istallion.c

linux 内核源代码

			set_bit(ST_DOSIGS, &portp->state);
		else
			stli_sendcmd(brdp, portp, A_SETSIGNALS, &portp->asig,
				sizeof(asysigs_t), 0);
	}
	clear_bit(ST_TXBUSY, &portp->state);
	clear_bit(ST_RXSTOP, &portp->state);
	set_bit(TTY_IO_ERROR, &tty->flags);
	if (tty->ldisc.flush_buffer)
		(tty->ldisc.flush_buffer)(tty);
	set_bit(ST_DOFLUSHRX, &portp->state);
	stli_flushbuffer(tty);

	tty->closing = 0;
	portp->tty = NULL;

	if (portp->openwaitcnt) {
		if (portp->close_delay)
			msleep_interruptible(jiffies_to_msecs(portp->close_delay));
		wake_up_interruptible(&portp->open_wait);
	}

	portp->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&portp->close_wait);
}

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

/*
 *	Carry out first open operations on a port. This involves a number of
 *	commands to be sent to the slave. We need to open the port, set the
 *	notification events, set the initial port settings, get and set the
 *	initial signal values. We sleep and wait in between each one. But
 *	this still all happens pretty quickly.
 */

static int stli_initopen(struct stlibrd *brdp, struct stliport *portp)
{
	struct tty_struct *tty;
	asynotify_t nt;
	asyport_t aport;
	int rc;

	if ((rc = stli_rawopen(brdp, portp, 0, 1)) < 0)
		return rc;

	memset(&nt, 0, sizeof(asynotify_t));
	nt.data = (DT_TXLOW | DT_TXEMPTY | DT_RXBUSY | DT_RXBREAK);
	nt.signal = SG_DCD;
	if ((rc = stli_cmdwait(brdp, portp, A_SETNOTIFY, &nt,
	    sizeof(asynotify_t), 0)) < 0)
		return rc;

	tty = portp->tty;
	if (tty == NULL)
		return -ENODEV;
	stli_mkasyport(portp, &aport, tty->termios);
	if ((rc = stli_cmdwait(brdp, portp, A_SETPORT, &aport,
	    sizeof(asyport_t), 0)) < 0)
		return rc;

	set_bit(ST_GETSIGS, &portp->state);
	if ((rc = stli_cmdwait(brdp, portp, A_GETSIGNALS, &portp->asig,
	    sizeof(asysigs_t), 1)) < 0)
		return rc;
	if (test_and_clear_bit(ST_GETSIGS, &portp->state))
		portp->sigs = stli_mktiocm(portp->asig.sigvalue);
	stli_mkasysigs(&portp->asig, 1, 1);
	if ((rc = stli_cmdwait(brdp, portp, A_SETSIGNALS, &portp->asig,
	    sizeof(asysigs_t), 0)) < 0)
		return rc;

	return 0;
}

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

/*
 *	Send an open message to the slave. This will sleep waiting for the
 *	acknowledgement, so must have user context. We need to co-ordinate
 *	with close events here, since we don't want open and close events
 *	to overlap.
 */

static int stli_rawopen(struct stlibrd *brdp, struct stliport *portp, unsigned long arg, int wait)
{
	cdkhdr_t __iomem *hdrp;
	cdkctrl_t __iomem *cp;
	unsigned char __iomem *bits;
	unsigned long flags;
	int rc;

/*
 *	Send a message to the slave to open this port.
 */

/*
 *	Slave is already closing this port. This can happen if a hangup
 *	occurs on this port. So we must wait until it is complete. The
 *	order of opens and closes may not be preserved across shared
 *	memory, so we must wait until it is complete.
 */
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CLOSING, &portp->state));
	if (signal_pending(current)) {
		return -ERESTARTSYS;
	}

/*
 *	Everything is ready now, so write the open message into shared
 *	memory. Once the message is in set the service bits to say that
 *	this port wants service.
 */
	spin_lock_irqsave(&brd_lock, flags);
	EBRDENABLE(brdp);
	cp = &((cdkasy_t __iomem *) EBRDGETMEMPTR(brdp, portp->addr))->ctrl;
	writel(arg, &cp->openarg);
	writeb(1, &cp->open);
	hdrp = (cdkhdr_t __iomem *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((unsigned char __iomem *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	writeb(readb(bits) | portp->portbit, bits);
	EBRDDISABLE(brdp);

	if (wait == 0) {
		spin_unlock_irqrestore(&brd_lock, flags);
		return 0;
	}

/*
 *	Slave is in action, so now we must wait for the open acknowledgment
 *	to come back.
 */
	rc = 0;
	set_bit(ST_OPENING, &portp->state);
	spin_unlock_irqrestore(&brd_lock, flags);

