Commit a2237a2d authored by Daeseok Youn's avatar Daeseok Youn Committed by Greg Kroah-Hartman
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staging: dgnc: re-arrange functions for removing 



Re-arrange the functions for removing forward declarations in dgnc_cls.c file.

Signed-off-by: default avatarDaeseok Youn <daeseok.youn@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent c23b48e0

drivers/staging/dgnc/dgnc_cls.c

+460 −489
Original line number Diff line number Diff line
@@ -26,56 +26,6 @@ 
#include "dgnc_cls.h"

#include "dgnc_tty.h"



static inline void cls_parse_isr(struct dgnc_board *brd, uint port);

static inline void cls_clear_break(struct channel_t *ch, int force);

static inline void cls_set_cts_flow_control(struct channel_t *ch);

static inline void cls_set_rts_flow_control(struct channel_t *ch);

static inline void cls_set_ixon_flow_control(struct channel_t *ch);

static inline void cls_set_ixoff_flow_control(struct channel_t *ch);

static inline void cls_set_no_output_flow_control(struct channel_t *ch);

static inline void cls_set_no_input_flow_control(struct channel_t *ch);

static void cls_parse_modem(struct channel_t *ch, unsigned char signals);

static void cls_tasklet(unsigned long data);

static void cls_vpd(struct dgnc_board *brd);

static void cls_uart_init(struct channel_t *ch);

static void cls_uart_off(struct channel_t *ch);

static int cls_drain(struct tty_struct *tty, uint seconds);

static void cls_param(struct tty_struct *tty);

static void cls_assert_modem_signals(struct channel_t *ch);

static void cls_flush_uart_write(struct channel_t *ch);

static void cls_flush_uart_read(struct channel_t *ch);

static void cls_disable_receiver(struct channel_t *ch);

static void cls_enable_receiver(struct channel_t *ch);

static void cls_send_break(struct channel_t *ch, int msecs);

static void cls_send_start_character(struct channel_t *ch);

static void cls_send_stop_character(struct channel_t *ch);

static void cls_copy_data_from_uart_to_queue(struct channel_t *ch);

static void cls_copy_data_from_queue_to_uart(struct channel_t *ch);

static uint cls_get_uart_bytes_left(struct channel_t *ch);

static void cls_send_immediate_char(struct channel_t *ch, unsigned char);

static irqreturn_t cls_intr(int irq, void *voidbrd);



struct board_ops dgnc_cls_ops = {

	.tasklet =			cls_tasklet,

	.intr =				cls_intr,

	.uart_init =			cls_uart_init,

	.uart_off =			cls_uart_off,

	.drain =			cls_drain,

	.param =			cls_param,

	.vpd =				cls_vpd,

	.assert_modem_signals =		cls_assert_modem_signals,

	.flush_uart_write =		cls_flush_uart_write,

	.flush_uart_read =		cls_flush_uart_read,

	.disable_receiver =		cls_disable_receiver,

	.enable_receiver =		cls_enable_receiver,

	.send_break =			cls_send_break,

	.send_start_character =		cls_send_start_character,

	.send_stop_character =		cls_send_stop_character,

	.copy_data_from_queue_to_uart = cls_copy_data_from_queue_to_uart,

	.get_uart_bytes_left =		cls_get_uart_bytes_left,

	.send_immediate_char =		cls_send_immediate_char

};



static inline void cls_set_cts_flow_control(struct channel_t *ch)

{

	unsigned char lcrb = readb(&ch->ch_cls_uart->lcr);
@@ -357,138 +307,418 @@ static inline void cls_clear_break(struct channel_t *ch, int force) 
	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



/* Parse the ISR register for the specific port */

static inline void cls_parse_isr(struct dgnc_board *brd, uint port)

static void cls_copy_data_from_uart_to_queue(struct channel_t *ch)

{

	struct channel_t *ch;

	unsigned char isr = 0;

	int qleft = 0;

	unsigned char linestatus = 0;

	unsigned char error_mask = 0;

	ushort head;

	ushort tail;

	unsigned long flags;



	/*

	 * No need to verify board pointer, it was already

	 * verified in the interrupt routine.

