/*****************************************************************************/

/*
 *	istallion.c  -- stallion intelligent multiport serial driver.
 *
 *	Copyright (C) 1996-1999  Stallion Technologies
 *	Copyright (C) 1994-1996  Greg Ungerer.
 *
 *	This code is loosely based on the Linux serial driver, written by
 *	Linus Torvalds, Theodore T'so and others.
 *
 *	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.
 */

/*****************************************************************************/

#include <linux/config.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/cdk.h>
#include <linux/comstats.h>
#include <linux/istallion.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/device.h>
#include <linux/wait.h>

#include <asm/io.h>
#include <asm/uaccess.h>

#ifdef CONFIG_PCI
#include <linux/pci.h>
#endif

/*****************************************************************************/

/*
 *	Define different board types. Not all of the following board types
 *	are supported by this driver. But I will use the standard "assigned"
 *	board numbers. Currently supported boards are abbreviated as:
 *	ECP = EasyConnection 8/64, ONB = ONboard, BBY = Brumby and
 *	STAL = Stallion.
 */
#define	BRD_UNKNOWN	0
#define	BRD_STALLION	1
#define	BRD_BRUMBY4	2
#define	BRD_ONBOARD2	3
#define	BRD_ONBOARD	4
#define	BRD_BRUMBY8	5
#define	BRD_BRUMBY16	6
#define	BRD_ONBOARDE	7
#define	BRD_ONBOARD32	9
#define	BRD_ONBOARD2_32	10
#define	BRD_ONBOARDRS	11
#define	BRD_EASYIO	20
#define	BRD_ECH		21
#define	BRD_ECHMC	22
#define	BRD_ECP		23
#define BRD_ECPE	24
#define	BRD_ECPMC	25
#define	BRD_ECHPCI	26
#define	BRD_ECH64PCI	27
#define	BRD_EASYIOPCI	28
#define	BRD_ECPPCI	29

#define	BRD_BRUMBY	BRD_BRUMBY4

/*
 *	Define a configuration structure to hold the board configuration.
 *	Need to set this up in the code (for now) with the boards that are
 *	to be configured into the system. This is what needs to be modified
 *	when adding/removing/modifying boards. Each line entry in the
 *	stli_brdconf[] array is a board. Each line contains io/irq/memory
 *	ranges for that board (as well as what type of board it is).
 *	Some examples:
 *		{ BRD_ECP, 0x2a0, 0, 0xcc000, 0, 0 },
 *	This line will configure an EasyConnection 8/64 at io address 2a0,
 *	and shared memory address of cc000. Multiple EasyConnection 8/64
 *	boards can share the same shared memory address space. No interrupt
 *	is required for this board type.
 *	Another example:
 *		{ BRD_ECPE, 0x5000, 0, 0x80000000, 0, 0 },
 *	This line will configure an EasyConnection 8/64 EISA in slot 5 and
 *	shared memory address of 0x80000000 (2 GByte). Multiple
 *	EasyConnection 8/64 EISA boards can share the same shared memory
 *	address space. No interrupt is required for this board type.
 *	Another example:
 *		{ BRD_ONBOARD, 0x240, 0, 0xd0000, 0, 0 },
 *	This line will configure an ONboard (ISA type) at io address 240,
 *	and shared memory address of d0000. Multiple ONboards can share
 *	the same shared memory address space. No interrupt required.
 *	Another example:
 *		{ BRD_BRUMBY4, 0x360, 0, 0xc8000, 0, 0 },
 *	This line will configure a Brumby board (any number of ports!) at
 *	io address 360 and shared memory address of c8000. All Brumby boards
 *	configured into a system must have their own separate io and memory
 *	addresses. No interrupt is required.
 *	Another example:
 *		{ BRD_STALLION, 0x330, 0, 0xd0000, 0, 0 },
 *	This line will configure an original Stallion board at io address 330
 *	and shared memory address d0000 (this would only be valid for a "V4.0"
 *	or Rev.O Stallion board). All Stallion boards configured into the
 *	system must have their own separate io and memory addresses. No
 *	interrupt is required.
 */

typedef struct {
	int		brdtype;
	int		ioaddr1;
	int		ioaddr2;
	unsigned long	memaddr;
	int		irq;
	int		irqtype;
} stlconf_t;

static stlconf_t	stli_brdconf[] = {
	/*{ BRD_ECP, 0x2a0, 0, 0xcc000, 0, 0 },*/
};

static int	stli_nrbrds = sizeof(stli_brdconf) / sizeof(stlconf_t);

/*
 *	There is some experimental EISA board detection code in this driver.
 *	By default it is disabled, but for those that want to try it out,
 *	then set the define below to be 1.
 */
#define	STLI_EISAPROBE	0

/*****************************************************************************/

/*
 *	Define some important driver characteristics. Device major numbers
 *	allocated as per Linux Device Registry.
 */
#ifndef	STL_SIOMEMMAJOR
#define	STL_SIOMEMMAJOR		28
#endif
#ifndef	STL_SERIALMAJOR
#define	STL_SERIALMAJOR		24
#endif
#ifndef	STL_CALLOUTMAJOR
#define	STL_CALLOUTMAJOR	25
#endif

/*****************************************************************************/

/*
 *	Define our local driver identity first. Set up stuff to deal with
 *	all the local structures required by a serial tty driver.
 */
static char	*stli_drvtitle = "Stallion Intelligent Multiport Serial Driver";
static char	*stli_drvname = "istallion";
static char	*stli_drvversion = "5.6.0";
static char	*stli_serialname = "ttyE";

static struct tty_driver	*stli_serial;

