/*
* -------------------------------------------------------------------
* shutdown ()
*
* This routine will shutdown a serial port; interrupts are disabled, and
* DTR is dropped if the hangup on close termio flag is on.
* -------------------------------------------------------------------
*/
static void shutdown(struct dz_serial *info)
{
unsigned long flags;
unsigned short tmp;
if (!info->is_initialized)
return;
save_flags(flags);
cli();
dz_stop(info->tty);
info->cflags &= ~DZ_CREAD; /* turn off receive enable flag */
dz_out(info, DZ_LPR, info->cflags);
if (info->xmit_buf) { /* free Tx buffer */
free_page((unsigned long) info->xmit_buf);
info->xmit_buf = 0;
}
if (!info->tty || (info->tty->termios->c_cflag & HUPCL)) {
tmp = dz_in(info, DZ_TCR);
if (tmp & DZ_MODEM_DTR) {
tmp &= ~DZ_MODEM_DTR;
dz_out(info, DZ_TCR, tmp);
}
}
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
info->is_initialized = 0;
restore_flags(flags);
}
static int __init dz_console_setup(struct console *co, char *options)
{
struct dz_port *dport = &dz_ports[CONSOLE_LINE];
int baud = 9600;
int bits = 8;
int parity = 'n';
int flow = 'n';
int ret;
unsigned short mask, tmp;
if (options)
uart_parse_options(options, &baud, &parity, &bits, &flow);
dz_reset(dport);
ret = uart_set_options(&dport->port, co, baud, parity, bits, flow);
if (ret == 0) {
mask = 1 << dport->port.line;
tmp = dz_in(dport, DZ_TCR); /* read the TX flag */
if (!(tmp & mask)) {
tmp |= mask; /* set the TX flag */
dz_out(dport, DZ_TCR, tmp);
}
}
return ret;
}
/*
* This routine sends a break character out the serial port.
*/
static void send_break(struct dz_serial *info, int duration)
{
unsigned long flags;
unsigned short tmp, mask;
if (!info->port)
return;
mask = 1 << info->line;
tmp = dz_in(info, DZ_TCR);
tmp |= mask;
current->state = TASK_INTERRUPTIBLE;
save_flags(flags);
cli();
dz_out(info, DZ_TCR, tmp);
schedule_timeout(duration);
tmp &= ~mask;
dz_out(info, DZ_TCR, tmp);
restore_flags(flags);
}
/*
* get_lsr_info - get line status register info
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
*/
static unsigned int dz_tx_empty(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned short status = dz_in(dport, DZ_LPR);
/* FIXME: this appears to be obviously broken --rmk. */
return status ? TIOCSER_TEMT : 0;
}
static void dz_reset(struct dz_port *dport)
{
dz_out(dport, DZ_CSR, DZ_CLR);
while (dz_in(dport, DZ_CSR) & DZ_CLR);
iob();
/* enable scanning */
dz_out(dport, DZ_CSR, DZ_MSE);
}
/*
* -------------------------------------------------------------------
* dz_tx_empty() -- get the transmitter empty status
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
* -------------------------------------------------------------------
*/
static unsigned int dz_tx_empty(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned short tmp, mask = 1 << dport->port.line;
tmp = dz_in(dport, DZ_TCR);
tmp &= mask;
return tmp ? 0 : TIOCSER_TEMT;
}
/*
* -------------------------------------------------------------------
* startup ()
*
* various initialization tasks
* -------------------------------------------------------------------
*/
static int startup(struct dz_serial *info)
{
unsigned long page, flags;
unsigned short tmp;
if (info->is_initialized)
return 0;
save_flags(flags);
cli();
if (!info->port) {
if (info->tty)
set_bit(TTY_IO_ERROR, &info->tty->flags);
restore_flags(flags);
return -ENODEV;
}
if (!info->xmit_buf) {
page = get_free_page(GFP_KERNEL);
if (!page) {
restore_flags(flags);
return -ENOMEM;
}
info->xmit_buf = (unsigned char *) page;
}
if (info->tty)
clear_bit(TTY_IO_ERROR, &info->tty->flags);
/* enable the interrupt and the scanning */
tmp = dz_in(info, DZ_CSR);
tmp |= (DZ_RIE | DZ_TIE | DZ_MSE);
dz_out(info, DZ_CSR, tmp);
info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
/* set up the speed */
change_speed(info);
/* clear the line transmitter buffer
I can't figure out why I need to do this - but
its necessary - in order for the console portion
and the interrupt portion to live happily side by side.
