patch-2.3.9 linux/drivers/char/dz.c

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diff -u --recursive --new-file v2.3.8/linux/drivers/char/dz.c linux/drivers/char/dz.c
@@ -0,0 +1,1602 @@
+/*
+ * dz.c: Serial port driver for DECStations equiped 
+ *       with the DZ chipset.
+ *
+ * Copyright (C) 1998 Olivier A. D. Lebaillif 
+ *             
+ * Email: olivier.lebaillif@ifrsys.com
+ *
+ * [31-AUG-98] triemer
+ * Changed IRQ to use Harald's dec internals interrupts.h
+ * removed base_addr code - moving address assignment to setup.c
+ * Changed name of dz_init to rs_init to be consistent with tc code
+ * [13-NOV-98] triemer fixed code to receive characters
+ *    after patches by harald to irq code.  
+ * [09-JAN-99] triemer minor fix for schedule - due to removal of timeout
+ *            field from "current" - somewhere between 2.1.121 and 2.1.131
+ */
+
+#ifdef MODULE
+#include <linux/module.h>
+#include <linux/version.h>
+#else
+#define MOD_INC_USE_COUNT
+#define MOD_DEC_USE_COUNT
+#endif
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/init.h> 
+#include <linux/malloc.h>
+#include <linux/mm.h>
+#include <linux/major.h>
+#include <linux/param.h>
+#include <linux/tqueue.h>
+#include <linux/interrupt.h>
+#include <asm-mips/wbflush.h>
+/* for definition of SERIAL */
+#include <asm/dec/interrupts.h>
+
+/* for definition of struct console */
+#ifdef CONFIG_SERIAL_CONSOLE
+#define CONSOLE_LINE (3)
+#include <linux/console.h>
+#endif /* ifdef CONFIG_SERIAL_CONSOLE */
+
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+
+#include <asm/uaccess.h>
+#include <asm/irq.h>
+#include <asm/dec/machtype.h>
+#include <asm/dec/kn01.h>
+#include <asm/dec/kn02.h>
+
+#define DEBUG_DZ 1
+#ifdef DEBUG_DZ
+#include <linux/tty.h>
+#include <linux/major.h>
+#include <linux/ptrace.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/fs.h>
+#include <asm/bootinfo.h>
+
+extern int (*prom_printf) (char *,...);
+#endif
+
+
+
+#include "dz.h"
+
+#define DZ_INTR_DEBUG 1
+
+DECLARE_TASK_QUEUE(tq_serial);
+
+extern struct wait_queue *keypress_wait;
+static struct dz_serial *lines[4];
+static unsigned char tmp_buffer[256];
+
+
+
+#ifdef DEBUG_DZ
+/*
+ * debugging code to send out chars via prom 
+ */
+static void debug_console( const char *s,int count)
+{
+    unsigned i;
+
+    for (i = 0; i < count; i++) {
+       if (*s == 10)
+           prom_printf("%c", 13);
+       prom_printf("%c", *s++);
+    }
+}
+#endif
+
+/*
+ * ------------------------------------------------------------
+ * dz_in () and dz_out ()
+ *
+ * These routines are used to access the registers of the DZ 
+ * chip, hiding relocation differences between implementation.
+ * ------------------------------------------------------------
+ */
+
+static inline unsigned short dz_in (struct dz_serial *info, unsigned offset)
+{
+  volatile unsigned short *addr = (volatile unsigned short *)(info->port + offset);
+  return *addr;
+}
+
+static inline void dz_out (struct dz_serial *info, unsigned offset, unsigned short value)
+{
+
+    volatile unsigned short *addr = (volatile unsigned short *)(info->port + offset);
+  *addr = value;
+
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_stop () and rs_start ()
+ *
+ * These routines are called before setting or resetting 
+ * tty->stopped. They enable or disable transmitter interrupts, 
+ * as necessary.
+ * ------------------------------------------------------------
+ */
+
+static void dz_stop (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;                   /* clear the TX flag */
+    dz_out (info, DZ_TCR, tmp);
+}  
+
+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);
+
+}  
+
+/*
+ * ------------------------------------------------------------
+ * Here starts the interrupt handling routines.  All of the 
+ * following subroutines are declared as inline and are folded 
+ * into dz_interrupt.  They were separated out for readability's 
+ * sake. 
+ *
+ * Note: rs_interrupt() is a "fast" interrupt, which means that it
+ * runs with interrupts turned off.  People who may want to modify
+ * rs_interrupt() should try to keep the interrupt handler as fast as
+ * possible.  After you are done making modifications, it is not a bad
+ * idea to do:
+ * 
+ * gcc -S -DKERNEL -Wall -Wstrict-prototypes -O6 -fomit-frame-pointer dz.c
+ *
+ * and look at the resulting assemble code in serial.s.
+ *
+ * ------------------------------------------------------------
+ */
+
+/*
+ * ------------------------------------------------------------
+ * dz_sched_event ()
+ *
+ * This routine is used by the interrupt handler to schedule
+ * processing in the software interrupt portion of the driver.
