コード例 #1
0
int gs_block_til_ready(void *port_, struct file * filp)
{
	struct gs_port *gp = port_;
	struct tty_port *port = &gp->port;
	DECLARE_WAITQUEUE(wait, current);
	int    retval;
	int    do_clocal = 0;
	int    CD;
	struct tty_struct *tty;
	unsigned long flags;

	func_enter ();

	if (!port) return 0;

	tty = port->tty;

	gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n"); 
	/*
	 * 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) || port->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&port->close_wait);
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	gs_dprintk (GS_DEBUG_BTR, "after hung up\n"); 

	/*
	 * 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))) {
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	gs_dprintk (GS_DEBUG_BTR, "after nonblock\n"); 
 
	if (C_CLOCAL(tty))
		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, port->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(&port->open_wait, &wait);

	gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n"); 
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp)) {
		port->count--;
	}
	port->blocked_open++;
	spin_unlock_irqrestore(&port->lock, flags);
	while (1) {
		CD = tty_port_carrier_raised(port);
		gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
		set_current_state (TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) ||
		    !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
			break;
		}
		if (!(port->flags & ASYNC_CLOSING) &&
		    (do_clocal || CD))
			break;
		gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n", 
		(int)signal_pending (current), *(long*)(&current->blocked)); 
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
		    port->blocked_open);
	set_current_state (TASK_RUNNING);
	remove_wait_queue(&port->open_wait, &wait);
	
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp)) {
		port->count++;
	}
	port->blocked_open--;
	if (retval == 0)
        	port->flags |= ASYNC_NORMAL_ACTIVE;
	spin_unlock_irqrestore(&port->lock, flags);
	func_exit ();
	return retval;
}			 
コード例 #2
0
void gs_close(struct tty_struct * tty, struct file * filp)
{
	unsigned long flags;
	struct gs_port *port;
	
	func_enter ();

	port = tty->driver_data;

	if (!port) return;

	if (!port->port.tty) {
		/* This seems to happen when this is called from vhangup. */
		gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->port.tty is NULL\n");
		port->port.tty = tty;
	}

	spin_lock_irqsave(&port->port.lock, flags);

	if (tty_hung_up_p(filp)) {
		spin_unlock_irqrestore(&port->port.lock, flags);
		if (port->rd->hungup)
			port->rd->hungup (port);
		func_exit ();
		return;
	}

	if ((tty->count == 1) && (port->port.count != 1)) {
		printk(KERN_ERR "gs: gs_close port %p: bad port count;"
		       " tty->count is 1, port count is %d\n", port, port->port.count);
		port->port.count = 1;
	}
	if (--port->port.count < 0) {
		printk(KERN_ERR "gs: gs_close port %p: bad port count: %d\n", port, port->port.count);
		port->port.count = 0;
	}

	if (port->port.count) {
		gs_dprintk(GS_DEBUG_CLOSE, "gs_close port %p: count: %d\n", port, port->port.count);
		spin_unlock_irqrestore(&port->port.lock, flags);
		func_exit ();
		return;
	}
	port->port.flags |= ASYNC_CLOSING;

	/*
	 * 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 (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
	   tty_wait_until_sent(tty, port->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.
	 */

	spin_lock_irqsave(&port->driver_lock, flags);
	port->rd->disable_rx_interrupts (port);
	spin_unlock_irqrestore(&port->driver_lock, flags);
	spin_unlock_irqrestore(&port->port.lock, flags);

	/* close has no way of returning "EINTR", so discard return value */
	if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
		gs_wait_tx_flushed (port, port->closing_wait);

	port->port.flags &= ~GS_ACTIVE;

	gs_flush_buffer(tty);

	tty_ldisc_flush(tty);
	tty->closing = 0;

	spin_lock_irqsave(&port->driver_lock, flags);
	port->event = 0;
	port->rd->close (port);
	port->rd->shutdown_port (port);
	spin_unlock_irqrestore(&port->driver_lock, flags);

	spin_lock_irqsave(&port->port.lock, flags);
	port->port.tty = NULL;

	if (port->port.blocked_open) {
		if (port->close_delay) {
			spin_unlock_irqrestore(&port->port.lock, flags);
			msleep_interruptible(jiffies_to_msecs(port->close_delay));
			spin_lock_irqsave(&port->port.lock, flags);
		}
		wake_up_interruptible(&port->port.open_wait);
	}
	port->port.flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING | ASYNC_INITIALIZED);
	spin_unlock_irqrestore(&port->port.lock, flags);
	wake_up_interruptible(&port->port.close_wait);

	func_exit ();
}
コード例 #3
0
/*
 * ------------------------------------------------------------
 * rs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct cnxt_serial *info)
{
	DECLARE_WAITQUEUE(wait, current);
	int		retval;
	int		do_clocal = 0;

	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (info->flags & S_CLOSING) {
		interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
		if (info->flags & S_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -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 & S_NORMAL_ACTIVE)
			return -EBUSY;
		if ((info->flags & S_CALLOUT_ACTIVE) &&
		    (info->flags & S_SESSION_LOCKOUT) &&
		    (info->session != current->session))
		    return -EBUSY;
		if ((info->flags & S_CALLOUT_ACTIVE) &&
		    (info->flags & S_PGRP_LOCKOUT) &&
		    (info->pgrp != current->pgrp))
		    return -EBUSY;
		info->flags |= S_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 & S_CALLOUT_ACTIVE)
			return -EBUSY;
		info->flags |= S_NORMAL_ACTIVE;
		return 0;
	}

	if (info->flags & S_CALLOUT_ACTIVE) {
		if (info->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, info->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);

	info->count--;
	info->blocked_open++;
	while (1) {
		cli();
		if (!(info->flags & S_CALLOUT_ACTIVE))
		  //m68k_rtsdtr(info, 1);
		
		sti();
		current->state = TASK_INTERRUPTIBLE;
		if (tty_hung_up_p(filp) ||
		    !(info->flags & S_INITIALIZED)) {
#ifdef SERIAL_DO_RESTART
			if (info->flags & S_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;	
#else
			retval = -EAGAIN;
#endif
			break;
		}
		if (!(info->flags & S_CALLOUT_ACTIVE) &&
		    !(info->flags & S_CLOSING) && do_clocal)
			break;
                if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	current->state = TASK_RUNNING;
	remove_wait_queue(&info->open_wait, &wait);
	if (!tty_hung_up_p(filp))
		info->count++;
	info->blocked_open--;

	if (retval)
		return retval;
	info->flags |= S_NORMAL_ACTIVE;
	return 0;
}	
コード例 #4
0
ファイル: tty_port.c プロジェクト: 7799/linux
int tty_port_block_til_ready(struct tty_port *port,
				struct tty_struct *tty, struct file *filp)
{
	int do_clocal = 0, retval;
	unsigned long flags;
	DEFINE_WAIT(wait);

	/* block if port is in the process of being closed */
	if (tty_hung_up_p(filp) || port->flags & ASYNC_CLOSING) {
		wait_event_interruptible_tty(tty, port->close_wait,
				!(port->flags & ASYNC_CLOSING));
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	/* if non-blocking mode is set we can pass directly to open unless
	   the port has just hung up or is in another error state */
	if (tty->flags & (1 << TTY_IO_ERROR)) {
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}
	if (filp->f_flags & O_NONBLOCK) {
		/* Indicate we are open */
		if (tty->termios.c_cflag & CBAUD)
			tty_port_raise_dtr_rts(port);
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	if (C_CLOCAL(tty))
		do_clocal = 1;