/*
 *	We will need to allocate a temporary write buffer for chars that
 *	come direct from user space. The problem is that a copy from user
 *	space might cause a page fault (typically on a system that is
 *	swapping!). All ports will share one buffer - since if the system
 *	is already swapping a shared buffer won't make things any worse.
 */
static char			*stli_tmpwritebuf;
static DECLARE_MUTEX(stli_tmpwritesem);

#define	STLI_TXBUFSIZE		4096

/*
 *	Use a fast local buffer for cooked characters. Typically a whole
 *	bunch of cooked characters come in for a port, 1 at a time. So we
 *	save those up into a local buffer, then write out the whole lot
 *	with a large memcpy. Just use 1 buffer for all ports, since its
 *	use it is only need for short periods of time by each port.
 */
static char			*stli_txcookbuf;
static int			stli_txcooksize;
static int			stli_txcookrealsize;
static struct tty_struct	*stli_txcooktty;

/*
 *	Define a local default termios struct. All ports will be created
 *	with this termios initially. Basically all it defines is a raw port
 *	at 9600 baud, 8 data bits, no parity, 1 stop bit.
 */
static struct termios		stli_deftermios = {
	.c_cflag	= (B9600 | CS8 | CREAD | HUPCL | CLOCAL),
	.c_cc		= INIT_C_CC,
};

/*
 *	Define global stats structures. Not used often, and can be
 *	re-used for each stats call.
 */
static comstats_t	stli_comstats;
static combrd_t		stli_brdstats;
static asystats_t	stli_cdkstats;
static stlibrd_t	stli_dummybrd;
static stliport_t	stli_dummyport;

/*****************************************************************************/

static stlibrd_t	*stli_brds[STL_MAXBRDS];

static int		stli_shared;

/*
 *	Per board state flags. Used with the state field of the board struct.
 *	Not really much here... All we need to do is keep track of whether
 *	the board has been detected, and whether it is actually running a slave
 *	or not.
 */
#define	BST_FOUND	0x1
#define	BST_STARTED	0x2

/*
 *	Define the set of port state flags. These are marked for internal
 *	state purposes only, usually to do with the state of communications
 *	with the slave. Most of them need to be updated atomically, so always
 *	use the bit setting operations (unless protected by cli/sti).
 */
#define	ST_INITIALIZING	1
#define	ST_OPENING	2
#define	ST_CLOSING	3
#define	ST_CMDING	4
#define	ST_TXBUSY	5
#define	ST_RXING	6
#define	ST_DOFLUSHRX	7
#define	ST_DOFLUSHTX	8
#define	ST_DOSIGS	9
#define	ST_RXSTOP	10
#define	ST_GETSIGS	11

/*
 *	Define an array of board names as printable strings. Handy for
 *	referencing boards when printing trace and stuff.
 */
static char	*stli_brdnames[] = {
	"Unknown",
	"Stallion",
	"Brumby",
	"ONboard-MC",
	"ONboard",
	"Brumby",
	"Brumby",
	"ONboard-EI",
	(char *) NULL,
	"ONboard",
	"ONboard-MC",
	"ONboard-MC",
	(char *) NULL,
	(char *) NULL,
	(char *) NULL,
	(char *) NULL,
	(char *) NULL,
	(char *) NULL,
	(char *) NULL,
	(char *) NULL,
	"EasyIO",
	"EC8/32-AT",
	"EC8/32-MC",
	"EC8/64-AT",
	"EC8/64-EI",
	"EC8/64-MC",
	"EC8/32-PCI",
	"EC8/64-PCI",
	"EasyIO-PCI",
	"EC/RA-PCI",
};

/*****************************************************************************/

#ifdef MODULE
/*
 *	Define some string labels for arguments passed from the module
 *	load line. These allow for easy board definitions, and easy
 *	modification of the io, memory and irq resoucres.
 */

static char	*board0[8];
static char	*board1[8];
static char	*board2[8];
static char	*board3[8];

static char	**stli_brdsp[] = {
	(char **) &board0,
	(char **) &board1,
	(char **) &board2,
	(char **) &board3
};

/*
 *	Define a set of common board names, and types. This is used to
 *	parse any module arguments.
 */

typedef struct stlibrdtype {
	char	*name;
	int	type;
} stlibrdtype_t;