+ * ------------------------------------------------------------
+ */
+static inline void dz_sched_event (struct dz_serial *info, int event)
+{
+  info->event |= 1 << event;
+  queue_task (&info->tqueue, &tq_serial);
+  mark_bh (SERIAL_BH);
+}
+
+/*
+ * ------------------------------------------------------------
+ * receive_char ()
+ *
+ * This routine deals with inputs from any lines.
+ * ------------------------------------------------------------
+ */
+static inline void receive_chars (struct dz_serial *info_in)
+{
+
+  struct dz_serial *info;
+  struct tty_struct *tty = 0;
+  struct async_icount *icount;
+  int ignore = 0;
+  unsigned short status, tmp;
+  unsigned char ch;
+
+  /* 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 (info_in, DZ_RBUF);
+      info = lines[LINE(status)];
+
+      /* punt so we don't get duplicate characters */
+      if (!(status & DZ_DVAL))
+        goto ignore_char;
+
+
+    ch = UCHAR(status);                /* grab the char */
+
+#ifdef 0
+    if (info->is_console) {
+      if (ch == 0) return;            /* it's a break ... */
+
+      wake_up (&keypress_wait);       /* It is a 'keyboard interrupt' ;-) */
+    }
+#endif
+
+    tty = info->tty;                  /* now tty points to the proper dev */
+    icount = &info->icount;
+
+    if (!tty) break;
+    if (tty->flip.count >= TTY_FLIPBUF_SIZE) break;
+
+    *tty->flip.char_buf_ptr = ch;
+    *tty->flip.flag_buf_ptr = 0;
+    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 & info->ignore_status_mask) {
+        if (++ignore > 100 ) break;
+        goto ignore_char;
+      }
+
+      /* mask off the error conditions we want to ignore */
+      tmp = status & info->read_status_mask;
+
+      if (tmp & DZ_PERR)
+	{
+        *tty->flip.flag_buf_ptr = TTY_PARITY;
+	  debug_console("PERR\n",5);
+	}
+      else if (tmp & DZ_FERR)
+	{
+        *tty->flip.flag_buf_ptr = TTY_FRAME;
+	  debug_console("FERR\n",5);
+	}
+      if (tmp & DZ_OERR) 
+	{ 
+	  debug_console("OERR\n",5);
+	if (tty->flip.count < TTY_FLIPBUF_SIZE) {
+          tty->flip.count++;
+          tty->flip.flag_buf_ptr++;
+          tty->flip.char_buf_ptr++;
+          *tty->flip.flag_buf_ptr = TTY_OVERRUN;
+        }
+      }
+    }
+    tty->flip.flag_buf_ptr++;
+    tty->flip.char_buf_ptr++;
+    tty->flip.count++;
+  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 transmit_chars (struct dz_serial *info)
+{
+  unsigned char tmp;
+
+
+
+  if (info->x_char) {           /* XON/XOFF chars */
+    dz_out (info, DZ_TDR, info->x_char);
+    info->icount.tx++;
+    info->x_char = 0;
+    return;
+  }
+
+  /* if nothing to do or stopped or hardware stopped */
+  if ((info->xmit_cnt <= 0) || info->tty->stopped || info->tty->hw_stopped) {
+    dz_stop (info->tty);
+    return;
+  }
+
+  /* if something to do ... (rember the dz has no output fifo so we go one char at a time :-< */
+  tmp = (unsigned short)info->xmit_buf[info->xmit_tail++];
+  dz_out (info, DZ_TDR, tmp);
+  info->xmit_tail = info->xmit_tail & (DZ_XMIT_SIZE - 1);
+  info->icount.tx++;
+
+  if (--info->xmit_cnt < WAKEUP_CHARS)
+    dz_sched_event (info, DZ_EVENT_WRITE_WAKEUP);
+
+
+  /* Are we done */
+  if (info->xmit_cnt <= 0) dz_stop (info->tty);
+}
+
+/*
+ * ------------------------------------------------------------
+ * 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++;
+}
+
+/*
+ * ------------------------------------------------------------
+ * 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;
+
+  status = dz_in ((struct dz_serial *)dev, DZ_CSR); /* get the reason why we just got an irq */
+  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);
+}
+
+/*
+ * -------------------------------------------------------------------
+ * Here ends the DZ interrupt routines.
+ * -------------------------------------------------------------------
+ */
+
+/*
+ * This routine is used to handle the "bottom half" processing for the
+ * serial driver, known also the "software interrupt" processing.
+ * This processing is done at the kernel interrupt level, after the
+ * rs_interrupt() has returned, BUT WITH INTERRUPTS TURNED ON.  This
+ * is where time-consuming activities which can not be done in the
+ * interrupt driver proper are done; the interrupt driver schedules
+ * them using rs_sched_event(), and they get done here.
