/*      $NetBSD: ofcons.c,v 1.45 2014/07/25 08:10:37 dholland Exp $     */

/*
 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
 * Copyright (C) 1995, 1996 TooLs GmbH.
 * 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 product includes software developed by TooLs GmbH.
 * 4. The name of TooLs GmbH may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``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 TOOLS GMBH 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: ofcons.c,v 1.45 2014/07/25 08:10:37 dholland Exp $");

#include <sys/param.h>
#include <sys/conf.h>
#include <sys/device.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/callout.h>
#include <sys/tty.h>
#include <sys/kauth.h>

#include <dev/cons.h>

#include <dev/ofw/openfirm.h>

struct ofcons_softc {
        struct tty *of_tty;
        struct callout sc_poll_ch;
        int of_flags;
};
/* flags: */
#define OFPOLL          1

#define OFBURSTLEN      128     /* max number of bytes to write in one chunk */

cons_decl(ofcons_);

static int stdin, stdout;

static int ofcons_match(device_t, cfdata_t, void *);
static void ofcons_attach(device_t, device_t, void *);

CFATTACH_DECL_NEW(ofcons, sizeof(struct ofcons_softc),
    ofcons_match, ofcons_attach, NULL, NULL);

extern struct cfdriver ofcons_cd;

dev_type_open(ofcons_open);
dev_type_close(ofcons_close);
dev_type_read(ofcons_read);
dev_type_write(ofcons_write);
dev_type_ioctl(ofcons_ioctl);
dev_type_tty(ofcons_tty);
dev_type_poll(ofcons_poll);

const struct cdevsw ofcons_cdevsw = {
        .d_open = ofcons_open,
        .d_close = ofcons_close,
        .d_read = ofcons_read,
        .d_write = ofcons_write,
        .d_ioctl = ofcons_ioctl,
        .d_stop = nostop,
        .d_tty = ofcons_tty,
        .d_poll = ofcons_poll,
        .d_mmap = nommap,
        .d_kqfilter = ttykqfilter,
        .d_discard = nodiscard,
        .d_flag = D_TTY
};

static int ofcons_probe(void);

static int
ofcons_match(device_t parent, cfdata_t match, void *aux)
{
        struct ofbus_attach_args *oba = aux;

        if (strcmp(oba->oba_busname, "ofw"))
                return (0);
        if (!ofcons_probe())
                return 0;
        return OF_instance_to_package(stdin) == oba->oba_phandle
                || OF_instance_to_package(stdout) == oba->oba_phandle;
}

static void
ofcons_attach(device_t parent, device_t self, void *aux)
{
        struct ofcons_softc *sc = device_private(self);

        printf("\n");

        callout_init(&sc->sc_poll_ch, 0);
}

static void ofcons_start(struct tty *);
static int ofcons_param(struct tty *, struct termios *);
static void ofcons_pollin(void *);

int
ofcons_open(dev_t dev, int flag, int mode, struct lwp *l)
{
        struct ofcons_softc *sc;
        struct tty *tp;

        sc = device_lookup_private(&ofcons_cd, minor(dev));
        if (!sc)
                return ENXIO;
        if (!(tp = sc->of_tty))
                sc->of_tty = tp = tty_alloc();
        tp->t_oproc = ofcons_start;
        tp->t_param = ofcons_param;
        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;
                tp->t_cflag = TTYDEF_CFLAG;
                tp->t_lflag = TTYDEF_LFLAG;
                tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED;
                ofcons_param(tp, &tp->t_termios);
                ttsetwater(tp);
        }
        tp->t_state |= TS_CARR_ON;

        if (!(sc->of_flags & OFPOLL)) {
                sc->of_flags |= OFPOLL;
                callout_reset(&sc->sc_poll_ch, 1, ofcons_pollin, sc);
        }

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

int
ofcons_close(dev_t dev, int flag, int mode, struct lwp *l)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));
        struct tty *tp = sc->of_tty;

        callout_stop(&sc->sc_poll_ch);
        sc->of_flags &= ~OFPOLL;
        (*tp->t_linesw->l_close)(tp, flag);
        ttyclose(tp);
        return 0;
}

int
ofcons_read(dev_t dev, struct uio *uio, int flag)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));
        struct tty *tp = sc->of_tty;