	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_OPENING, &portp->state));
	if (signal_pending(current))
		rc = -ERESTARTSYS;

	if ((rc == 0) && (portp->rc != 0))
		rc = -EIO;
	return rc;
}

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

/*
 *	Send a close message to the slave. Normally this will sleep waiting
 *	for the acknowledgement, but if wait parameter is 0 it will not. If
 *	wait is true then must have user context (to sleep).
 */

static int stli_rawclose(struct stlibrd *brdp, struct stliport *portp, unsigned long arg, int wait)
{
	cdkhdr_t __iomem *hdrp;
	cdkctrl_t __iomem *cp;
	unsigned char __iomem *bits;
	unsigned long flags;
	int rc;

/*
 *	Slave is already closing this port. This can happen if a hangup
 *	occurs on this port.
 */
	if (wait) {
		wait_event_interruptible(portp->raw_wait,
				!test_bit(ST_CLOSING, &portp->state));
		if (signal_pending(current)) {
			return -ERESTARTSYS;
		}
	}

/*
 *	Write the close command into shared memory.
 */
	spin_lock_irqsave(&brd_lock, flags);
	EBRDENABLE(brdp);
	cp = &((cdkasy_t __iomem *) EBRDGETMEMPTR(brdp, portp->addr))->ctrl;
	writel(arg, &cp->closearg);
	writeb(1, &cp->close);
	hdrp = (cdkhdr_t __iomem *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((unsigned char __iomem *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	writeb(readb(bits) |portp->portbit, bits);
	EBRDDISABLE(brdp);

	set_bit(ST_CLOSING, &portp->state);
	spin_unlock_irqrestore(&brd_lock, flags);

	if (wait == 0)
		return 0;

/*
 *	Slave is in action, so now we must wait for the open acknowledgment
 *	to come back.
 */
	rc = 0;
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CLOSING, &portp->state));
	if (signal_pending(current))
		rc = -ERESTARTSYS;

	if ((rc == 0) && (portp->rc != 0))
		rc = -EIO;
	return rc;
}

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

/*
 *	Send a command to the slave and wait for the response. This must
 *	have user context (it sleeps). This routine is generic in that it
 *	can send any type of command. Its purpose is to wait for that command
 *	to complete (as opposed to initiating the command then returning).
 */

static int stli_cmdwait(struct stlibrd *brdp, struct stliport *portp, unsigned long cmd, void *arg, int size, int copyback)
{
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CMDING, &portp->state));
	if (signal_pending(current))
		return -ERESTARTSYS;

	stli_sendcmd(brdp, portp, cmd, arg, size, copyback);

	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CMDING, &portp->state));
	if (signal_pending(current))
		return -ERESTARTSYS;

	if (portp->rc != 0)
		return -EIO;
	return 0;
}

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

/*
 *	Send the termios settings for this port to the slave. This sleeps
 *	waiting for the command to complete - so must have user context.
 */

static int stli_setport(struct stliport *portp)
{
	struct stlibrd *brdp;
	asyport_t aport;

	if (portp == NULL)
		return -ENODEV;
	if (portp->tty == NULL)
		return -ENODEV;
	if (portp->brdnr >= stli_nrbrds)
		return -ENODEV;
	brdp = stli_brds[portp->brdnr];
	if (brdp == NULL)
		return -ENODEV;

	stli_mkasyport(portp, &aport, portp->tty->termios);
	return(stli_cmdwait(brdp, portp, A_SETPORT, &aport, sizeof(asyport_t), 0));
}

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

/*
 *	Possibly need to wait for carrier (DCD signal) to come high. Say
 *	maybe because if we are clocal then we don't need to wait...
 */

static int stli_waitcarrier(struct stlibrd *brdp, struct stliport *portp, struct file *filp)
{
	unsigned long flags;
	int rc, doclocal;

	rc = 0;
	doclocal = 0;

	if (portp->tty->termios->c_cflag & CLOCAL)
		doclocal++;

	spin_lock_irqsave(&stli_lock, flags);
	portp->openwaitcnt++;
	if (! tty_hung_up_p(filp))
		portp->refcount--;
	spin_unlock_irqrestore(&stli_lock, flags);

	for (;;) {
		stli_mkasysigs(&portp->asig, 1, 1);
		if ((rc = stli_cmdwait(brdp, portp, A_SETSIGNALS,
		    &portp->asig, sizeof(asysigs_t), 0)) < 0)
			break;
		if (tty_hung_up_p(filp) ||
		    ((portp->flags & ASYNC_INITIALIZED) == 0)) {
			if (portp->flags & ASYNC_HUP_NOTIFY)
				rc = -EBUSY;
			else
				rc = -ERESTARTSYS;
			break;
		}
		if (((portp->flags & ASYNC_CLOSING) == 0) &&
		    (doclocal || (portp->sigs & TIOCM_CD))) {
			break;
		}
		if (signal_pending(current)) {
			rc = -ERESTARTSYS;
			break;
		}
		interruptible_sleep_on(&portp->open_wait);
	}

