static void ssauart_rx_chars (struct uart_port *port)
#endif
{
#if 1

   struct tty_struct *tty = port->info->tty;

   while (1)
   {
      if ((UART_GET_LSR(port) & (1 << 0)) == 0)         /* no more chars available */
         break;

      *tty->flip.char_buf_ptr++ = UART_GET_CHAR(port);
      *tty->flip.flag_buf_ptr++ = TTY_NORMAL;           /* Fixme: we should check for overrun, parity, framing errors etc */
      port->icount.rx++;
      tty->flip.count++;

      if (tty->flip.count >= TTY_FLIPBUF_SIZE)
         break;
   }

   tty_flip_buffer_push (tty);

#else

   struct tty_struct *tty = port->info->tty;

   unsigned int ch;
   unsigned int status;
   unsigned int max_count = 256;

   while (1)
   {
      status = UART_GET_LSR(port);

      if (((status & (1 << 0)) == 0) || (--max_count == 0))
         break;

      if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
         tty->flip.tqueue.routine ((void *) tty);
         if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
            printk (KERN_WARNING "TTY_DONT_FLIP set\n");
            return;
         }
      }

      *tty->flip.char_buf_ptr++ = UART_GET_CHAR(port);
      *tty->flip.flag_buf_ptr++ = TTY_NORMAL;           /* Fixme: we should check for overrun, parity, framing errors etc */
      tty->flip.count++;
      port->icount.rx++;
   }

   tty_flip_buffer_push (tty);

#endif
}
Exemple #2
0
static irqreturn_t ks8695uart_rx_chars(int irq, void *dev_id)
{
	struct uart_port *port = dev_id;
	struct tty_struct *tty = port->info->port.tty;
	unsigned int status, ch, lsr, flg, max_count = 256;

	status = UART_GET_LSR(port);		/* clears pending LSR interrupts */
	while ((status & URLS_URDR) && max_count--) {
		ch = UART_GET_CHAR(port);
		flg = TTY_NORMAL;

		port->icount.rx++;

		/*
		 * Note that the error handling code is
		 * out of the main execution path
		 */
		lsr = UART_GET_LSR(port) | UART_DUMMY_LSR_RX;
		if (unlikely(lsr & (URLS_URBI | URLS_URPE | URLS_URFE | URLS_URROE))) {
			if (lsr & URLS_URBI) {
				lsr &= ~(URLS_URFE | URLS_URPE);
				port->icount.brk++;
				if (uart_handle_break(port))
					goto ignore_char;
			}
			if (lsr & URLS_URPE)
				port->icount.parity++;
			if (lsr & URLS_URFE)
				port->icount.frame++;
			if (lsr & URLS_URROE)
				port->icount.overrun++;

			lsr &= port->read_status_mask;

			if (lsr & URLS_URBI)
				flg = TTY_BREAK;
			else if (lsr & URLS_URPE)
				flg = TTY_PARITY;
			else if (lsr & URLS_URFE)
				flg = TTY_FRAME;
		}

		if (uart_handle_sysrq_char(port, ch))
			goto ignore_char;

		uart_insert_char(port, lsr, URLS_URROE, ch, flg);

ignore_char:
		status = UART_GET_LSR(port);
	}
	tty_flip_buffer_push(tty);

	return IRQ_HANDLED;
}
static u_int ambauart_tx_empty(struct uart_port *port)
{
	unsigned int status;

	status = UART_GET_LSR(port);
	return UART_TX_READY(status) ? TIOCSER_TEMT : 0; 
}
Exemple #4
0
static void ks8695_console_putchar(struct uart_port *port, int ch)
{
	while (!(UART_GET_LSR(port) & URLS_URTHRE))
		barrier();