	/* Block waiting until we can proceed. We may need to wait for the
	   carrier, but we must also wait for any close that is in progress
	   before the next open may complete */

	retval = 0;

	/* The port lock protects the port counts */
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp))
		port->count--;
	port->blocked_open++;
	spin_unlock_irqrestore(&port->lock, flags);

	while (1) {
		/* Indicate we are open */
		if (C_BAUD(tty) && test_bit(ASYNCB_INITIALIZED, &port->flags))
			tty_port_raise_dtr_rts(port);

		prepare_to_wait(&port->open_wait, &wait, TASK_INTERRUPTIBLE);
		/* Check for a hangup or uninitialised port.
							Return accordingly */
		if (tty_hung_up_p(filp) || !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
			break;
		}
		/*
		 * Probe the carrier. For devices with no carrier detect
		 * tty_port_carrier_raised will always return true.
		 * Never ask drivers if CLOCAL is set, this causes troubles
		 * on some hardware.
		 */
		if (!(port->flags & ASYNC_CLOSING) &&
				(do_clocal || tty_port_carrier_raised(port)))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		tty_unlock(tty);
		schedule();
		tty_lock(tty);
	}
	finish_wait(&port->open_wait, &wait);

	/* Update counts. A parallel hangup will have set count to zero and
	   we must not mess that up further */
	spin_lock_irqsave(&port->lock, flags);
	if (!tty_hung_up_p(filp))
		port->count++;
	port->blocked_open--;
	if (retval == 0)
		port->flags |= ASYNC_NORMAL_ACTIVE;
	spin_unlock_irqrestore(&port->lock, flags);
	return retval;
}
コード例 #5
0
ファイル: n_hdlc.c プロジェクト: Anjali05/linux
/**
 * n_hdlc_tty_read - Called to retrieve one frame of data (if available)
 * @tty - pointer to tty instance data
 * @file - pointer to open file object
 * @buf - pointer to returned data buffer
 * @nr - size of returned data buffer
 * 	
 * Returns the number of bytes returned or error code.
 */
static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file,
			   __u8 __user *buf, size_t nr)
{
	struct n_hdlc *n_hdlc = tty2n_hdlc(tty);
	int ret = 0;
	struct n_hdlc_buf *rbuf;
	DECLARE_WAITQUEUE(wait, current);

	if (debuglevel >= DEBUG_LEVEL_INFO)	
		printk("%s(%d)n_hdlc_tty_read() called\n",__FILE__,__LINE__);
		
	/* Validate the pointers */
	if (!n_hdlc)
		return -EIO;

	/* verify user access to buffer */
	if (!access_ok(buf, nr)) {
		printk(KERN_WARNING "%s(%d) n_hdlc_tty_read() can't verify user "
		"buffer\n", __FILE__, __LINE__);
		return -EFAULT;
	}

	add_wait_queue(&tty->read_wait, &wait);

	for (;;) {
		if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
			ret = -EIO;
			break;
		}
		if (tty_hung_up_p(file))
			break;

		set_current_state(TASK_INTERRUPTIBLE);

		rbuf = n_hdlc_buf_get(&n_hdlc->rx_buf_list);
		if (rbuf) {
			if (rbuf->count > nr) {
				/* too large for caller's buffer */
				ret = -EOVERFLOW;
			} else {
				__set_current_state(TASK_RUNNING);
				if (copy_to_user(buf, rbuf->buf, rbuf->count))
					ret = -EFAULT;
				else
					ret = rbuf->count;
			}

			if (n_hdlc->rx_free_buf_list.count >
			    DEFAULT_RX_BUF_COUNT)
				kfree(rbuf);
			else
				n_hdlc_buf_put(&n_hdlc->rx_free_buf_list, rbuf);
			break;
		}
			
		/* no data */
		if (tty_io_nonblock(tty, file)) {
			ret = -EAGAIN;
			break;
		}

		schedule();

		if (signal_pending(current)) {
			ret = -EINTR;
			break;
		}
	}

	remove_wait_queue(&tty->read_wait, &wait);
	__set_current_state(TASK_RUNNING);

	return ret;
	
}	/* end of n_hdlc_tty_read() */
コード例 #6
0
ファイル: n_tty.c プロジェクト: mjduddin/B14CKB1RD_kernel_m8
static ssize_t n_tty_write(struct tty_struct *tty, struct file *file,
			   const unsigned char *buf, size_t nr)
{
	const unsigned char *b = buf;
	DECLARE_WAITQUEUE(wait, current);
	int c;
	ssize_t retval = 0;

	
	if (L_TOSTOP(tty) && file->f_op->write != redirected_tty_write) {
		retval = tty_check_change(tty);
		if (retval)
			return retval;
	}

	
	process_echoes(tty);

	add_wait_queue(&tty->write_wait, &wait);
	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		if (tty_hung_up_p(file) || (tty->link && !tty->link->count)) {
			retval = -EIO;
			break;
		}
		if (O_OPOST(tty) && !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) {
			while (nr > 0) {
				ssize_t num = process_output_block(tty, b, nr);
				if (num < 0) {
					if (num == -EAGAIN)
						break;
					retval = num;
					goto break_out;
				}
				b += num;
				nr -= num;
				if (nr == 0)
					break;
				c = *b;
				if (process_output(c, tty) < 0)
					break;
				b++; nr--;
			}
			if (tty->ops->flush_chars)
				tty->ops->flush_chars(tty);
		} else {
			while (nr > 0) {
				mutex_lock(&tty->output_lock);
				c = tty->ops->write(tty, b, nr);
				mutex_unlock(&tty->output_lock);
				if (c < 0) {
					retval = c;
					goto break_out;
				}
				if (!c)
					break;
				b += c;
				nr -= c;
			}
		}
		if (!nr)
			break;
		if (file->f_flags & O_NONBLOCK) {
			retval = -EAGAIN;
			break;
		}
		schedule();
	}
break_out:
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&tty->write_wait, &wait);
	if (b - buf != nr && tty->fasync)
		set_bit(TTY_DO_WRITE_WAKEUP, &tty->flags);
	return (b - buf) ? b - buf : retval;
}
コード例 #7
0
ファイル: simserial.c プロジェクト: BackupTheBerlios/arp2-svn
/*
 * This routine is called whenever a serial port is opened.  It
 * enables interrupts for a serial port, linking in its async structure into
 * the IRQ chain.   It also performs the serial-specific
 * initialization for the tty structure.
 */
static int rs_open(struct tty_struct *tty, struct file * filp)
{
	struct async_struct	*info;
	int			retval, line;
	unsigned long		page;

	line = tty->index;
	if ((line < 0) || (line >= NR_PORTS))
		return -ENODEV;
	retval = get_async_struct(line, &info);
	if (retval)
		return retval;
	tty->driver_data = info;
	info->tty = tty;

#ifdef SIMSERIAL_DEBUG
	printk("rs_open %s, count = %d\n", tty->name, info->state->count);
#endif
	info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

	if (!tmp_buf) {
		page = get_zeroed_page(GFP_KERNEL);
		if (!page)
			return -ENOMEM;
		if (tmp_buf)
			free_page(page);
		else
			tmp_buf = (unsigned char *) page;
	}

	/*
	 * If the port is the middle of closing, bail out now
	 */
	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
	}