	spin_lock_irqsave(&stli_lock, flags);
	if (! tty_hung_up_p(filp))
		portp->refcount++;
	portp->openwaitcnt--;
	spin_unlock_irqrestore(&stli_lock, flags);

	return rc;
}

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

/*
 *	Write routine. Take the data and put it in the shared memory ring
 *	queue. If port is not already sending chars then need to mark the
 *	service bits for this port.
 */

static int stli_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
	cdkasy_t __iomem *ap;
	cdkhdr_t __iomem *hdrp;
	unsigned char __iomem *bits;
	unsigned char __iomem *shbuf;
	unsigned char *chbuf;
	struct stliport *portp;
	struct stlibrd *brdp;
	unsigned int len, stlen, head, tail, size;
	unsigned long flags;

	if (tty == stli_txcooktty)
		stli_flushchars(tty);
	portp = tty->driver_data;
	if (portp == NULL)
		return 0;
	if (portp->brdnr >= stli_nrbrds)
		return 0;
	brdp = stli_brds[portp->brdnr];
	if (brdp == NULL)
		return 0;
	chbuf = (unsigned char *) buf;

/*
 *	All data is now local, shove as much as possible into shared memory.
 */
	spin_lock_irqsave(&brd_lock, flags);
	EBRDENABLE(brdp);
	ap = (cdkasy_t __iomem *) EBRDGETMEMPTR(brdp, portp->addr);
	head = (unsigned int) readw(&ap->txq.head);
	tail = (unsigned int) readw(&ap->txq.tail);
	if (tail != ((unsigned int) readw(&ap->txq.tail)))
		tail = (unsigned int) readw(&ap->txq.tail);
	size = portp->txsize;
	if (head >= tail) {
		len = size - (head - tail) - 1;
		stlen = size - head;
	} else {
		len = tail - head - 1;
		stlen = len;
	}

	len = min(len, (unsigned int)count);
	count = 0;
	shbuf = (char __iomem *) EBRDGETMEMPTR(brdp, portp->txoffset);

	while (len > 0) {
		stlen = min(len, stlen);
		memcpy_toio(shbuf + head, chbuf, stlen);
		chbuf += stlen;
		len -= stlen;
		count += stlen;
		head += stlen;
		if (head >= size) {
			head = 0;
			stlen = tail;
		}
	}

	ap = (cdkasy_t __iomem *) EBRDGETMEMPTR(brdp, portp->addr);
	writew(head, &ap->txq.head);
	if (test_bit(ST_TXBUSY, &portp->state)) {
		if (readl(&ap->changed.data) & DT_TXEMPTY)
			writel(readl(&ap->changed.data) & ~DT_TXEMPTY, &ap->changed.data);
	}
	hdrp = (cdkhdr_t __iomem *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((unsigned char __iomem *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	writeb(readb(bits) | portp->portbit, bits);
	set_bit(ST_TXBUSY, &portp->state);
	EBRDDISABLE(brdp);
	spin_unlock_irqrestore(&brd_lock, flags);

	return(count);
}

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

/*
 *	Output a single character. We put it into a temporary local buffer
 *	(for speed) then write out that buffer when the flushchars routine
 *	is called. There is a safety catch here so that if some other port
 *	writes chars before the current buffer has been, then we write them
 *	first them do the new ports.
 */

static void stli_putchar(struct tty_struct *tty, unsigned char ch)
{
	if (tty != stli_txcooktty) {
		if (stli_txcooktty != NULL)
			stli_flushchars(stli_txcooktty);
		stli_txcooktty = tty;
	}

	stli_txcookbuf[stli_txcooksize++] = ch;
}

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

/*
 *	Transfer characters from the local TX cooking buffer to the board.
 *	We sort of ignore the tty that gets passed in here. We rely on the
 *	info stored with the TX cook buffer to tell us which port to flush
 *	the data on. In any case we clean out the TX cook buffer, for re-use
 *	by someone else.
 */

static void stli_flushchars(struct tty_struct *tty)
{
	cdkhdr_t __iomem *hdrp;
	unsigned char __iomem *bits;
	cdkasy_t __iomem *ap;
	struct tty_struct *cooktty;
	struct stliport *portp;
	struct stlibrd *brdp;
	unsigned int len, stlen, head, tail, size, count, cooksize;
	unsigned char *buf;
	unsigned char __iomem *shbuf;
	unsigned long flags;

	cooksize = stli_txcooksize;
	cooktty = stli_txcooktty;
	stli_txcooksize = 0;
	stli_txcookrealsize = 0;
	stli_txcooktty = NULL;

	if (tty == NULL)
		return;
	if (cooktty == NULL)
		return;