	UART_PUT_CHAR(port, ch);
}
Exemple #5
0
static void bfin_serial_console_putchar(struct uart_port *port, int ch)
{
	struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
	while (!(UART_GET_LSR(uart) & THRE))
		barrier();
	UART_PUT_CHAR(uart, ch);
}
Exemple #6
0
static __init void early_serial_putc(struct uart_port *port, int ch)
{
	unsigned timeout = 0xffff;
	struct bfin_serial_port *uart = (struct bfin_serial_port *)port;

	while ((!(UART_GET_LSR(uart) & THRE)) && --timeout)
		cpu_relax();
	UART_PUT_CHAR(uart, ch);
}
Exemple #7
0
static void bfin_serial_poll_put_char(struct uart_port *port, unsigned char chr)
{
	struct bfin_serial_port *uart = (struct bfin_serial_port *)port;

	while (!(UART_GET_LSR(uart) & THRE))
		cpu_relax();

	UART_CLEAR_DLAB(uart);
	UART_PUT_CHAR(uart, (unsigned char)chr);
}
Exemple #8
0
/*
 * Return TIOCSER_TEMT when transmitter is not busy.
 */
static unsigned int bfin_serial_tx_empty(struct uart_port *port)
{
	struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
	unsigned short lsr;

	lsr = UART_GET_LSR(uart);
	if (lsr & TEMT)
		return TIOCSER_TEMT;
	else
		return 0;
}
Exemple #9
0
static void bfin_sir_stop_tx(struct bfin_sir_port *port)
{
#ifdef CONFIG_SIR_BFIN_DMA
	disable_dma(port->tx_dma_channel);
#endif

	while (!(UART_GET_LSR(port) & THRE)) {
		cpu_relax();
		continue;
	}

	UART_CLEAR_IER(port, ETBEI);
}
Exemple #10
0
static irqreturn_t bfin_sir_tx_int(int irq, void *dev_id)
{
	struct net_device *dev = dev_id;
	struct bfin_sir_self *self = netdev_priv(dev);
	struct bfin_sir_port *port = self->sir_port;

	spin_lock(&self->lock);
	if (UART_GET_LSR(port) & THRE)
		bfin_sir_tx_chars(dev);
	spin_unlock(&self->lock);

	return IRQ_HANDLED;
}
Exemple #11
0
static int bfin_serial_poll_get_char(struct uart_port *port)
{
	struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
	unsigned char chr;

	while (!(UART_GET_LSR(uart) & DR))
		cpu_relax();

	UART_CLEAR_DLAB(uart);
	chr = UART_GET_CHAR(uart);

	return chr;
}
/* Called with interrupts off only from start_tx() */
static void ssauart_tx_one_char (struct uart_port *port)
{
   struct circ_buf *xmit = &port->info->xmit;

   /* The Fifo may already contain data in which case, our work is
    * done since when it drains it will trigger an interrupt.
    */
   if ((UART_GET_LSR(port) & (1 << 6)) == 0)
      return;

   if (port->x_char)
   {
      UART_PUT_CHAR(port, port->x_char);
      port->x_char = 0;
      port->icount.tx++;
      return;
   }

   if (uart_circ_empty (xmit) || uart_tx_stopped (port))
      return;

   UART_PUT_CHAR(port, xmit->buf[xmit->tail]);
   xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
   port->icount.tx++;

   /*
      If the number of bytes remaining in the SW Tx circular buffer is less
      than WAKEUP_CHARS, wake up tasks trying to write to the UART device.
   */

   if (uart_circ_chars_pending (xmit) < WAKEUP_CHARS)
   {
      uart_write_wakeup (port);

      /*
         If there are no more bytes to transmit, disable Tx interrupts.
         (We don't need to refill the UART Tx fifo when it next becomes empty).
      */

      if (uart_circ_empty (xmit))
         ssauart_stop_tx (port, 0);
   }
}
Exemple #13
0
/*
 * interrupts are disabled on entry
 */
static void bfin_serial_stop_tx(struct uart_port *port)
{
	struct bfin_serial_port *uart = (struct bfin_serial_port *)port;
#ifdef CONFIG_SERIAL_BFIN_DMA
	struct circ_buf *xmit = &uart->port.info->xmit;
#endif

	while (!(UART_GET_LSR(uart) & TEMT))
		cpu_relax();