	/*
	 * Start up serial port
	 */
	retval = startup(info);
	if (retval) {
		return retval;
	}

	/*
	 * figure out which console to use (should be one already)
	 */
	console = console_drivers;
	while (console) {
		if ((console->flags & CON_ENABLED) && console->write) break;
		console = console->next;
	}

#ifdef SIMSERIAL_DEBUG
	printk("rs_open ttys%d successful\n", info->line);
#endif
	return 0;
}
コード例 #8
0
ファイル: 8253xsyn.c プロジェクト: archith/camera_project
int sab8253x_openS(struct tty_struct *tty, struct file * filp)
{
	struct sab_port	*port;
	int retval, line;
	int counter;
	unsigned long flags;
	
	MOD_INC_USE_COUNT;  
	line = MINOR(tty->device) - tty->driver.minor_start;
	
	for(counter = 0, port = AuraPortRoot; 
	    (counter < line) && (port != NULL); 
	    ++counter)
	{
		port = port->next;
	}
	
	if (!port) 
	{
		printk(KERN_ALERT "sab8253x_openS: can't find structure for line %d\n",
		       line);
		return -ENODEV;
	}
	
	save_flags(flags);		/* Need to protect port->tty element */
	cli();
	
	if(port->tty == 0)
	{
		port->tty = tty;
		tty->flip.tqueue.routine = sab8253x_flush_to_ldiscS;
	}
	tty->driver_data = port;
	
	if(port->function != FUNCTION_NR)
	{
		++(port->count);
		restore_flags(flags);
		return -ENODEV;		/* only allowed if there are no restrictions on the port */
	}
	
	if(port->open_type == OPEN_SYNC_NET)
	{
		port->tty = NULL;	/* Don't bother with open counting here
					   but make sure the tty field is NULL*/
		restore_flags(flags);
		return -EBUSY;
	}
	
	restore_flags(flags);
	
	if (sab8253x_serial_paranoia_check(port, tty->device, "sab8253x_openS"))
	{
		++(port->count);
		return -ENODEV;
	}
	
#ifdef DEBUG_OPEN
	printk("sab8253x_open %s%d, count = %d\n", tty->driver.name, port->line,
	       port->count);
#endif
	
	/*
	 * If the port is in the middle of closing, bail out now.
	 */
	if (tty_hung_up_p(filp) ||
	    (port->flags & FLAG8253X_CLOSING)) 
	{
		
		if (port->flags & FLAG8253X_CLOSING)
		{
			interruptible_sleep_on(&port->close_wait);
		}
#ifdef SERIAL_DO_RESTART
		++(port->count);
		return ((port->flags & FLAG8253X_HUP_NOTIFY) ?
			-EAGAIN : -ERESTARTSYS);
#else
		++(port->count);
		return -EAGAIN;
#endif
	}
	
	if(port->flags & FLAG8253X_NORMAL_ACTIVE)
	{
		if(port->open_type == OPEN_ASYNC)
		{
			++(port->count);
			return -EBUSY;	/* can't reopen in sync mode */
		}
	}
	if(port->open_type > OPEN_SYNC) /* can reopen a SYNC_TTY */
	{
		return -EBUSY;
	}
	if(Sab8253xSetUpLists(port))
	{
		++(port->count);
		return -ENODEV;
	}
	if(Sab8253xInitDescriptors2(port, sab8253xs_listsize, sab8253xs_rbufsize))
	{
		++(port->count);
		return -ENODEV;
	}
	
	retval = sab8253x_startupS(port);
	if (retval)
	{
		++(port->count);
		return retval;		/* does not check channel mode */
	}
	
	retval = sab8253x_block_til_ready(tty, filp, port); /* checks channel mode */
	++(port->count);
	if (retval) 
	{
		return retval;
	}
	
	port->tty = tty;		/* may change here once through the block */
	/* because now the port belongs to an new tty */
	tty->flip.tqueue.routine = sab8253x_flush_to_ldiscS;
	if(Sab8253xSetUpLists(port))
	{
		return -ENODEV;
	}
	if(Sab8253xInitDescriptors2(port, sab8253xs_listsize, sab8253xs_rbufsize))
	{
		Sab8253xCleanUpTransceiveN(port);	/* the network functions should be okay -- only difference */
		/* is the crc32 that is appended */
		return -ENODEV;
	}
	
	/*
	 * Start up serial port
	 */
	retval = sab8253x_startupS(port); /* in case cu was running the first time
					   * the function was called*/
	if (retval)
	{
		return retval;		/* does not check channel mode */
	}
	
	if ((port->count == 1) &&
	    (port->flags & FLAG8253X_SPLIT_TERMIOS)) 
	{
		if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
		{
			*tty->termios = port->normal_termios;
		}
		else 
		{
			*tty->termios = port->callout_termios;
		}
		sab8253x_change_speedS(port);
	}
	
	
#ifdef XCONFIG_SERIAL_CONSOLE
	if (sab8253x_console.cflag && sab8253x_console.index == line) 
	{
		tty->termios->c_cflag = sab8253x_console.cflag;
		sab8253x_console.cflag = 0;
		change_speed(port);
	}
#endif
	
	port->session = current->session;
	port->pgrp = current->pgrp;
	port->open_type = OPEN_SYNC;
	return 0;
}
コード例 #9
0
ファイル: ipw.c プロジェクト: ClarkChen633/rtl819x-toolchain
static void ipw_close(struct tty_struct *tty,
			struct usb_serial_port *port, struct file *filp)
{
	struct usb_device *dev = port->serial->dev;
	int result;

	if (tty_hung_up_p(filp)) {
		dbg("%s: tty_hung_up_p ...", __func__);
		return;
	}

	/*--1: drop the dtr */
	dbg("%s:dropping dtr", __func__);
	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			 IPW_SIO_SET_PIN,
			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
			 IPW_PIN_CLRDTR,
			 0,
			 NULL,
			 0,
			 200000);
	if (result < 0)
		dev_err(&port->dev, "dropping dtr failed (error = %d)\n",
								result);

	/*--2: drop the rts */
	dbg("%s:dropping rts", __func__);
	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			 IPW_SIO_SET_PIN, USB_TYPE_VENDOR |
			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
			 IPW_PIN_CLRRTS,
			 0,
			 NULL,
			 0,
			 200000);
	if (result < 0)
		dev_err(&port->dev,
				"dropping rts failed (error = %d)\n", result);


	/*--3: purge */
	dbg("%s:sending purge", __func__);
	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			 IPW_SIO_PURGE, USB_TYPE_VENDOR |
			 		USB_RECIP_INTERFACE | USB_DIR_OUT,
			 0x03,
			 0,
			 NULL,
			 0,
			 200000);
	if (result < 0)
		dev_err(&port->dev, "purge failed (error = %d)\n", result);


	/* send RXBULK_off (tell modem to stop transmitting bulk data on
	   rx chan) */
	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			 IPW_SIO_RXCTL,
			 USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
			 IPW_RXBULK_OFF,
			 0, /* index */
			 NULL,
			 0,
			 100000);

	if (result < 0)
		dev_err(&port->dev,
			"Disabling bulk RxRead failed (error = %d)\n", result);

