vacserial.c

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	unsigned long flags;
	
	if (serial_paranoia_check(info, tty->device, "rs_break"))
		return;

	if (!info->port)
		return;
	save_flags(flags); cli();
	if (break_state == -1)
		serial_outp(info, VAC_UART_MODE,
			   serial_inp(info, VAC_UART_MODE) | \
			    VAC_UART_MODE_SEND_BREAK);
	else
		serial_outp(info, VAC_UART_MODE,
			   serial_inp(info, VAC_UART_MODE) & \
			    ~VAC_UART_MODE_SEND_BREAK);
	restore_flags(flags);
}

static int rs_ioctl(struct tty_struct *tty, struct file * file,
		    unsigned int cmd, unsigned long arg)
{
	int error;
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	struct async_icount cprev, cnow;	/* kernel counter temps */
	struct serial_icounter_struct *p_cuser;	/* user space */
	unsigned long flags; 

	if (serial_paranoia_check(info, tty->device, "rs_ioctl"))
		return -ENODEV;

	if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
	    (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGSTRUCT) &&
	    (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
		if (tty->flags & (1 << TTY_IO_ERROR))
		    return -EIO;
	}
	
	switch (cmd) {
		case TIOCMGET:
			return get_modem_info(info, (unsigned int *) arg);
		case TIOCMBIS:
		case TIOCMBIC:
		case TIOCMSET:
			return set_modem_info(info, cmd, (unsigned int *) arg);
		case TIOCGSERIAL:
			return get_serial_info(info,
					       (struct serial_struct *) arg);
		case TIOCSSERIAL:
			return set_serial_info(info,
					       (struct serial_struct *) arg);
		case TIOCSERCONFIG:
			return do_autoconfig(info);

		case TIOCSERGETLSR: /* Get line status register */
			return get_lsr_info(info, (unsigned int *) arg);

		case TIOCSERGSTRUCT:
			if (copy_to_user((struct async_struct *) arg,
					 info, sizeof(struct async_struct)))
				return -EFAULT;
			return 0;
				
		/*
		 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)to change
		 * - mask passed in arg for lines of interest
 		 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
		 * Caller should use TIOCGICOUNT to see which one it was
		 */
		case TIOCMIWAIT:
			save_flags(flags); cli();
			/* note the counters on entry */
			cprev = info->state->icount;
			restore_flags(flags);
			while (1) {
				interruptible_sleep_on(&info->delta_msr_wait);
				/* see if a signal did it */
				if (signal_pending(current))
					return -ERESTARTSYS;
				save_flags(flags); cli(); 
				cnow = info->state->icount; /* atomic copy */
				restore_flags(flags); 
				if (cnow.rng == cprev.rng && 
				    cnow.dsr == cprev.dsr && 
				    cnow.dcd == cprev.dcd && 
				    cnow.cts == cprev.cts)
					return -EIO; /* no change => error */
				if ( ((arg & TIOCM_RNG) && 
				      (cnow.rng != cprev.rng)) ||
				     ((arg & TIOCM_DSR) && 
				      (cnow.dsr != cprev.dsr)) ||
				     ((arg & TIOCM_CD)  && 
				      (cnow.dcd != cprev.dcd)) ||
				     ((arg & TIOCM_CTS) && 
				      (cnow.cts != cprev.cts)) ) {
					return 0;
				}
				cprev = cnow;
			}
			/* NOTREACHED */

		/* 
		 * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
		 * Return: write counters to the user passed counter struct
		 * NB: both 1->0 and 0->1 transitions are counted except for
		 *     RI where only 0->1 is counted.
		 */
		case TIOCGICOUNT:
			save_flags(flags); cli(); 
			cnow = info->state->icount;
			restore_flags(flags);
			p_cuser = (struct serial_icounter_struct *) arg;
			error = put_user(cnow.cts, &p_cuser->cts);
			if (error) return error;
			error = put_user(cnow.dsr, &p_cuser->dsr);
			if (error) return error;
			error = put_user(cnow.rng, &p_cuser->rng);
			if (error) return error;
			error = put_user(cnow.dcd, &p_cuser->dcd);
			if (error) return error;
                        error = put_user(cnow.rx, &p_cuser->rx);
                        if (error) return error;
                        error = put_user(cnow.tx, &p_cuser->tx);
                        if (error) return error;
                        error = put_user(cnow.frame, &p_cuser->frame);
                        if (error) return error;
                        error = put_user(cnow.overrun, &p_cuser->overrun);
                        if (error) return error;
                        error = put_user(cnow.parity, &p_cuser->parity);
                        if (error) return error;
                        error = put_user(cnow.brk, &p_cuser->brk);
                        if (error) return error;
                        error = put_user(cnow.buf_overrun, &p_cuser->buf_overrun);

			if (error) return error;
			return 0;

                case TIOCSERGWILD:
                case TIOCSERSWILD:
                       /* "setserial -W" is called in Debian boot */
                        printk ("TIOCSER?WILD ioctl obsolete, ignored.\n");
                        return 0;
 
		default:
			return -ENOIOCTLCMD;
		}
	return 0;
}

static void rs_set_termios(struct tty_struct *tty, struct termios *old_termios)
{
	struct async_struct *info = (struct async_struct *)tty->driver_data;
	unsigned int cflag = tty->termios->c_cflag;

	if (   (cflag == old_termios->c_cflag)
	    && (   RELEVANT_IFLAG(tty->termios->c_iflag) 
		== RELEVANT_IFLAG(old_termios->c_iflag)))
	  return;

	change_speed(info);