#ifdef CONFIG_SERIAL_BFIN_DMA
	disable_dma(uart->tx_dma_channel);
	xmit->tail = (xmit->tail + uart->tx_count) & (UART_XMIT_SIZE - 1);
	uart->port.icount.tx += uart->tx_count;
	uart->tx_count = 0;
	uart->tx_done = 1;
#else
#ifdef CONFIG_BF54x
	/* Clear TFI bit */
	UART_PUT_LSR(uart, TFI);
#endif
	UART_CLEAR_IER(uart, ETBEI);
#endif
}
Exemple #14
0
static unsigned int ks8695uart_tx_empty(struct uart_port *port)
{
	return (UART_GET_LSR(port) & URLS_URTE) ? TIOCSER_TEMT : 0;
}
Exemple #15
0
static int bfin_sir_set_speed(struct bfin_sir_port *port, int speed)
{
	int ret = -EINVAL;
	unsigned int quot;
	unsigned short val, lsr, lcr;
	static int utime;
	int count = 10;

	lcr = WLS(8);

	switch (speed) {
	case 9600:
	case 19200:
	case 38400:
	case 57600:
	case 115200:

		/*
		 * IRDA is not affected by anomaly 05000230, so there is no
		 * need to tweak the divisor like he UART driver (which will
		 * slightly speed up the baud rate on us).
		 */
		quot = (port->clk + (8 * speed)) / (16 * speed);

		do {
			udelay(utime);
			lsr = UART_GET_LSR(port);
		} while (!(lsr & TEMT) && count--);

		/* The useconds for 1 bits to transmit */
		utime = 1000000 / speed + 1;

		/* Clear UCEN bit to reset the UART state machine
		 * and control registers
		 */
		val = UART_GET_GCTL(port);
		val &= ~UCEN;
		UART_PUT_GCTL(port, val);

		/* Set DLAB in LCR to Access THR RBR IER */
		UART_SET_DLAB(port);
		SSYNC();

		UART_PUT_DLL(port, quot & 0xFF);
		UART_PUT_DLH(port, (quot >> 8) & 0xFF);
		SSYNC();

		/* Clear DLAB in LCR */
		UART_CLEAR_DLAB(port);
		SSYNC();

		UART_PUT_LCR(port, lcr);

		val = UART_GET_GCTL(port);
		val |= UCEN;
		UART_PUT_GCTL(port, val);

		ret = 0;
		break;
	default:
		printk(KERN_WARNING "bfin_sir: Invalid speed %d\n", speed);
		break;
	}

	val = UART_GET_GCTL(port);
	/* If not add the 'RPOLC', we can't catch the receive interrupt.
	 * It's related with the HW layout and the IR transiver.
	 */
	val |= IREN | RPOLC;
	UART_PUT_GCTL(port, val);
	return ret;
}
static u_int ssauart_tx_empty (struct uart_port *port)
{
   return UART_GET_LSR(port) & (1 << 6) ? TIOCSER_TEMT : 0;
}
Exemple #17
0
static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = NULL;
	unsigned int status, ch, flg;
	static struct timeval anomaly_start = { .tv_sec = 0 };

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

 	ch = UART_GET_CHAR(uart);
 	uart->port.icount.rx++;

#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
	if (kgdb_connected && kgdboc_port_line == uart->port.line)
		if (ch == 0x3) {/* Ctrl + C */
			kgdb_breakpoint();
			return;
		}

	if (!uart->port.info || !uart->port.info->tty)
		return;
#endif
	tty = uart->port.info->tty;