	 */



	if (port >= brd->nasync)

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	ch = brd->channels[port];

	if (ch->magic != DGNC_CHANNEL_MAGIC)

		return;

	spin_lock_irqsave(&ch->ch_lock, flags);



	/* cache head and tail of queue */

	head = ch->ch_r_head;

	tail = ch->ch_r_tail;



	/* Store how much space we have left in the queue */

	qleft = tail - head - 1;

	if (qleft < 0)

		qleft += RQUEUEMASK + 1;



	/*

	 * Create a mask to determine whether we should

	 * insert the character (if any) into our queue.

	 */

	if (ch->ch_c_iflag & IGNBRK)

		error_mask |= UART_LSR_BI;



	/* Here we try to figure out what caused the interrupt to happen */

	while (1) {

		isr = readb(&ch->ch_cls_uart->isr_fcr);

		linestatus = readb(&ch->ch_cls_uart->lsr);



		/* Bail if no pending interrupt on port */

		if (isr & UART_IIR_NO_INT)

		if (!(linestatus & (UART_LSR_DR)))

			break;



		/* Receive Interrupt pending */

		if (isr & (UART_IIR_RDI | UART_IIR_RDI_TIMEOUT)) {

			/* Read data from uart -> queue */

			brd->intr_rx++;

			ch->ch_intr_rx++;

			cls_copy_data_from_uart_to_queue(ch);

			dgnc_check_queue_flow_control(ch);

		}



		/* Transmit Hold register empty pending */

		if (isr & UART_IIR_THRI) {

			/* Transfer data (if any) from Write Queue -> UART. */

			spin_lock_irqsave(&ch->ch_lock, flags);

			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);

			brd->intr_tx++;

			ch->ch_intr_tx++;

			spin_unlock_irqrestore(&ch->ch_lock, flags);

			cls_copy_data_from_queue_to_uart(ch);

		/*

		 * Discard character if we are ignoring the error mask.

		*/

		if (linestatus & error_mask)  {

			linestatus = 0;

			readb(&ch->ch_cls_uart->txrx);

			continue;

		}



		/* CTS/RTS change of state */

		if (isr & UART_IIR_CTSRTS) {

			brd->intr_modem++;

			ch->ch_intr_modem++;

		/*

			 * Don't need to do anything, the cls_parse_modem

			 * below will grab the updated modem signals.

		 * If our queue is full, we have no choice but to drop some

		 * data. The assumption is that HWFLOW or SWFLOW should have

		 * stopped things way way before we got to this point.

		 *

		 * I decided that I wanted to ditch the oldest data first,

		 * I hope thats okay with everyone? Yes? Good.

		 */

		while (qleft < 1) {

			tail = (tail + 1) & RQUEUEMASK;

			ch->ch_r_tail = tail;

			ch->ch_err_overrun++;

			qleft++;

		}



		/* Parse any modem signal changes */

		cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));

	}

		ch->ch_equeue[head] = linestatus & (UART_LSR_BI | UART_LSR_PE

								 | UART_LSR_FE);

		ch->ch_rqueue[head] = readb(&ch->ch_cls_uart->txrx);



		qleft--;



		if (ch->ch_equeue[head] & UART_LSR_PE)

			ch->ch_err_parity++;

		if (ch->ch_equeue[head] & UART_LSR_BI)

			ch->ch_err_break++;

		if (ch->ch_equeue[head] & UART_LSR_FE)

			ch->ch_err_frame++;



		/* Add to, and flip head if needed */

		head = (head + 1) & RQUEUEMASK;

		ch->ch_rxcount++;

	}



	/*

 * cls_param()

 * Send any/all changes to the line to the UART.

	 * Write new final heads to channel structure.

	 */

static void cls_param(struct tty_struct *tty)

	ch->ch_r_head = head & RQUEUEMASK;

	ch->ch_e_head = head & EQUEUEMASK;



	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



/* Make the UART raise any of the output signals we want up */

static void cls_assert_modem_signals(struct channel_t *ch)

{

	unsigned char lcr = 0;

	unsigned char uart_lcr = 0;

	unsigned char ier = 0;

	unsigned char uart_ier = 0;

	uint baud = 9600;

	int quot = 0;

	struct dgnc_board *bd;

	struct channel_t *ch;

	struct un_t   *un;

	unsigned char out;



	if (!tty || tty->magic != TTY_MAGIC)