	/* shutdown any in-flight urbs that we know about */
	usb_kill_urb(port->read_urb);
	usb_kill_urb(port->write_urb);
}
コード例 #10
0
ファイル: simserial.c プロジェクト: BackupTheBerlios/arp2-svn
/*
 * ------------------------------------------------------------
 * 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 ) return;

	state = info->state;

	local_irq_save(flags);
	if (tty_hung_up_p(filp)) {
#ifdef SIMSERIAL_DEBUG
		printk("rs_close: hung_up\n");
#endif
		local_irq_restore(flags);
		return;
	}
#ifdef SIMSERIAL_DEBUG
	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.
		 */
		printk(KERN_ERR "rs_close: bad serial port count; tty->count is 1, "
		       "state->count is %d\n", state->count);
		state->count = 1;
	}
	if (--state->count < 0) {
		printk(KERN_ERR "rs_close: bad serial port count for ttys%d: %d\n",
		       info->line, state->count);
		state->count = 0;
	}
	if (state->count) {
		local_irq_restore(flags);
		return;
	}
	info->flags |= ASYNC_CLOSING;
	local_irq_restore(flags);

	/*
	 * Now we wait for the transmit buffer to clear; and we notify
	 * the line discipline to only process XON/XOFF characters.
	 */
	shutdown(info);
	if (tty->driver->flush_buffer) tty->driver->flush_buffer(tty);
	if (tty->ldisc.flush_buffer) tty->ldisc.flush_buffer(tty);
	info->event = 0;
	info->tty = 0;
	if (info->blocked_open) {
		if (info->close_delay)
			schedule_timeout_interruptible(info->close_delay);
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&info->close_wait);
}
コード例 #11
0
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct async_struct *info)
{
#ifdef DECLARE_WAITQUEUE
	DECLARE_WAITQUEUE(wait, current);
#else
	struct wait_queue wait = { current, NULL };
#endif
	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 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))) {
		info->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	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
	printk("block_til_ready before block: ttys%d, count = %d\n",
	       state->line, state->count);
#endif
	local_irq_save(flags);
	if (!tty_hung_up_p(filp)) {
		extra_count = 1;
		state->count--;
	}
	local_irq_restore(flags);
	info->blocked_open++;
	while (1) {
		local_irq_save(flags);
		if (tty->termios->c_cflag & CBAUD)
		        rtsdtr_ctrl(SER_DTR|SER_RTS);
		local_irq_restore(flags);
		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_CLOSING) &&
		    (do_clocal || (!(ciab.pra & SER_DCD)) ))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
#ifdef SERIAL_DEBUG_OPEN
		printk("block_til_ready blocking: ttys%d, count = %d\n",
		       info->line, state->count);
#endif
		schedule();
	}
	__set_current_state(TASK_RUNNING);
	remove_wait_queue(&info->open_wait, &wait);
	if (extra_count)
		state->count++;
	info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
	printk("block_til_ready after blocking: ttys%d, count = %d\n",
	       info->line, state->count);
#endif
	if (retval)
		return retval;
	info->flags |= ASYNC_NORMAL_ACTIVE;
	return 0;
}
コード例 #12
0
static void rs_close(struct tty_struct *tty, struct file * filp)
{
	struct async_struct * info = tty->driver_data;
	struct serial_state *state;
	unsigned long flags;

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

	state = info->state;

	local_irq_save(flags);

	if (tty_hung_up_p(filp)) {
		DBG_CNT("before DEC-hung");
		local_irq_restore(flags);
		return;
	}

#ifdef SERIAL_DEBUG_OPEN
	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.
		 */
		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) {
		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");
		local_irq_restore(flags);
		return;
	}
	info->flags |= ASYNC_CLOSING;
	/*
	 * 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->read_status_mask &= ~UART_LSR_DR;
	if (info->flags & ASYNC_INITIALIZED) {
	        /* disable receive interrupts */
	        custom.intena = IF_RBF;
		mb();
		/* clear any pending receive interrupt */
		custom.intreq = IF_RBF;
		mb();

		/*
		 * 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);
	rs_flush_buffer(tty);
		
	tty_ldisc_flush(tty);
	tty->closing = 0;
	info->event = 0;
	info->tty = NULL;
	if (info->blocked_open) {
		if (info->close_delay) {
			msleep_interruptible(jiffies_to_msecs(info->close_delay));
		}
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&info->close_wait);
	local_irq_restore(flags);
}
コード例 #13
0
static void rs_close(struct tty_struct *tty, struct file * filp)
{
	struct cnxt_serial * info = (struct cnxt_serial *)tty->driver_data;
	unsigned long flags;

	if (!info || serial_paranoia_check(info, tty->device, "rs_close"))
		return;
	
	save_flags(flags); cli();
	
	if (tty_hung_up_p(filp)) {
		restore_flags(flags);
		return;
	}
	
	if ((tty->count == 1) && (info->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  info->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.
		 */
		printk("rs_close: bad serial port count; tty->count is 1, "
		       "info->count is %d\n", info->count);
		info->count = 1;
	}
	if (--info->count < 0) {
		printk("rs_close: bad serial port count for ttyS%d: %d\n",
		       info->line, info->count);
		info->count = 0;
	}
	if (info->count) {
		restore_flags(flags);
		return;
	}
	// closing port so disable interrupts
	//set_ints_mode(0);
	info->use_ints = 0;

	info->flags |= S_CLOSING;
	/*
	 * Save the termios structure, since this port may have
	 * separate termios for callout and dialin.
	 */
	if (info->flags & S_NORMAL_ACTIVE)
		info->normal_termios = *tty->termios;
	if (info->flags & S_CALLOUT_ACTIVE)
		info->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 != S_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.
	 */

	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 (tty->ldisc.num != tty_ldiscs[N_TTY].num) {
		if (tty->ldisc.close)
			(tty->ldisc.close)(tty);
		tty->ldisc = tty_ldiscs[N_TTY];
		tty->termios->c_line = N_TTY;
		if (tty->ldisc.open)
			(tty->ldisc.open)(tty);
	}
	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 &= ~(S_NORMAL_ACTIVE|S_CALLOUT_ACTIVE|
			 S_CLOSING);
	wake_up_interruptible(&info->close_wait);
	restore_flags(flags);
}
コード例 #14
0
/*
 * ------------------------------------------------------------
 * mcfrs_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
 * S structure from the interrupt chain if necessary, and we free
 * that IRQ if nothing is left in the chain.
 * ------------------------------------------------------------
 */
static void mcfrs_close(struct tty_struct *tty, struct file * filp)
{
	volatile unsigned char	*uartp;
	struct mcf_serial	*info = (struct mcf_serial *)tty->driver_data;
	unsigned long		flags;

	if (!info || serial_paranoia_check(info, tty->name, "mcfrs_close"))
		return;
	
	local_irq_save(flags);
	
	if (tty_hung_up_p(filp)) {
		local_irq_restore(flags);
		return;
	}
	
#ifdef SERIAL_DEBUG_OPEN
	printk("mcfrs_close ttyS%d, count = %d\n", info->line, info->count);
#endif
	if ((tty->count == 1) && (info->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  Info->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.
		 */
		printk("MCFRS: bad serial port count; tty->count is 1, "
		       "info->count is %d\n", info->count);
		info->count = 1;
	}
	if (--info->count < 0) {
		printk("MCFRS: bad serial port count for ttyS%d: %d\n",
		       info->line, info->count);
		info->count = 0;
	}
	if (info->count) {
		local_irq_restore(flags);
		return;
	}
	info->flags |= ASYNC_CLOSING;