*/
/* clear the line transmitter buffer
I can't figure out why I need to do this - but
its necessary - in order for the console portion
and the interrupt portion to live happily side by side.
*/
info->is_initialized = 1;
restore_flags(flags);
return 0;
}
static void dz_start(struct tty_struct *tty)
{
struct dz_serial *info = (struct dz_serial *) tty->driver_data;
unsigned short mask, tmp;
mask = 1 << info->line;
tmp = dz_in(info, DZ_TCR); /* read the TX flag */
tmp |= mask; /* set the TX flag */
dz_out(info, DZ_TCR, tmp);
}
static void dz_start_tx(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned short tmp, mask = 1 << dport->port.line;
unsigned long flags;
spin_lock_irqsave(&dport->port.lock, flags);
tmp = dz_in(dport, DZ_TCR); /* read the TX flag */
tmp |= mask; /* set the TX flag */
dz_out(dport, DZ_TCR, tmp);
spin_unlock_irqrestore(&dport->port.lock, flags);
}
static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned short tmp;
if (dport->port.line == DZ_MODEM) {
tmp = dz_in(dport, DZ_TCR);
if (mctrl & TIOCM_DTR)
tmp &= ~DZ_MODEM_DTR;
else
tmp |= DZ_MODEM_DTR;
dz_out(dport, DZ_TCR, tmp);
}
}
/*
* ------------------------------------------------------------
* check_modem_status ()
*
* Only valid for the MODEM line duh !
* ------------------------------------------------------------
*/
static inline void check_modem_status(struct dz_serial *info)
{
unsigned short status;
/* if not ne modem line just return */
if (info->line != DZ_MODEM)
return;
status = dz_in(info, DZ_MSR);
/* it's easy, since DSR2 is the only bit in the register */
if (status)
info->icount.dsr++;
}
static unsigned int dz_get_mctrl(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
if (dport->port.line == DZ_MODEM) {
/*
* CHECKME: This is a guess from the other code... --rmk
*/
if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
mctrl &= ~TIOCM_DSR;
}
return mctrl;
}
/*
* ------------------------------------------------------------
* dz_interrupt ()
*
* this is the main interrupt routine for the DZ chip.
* It deals with the multiple ports.
* ------------------------------------------------------------
*/
static void dz_interrupt(int irq, void *dev, struct pt_regs *regs)
{
struct dz_serial *info;
unsigned short status;
/* get the reason why we just got an irq */
status = dz_in((struct dz_serial *) dev, DZ_CSR);
info = lines[LINE(status)]; /* re-arrange info the proper port */
if (status & DZ_RDONE)
receive_chars(info); /* the receive function */
if (status & DZ_TRDY)
transmit_chars(info);
}
static void dz_break_ctl(struct uart_port *uport, int break_state)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
unsigned short tmp, mask = 1 << uport->line;
spin_lock_irqsave(&uport->lock, flags);
tmp = dz_in(dport, DZ_TCR);
if (break_state)
tmp |= mask;
else
tmp &= ~mask;
dz_out(dport, DZ_TCR, tmp);
spin_unlock_irqrestore(&uport->lock, flags);
}
/*
* -------------------------------------------------------------------
* dz_console_putchar() -- transmit a character
*
* Polled transmission. This is tricky. We need to mask transmit
* interrupts so that they do not interfere, enable the transmitter
* for the line requested and then wait till the transmit scanner
* requests data for this line. But it may request data for another
* line first, in which case we have to disable its transmitter and
* repeat waiting till our line pops up. Only then the character may
* be transmitted. Finally, the state of the transmitter mask is
* restored. Welcome to the world of PDP-11!
