/*      $NetBSD: ppi.c,v 1.25 2019/11/12 13:17:44 msaitoh Exp $ */

/*-
 * Copyright (c) 1996-2003 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) 1982, 1990, 1993
 *      The Regents of the University of California.  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. 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.
 *
 *      @(#)ppi.c       8.1 (Berkeley) 6/16/93
 */

/*
 * Printer/Plotter GPIB interface
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ppi.c,v 1.25 2019/11/12 13:17:44 msaitoh Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/proc.h>
#include <sys/uio.h>

#include <dev/gpib/gpibvar.h>

#include <dev/gpib/ppiio.h>

#include "ioconf.h"

struct  ppi_softc {
        device_t sc_dev;
        gpib_chipset_tag_t sc_ic;
        gpib_handle_t sc_hdl;

        int sc_address;                 /* GPIB address */
        int     sc_flags;
        int     sc_sec;
        struct  ppiparam sc_param;
#define sc_burst sc_param.burst
#define sc_timo  sc_param.timo
#define sc_delay sc_param.delay
        struct  callout sc_timo_ch;
        struct  callout sc_start_ch;
};

/* sc_flags values */
#define PPIF_ALIVE      0x01
#define PPIF_OPEN       0x02
#define PPIF_UIO        0x04
#define PPIF_TIMO       0x08
#define PPIF_DELAY      0x10

int     ppimatch(device_t, cfdata_t, void *);
void    ppiattach(device_t, device_t, void *);

CFATTACH_DECL_NEW(ppi, sizeof(struct ppi_softc),
        ppimatch, ppiattach, NULL, NULL);

void    ppicallback(void *, int);
void    ppistart(void *);

void    ppitimo(void *);
int     ppirw(dev_t, struct uio *);
int     ppihztoms(int);
int     ppimstohz(int);

dev_type_open(ppiopen);
dev_type_close(ppiclose);
dev_type_read(ppiread);
dev_type_write(ppiwrite);
dev_type_ioctl(ppiioctl);

const struct cdevsw ppi_cdevsw = {
        .d_open = ppiopen,
        .d_close = ppiclose,
        .d_read = ppiread,
        .d_write = ppiwrite,
        .d_ioctl = ppiioctl,
        .d_stop = nostop,
        .d_tty = notty,
        .d_poll = nopoll,
        .d_mmap = nommap,
        .d_kqfilter = nokqfilter,
        .d_discard = nodiscard,
        .d_flag = D_OTHER
};

#define UNIT(x)         minor(x)

#ifdef DEBUG
int     ppidebug = 0x80;
#define PDB_FOLLOW      0x01
#define PDB_IO          0x02
#define PDB_NOCHECK     0x80
#define DPRINTF(mask, str)      if (ppidebug & (mask)) printf str
#else
#define DPRINTF(mask, str)      /* nothing */
#endif

int
ppimatch(device_t parent, cfdata_t match, void *aux)
{

        return (1);
}

void
ppiattach(device_t parent, device_t self, void *aux)
{
        struct ppi_softc *sc = device_private(self);
        struct gpib_attach_args *ga = aux;

        printf("\n");

        sc->sc_dev = self;
        sc->sc_ic = ga->ga_ic;
        sc->sc_address = ga->ga_address;

        callout_init(&sc->sc_timo_ch, 0);
        callout_init(&sc->sc_start_ch, 0);

        if (gpibregister(sc->sc_ic, sc->sc_address, ppicallback, sc,
            &sc->sc_hdl)) {
                aprint_error_dev(sc->sc_dev, "can't register callback\n");
                return;
        }

        sc->sc_flags = PPIF_ALIVE;
}

int
ppiopen(dev_t dev, int flags, int fmt, struct lwp *l)
{
        struct ppi_softc *sc;

        sc = device_lookup_private(&ppi_cd, UNIT(dev));
        if (sc == NULL)
                return (ENXIO);

        if ((sc->sc_flags & PPIF_ALIVE) == 0)
                return (ENXIO);

        DPRINTF(PDB_FOLLOW, ("ppiopen(%" PRIx64 ", %x): flags %x\n",
            dev, flags, sc->sc_flags));

        if (sc->sc_flags & PPIF_OPEN)
                return (EBUSY);
        sc->sc_flags |= PPIF_OPEN;
        sc->sc_burst = PPI_BURST;
        sc->sc_timo = ppimstohz(PPI_TIMO);
        sc->sc_delay = ppimstohz(PPI_DELAY);
        sc->sc_sec = -1;
        return (0);
}

int
ppiclose(dev_t dev, int flags, int fmt, struct lwp *l)
{
        struct ppi_softc *sc;

        sc = device_lookup_private(&ppi_cd, UNIT(dev));