static stlibrdtype_t	stli_brdstr[] = {
	{ "stallion", BRD_STALLION },
	{ "1", BRD_STALLION },
	{ "brumby", BRD_BRUMBY },
	{ "brumby4", BRD_BRUMBY },
	{ "brumby/4", BRD_BRUMBY },
	{ "brumby-4", BRD_BRUMBY },
	{ "brumby8", BRD_BRUMBY },
	{ "brumby/8", BRD_BRUMBY },
	{ "brumby-8", BRD_BRUMBY },
	{ "brumby16", BRD_BRUMBY },
	{ "brumby/16", BRD_BRUMBY },
	{ "brumby-16", BRD_BRUMBY },
	{ "2", BRD_BRUMBY },
	{ "onboard2", BRD_ONBOARD2 },
	{ "onboard-2", BRD_ONBOARD2 },
	{ "onboard/2", BRD_ONBOARD2 },
	{ "onboard-mc", BRD_ONBOARD2 },
	{ "onboard/mc", BRD_ONBOARD2 },
	{ "onboard-mca", BRD_ONBOARD2 },
	{ "onboard/mca", BRD_ONBOARD2 },
	{ "3", BRD_ONBOARD2 },
	{ "onboard", BRD_ONBOARD },
	{ "onboardat", BRD_ONBOARD },
	{ "4", BRD_ONBOARD },
	{ "onboarde", BRD_ONBOARDE },
	{ "onboard-e", BRD_ONBOARDE },
	{ "onboard/e", BRD_ONBOARDE },
	{ "onboard-ei", BRD_ONBOARDE },
	{ "onboard/ei", BRD_ONBOARDE },
	{ "7", BRD_ONBOARDE },
	{ "ecp", BRD_ECP },
	{ "ecpat", BRD_ECP },
	{ "ec8/64", BRD_ECP },
	{ "ec8/64-at", BRD_ECP },
	{ "ec8/64-isa", BRD_ECP },
	{ "23", BRD_ECP },
	{ "ecpe", BRD_ECPE },
	{ "ecpei", BRD_ECPE },
	{ "ec8/64-e", BRD_ECPE },
	{ "ec8/64-ei", BRD_ECPE },
	{ "24", BRD_ECPE },
	{ "ecpmc", BRD_ECPMC },
	{ "ec8/64-mc", BRD_ECPMC },
	{ "ec8/64-mca", BRD_ECPMC },
	{ "25", BRD_ECPMC },
	{ "ecppci", BRD_ECPPCI },
	{ "ec/ra", BRD_ECPPCI },
	{ "ec/ra-pc", BRD_ECPPCI },
	{ "ec/ra-pci", BRD_ECPPCI },
	{ "29", BRD_ECPPCI },
};

/*
 *	Define the module agruments.
 */
MODULE_AUTHOR("Greg Ungerer");
MODULE_DESCRIPTION("Stallion Intelligent Multiport Serial Driver");
MODULE_LICENSE("GPL");


MODULE_PARM(board0, "1-3s");
MODULE_PARM_DESC(board0, "Board 0 config -> name[,ioaddr[,memaddr]");
MODULE_PARM(board1, "1-3s");
MODULE_PARM_DESC(board1, "Board 1 config -> name[,ioaddr[,memaddr]");
MODULE_PARM(board2, "1-3s");
MODULE_PARM_DESC(board2, "Board 2 config -> name[,ioaddr[,memaddr]");
MODULE_PARM(board3, "1-3s");
MODULE_PARM_DESC(board3, "Board 3 config -> name[,ioaddr[,memaddr]");

#endif

/*
 *	Set up a default memory address table for EISA board probing.
 *	The default addresses are all bellow 1Mbyte, which has to be the
 *	case anyway. They should be safe, since we only read values from
 *	them, and interrupts are disabled while we do it. If the higher
 *	memory support is compiled in then we also try probing around
 *	the 1Gb, 2Gb and 3Gb areas as well...
 */
static unsigned long	stli_eisamemprobeaddrs[] = {
	0xc0000,    0xd0000,    0xe0000,    0xf0000,
	0x80000000, 0x80010000, 0x80020000, 0x80030000,
	0x40000000, 0x40010000, 0x40020000, 0x40030000,
	0xc0000000, 0xc0010000, 0xc0020000, 0xc0030000,
	0xff000000, 0xff010000, 0xff020000, 0xff030000,
};

static int	stli_eisamempsize = sizeof(stli_eisamemprobeaddrs) / sizeof(unsigned long);
int		stli_eisaprobe = STLI_EISAPROBE;

/*
 *	Define the Stallion PCI vendor and device IDs.
 */
#ifdef CONFIG_PCI
#ifndef	PCI_VENDOR_ID_STALLION
#define	PCI_VENDOR_ID_STALLION		0x124d
#endif
#ifndef PCI_DEVICE_ID_ECRA
#define	PCI_DEVICE_ID_ECRA		0x0004
#endif

static struct pci_device_id istallion_pci_tbl[] = {
	{ PCI_VENDOR_ID_STALLION, PCI_DEVICE_ID_ECRA, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0 },
	{ 0 }
};
MODULE_DEVICE_TABLE(pci, istallion_pci_tbl);

#endif /* CONFIG_PCI */

/*****************************************************************************/

/*
 *	Hardware configuration info for ECP boards. These defines apply
 *	to the directly accessible io ports of the ECP. There is a set of
 *	defines for each ECP board type, ISA, EISA, MCA and PCI.
 */
#define	ECP_IOSIZE	4

#define	ECP_MEMSIZE	(128 * 1024)
#define	ECP_PCIMEMSIZE	(256 * 1024)

#define	ECP_ATPAGESIZE	(4 * 1024)
#define	ECP_MCPAGESIZE	(4 * 1024)
#define	ECP_EIPAGESIZE	(64 * 1024)
#define	ECP_PCIPAGESIZE	(64 * 1024)

#define	STL_EISAID	0x8c4e

/*
 *	Important defines for the ISA class of ECP board.
 */
#define	ECP_ATIREG	0
#define	ECP_ATCONFR	1
#define	ECP_ATMEMAR	2
#define	ECP_ATMEMPR	3
#define	ECP_ATSTOP	0x1
#define	ECP_ATINTENAB	0x10
#define	ECP_ATENABLE	0x20
#define	ECP_ATDISABLE	0x00
#define	ECP_ATADDRMASK	0x3f000
#define	ECP_ATADDRSHFT	12