* -------------------------------------------------------------------
*/
static void dz_console_putchar(struct uart_port *uport, int ch)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
unsigned short csr, tcr, trdy, mask;
int loops = 10000;
spin_lock_irqsave(&dport->port.lock, flags);
csr = dz_in(dport, DZ_CSR);
dz_out(dport, DZ_CSR, csr & ~DZ_TIE);
tcr = dz_in(dport, DZ_TCR);
tcr |= 1 << dport->port.line;
mask = tcr;
dz_out(dport, DZ_TCR, mask);
iob();
spin_unlock_irqrestore(&dport->port.lock, flags);
while (loops--) {
trdy = dz_in(dport, DZ_CSR);
if (!(trdy & DZ_TRDY))
continue;
trdy = (trdy & DZ_TLINE) >> 8;
if (trdy == dport->port.line)
break;
mask &= ~(1 << trdy);
dz_out(dport, DZ_TCR, mask);
iob();
udelay(2);
}
if (loops) /* Cannot send otherwise. */
dz_out(dport, DZ_TDR, ch);
dz_out(dport, DZ_TCR, tcr);
dz_out(dport, DZ_CSR, csr);
}
static unsigned int dz_get_mctrl(struct uart_port *uport)
{
/*
* FIXME: Handle the 3100/5000 as appropriate. --macro
*/
struct dz_port *dport = (struct dz_port *)uport;
unsigned int mctrl = TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
if (dport->port.line == DZ_MODEM) {
if (dz_in(dport, DZ_MSR) & DZ_MODEM_DSR)
mctrl &= ~TIOCM_DSR;
}
return mctrl;
}
static void dz_stop(struct tty_struct *tty)
{
struct dz_serial *info;
unsigned short mask, tmp;
if (tty == 0)
return;
info = (struct dz_serial *) tty->driver_data;
mask = 1 << info->line;
tmp = dz_in(info, DZ_TCR); /* read the TX flag */
tmp &= ~mask; /* clear the TX flag */
dz_out(info, DZ_TCR, tmp);
}
/*
* ------------------------------------------------------------
* dz_interrupt ()
*
* this is the main interrupt routine for the DZ chip.
* It deals with the multiple ports.
* ------------------------------------------------------------
*/
static irqreturn_t dz_interrupt(int irq, void *dev)
{
struct dz_port *dport = (struct dz_port *)dev;
unsigned short status;
/* get the reason why we just got an irq */
status = dz_in(dport, DZ_CSR);
if ((status & (DZ_RDONE | DZ_RIE)) == (DZ_RDONE | DZ_RIE))
dz_receive_chars(dport, regs);
if ((status & (DZ_TRDY | DZ_TIE)) == (DZ_TRDY | DZ_TIE))
dz_transmit_chars(dport);
return IRQ_HANDLED;
}
/*
* -------------------------------------------------------------------
* startup ()
*
* various initialization tasks
* -------------------------------------------------------------------
*/
static int dz_startup(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
unsigned short tmp;
spin_lock_irqsave(&dport->port.lock, flags);
/* enable the interrupt and the scanning */
tmp = dz_in(dport, DZ_CSR);
tmp |= DZ_RIE | DZ_TIE | DZ_MSE;
dz_out(dport, DZ_CSR, tmp);
spin_unlock_irqrestore(&dport->port.lock, flags);
return 0;
}
static void dz_set_mctrl(struct uart_port *uport, unsigned int mctrl)
{
/*
* FIXME: Handle the 3100/5000 as appropriate. --macro
*/
struct dz_port *dport = (struct dz_port *)uport;
unsigned short tmp;
if (dport->port.line == DZ_MODEM) {
tmp = dz_in(dport, DZ_TCR);
if (mctrl & TIOCM_DTR)
tmp &= ~DZ_MODEM_DTR;
else
tmp |= DZ_MODEM_DTR;
dz_out(dport, DZ_TCR, tmp);
}
}
static void dz_break_ctl(struct uart_port *uport, int break_state)
{
/*
* FIXME: Can't access BREAK bits in TDR easily;
* reuse the code for polled TX. --macro
*/
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
unsigned short tmp, mask = 1 << dport->port.line;
spin_lock_irqsave(&uport->lock, flags);
tmp = dz_in(dport, DZ_TCR);
if (break_state)
tmp |= mask;
else
tmp &= ~mask;
dz_out(dport, DZ_TCR, tmp);
spin_unlock_irqrestore(&uport->lock, flags);
}
/*
* ------------------------------------------------------------
* dz_interrupt ()
*
* this is the main interrupt routine for the DZ chip.