+ */
+static void do_serial_bh (void)
+{
+        run_task_queue (&tq_serial);
+}
+
+static void do_softint (void *private_data)
+{
+  struct dz_serial *info = (struct dz_serial *)private_data;
+  struct tty_struct *tty = info->tty;
+
+  if (!tty) return;
+
+  if (test_and_clear_bit (DZ_EVENT_WRITE_WAKEUP, &info->event)) {
+    if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup)
+      (tty->ldisc.write_wakeup) (tty);
+    wake_up_interruptible (&tty->write_wait);
+  }
+}
+
+/*
+ * -------------------------------------------------------------------
+ * This routine is called from the scheduler tqueue when the interrupt
+ * routine has signalled that a hangup has occurred.  The path of
+ * hangup processing is:
+ *
+ *      serial interrupt routine -> (scheduler tqueue) ->
+ *      do_serial_hangup() -> tty->hangup() -> rs_hangup()
+ * ------------------------------------------------------------------- 
+ */
+static void do_serial_hangup (void *private_data)
+{
+  struct dz_serial *info = (struct dz_serial *)private_data;
+  struct tty_struct *tty = info->tty;;
+        
+  if (!tty) return;
+
+  tty_hangup (tty);
+}
+
+/*
+ * -------------------------------------------------------------------
+ * 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;
+}
+
+/* 
+ * -------------------------------------------------------------------
+ * 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);
+}
+
+/* 
+ * -------------------------------------------------------------------
+ * change_speed ()
+ *
+ * set the baud rate.
+ * ------------------------------------------------------------------- 
+ */
+static void change_speed (struct dz_serial *info)
+{
+  unsigned long flags;
+  unsigned cflag;
+  int baud;
+
+  if (!info->tty || !info->tty->termios) return;
+  
+  save_flags (flags);
+  cli ();
+  
+  info->cflags = info->line;
+
+  cflag = info->tty->termios->c_cflag;
+
+  switch (cflag & CSIZE) {
+  case CS5: info->cflags |= DZ_CS5; break;
+  case CS6: info->cflags |= DZ_CS6; break;
+  case CS7: info->cflags |= DZ_CS7; break;
+  case CS8: 
+  default:  info->cflags |= DZ_CS8;
+  }
+
+  if (cflag & CSTOPB) info->cflags |= DZ_CSTOPB;
+  if (cflag & PARENB) info->cflags |= DZ_PARENB;
+  if (cflag & PARODD) info->cflags |= DZ_PARODD;
+  
+  baud = tty_get_baud_rate (info->tty);
+  switch (baud) {
+  case 50  :  info->cflags |= DZ_B50;   break;
+  case 75  :  info->cflags |= DZ_B75;   break;
+  case 110 :  info->cflags |= DZ_B110;  break;
+  case 134 :  info->cflags |= DZ_B134;  break; 
+  case 150 :  info->cflags |= DZ_B150;  break;
+  case 300 :  info->cflags |= DZ_B300;  break; 
+  case 600 :  info->cflags |= DZ_B600;  break;
+  case 1200:  info->cflags |= DZ_B1200; break; 
+  case 1800:  info->cflags |= DZ_B1800; break;
+  case 2000:  info->cflags |= DZ_B2000; break;
+  case 2400:  info->cflags |= DZ_B2400; break;
+  case 3600:  info->cflags |= DZ_B3600; break; 
+  case 4800:  info->cflags |= DZ_B4800; break;
+  case 7200:  info->cflags |= DZ_B7200; break; 
+  case 9600: 
+  default  :  info->cflags |= DZ_B9600; 
+  }
+
+  info->cflags |= DZ_RXENAB;
+  dz_out (info, DZ_LPR, info->cflags);
+
+  /* setup accept flag */
+  info->read_status_mask = DZ_OERR;
+  if (I_INPCK(info->tty))
+   info->read_status_mask |= (DZ_FERR | DZ_PERR); 
+  
+  /* characters to ignore */
+  info->ignore_status_mask = 0;
+  if (I_IGNPAR(info->tty))
+    info->ignore_status_mask |= (DZ_FERR | DZ_PERR);
+
+  restore_flags (flags);
+}
+
+/* 
+ * -------------------------------------------------------------------
+ * dz_flush_char ()
+ *
+ * Flush the buffer.
+ * ------------------------------------------------------------------- 
+ */
+static void dz_flush_chars (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+  unsigned long flags;
+
+ if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped || !info->xmit_buf)
+    return;
+
+ save_flags (flags);
+ cli ();  
+
+ dz_start (info->tty);
+
+ restore_flags (flags);
+}
+
+
+/* 
+ * -------------------------------------------------------------------
+ * dz_write ()
+ *
+ * main output routine.