/*
 *	Important defines for the EISA class of ECP board.
 */
#define	ECP_EIIREG	0
#define	ECP_EIMEMARL	1
#define	ECP_EICONFR	2
#define	ECP_EIMEMARH	3
#define	ECP_EIENABLE	0x1
#define	ECP_EIDISABLE	0x0
#define	ECP_EISTOP	0x4
#define	ECP_EIEDGE	0x00
#define	ECP_EILEVEL	0x80
#define	ECP_EIADDRMASKL	0x00ff0000
#define	ECP_EIADDRSHFTL	16
#define	ECP_EIADDRMASKH	0xff000000
#define	ECP_EIADDRSHFTH	24
#define	ECP_EIBRDENAB	0xc84

#define	ECP_EISAID	0x4

/*
 *	Important defines for the Micro-channel class of ECP board.
 *	(It has a lot in common with the ISA boards.)
 */
#define	ECP_MCIREG	0
#define	ECP_MCCONFR	1
#define	ECP_MCSTOP	0x20
#define	ECP_MCENABLE	0x80
#define	ECP_MCDISABLE	0x00

/*
 *	Important defines for the PCI class of ECP board.
 *	(It has a lot in common with the other ECP boards.)
 */
#define	ECP_PCIIREG	0
#define	ECP_PCICONFR	1
#define	ECP_PCISTOP	0x01

/*
 *	Hardware configuration info for ONboard and Brumby boards. These
 *	defines apply to the directly accessible io ports of these boards.
 */
#define	ONB_IOSIZE	16
#define	ONB_MEMSIZE	(64 * 1024)
#define	ONB_ATPAGESIZE	(64 * 1024)
#define	ONB_MCPAGESIZE	(64 * 1024)
#define	ONB_EIMEMSIZE	(128 * 1024)
#define	ONB_EIPAGESIZE	(64 * 1024)

/*
 *	Important defines for the ISA class of ONboard board.
 */
#define	ONB_ATIREG	0
#define	ONB_ATMEMAR	1
#define	ONB_ATCONFR	2
#define	ONB_ATSTOP	0x4
#define	ONB_ATENABLE	0x01
#define	ONB_ATDISABLE	0x00
#define	ONB_ATADDRMASK	0xff0000
#define	ONB_ATADDRSHFT	16

#define	ONB_MEMENABLO	0
#define	ONB_MEMENABHI	0x02

/*
 *	Important defines for the EISA class of ONboard board.
 */
#define	ONB_EIIREG	0
#define	ONB_EIMEMARL	1
#define	ONB_EICONFR	2
#define	ONB_EIMEMARH	3
#define	ONB_EIENABLE	0x1
#define	ONB_EIDISABLE	0x0
#define	ONB_EISTOP	0x4
#define	ONB_EIEDGE	0x00
#define	ONB_EILEVEL	0x80
#define	ONB_EIADDRMASKL	0x00ff0000
#define	ONB_EIADDRSHFTL	16
#define	ONB_EIADDRMASKH	0xff000000
#define	ONB_EIADDRSHFTH	24
#define	ONB_EIBRDENAB	0xc84

#define	ONB_EISAID	0x1

/*
 *	Important defines for the Brumby boards. They are pretty simple,
 *	there is not much that is programmably configurable.
 */
#define	BBY_IOSIZE	16
#define	BBY_MEMSIZE	(64 * 1024)
#define	BBY_PAGESIZE	(16 * 1024)

#define	BBY_ATIREG	0
#define	BBY_ATCONFR	1
#define	BBY_ATSTOP	0x4

/*
 *	Important defines for the Stallion boards. They are pretty simple,
 *	there is not much that is programmably configurable.
 */
#define	STAL_IOSIZE	16
#define	STAL_MEMSIZE	(64 * 1024)
#define	STAL_PAGESIZE	(64 * 1024)

/*
 *	Define the set of status register values for EasyConnection panels.
 *	The signature will return with the status value for each panel. From
 *	this we can determine what is attached to the board - before we have
 *	actually down loaded any code to it.
 */
#define	ECH_PNLSTATUS	2
#define	ECH_PNL16PORT	0x20
#define	ECH_PNLIDMASK	0x07
#define	ECH_PNLXPID	0x40
#define	ECH_PNLINTRPEND	0x80

/*
 *	Define some macros to do things to the board. Even those these boards
 *	are somewhat related there is often significantly different ways of
 *	doing some operation on it (like enable, paging, reset, etc). So each
 *	board class has a set of functions which do the commonly required
 *	operations. The macros below basically just call these functions,
 *	generally checking for a NULL function - which means that the board
 *	needs nothing done to it to achieve this operation!
 */
#define	EBRDINIT(brdp)						\
	if (brdp->init != NULL)					\
		(* brdp->init)(brdp)

#define	EBRDENABLE(brdp)					\
	if (brdp->enable != NULL)				\
		(* brdp->enable)(brdp);

#define	EBRDDISABLE(brdp)					\
	if (brdp->disable != NULL)				\
		(* brdp->disable)(brdp);

#define	EBRDINTR(brdp)						\
	if (brdp->intr != NULL)					\
		(* brdp->intr)(brdp);

#define	EBRDRESET(brdp)						\
	if (brdp->reset != NULL)				\
		(* brdp->reset)(brdp);

#define	EBRDGETMEMPTR(brdp,offset)				\
	(* brdp->getmemptr)(brdp, offset, __LINE__)