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

int
ofcons_write(dev_t dev, struct uio *uio, int flag)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));
        struct tty *tp = sc->of_tty;

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

int
ofcons_poll(dev_t dev, int events, struct lwp *l)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));
        struct tty *tp = sc->of_tty;

        return ((*tp->t_linesw->l_poll)(tp, events, l));
}
int
ofcons_ioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));
        struct tty *tp = sc->of_tty;
        int error;

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

struct tty *
ofcons_tty(dev_t dev)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));

        return sc->of_tty;
}

static void
ofcons_start(struct tty *tp)
{
        int s, len;
        u_char buf[OFBURSTLEN];

        s = spltty();
        if (tp->t_state & (TS_TIMEOUT | TS_BUSY | TS_TTSTOP)) {
                splx(s);
                return;
        }
        tp->t_state |= TS_BUSY;
        splx(s);
        len = q_to_b(&tp->t_outq, buf, OFBURSTLEN);
        OF_write(stdout, buf, len);
        s = spltty();
        tp->t_state &= ~TS_BUSY;
        if (ttypull(tp)) {
                tp->t_state |= TS_TIMEOUT;
                callout_schedule(&tp->t_rstrt_ch, 1);
        }
        splx(s);
}

static int
ofcons_param(struct tty *tp, struct termios *t)
{
        tp->t_ispeed = t->c_ispeed;
        tp->t_ospeed = t->c_ospeed;
        tp->t_cflag = t->c_cflag;
        return 0;
}

static void
ofcons_pollin(void *aux)
{
        struct ofcons_softc *sc = aux;
        struct tty *tp = sc->of_tty;
        char ch;

        while (OF_read(stdin, &ch, 1) > 0) {
                if (tp && (tp->t_state & TS_ISOPEN))
                        (*tp->t_linesw->l_rint)(ch, tp);
        }
        callout_reset(&sc->sc_poll_ch, 1, ofcons_pollin, sc);
}

static int
ofcons_probe(void)
{
        int chosen;
        char stdinbuf[4], stdoutbuf[4];

        if (stdin)
                return 1;
        if ((chosen = OF_finddevice("/chosen")) == -1)
                return 0;
        if (OF_getprop(chosen, "stdin", stdinbuf, sizeof stdinbuf) !=
              sizeof stdinbuf ||
            OF_getprop(chosen, "stdout", stdoutbuf, sizeof stdoutbuf) !=
              sizeof stdoutbuf)
                return 0;

        /* Decode properties. */
        stdin = of_decode_int(stdinbuf);
        stdout = of_decode_int(stdoutbuf);

        return 1;
}

void
ofcons_cnprobe(struct consdev *cd)
{
        int maj;

        if (!ofcons_probe())
                return;

        maj = cdevsw_lookup_major(&ofcons_cdevsw);
        cd->cn_dev = makedev(maj, 0);
        cd->cn_pri = CN_INTERNAL;
}

void
ofcons_cninit(struct consdev *cd)
{
}

int
ofcons_cngetc(dev_t dev)
{
        unsigned char ch = '\0';
        int l;

        while ((l = OF_read(stdin, &ch, 1)) != 1)
                if (l != -2 && l != 0)
                        return -1;
        return ch;
}

void
ofcons_cnputc(dev_t dev, int c)
{
        char ch = c;

        OF_write(stdout, &ch, 1);
}

void
ofcons_cnpollc(dev_t dev, int on)
{
        struct ofcons_softc *sc = device_lookup_private(&ofcons_cd, minor(dev));

        if (!sc)
                return;
        if (on) {
                if (sc->of_flags & OFPOLL)
                        callout_stop(&sc->sc_poll_ch);
                sc->of_flags &= ~OFPOLL;
        } else {
                if (!(sc->of_flags & OFPOLL)) {
                        sc->of_flags |= OFPOLL;
                        callout_reset(&sc->sc_poll_ch, 1, ofcons_pollin, sc);
                }
        }
}