/*

 
	Copyright (C) 1996  Digi International.
 
	For technical support please email digiLinux@dgii.com or
	call Digi tech support at (612) 912-3456

	Much of this design and code came from epca.c which was 
	copyright (C) 1994, 1995 Troy De Jongh, and subsquently 
	modified by David Nugent, Christoph Lameter, Mike McLagan. 
 
 	This program is free software; you can redistribute it and/or modify
 	it under the terms of the GNU General Public License as published by
 	the Free Software Foundation; either version 2 of the License, or
 	(at your option) any later version.

 	This program is distributed in the hope that it will be useful,
 	but WITHOUT ANY WARRANTY; without even the implied warranty of
 	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 	GNU General Public License for more details.

 	You should have received a copy of the GNU General Public License
 	along with this program; if not, write to the Free Software
 	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

--------------------------------------------------------------------------- */
/* See README.epca for change history --DAT*/


#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/serial.h>
#include <linux/delay.h>
#include <linux/ctype.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/slab.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <asm/uaccess.h>
#include <asm/io.h>

#ifdef CONFIG_PCI
#define ENABLE_PCI
#endif /* CONFIG_PCI */

#define putUser(arg1, arg2) put_user(arg1, (unsigned long __user *)arg2)
#define getUser(arg1, arg2) get_user(arg1, (unsigned __user *)arg2)

#ifdef ENABLE_PCI
#include <linux/pci.h>
#include "digiPCI.h"
#endif /* ENABLE_PCI */

#include "digi1.h"
#include "digiFep1.h"
#include "epca.h"
#include "epcaconfig.h"

#if BITS_PER_LONG != 32
#  error FIXME: this driver only works on 32-bit platforms
#endif

/* ---------------------- Begin defines ------------------------ */

#define VERSION            "1.3.0.1-LK"

/* This major needs to be submitted to Linux to join the majors list */

#define DIGIINFOMAJOR       35  /* For Digi specific ioctl */ 


#define MAXCARDS 7
#define epcaassert(x, msg)  if (!(x)) epca_error(__LINE__, msg)

#define PFX "epca: "

/* ----------------- Begin global definitions ------------------- */

static char mesg[100];
static int nbdevs, num_cards, liloconfig;
static int digi_poller_inhibited = 1 ;

static int setup_error_code;
static int invalid_lilo_config;

/* -----------------------------------------------------------------------
	MAXBOARDS is typically 12, but ISA and EISA cards are restricted to 
	7 below.
--------------------------------------------------------------------------*/
static struct board_info boards[MAXBOARDS];


/* ------------- Begin structures used for driver registeration ---------- */

static struct tty_driver *pc_driver;
static struct tty_driver *pc_info;

/* ------------------ Begin Digi specific structures -------------------- */

/* ------------------------------------------------------------------------
	digi_channels represents an array of structures that keep track of
	each channel of the Digi product.  Information such as transmit and
	receive pointers, termio data, and signal definitions (DTR, CTS, etc ...)
	are stored here.  This structure is NOT used to overlay the cards 
	physical channel structure.
-------------------------------------------------------------------------- */
  
static struct channel digi_channels[MAX_ALLOC];

/* ------------------------------------------------------------------------
	card_ptr is an array used to hold the address of the
	first channel structure of each card.  This array will hold
	the addresses of various channels located in digi_channels.
-------------------------------------------------------------------------- */
static struct channel *card_ptr[MAXCARDS];

static struct timer_list epca_timer;

/* ---------------------- Begin function prototypes --------------------- */

/* ----------------------------------------------------------------------
	Begin generic memory functions.  These functions will be alias
	(point at) more specific functions dependent on the board being
	configured.
----------------------------------------------------------------------- */
	
static inline void memwinon(struct board_info *b, unsigned int win);
static inline void memwinoff(struct board_info *b, unsigned int win);
static inline void globalwinon(struct channel *ch);
static inline void rxwinon(struct channel *ch);
static inline void txwinon(struct channel *ch);
static inline void memoff(struct channel *ch);
static inline void assertgwinon(struct channel *ch);
static inline void assertmemoff(struct channel *ch);

/* ---- Begin more 'specific' memory functions for cx_like products --- */

static inline void pcxem_memwinon(struct board_info *b, unsigned int win);
static inline void pcxem_memwinoff(struct board_info *b, unsigned int win);
static inline void pcxem_globalwinon(struct channel *ch);
static inline void pcxem_rxwinon(struct channel *ch);
static inline void pcxem_txwinon(struct channel *ch);
static inline void pcxem_memoff(struct channel *ch);

/* ------ Begin more 'specific' memory functions for the pcxe ------- */

static inline void pcxe_memwinon(struct board_info *b, unsigned int win);
static inline void pcxe_memwinoff(struct board_info *b, unsigned int win);
static inline void pcxe_globalwinon(struct channel *ch);
static inline void pcxe_rxwinon(struct channel *ch);
static inline void pcxe_txwinon(struct channel *ch);
static inline void pcxe_memoff(struct channel *ch);

/* ---- Begin more 'specific' memory functions for the pc64xe and pcxi ---- */
/* Note : pc64xe and pcxi share the same windowing routines */

static inline void pcxi_memwinon(struct board_info *b, unsigned int win);
static inline void pcxi_memwinoff(struct board_info *b, unsigned int win);
static inline void pcxi_globalwinon(struct channel *ch);
static inline void pcxi_rxwinon(struct channel *ch);
static inline void pcxi_txwinon(struct channel *ch);
static inline void pcxi_memoff(struct channel *ch);

/* - Begin 'specific' do nothing memory functions needed for some cards - */

static inline void dummy_memwinon(struct board_info *b, unsigned int win);
static inline void dummy_memwinoff(struct board_info *b, unsigned int win);
static inline void dummy_globalwinon(struct channel *ch);
static inline void dummy_rxwinon(struct channel *ch);
static inline void dummy_txwinon(struct channel *ch);
static inline void dummy_memoff(struct channel *ch);
static inline void dummy_assertgwinon(struct channel *ch);
static inline void dummy_assertmemoff(struct channel *ch);