	if (ANOMALY_05000363) {
		/* The BF533 (and BF561) family of processors have a nice anomaly
		 * where they continuously generate characters for a "single" break.
		 * We have to basically ignore this flood until the "next" valid
		 * character comes across.  Due to the nature of the flood, it is
		 * not possible to reliably catch bytes that are sent too quickly
		 * after this break.  So application code talking to the Blackfin
		 * which sends a break signal must allow at least 1.5 character
		 * times after the end of the break for things to stabilize.  This
		 * timeout was picked as it must absolutely be larger than 1
		 * character time +/- some percent.  So 1.5 sounds good.  All other
		 * Blackfin families operate properly.  Woo.
		 */
		if (anomaly_start.tv_sec) {
			struct timeval curr;
			suseconds_t usecs;

			if ((~ch & (~ch + 1)) & 0xff)
				goto known_good_char;

			do_gettimeofday(&curr);
			if (curr.tv_sec - anomaly_start.tv_sec > 1)
				goto known_good_char;

			usecs = 0;
			if (curr.tv_sec != anomaly_start.tv_sec)
				usecs += USEC_PER_SEC;
			usecs += curr.tv_usec - anomaly_start.tv_usec;

			if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
				goto known_good_char;

			if (ch)
				anomaly_start.tv_sec = 0;
			else
				anomaly_start = curr;

			return;

 known_good_char:
			status &= ~BI;
			anomaly_start.tv_sec = 0;
		}
	}

	if (status & BI) {
		if (ANOMALY_05000363)
			if (bfin_revid() < 5)
				do_gettimeofday(&anomaly_start);
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	if (uart_handle_sysrq_char(&uart->port, ch))
		goto ignore_char;

	uart_insert_char(&uart->port, status, OE, ch, flg);

 ignore_char:
	tty_flip_buffer_push(tty);
}

static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.info->xmit;

	/*
	 * Check the modem control lines before
	 * transmitting anything.
	 */
	bfin_serial_mctrl_check(uart);

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
#ifdef CONFIG_BF54x
		/* Clear TFI bit */
		UART_PUT_LSR(uart, TFI);
#endif
		UART_CLEAR_IER(uart, ETBEI);
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
		UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		uart->port.icount.tx++;
		SSYNC();
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&uart->port);
}

static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

	spin_lock(&uart->port.lock);
	while (UART_GET_LSR(uart) & DR)
		bfin_serial_rx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}

static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

	spin_lock(&uart->port.lock);
	if (UART_GET_LSR(uart) & THRE)
		bfin_serial_tx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}
#endif

#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.info->xmit;

	uart->tx_done = 0;

	/*
	 * Check the modem control lines before
	 * transmitting anything.
	 */
	bfin_serial_mctrl_check(uart);

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
		uart->tx_count = 0;
		uart->tx_done = 1;
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
	if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
		uart->tx_count = UART_XMIT_SIZE - xmit->tail;
	blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
					(unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
	set_dma_config(uart->tx_dma_channel,
		set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
			INTR_ON_BUF,
			DIMENSION_LINEAR,
			DATA_SIZE_8,
			DMA_SYNC_RESTART));
	set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
	set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
	set_dma_x_modify(uart->tx_dma_channel, 1);
	enable_dma(uart->tx_dma_channel);

	UART_SET_IER(uart, ETBEI);
}

static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = uart->port.info->port.tty;
	int i, flg, status;

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

	uart->port.icount.rx +=
		CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
		UART_XMIT_SIZE);

	if (status & BI) {
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto dma_ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	for (i = uart->rx_dma_buf.tail; i != uart->rx_dma_buf.head; i++) {
		if (i >= UART_XMIT_SIZE)
			i = 0;
		if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
			uart_insert_char(&uart->port, status, OE,
				uart->rx_dma_buf.buf[i], flg);
	}

 dma_ignore_char:
	tty_flip_buffer_push(tty);
}

void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
{
	int x_pos, pos, flags;