	/*
	 * 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->imr &= ~MCFUART_UIR_RXREADY;
	uartp = info->addr;
	uartp[MCFUART_UIMR] = info->imr;

#if 0
	/* FIXME: do we need to keep this enabled for console?? */
	if (mcfrs_console_inited && (mcfrs_console_port == info->line)) {
		/* Do not disable the UART */ ;
	} else
#endif
	shutdown(info);
	if (tty->driver->flush_buffer)
		tty->driver->flush_buffer(tty);
	tty_ldisc_flush(tty);
	
	tty->closing = 0;
	info->event = 0;
	info->tty = 0;
#if 0	
	if (tty->ldisc.num != ldiscs[N_TTY].num) {
		if (tty->ldisc.close)
			(tty->ldisc.close)(tty);
		tty->ldisc = ldiscs[N_TTY];
		tty->termios->c_line = N_TTY;
		if (tty->ldisc.open)
			(tty->ldisc.open)(tty);
	}
#endif	
	if (info->blocked_open) {
		if (info->close_delay) {
			msleep_interruptible(jiffies_to_msecs(info->close_delay));
		}
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&info->close_wait);
	local_irq_restore(flags);
}
コード例 #15
0
ファイル: 68328serial.c プロジェクト: kprog/linux
/*
 * ------------------------------------------------------------
 * 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
 * S 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 m68k_serial * info = (struct m68k_serial *)tty->driver_data;
	m68328_uart *uart = &uart_addr[info->line];
	unsigned long flags;

	if (!info || serial_paranoia_check(info, tty->name, "rs_close"))
		return;
	
	local_irq_save(flags);
	
	if (tty_hung_up_p(filp)) {
		local_irq_restore(flags);
		return;
	}
	
	if ((tty->count == 1) && (info->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  Info->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.
		 */
		printk("rs_close: bad serial port count; tty->count is 1, "
		       "info->count is %d\n", info->count);
		info->count = 1;
	}
	if (--info->count < 0) {
		printk("rs_close: bad serial port count for ttyS%d: %d\n",
		       info->line, info->count);
		info->count = 0;
	}
	if (info->count) {
		local_irq_restore(flags);
		return;
	}
	info->flags |= S_CLOSING;
	/*
	 * 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 != S_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.
	 */

	uart->ustcnt &= ~USTCNT_RXEN;
	uart->ustcnt &= ~(USTCNT_RXEN | USTCNT_RX_INTR_MASK);

	shutdown(info);
	rs_flush_buffer(tty);
		
	tty_ldisc_flush(tty);
	tty->closing = 0;
	info->event = 0;
	info->tty = NULL;
#warning "This is not and has never been valid so fix it"	
#if 0
	if (tty->ldisc.num != ldiscs[N_TTY].num) {
		if (tty->ldisc.close)
			(tty->ldisc.close)(tty);
		tty->ldisc = ldiscs[N_TTY];
		tty->termios->c_line = N_TTY;
		if (tty->ldisc.open)
			(tty->ldisc.open)(tty);
	}
#endif	
	if (info->blocked_open) {
		if (info->close_delay) {
			msleep_interruptible(jiffies_to_msecs(info->close_delay));
		}
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(S_NORMAL_ACTIVE|S_CLOSING);
	wake_up_interruptible(&info->close_wait);
	local_irq_restore(flags);
}
コード例 #16
0
/*
 * ------------------------------------------------------------
 * mcfrs_open() and friends
 * ------------------------------------------------------------
 */
static int block_til_ready(struct tty_struct *tty, struct file * filp,
			   struct mcf_serial *info)
{
	DECLARE_WAITQUEUE(wait, current);
	int	retval;
	int	do_clocal = 0;

	/*
	 * If the device is in the middle of being closed, then block
	 * until it's done, and then try again.
	 */
	if (info->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&info->close_wait);
#ifdef SERIAL_DO_RESTART
		if (info->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
#else
		return -EAGAIN;
#endif
	}
	
	/*
	 * 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))) {
		info->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	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, info->count is dropped by one, so that
	 * mcfrs_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
	printk("block_til_ready before block: ttyS%d, count = %d\n",
	       info->line, info->count);
#endif
	info->count--;
	info->blocked_open++;
	while (1) {
		local_irq_disable();
		mcfrs_setsignals(info, 1, 1);
		local_irq_enable();
		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_CLOSING) &&
		    (do_clocal || (mcfrs_getsignals(info) & TIOCM_CD)))
			break;
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
#ifdef SERIAL_DEBUG_OPEN
		printk("block_til_ready blocking: ttyS%d, count = %d\n",
		       info->line, info->count);
#endif
		schedule();
	}
	current->state = TASK_RUNNING;
	remove_wait_queue(&info->open_wait, &wait);
	if (!tty_hung_up_p(filp))
		info->count++;
	info->blocked_open--;
#ifdef SERIAL_DEBUG_OPEN
	printk("block_til_ready after blocking: ttyS%d, count = %d\n",
	       info->line, info->count);
#endif
	if (retval)
		return retval;
	info->flags |= ASYNC_NORMAL_ACTIVE;
	return 0;
}	
コード例 #17
0
ファイル: n_tty.c プロジェクト: 8l/fbui
static ssize_t read_chan(struct tty_struct *tty, struct file *file,
			 unsigned char __user *buf, size_t nr)
{
	unsigned char __user *b = buf;
	DECLARE_WAITQUEUE(wait, current);
	int c;
	int minimum, time;
	ssize_t retval = 0;
	ssize_t size;
	long timeout;
	unsigned long flags;

do_it_again:

	if (!tty->read_buf) {
		printk("n_tty_read_chan: called with read_buf == NULL?!?\n");
		return -EIO;
	}

	c = job_control(tty, file);
	if(c < 0)
		return c;
	
	minimum = time = 0;
	timeout = MAX_SCHEDULE_TIMEOUT;
	if (!tty->icanon) {
		time = (HZ / 10) * TIME_CHAR(tty);
		minimum = MIN_CHAR(tty);
		if (minimum) {
			if (time)
				tty->minimum_to_wake = 1;
			else if (!waitqueue_active(&tty->read_wait) ||
				 (tty->minimum_to_wake > minimum))
				tty->minimum_to_wake = minimum;
		} else {
			timeout = 0;
			if (time) {
				timeout = time;
				time = 0;
			}
			tty->minimum_to_wake = minimum = 1;
		}
	}

	/*
	 *	Internal serialization of reads.
	 */
	if (file->f_flags & O_NONBLOCK) {
		if (down_trylock(&tty->atomic_read))
			return -EAGAIN;
	}
	else {
		if (down_interruptible(&tty->atomic_read))
			return -ERESTARTSYS;
	}

	add_wait_queue(&tty->read_wait, &wait);
	set_bit(TTY_DONT_FLIP, &tty->flags);
	while (nr) {
		/* First test for status change. */
		if (tty->packet && tty->link->ctrl_status) {
			unsigned char cs;
			if (b != buf)
				break;
			cs = tty->link->ctrl_status;
			tty->link->ctrl_status = 0;
			if (put_user(cs, b++)) {
				retval = -EFAULT;
				b--;
				break;
			}
			nr--;
			break;
		}
		/* This statement must be first before checking for input
		   so that any interrupt will set the state back to
		   TASK_RUNNING. */
		set_current_state(TASK_INTERRUPTIBLE);
		
		if (((minimum - (b - buf)) < tty->minimum_to_wake) &&
		    ((minimum - (b - buf)) >= 1))
			tty->minimum_to_wake = (minimum - (b - buf));
		
		if (!input_available_p(tty, 0)) {
			if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
				retval = -EIO;
				break;
			}
			if (tty_hung_up_p(file))
				break;
			if (!timeout)
				break;
			if (file->f_flags & O_NONBLOCK) {
				retval = -EAGAIN;
				break;
			}
			if (signal_pending(current)) {
				retval = -ERESTARTSYS;
				break;
			}
			clear_bit(TTY_DONT_FLIP, &tty->flags);
			timeout = schedule_timeout(timeout);
			set_bit(TTY_DONT_FLIP, &tty->flags);
			continue;
		}
		__set_current_state(TASK_RUNNING);