+ * ------------------------------------------------------------------- 
+ */
+static int dz_write (struct tty_struct *tty, int from_user, const unsigned char *buf, int count)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+  unsigned long flags;
+  int c, ret = 0;
+
+  if (!tty ) return ret;
+  if (!info->xmit_buf) return ret;
+  if (!tmp_buf) tmp_buf = tmp_buffer;
+
+
+
+  if (from_user) {
+
+    down (&tmp_buf_sem);
+    while (1) {
+      c = MIN(count, MIN(DZ_XMIT_SIZE - info->xmit_cnt - 1, DZ_XMIT_SIZE - info->xmit_head));
+      if (c <= 0) break;
+
+      c -= copy_from_user (tmp_buf, buf, c);
+      if (!c) {
+        if (!ret) ret = -EFAULT;
+        break;
+      }
+
+      save_flags (flags);
+      cli ();
+
+      c = MIN(c, MIN(DZ_XMIT_SIZE - info->xmit_cnt - 1, DZ_XMIT_SIZE - info->xmit_head));
+      memcpy(info->xmit_buf + info->xmit_head, tmp_buf, c);
+      info->xmit_head = ((info->xmit_head + c) & (DZ_XMIT_SIZE-1));
+      info->xmit_cnt += c;
+
+      restore_flags(flags);
+
+      buf += c;
+      count -= c;
+      ret += c;
+    }
+    
+    up (&tmp_buf_sem);
+  } else {
+
+
+    while (1) {
+      save_flags (flags);
+      cli ();     
+
+      c = MIN(count, MIN(DZ_XMIT_SIZE - info->xmit_cnt - 1, DZ_XMIT_SIZE - info->xmit_head));
+      if (c <= 0) {
+        restore_flags (flags);
+        break;
+      }
+      memcpy (info->xmit_buf + info->xmit_head, buf, c);
+      info->xmit_head = ((info->xmit_head + c) & (DZ_XMIT_SIZE-1));
+      info->xmit_cnt += c;
+
+      restore_flags (flags);
+
+      buf += c;
+      count -= c;
+      ret += c;
+    }
+  }
+
+
+  if (info->xmit_cnt)
+    {
+      if (!tty->stopped) 
+	{
+	  if (!tty->hw_stopped)
+	    {
+	      dz_start (info->tty);
+	    }
+	}
+    }
+  return ret;
+}
+
+/* 
+ * -------------------------------------------------------------------
+ * dz_write_room ()
+ *
+ * compute the amount of space available for writing.
+ * ------------------------------------------------------------------- 
+ */
+static int dz_write_room (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+  int ret;
+                                
+  ret = DZ_XMIT_SIZE - info->xmit_cnt - 1;
+  if (ret < 0) ret = 0;
+  return ret;
+}
+
+/* 
+ * -------------------------------------------------------------------
+ * dz_chars_in_buffer ()
+ *
+ * compute the amount of char left to be transmitted
+ * ------------------------------------------------------------------- 
+ */
+static int dz_chars_in_buffer (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+  
+  return info->xmit_cnt;
+}
+
+/* 
+ * -------------------------------------------------------------------
+ * dz_flush_buffer ()
+ *
+ * Empty the output buffer
+ * ------------------------------------------------------------------- 
+ */
+static void dz_flush_buffer (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+                                
+  cli ();
+  info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
+  sti ();
+
+  wake_up_interruptible (&tty->write_wait);
+
+  if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup)
+    (tty->ldisc.write_wakeup)(tty);
+}
+
+/*
+ * ------------------------------------------------------------
+ * dz_throttle () and dz_unthrottle ()
+ * 
+ * This routine is called by the upper-layer tty layer to signal that
+ * incoming characters should be throttled (or not).
+ * ------------------------------------------------------------
+ */
+static void dz_throttle (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;  
+
+  if (I_IXOFF(tty))
+    info->x_char = STOP_CHAR(tty);
+}
+
+static void dz_unthrottle (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;  
+
+  if (I_IXOFF(tty)) {
+    if (info->x_char)
+      info->x_char = 0;
+    else
+      info->x_char = START_CHAR(tty);
+  }
+}
+
+static void dz_send_xchar (struct tty_struct *tty, char ch)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+
+  info->x_char = ch;
+
+  if (ch) dz_start (info->tty);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_ioctl () and friends
+ * ------------------------------------------------------------
+ */
+static int get_serial_info (struct dz_serial *info, struct serial_struct *retinfo)
+{
+  struct serial_struct tmp;
+  
+  if (!retinfo)
+    return -EFAULT;
+
+  memset (&tmp, 0, sizeof(tmp));
+
+  tmp.type = info->type;
+  tmp.line = info->line;
+  tmp.port = info->port;
+  tmp.irq = SERIAL;
+  tmp.flags = info->flags;
+  tmp.baud_base = info->baud_base;
+  tmp.close_delay = info->close_delay;
+  tmp.closing_wait = info->closing_wait;
+  
+  return copy_to_user (retinfo, &tmp, sizeof(*retinfo));
+}
+
+static int set_serial_info (struct dz_serial *info, struct serial_struct *new_info)
+{
+  struct serial_struct new_serial;
+  struct dz_serial old_info;
+  int retval = 0;
+
+  if (!new_info)
+    return -EFAULT;
+
+  copy_from_user (&new_serial, new_info, sizeof(new_serial));
+  old_info = *info;
+
+  if (!suser())
+    return -EPERM;
+
+  if (info->count > 1)
+    return -EBUSY;
+
+  /*
+   * OK, past this point, all the error checking has been done.
