istallion.c

powerpc内核mpc8241linux系统下char驱动程序

	unsigned int		head, tail, len;
	unsigned long		flags;

#if DEBUG
	printk("stli_writeroom(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return(0);
	if (tty == stli_txcooktty) {
		if (stli_txcookrealsize != 0) {
			len = stli_txcookrealsize - stli_txcooksize;
			return(len);
		}
	}

	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return(0);
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return(0);
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return(0);

	save_flags(flags);
	cli();
	EBRDENABLE(brdp);
	rp = &((volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr))->txq;
	head = (unsigned int) rp->head;
	tail = (unsigned int) rp->tail;
	if (tail != ((unsigned int) rp->tail))
		tail = (unsigned int) rp->tail;
	len = (head >= tail) ? (portp->txsize - (head - tail)) : (tail - head);
	len--;
	EBRDDISABLE(brdp);
	restore_flags(flags);

	if (tty == stli_txcooktty) {
		stli_txcookrealsize = len;
		len -= stli_txcooksize;
	}
	return(len);
}

/*****************************************************************************/

/*
 *	Return the number of characters in the transmit buffer. Normally we
 *	will return the number of chars in the shared memory ring queue.
 *	We need to kludge around the case where the shared memory buffer is
 *	empty but not all characters have drained yet, for this case just
 *	return that there is 1 character in the buffer!
 */

static int stli_charsinbuffer(struct tty_struct *tty)
{
	volatile cdkasyrq_t	*rp;
	stliport_t		*portp;
	stlibrd_t		*brdp;
	unsigned int		head, tail, len;
	unsigned long		flags;

#if DEBUG
	printk("stli_charsinbuffer(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return(0);
	if (tty == stli_txcooktty)
		stli_flushchars(tty);
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return(0);
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return(0);
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return(0);

	save_flags(flags);
	cli();
	EBRDENABLE(brdp);
	rp = &((volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr))->txq;
	head = (unsigned int) rp->head;
	tail = (unsigned int) rp->tail;
	if (tail != ((unsigned int) rp->tail))
		tail = (unsigned int) rp->tail;
	len = (head >= tail) ? (head - tail) : (portp->txsize - (tail - head));
	if ((len == 0) && test_bit(ST_TXBUSY, &portp->state))
		len = 1;
	EBRDDISABLE(brdp);
	restore_flags(flags);

	return(len);
}

/*****************************************************************************/

/*
 *	Generate the serial struct info.
 */

static void stli_getserial(stliport_t *portp, struct serial_struct *sp)
{
	struct serial_struct	sio;
	stlibrd_t		*brdp;

#if DEBUG
	printk("stli_getserial(portp=%x,sp=%x)\n", (int) portp, (int) sp);
#endif

	memset(&sio, 0, sizeof(struct serial_struct));
	sio.type = PORT_UNKNOWN;
	sio.line = portp->portnr;
	sio.irq = 0;
	sio.flags = portp->flags;
	sio.baud_base = portp->baud_base;
	sio.close_delay = portp->close_delay;
	sio.closing_wait = portp->closing_wait;
	sio.custom_divisor = portp->custom_divisor;
	sio.xmit_fifo_size = 0;
	sio.hub6 = 0;

	brdp = stli_brds[portp->brdnr];
	if (brdp != (stlibrd_t *) NULL)
		sio.port = brdp->iobase;
		
	copy_to_user(sp, &sio, sizeof(struct serial_struct));
}

/*****************************************************************************/

/*
 *	Set port according to the serial struct info.
 *	At this point we do not do any auto-configure stuff, so we will
 *	just quietly ignore any requests to change irq, etc.
 */

static int stli_setserial(stliport_t *portp, struct serial_struct *sp)
{
	struct serial_struct	sio;
	int			rc;

#if DEBUG
	printk("stli_setserial(portp=%x,sp=%x)\n", (int) portp, (int) sp);
#endif

	copy_from_user(&sio, sp, sizeof(struct serial_struct));
	if (!capable(CAP_SYS_ADMIN)) {
		if ((sio.baud_base != portp->baud_base) ||
		    (sio.close_delay != portp->close_delay) ||
		    ((sio.flags & ~ASYNC_USR_MASK) !=
		    (portp->flags & ~ASYNC_USR_MASK)))
			return(-EPERM);
	} 

	portp->flags = (portp->flags & ~ASYNC_USR_MASK) |
		(sio.flags & ASYNC_USR_MASK);
	portp->baud_base = sio.baud_base;
	portp->close_delay = sio.close_delay;
	portp->closing_wait = sio.closing_wait;
	portp->custom_divisor = sio.custom_divisor;

	if ((rc = stli_setport(portp)) < 0)
		return(rc);
	return(0);
}

/*****************************************************************************/

static int stli_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg)
{
	stliport_t	*portp;
	stlibrd_t	*brdp;
	unsigned long	lval;
	unsigned int	ival;
	int		rc;