/* ------------------- Begin declare functions ----------------------- */

static inline struct channel *verifyChannel(register struct tty_struct *);
static inline void pc_sched_event(struct channel *, int);
static void epca_error(int, char *);
static void pc_close(struct tty_struct *, struct file *);
static void shutdown(struct channel *);
static void pc_hangup(struct tty_struct *);
static void pc_put_char(struct tty_struct *, unsigned char);
static int pc_write_room(struct tty_struct *);
static int pc_chars_in_buffer(struct tty_struct *);
static void pc_flush_buffer(struct tty_struct *);
static void pc_flush_chars(struct tty_struct *);
static int block_til_ready(struct tty_struct *, struct file *,
                           struct channel *);
static int pc_open(struct tty_struct *, struct file *);
static void post_fep_init(unsigned int crd);
static void epcapoll(unsigned long);
static void doevent(int);
static void fepcmd(struct channel *, int, int, int, int, int);
static unsigned termios2digi_h(struct channel *ch, unsigned);
static unsigned termios2digi_i(struct channel *ch, unsigned);
static unsigned termios2digi_c(struct channel *ch, unsigned);
static void epcaparam(struct tty_struct *, struct channel *);
static void receive_data(struct channel *);
static int pc_ioctl(struct tty_struct *, struct file *,
                    unsigned int, unsigned long);
static int info_ioctl(struct tty_struct *, struct file *,
                    unsigned int, unsigned long);
static void pc_set_termios(struct tty_struct *, struct termios *);
static void do_softint(void *);
static void pc_stop(struct tty_struct *);
static void pc_start(struct tty_struct *);
static void pc_throttle(struct tty_struct * tty);
static void pc_unthrottle(struct tty_struct *tty);
static void digi_send_break(struct channel *ch, int msec);
static void setup_empty_event(struct tty_struct *tty, struct channel *ch);
void epca_setup(char *, int *);
void console_print(const char *);

static int get_termio(struct tty_struct *, struct termio __user *);
static int pc_write(struct tty_struct *, const unsigned char *, int);
int pc_init(void);

#ifdef ENABLE_PCI
static int init_PCI(void);
#endif /* ENABLE_PCI */


/* ------------------------------------------------------------------
	Table of functions for each board to handle memory.  Mantaining 
	parallelism is a *very* good idea here.  The idea is for the 
	runtime code to blindly call these functions, not knowing/caring    
	about the underlying hardware.  This stuff should contain no
	conditionals; if more functionality is needed a different entry
	should be established.  These calls are the interface calls and 
	are the only functions that should be accessed.  Anyone caught
	making direct calls deserves what they get.
-------------------------------------------------------------------- */

static inline void memwinon(struct board_info *b, unsigned int win)
{
	(b->memwinon)(b, win);
}

static inline void memwinoff(struct board_info *b, unsigned int win)
{
	(b->memwinoff)(b, win);
}

static inline void globalwinon(struct channel *ch)
{
	(ch->board->globalwinon)(ch);
}

static inline void rxwinon(struct channel *ch)
{
	(ch->board->rxwinon)(ch);
}

static inline void txwinon(struct channel *ch)
{
	(ch->board->txwinon)(ch);
}

static inline void memoff(struct channel *ch)
{
	(ch->board->memoff)(ch);
}
static inline void assertgwinon(struct channel *ch)
{
	(ch->board->assertgwinon)(ch);
}

static inline void assertmemoff(struct channel *ch)
{
	(ch->board->assertmemoff)(ch);
}

/* ---------------------------------------------------------
	PCXEM windowing is the same as that used in the PCXR 
	and CX series cards.
------------------------------------------------------------ */

static inline void pcxem_memwinon(struct board_info *b, unsigned int win)
{
        outb_p(FEPWIN|win, (int)b->port + 1);
}

static inline void pcxem_memwinoff(struct board_info *b, unsigned int win)
{
	outb_p(0, (int)b->port + 1);
}

static inline void pcxem_globalwinon(struct channel *ch)
{
	outb_p( FEPWIN, (int)ch->board->port + 1);
}

static inline void pcxem_rxwinon(struct channel *ch)
{
	outb_p(ch->rxwin, (int)ch->board->port + 1);
}

static inline void pcxem_txwinon(struct channel *ch)
{
	outb_p(ch->txwin, (int)ch->board->port + 1);
}

static inline void pcxem_memoff(struct channel *ch)
{
	outb_p(0, (int)ch->board->port + 1);
}

/* ----------------- Begin pcxe memory window stuff ------------------ */

static inline void pcxe_memwinon(struct board_info *b, unsigned int win)
{
               outb_p(FEPWIN | win, (int)b->port + 1);
}

static inline void pcxe_memwinoff(struct board_info *b, unsigned int win)
{
	outb_p(inb((int)b->port) & ~FEPMEM,
	           (int)b->port + 1);
	outb_p(0, (int)b->port + 1);
}

static inline void pcxe_globalwinon(struct channel *ch)
{
	outb_p( FEPWIN, (int)ch->board->port + 1);
}

static inline void pcxe_rxwinon(struct channel *ch)
{
		outb_p(ch->rxwin, (int)ch->board->port + 1);
}

static inline void pcxe_txwinon(struct channel *ch)
{
		outb_p(ch->txwin, (int)ch->board->port + 1);
}

static inline void pcxe_memoff(struct channel *ch)
{
	outb_p(0, (int)ch->board->port);
	outb_p(0, (int)ch->board->port + 1);
}

/* ------------- Begin pc64xe and pcxi memory window stuff -------------- */

static inline void pcxi_memwinon(struct board_info *b, unsigned int win)
{
               outb_p(inb((int)b->port) | FEPMEM, (int)b->port);
}

static inline void pcxi_memwinoff(struct board_info *b, unsigned int win)
{
	outb_p(inb((int)b->port) & ~FEPMEM, (int)b->port);
}

static inline void pcxi_globalwinon(struct channel *ch)
{
	outb_p(FEPMEM, (int)ch->board->port);
}

static inline void pcxi_rxwinon(struct channel *ch)
{
		outb_p(FEPMEM, (int)ch->board->port);
}

static inline void pcxi_txwinon(struct channel *ch)
{
		outb_p(FEPMEM, (int)ch->board->port);
}

static inline void pcxi_memoff(struct channel *ch)
{
	outb_p(0, (int)ch->board->port);
}

static inline void pcxi_assertgwinon(struct channel *ch)
{
	epcaassert(inb((int)ch->board->port) & FEPMEM, "Global memory off");
}

static inline void pcxi_assertmemoff(struct channel *ch)
{
	epcaassert(!(inb((int)ch->board->port) & FEPMEM), "Memory on");
}