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

	uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
	x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
	uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
	if (uart->rx_dma_nrows == DMA_RX_YCOUNT)
		uart->rx_dma_nrows = 0;
	x_pos = DMA_RX_XCOUNT - x_pos;
	if (x_pos == DMA_RX_XCOUNT)
		x_pos = 0;

	pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
	if (pos != uart->rx_dma_buf.tail) {
		uart->rx_dma_buf.head = pos;
		bfin_serial_dma_rx_chars(uart);
		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
	}

	spin_unlock_irqrestore(&uart->port.lock, flags);

	mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
}
Exemple #18
0
static void bfin_serial_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = NULL;
	unsigned int status, ch, flg;
	static struct timeval anomaly_start = { .tv_sec = 0 };

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

 	ch = UART_GET_CHAR(uart);
 	uart->port.icount.rx++;

#if defined(CONFIG_KGDB_SERIAL_CONSOLE) || \
	defined(CONFIG_KGDB_SERIAL_CONSOLE_MODULE)
	if (kgdb_connected && kgdboc_port_line == uart->port.line
		&& kgdboc_break_enabled)
		if (ch == 0x3) {/* Ctrl + C */
			kgdb_breakpoint();
			return;
		}

	if (!uart->port.state || !uart->port.state->port.tty)
		return;
#endif
	tty = uart->port.state->port.tty;

	if (ANOMALY_05000363) {
		/* The BF533 (and BF561) family of processors have a nice anomaly
		 * where they continuously generate characters for a "single" break.
		 * We have to basically ignore this flood until the "next" valid
		 * character comes across.  Due to the nature of the flood, it is
		 * not possible to reliably catch bytes that are sent too quickly
		 * after this break.  So application code talking to the Blackfin
		 * which sends a break signal must allow at least 1.5 character
		 * times after the end of the break for things to stabilize.  This
		 * timeout was picked as it must absolutely be larger than 1
		 * character time +/- some percent.  So 1.5 sounds good.  All other
		 * Blackfin families operate properly.  Woo.
		 */
		if (anomaly_start.tv_sec) {
			struct timeval curr;
			suseconds_t usecs;

			if ((~ch & (~ch + 1)) & 0xff)
				goto known_good_char;

			do_gettimeofday(&curr);
			if (curr.tv_sec - anomaly_start.tv_sec > 1)
				goto known_good_char;

			usecs = 0;
			if (curr.tv_sec != anomaly_start.tv_sec)
				usecs += USEC_PER_SEC;
			usecs += curr.tv_usec - anomaly_start.tv_usec;

			if (usecs > UART_GET_ANOMALY_THRESHOLD(uart))
				goto known_good_char;

			if (ch)
				anomaly_start.tv_sec = 0;
			else
				anomaly_start = curr;

			return;

 known_good_char:
			status &= ~BI;
			anomaly_start.tv_sec = 0;
		}
	}

	if (status & BI) {
		if (ANOMALY_05000363)
			if (bfin_revid() < 5)
				do_gettimeofday(&anomaly_start);
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	if (uart_handle_sysrq_char(&uart->port, ch))
		goto ignore_char;

	uart_insert_char(&uart->port, status, OE, ch, flg);

 ignore_char:
	tty_flip_buffer_push(tty);
}

static void bfin_serial_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.state->xmit;

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
#ifdef CONFIG_BF54x
		/* Clear TFI bit */
		UART_PUT_LSR(uart, TFI);
#endif
		/* Anomaly notes:
		 *  05000215 -	we always clear ETBEI within last UART TX
		 *		interrupt to end a string. It is always set
		 *		when start a new tx.
		 */
		UART_CLEAR_IER(uart, ETBEI);
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	while ((UART_GET_LSR(uart) & THRE) && xmit->tail != xmit->head) {
		UART_PUT_CHAR(uart, xmit->buf[xmit->tail]);
		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
		uart->port.icount.tx++;
	}

	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
		uart_write_wakeup(&uart->port);
}

static irqreturn_t bfin_serial_rx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

	while (UART_GET_LSR(uart) & DR)
		bfin_serial_rx_chars(uart);

	return IRQ_HANDLED;
}

static irqreturn_t bfin_serial_tx_int(int irq, void *dev_id)
{
	struct bfin_serial_port *uart = dev_id;