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	un = (struct un_t *)tty->driver_data;

	if (!un || un->magic != DGNC_UNIT_MAGIC)

		return;

	out = ch->ch_mostat;



	if (ch->ch_flags & CH_LOOPBACK)

		out |= UART_MCR_LOOP;



	writeb(out, &ch->ch_cls_uart->mcr);



	/* Give time for the UART to actually drop the signals */

	udelay(10);

}



static void cls_copy_data_from_queue_to_uart(struct channel_t *ch)

{

	ushort head;

	ushort tail;

	int n;

	int qlen;

	uint len_written = 0;

	unsigned long flags;



	ch = un->un_ch;

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	bd = ch->ch_bd;

	if (!bd || bd->magic != DGNC_BOARD_MAGIC)

		return;

	spin_lock_irqsave(&ch->ch_lock, flags);



	/*

	 * If baud rate is zero, flush queues, and set mval to drop DTR.

	 */

	if ((ch->ch_c_cflag & (CBAUD)) == 0) {

		ch->ch_r_head = 0;

		ch->ch_r_tail = 0;

		ch->ch_e_head = 0;

		ch->ch_e_tail = 0;

		ch->ch_w_head = 0;

		ch->ch_w_tail = 0;

	/* No data to write to the UART */

	if (ch->ch_w_tail == ch->ch_w_head)

		goto exit_unlock;



		cls_flush_uart_write(ch);

		cls_flush_uart_read(ch);

	/* If port is "stopped", don't send any data to the UART */

	if ((ch->ch_flags & CH_FORCED_STOP) ||

	    (ch->ch_flags & CH_BREAK_SENDING))

		goto exit_unlock;



		/* The baudrate is B0 so all modem lines are to be dropped. */

		ch->ch_flags |= (CH_BAUD0);

		ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);

		cls_assert_modem_signals(ch);

		ch->ch_old_baud = 0;

		return;

	} else if (ch->ch_custom_speed) {

		baud = ch->ch_custom_speed;

		/* Handle transition from B0 */

		if (ch->ch_flags & CH_BAUD0) {

			ch->ch_flags &= ~(CH_BAUD0);

	if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))

		goto exit_unlock;



	n = 32;



	/* cache head and tail of queue */

	head = ch->ch_w_head & WQUEUEMASK;

	tail = ch->ch_w_tail & WQUEUEMASK;

	qlen = (head - tail) & WQUEUEMASK;



	/* Find minimum of the FIFO space, versus queue length */

	n = min(n, qlen);



	while (n > 0) {

		/*

			 * Bring back up RTS and DTR...

			 * Also handle RTS or DTR toggle if set.

		 * If RTS Toggle mode is on, turn on RTS now if not already set,

		 * and make sure we get an event when the data transfer has

		 * completed.

		 */

			if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))

		if (ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE) {

			if (!(ch->ch_mostat & UART_MCR_RTS)) {

				ch->ch_mostat |= (UART_MCR_RTS);

			if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))

				cls_assert_modem_signals(ch);

			}

			ch->ch_tun.un_flags |= (UN_EMPTY);

		}



		/*

		 * If DTR Toggle mode is on, turn on DTR now if not already set,

		 * and make sure we get an event when the data transfer has

		 * completed.

		 */

		if (ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE) {

			if (!(ch->ch_mostat & UART_MCR_DTR)) {

				ch->ch_mostat |= (UART_MCR_DTR);

				cls_assert_modem_signals(ch);

			}

			ch->ch_tun.un_flags |= (UN_EMPTY);

		}

		writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_cls_uart->txrx);

		ch->ch_w_tail++;

		ch->ch_w_tail &= WQUEUEMASK;

		ch->ch_txcount++;

		len_written++;

		n--;

	}



	} else {

		int iindex = 0;

		int jindex = 0;

	if (len_written > 0)

		ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);



exit_unlock:

	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



static void cls_parse_modem(struct channel_t *ch, unsigned char signals)

{

	unsigned char msignals = signals;

	unsigned long flags;



	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	/*

	 * Do altpin switching. Altpin switches DCD and DSR.

	 * This prolly breaks DSRPACE, so we should be more clever here.