/* ----------------------------------------------------------------------
	Not all of the cards need specific memory windowing routines.  Some
	cards (Such as PCI) needs no windowing routines at all.  We provide
	these do nothing routines so that the same code base can be used.
	The driver will ALWAYS call a windowing routine if it thinks it needs
	to; regardless of the card.  However, dependent on the card the routine
	may or may not do anything.
---------------------------------------------------------------------------*/

static inline void dummy_memwinon(struct board_info *b, unsigned int win)
{
}

static inline void dummy_memwinoff(struct board_info *b, unsigned int win)
{
}

static inline void dummy_globalwinon(struct channel *ch)
{
}

static inline void dummy_rxwinon(struct channel *ch)
{
}

static inline void dummy_txwinon(struct channel *ch)
{
}

static inline void dummy_memoff(struct channel *ch)
{
}

static inline void dummy_assertgwinon(struct channel *ch)
{
}

static inline void dummy_assertmemoff(struct channel *ch)
{
}

/* ----------------- Begin verifyChannel function ----------------------- */
static inline struct channel *verifyChannel(register struct tty_struct *tty)
{ /* Begin verifyChannel */

	/* --------------------------------------------------------------------
		This routine basically provides a sanity check.  It insures that
		the channel returned is within the proper range of addresses as
		well as properly initialized.  If some bogus info gets passed in
		through tty->driver_data this should catch it.
	--------------------------------------------------------------------- */

	if (tty) 
	{ /* Begin if tty */

		register struct channel *ch = (struct channel *)tty->driver_data;

		if ((ch >= &digi_channels[0]) && (ch < &digi_channels[nbdevs])) 
		{
			if (ch->magic == EPCA_MAGIC)
				return ch;
		}

	} /* End if tty */

	/* Else return a NULL for invalid */
	return NULL;

} /* End verifyChannel */

/* ------------------ Begin pc_sched_event ------------------------- */

static inline void pc_sched_event(struct channel *ch, int event)
{ /* Begin pc_sched_event */


	/* ----------------------------------------------------------------------
		We call this to schedule interrupt processing on some event.  The 
		kernel sees our request and calls the related routine in OUR driver.
	-------------------------------------------------------------------------*/

	ch->event |= 1 << event;
	schedule_work(&ch->tqueue);


} /* End pc_sched_event */

/* ------------------ Begin epca_error ------------------------- */

static void epca_error(int line, char *msg)
{ /* Begin epca_error */

	printk(KERN_ERR "epca_error (Digi): line = %d %s\n",line,msg);
	return;

} /* End epca_error */

/* ------------------ Begin pc_close ------------------------- */
static void pc_close(struct tty_struct * tty, struct file * filp)
{ /* Begin pc_close */

	struct channel *ch;
	unsigned long flags;

	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) != NULL) 
	{ /* Begin if ch != NULL */

		save_flags(flags);
		cli();

		if (tty_hung_up_p(filp)) 
		{
			restore_flags(flags);
			return;
		}

		/* Check to see if the channel is open more than once */
		if (ch->count-- > 1) 
		{ /* Begin channel is open more than once */

			/* -------------------------------------------------------------
				Return without doing anything.  Someone might still be using
				the channel.
			---------------------------------------------------------------- */

			restore_flags(flags);
			return;
		} /* End channel is open more than once */

		/* Port open only once go ahead with shutdown & reset */

		if (ch->count < 0) 
		{
			ch->count = 0;
		}

		/* ---------------------------------------------------------------
			Let the rest of the driver know the channel is being closed.
			This becomes important if an open is attempted before close 
			is finished.
		------------------------------------------------------------------ */

		ch->asyncflags |= ASYNC_CLOSING;
	
		tty->closing = 1;

		if (ch->asyncflags & ASYNC_INITIALIZED) 
		{
			/* Setup an event to indicate when the transmit buffer empties */
			setup_empty_event(tty, ch);		
			tty_wait_until_sent(tty, 3000); /* 30 seconds timeout */
		}
	
		if (tty->driver->flush_buffer)
			tty->driver->flush_buffer(tty);

		tty_ldisc_flush(tty);
		shutdown(ch);
		tty->closing = 0;
		ch->event = 0;
		ch->tty = NULL;

		if (ch->blocked_open) 
		{ /* Begin if blocked_open */

			if (ch->close_delay) 
			{
				msleep_interruptible(jiffies_to_msecs(ch->close_delay));
			}

			wake_up_interruptible(&ch->open_wait);

		} /* End if blocked_open */

		ch->asyncflags &= ~(ASYNC_NORMAL_ACTIVE | ASYNC_INITIALIZED | 
		                      ASYNC_CLOSING);
		wake_up_interruptible(&ch->close_wait);


		restore_flags(flags);

	} /* End if ch != NULL */

} /* End pc_close */ 

/* ------------------ Begin shutdown  ------------------------- */

static void shutdown(struct channel *ch)
{ /* Begin shutdown */

	unsigned long flags;
	struct tty_struct *tty;
	volatile struct board_chan *bc;

	if (!(ch->asyncflags & ASYNC_INITIALIZED)) 
		return;

	save_flags(flags);
	cli();
	globalwinon(ch);

	bc = ch->brdchan;

	/* ------------------------------------------------------------------
		In order for an event to be generated on the receipt of data the
		idata flag must be set. Since we are shutting down, this is not 
		necessary clear this flag.
	--------------------------------------------------------------------- */ 

	if (bc)
		bc->idata = 0;

	tty = ch->tty;

	/* ----------------------------------------------------------------
	   If we're a modem control device and HUPCL is on, drop RTS & DTR.
 	------------------------------------------------------------------ */

	if (tty->termios->c_cflag & HUPCL) 
	{
		ch->omodem &= ~(ch->m_rts | ch->m_dtr);
		fepcmd(ch, SETMODEM, 0, ch->m_dtr | ch->m_rts, 10, 1);
	}

	memoff(ch);