+   * At this point, we start making changes.....
+   */
+  
+  info->baud_base = new_serial.baud_base;
+  info->type = new_serial.type;
+  info->close_delay = new_serial.close_delay;
+  info->closing_wait = new_serial.closing_wait;
+
+  retval = startup (info);
+  return retval;
+}
+
+/*
+ * 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);
+}
+
+/*
+ * 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(jiffies + duration);
+  
+  tmp &= ~mask;
+  dz_out (info, DZ_TCR, tmp);
+  
+  restore_flags (flags);
+}
+
+static int dz_ioctl (struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg)
+{
+  int error;
+  struct dz_serial * info = (struct dz_serial *)tty->driver_data;
+  int retval;
+
+  if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
+      (cmd != TIOCSERCONFIG) && (cmd != TIOCSERGWILD)  &&
+      (cmd != TIOCSERSWILD) && (cmd != TIOCSERGSTRUCT)) {
+    if (tty->flags & (1 << TTY_IO_ERROR))
+      return -EIO;
+  }
+
+  switch (cmd) {
+  case TCSBRK:    /* SVID version: non-zero arg --> no break */
+    retval = tty_check_change (tty);
+    if (retval)
+      return retval;
+    tty_wait_until_sent (tty, 0);
+    if (!arg)
+      send_break (info, HZ/4); /* 1/4 second */
+    return 0;
+
+  case TCSBRKP:   /* support for POSIX tcsendbreak() */
+    retval = tty_check_change (tty);
+    if (retval)
+      return retval;
+    tty_wait_until_sent (tty, 0);
+    send_break (info, arg ? arg*(HZ/10) : HZ/4);
+    return 0;
+
+  case TIOCGSOFTCAR:
+    error = verify_area (VERIFY_WRITE, (void *)arg, sizeof(long));
+    if (error)
+      return error;
+    put_user (C_CLOCAL(tty) ? 1 : 0, (unsigned long *)arg);
+    return 0;
+
+  case TIOCSSOFTCAR:
+    error = get_user (arg, (unsigned long *)arg);
+    if (error)
+      return error;
+    tty->termios->c_cflag = ((tty->termios->c_cflag & ~CLOCAL) | (arg ? CLOCAL : 0));
+    return 0;
+
+  case TIOCGSERIAL:
+    error = verify_area (VERIFY_WRITE, (void *)arg, sizeof(struct serial_struct));
+    if (error)
+      return error;
+    return get_serial_info (info, (struct serial_struct *)arg);
+
+  case TIOCSSERIAL:
+    return set_serial_info (info, (struct serial_struct *) arg);
+
+  case TIOCSERGETLSR: /* Get line status register */
+    error = verify_area (VERIFY_WRITE, (void *)arg, sizeof(unsigned int));
+    if (error)
+      return error;
+    else
+      return get_lsr_info (info, (unsigned int *)arg);
+
+  case TIOCSERGSTRUCT:
+    error = verify_area (VERIFY_WRITE, (void *)arg, sizeof(struct dz_serial));
+    if (error)
+      return error;
+    copy_to_user((struct dz_serial *)arg, info, sizeof(struct dz_serial));
+    return 0;
+    
+  default:
+    return -ENOIOCTLCMD;
+  }
+
+  return 0;
+}
+
+static void dz_set_termios (struct tty_struct *tty,
+			    struct termios *old_termios)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+
+  if (tty->termios->c_cflag == old_termios->c_cflag)
+    return;
+
+  change_speed (info);
+
+  if ((old_termios->c_cflag & CRTSCTS) &&
+      !(tty->termios->c_cflag & CRTSCTS)) {
+    tty->hw_stopped = 0;
+    dz_start (tty);
+  }
+}
+
+/*
+ * ------------------------------------------------------------
+ * dz_close()
+ * 
+ * This routine is called when the serial port gets closed.  First, we
+ * wait for the last remaining data to be sent.  Then, we turn off
+ * the transmit enable and receive enable flags.
+ * ------------------------------------------------------------
+ */
+static void dz_close (struct tty_struct *tty, struct file *filp)
+{
+  struct dz_serial * info = (struct dz_serial *)tty->driver_data;
+  unsigned long flags;
+
+  if (!info) 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("dz_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 |= DZ_CLOSING;
+  /*
+   * Save the termios structure, since this port may have
+   * separate termios for callout and dialin.
+   */
+  if (info->flags & DZ_NORMAL_ACTIVE)
+    info->normal_termios = *tty->termios;
+  if (info->flags & DZ_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 != DZ_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.
