splx(s);
}

static void
dlstart(struct tty *tp)
{
        struct dl_softc *sc = device_lookup_private(&dl_cd, minor(tp->t_dev));
        int s = spltty();

        if (tp->t_state & (TS_TIMEOUT|TS_BUSY|TS_TTSTOP))
                goto out;
        if (!ttypull(tp))
                goto out;
        if (DL_READ_WORD(DL_UBA_XCSR) & DL_XCSR_TX_READY) {
                tp->t_state |= TS_BUSY;
                DL_WRITE_BYTE(DL_UBA_XBUFL, getc(&tp->t_outq));
        }
out:
        splx(s);
        return;
}

/*ARGSUSED*/
static int
dlparam(struct tty *tp, struct termios *t)
{
        /*
         * All this kind of stuff (speed, character format, whatever)
         * is set by jumpers on the card.  Changing it is thus rather
         * tricky for a mere device driver.
         */
        return 0;
}

static void
dlbrk(struct dl_softc *sc, int state)
{
        int s = spltty();

        if (state) {
                DL_WRITE_WORD(DL_UBA_XCSR, DL_READ_WORD(DL_UBA_XCSR) |
                    DL_XCSR_TX_BREAK);
        } else {
                DL_WRITE_WORD(DL_UBA_XCSR, DL_READ_WORD(DL_UBA_XCSR) &
                    ~DL_XCSR_TX_BREAK);
        }
        splx(s);
}