/*
 *	Define the maximal baud rate, and the default baud base for ports.
 */
#define	STL_MAXBAUD	460800
#define	STL_BAUDBASE	115200
#define	STL_CLOSEDELAY	(5 * HZ / 10)

/*****************************************************************************/

/*
 *	Define macros to extract a brd or port number from a minor number.
 */
#define	MINOR2BRD(min)		(((min) & 0xc0) >> 6)
#define	MINOR2PORT(min)		((min) & 0x3f)

/*
 *	Define a baud rate table that converts termios baud rate selector
 *	into the actual baud rate value. All baud rate calculations are based
 *	on the actual baud rate required.
 */
static unsigned int	stli_baudrates[] = {
	0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
	9600, 19200, 38400, 57600, 115200, 230400, 460800, 921600
};

/*****************************************************************************/

/*
 *	Define some handy local macros...
 */
#undef MIN
#define	MIN(a,b)	(((a) <= (b)) ? (a) : (b))

#undef	TOLOWER
#define	TOLOWER(x)	((((x) >= 'A') && ((x) <= 'Z')) ? ((x) + 0x20) : (x))

/*****************************************************************************/

/*
 *	Prototype all functions in this driver!
 */

#ifdef MODULE
static void	stli_argbrds(void);
static int	stli_parsebrd(stlconf_t *confp, char **argp);

static unsigned long	stli_atol(char *str);
#endif

int		stli_init(void);
static int	stli_open(struct tty_struct *tty, struct file *filp);
static void	stli_close(struct tty_struct *tty, struct file *filp);
static int	stli_write(struct tty_struct *tty, const unsigned char *buf, int count);
static void	stli_putchar(struct tty_struct *tty, unsigned char ch);
static void	stli_flushchars(struct tty_struct *tty);
static int	stli_writeroom(struct tty_struct *tty);
static int	stli_charsinbuffer(struct tty_struct *tty);
static int	stli_ioctl(struct tty_struct *tty, struct file *file, unsigned int cmd, unsigned long arg);
static void	stli_settermios(struct tty_struct *tty, struct termios *old);
static void	stli_throttle(struct tty_struct *tty);
static void	stli_unthrottle(struct tty_struct *tty);
static void	stli_stop(struct tty_struct *tty);
static void	stli_start(struct tty_struct *tty);
static void	stli_flushbuffer(struct tty_struct *tty);
static void	stli_breakctl(struct tty_struct *tty, int state);
static void	stli_waituntilsent(struct tty_struct *tty, int timeout);
static void	stli_sendxchar(struct tty_struct *tty, char ch);
static void	stli_hangup(struct tty_struct *tty);
static int	stli_portinfo(stlibrd_t *brdp, stliport_t *portp, int portnr, char *pos);

static int	stli_brdinit(stlibrd_t *brdp);
static int	stli_startbrd(stlibrd_t *brdp);
static ssize_t	stli_memread(struct file *fp, char __user *buf, size_t count, loff_t *offp);
static ssize_t	stli_memwrite(struct file *fp, const char __user *buf, size_t count, loff_t *offp);
static int	stli_memioctl(struct inode *ip, struct file *fp, unsigned int cmd, unsigned long arg);
static void	stli_brdpoll(stlibrd_t *brdp, volatile cdkhdr_t *hdrp);
static void	stli_poll(unsigned long arg);
static int	stli_hostcmd(stlibrd_t *brdp, stliport_t *portp);
static int	stli_initopen(stlibrd_t *brdp, stliport_t *portp);
static int	stli_rawopen(stlibrd_t *brdp, stliport_t *portp, unsigned long arg, int wait);
static int	stli_rawclose(stlibrd_t *brdp, stliport_t *portp, unsigned long arg, int wait);
static int	stli_waitcarrier(stlibrd_t *brdp, stliport_t *portp, struct file *filp);
static void	stli_dohangup(void *arg);
static int	stli_setport(stliport_t *portp);
static int	stli_cmdwait(stlibrd_t *brdp, stliport_t *portp, unsigned long cmd, void *arg, int size, int copyback);
static void	stli_sendcmd(stlibrd_t *brdp, stliport_t *portp, unsigned long cmd, void *arg, int size, int copyback);
static void	stli_dodelaycmd(stliport_t *portp, volatile cdkctrl_t *cp);
static void	stli_mkasyport(stliport_t *portp, asyport_t *pp, struct termios *tiosp);
static void	stli_mkasysigs(asysigs_t *sp, int dtr, int rts);
static long	stli_mktiocm(unsigned long sigvalue);
static void	stli_read(stlibrd_t *brdp, stliport_t *portp);
static int	stli_getserial(stliport_t *portp, struct serial_struct __user *sp);
static int	stli_setserial(stliport_t *portp, struct serial_struct __user *sp);
static int	stli_getbrdstats(combrd_t __user *bp);
static int	stli_getportstats(stliport_t *portp, comstats_t __user *cp);
static int	stli_portcmdstats(stliport_t *portp);
static int	stli_clrportstats(stliport_t *portp, comstats_t __user *cp);
static int	stli_getportstruct(stliport_t __user *arg);
static int	stli_getbrdstruct(stlibrd_t __user *arg);
static void	*stli_memalloc(int len);
static stlibrd_t *stli_allocbrd(void);