        DPRINTF(PDB_FOLLOW, ("ppiclose(%" PRIx64 ", %x): flags %x\n",
                       dev, flags, sc->sc_flags));

        sc->sc_flags &= ~PPIF_OPEN;
        return (0);
}

void
ppicallback(void *v, int action)
{
        struct ppi_softc *sc = v;

        DPRINTF(PDB_FOLLOW, ("ppicallback: v=%p, action=%d\n", v, action));

        switch (action) {
        case GPIBCBF_START:
                ppistart(sc);
        case GPIBCBF_INTR:
                /* no-op */
                break;
#ifdef DEBUG
        default:
                DPRINTF(PDB_FOLLOW, ("ppicallback: unknown action %d\n",
                    action));
                break;
#endif
        }
}

void
ppistart(void *v)
{
        struct ppi_softc *sc = v;

        DPRINTF(PDB_FOLLOW, ("ppistart(%x)\n", device_unit(sc->sc_dev)));

        sc->sc_flags &= ~PPIF_DELAY;
        wakeup(sc);
}

void
ppitimo(void *arg)
{
        struct ppi_softc *sc = arg;

        DPRINTF(PDB_FOLLOW, ("ppitimo(%x)\n", device_unit(sc->sc_dev)));

        sc->sc_flags &= ~(PPIF_UIO|PPIF_TIMO);
        wakeup(sc);
}

int
ppiread(dev_t dev, struct uio *uio, int flags)
{

        DPRINTF(PDB_FOLLOW, ("ppiread(%" PRIx64 ", %p)\n", dev, uio));

        return (ppirw(dev, uio));
}

int
ppiwrite(dev_t dev, struct uio *uio, int flags)
{

        DPRINTF(PDB_FOLLOW, ("ppiwrite(%" PRIx64 ", %p)\n", dev, uio));

        return (ppirw(dev, uio));
}

int
ppirw(dev_t dev, struct uio *uio)
{
        struct ppi_softc *sc = device_lookup_private(&ppi_cd, UNIT(dev));
        int s1, s2, len, cnt;
        char *cp;
        int error = 0, gotdata = 0;
        int buflen, address;
        char *buf;

        if (uio->uio_resid == 0)
                return (0);

        address = sc->sc_address;

        DPRINTF(PDB_FOLLOW|PDB_IO,
            ("ppirw(%" PRIx64 ", %p, %c): burst %d, timo %d, resid %x\n",
            dev, uio, uio->uio_rw == UIO_READ ? 'R' : 'W',
            sc->sc_burst, sc->sc_timo, uio->uio_resid));