#ifdef CONFIG_SERIAL_BFIN_HARD_CTSRTS
	if (uart->scts && !(bfin_serial_get_mctrl(&uart->port) & TIOCM_CTS)) {
		uart->scts = 0;
		uart_handle_cts_change(&uart->port, uart->scts);
	}
#endif
	spin_lock(&uart->port.lock);
	if (UART_GET_LSR(uart) & THRE)
		bfin_serial_tx_chars(uart);
	spin_unlock(&uart->port.lock);

	return IRQ_HANDLED;
}
#endif

#ifdef CONFIG_SERIAL_BFIN_DMA
static void bfin_serial_dma_tx_chars(struct bfin_serial_port *uart)
{
	struct circ_buf *xmit = &uart->port.state->xmit;

	uart->tx_done = 0;

	if (uart_circ_empty(xmit) || uart_tx_stopped(&uart->port)) {
		uart->tx_count = 0;
		uart->tx_done = 1;
		return;
	}

	if (uart->port.x_char) {
		UART_PUT_CHAR(uart, uart->port.x_char);
		uart->port.icount.tx++;
		uart->port.x_char = 0;
	}

	uart->tx_count = CIRC_CNT(xmit->head, xmit->tail, UART_XMIT_SIZE);
	if (uart->tx_count > (UART_XMIT_SIZE - xmit->tail))
		uart->tx_count = UART_XMIT_SIZE - xmit->tail;
	blackfin_dcache_flush_range((unsigned long)(xmit->buf+xmit->tail),
					(unsigned long)(xmit->buf+xmit->tail+uart->tx_count));
	set_dma_config(uart->tx_dma_channel,
		set_bfin_dma_config(DIR_READ, DMA_FLOW_STOP,
			INTR_ON_BUF,
			DIMENSION_LINEAR,
			DATA_SIZE_8,
			DMA_SYNC_RESTART));
	set_dma_start_addr(uart->tx_dma_channel, (unsigned long)(xmit->buf+xmit->tail));
	set_dma_x_count(uart->tx_dma_channel, uart->tx_count);
	set_dma_x_modify(uart->tx_dma_channel, 1);
	SSYNC();
	enable_dma(uart->tx_dma_channel);

	UART_SET_IER(uart, ETBEI);
}

static void bfin_serial_dma_rx_chars(struct bfin_serial_port *uart)
{
	struct tty_struct *tty = uart->port.state->port.tty;
	int i, flg, status;

	status = UART_GET_LSR(uart);
	UART_CLEAR_LSR(uart);

	uart->port.icount.rx +=
		CIRC_CNT(uart->rx_dma_buf.head, uart->rx_dma_buf.tail,
		UART_XMIT_SIZE);

	if (status & BI) {
		uart->port.icount.brk++;
		if (uart_handle_break(&uart->port))
			goto dma_ignore_char;
		status &= ~(PE | FE);
	}
	if (status & PE)
		uart->port.icount.parity++;
	if (status & OE)
		uart->port.icount.overrun++;
	if (status & FE)
		uart->port.icount.frame++;

	status &= uart->port.read_status_mask;

	if (status & BI)
		flg = TTY_BREAK;
	else if (status & PE)
		flg = TTY_PARITY;
	else if (status & FE)
		flg = TTY_FRAME;
	else
		flg = TTY_NORMAL;

	for (i = uart->rx_dma_buf.tail; ; i++) {
		if (i >= UART_XMIT_SIZE)
			i = 0;
		if (i == uart->rx_dma_buf.head)
			break;
		if (!uart_handle_sysrq_char(&uart->port, uart->rx_dma_buf.buf[i]))
			uart_insert_char(&uart->port, status, OE,
				uart->rx_dma_buf.buf[i], flg);
	}

 dma_ignore_char:
	tty_flip_buffer_push(tty);
}

void bfin_serial_rx_dma_timeout(struct bfin_serial_port *uart)
{
	int x_pos, pos;

	dma_disable_irq_nosync(uart->rx_dma_channel);
	spin_lock_bh(&uart->rx_lock);