* It deals with the multiple ports.
* ------------------------------------------------------------
*/
static irqreturn_t dz_interrupt(int irq, void *dev, struct pt_regs *regs)
{
struct dz_port *dport;
unsigned short status;
/* get the reason why we just got an irq */
status = dz_in((struct dz_port *)dev, DZ_CSR);
dport = &dz_ports[LINE(status)];
if (status & DZ_RDONE)
dz_receive_chars(dport);
if (status & DZ_TRDY)
dz_transmit_chars(dport);
/* FIXME: what about check modem status??? --rmk */
return IRQ_HANDLED;
}
/*
* ------------------------------------------------------------
* check_modem_status()
*
* DS 3100 & 5100: Only valid for the MODEM line, duh!
* DS 5000/200: Valid for the MODEM and PRINTER line.
* ------------------------------------------------------------
*/
static inline void check_modem_status(struct dz_port *dport)
{
/*
* FIXME:
* 1. No status change interrupt; use a timer.
* 2. Handle the 3100/5000 as appropriate. --macro
*/
unsigned short status;
/* If not the modem line just return. */
if (dport->port.line != DZ_MODEM)
return;
status = dz_in(dport, DZ_MSR);
/* it's easy, since DSR2 is the only bit in the register */
if (status)
dport->port.icount.dsr++;
}
static void dz_console_put_char(struct dz_port *dport, unsigned char ch)
{
unsigned long flags;
int loops = 2500;
unsigned short tmp = ch;
/* this code sends stuff out to serial device - spinning its
wheels and waiting. */
spin_lock_irqsave(&dport->port.lock, flags);
/* spin our wheels */
while (((dz_in(dport, DZ_CSR) & DZ_TRDY) != DZ_TRDY) && loops--)
/* FIXME: cpu_relax, udelay? --rmk */
;
/* Actually transmit the character. */
dz_out(dport, DZ_TDR, tmp);
spin_unlock_irqrestore(&dport->port.lock, flags);
}
/*
* ------------------------------------------------------------
* transmit_char ()
*
* This routine deals with outputs to any lines.
* ------------------------------------------------------------
*/
static inline void dz_transmit_chars(struct dz_port *dport_in)
{
struct dz_port *dport;
struct circ_buf *xmit;
unsigned short status;
unsigned char tmp;
status = dz_in(dport_in, DZ_CSR);
dport = &dz_ports[LINE(status)];
xmit = &dport->port.info->xmit;
if (dport->port.x_char) { /* XON/XOFF chars */
dz_out(dport, DZ_TDR, dport->port.x_char);
dport->port.icount.tx++;
dport->port.x_char = 0;
return;
}
/* If nothing to do or stopped or hardware stopped. */
if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
dz_stop_tx(&dport->port);
return;
}
/*
* If something to do... (remember the dz has no output fifo,
* so we go one char at a time) :-<
*/
tmp = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
dz_out(dport, DZ_TDR, tmp);
dport->port.icount.tx++;
if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
uart_write_wakeup(&dport->port);
/* Are we are done. */
if (uart_circ_empty(xmit))
dz_stop_tx(&dport->port);
}
static void dz_console_put_char(unsigned char ch)
{
unsigned long flags;
int loops = 2500;
unsigned short tmp = ch;
/* this code sends stuff out to serial device - spinning its
wheels and waiting. */
/* force the issue - point it at lines[3] */
dz_console = &multi[CONSOLE_LINE];
save_flags(flags);
cli();
/* spin our wheels */
while (((dz_in(dz_console, DZ_CSR) & DZ_TRDY) != DZ_TRDY) && loops--);
/* Actually transmit the character. */
dz_out(dz_console, DZ_TDR, tmp);
restore_flags(flags);
}
/*
* -------------------------------------------------------------------
* startup ()
*
* various initialization tasks
* -------------------------------------------------------------------
*/
static int dz_startup(struct uart_port *uport)
{
struct dz_port *dport = (struct dz_port *)uport;
unsigned long flags;
unsigned short tmp;
/* The dz lines for the mouse/keyboard must be
* opened using their respective drivers.