	 */

	spin_lock_irqsave(&ch->ch_lock, flags);

	if (ch->ch_digi.digi_flags & DIGI_ALTPIN) {

		unsigned char mswap = signals;



		if (mswap & UART_MSR_DDCD) {

			msignals &= ~UART_MSR_DDCD;

			msignals |= UART_MSR_DDSR;

		}

		if (mswap & UART_MSR_DDSR) {

			msignals &= ~UART_MSR_DDSR;

			msignals |= UART_MSR_DDCD;

		}

		if (mswap & UART_MSR_DCD) {

			msignals &= ~UART_MSR_DCD;

			msignals |= UART_MSR_DSR;

		}

		if (mswap & UART_MSR_DSR) {

			msignals &= ~UART_MSR_DSR;

			msignals |= UART_MSR_DCD;

		}

	}

	spin_unlock_irqrestore(&ch->ch_lock, flags);



	/*

	 * Scrub off lower bits. They signify delta's, which I don't

	 * care about

	 */

	signals &= 0xf0;



	spin_lock_irqsave(&ch->ch_lock, flags);

	if (msignals & UART_MSR_DCD)

		ch->ch_mistat |= UART_MSR_DCD;

	else

		ch->ch_mistat &= ~UART_MSR_DCD;



	if (msignals & UART_MSR_DSR)

		ch->ch_mistat |= UART_MSR_DSR;

	else

		ch->ch_mistat &= ~UART_MSR_DSR;



	if (msignals & UART_MSR_RI)

		ch->ch_mistat |= UART_MSR_RI;

	else

		ch->ch_mistat &= ~UART_MSR_RI;



	if (msignals & UART_MSR_CTS)

		ch->ch_mistat |= UART_MSR_CTS;

	else

		ch->ch_mistat &= ~UART_MSR_CTS;

	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



/* Parse the ISR register for the specific port */

static inline void cls_parse_isr(struct dgnc_board *brd, uint port)

{

	struct channel_t *ch;

	unsigned char isr = 0;

	unsigned long flags;



	/*

	 * No need to verify board pointer, it was already

	 * verified in the interrupt routine.

	 */



	if (port >= brd->nasync)

		return;



	ch = brd->channels[port];

	if (ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	/* Here we try to figure out what caused the interrupt to happen */

	while (1) {

		isr = readb(&ch->ch_cls_uart->isr_fcr);



		/* Bail if no pending interrupt on port */

		if (isr & UART_IIR_NO_INT)

			break;



		/* Receive Interrupt pending */

		if (isr & (UART_IIR_RDI | UART_IIR_RDI_TIMEOUT)) {

			/* Read data from uart -> queue */

			brd->intr_rx++;

			ch->ch_intr_rx++;

			cls_copy_data_from_uart_to_queue(ch);

			dgnc_check_queue_flow_control(ch);

		}



		/* Transmit Hold register empty pending */

		if (isr & UART_IIR_THRI) {

			/* Transfer data (if any) from Write Queue -> UART. */

			spin_lock_irqsave(&ch->ch_lock, flags);

			ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);

			brd->intr_tx++;

			ch->ch_intr_tx++;

			spin_unlock_irqrestore(&ch->ch_lock, flags);

			cls_copy_data_from_queue_to_uart(ch);

		}



		/* CTS/RTS change of state */

		if (isr & UART_IIR_CTSRTS) {

			brd->intr_modem++;

			ch->ch_intr_modem++;

			/*

			 * Don't need to do anything, the cls_parse_modem

			 * below will grab the updated modem signals.

			 */

		}



		/* Parse any modem signal changes */

		cls_parse_modem(ch, readb(&ch->ch_cls_uart->msr));

	}

}



/* Channel lock MUST be held before calling this function! */

static void cls_flush_uart_write(struct channel_t *ch)

{

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT),

	       &ch->ch_cls_uart->isr_fcr);

	usleep_range(10, 20);



	ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);

}



/* Channel lock MUST be held before calling this function! */

static void cls_flush_uart_read(struct channel_t *ch)

{

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	/*

	 * For complete POSIX compatibility, we should be purging the

	 * read FIFO in the UART here.

	 *

	 * However, clearing the read FIFO (UART_FCR_CLEAR_RCVR) also

	 * incorrectly flushes write data as well as just basically trashing the

	 * FIFO.

	 *

	 * Presumably, this is a bug in this UART.

	 */



	udelay(10);

}



/*

 * cls_param()

 * Send any/all changes to the line to the UART.