	/* ------------------------------------------------------------------
		The channel has officialy been closed.  The next time it is opened
		it will have to reinitialized.  Set a flag to indicate this.
	---------------------------------------------------------------------- */

	/* Prevent future Digi programmed interrupts from coming active */

	ch->asyncflags &= ~ASYNC_INITIALIZED;
	restore_flags(flags);

} /* End shutdown */

/* ------------------ Begin pc_hangup  ------------------------- */

static void pc_hangup(struct tty_struct *tty)
{ /* Begin pc_hangup */

	struct channel *ch;
	
	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) != NULL) 
	{ /* Begin if ch != NULL */

		unsigned long flags;

		save_flags(flags);
		cli();
		if (tty->driver->flush_buffer)
			tty->driver->flush_buffer(tty);
		tty_ldisc_flush(tty);
		shutdown(ch);

		ch->tty   = NULL;
		ch->event = 0;
		ch->count = 0;
		restore_flags(flags);
		ch->asyncflags &= ~(ASYNC_NORMAL_ACTIVE | ASYNC_INITIALIZED);
		wake_up_interruptible(&ch->open_wait);

	} /* End if ch != NULL */

} /* End pc_hangup */

/* ------------------ Begin pc_write  ------------------------- */

static int pc_write(struct tty_struct * tty,
                    const unsigned char *buf, int bytesAvailable)
{ /* Begin pc_write */

	register unsigned int head, tail;
	register int dataLen;
	register int size;
	register int amountCopied;


	struct channel *ch;
	unsigned long flags;
	int remain;
	volatile struct board_chan *bc;


	/* ----------------------------------------------------------------
		pc_write is primarily called directly by the kernel routine
		tty_write (Though it can also be called by put_char) found in
		tty_io.c.  pc_write is passed a line discipline buffer where 
		the data to be written out is stored.  The line discipline 
		implementation itself is done at the kernel level and is not 
		brought into the driver.  
	------------------------------------------------------------------- */

	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) == NULL)
		return 0;

	/* Make a pointer to the channel data structure found on the board. */

	bc   = ch->brdchan;
	size = ch->txbufsize;

	amountCopied = 0;
	save_flags(flags);
	cli();

	globalwinon(ch);

	head = bc->tin & (size - 1);
	tail = bc->tout;

	if (tail != bc->tout)
		tail = bc->tout;
	tail &= (size - 1);

	/*	If head >= tail, head has not wrapped around. */ 
	if (head >= tail) 
	{ /* Begin head has not wrapped */

		/* ---------------------------------------------------------------
			remain (much like dataLen above) represents the total amount of
			space available on the card for data.  Here dataLen represents
			the space existing between the head pointer and the end of 
			buffer.  This is important because a memcpy cannot be told to
			automatically wrap around when it hits the buffer end.
		------------------------------------------------------------------ */ 

		dataLen = size - head;
		remain = size - (head - tail) - 1;

	} /* End head has not wrapped */
	else 
	{ /* Begin head has wrapped around */

		remain = tail - head - 1;
		dataLen = remain;

	} /* End head has wrapped around */

	/* -------------------------------------------------------------------
			Check the space on the card.  If we have more data than 
			space; reduce the amount of data to fit the space.
	---------------------------------------------------------------------- */

	bytesAvailable = min(remain, bytesAvailable);

	txwinon(ch);
	while (bytesAvailable > 0) 
	{ /* Begin while there is data to copy onto card */

		/* -----------------------------------------------------------------
			If head is not wrapped, the below will make sure the first 
			data copy fills to the end of card buffer.
		------------------------------------------------------------------- */

		dataLen = min(bytesAvailable, dataLen);
		memcpy(ch->txptr + head, buf, dataLen);
		buf += dataLen;
		head += dataLen;
		amountCopied += dataLen;
		bytesAvailable -= dataLen;

		if (head >= size) 
		{
			head = 0;
			dataLen = tail;
		}

	} /* End while there is data to copy onto card */

	ch->statusflags |= TXBUSY;
	globalwinon(ch);
	bc->tin = head;

	if ((ch->statusflags & LOWWAIT) == 0) 
	{
		ch->statusflags |= LOWWAIT;
		bc->ilow = 1;
	}
	memoff(ch);
	restore_flags(flags);

	return(amountCopied);

} /* End pc_write */

/* ------------------ Begin pc_put_char  ------------------------- */

static void pc_put_char(struct tty_struct *tty, unsigned char c)
{ /* Begin pc_put_char */

   
	pc_write(tty, &c, 1);
	return;

} /* End pc_put_char */

/* ------------------ Begin pc_write_room  ------------------------- */

static int pc_write_room(struct tty_struct *tty)
{ /* Begin pc_write_room */

	int remain;
	struct channel *ch;
	unsigned long flags;
	unsigned int head, tail;
	volatile struct board_chan *bc;

	remain = 0;

	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) != NULL) 
	{
		save_flags(flags);
		cli();
		globalwinon(ch);

		bc   = ch->brdchan;
		head = bc->tin & (ch->txbufsize - 1);
		tail = bc->tout;

		if (tail != bc->tout)
			tail = bc->tout;
		/* Wrap tail if necessary */
		tail &= (ch->txbufsize - 1);

		if ((remain = tail - head - 1) < 0 )
			remain += ch->txbufsize;

		if (remain && (ch->statusflags & LOWWAIT) == 0) 
		{
			ch->statusflags |= LOWWAIT;
			bc->ilow = 1;
		}
		memoff(ch);
		restore_flags(flags);
	}

	/* Return how much room is left on card */
	return remain;

} /* End pc_write_room */

/* ------------------ Begin pc_chars_in_buffer  ---------------------- */

static int pc_chars_in_buffer(struct tty_struct *tty)
{ /* Begin pc_chars_in_buffer */

	int chars;
	unsigned int ctail, head, tail;
	int remain;
	unsigned long flags;
	struct channel *ch;
	volatile struct board_chan *bc;


	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) == NULL)
		return(0);

	save_flags(flags);
	cli();
	globalwinon(ch);

	bc = ch->brdchan;
	tail = bc->tout;
	head = bc->tin;
	ctail = ch->mailbox->cout;

	if (tail == head && ch->mailbox->cin == ctail && bc->tbusy == 0)
		chars = 0;
	else 
	{ /* Begin if some space on the card has been used */

		head = bc->tin & (ch->txbufsize - 1);
		tail &= (ch->txbufsize - 1);

		/*  --------------------------------------------------------------
			The logic here is basically opposite of the above pc_write_room
			here we are finding the amount of bytes in the buffer filled.
			Not the amount of bytes empty.
		------------------------------------------------------------------- */

		if ((remain = tail - head - 1) < 0 )
			remain += ch->txbufsize;

		chars = (int)(ch->txbufsize - remain);

		/* -------------------------------------------------------------  
			Make it possible to wakeup anything waiting for output
			in tty_ioctl.c, etc.