	/* Handle turning off CRTSCTS */
	if ((old_termios->c_cflag & CRTSCTS) &&
	    !(cflag & CRTSCTS)) {
		tty->hw_stopped = 0;
		rs_start(tty);
	}

}

/*
 * ------------------------------------------------------------
 * rs_close()
 * 
 * This routine is called when the serial port gets closed.  First, we
 * wait for the last remaining data to be sent.  Then, we unlink its
 * async structure from the interrupt chain if necessary, and we free
 * that IRQ if nothing is left in the chain.
 * ------------------------------------------------------------
 */
static void rs_close(struct tty_struct *tty, struct file * filp)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	struct serial_state *state;
	unsigned long flags;

	if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
		return;

	state = info->state;
	
	save_flags(flags); cli();
	
	if (tty_hung_up_p(filp)) {
		DBG_CNT("before DEC-hung");
		MOD_DEC_USE_COUNT;
		restore_flags(flags);
		return;
	}
	
#ifdef SERIAL_DEBUG_OPEN
	baget_printk("rs_close ttys%d, count = %d\n", 
		     info->line, state->count);
#endif
	if ((tty->count == 1) && (state->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  state->count should always
		 * be one in these conditions.  If it's greater than
		 * one, we've got real problems, since it means the
		 * serial port won't be shutdown.
		 */
		baget_printk("rs_close: bad serial port count; "
			     "tty->count is 1, "
			     "state->count is %d\n", state->count);
		state->count = 1;
	}
	if (--state->count < 0) {
		baget_printk("rs_close: bad serial port count for "
			     "ttys%d: %d\n",
			     info->line, state->count);
		state->count = 0;
	}
	if (state->count) {
		DBG_CNT("before DEC-2");
		MOD_DEC_USE_COUNT;
		restore_flags(flags);
		return;
	}
	info->flags |= ASYNC_CLOSING;
	/*
	 * Save the termios structure, since this port may have
	 * separate termios for callout and dialin.
	 */
	if (info->flags & ASYNC_NORMAL_ACTIVE)
		info->state->normal_termios = *tty->termios;
	if (info->flags & ASYNC_CALLOUT_ACTIVE)
		info->state->callout_termios = *tty->termios;
	/*
	 * Now we wait for the transmit buffer to clear; and we notify 
	 * the line discipline to only process XON/XOFF characters.
	 */
	tty->closing = 1;
	if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE)
		tty_wait_until_sent(tty, info->closing_wait);
	/*
	 * At this point we stop accepting input.  To do this, we
	 * disable the receive line status interrupts, and tell the
	 * interrupt driver to stop checking the data ready bit in the
	 * line status register.
	 */
	info->IER &= ~(VAC_UART_INT_RX_BREAK_CHANGE | VAC_UART_INT_RX_ERRS);
	info->read_status_mask &= ~VAC_UART_STATUS_RX_READY;
	if (info->flags & ASYNC_INITIALIZED) {
		serial_outw(info, VAC_UART_INT_MASK, info->IER);
		/*
		 * Before we drop DTR, make sure the UART transmitter
		 * has completely drained; this is especially
		 * important if there is a transmit FIFO!
		 */
		rs_wait_until_sent(tty, info->timeout);
	}
	shutdown(info);
	if (tty->driver.flush_buffer)
		tty->driver.flush_buffer(tty);
	if (tty->ldisc.flush_buffer)
		tty->ldisc.flush_buffer(tty);
	tty->closing = 0;
	info->event = 0;
	info->tty = 0;
	if (info->blocked_open) {
		if (info->close_delay) {
			current->state = TASK_INTERRUPTIBLE;
			schedule_timeout(info->close_delay);
		}
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
			 ASYNC_CLOSING);
	wake_up_interruptible(&info->close_wait);
	MOD_DEC_USE_COUNT;
	restore_flags(flags);
}

/*
 * rs_wait_until_sent() --- wait until the transmitter is empty
 */
static void rs_wait_until_sent(struct tty_struct *tty, int timeout)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	unsigned long orig_jiffies, char_time;
	int lsr;
	
	if (serial_paranoia_check(info, tty->device, "rs_wait_until_sent"))
		return;

	if (info->state->type == PORT_UNKNOWN)
		return;