 */

static void cls_param(struct tty_struct *tty)

{

	unsigned char lcr = 0;

	unsigned char uart_lcr = 0;

	unsigned char ier = 0;

	unsigned char uart_ier = 0;

	uint baud = 9600;

	int quot = 0;

	struct dgnc_board *bd;

	struct channel_t *ch;

	struct un_t   *un;



	if (!tty || tty->magic != TTY_MAGIC)

		return;



	un = (struct un_t *)tty->driver_data;

	if (!un || un->magic != DGNC_UNIT_MAGIC)

		return;



	ch = un->un_ch;

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	bd = ch->ch_bd;

	if (!bd || bd->magic != DGNC_BOARD_MAGIC)

		return;



	/*

	 * If baud rate is zero, flush queues, and set mval to drop DTR.

	 */

	if ((ch->ch_c_cflag & (CBAUD)) == 0) {

		ch->ch_r_head = 0;

		ch->ch_r_tail = 0;

		ch->ch_e_head = 0;

		ch->ch_e_tail = 0;

		ch->ch_w_head = 0;

		ch->ch_w_tail = 0;



		cls_flush_uart_write(ch);

		cls_flush_uart_read(ch);



		/* The baudrate is B0 so all modem lines are to be dropped. */

		ch->ch_flags |= (CH_BAUD0);

		ch->ch_mostat &= ~(UART_MCR_RTS | UART_MCR_DTR);

		cls_assert_modem_signals(ch);

		ch->ch_old_baud = 0;

		return;

	} else if (ch->ch_custom_speed) {

		baud = ch->ch_custom_speed;

		/* Handle transition from B0 */

		if (ch->ch_flags & CH_BAUD0) {

			ch->ch_flags &= ~(CH_BAUD0);



			/*

			 * Bring back up RTS and DTR...

			 * Also handle RTS or DTR toggle if set.

			 */

			if (!(ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE))

				ch->ch_mostat |= (UART_MCR_RTS);

			if (!(ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE))

				ch->ch_mostat |= (UART_MCR_DTR);

		}



	} else {

		int iindex = 0;

		int jindex = 0;



		ulong bauds[4][16] = {

			{ /* slowbaud */
@@ -804,109 +1034,22 @@ static void cls_enable_receiver(struct channel_t *ch) 
	writeb(tmp, &ch->ch_cls_uart->ier);

}



static void cls_copy_data_from_uart_to_queue(struct channel_t *ch)

/*

 * This function basically goes to sleep for secs, or until

 * it gets signalled that the port has fully drained.

 */

static int cls_drain(struct tty_struct *tty, uint seconds)

{

	int qleft = 0;

	unsigned char linestatus = 0;

	unsigned char error_mask = 0;

	ushort head;

	ushort tail;

	unsigned long flags;

	struct channel_t *ch;

	struct un_t *un;



	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;

	if (!tty || tty->magic != TTY_MAGIC)

		return -ENXIO;



	spin_lock_irqsave(&ch->ch_lock, flags);



	/* cache head and tail of queue */

	head = ch->ch_r_head;

	tail = ch->ch_r_tail;



	/* Store how much space we have left in the queue */

	qleft = tail - head - 1;

	if (qleft < 0)

		qleft += RQUEUEMASK + 1;



	/*

	 * Create a mask to determine whether we should

	 * insert the character (if any) into our queue.

	 */

	if (ch->ch_c_iflag & IGNBRK)

		error_mask |= UART_LSR_BI;



	while (1) {

		linestatus = readb(&ch->ch_cls_uart->lsr);



		if (!(linestatus & (UART_LSR_DR)))

			break;



		/*

		 * Discard character if we are ignoring the error mask.

		*/

		if (linestatus & error_mask)  {

			linestatus = 0;

			readb(&ch->ch_cls_uart->txrx);

			continue;

		}



		/*

		 * If our queue is full, we have no choice but to drop some

		 * data. The assumption is that HWFLOW or SWFLOW should have

		 * stopped things way way before we got to this point.

		 *

		 * I decided that I wanted to ditch the oldest data first,

		 * I hope thats okay with everyone? Yes? Good.