			If not already set.  Setup an event to indicate when the
			transmit buffer empties 
		----------------------------------------------------------------- */

		if (!(ch->statusflags & EMPTYWAIT))
			setup_empty_event(tty,ch);

	} /* End if some space on the card has been used */

	memoff(ch);
	restore_flags(flags);

	/* Return number of characters residing on card. */
	return(chars);

} /* End pc_chars_in_buffer */

/* ------------------ Begin pc_flush_buffer  ---------------------- */

static void pc_flush_buffer(struct tty_struct *tty)
{ /* Begin pc_flush_buffer */

	unsigned int tail;
	unsigned long flags;
	struct channel *ch;
	volatile struct board_chan *bc;


	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) == NULL)
		return;

	save_flags(flags);
	cli();

	globalwinon(ch);

	bc   = ch->brdchan;
	tail = bc->tout;

	/* Have FEP move tout pointer; effectively flushing transmit buffer */

	fepcmd(ch, STOUT, (unsigned) tail, 0, 0, 0);

	memoff(ch);
	restore_flags(flags);

	wake_up_interruptible(&tty->write_wait);
	tty_wakeup(tty);

} /* End pc_flush_buffer */

/* ------------------ Begin pc_flush_chars  ---------------------- */

static void pc_flush_chars(struct tty_struct *tty)
{ /* Begin pc_flush_chars */

	struct channel * ch;

	/* ---------------------------------------------------------
		verifyChannel returns the channel from the tty struct
		if it is valid.  This serves as a sanity check.
	------------------------------------------------------------- */

	if ((ch = verifyChannel(tty)) != NULL) 
	{
		unsigned long flags;

		save_flags(flags);
		cli();

		/* ----------------------------------------------------------------
			If not already set and the transmitter is busy setup an event
			to indicate when the transmit empties.
		------------------------------------------------------------------- */

		if ((ch->statusflags & TXBUSY) && !(ch->statusflags & EMPTYWAIT))
			setup_empty_event(tty,ch);

		restore_flags(flags);
	}

} /* End pc_flush_chars */

/* ------------------ Begin block_til_ready  ---------------------- */

static int block_til_ready(struct tty_struct *tty, 
                           struct file *filp, struct channel *ch)
{ /* Begin block_til_ready */

	DECLARE_WAITQUEUE(wait,current);
	int	retval, do_clocal = 0;
	unsigned long flags;


	if (tty_hung_up_p(filp))
	{
		if (ch->asyncflags & ASYNC_HUP_NOTIFY)
			retval = -EAGAIN;
		else
			retval = -ERESTARTSYS;	
		return(retval);
	}

	/* ----------------------------------------------------------------- 
		If the device is in the middle of being closed, then block
		until it's done, and then try again.
	-------------------------------------------------------------------- */
	if (ch->asyncflags & ASYNC_CLOSING) 
	{
		interruptible_sleep_on(&ch->close_wait);

		if (ch->asyncflags & ASYNC_HUP_NOTIFY)
			return -EAGAIN;
		else
			return -ERESTARTSYS;
	}

	if (filp->f_flags & O_NONBLOCK) 
	{
		/* ----------------------------------------------------------------- 
	  	 If non-blocking mode is set, then make the check up front
	  	 and then exit.
		-------------------------------------------------------------------- */

		ch->asyncflags |= ASYNC_NORMAL_ACTIVE;

		return 0;
	}


	if (tty->termios->c_cflag & CLOCAL)
		do_clocal = 1;
	
   /* Block waiting for the carrier detect and the line to become free */
	
	retval = 0;
	add_wait_queue(&ch->open_wait, &wait);
	save_flags(flags);
	cli();


	/* We dec count so that pc_close will know when to free things */
	if (!tty_hung_up_p(filp))
		ch->count--;

	restore_flags(flags);

	ch->blocked_open++;

	while(1) 
	{ /* Begin forever while  */

		set_current_state(TASK_INTERRUPTIBLE);

		if (tty_hung_up_p(filp) ||
		    !(ch->asyncflags & ASYNC_INITIALIZED)) 
		{
			if (ch->asyncflags & ASYNC_HUP_NOTIFY)
				retval = -EAGAIN;
			else
				retval = -ERESTARTSYS;	
			break;
		}

		if (!(ch->asyncflags & ASYNC_CLOSING) && 
			  (do_clocal || (ch->imodem & ch->dcd)))
			break;

		if (signal_pending(current)) 
		{
			retval = -ERESTARTSYS;
			break;
		}

		/* ---------------------------------------------------------------
			Allow someone else to be scheduled.  We will occasionally go
			through this loop until one of the above conditions change.
			The below schedule call will allow other processes to enter and
			prevent this loop from hogging the cpu.
		------------------------------------------------------------------ */
		schedule();

	} /* End forever while  */

	current->state = TASK_RUNNING;
	remove_wait_queue(&ch->open_wait, &wait);
	cli();
	if (!tty_hung_up_p(filp))
		ch->count++;
	restore_flags(flags);

	ch->blocked_open--;

	if (retval)
		return retval;

	ch->asyncflags |= ASYNC_NORMAL_ACTIVE;

	return 0;

} /* End block_til_ready */	

/* ------------------ Begin pc_open  ---------------------- */

static int pc_open(struct tty_struct *tty, struct file * filp)
{ /* Begin pc_open */

	struct channel *ch;
	unsigned long flags;
	int line, retval, boardnum;
	volatile struct board_chan *bc;
	volatile unsigned int head;

	line = tty->index;
	if (line < 0 || line >= nbdevs) 
	{
		printk(KERN_ERR "<Error> - pc_open : line out of range in pc_open\n");
		tty->driver_data = NULL;
		return(-ENODEV);
	}


	ch = &digi_channels[line];
	boardnum = ch->boardnum;