+   */
+
+  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 != 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);
+  }
+  if (info->blocked_open) {
+    if (info->close_delay) {
+      current->state = TASK_INTERRUPTIBLE;
+      schedule_timeout(jiffies + info->close_delay);
+    }
+    wake_up_interruptible (&info->open_wait);
+  }
+
+  info->flags &= ~(DZ_NORMAL_ACTIVE | DZ_CALLOUT_ACTIVE | DZ_CLOSING);
+  wake_up_interruptible (&info->close_wait);
+
+  restore_flags (flags);
+}
+
+/*
+ * dz_hangup () --- called by tty_hangup() when a hangup is signaled.
+ */
+static void dz_hangup (struct tty_struct *tty)
+{
+  struct dz_serial *info = (struct dz_serial *)tty->driver_data;
+  
+  dz_flush_buffer (tty);
+  shutdown (info);
+  info->event = 0;
+  info->count = 0;
+  info->flags &= ~(DZ_NORMAL_ACTIVE | DZ_CALLOUT_ACTIVE);
+  info->tty = 0;
+  wake_up_interruptible (&info->open_wait);
+}
+
+/*
+ * ------------------------------------------------------------
+ * rs_open() and friends
+ * ------------------------------------------------------------
+ */
+static int block_til_ready (struct tty_struct *tty, struct file *filp, struct dz_serial *info)
+{
+  struct wait_queue wait = { current, NULL };
+  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 & DZ_CLOSING) {
+    interruptible_sleep_on (&info->close_wait);
+    return -EAGAIN;
+  }
+
+  /*
+   * 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 & DZ_NORMAL_ACTIVE)
+      return -EBUSY;
+    
+    if ((info->flags & DZ_CALLOUT_ACTIVE) &&
+	(info->flags & DZ_SESSION_LOCKOUT) &&
+	(info->session != current->session))
+      return -EBUSY;
+    
+    if ((info->flags & DZ_CALLOUT_ACTIVE) &&
+	(info->flags & DZ_PGRP_LOCKOUT) &&
+	(info->pgrp != current->pgrp))
+      return -EBUSY;
+    info->flags |= DZ_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 & DZ_CALLOUT_ACTIVE)
+      return -EBUSY;
+    info->flags |= DZ_NORMAL_ACTIVE;
+    return 0;
+  }
+
+  if (info->flags & DZ_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
+   * dz_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) {
+    current->state = TASK_INTERRUPTIBLE;
+    if (tty_hung_up_p (filp) || !(info->is_initialized)) {
+      retval = -EAGAIN;
+      break;
+    }
+    if (!(info->flags & DZ_CALLOUT_ACTIVE) &&
+	!(info->flags & DZ_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 |= DZ_NORMAL_ACTIVE;
+  return 0;
+}       
+
+/*
+ * This routine is called whenever a serial port is opened.  It
+ * enables interrupts for a serial port. It also performs the 
+ * serial-specific initialization for the tty structure.
+ */
+static int dz_open (struct tty_struct *tty, struct file *filp)
+{
+  struct dz_serial *info;
+  int retval, line;
+
+  line = MINOR(tty->device) - tty->driver.minor_start;
+
+  /* The dz lines for the mouse/keyboard must be
+   * opened using their respective drivers.
+   */
+  if ((line < 0) || (line >= DZ_NB_PORT))
+    return -ENODEV;
+
+  if ((line == DZ_KEYBOARD) || (line == DZ_MOUSE))
+    return -ENODEV;
+
+  info = lines[line];
+  info->count++;
+
+  tty->driver_data = info;
+  info->tty = tty;
+
+  /*
+   * Start up serial port
+   */
+  retval = startup (info);
+  if (retval)
+    return retval;
+
+
+
+  retval = block_til_ready (tty, filp, info);
+  if (retval)
+    return retval;
+
+  if ((info->count == 1) && (info->flags & DZ_SPLIT_TERMIOS)) {
+    if (tty->driver.subtype == SERIAL_TYPE_NORMAL)
+      *tty->termios = info->normal_termios;
+    else 
+      *tty->termios = info->callout_termios;
+    change_speed (info);
+
+  }
+
+  info->session = current->session;
+  info->pgrp = current->pgrp;
+  return 0;
+}
+
+static void show_serial_version (void)
+{
+  printk("%s%s\n", dz_name, dz_version);
+}
+
+
+__initfunc(int dz_init(void))
+{
+  int i, flags;
+  struct dz_serial *info;
+
+  /* Setup base handler, and timer table. */
+  init_bh (SERIAL_BH, do_serial_bh);
+
+  show_serial_version ();
+
+  memset(&serial_driver, 0, sizeof(struct tty_driver));
+  serial_driver.magic = TTY_DRIVER_MAGIC;
+  serial_driver.name = "ttyS";
+  serial_driver.major = TTY_MAJOR;
+  serial_driver.minor_start = 64;
+  serial_driver.num = DZ_NB_PORT;
+  serial_driver.type = TTY_DRIVER_TYPE_SERIAL;
+  serial_driver.subtype = SERIAL_TYPE_NORMAL;
+  serial_driver.init_termios = tty_std_termios;
+
+  serial_driver.init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+  serial_driver.flags = TTY_DRIVER_REAL_RAW;
+  serial_driver.refcount = &serial_refcount;
+  serial_driver.table = serial_table;
+  serial_driver.termios = serial_termios;
+  serial_driver.termios_locked = serial_termios_locked;
+
+  serial_driver.open = dz_open;
+  serial_driver.close = dz_close;
+  serial_driver.write = dz_write;
+  serial_driver.flush_chars = dz_flush_chars;
+  serial_driver.write_room = dz_write_room;
+  serial_driver.chars_in_buffer = dz_chars_in_buffer;
+  serial_driver.flush_buffer = dz_flush_buffer;
+  serial_driver.ioctl = dz_ioctl;
+  serial_driver.throttle = dz_throttle;
+  serial_driver.unthrottle = dz_unthrottle;
+  serial_driver.send_xchar = dz_send_xchar;
+  serial_driver.set_termios = dz_set_termios;
+  serial_driver.stop = dz_stop;
+  serial_driver.start = dz_start;
+  serial_driver.hangup = dz_hangup;
+
+  /*
+   * The callout device is just like normal device except for
+   * major number and the subtype code.