		/* Deal with packet mode. */
		if (tty->packet && b == buf) {
			if (put_user(TIOCPKT_DATA, b++)) {
				retval = -EFAULT;
				b--;
				break;
			}
			nr--;
		}

		if (tty->icanon) {
			/* N.B. avoid overrun if nr == 0 */
			while (nr && tty->read_cnt) {
 				int eol;

				eol = test_and_clear_bit(tty->read_tail,
						tty->read_flags);
				c = tty->read_buf[tty->read_tail];
				tty->read_buf[tty->read_tail] = 0; /* ZS */
				spin_lock_irqsave(&tty->read_lock, flags);
				tty->read_tail = ((tty->read_tail+1) &
						  (N_TTY_BUF_SIZE-1));
				tty->read_cnt--;
				if (eol) {
					/* this test should be redundant:
					 * we shouldn't be reading data if
					 * canon_data is 0
					 */
					if (--tty->canon_data < 0)
						tty->canon_data = 0;
				}
				spin_unlock_irqrestore(&tty->read_lock, flags);

				if (!eol || (c != __DISABLED_CHAR)) {
					if (put_user(c, b++)) {
						retval = -EFAULT;
						b--;
						break;
					}
					nr--;
				}
				if (eol)
					break;
			}
			if (retval)
				break;
		} else {
			int uncopied;
			uncopied = copy_from_read_buf(tty, &b, &nr);
			uncopied += copy_from_read_buf(tty, &b, &nr);
			if (uncopied) {
				retval = -EFAULT;
				break;
			}
		}

		/* If there is enough space in the read buffer now, let the
		 * low-level driver know. We use n_tty_chars_in_buffer() to
		 * check the buffer, as it now knows about canonical mode.
		 * Otherwise, if the driver is throttled and the line is
		 * longer than TTY_THRESHOLD_UNTHROTTLE in canonical mode,
		 * we won't get any more characters.
		 */
		if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE)
			check_unthrottle(tty);

		if (b - buf >= minimum)
			break;
		if (time)
			timeout = time;
	}
	clear_bit(TTY_DONT_FLIP, &tty->flags);
	up(&tty->atomic_read);
	remove_wait_queue(&tty->read_wait, &wait);

	if (!waitqueue_active(&tty->read_wait))
		tty->minimum_to_wake = minimum;

	__set_current_state(TASK_RUNNING);
	size = b - buf;
	if (size) {
		retval = size;
		if (nr)
	       		clear_bit(TTY_PUSH, &tty->flags);
	} else if (test_and_clear_bit(TTY_PUSH, &tty->flags))
		 goto do_it_again;

	return retval;
}
コード例 #18
0
ファイル: 8253xsyn.c プロジェクト: archith/camera_project
void sab8253x_closeS(struct tty_struct *tty, struct file * filp)
{
	struct sab_port *port = (struct sab_port *)tty->driver_data;
	unsigned long flags;
	
	MOD_DEC_USE_COUNT;	
	if (sab8253x_serial_paranoia_check(port, tty->device, "sab8253x_closeS"))
	{
		return;
	}

	if(port->open_type == OPEN_SYNC_NET)
	{				/* port->tty field should already be NULL */
		return;
	}
	
	save_flags(flags); cli();
	--(port->count);
	if (tty_hung_up_p(filp)) 
	{
		if(port->count == 0)	/* I think the reason for the weirdness
					   relates to freeing of structures in
					   the tty driver */
		{
			port->open_type = OPEN_NOT;
		}
		else if(port->count < 0)
		{
			printk(KERN_ALERT "XX20: port->count went negative.\n");
			port->count = 0;
			port->open_type = OPEN_NOT;
		}
		restore_flags(flags);
		return;
	}
	
#if 0
	if ((tty->count == 1) && (port->count != 0)) 
	{
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  port->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.
		 */
		printk("sab8253x_close: bad serial port count; tty->count is 1,"
		       " port->count is %d\n", port->count);
		port->count = 0;
	}
#endif
	
	if (port->count < 0) 
	{
		printk(KERN_ALERT "sab8253x_close: bad serial port count for ttys%d: %d\n",
		       port->line, port->count);
		port->count = 0;
	}
	if (port->count) 
	{
		restore_flags(flags);
		return;
	}
	port->flags |= FLAG8253X_CLOSING;
	
	/*
	 * Save the termios structure, since this port may have
	 * separate termios for callout and dialin.
	 */
	if (port->flags & FLAG8253X_NORMAL_ACTIVE)
	{
		port->normal_termios = *tty->termios;
	}
	if (port->flags & FLAG8253X_CALLOUT_ACTIVE)
	{
		port->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 (port->closing_wait != SAB8253X_CLOSING_WAIT_NONE) 
	{
		tty_wait_until_sent(tty, port->closing_wait);
	}
	
	/*
	 * At this point we stop accepting input.  To do this, we
	 * disable the receive line status interrupts, and turn off
	 * the receiver.
	 */
	
#if 0
	port->interrupt_mask0 |= SAB82532_IMR0_TCD; /* not needed for sync */
#endif
	WRITEB(port,imr0,port->interrupt_mask0);
	
	CLEAR_REG_BIT(port, mode, SAB82532_MODE_RAC); /* turn off receiver */
	
	if (port->flags & FLAG8253X_INITIALIZED) 
	{
		/*
		 * Before we drop DTR, make sure the UART transmitter
		 * has completely drained; this is especially
		 * important if there is a transmit FIFO!
		 */
		sab8253x_wait_until_sent(tty, port->timeout);
	}
	sab8253x_shutdownS(port);
	Sab8253xCleanUpTransceiveN(port);
	if (tty->driver.flush_buffer)
	{
		tty->driver.flush_buffer(tty);
	}
	if (tty->ldisc.flush_buffer)
	{
		tty->ldisc.flush_buffer(tty);
	}
	tty->closing = 0;
	port->event = 0;
	port->tty = 0;
	if (port->blocked_open) 
	{
		if (port->close_delay) 
		{
			current->state = TASK_INTERRUPTIBLE;
			schedule_timeout(port->close_delay);
		}
		wake_up_interruptible(&port->open_wait);
	}
	port->flags &= ~(FLAG8253X_NORMAL_ACTIVE|FLAG8253X_CALLOUT_ACTIVE|
			 FLAG8253X_CLOSING);
	wake_up_interruptible(&port->close_wait);
	port->open_type = OPEN_NOT;
	restore_flags(flags);
}
コード例 #19
0
int gs_block_til_ready(void *port_, struct file * filp)
{
	struct gs_port *port = port_;
	DECLARE_WAITQUEUE(wait, current);
	int    retval;
	int    do_clocal = 0;
	int    CD;
	struct tty_struct *tty;
	unsigned long flags;

	func_enter ();

	if (!port) return 0;

	tty = port->tty;

	if (!tty) return 0;

	gs_dprintk (GS_DEBUG_BTR, "Entering gs_block_till_ready.\n"); 
	/*
	 * 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) || port->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&port->close_wait);
		if (port->flags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	gs_dprintk (GS_DEBUG_BTR, "after hung up\n"); 