		 */

		while (qleft < 1) {

			tail = (tail + 1) & RQUEUEMASK;

			ch->ch_r_tail = tail;

			ch->ch_err_overrun++;

			qleft++;

		}



		ch->ch_equeue[head] = linestatus & (UART_LSR_BI | UART_LSR_PE

								 | UART_LSR_FE);

		ch->ch_rqueue[head] = readb(&ch->ch_cls_uart->txrx);



		qleft--;



		if (ch->ch_equeue[head] & UART_LSR_PE)

			ch->ch_err_parity++;

		if (ch->ch_equeue[head] & UART_LSR_BI)

			ch->ch_err_break++;

		if (ch->ch_equeue[head] & UART_LSR_FE)

			ch->ch_err_frame++;



		/* Add to, and flip head if needed */

		head = (head + 1) & RQUEUEMASK;

		ch->ch_rxcount++;

	}



	/*

	 * Write new final heads to channel structure.

	 */

	ch->ch_r_head = head & RQUEUEMASK;

	ch->ch_e_head = head & EQUEUEMASK;



	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



/*

 * This function basically goes to sleep for secs, or until

 * it gets signalled that the port has fully drained.

 */

static int cls_drain(struct tty_struct *tty, uint seconds)

{

	unsigned long flags;

	struct channel_t *ch;

	struct un_t *un;



	if (!tty || tty->magic != TTY_MAGIC)

		return -ENXIO;



	un = (struct un_t *)tty->driver_data;

	if (!un || un->magic != DGNC_UNIT_MAGIC)

		return -ENXIO;

	un = (struct un_t *)tty->driver_data;

	if (!un || un->magic != DGNC_UNIT_MAGIC)

		return -ENXIO;



	ch = un->un_ch;

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
@@ -926,199 +1069,6 @@ static int cls_drain(struct tty_struct *tty, uint seconds) 
					 ((un->un_flags & UN_EMPTY) == 0));

}



/* Channel lock MUST be held before calling this function! */

static void cls_flush_uart_write(struct channel_t *ch)

{

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	writeb((UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_XMIT),

	       &ch->ch_cls_uart->isr_fcr);

	usleep_range(10, 20);



	ch->ch_flags |= (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);

}



/* Channel lock MUST be held before calling this function! */

static void cls_flush_uart_read(struct channel_t *ch)

{

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	/*

	 * For complete POSIX compatibility, we should be purging the

	 * read FIFO in the UART here.

	 *

	 * However, clearing the read FIFO (UART_FCR_CLEAR_RCVR) also

	 * incorrectly flushes write data as well as just basically trashing the

	 * FIFO.

	 *

	 * Presumably, this is a bug in this UART.

	 */



	udelay(10);

}



static void cls_copy_data_from_queue_to_uart(struct channel_t *ch)

{

	ushort head;

	ushort tail;

	int n;

	int qlen;

	uint len_written = 0;

	unsigned long flags;



	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	spin_lock_irqsave(&ch->ch_lock, flags);



	/* No data to write to the UART */

	if (ch->ch_w_tail == ch->ch_w_head)

		goto exit_unlock;



	/* If port is "stopped", don't send any data to the UART */

	if ((ch->ch_flags & CH_FORCED_STOP) ||

	    (ch->ch_flags & CH_BREAK_SENDING))

		goto exit_unlock;



	if (!(ch->ch_flags & (CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM)))

		goto exit_unlock;



	n = 32;



	/* cache head and tail of queue */

	head = ch->ch_w_head & WQUEUEMASK;

	tail = ch->ch_w_tail & WQUEUEMASK;

	qlen = (head - tail) & WQUEUEMASK;



	/* Find minimum of the FIFO space, versus queue length */

	n = min(n, qlen);



	while (n > 0) {

		/*

		 * If RTS Toggle mode is on, turn on RTS now if not already set,

		 * and make sure we get an event when the data transfer has

		 * completed.

		 */

		if (ch->ch_digi.digi_flags & DIGI_RTS_TOGGLE) {

			if (!(ch->ch_mostat & UART_MCR_RTS)) {

				ch->ch_mostat |= (UART_MCR_RTS);

				cls_assert_modem_signals(ch);

			}

			ch->ch_tun.un_flags |= (UN_EMPTY);

		}



		/*

		 * If DTR Toggle mode is on, turn on DTR now if not already set,

		 * and make sure we get an event when the data transfer has

		 * completed.