static void	stli_ecpinit(stlibrd_t *brdp);
static void	stli_ecpenable(stlibrd_t *brdp);
static void	stli_ecpdisable(stlibrd_t *brdp);
static char	*stli_ecpgetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_ecpreset(stlibrd_t *brdp);
static void	stli_ecpintr(stlibrd_t *brdp);
static void	stli_ecpeiinit(stlibrd_t *brdp);
static void	stli_ecpeienable(stlibrd_t *brdp);
static void	stli_ecpeidisable(stlibrd_t *brdp);
static char	*stli_ecpeigetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_ecpeireset(stlibrd_t *brdp);
static void	stli_ecpmcenable(stlibrd_t *brdp);
static void	stli_ecpmcdisable(stlibrd_t *brdp);
static char	*stli_ecpmcgetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_ecpmcreset(stlibrd_t *brdp);
static void	stli_ecppciinit(stlibrd_t *brdp);
static char	*stli_ecppcigetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_ecppcireset(stlibrd_t *brdp);

static void	stli_onbinit(stlibrd_t *brdp);
static void	stli_onbenable(stlibrd_t *brdp);
static void	stli_onbdisable(stlibrd_t *brdp);
static char	*stli_onbgetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_onbreset(stlibrd_t *brdp);
static void	stli_onbeinit(stlibrd_t *brdp);
static void	stli_onbeenable(stlibrd_t *brdp);
static void	stli_onbedisable(stlibrd_t *brdp);
static char	*stli_onbegetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_onbereset(stlibrd_t *brdp);
static void	stli_bbyinit(stlibrd_t *brdp);
static char	*stli_bbygetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_bbyreset(stlibrd_t *brdp);
static void	stli_stalinit(stlibrd_t *brdp);
static char	*stli_stalgetmemptr(stlibrd_t *brdp, unsigned long offset, int line);
static void	stli_stalreset(stlibrd_t *brdp);

static stliport_t *stli_getport(int brdnr, int panelnr, int portnr);

static int	stli_initecp(stlibrd_t *brdp);
static int	stli_initonb(stlibrd_t *brdp);
static int	stli_eisamemprobe(stlibrd_t *brdp);
static int	stli_initports(stlibrd_t *brdp);

#ifdef	CONFIG_PCI
static int	stli_initpcibrd(int brdtype, struct pci_dev *devp);
#endif

/*****************************************************************************/

/*
 *	Define the driver info for a user level shared memory device. This
 *	device will work sort of like the /dev/kmem device - except that it
 *	will give access to the shared memory on the Stallion intelligent
 *	board. This is also a very useful debugging tool.
 */
static struct file_operations	stli_fsiomem = {
	.owner		= THIS_MODULE,
	.read		= stli_memread,
	.write		= stli_memwrite,
	.ioctl		= stli_memioctl,
};

/*****************************************************************************/

/*
 *	Define a timer_list entry for our poll routine. The slave board
 *	is polled every so often to see if anything needs doing. This is
 *	much cheaper on host cpu than using interrupts. It turns out to
 *	not increase character latency by much either...
 */
static struct timer_list stli_timerlist = TIMER_INITIALIZER(stli_poll, 0, 0);

static int	stli_timeron;

/*
 *	Define the calculation for the timeout routine.
 */
#define	STLI_TIMEOUT	(jiffies + 1)

/*****************************************************************************/

static struct class_simple *istallion_class;

#ifdef MODULE

/*
 *	Loadable module initialization stuff.
 */

static int __init istallion_module_init(void)
{
	unsigned long	flags;

#ifdef DEBUG
	printk("init_module()\n");
#endif

	save_flags(flags);
	cli();
	stli_init();
	restore_flags(flags);

	return(0);
}

/*****************************************************************************/

static void __exit istallion_module_exit(void)
{
	stlibrd_t	*brdp;
	stliport_t	*portp;
	unsigned long	flags;
	int		i, j;

#ifdef DEBUG
	printk("cleanup_module()\n");
#endif

	printk(KERN_INFO "Unloading %s: version %s\n", stli_drvtitle,
		stli_drvversion);

	save_flags(flags);
	cli();

/*
 *	Free up all allocated resources used by the ports. This includes
 *	memory and interrupts.
 */
	if (stli_timeron) {
		stli_timeron = 0;
		del_timer(&stli_timerlist);
	}

	i = tty_unregister_driver(stli_serial);
	if (i) {
		printk("STALLION: failed to un-register tty driver, "
			"errno=%d\n", -i);
		restore_flags(flags);
		return;
	}
	put_tty_driver(stli_serial);
	for (i = 0; i < 4; i++) {
		devfs_remove("staliomem/%d", i);
		class_simple_device_remove(MKDEV(STL_SIOMEMMAJOR, i));
	}
	devfs_remove("staliomem");
	class_simple_destroy(istallion_class);
	if ((i = unregister_chrdev(STL_SIOMEMMAJOR, "staliomem")))
		printk("STALLION: failed to un-register serial memory device, "
			"errno=%d\n", -i);
	if (stli_tmpwritebuf != (char *) NULL)
		kfree(stli_tmpwritebuf);
	if (stli_txcookbuf != (char *) NULL)
		kfree(stli_txcookbuf);

	for (i = 0; (i < stli_nrbrds); i++) {
		if ((brdp = stli_brds[i]) == (stlibrd_t *) NULL)
			continue;
		for (j = 0; (j < STL_MAXPORTS); j++) {
			portp = brdp->ports[j];
			if (portp != (stliport_t *) NULL) {
				if (portp->tty != (struct tty_struct *) NULL)
					tty_hangup(portp->tty);
				kfree(portp);
			}
		}

		iounmap(brdp->membase);
		if (brdp->iosize > 0)
			release_region(brdp->iobase, brdp->iosize);
		kfree(brdp);
		stli_brds[i] = (stlibrd_t *) NULL;
	}

	restore_flags(flags);
}

module_init(istallion_module_init);
module_exit(istallion_module_exit);