	/*
	 * If this is a callout device, then just make sure the normal
	 * device isn't being used.
	 */
	if (tty->driver.subtype == GS_TYPE_CALLOUT) {
		if (port->flags & ASYNC_NORMAL_ACTIVE)
			return -EBUSY;
		if ((port->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (port->flags & ASYNC_SESSION_LOCKOUT) &&
		    (port->session != current->session))
			return -EBUSY;
		if ((port->flags & ASYNC_CALLOUT_ACTIVE) &&
		    (port->flags & ASYNC_PGRP_LOCKOUT) &&
		    (port->pgrp != current->pgrp))
			return -EBUSY;
		port->flags |= ASYNC_CALLOUT_ACTIVE;
		return 0;
	}

	gs_dprintk (GS_DEBUG_BTR, "after subtype\n");

	/*
	 * 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 (port->flags & ASYNC_CALLOUT_ACTIVE)
			return -EBUSY;
		port->flags |= ASYNC_NORMAL_ACTIVE;
		return 0;
	}

	gs_dprintk (GS_DEBUG_BTR, "after nonblock\n"); 
 
	if (port->flags & ASYNC_CALLOUT_ACTIVE) {
		if (port->normal_termios.c_cflag & CLOCAL) 
			do_clocal = 1;
	} else {
		if (C_CLOCAL(tty))
			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, port->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(&port->open_wait, &wait);

	gs_dprintk (GS_DEBUG_BTR, "after add waitq.\n"); 
	save_flags(flags);
	cli();
	if (!tty_hung_up_p(filp))
		port->count--;
	restore_flags(flags);
	port->blocked_open++;
	while (1) {
		CD = port->rd->get_CD (port);
		gs_dprintk (GS_DEBUG_BTR, "CD is now %d.\n", CD);
		set_current_state (TASK_INTERRUPTIBLE);
		if (tty_hung_up_p(filp) ||
		    !(port->flags & ASYNC_INITIALIZED)) {
			if (port->flags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;
			break;
		}
		if (!(port->flags & ASYNC_CALLOUT_ACTIVE) &&
		    !(port->flags & ASYNC_CLOSING) &&
		    (do_clocal || CD))
			break;
		gs_dprintk (GS_DEBUG_BTR, "signal_pending is now: %d (%lx)\n", 
		(int)signal_pending (current), *(long*)(&current->blocked)); 
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		schedule();
	}
	gs_dprintk (GS_DEBUG_BTR, "Got out of the loop. (%d)\n",
		    port->blocked_open);
	set_current_state (TASK_RUNNING);
	remove_wait_queue(&port->open_wait, &wait);
	if (!tty_hung_up_p(filp))
		port->count++;
	port->blocked_open--;
	if (retval)
		return retval;

	port->flags |= ASYNC_NORMAL_ACTIVE;
	func_exit ();
	return 0;
}			 
コード例 #20
0
ファイル: n_tty.c プロジェクト: mjduddin/B14CKB1RD_kernel_m8
static ssize_t n_tty_read(struct tty_struct *tty, struct file *file,
			 unsigned char __user *buf, size_t nr)
{
	unsigned char __user *b = buf;
	DECLARE_WAITQUEUE(wait, current);
	int c;
	int minimum, time;
	ssize_t retval = 0;
	ssize_t size;
	long timeout;
	unsigned long flags;
	int packet;

do_it_again:

	if (WARN_ON(!tty->read_buf))
		return -EAGAIN;

	c = job_control(tty, file);
	if (c < 0)
		return c;

	minimum = time = 0;
	timeout = MAX_SCHEDULE_TIMEOUT;
	if (!tty->icanon) {
		time = (HZ / 10) * TIME_CHAR(tty);
		minimum = MIN_CHAR(tty);
		if (minimum) {
			if (time)
				tty->minimum_to_wake = 1;
			else if (!waitqueue_active(&tty->read_wait) ||
				 (tty->minimum_to_wake > minimum))
				tty->minimum_to_wake = minimum;
		} else {
			timeout = 0;
			if (time) {
				timeout = time;
				time = 0;
			}
			tty->minimum_to_wake = minimum = 1;
		}
	}

	if (file->f_flags & O_NONBLOCK) {
		if (!mutex_trylock(&tty->atomic_read_lock))
			return -EAGAIN;
	} else {
		if (mutex_lock_interruptible(&tty->atomic_read_lock))
			return -ERESTARTSYS;
	}
	packet = tty->packet;

	add_wait_queue(&tty->read_wait, &wait);
	while (nr) {
		
		if (packet && tty->link->ctrl_status) {
			unsigned char cs;
			if (b != buf)
				break;
			spin_lock_irqsave(&tty->link->ctrl_lock, flags);
			cs = tty->link->ctrl_status;
			tty->link->ctrl_status = 0;
			spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
			if (tty_put_user(tty, cs, b++)) {
				retval = -EFAULT;
				b--;
				break;
			}
			nr--;
			break;
		}
		set_current_state(TASK_INTERRUPTIBLE);

		if (((minimum - (b - buf)) < tty->minimum_to_wake) &&
		    ((minimum - (b - buf)) >= 1))
			tty->minimum_to_wake = (minimum - (b - buf));

		if (!input_available_p(tty, 0)) {
			if (test_bit(TTY_OTHER_CLOSED, &tty->flags)) {
				retval = -EIO;
				break;
			}
			if (tty_hung_up_p(file))
				break;
			if (!timeout)
				break;
			if (file->f_flags & O_NONBLOCK) {
				retval = -EAGAIN;
				break;
			}
			if (signal_pending(current)) {
				retval = -ERESTARTSYS;
				break;
			}
			n_tty_set_room(tty);
			timeout = schedule_timeout(timeout);
			BUG_ON(!tty->read_buf);
			continue;
		}
		__set_current_state(TASK_RUNNING);

		
		if (packet && b == buf) {
			if (tty_put_user(tty, TIOCPKT_DATA, b++)) {
				retval = -EFAULT;
				b--;
				break;
			}
			nr--;
		}

		if (tty->icanon && !L_EXTPROC(tty)) {
			
			while (nr && tty->read_cnt) {
				int eol;

				eol = test_and_clear_bit(tty->read_tail,
						tty->read_flags);
				c = tty->read_buf[tty->read_tail];
				spin_lock_irqsave(&tty->read_lock, flags);
				tty->read_tail = ((tty->read_tail+1) &
						  (N_TTY_BUF_SIZE-1));
				tty->read_cnt--;
				if (eol) {
					if (--tty->canon_data < 0)
						tty->canon_data = 0;
				}
				spin_unlock_irqrestore(&tty->read_lock, flags);

				if (!eol || (c != __DISABLED_CHAR)) {
					if (tty_put_user(tty, c, b++)) {
						retval = -EFAULT;
						b--;
						break;
					}
					nr--;
				}
				if (eol) {
					tty_audit_push(tty);
					break;
				}
			}
			if (retval)
				break;
		} else {
			int uncopied;
			uncopied = copy_from_read_buf(tty, &b, &nr);
			uncopied += copy_from_read_buf(tty, &b, &nr);
			if (uncopied) {
				retval = -EFAULT;
				break;
			}
		}

		if (n_tty_chars_in_buffer(tty) <= TTY_THRESHOLD_UNTHROTTLE) {
			n_tty_set_room(tty);
			check_unthrottle(tty);
		}

		if (b - buf >= minimum)
			break;
		if (time)
			timeout = time;
	}
	mutex_unlock(&tty->atomic_read_lock);
	remove_wait_queue(&tty->read_wait, &wait);

	if (!waitqueue_active(&tty->read_wait))
		tty->minimum_to_wake = minimum;