		 */

		if (ch->ch_digi.digi_flags & DIGI_DTR_TOGGLE) {

			if (!(ch->ch_mostat & UART_MCR_DTR)) {

				ch->ch_mostat |= (UART_MCR_DTR);

				cls_assert_modem_signals(ch);

			}

			ch->ch_tun.un_flags |= (UN_EMPTY);

		}

		writeb(ch->ch_wqueue[ch->ch_w_tail], &ch->ch_cls_uart->txrx);

		ch->ch_w_tail++;

		ch->ch_w_tail &= WQUEUEMASK;

		ch->ch_txcount++;

		len_written++;

		n--;

	}



	if (len_written > 0)

		ch->ch_flags &= ~(CH_TX_FIFO_EMPTY | CH_TX_FIFO_LWM);



exit_unlock:

	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



static void cls_parse_modem(struct channel_t *ch, unsigned char signals)

{

	unsigned char msignals = signals;

	unsigned long flags;



	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	/*

	 * Do altpin switching. Altpin switches DCD and DSR.

	 * This prolly breaks DSRPACE, so we should be more clever here.

	 */

	spin_lock_irqsave(&ch->ch_lock, flags);

	if (ch->ch_digi.digi_flags & DIGI_ALTPIN) {

		unsigned char mswap = signals;



		if (mswap & UART_MSR_DDCD) {

			msignals &= ~UART_MSR_DDCD;

			msignals |= UART_MSR_DDSR;

		}

		if (mswap & UART_MSR_DDSR) {

			msignals &= ~UART_MSR_DDSR;

			msignals |= UART_MSR_DDCD;

		}

		if (mswap & UART_MSR_DCD) {

			msignals &= ~UART_MSR_DCD;

			msignals |= UART_MSR_DSR;

		}

		if (mswap & UART_MSR_DSR) {

			msignals &= ~UART_MSR_DSR;

			msignals |= UART_MSR_DCD;

		}

	}

	spin_unlock_irqrestore(&ch->ch_lock, flags);



	/*

	 * Scrub off lower bits. They signify delta's, which I don't

	 * care about

	 */

	signals &= 0xf0;



	spin_lock_irqsave(&ch->ch_lock, flags);

	if (msignals & UART_MSR_DCD)

		ch->ch_mistat |= UART_MSR_DCD;

	else

		ch->ch_mistat &= ~UART_MSR_DCD;



	if (msignals & UART_MSR_DSR)

		ch->ch_mistat |= UART_MSR_DSR;

	else

		ch->ch_mistat &= ~UART_MSR_DSR;



	if (msignals & UART_MSR_RI)

		ch->ch_mistat |= UART_MSR_RI;

	else

		ch->ch_mistat &= ~UART_MSR_RI;



	if (msignals & UART_MSR_CTS)

		ch->ch_mistat |= UART_MSR_CTS;

	else

		ch->ch_mistat &= ~UART_MSR_CTS;

	spin_unlock_irqrestore(&ch->ch_lock, flags);

}



/* Make the UART raise any of the output signals we want up */

static void cls_assert_modem_signals(struct channel_t *ch)

{

	unsigned char out;



	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)

		return;



	out = ch->ch_mostat;



	if (ch->ch_flags & CH_LOOPBACK)

		out |= UART_MCR_LOOP;



	writeb(out, &ch->ch_cls_uart->mcr);



	/* Give time for the UART to actually drop the signals */

	udelay(10);

}



static void cls_send_start_character(struct channel_t *ch)

{

	if (!ch || ch->magic != DGNC_CHANNEL_MAGIC)
@@ -1298,3 +1248,24 @@ static void cls_vpd(struct dgnc_board *brd) 


	iounmap(re_map_vpdbase);

}



struct board_ops dgnc_cls_ops = {

	.tasklet =			cls_tasklet,

	.intr =				cls_intr,

	.uart_init =			cls_uart_init,

	.uart_off =			cls_uart_off,

	.drain =			cls_drain,

	.param =			cls_param,

	.vpd =				cls_vpd,

	.assert_modem_signals =		cls_assert_modem_signals,

	.flush_uart_write =		cls_flush_uart_write,

	.flush_uart_read =		cls_flush_uart_read,

	.disable_receiver =		cls_disable_receiver,

	.enable_receiver =		cls_enable_receiver,

	.send_break =			cls_send_break,

	.send_start_character =		cls_send_start_character,

	.send_stop_character =		cls_send_stop_character,

	.copy_data_from_queue_to_uart = cls_copy_data_from_queue_to_uart,

	.get_uart_bytes_left =		cls_get_uart_bytes_left,

	.send_immediate_char =		cls_send_immediate_char

};