	/* 2D DMA RX buffer ring is used. Because curr_y_count and
	 * curr_x_count can't be read as an atomic operation,
	 * curr_y_count should be read before curr_x_count. When
	 * curr_x_count is read, curr_y_count may already indicate
	 * next buffer line. But, the position calculated here is
	 * still indicate the old line. The wrong position data may
	 * be smaller than current buffer tail, which cause garbages
	 * are received if it is not prohibit.
	 */
	uart->rx_dma_nrows = get_dma_curr_ycount(uart->rx_dma_channel);
	x_pos = get_dma_curr_xcount(uart->rx_dma_channel);
	uart->rx_dma_nrows = DMA_RX_YCOUNT - uart->rx_dma_nrows;
	if (uart->rx_dma_nrows == DMA_RX_YCOUNT || x_pos == 0)
		uart->rx_dma_nrows = 0;
	x_pos = DMA_RX_XCOUNT - x_pos;
	if (x_pos == DMA_RX_XCOUNT)
		x_pos = 0;

	pos = uart->rx_dma_nrows * DMA_RX_XCOUNT + x_pos;
	/* Ignore receiving data if new position is in the same line of
	 * current buffer tail and small.
	 */
	if (pos > uart->rx_dma_buf.tail ||
		uart->rx_dma_nrows < (uart->rx_dma_buf.tail/DMA_RX_XCOUNT)) {
		uart->rx_dma_buf.head = pos;
		bfin_serial_dma_rx_chars(uart);
		uart->rx_dma_buf.tail = uart->rx_dma_buf.head;
	}

	spin_unlock_bh(&uart->rx_lock);
	dma_enable_irq(uart->rx_dma_channel);

	mod_timer(&(uart->rx_dma_timer), jiffies + DMA_RX_FLUSH_JIFFIES);
}
static void ambauart_int(int irq, void *dev_id, struct pt_regs *regs)
{
    struct uart_port *port = dev_id;
    struct uart_info *info = port->info;
    unsigned int status, ier, old_ier, count, lsr;

    old_ier  = UART_GET_IER(port);
    UART_PUT_IER(port, (old_ier & 0xFFFFF0FF));

    status = UART_GET_INT_STATUS(port);
    
    lsr = UART_GET_LSR(port);
    
    /* KS8695_INTMASK_UART_RX is not set during breakpoint as it should (looks
     * like a HW bug), so we specifically check for a breakpoint condition in
     * the UART line status register.
     * Some bits from the UART line status register are cleared only when they
     * are read by CPU. That is why we cannot read the line status register
     * twice, and should pass the first read as argument to ambauart_rx_chars.
     * Refer to CENTAUR KS8695PX's Register Description document:
     * KS8695PX_REG_DESCP_v1.0.pdf, page 58: "UART Line Status Register".
     */
    if (status & KS8695_INTMASK_UART_RX || lsr & KS8695_UART_LINES_BE)
    {
#ifdef SUPPORT_SYSRQ
	ambauart_rx_chars(port, regs, lsr);
#else
	ambauart_rx_chars(port, lsr);
#endif
    }
    if (status & KS8695_INTMASK_UART_TX) 
    {
        if (port->x_char)
        {
                UART_CLR_INT_STATUS(port, KS8695_INTMASK_UART_TX);
                UART_PUT_CHAR(port, (u_int) port->x_char);
                port->icount.tx++;
                port->x_char = 0;
                ier = UART_GET_IER(port);
                ier &= 0xFFFFFEFF;
                UART_PUT_IER(port, ier);
                printk("XOn/Off sent\n");
                return;
        }
        for ( count = 0; count < 16; count++)
        {
              if (info->xmit.head == info->xmit.tail)
              {
                 /*ier = UART_GET_IER(port);
                 ier &= 0xFFFFFEFF;
                 UART_PUT_IER(port, ier);*/
                 break;
              }
              UART_CLR_INT_STATUS(port, KS8695_INTMASK_UART_TX);
              UART_PUT_CHAR(port, (u_int) (info->xmit.buf[info->xmit.tail]));
              info->xmit.tail = (info->xmit.tail + 1) & (UART_XMIT_SIZE - 1);
              port->icount.tx++;
        };
        if (CIRC_CNT(info->xmit.head, info->xmit.tail, UART_XMIT_SIZE) < WAKEUP_CHARS)
                uart_write_wakeup(port);
 