/*****************************************************************************/

/*
 *	Check for any arguments passed in on the module load command line.
 */

static void stli_argbrds(void)
{
	stlconf_t	conf;
	stlibrd_t	*brdp;
	int		nrargs, i;

#ifdef DEBUG
	printk("stli_argbrds()\n");
#endif

	nrargs = sizeof(stli_brdsp) / sizeof(char **);

	for (i = stli_nrbrds; (i < nrargs); i++) {
		memset(&conf, 0, sizeof(conf));
		if (stli_parsebrd(&conf, stli_brdsp[i]) == 0)
			continue;
		if ((brdp = stli_allocbrd()) == (stlibrd_t *) NULL)
			continue;
		stli_nrbrds = i + 1;
		brdp->brdnr = i;
		brdp->brdtype = conf.brdtype;
		brdp->iobase = conf.ioaddr1;
		brdp->memaddr = conf.memaddr;
		stli_brdinit(brdp);
	}
}

/*****************************************************************************/

/*
 *	Convert an ascii string number into an unsigned long.
 */

static unsigned long stli_atol(char *str)
{
	unsigned long	val;
	int		base, c;
	char		*sp;

	val = 0;
	sp = str;
	if ((*sp == '0') && (*(sp+1) == 'x')) {
		base = 16;
		sp += 2;
	} else if (*sp == '0') {
		base = 8;
		sp++;
	} else {
		base = 10;
	}

	for (; (*sp != 0); sp++) {
		c = (*sp > '9') ? (TOLOWER(*sp) - 'a' + 10) : (*sp - '0');
		if ((c < 0) || (c >= base)) {
			printk("STALLION: invalid argument %s\n", str);
			val = 0;
			break;
		}
		val = (val * base) + c;
	}
	return(val);
}

/*****************************************************************************/

/*
 *	Parse the supplied argument string, into the board conf struct.
 */

static int stli_parsebrd(stlconf_t *confp, char **argp)
{
	char	*sp;
	int	nrbrdnames, i;

#ifdef DEBUG
	printk("stli_parsebrd(confp=%x,argp=%x)\n", (int) confp, (int) argp);
#endif

	if ((argp[0] == (char *) NULL) || (*argp[0] == 0))
		return(0);

	for (sp = argp[0], i = 0; ((*sp != 0) && (i < 25)); sp++, i++)
		*sp = TOLOWER(*sp);

	nrbrdnames = sizeof(stli_brdstr) / sizeof(stlibrdtype_t);
	for (i = 0; (i < nrbrdnames); i++) {
		if (strcmp(stli_brdstr[i].name, argp[0]) == 0)
			break;
	}
	if (i >= nrbrdnames) {
		printk("STALLION: unknown board name, %s?\n", argp[0]);
		return(0);
	}

	confp->brdtype = stli_brdstr[i].type;
	if ((argp[1] != (char *) NULL) && (*argp[1] != 0))
		confp->ioaddr1 = stli_atol(argp[1]);
	if ((argp[2] != (char *) NULL) && (*argp[2] != 0))
		confp->memaddr = stli_atol(argp[2]);
	return(1);
}

#endif

/*****************************************************************************/

/*
 *	Local driver kernel malloc routine.
 */

static void *stli_memalloc(int len)
{
	return((void *) kmalloc(len, GFP_KERNEL));
}

/*****************************************************************************/

static int stli_open(struct tty_struct *tty, struct file *filp)
{
	stlibrd_t	*brdp;
	stliport_t	*portp;
	unsigned int	minordev;
	int		brdnr, portnr, rc;

#ifdef DEBUG
	printk("stli_open(tty=%x,filp=%x): device=%s\n", (int) tty,
		(int) filp, tty->name);
#endif

	minordev = tty->index;
	brdnr = MINOR2BRD(minordev);
	if (brdnr >= stli_nrbrds)
		return(-ENODEV);
	brdp = stli_brds[brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return(-ENODEV);
	if ((brdp->state & BST_STARTED) == 0)
		return(-ENODEV);
	portnr = MINOR2PORT(minordev);
	if ((portnr < 0) || (portnr > brdp->nrports))
		return(-ENODEV);

	portp = brdp->ports[portnr];
	if (portp == (stliport_t *) NULL)
		return(-ENODEV);
	if (portp->devnr < 1)
		return(-ENODEV);


/*
 *	Check if this port is in the middle of closing. If so then wait
 *	until it is closed then return error status based on flag settings.
 *	The sleep here does not need interrupt protection since the wakeup
 *	for it is done with the same context.
 */
	if (portp->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&portp->close_wait);
		if (portp->flags & ASYNC_HUP_NOTIFY)
			return(-EAGAIN);
		return(-ERESTARTSYS);
	}

/*
 *	On the first open of the device setup the port hardware, and
 *	initialize the per port data structure. Since initializing the port
 *	requires several commands to the board we will need to wait for any
 *	other open that is already initializing the port.
 */
	portp->tty = tty;
	tty->driver_data = portp;
	portp->refcount++;