	/* Check status of board configured in system.  */

	/* -----------------------------------------------------------------
		I check to see if the epca_setup routine detected an user error.  
		It might be better to put this in pc_init, but for the moment it
		goes here.
	---------------------------------------------------------------------- */

	if (invalid_lilo_config)
	{
		if (setup_error_code & INVALID_BOARD_TYPE)
			printk(KERN_ERR "<Error> - pc_open: Invalid board type specified in LILO command\n");

		if (setup_error_code & INVALID_NUM_PORTS)
			printk(KERN_ERR "<Error> - pc_open: Invalid number of ports specified in LILO command\n");

		if (setup_error_code & INVALID_MEM_BASE)
			printk(KERN_ERR "<Error> - pc_open: Invalid board memory address specified in LILO command\n");

		if (setup_error_code & INVALID_PORT_BASE)
			printk(KERN_ERR "<Error> - pc_open: Invalid board port address specified in LILO command\n");

		if (setup_error_code & INVALID_BOARD_STATUS)
			printk(KERN_ERR "<Error> - pc_open: Invalid board status specified in LILO command\n");

		if (setup_error_code & INVALID_ALTPIN)
			printk(KERN_ERR "<Error> - pc_open: Invalid board altpin specified in LILO command\n");

		tty->driver_data = NULL;   /* Mark this device as 'down' */
		return(-ENODEV);
	}

	if ((boardnum >= num_cards) || (boards[boardnum].status == DISABLED)) 
	{
		tty->driver_data = NULL;   /* Mark this device as 'down' */
		return(-ENODEV);
	}
	
	if (( bc = ch->brdchan) == 0) 
	{
		tty->driver_data = NULL;
		return(-ENODEV);
	}

	/* ------------------------------------------------------------------
		Every time a channel is opened, increment a counter.  This is 
		necessary because we do not wish to flush and shutdown the channel
		until the last app holding the channel open, closes it.	 	
	--------------------------------------------------------------------- */

	ch->count++;

	/* ----------------------------------------------------------------
		Set a kernel structures pointer to our local channel 
		structure.  This way we can get to it when passed only
		a tty struct.
	------------------------------------------------------------------ */

	tty->driver_data = ch;
	
	/* ----------------------------------------------------------------
		If this is the first time the channel has been opened, initialize
		the tty->termios struct otherwise let pc_close handle it.
	-------------------------------------------------------------------- */

	save_flags(flags);
	cli();

	globalwinon(ch);
	ch->statusflags = 0;

	/* Save boards current modem status */
	ch->imodem = bc->mstat;

	/* ----------------------------------------------------------------
	   Set receive head and tail ptrs to each other.  This indicates
	   no data available to read.
	----------------------------------------------------------------- */
	head = bc->rin;
	bc->rout = head;

	/* Set the channels associated tty structure */
	ch->tty = tty;

	/* -----------------------------------------------------------------
		The below routine generally sets up parity, baud, flow control 
		issues, etc.... It effect both control flags and input flags.
	-------------------------------------------------------------------- */
	epcaparam(tty,ch);

	ch->asyncflags |= ASYNC_INITIALIZED;
	memoff(ch);

	restore_flags(flags);

	retval = block_til_ready(tty, filp, ch);
	if (retval)
	{
		return retval;
	}

	/* -------------------------------------------------------------
		Set this again in case a hangup set it to zero while this 
		open() was waiting for the line...
	--------------------------------------------------------------- */
	ch->tty = tty;

	save_flags(flags);
	cli();
	globalwinon(ch);

	/* Enable Digi Data events */
	bc->idata = 1;

	memoff(ch);
	restore_flags(flags);

	return 0;

} /* End pc_open */

#ifdef MODULE
static int __init epca_module_init(void)
{ /* Begin init_module */

	unsigned long	flags;

	save_flags(flags);
	cli();

	pc_init();

	restore_flags(flags);

	return(0);
}

module_init(epca_module_init);
#endif

#ifdef ENABLE_PCI
static struct pci_driver epca_driver;
#endif

#ifdef MODULE
/* -------------------- Begin cleanup_module  ---------------------- */

static void __exit epca_module_exit(void)
{

	int               count, crd;
	struct board_info *bd;
	struct channel    *ch;
	unsigned long     flags;

	del_timer_sync(&epca_timer);

	save_flags(flags);
	cli();

	if ((tty_unregister_driver(pc_driver)) ||  
	    (tty_unregister_driver(pc_info)))
	{
		printk(KERN_WARNING "<Error> - DIGI : cleanup_module failed to un-register tty driver\n");
		restore_flags(flags);
		return;
	}
	put_tty_driver(pc_driver);
	put_tty_driver(pc_info);

	for (crd = 0; crd < num_cards; crd++) 
	{ /* Begin for each card */

		bd = &boards[crd];

		if (!bd)
		{ /* Begin sanity check */
			printk(KERN_ERR "<Error> - Digi : cleanup_module failed\n");
			return;
		} /* End sanity check */

		ch = card_ptr[crd]; 

		for (count = 0; count < bd->numports; count++, ch++) 
		{ /* Begin for each port */

			if (ch) 
			{
				if (ch->tty)
					tty_hangup(ch->tty);
				kfree(ch->tmp_buf);
			}

		} /* End for each port */
	} /* End for each card */

#ifdef ENABLE_PCI
	pci_unregister_driver (&epca_driver);
#endif

	restore_flags(flags);

}
module_exit(epca_module_exit);
#endif /* MODULE */

static struct tty_operations pc_ops = {
	.open = pc_open,
	.close = pc_close,
	.write = pc_write,
	.write_room = pc_write_room,
	.flush_buffer = pc_flush_buffer,
	.chars_in_buffer = pc_chars_in_buffer,
	.flush_chars = pc_flush_chars,
	.put_char = pc_put_char,
	.ioctl = pc_ioctl,
	.set_termios = pc_set_termios,
	.stop = pc_stop,
	.start = pc_start,
	.throttle = pc_throttle,
	.unthrottle = pc_unthrottle,
	.hangup = pc_hangup,
};

static int info_open(struct tty_struct *tty, struct file * filp)
{
	return 0;
}

static struct tty_operations info_ops = {
	.open = info_open,
	.ioctl = info_ioctl,
};