        if (info->xmit_fifo_size == 0)
                return; /* Just in case.... */

	orig_jiffies = jiffies;
	/*
	 * Set the check interval to be 1/5 of the estimated time to
	 * send a single character, and make it at least 1.  The check
	 * interval should also be less than the timeout.
	 * 
	 * Note: we have to use pretty tight timings here to satisfy
	 * the NIST-PCTS.
	 */
	char_time = (info->timeout - HZ/50) / info->xmit_fifo_size;
	char_time = char_time / 5;
	if (char_time == 0)
		char_time = 1;
	if (timeout)
	  char_time = MIN(char_time, timeout);
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
	baget_printk("In rs_wait_until_sent(%d) check=%lu...", 
		     timeout, char_time);
	baget_printk("jiff=%lu...", jiffies);
#endif
	while (!((lsr = serial_inp(info, VAC_UART_INT_STATUS)) & \
		 VAC_UART_STATUS_TX_EMPTY)) {
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
		baget_printk("lsr = %d (jiff=%lu)...", lsr, jiffies);
#endif
		current->state = TASK_INTERRUPTIBLE;
		schedule_timeout(char_time);
		if (signal_pending(current))
			break;
		if (timeout && ((orig_jiffies + timeout) < jiffies))
			break;
	}
	current->state = TASK_RUNNING;
#ifdef SERIAL_DEBUG_RS_WAIT_UNTIL_SENT
	baget_printk("lsr = %d (jiff=%lu)...done\n", lsr, jiffies);
#endif
}

/*
 * rs_hangup() --- called by tty_hangup() when a hangup is signaled.
 */
static void rs_hangup(struct tty_struct *tty)
{
	struct async_struct * info = (struct async_struct *)tty->driver_data;
	struct serial_state *state = info->state;
	
	if (serial_paranoia_check(info, tty->device, "rs_hangup"))
		return;

	state = info->state;
	
	rs_flush_buffer(tty);
	shutdown(info);
	info->event = 0;
	state->count = 0;
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE);
	info->tty = 0;
	wake_up_interruptible(&info->open_wait);
}

/*
 * ------------------------------------------------------------
 * rs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct async_struct *info)
{
	DECLARE_WAITQUEUE(wait, current);
	struct serial_state *state = info->state;
	int		retval;
	int		do_clocal = 0,  extra_count = 0;  
	unsigned long   flags; 

	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (tty_hung_up_p(filp) ||
	    (info->flags & ASYNC_CLOSING)) {
		if (info->flags & ASYNC_CLOSING)
			interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
		return ((info->flags & ASYNC_HUP_NOTIFY) ?
			-EAGAIN : -ERESTARTSYS);
#else
		return -EAGAIN;
#endif
	}

	/*
	 * If this is a callout device, then just make sure the normal
	 * device isn't being used.
	 */
	if (tty->driver.subtype == SERIAL_TYPE_CALLOUT) {
		if (info->flags & ASYNC_NORMAL_ACTIVE)
			return -EBUSY;
		if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (info->flags & ASYNC_SESSION_LOCKOUT) &&
		    (info->session != current->session))
		    return -EBUSY;
		if ((info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (info->flags & ASYNC_PGRP_LOCKOUT) &&
		    (info->pgrp != current->pgrp))
		    return -EBUSY;
		info->flags |= ASYNC_CALLOUT_ACTIVE;
		return 0;
	}
	
	/*
	 * If non-blocking mode is set, or the port is not enabled,
	 * then make the check up front and then exit.
	 */
	if ((filp->f_flags & O_NONBLOCK) ||
	    (tty->flags & (1 << TTY_IO_ERROR))) {
		if (info->flags & ASYNC_CALLOUT_ACTIVE)
			return -EBUSY;
		info->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	if (info->flags & ASYNC_CALLOUT_ACTIVE) {
		if (state->normal_termios.c_cflag & CLOCAL)
			do_clocal = 1;
	} else {
		if (tty->termios->c_cflag & CLOCAL)
			do_clocal = 1;
	}
	
	/*
	 * Block waiting for the carrier detect and the line to become
	 * free (i.e., not in use by the callout).  While we are in
	 * this loop, state->count is dropped by one, so that
	 * rs_close() knows when to free things.  We restore it upon
	 * exit, either normal or abnormal.
	 */
	retval = 0;
	add_wait_queue(&info->open_wait, &wait);
#ifdef SERIAL_DEBUG_OPEN
	baget_printk("block_til_ready before block: ttys%d, count = %d\n",
	       state->line, state->count);
#endif
	save_flags(flags); cli(); 
	if (!tty_hung_up_p(filp)) {
		extra_count = 1; 
		state->count--;
	}
	restore_flags(flags); 
	info->blocked_open++;
	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) ||
		    !(info->flags & ASYNC_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
			if (info->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;	
#else
			retval = -EAGAIN;
#endif
			break;
		}
		if (!(info->flags & ASYNC_CALLOUT_ACTIVE) &&
		    !(info->flags & ASYNC_CLOSING))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
#ifdef SERIAL_DEBUG_OPEN
		baget_printk("block_til_ready blocking: ttys%d, count = %d\n",
		       info->line, state->count);
#endif
		schedule();
	}
	current->state = TASK_RUNNING;
	remove_wait_queue(&info->open_wait, &wait);
	if (extra_count)
		state->count++;
	info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
	baget_printk("block_til_ready after blocking: ttys%d, count = %d\n",
	       info->line, state->count);