*/
if ((dport->port.line == DZ_KEYBOARD) ||
(dport->port.line == DZ_MOUSE))
return -ENODEV;
spin_lock_irqsave(&dport->port.lock, flags);
/* enable the interrupt and the scanning */
tmp = dz_in(dport, DZ_CSR);
tmp |= DZ_RIE | DZ_TIE | DZ_MSE;
dz_out(dport, DZ_CSR, tmp);
spin_unlock_irqrestore(&dport->port.lock, flags);
return 0;
}
/*
* get_lsr_info - get line status register info
*
* Purpose: Let user call ioctl() to get info when the UART physically
* is emptied. On bus types like RS485, the transmitter must
* release the bus after transmitting. This must be done when
* the transmit shift register is empty, not be done when the
* transmit holding register is empty. This functionality
* allows an RS485 driver to be written in user space.
*/
static int get_lsr_info(struct dz_serial *info, unsigned int *value)
{
unsigned short status = dz_in(info, DZ_LPR);
return put_user(status, value);
}
/*
* ------------------------------------------------------------
* receive_char ()
*
* This routine deals with inputs from any lines.
* ------------------------------------------------------------
*/
static inline void dz_receive_chars(struct dz_port *dport_in,
struct pt_regs *regs)
{
struct dz_port *dport;
struct tty_struct *tty = NULL;
struct uart_icount *icount;
int lines_rx[DZ_NB_PORT] = { [0 ... DZ_NB_PORT - 1] = 0 };
unsigned short status;
unsigned char ch, flag;
int i;
while ((status = dz_in(dport_in, DZ_RBUF)) & DZ_DVAL) {
dport = &dz_ports[LINE(status)];
tty = dport->port.info->tty; /* point to the proper dev */
ch = UCHAR(status); /* grab the char */
icount = &dport->port.icount;
icount->rx++;
flag = TTY_NORMAL;
if (status & DZ_FERR) { /* frame error */
/*
* There is no separate BREAK status bit, so
* treat framing errors as BREAKs for Magic SysRq
* and SAK; normally, otherwise.
*/
if (uart_handle_break(&dport->port))
continue;
if (dport->port.flags & UPF_SAK)
flag = TTY_BREAK;
else
flag = TTY_FRAME;
} else if (status & DZ_OERR) /* overrun error */
flag = TTY_OVERRUN;
else if (status & DZ_PERR) /* parity error */
flag = TTY_PARITY;
/* keep track of the statistics */
switch (flag) {
case TTY_FRAME:
icount->frame++;
break;
case TTY_PARITY:
icount->parity++;
break;
case TTY_OVERRUN:
icount->overrun++;
break;
case TTY_BREAK:
icount->brk++;
break;
default:
break;
}
if (uart_handle_sysrq_char(&dport->port, ch, regs))
continue;
if ((status & dport->port.ignore_status_mask) == 0) {
uart_insert_char(&dport->port,
status, DZ_OERR, ch, flag);
lines_rx[LINE(status)] = 1;
}
}
for (i = 0; i < DZ_NB_PORT; i++)
if (lines_rx[i])
tty_flip_buffer_push(dz_ports[i].port.info->tty);
}
/*
* ------------------------------------------------------------
* receive_char ()
*
* This routine deals with inputs from any lines.