+   */
+  callout_driver = serial_driver;
+  callout_driver.name = "cua";
+  callout_driver.major = TTYAUX_MAJOR;
+  callout_driver.subtype = SERIAL_TYPE_CALLOUT;
+
+  if (tty_register_driver (&serial_driver))
+    panic("Couldn't register serial driver\n");
+  if (tty_register_driver (&callout_driver))
+    panic("Couldn't register callout driver\n");
+  save_flags(flags); cli();
+ 
+  i = 0;
+  for (info = &multi[i]; i < DZ_NB_PORT;  i++) 
+    {
+      lines[i] = info;
+    info->magic = SERIAL_MAGIC;
+
+      if ((mips_machtype == MACH_DS23100) || (mips_machtype == MACH_DS5100)) 
+      info->port = (unsigned long) KN01_DZ11_BASE;
+      else 
+      info->port = (unsigned long) KN02_DZ11_BASE;
+
+    info->line = i;
+    info->tty = 0;
+    info->close_delay = 50;
+    info->closing_wait = 3000;
+    info->x_char = 0;
+    info->event = 0;
+    info->count = 0;
+    info->blocked_open = 0;
+    info->tqueue.routine = do_softint;
+    info->tqueue.data = info;
+    info->tqueue_hangup.routine = do_serial_hangup;
+    info->tqueue_hangup.data = info;
+    info->callout_termios = callout_driver.init_termios;
+    info->normal_termios = serial_driver.init_termios;
+    info->open_wait = 0;
+    info->close_wait = 0;
+
+    /* If we are pointing to address zero then punt - not correctly
+       set up in setup.c to handle this. */
+    if (! info->port)
+      return 0;
+
+    printk("ttyS%02d at 0x%04x (irq = %d)\n", info->line, info->port, SERIAL);
+  }
+
+  /* reset the chip */
+#ifndef CONFIG_SERIAL_CONSOLE
+  dz_out(info, DZ_CSR, DZ_CLR);
+  while ((tmp = dz_in(info,DZ_CSR)) & DZ_CLR) ;
+  wbflush();
+  
+  /* enable scanning */
+   dz_out(info, DZ_CSR, DZ_MSE); 
+#endif
+  
+  /* order matters here... the trick is that flags
+     is updated... in request_irq - to immediatedly obliterate
+     it is unwise. */
+  restore_flags(flags);
+ 
+
+  if (request_irq (SERIAL, dz_interrupt, SA_INTERRUPT, "DZ", lines[0]))
+    panic ("Unable to register DZ interrupt\n");
+ 
+  return 0;
+}
+
+#ifdef CONFIG_SERIAL_CONSOLE
+static void dz_console_put_char (unsigned char ch)
+{
+  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_TCR) & DZ_TRDY) != DZ_TRDY) &&  loops--)
+    ;
+  
+  /* Actually transmit the character. */
+  dz_out (dz_console, DZ_TDR, tmp);
+
+  restore_flags(flags); 
+}
+/* 
+ * -------------------------------------------------------------------
+ * dz_console_print ()
+ *
+ * dz_console_print is registered for printk.