	__set_current_state(TASK_RUNNING);
	size = b - buf;
	if (size) {
		retval = size;
		if (nr)
			clear_bit(TTY_PUSH, &tty->flags);
	} else if (test_and_clear_bit(TTY_PUSH, &tty->flags))
		goto do_it_again;

	n_tty_set_room(tty);
	return retval;
}
コード例 #21
0
void gs_close(struct tty_struct * tty, struct file * filp)
{
	unsigned long flags;
	struct gs_port *port;

	func_enter ();

	if (!tty) return;

	port = (struct gs_port *) tty->driver_data;

	if (!port) return;

	if (!port->tty) {
		/* This seems to happen when this is called from vhangup. */
		gs_dprintk (GS_DEBUG_CLOSE, "gs: Odd: port->tty is NULL\n");
		port->tty = tty;
	}

	save_flags(flags); cli();

	if (tty_hung_up_p(filp)) {
		restore_flags(flags);
		port->rd->hungup (port);
		func_exit ();
		return;
	}

	if ((tty->count == 1) && (port->count != 1)) {
		printk(KERN_ERR "gs: gs_close: bad port count;"
		       " tty->count is 1, port count is %d\n", port->count);
		port->count = 1;
	}
	if (--port->count < 0) {
		printk(KERN_ERR "gs: gs_close: bad port count: %d\n", port->count);
		port->count = 0;
	}
	if (port->count) {
		gs_dprintk(GS_DEBUG_CLOSE, "gs_close: count: %d\n", port->count);
		restore_flags(flags);
		func_exit ();
		return;
	}
	port->flags |= ASYNC_CLOSING;

	/*
	 * Save the termios structure, since this port may have
	 * separate termios for callout and dialin.
	 */
	if (port->flags & ASYNC_NORMAL_ACTIVE)
		port->normal_termios = *tty->termios;
	if (port->flags & ASYNC_CALLOUT_ACTIVE)
		port->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 (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
	   tty_wait_until_sent(tty, port->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.
	 */

	port->rd->disable_rx_interrupts (port);

	/* close has no way of returning "EINTR", so discard return value */
	if (port->closing_wait != ASYNC_CLOSING_WAIT_NONE)
		gs_wait_tx_flushed (port, port->closing_wait); 

	port->flags &= ~GS_ACTIVE;

	if (tty->driver.flush_buffer)
		tty->driver.flush_buffer(tty);
	if (tty->ldisc.flush_buffer)
		tty->ldisc.flush_buffer(tty);
	tty->closing = 0;

	port->event = 0;
	port->rd->close (port);
	port->rd->shutdown_port (port);
	port->tty = 0;

	if (port->blocked_open) {
		if (port->close_delay) {
			set_current_state (TASK_INTERRUPTIBLE);
			schedule_timeout(port->close_delay);
		}
		wake_up_interruptible(&port->open_wait);
	}
	port->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
	                 ASYNC_CLOSING | ASYNC_INITIALIZED);
	wake_up_interruptible(&port->close_wait);

	restore_flags(flags);
	func_exit ();
}
コード例 #22
0
static ssize_t write_chan(struct tty_struct * tty, struct file * file,
			  const unsigned char * buf, size_t nr)
{
	const unsigned char *b = buf;
	DECLARE_WAITQUEUE(wait, current);
	int c;
	ssize_t retval = 0;

	/* Job control check -- must be done at start (POSIX.1 7.1.1.4). */
	if (L_TOSTOP(tty) && 
	    file->f_dentry->d_inode->i_rdev != CONSOLE_DEV &&
	    file->f_dentry->d_inode->i_rdev != SYSCONS_DEV) {
		retval = tty_check_change(tty);
		if (retval)
			return retval;
	}

	add_wait_queue(&tty->write_wait, &wait);
	while (1) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (signal_pending(current)) {
			retval = -ERESTARTSYS;
			break;
		}
		if (tty_hung_up_p(file) || (tty->link && !tty->link->count)) {
			retval = -EIO;
			break;
		}
		if (O_OPOST(tty) && !(test_bit(TTY_HW_COOK_OUT, &tty->flags))) {
			while (nr > 0) {
				ssize_t num = opost_block(tty, b, nr);
				if (num < 0) {
					if (num == -EAGAIN)
						break;
					retval = num;
					goto break_out;
				}
				b += num;
				nr -= num;
				if (nr == 0)
					break;
				get_user(c, b);
				if (opost(c, tty) < 0)
					break;
				b++; nr--;
			}
			if (tty->driver.flush_chars)
				tty->driver.flush_chars(tty);
		} else {
			c = tty->driver.write(tty, 1, b, nr);
			if (c < 0) {
				retval = c;
				goto break_out;
			}
			b += c;
			nr -= c;
		}
		if (!nr)
			break;
		if (file->f_flags & O_NONBLOCK) {
			retval = -EAGAIN;
			break;
		}
		schedule();
	}
break_out:
	current->state = TASK_RUNNING;
	remove_wait_queue(&tty->write_wait, &wait);
	return (b - buf) ? b - buf : retval;
}
コード例 #23
0
ファイル: serial.c プロジェクト: rohsaini/mkunity
/*
 * ------------------------------------------------------------
 * 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;
	unsigned long flags;
	int		line;

	if (!info || serial_paranoia_check(info, tty->device, "rs_close")) {
		return;
	}
	
	save_flags(flags); cli();
	
	if (tty_hung_up_p(filp)) {
		restore_flags(flags);
		return;
	}
	
#ifdef SERIAL_DEBUG_OPEN
	printk("rs_close ttys%d, count = %d\n", info->line, info->count);
#endif
	if ((tty->count == 1) && (info->count != 1)) {
		/*
		 * Uh, oh.  tty->count is 1, which means that the tty
		 * structure will be freed.  Info->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.
		 */
		printk("rs_close: bad serial port count; tty->count is 1, "
		       "info->count is %d\n", info->count);
		info->count = 1;
	}
	if (--info->count < 0) {
		printk("rs_close: bad serial port count for ttys%d: %d\n",
		       info->line, info->count);
		info->count = 0;
	}
	if (info->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->normal_termios = *tty->termios;
	if (info->flags & ASYNC_CALLOUT_ACTIVE)
		info->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);

	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;

	line = MINOR(tty->device) - tty->driver.minor_start;

	serial_close_device(info);

	if (info->blocked_open) {
		if (info->close_delay) {
			current->state = TASK_INTERRUPTIBLE;
			current->timeout = jiffies + info->close_delay;
			schedule();
		}
		wake_up_interruptible(&info->open_wait);
	}
	info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CALLOUT_ACTIVE|
			 ASYNC_CLOSING);
	wake_up_interruptible(&info->close_wait);
	restore_flags(flags);
}