/* ------------------ Begin pc_init  ---------------------- */

int __init pc_init(void)
{ /* Begin pc_init */

	/* ----------------------------------------------------------------
		pc_init is called by the operating system during boot up prior to
		any open calls being made.  In the older versions of Linux (Prior
		to 2.0.0) an entry is made into tty_io.c.  A pointer to the last
		memory location (from kernel space) used (kmem_start) is passed
		to pc_init.  It is pc_inits responsibility to modify this value 
		for any memory that the Digi driver might need and then return
		this value to the operating system.  For example if the driver
		wishes to allocate 1K of kernel memory, pc_init would return 
		(kmem_start + 1024).  This memory (Between kmem_start and kmem_start
		+ 1024) would then be available for use exclusively by the driver.  
		In this case our driver does not allocate any of this kernel 
		memory.
	------------------------------------------------------------------*/

	ulong flags;
	int crd;
	struct board_info *bd;
	unsigned char board_id = 0;

#ifdef ENABLE_PCI
	int pci_boards_found, pci_count;

	pci_count = 0;
#endif /* ENABLE_PCI */

	pc_driver = alloc_tty_driver(MAX_ALLOC);
	if (!pc_driver)
		return -ENOMEM;

	pc_info = alloc_tty_driver(MAX_ALLOC);
	if (!pc_info) {
		put_tty_driver(pc_driver);
		return -ENOMEM;
	}

	/* -----------------------------------------------------------------------
		If epca_setup has not been ran by LILO set num_cards to defaults; copy
		board structure defined by digiConfig into drivers board structure.
		Note : If LILO has ran epca_setup then epca_setup will handle defining
		num_cards as well as copying the data into the board structure.
	-------------------------------------------------------------------------- */
	if (!liloconfig)
	{ /* Begin driver has been configured via. epcaconfig */

		nbdevs = NBDEVS;
		num_cards = NUMCARDS;
		memcpy((void *)&boards, (void *)&static_boards,
		       (sizeof(struct board_info) * NUMCARDS));
	} /* End driver has been configured via. epcaconfig */

	/* -----------------------------------------------------------------
		Note : If lilo was used to configure the driver and the 
		ignore epcaconfig option was choosen (digiepca=2) then 
		nbdevs and num_cards will equal 0 at this point.  This is
		okay; PCI cards will still be picked up if detected.
	--------------------------------------------------------------------- */

	/*  -----------------------------------------------------------
		Set up interrupt, we will worry about memory allocation in
		post_fep_init. 
	--------------------------------------------------------------- */


	printk(KERN_INFO "DIGI epca driver version %s loaded.\n",VERSION);

#ifdef ENABLE_PCI

	/* ------------------------------------------------------------------
		NOTE : This code assumes that the number of ports found in 
		       the boards array is correct.  This could be wrong if
		       the card in question is PCI (And therefore has no ports 
		       entry in the boards structure.)  The rest of the 
		       information will be valid for PCI because the beginning
		       of pc_init scans for PCI and determines i/o and base
		       memory addresses.  I am not sure if it is possible to 
		       read the number of ports supported by the card prior to
		       it being booted (Since that is the state it is in when 
		       pc_init is run).  Because it is not possible to query the
		       number of supported ports until after the card has booted;
		       we are required to calculate the card_ptrs as the card is	 
		       is initialized (Inside post_fep_init).  The negative thing
		       about this approach is that digiDload's call to GET_INFO
		       will have a bad port value.  (Since this is called prior
		       to post_fep_init.)

	--------------------------------------------------------------------- */
  
	pci_boards_found = 0;
	if(num_cards < MAXBOARDS)
		pci_boards_found += init_PCI();
	num_cards += pci_boards_found;

#endif /* ENABLE_PCI */

	pc_driver->owner = THIS_MODULE;
	pc_driver->name = "ttyD"; 
	pc_driver->devfs_name = "tts/D";
	pc_driver->major = DIGI_MAJOR; 
	pc_driver->minor_start = 0;
	pc_driver->type = TTY_DRIVER_TYPE_SERIAL;
	pc_driver->subtype = SERIAL_TYPE_NORMAL;
	pc_driver->init_termios = tty_std_termios;
	pc_driver->init_termios.c_iflag = 0;
	pc_driver->init_termios.c_oflag = 0;
	pc_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | CLOCAL | HUPCL;
	pc_driver->init_termios.c_lflag = 0;
	pc_driver->flags = TTY_DRIVER_REAL_RAW;
	tty_set_operations(pc_driver, &pc_ops);

	pc_info->owner = THIS_MODULE;
	pc_info->name = "digi_ctl";
	pc_info->major = DIGIINFOMAJOR;
	pc_info->minor_start = 0;
	pc_info->type = TTY_DRIVER_TYPE_SERIAL;
	pc_info->subtype = SERIAL_TYPE_INFO;
	pc_info->init_termios = tty_std_termios;
	pc_info->init_termios.c_iflag = 0;
	pc_info->init_termios.c_oflag = 0;
	pc_info->init_termios.c_lflag = 0;
	pc_info->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
	pc_info->flags = TTY_DRIVER_REAL_RAW;
	tty_set_operations(pc_info, &info_ops);


	save_flags(flags);
	cli();

	for (crd = 0; crd < num_cards; crd++) 
	{ /* Begin for each card */

		/*  ------------------------------------------------------------------
			This is where the appropriate memory handlers for the hardware is
			set.  Everything at runtime blindly jumps through these vectors.
		---------------------------------------------------------------------- */