+ * ------------------------------------------------------------------- 
+ */
+static void dz_console_print (struct console *cons, 
+			      const char *str, 
+			      unsigned int count)
+{
+#ifdef DEBUG_DZ
+  prom_printf((char *)str);
+#endif
+  while (count--) 
+    {
+    if (*str == '\n')
+	dz_console_put_char ('\r');
+      dz_console_put_char (*str++);
+  }
+}
+
+static int dz_console_wait_key(struct console *co)
+{
+    return 0;
+}
+
+static kdev_t dz_console_device(struct console *c)
+{
+	return MKDEV(TTY_MAJOR, 64 + c->index);
+}
+
+__initfunc(static int dz_console_setup(struct console *co, char *options))
+{
+  	int	baud = 9600;
+	int	bits = 8;
+	int	parity = 'n';
+	int	cflag = CREAD | HUPCL | CLOCAL;
+	char	*s;
+	unsigned short mask,tmp;
+
+	if (options) {
+		baud = simple_strtoul(options, NULL, 10);
+		s = options;
+		while(*s >= '0' && *s <= '9')
+			s++;
+		if (*s)
+			parity = *s++;
+		if (*s)
+			bits   = *s - '0';
+	}
+
+	/*
+	 *	Now construct a cflag setting.
+	 */
+	switch(baud) {
+	case 1200:
+		cflag |= DZ_B1200;
+		break;
+	case 2400:
+		cflag |= DZ_B2400;
+		break;
+	case 4800:
+		cflag |= DZ_B4800;
+		break;
+	case 9600:
+	default:
+		cflag |= DZ_B9600;
+		break;
+	}
+	switch(bits) {
+	case 7:
+		cflag |= DZ_CS7;
+		break;
+	default:
+	case 8:
+		cflag |= DZ_CS8;
+		break;
+	}
+	switch(parity) {
+	case 'o': case 'O':
+		cflag |= DZ_PARODD;
+		break;
+	case 'e': case 'E':
+		cflag |= DZ_PARENB;
+		break;
+	}
+	co->cflag = cflag;
+
+	/* TOFIX: force to console line */
+	dz_console = &multi[CONSOLE_LINE];
+    	if ((mips_machtype == MACH_DS23100) || (mips_machtype == MACH_DS5100)) 
+	dz_console->port = KN01_DZ11_BASE;
+       	else 
+       		dz_console->port = KN02_DZ11_BASE; 
+	dz_console->line = CONSOLE_LINE;
+
+	dz_out(dz_console, DZ_CSR, DZ_CLR);
+	while ((tmp = dz_in(dz_console,DZ_CSR)) & DZ_CLR)
+	  ;
+
+	/* enable scanning */
+	dz_out(dz_console, DZ_CSR, DZ_MSE); 
+
+        /*  Set up flags... */
+	dz_console->cflags = 0;
+	dz_console->cflags |= DZ_B9600;
+	dz_console->cflags |= DZ_CS8;
+	dz_console->cflags |= DZ_PARENB;
+	dz_out (dz_console, DZ_LPR, dz_console->cflags);
+
+
+	mask = 1 << dz_console->line;
+	tmp = dz_in (dz_console, DZ_TCR);       /* read the TX flag */
+	if (!(tmp & mask)) {
+	  tmp |= mask;                   /* set the TX flag */
+	  dz_out (dz_console, DZ_TCR, tmp); 
+	}
+	
+
+	/* TOFIX: force to console line */
+	dz_console = &multi[CONSOLE_LINE];
+    	if ((mips_machtype == MACH_DS23100) || (mips_machtype == MACH_DS5100)) 
+	dz_console->port = KN01_DZ11_BASE;
+       	else 
+       		dz_console->port = KN02_DZ11_BASE; 
+	dz_console->line = CONSOLE_LINE;
+
+	dz_out(dz_console, DZ_CSR, DZ_CLR);
+	while ((tmp = dz_in(dz_console,DZ_CSR)) & DZ_CLR)
+	  ;
+
+	/* enable scanning */
+	dz_out(dz_console, DZ_CSR, DZ_MSE); 
+
+        /*  Set up flags... */
+	dz_console->cflags = 0;
+	dz_console->cflags |= DZ_B9600;
+	dz_console->cflags |= DZ_CS8;
+	dz_console->cflags |= DZ_PARENB;
+	dz_out (dz_console, DZ_LPR, dz_console->cflags);
+
+
+	mask = 1 << dz_console->line;
+	tmp = dz_in (dz_console, DZ_TCR);       /* read the TX flag */
+	if (!(tmp & mask)) {
+	  tmp |= mask;                   /* set the TX flag */
+	  dz_out (dz_console, DZ_TCR, tmp); 
+	}
+	
+
+	return 0;
+}
+
+static struct console dz_sercons = {
+	"ttyS",
+	dz_console_print,
+	NULL,
+	dz_console_device,
+	dz_console_wait_key,
+	NULL,
+	dz_console_setup,
+	CON_CONSDEV | CON_PRINTBUFFER,
+	CONSOLE_LINE,
+	0,
+	NULL
+};
+
+__initfunc (long dz_serial_console_init(long kmem_start, long kmem_end))
+{
+	register_console(&dz_sercons);
+
+	return kmem_start;
+}
+
+#endif /* ifdef CONFIG_SERIAL_CONSOLE */
+

FUNET's LINUX-ADM group, linux-adm@nic.funet.fi
TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)