si.c

基于组件方式开发操作系统的OSKIT源代码

			DV_CHR, 0, 0, 0600, "ttylA%02d", y);
		sc->devfs_token[x].cual = devfs_add_devswf(
			&si_cdevsw, x + 0x20080,
			DV_CHR, 0, 0, 0600, "cualA%02d", y);
	}
	sc->control_token = 
		devfs_add_devswf(&si_cdevsw, 0x40000, DV_CHR, 0, 0, 0600, 
				 "si_control");
#endif
	return (1);
}

static	int
siopen(dev, flag, mode, p)
	dev_t dev;
	int flag, mode;
	struct proc *p;
{
	int oldspl, error;
	int card, port;
	register struct si_softc *sc;
	register struct tty *tp;
	volatile struct si_channel *ccbp;
	struct si_port *pp;
	int mynor = minor(dev);

	/* quickly let in /dev/si_control */
	if (IS_CONTROLDEV(mynor)) {
		if ((error = suser(p->p_ucred, &p->p_acflag)))
			return(error);
		return(0);
	}

	card = SI_CARD(mynor);
	if (card >= NSI)
		return (ENXIO);
	sc = &si_softc[card];

	if (sc->sc_type == SIEMPTY) {
		DPRINT((0, DBG_OPEN|DBG_FAIL, "si%d: type %s??\n",
			card, sc->sc_typename));
		return(ENXIO);
	}

	port = SI_PORT(mynor);
	if (port >= sc->sc_nport) {
		DPRINT((0, DBG_OPEN|DBG_FAIL, "si%d: nports %d\n",
			card, sc->sc_nport));
		return(ENXIO);
	}

#ifdef	POLL
	/*
	 * We've now got a device, so start the poller.
	 */
	if (init_finished == 0) {
		timeout(si_poll, (caddr_t)0L, si_pollrate);
		init_finished = 1;
	}
#endif

	/* initial/lock device */
	if (IS_STATE(mynor)) {
		return(0);
	}

	pp = sc->sc_ports + port;
	tp = pp->sp_tty;			/* the "real" tty */
	ccbp = pp->sp_ccb;			/* Find control block */
	DPRINT((pp, DBG_ENTRY|DBG_OPEN, "siopen(%x,%x,%x,%x)\n",
		dev, flag, mode, p));

	oldspl = spltty();			/* Keep others out */
	error = 0;

open_top:
	while (pp->sp_state & SS_DTR_OFF) {
		error = tsleep(&pp->sp_dtr_wait, TTIPRI|PCATCH, "sidtr", 0);
		if (error != 0)
			goto out;
	}

	if (tp->t_state & TS_ISOPEN) {
		/*
		 * The device is open, so everything has been initialised.
		 * handle conflicts.
		 */
		if (IS_CALLOUT(mynor)) {
			if (!pp->sp_active_out) {
				error = EBUSY;
				goto out;
			}
		} else {
			if (pp->sp_active_out) {
				if (flag & O_NONBLOCK) {
					error = EBUSY;
					goto out;
				}
				error = tsleep(&pp->sp_active_out,
						TTIPRI|PCATCH, "sibi", 0);
				if (error != 0)
					goto out;
				goto open_top;
			}
		}
		if (tp->t_state & TS_XCLUDE && p->p_ucred->cr_uid != 0) {
			DPRINT((pp, DBG_OPEN|DBG_FAIL,
				"already open and EXCLUSIVE set\n"));
			error = EBUSY;
			goto out;
		}
	} else {
		/*
		 * The device isn't open, so there are no conflicts.
		 * Initialize it. Avoid sleep... :-)
		 */
		DPRINT((pp, DBG_OPEN, "first open\n"));
		tp->t_oproc = si_start;
		tp->t_param = siparam;
		tp->t_dev = dev;
		tp->t_termios = mynor & SI_CALLOUT_MASK
				? pp->sp_iout : pp->sp_iin;

		(void) si_modem(pp, SET, TIOCM_DTR|TIOCM_RTS);

		++pp->sp_wopeners;	/* in case of sleep in siparam */

		error = siparam(tp, &tp->t_termios);

		--pp->sp_wopeners;
		if (error != 0)
			goto out;
		/* XXX: we should goto_top if siparam slept */