#if DEBUG
	printk("stli_ioctl(tty=%x,file=%x,cmd=%x,arg=%x)\n",
		(int) tty, (int) file, cmd, (int) arg);
#endif

	if (tty == (struct tty_struct *) NULL)
		return(-ENODEV);
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return(-ENODEV);
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return(0);
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return(0);

	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
 	    (cmd != COM_GETPORTSTATS) && (cmd != COM_CLRPORTSTATS)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
			return(-EIO);
	}

	rc = 0;

	switch (cmd) {
	case TIOCGSOFTCAR:
		rc = put_user(((tty->termios->c_cflag & CLOCAL) ? 1 : 0),
			(unsigned int *) arg);
		break;
	case TIOCSSOFTCAR:
		if ((rc = verify_area(VERIFY_READ, (void *) arg,
		    sizeof(unsigned int))) == 0) {
			get_user(ival, (unsigned int *) arg);
			tty->termios->c_cflag =
				(tty->termios->c_cflag & ~CLOCAL) |
				(ival ? CLOCAL : 0);
		}
		break;
	case TIOCMGET:
		if ((rc = verify_area(VERIFY_WRITE, (void *) arg,
		    sizeof(unsigned int))) == 0) {
			if ((rc = stli_cmdwait(brdp, portp, A_GETSIGNALS,
			    &portp->asig, sizeof(asysigs_t), 1)) < 0)
				return(rc);
			lval = stli_mktiocm(portp->asig.sigvalue);
			put_user(lval, (unsigned int *) arg);
		}
		break;
	case TIOCMBIS:
		if ((rc = verify_area(VERIFY_READ, (void *) arg,
		    sizeof(unsigned int))) == 0) {
			get_user(ival, (unsigned int *) arg);
			stli_mkasysigs(&portp->asig,
				((ival & TIOCM_DTR) ? 1 : -1),
				((ival & TIOCM_RTS) ? 1 : -1));
			rc = stli_cmdwait(brdp, portp, A_SETSIGNALS,
				&portp->asig, sizeof(asysigs_t), 0);
		}
		break;
	case TIOCMBIC:
		if ((rc = verify_area(VERIFY_READ, (void *) arg,
		    sizeof(unsigned int))) == 0) {
			get_user(ival, (unsigned int *) arg);
			stli_mkasysigs(&portp->asig,
				((ival & TIOCM_DTR) ? 0 : -1),
				((ival & TIOCM_RTS) ? 0 : -1));
			rc = stli_cmdwait(brdp, portp, A_SETSIGNALS,
				&portp->asig, sizeof(asysigs_t), 0);
		}
		break;
	case TIOCMSET:
		if ((rc = verify_area(VERIFY_READ, (void *) arg,
		    sizeof(unsigned int))) == 0) {
			get_user(ival, (unsigned int *) arg);
			stli_mkasysigs(&portp->asig,
				((ival & TIOCM_DTR) ? 1 : 0),
				((ival & TIOCM_RTS) ? 1 : 0));
			rc = stli_cmdwait(brdp, portp, A_SETSIGNALS,
				&portp->asig, sizeof(asysigs_t), 0);
		}
		break;
	case TIOCGSERIAL:
		if ((rc = verify_area(VERIFY_WRITE, (void *) arg,
		    sizeof(struct serial_struct))) == 0)
			stli_getserial(portp, (struct serial_struct *) arg);
		break;
	case TIOCSSERIAL:
		if ((rc = verify_area(VERIFY_READ, (void *) arg,
		    sizeof(struct serial_struct))) == 0)
			rc = stli_setserial(portp, (struct serial_struct *)arg);
		break;
	case STL_GETPFLAG:
		if ((rc = verify_area(VERIFY_WRITE, (void *) arg,
		    sizeof(unsigned long))) == 0)
			put_user(portp->pflag, (unsigned int *) arg);
		break;
	case STL_SETPFLAG:
		if ((rc = verify_area(VERIFY_READ, (void *) arg,
		    sizeof(unsigned long))) == 0) {
			get_user(portp->pflag, (unsigned int *) arg);
			stli_setport(portp);
		}
		break;
	case COM_GETPORTSTATS:
		if ((rc = verify_area(VERIFY_WRITE, (void *) arg,
		    sizeof(comstats_t))) == 0)
			rc = stli_getportstats(portp, (comstats_t *) arg);
		break;
	case COM_CLRPORTSTATS:
		if ((rc = verify_area(VERIFY_WRITE, (void *) arg,
		    sizeof(comstats_t))) == 0)
			rc = stli_clrportstats(portp, (comstats_t *) arg);
		break;
	case TIOCSERCONFIG:
	case TIOCSERGWILD:
	case TIOCSERSWILD:
	case TIOCSERGETLSR:
	case TIOCSERGSTRUCT:
	case TIOCSERGETMULTI:
	case TIOCSERSETMULTI:
	default:
		rc = -ENOIOCTLCMD;
		break;
	}