		/* defined in epcaconfig.h */
		bd = &boards[crd];

		switch (bd->type)
		{ /* Begin switch on bd->type {board type} */
			case PCXEM:
			case EISAXEM:
				bd->memwinon     = pcxem_memwinon ;
				bd->memwinoff    = pcxem_memwinoff ;
				bd->globalwinon  = pcxem_globalwinon ;
				bd->txwinon      = pcxem_txwinon ;
				bd->rxwinon      = pcxem_rxwinon ;
				bd->memoff       = pcxem_memoff ;
				bd->assertgwinon = dummy_assertgwinon;
				bd->assertmemoff = dummy_assertmemoff;
				break;

			case PCIXEM:
			case PCIXRJ:
			case PCIXR:
				bd->memwinon     = dummy_memwinon;
				bd->memwinoff    = dummy_memwinoff;
				bd->globalwinon  = dummy_globalwinon;
				bd->txwinon      = dummy_txwinon;
				bd->rxwinon      = dummy_rxwinon;
				bd->memoff       = dummy_memoff;
				bd->assertgwinon = dummy_assertgwinon;
				bd->assertmemoff = dummy_assertmemoff;
				break;

			case PCXE:
			case PCXEVE:

				bd->memwinon     = pcxe_memwinon;
				bd->memwinoff    = pcxe_memwinoff;
				bd->globalwinon  = pcxe_globalwinon;
				bd->txwinon      = pcxe_txwinon;
				bd->rxwinon      = pcxe_rxwinon;
				bd->memoff       = pcxe_memoff;
				bd->assertgwinon = dummy_assertgwinon;
				bd->assertmemoff = dummy_assertmemoff;
				break;

			case PCXI:
			case PC64XE:

				bd->memwinon     = pcxi_memwinon;
				bd->memwinoff    = pcxi_memwinoff;
				bd->globalwinon  = pcxi_globalwinon;
				bd->txwinon      = pcxi_txwinon;
				bd->rxwinon      = pcxi_rxwinon;
				bd->memoff       = pcxi_memoff;
				bd->assertgwinon = pcxi_assertgwinon;
				bd->assertmemoff = pcxi_assertmemoff;
				break;

			default:
				break;

		} /* End switch on bd->type */

		/* ---------------------------------------------------------------
			Some cards need a memory segment to be defined for use in 
			transmit and receive windowing operations.  These boards
			are listed in the below switch.  In the case of the XI the
			amount of memory on the board is variable so the memory_seg
			is also variable.  This code determines what they segment 
			should be.
		----------------------------------------------------------------- */

		switch (bd->type)
		{ /* Begin switch on bd->type {board type} */

			case PCXE:
			case PCXEVE:
			case PC64XE:
				bd->memory_seg = 0xf000;
			break;

			case PCXI:
				board_id = inb((int)bd->port);
				if ((board_id & 0x1) == 0x1) 
				{ /* Begin it's an XI card */ 

					/* Is it a 64K board */
					if ((board_id & 0x30) == 0) 
						bd->memory_seg = 0xf000;

					/* Is it a 128K board */
					if ((board_id & 0x30) == 0x10) 
						bd->memory_seg = 0xe000;

					/* Is is a 256K board */	
					if ((board_id & 0x30) == 0x20) 
						bd->memory_seg = 0xc000;

					/* Is it a 512K board */
					if ((board_id & 0x30) == 0x30) 
						bd->memory_seg = 0x8000;

				} /* End it is an XI card */
				else
				{
					printk(KERN_ERR "<Error> - Board at 0x%x doesn't appear to be an XI\n",(int)bd->port);
				}
			break;

		} /* End switch on bd->type */

	} /* End for each card */

	if (tty_register_driver(pc_driver))
		panic("Couldn't register Digi PC/ driver");

	if (tty_register_driver(pc_info))
		panic("Couldn't register Digi PC/ info ");

	/* -------------------------------------------------------------------
	   Start up the poller to check for events on all enabled boards
	---------------------------------------------------------------------- */

	init_timer(&epca_timer);
	epca_timer.function = epcapoll;
	mod_timer(&epca_timer, jiffies + HZ/25);

	restore_flags(flags);

	return 0;

} /* End pc_init */

/* ------------------ Begin post_fep_init  ---------------------- */

static void post_fep_init(unsigned int crd)
{ /* Begin post_fep_init */

	int i;
	unchar *memaddr;
	volatile struct global_data *gd;
	struct board_info *bd;
	volatile struct board_chan *bc;
	struct channel *ch; 
	int shrinkmem = 0, lowwater ; 
 
	/*  -------------------------------------------------------------
		This call is made by the user via. the ioctl call DIGI_INIT.
		It is responsible for setting up all the card specific stuff.
	---------------------------------------------------------------- */
	bd = &boards[crd];

	/* -----------------------------------------------------------------
		If this is a PCI board, get the port info.  Remember PCI cards
		do not have entries into the epcaconfig.h file, so we can't get 
		the number of ports from it.  Unfortunetly, this means that anyone
		doing a DIGI_GETINFO before the board has booted will get an invalid
		number of ports returned (It should return 0).  Calls to DIGI_GETINFO
		after DIGI_INIT has been called will return the proper values. 
	------------------------------------------------------------------- */

	if (bd->type >= PCIXEM) /* If the board in question is PCI */
	{ /* Begin get PCI number of ports */

		/* --------------------------------------------------------------------
			Below we use XEMPORTS as a memory offset regardless of which PCI
			card it is.  This is because all of the supported PCI cards have
			the same memory offset for the channel data.  This will have to be
			changed if we ever develop a PCI/XE card.  NOTE : The FEP manual
			states that the port offset is 0xC22 as opposed to 0xC02.  This is
			only true for PC/XE, and PC/XI cards; not for the XEM, or CX series.
			On the PCI cards the number of ports is determined by reading a 
			ID PROM located in the box attached to the card.  The card can then
			determine the index the id to determine the number of ports available.
			(FYI - The id should be located at 0x1ac (And may use up to 4 bytes
			if the box in question is a XEM or CX)).  
		------------------------------------------------------------------------ */ 

		bd->numports = (unsigned short)*(unsigned char *)bus_to_virt((unsigned long)
                                                       (bd->re_map_membase + XEMPORTS));

		
		epcaassert(bd->numports <= 64,"PCI returned a invalid number of ports");
		nbdevs += (bd->numports);

	} /* End get PCI number of ports */

	if (crd != 0)
		card_ptr[crd] = card_ptr[crd-1] + boards[crd-1].numports;
	else
		card_ptr[crd] = &digi_channels[crd]; /* <- For card 0 only */

	ch = card_ptr[crd];


	epcaassert(ch <= &digi_channels[nbdevs - 1], "ch out of range");

	memaddr = (unchar *)bd->re_map_membase;

	/* 
	   The below command is necessary because newer kernels (2.1.x and
	   up) do not have a 1:1 virtual to physical mapping.  The below
	   call adjust…