		/* set initial DCD state */
		pp->sp_last_hi_ip = ccbp->hi_ip;
		if ((pp->sp_last_hi_ip & IP_DCD) || IS_CALLOUT(mynor)) {
			(*linesw[tp->t_line].l_modem)(tp, 1);
		}
	}

	/* whoops! we beat the close! */
	if (pp->sp_state & SS_CLOSING) {
		/* try and stop it from proceeding to bash the hardware */
		pp->sp_state &= ~SS_CLOSING;
	}

	/*
	 * Wait for DCD if necessary
	 */
	if (!(tp->t_state & TS_CARR_ON)
	    && !IS_CALLOUT(mynor)
	    && !(tp->t_cflag & CLOCAL)
	    && !(flag & O_NONBLOCK)) {
		++pp->sp_wopeners;
		DPRINT((pp, DBG_OPEN, "sleeping for carrier\n"));
		error = tsleep(TSA_CARR_ON(tp), TTIPRI|PCATCH, "sidcd", 0);
		--pp->sp_wopeners;
		if (error != 0)
			goto out;
		goto open_top;
	}

	error = (*linesw[tp->t_line].l_open)(dev, tp);
	si_disc_optim(tp, &tp->t_termios, pp);
	if (tp->t_state & TS_ISOPEN && IS_CALLOUT(mynor))
		pp->sp_active_out = TRUE;

	pp->sp_state |= SS_OPEN;	/* made it! */

out:
	splx(oldspl);

	DPRINT((pp, DBG_OPEN, "leaving siopen\n"));

	if (!(tp->t_state & TS_ISOPEN) && pp->sp_wopeners == 0)
		sihardclose(pp);

	return(error);
}

static	int
siclose(dev, flag, mode, p)
	dev_t dev;
	int flag, mode;
	struct proc *p;
{
	register struct si_port *pp;
	register struct tty *tp;
	int oldspl;
	int error = 0;
	int mynor = minor(dev);

	if (IS_SPECIAL(mynor))
		return(0);

	oldspl = spltty();

	pp = MINOR2PP(mynor);
	tp = pp->sp_tty;

	DPRINT((pp, DBG_ENTRY|DBG_CLOSE, "siclose(%x,%x,%x,%x) sp_state:%x\n",
		dev, flag, mode, p, pp->sp_state));

	/* did we sleep and loose a race? */
	if (pp->sp_state & SS_CLOSING) {
		/* error = ESOMETING? */
		goto out;
	}

	/* begin race detection.. */
	pp->sp_state |= SS_CLOSING;

	si_write_enable(pp, 0);		/* block writes for ttywait() */

	/* THIS MAY SLEEP IN TTYWAIT!!! */
	(*linesw[tp->t_line].l_close)(tp, flag);

	si_write_enable(pp, 1);

	/* did we sleep and somebody started another open? */
	if (!(pp->sp_state & SS_CLOSING)) {
		/* error = ESOMETING? */
		goto out;
	}
	/* ok. we are now still on the right track.. nuke the hardware */

	if (pp->sp_state & SS_LSTART) {
		untimeout(si_lstart, (caddr_t)pp, pp->lstart_ch);
		pp->sp_state &= ~SS_LSTART;
	}

	sistop(tp, FREAD | FWRITE);

	sihardclose(pp);
	ttyclose(tp);
	pp->sp_state &= ~SS_OPEN;

out:
	DPRINT((pp, DBG_CLOSE|DBG_EXIT, "close done, returning\n"));
	splx(oldspl);
	return(error);
}

static void
sihardclose(pp)
	struct si_port *pp;
{
	int oldspl;
	struct tty *tp;
	volatile struct si_channel *ccbp;

	oldspl = spltty();

	tp = pp->sp_tty;
	ccbp = pp->sp_ccb;			/* Find control block */
	if (tp->t_cflag & HUPCL
	    || (!pp->sp_active_out
		&& !(ccbp->hi_ip & IP_DCD)
		&& !(pp->sp_iin.c_cflag && CLOCAL))
	    || !(tp->t_state & TS_ISOPEN)) {

		(void) si_modem(pp, BIC, TIOCM_DTR|TIOCM_RTS);
		(void) si_command(pp, FCLOSE, SI_NOWAIT);

		if (pp->sp_dtr_wait != 0) {
			timeout(sidtrwakeup, pp, pp->sp_dtr_wait);
			pp->sp_state |= SS_DTR_OFF;
		}