        if (info->xmit.head == info->xmit.tail)
        {
           ier = UART_GET_IER(port);
           ier &= 0xFFFFFEFF;
           UART_PUT_IER(port, ier);
        }
    }
    if (status & KS8695_INTMASK_UART_MODEMS)
    {
	ambauart_modem_status(port);
    }
    if (status & KS8695_INTMASK_UART_MODEMS)
    {
         ambauart_modem_status(port);
    }
    if ( status & KS8695_INTMASK_UART_LINE_ERR)
    {
         UART_GET_LSR(port);
    }
    if (info->xmit.head == info->xmit.tail)
       UART_PUT_IER(port, (old_ier & 0xFFFFFEFF));
    else
       UART_PUT_IER(port, old_ier | KS8695_INTMASK_UART_TX);
}
ambauart_rx_chars(struct uart_port *port, unsigned short status)
#endif
{
	struct tty_struct *tty = port->info->tty;
	unsigned short ch, lsr, max_count = 256;
	
	while (UART_RX_DATA(status) && max_count--) {
	    lsr = status;
		if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
			tty->flip.tqueue.routine((void *)tty);
			if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
				printk(KERN_WARNING "TTY_DONT_FLIP set\n");
				return;
			}
		}

		ch = UART_GET_CHAR(port);

		*tty->flip.char_buf_ptr = ch;
		*tty->flip.flag_buf_ptr = TTY_NORMAL;
		port->icount.rx++;

		/*
		 * Note that the error handling code is
		 * out of the main execution path
		 */
		lsr |= UART_DUMMY_LSR_RX;

		if (lsr & KS8695_UART_LINES_ANY) {
			if (lsr & KS8695_UART_LINES_BE) {
				lsr &= ~(KS8695_UART_LINES_FE | KS8695_UART_LINES_PE);
				port->icount.brk++;
				if (uart_handle_break(port))
					goto ignore_char;
			} else if (lsr & KS8695_UART_LINES_PE)
				port->icount.parity++;
			else if (lsr & KS8695_UART_LINES_FE)
				port->icount.frame++;
			if (lsr & KS8695_UART_LINES_OE)
				port->icount.overrun++;

			lsr &= port->read_status_mask;

			if (lsr & KS8695_UART_LINES_BE)
				*tty->flip.flag_buf_ptr = TTY_BREAK;
			else if (lsr & KS8695_UART_LINES_PE)
				*tty->flip.flag_buf_ptr = TTY_PARITY;
			else if (lsr & KS8695_UART_LINES_FE)
				*tty->flip.flag_buf_ptr = TTY_FRAME;
		}

		if (uart_handle_sysrq_char(port, ch, regs))
			goto ignore_char;

		if ((lsr & port->ignore_status_mask) == 0) {
			tty->flip.flag_buf_ptr++;
			tty->flip.char_buf_ptr++;
			tty->flip.count++;
		}
		if ((lsr & KS8695_UART_LINES_OE) &&
		    tty->flip.count < TTY_FLIPBUF_SIZE) {
			/*
			 * Overrun is special, since it's reported
			 * immediately, and doesn't affect the current
			 * character
			 */
			*tty->flip.char_buf_ptr++ = 0;
			*tty->flip.flag_buf_ptr++ = TTY_OVERRUN;
			tty->flip.count++;
		}
	ignore_char:
		status = UART_GET_LSR(port);
	}
	tty_flip_buffer_push(tty);
	return;
}