        buflen = uimin(sc->sc_burst, uio->uio_resid);
        buf = (char *)malloc(buflen, M_DEVBUF, M_WAITOK);
        sc->sc_flags |= PPIF_UIO;
        if (sc->sc_timo > 0) {
                sc->sc_flags |= PPIF_TIMO;
                callout_reset(&sc->sc_timo_ch, sc->sc_timo, ppitimo, sc);
        }
        len = cnt = 0;
        while (uio->uio_resid > 0) {
                len = uimin(buflen, uio->uio_resid);
                cp = buf;
                if (uio->uio_rw == UIO_WRITE) {
                        error = uiomove(cp, len, uio);
                        if (error)
                                break;
                }
again:
                s1 = splsoftclock();
                s2 = splbio();
                if (sc->sc_flags & PPIF_UIO) {
                        if (gpibrequest(sc->sc_ic, sc->sc_hdl) == 0)
                                (void) tsleep(sc, PRIBIO + 1, "ppirw", 0);
                }
                /*
                 * Check if we timed out during sleep or uiomove
                 */
                splx(s2);
                if ((sc->sc_flags & PPIF_UIO) == 0) {
                        DPRINTF(PDB_IO,
                            ("ppirw: uiomove/sleep timo, flags %x\n",
                            sc->sc_flags));
                        if (sc->sc_flags & PPIF_TIMO) {
                                callout_stop(&sc->sc_timo_ch);
                                sc->sc_flags &= ~PPIF_TIMO;
                        }
                        splx(s1);
                        break;
                }
                splx(s1);
                /*
                 * Perform the operation
                 */
                if (uio->uio_rw == UIO_WRITE)
                        cnt = gpibsend(sc->sc_ic, address, sc->sc_sec,
                            cp, len);
                else
                        cnt = gpibrecv(sc->sc_ic, address, sc->sc_sec,
                            cp, len);
                s1 = splbio();
                gpibrelease(sc->sc_ic, sc->sc_hdl);
                DPRINTF(PDB_IO, ("ppirw: %s(%d, %x, %p, %d) -> %d\n",
                    uio->uio_rw == UIO_READ ? "recv" : "send",
                    address, sc->sc_sec, cp, len, cnt));
                splx(s1);
                if (uio->uio_rw == UIO_READ) {
                        if (cnt) {
                                error = uiomove(cp, cnt, uio);
                                if (error)
                                        break;
                                gotdata++;
                        }
                        /*
                         * Didn't get anything this time, but did in the past.
                         * Consider us done.
                         */
                        else if (gotdata)
                                break;
                }
                s1 = splsoftclock();
                /*
                 * Operation timeout (or non-blocking), quit now.
                 */
                if ((sc->sc_flags & PPIF_UIO) == 0) {
                        DPRINTF(PDB_IO, ("ppirw: timeout/done\n"));
                        splx(s1);
                        break;
                }
                /*
                 * Implement inter-read delay
                 */
                if (sc->sc_delay > 0) {
                        sc->sc_flags |= PPIF_DELAY;
                        callout_reset(&sc->sc_start_ch, sc->sc_delay,
                            ppistart, sc);
                        error = tsleep(sc, (PCATCH|PZERO) + 1, "gpib", 0);
                        if (error) {
                                splx(s1);
                                break;
                        }
                }
                splx(s1);
                /*
                 * Must not call uiomove again til we've used all data
                 * that we already grabbed.
                 */
                if (uio->uio_rw == UIO_WRITE && cnt != len) {
                        cp += cnt;
                        len -= cnt;
                        cnt = 0;
                        goto again;
                }
        }
        s1 = splsoftclock();
        if (sc->sc_flags & PPIF_TIMO) {
                callout_stop(&sc->sc_timo_ch);
                sc->sc_flags &= ~PPIF_TIMO;
        }
        if (sc->sc_flags & PPIF_DELAY) {
                callout_stop(&sc->sc_start_ch);
                sc->sc_flags &= ~PPIF_DELAY;
        }
        splx(s1);
        /*
         * Adjust for those chars that we uiomove'ed but never wrote
         */
        if (uio->uio_rw == UIO_WRITE && cnt != len) {
                uio->uio_resid += (len - cnt);
                DPRINTF(PDB_IO, ("ppirw: short write, adjust by %d\n",
                    len - cnt));
        }
        free(buf, M_DEVBUF);
        DPRINTF(PDB_FOLLOW|PDB_IO, ("ppirw: return %d, resid %d\n",
            error, uio->uio_resid));
        return (error);
}

int
ppiioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
{
        struct ppi_softc *sc = device_lookup_private(&ppi_cd, UNIT(dev));
        struct ppiparam *pp, *upp;
        int error = 0;

        switch (cmd) {
        case PPIIOCGPARAM:
                pp = &sc->sc_param;
                upp = (struct ppiparam *)data;
                upp->burst = pp->burst;
                upp->timo = ppihztoms(pp->timo);
                upp->delay = ppihztoms(pp->delay);
                break;
        case PPIIOCSPARAM:
                pp = &sc->sc_param;
                upp = (struct ppiparam *)data;
                if (upp->burst < PPI_BURST_MIN || upp->burst > PPI_BURST_MAX ||
                    upp->delay < PPI_DELAY_MIN || upp->delay > PPI_DELAY_MAX)
                        return (EINVAL);
                pp->burst = upp->burst;
                pp->timo = ppimstohz(upp->timo);
                pp->delay = ppimstohz(upp->delay);
                break;
        case PPIIOCSSEC:
                sc->sc_sec = *(int *)data;
                break;
        default:
                return (EINVAL);
        }
        return (error);
}

int
ppihztoms(int h)
{
        extern int hz;
        int m = h;

        if (m > 0)
                m = m * 1000 / hz;
        return (m);
}

int
ppimstohz(int m)
{
        extern int hz;
        int h = m;

        if (h > 0) {
                h = h * hz / 1000;
                if (h == 0)
                        h = 1000 / hz;
        }
        return (h);
}