	}
	pp->sp_active_out = FALSE;
	wakeup((caddr_t)&pp->sp_active_out);
	wakeup(TSA_CARR_ON(tp));

	splx(oldspl);
}


/*
 * called at splsoftclock()...
 */
static void
sidtrwakeup(chan)
	void *chan;
{
	struct si_port *pp;
	int oldspl;

	oldspl = spltty();

	pp = (struct si_port *)chan;
	pp->sp_state &= ~SS_DTR_OFF;
	wakeup(&pp->sp_dtr_wait);

	splx(oldspl);
}

/*
 * User level stuff - read and write
 */
static	int
siread(dev, uio, flag)
	register dev_t dev;
	struct uio *uio;
	int flag;
{
	register struct tty *tp;
	int mynor = minor(dev);

	if (IS_SPECIAL(mynor)) {
		DPRINT((0, DBG_ENTRY|DBG_FAIL|DBG_READ, "siread(CONTROLDEV!!)\n"));
		return(ENODEV);
	}
	tp = MINOR2TP(mynor);
	DPRINT((TP2PP(tp), DBG_ENTRY|DBG_READ,
		"siread(%x,%x,%x)\n", dev, uio, flag));
	return ((*linesw[tp->t_line].l_read)(tp, uio, flag));
}


static	int
siwrite(dev, uio, flag)
	dev_t dev;
	struct uio *uio;
	int flag;
{
	register struct si_port *pp;
	register struct tty *tp;
	int error = 0;
	int mynor = minor(dev);
	int oldspl;

	if (IS_SPECIAL(mynor)) {
		DPRINT((0, DBG_ENTRY|DBG_FAIL|DBG_WRITE, "siwrite(CONTROLDEV!!)\n"));
		return(ENODEV);
	}
	pp = MINOR2PP(mynor);
	tp = pp->sp_tty;
	DPRINT((pp, DBG_WRITE, "siwrite(%x,%x,%x)\n", dev, uio, flag));

	oldspl = spltty();
	/*
	 * If writes are currently blocked, wait on the "real" tty
	 */
	while (pp->sp_state & SS_BLOCKWRITE) {
		pp->sp_state |= SS_WAITWRITE;
		DPRINT((pp, DBG_WRITE, "in siwrite, wait for SS_BLOCKWRITE to clear\n"));
		if ((error = ttysleep(tp, (caddr_t)pp, TTOPRI|PCATCH,
				     "siwrite", tp->t_timeout))) {
			if (error == EWOULDBLOCK)
				error = EIO;
			goto out;
		}
	}

	error = (*linesw[tp->t_line].l_write)(tp, uio, flag);
out:
	splx(oldspl);
	return (error);
}


static	struct tty *
sidevtotty(dev_t dev)
{
	struct si_port *pp;
	int mynor = minor(dev);
	struct si_softc *sc = &si_softc[SI_CARD(mynor)];

	if (IS_SPECIAL(mynor))
		return(NULL);
	if (SI_PORT(mynor) >= sc->sc_nport)
		return(NULL);
	pp = MINOR2PP(mynor);
	return (pp->sp_tty);
}

static	int
siioctl(dev, cmd, data, flag, p)
	dev_t dev;
	u_long cmd;
	caddr_t data;
	int flag;
	struct proc *p;
{
	struct si_port *pp;
	register struct tty *tp;
	int error;
	int mynor = minor(dev);
	int oldspl;
	int blocked = 0;
#if defined(COMPAT_43)
	u_long oldcmd;
	struct termios term;
#endif

	if (IS_SI_IOCTL(cmd))
		return(si_Sioctl(dev, cmd, data, flag, p));

	pp = MINOR2PP(mynor);
	tp = pp->sp_tty;

	DPRINT((pp, DBG_ENTRY|DBG_IOCTL, "siioctl(%x,%lx,%x,%x)\n",
		dev, cmd, data, flag));
	if (IS_STATE(mynor)) {
		struct termios *ct;