	return(rc);
}

/*****************************************************************************/

/*
 *	This routine assumes that we have user context and can sleep.
 *	Looks like it is true for the current ttys implementation..!!
 */

static void stli_settermios(struct tty_struct *tty, struct termios *old)
{
	stliport_t	*portp;
	stlibrd_t	*brdp;
	struct termios	*tiosp;
	asyport_t	aport;

#if DEBUG
	printk("stli_settermios(tty=%x,old=%x)\n", (int) tty, (int) old);
#endif

	if (tty == (struct tty_struct *) NULL)
		return;
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return;
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return;

	tiosp = tty->termios;
	if ((tiosp->c_cflag == old->c_cflag) &&
	    (tiosp->c_iflag == old->c_iflag))
		return;

	stli_mkasyport(portp, &aport, tiosp);
	stli_cmdwait(brdp, portp, A_SETPORT, &aport, sizeof(asyport_t), 0);
	stli_mkasysigs(&portp->asig, ((tiosp->c_cflag & CBAUD) ? 1 : 0), -1);
	stli_cmdwait(brdp, portp, A_SETSIGNALS, &portp->asig,
		sizeof(asysigs_t), 0);
	if ((old->c_cflag & CRTSCTS) && ((tiosp->c_cflag & CRTSCTS) == 0))
		tty->hw_stopped = 0;
	if (((old->c_cflag & CLOCAL) == 0) && (tiosp->c_cflag & CLOCAL))
		wake_up_interruptible(&portp->open_wait);
}

/*****************************************************************************/

/*
 *	Attempt to flow control who ever is sending us data. We won't really
 *	do any flow control action here. We can't directly, and even if we
 *	wanted to we would have to send a command to the slave. The slave
 *	knows how to flow control, and will do so when its buffers reach its
 *	internal high water marks. So what we will do is set a local state
 *	bit that will stop us sending any RX data up from the poll routine
 *	(which is the place where RX data from the slave is handled).
 */

static void stli_throttle(struct tty_struct *tty)
{
	stliport_t	*portp;

#if DEBUG
	printk("stli_throttle(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return;
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;

	set_bit(ST_RXSTOP, &portp->state);
}

/*****************************************************************************/

/*
 *	Unflow control the device sending us data... That means that all
 *	we have to do is clear the RXSTOP state bit. The next poll call
 *	will then be able to pass the RX data back up.
 */

static void stli_unthrottle(struct tty_struct *tty)
{
	stliport_t	*portp;

#if DEBUG
	printk("stli_unthrottle(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return;
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;

	clear_bit(ST_RXSTOP, &portp->state);
}

/*****************************************************************************/

/*
 *	Stop the transmitter. Basically to do this we will just turn TX
 *	interrupts off.
 */

static void stli_stop(struct tty_struct *tty)
{
	stlibrd_t	*brdp;
	stliport_t	*portp;
	asyctrl_t	actrl;

#if DEBUG
	printk("stli_stop(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return;
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return;
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return;

	memset(&actrl, 0, sizeof(asyctrl_t));
	actrl.txctrl = CT_STOPFLOW;
#if 0
	stli_cmdwait(brdp, portp, A_PORTCTRL, &actrl, sizeof(asyctrl_t), 0);
#endif
}

/*****************************************************************************/

/*
 *	Start the transmitter again. Just turn TX interrupts back on.
 */

static void stli_start(struct tty_struct *tty)
{
	stliport_t	*portp;
	stlibrd_t	*brdp;
	asyctrl_t	actrl;

#if DEBUG
	printk("stli_start(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return;
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return;
	brdp = stli_brds[portp->brdnr];
	if (br