* ------------------------------------------------------------
*/
static inline void dz_receive_chars(struct dz_port *dport)
{
struct tty_struct *tty = NULL;
struct uart_icount *icount;
int ignore = 0;
unsigned short status, tmp;
unsigned char ch, flag;
/* this code is going to be a problem...
the call to tty_flip_buffer is going to need
to be rethought...
*/
do {
status = dz_in(dport, DZ_RBUF);
/* punt so we don't get duplicate characters */
if (!(status & DZ_DVAL))
goto ignore_char;
ch = UCHAR(status); /* grab the char */
flag = TTY_NORMAL;
#if 0
if (info->is_console) {
if (ch == 0)
return; /* it's a break ... */
}
#endif
tty = dport->port.info->tty;/* now tty points to the proper dev */
icount = &dport->port.icount;
if (!tty)
break;
if (tty->flip.count >= TTY_FLIPBUF_SIZE)
break;
icount->rx++;
/* keep track of the statistics */
if (status & (DZ_OERR | DZ_FERR | DZ_PERR)) {
if (status & DZ_PERR) /* parity error */
icount->parity++;
else if (status & DZ_FERR) /* frame error */
icount->frame++;
if (status & DZ_OERR) /* overrun error */
icount->overrun++;
/* check to see if we should ignore the character
and mask off conditions that should be ignored
*/
if (status & dport->port.ignore_status_mask) {
if (++ignore > 100)
break;
goto ignore_char;
}
/* mask off the error conditions we want to ignore */
tmp = status & dport->port.read_status_mask;
if (tmp & DZ_PERR) {
flag = TTY_PARITY;
#ifdef DEBUG_DZ
debug_console("PERR\n", 5);
#endif
} else if (tmp & DZ_FERR) {
flag = TTY_FRAME;
#ifdef DEBUG_DZ
debug_console("FERR\n", 5);
#endif
}
if (tmp & DZ_OERR) {
#ifdef DEBUG_DZ
debug_console("OERR\n", 5);
#endif
tty_insert_flip_char(tty, ch, flag);
ch = 0;
flag = TTY_OVERRUN;
}
}
tty_insert_flip_char(tty, ch, flag);
ignore_char:
} while (status & DZ_DVAL);
if (tty)
tty_flip_buffer_push(tty);
}
/*
* ------------------------------------------------------------
* transmit_char ()
*
* This routine deals with outputs to any lines.
* ------------------------------------------------------------
*/
static inline void dz_transmit_chars(struct dz_port *dport)
{
struct circ_buf *xmit = &dport->port.info->xmit;
unsigned char tmp;
if (dport->port.x_char) { /* XON/XOFF chars */
dz_out(dport, DZ_TDR, dport->port.x_char);
dport->port.icount.tx++;
dport->port.x_char = 0;
return;
}
/* if nothing to do or stopped or hardware stopped */
if (uart_circ_empty(xmit) || uart_tx_stopped(&dport->port)) {
dz_stop_tx(&dport->port, 0);
return;
}
/*
* if something to do ... (rember the dz has no output fifo so we go
* one char at a time :-<
*/
tmp = xmit->buf[xmit->tail];
xmit->tail = (xmit->tail + 1) & (DZ_XMIT_SIZE - 1);
dz_out(dport, DZ_TDR, tmp);
dport->port.icount.tx++;
if (uart_circ_chars_pending(xmit) < DZ_WAKEUP_CHARS)
uart_write_wakeup(&dport->port);
/* Are we done */
if (uart_circ_empty(xmit))
dz_stop_tx(&dport->port, 0);
}
/*
* ------------------------------------------------------------
* check_modem_status ()
*
* Only valid for the MODEM line duh !
* ------------------------------------------------------------
*/
static inline void check_modem_status(struct dz_port *dport)
{
unsigned short status;
/* if not ne modem line just return */
if (dport->port.line != DZ_MODEM)
return;
status = dz_in(dport, DZ_MSR);
/* it's easy, since DSR2 is the only bit in the register */
if (status)
dport->port.icount.dsr++;
}