		switch (mynor & SI_STATE_MASK) {
		case SI_INIT_STATE_MASK:
			ct = IS_CALLOUT(mynor) ? &pp->sp_iout : &pp->sp_iin;
			break;
		case SI_LOCK_STATE_MASK:
			ct = IS_CALLOUT(mynor) ? &pp->sp_lout : &pp->sp_lin;
			break;
		default:
			return (ENODEV);
		}
		switch (cmd) {
		case TIOCSETA:
			error = suser(p->p_ucred, &p->p_acflag);
			if (error != 0)
				return (error);
			*ct = *(struct termios *)data;
			return (0);
		case TIOCGETA:
			*(struct termios *)data = *ct;
			return (0);
		case TIOCGETD:
			*(int *)data = TTYDISC;
			return (0);
		case TIOCGWINSZ:
			bzero(data, sizeof(struct winsize));
			return (0);
		default:
			return (ENOTTY);
		}
	}
	/*
	 * Do the old-style ioctl compat routines...
	 */
#if defined(COMPAT_43)
	term = tp->t_termios;
	oldcmd = cmd;
	error = ttsetcompat(tp, &cmd, data, &term);
	if (error != 0)
		return (error);
	if (cmd != oldcmd)
		data = (caddr_t)&term;
#endif
	/*
	 * Do the initial / lock state business
	 */
	if (cmd == TIOCSETA || cmd == TIOCSETAW || cmd == TIOCSETAF) {
		int     cc;
		struct termios *dt = (struct termios *)data;
		struct termios *lt = mynor & SI_CALLOUT_MASK
				     ? &pp->sp_lout : &pp->sp_lin;

		dt->c_iflag = (tp->t_iflag & lt->c_iflag)
			| (dt->c_iflag & ~lt->c_iflag);
		dt->c_oflag = (tp->t_oflag & lt->c_oflag)
			| (dt->c_oflag & ~lt->c_oflag);
		dt->c_cflag = (tp->t_cflag & lt->c_cflag)
			| (dt->c_cflag & ~lt->c_cflag);
		dt->c_lflag = (tp->t_lflag & lt->c_lflag)
			| (dt->c_lflag & ~lt->c_lflag);
		for (cc = 0; cc < NCCS; ++cc)
			if (lt->c_cc[cc] != 0)
				dt->c_cc[cc] = tp->t_cc[cc];
		if (lt->c_ispeed != 0)
			dt->c_ispeed = tp->t_ispeed;
		if (lt->c_ospeed != 0)
			dt->c_ospeed = tp->t_ospeed;
	}

	/*
	 * Block user-level writes to give the ttywait()
	 * a chance to completely drain for commands
	 * that require the port to be in a quiescent state.
	 */
	switch (cmd) {
	case TIOCSETAW:
	case TIOCSETAF:
	case TIOCDRAIN:
#ifdef COMPAT_43
	case TIOCSETP:
#endif
		blocked++;	/* block writes for ttywait() and siparam() */
		si_write_enable(pp, 0);
	}

	error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
	if (error != ENOIOCTL)
		goto out;

	oldspl = spltty();

	error = ttioctl(tp, cmd, data, flag);
	si_disc_optim(tp, &tp->t_termios, pp);
	if (error != ENOIOCTL)
		goto outspl;

	switch (cmd) {
	case TIOCSBRK:
		si_command(pp, SBREAK, SI_WAIT);
		break;
	case TIOCCBRK:
		si_command(pp, EBREAK, SI_WAIT);
		break;
	case TIOCSDTR:
		(void) si_modem(pp, SET, TIOCM_DTR|TIOCM_RTS);
		break;
	case TIOCCDTR:
		(void) si_modem(pp, SET, 0);
		break;
	case TIOCMSET:
		(void) si_modem(pp, SET, *(int *)data);
		break;
	case TIOCMBIS:
		(void) si_modem(pp, BIS, *(int *)data);
		break;
	case TIOCMBIC:
		(void) si_modem(pp, BIC, *(int *)data);
		break;
	case TIOCMGET:
		*(int *)data = si_modem(pp, GET, 0);
		break;
	case TIOCMSDTRWAIT:
		/* must be root since the wait applies to following logins */
		error = suser(p->p_ucred, &p->p_acflag);
		if (error != 0) {
			goto outspl;
		}
		pp->sp_dtr_wait = *(int *)data * hz / 100;
		break;
	case TIOCMGDTRWAIT:
		*(int *)data = pp->sp_dtr_wait * 100 / hz;
		break;

	default:
		error = ENOTTY;
	}
	error = 0;
outspl:
	splx(oldspl);
out:
	DPRINT((pp, DBG_IOCTL|DBG_EXIT, "siioctl ret %d\n", error));
	if (blocked)
		si_write_enable(pp, 1);
	return(error);