	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_INITIALIZING, &portp->state));
	if (signal_pending(current))
		return(-ERESTARTSYS);

	if ((portp->flags & ASYNC_INITIALIZED) == 0) {
		set_bit(ST_INITIALIZING, &portp->state);
		if ((rc = stli_initopen(brdp, portp)) >= 0) {
			portp->flags |= ASYNC_INITIALIZED;
			clear_bit(TTY_IO_ERROR, &tty->flags);
		}
		clear_bit(ST_INITIALIZING, &portp->state);
		wake_up_interruptible(&portp->raw_wait);
		if (rc < 0)
			return(rc);
	}

/*
 *	Check if this port is in the middle of closing. If so then wait
 *	until it is closed then return error status, based on flag settings.
 *	The sleep here does not need interrupt protection since the wakeup
 *	for it is done with the same context.
 */
	if (portp->flags & ASYNC_CLOSING) {
		interruptible_sleep_on(&portp->close_wait);
		if (portp->flags & ASYNC_HUP_NOTIFY)
			return(-EAGAIN);
		return(-ERESTARTSYS);
	}

/*
 *	Based on type of open being done check if it can overlap with any
 *	previous opens still in effect. If we are a normal serial device
 *	then also we might have to wait for carrier.
 */
	if (!(filp->f_flags & O_NONBLOCK)) {
		if ((rc = stli_waitcarrier(brdp, portp, filp)) != 0)
			return(rc);
	}
	portp->flags |= ASYNC_NORMAL_ACTIVE;
	return(0);
}

/*****************************************************************************/

static void stli_close(struct tty_struct *tty, struct file *filp)
{
	stlibrd_t	*brdp;
	stliport_t	*portp;
	unsigned long	flags;

#ifdef DEBUG
	printk("stli_close(tty=%x,filp=%x)\n", (int) tty, (int) filp);
#endif

	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;

	save_flags(flags);
	cli();
	if (tty_hung_up_p(filp)) {
		restore_flags(flags);
		return;
	}
	if ((tty->count == 1) && (portp->refcount != 1))
		portp->refcount = 1;
	if (portp->refcount-- > 1) {
		restore_flags(flags);
		return;
	}

	portp->flags |= ASYNC_CLOSING;

/*
 *	May want to wait for data to drain before closing. The BUSY flag
 *	keeps track of whether we are still transmitting or not. It is
 *	updated by messages from the slave - indicating when all chars
 *	really have drained.
 */
	if (tty == stli_txcooktty)
		stli_flushchars(tty);
	tty->closing = 1;
	if (portp->closing_wait != ASYNC_CLOSING_WAIT_NONE)
		tty_wait_until_sent(tty, portp->closing_wait);

	portp->flags &= ~ASYNC_INITIALIZED;
	brdp = stli_brds[portp->brdnr];
	stli_rawclose(brdp, portp, 0, 0);
	if (tty->termios->c_cflag & HUPCL) {
		stli_mkasysigs(&portp->asig, 0, 0);
		if (test_bit(ST_CMDING, &portp->state))
			set_bit(ST_DOSIGS, &portp->state);
		else
			stli_sendcmd(brdp, portp, A_SETSIGNALS, &portp->asig,
				sizeof(asysigs_t), 0);
	}
	clear_bit(ST_TXBUSY, &portp->state);
	clear_bit(ST_RXSTOP, &portp->state);
	set_bit(TTY_IO_ERROR, &tty->flags);
	if (tty->ldisc.flush_buffer)
		(tty->ldisc.flush_buffer)(tty);
	set_bit(ST_DOFLUSHRX, &portp->state);
	stli_flushbuffer(tty);

	tty->closing = 0;
	portp->tty = (struct tty_struct *) NULL;

	if (portp->openwaitcnt) {
		if (portp->close_delay)
			msleep_interruptible(jiffies_to_msecs(portp->close_delay));
		wake_up_interruptible(&portp->open_wait);
	}

	portp->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
	wake_up_interruptible(&portp->close_wait);
	restore_flags(flags);
}

/*****************************************************************************/

/*
 *	Carry out first open operations on a port. This involves a number of
 *	commands to be sent to the slave. We need to open the port, set the
 *	notification events, set the initial port settings, get and set the
 *	initial signal values. We sleep and wait in between each one. But
 *	this still all happens pretty quickly.
 */

static int stli_initopen(stlibrd_t *brdp, stliport_t *portp)
{
	struct tty_struct	*tty;
	asynotify_t		nt;
	asyport_t		aport;
	int			rc;

#ifdef DEBUG
	printk("stli_initopen(brdp=%x,portp=%x)\n", (int) brdp, (int) portp);
#endif

	if ((rc = stli_rawopen(brdp, portp, 0, 1)) < 0)
		return(rc);

	memset(&nt, 0, sizeof(asynotify_t));
	nt.data = (DT_TXLOW | DT_TXEMPTY | DT_RXBUSY | DT_RXBREAK);
	nt.signal = SG_DCD;
	if ((rc = stli_cmdwait(brdp, portp, A_SETNOTIFY, &nt,
	    sizeof(asynotify_t), 0)) < 0)
		return(rc);

	tty = portp->tty;
	if (tty == (struct tty_struct *) NULL)
		return(-ENODEV);
	stli_mkasyport(portp, &aport, tty->termios);
	if ((rc = stli_cmdwait(brdp, portp, A_SETPORT, &aport,
	    sizeof(asyport_t), 0)) < 0)
		return(rc);

	set_bit(ST_GETSIGS, &portp->state);
	if ((rc = stli_cmdwait(brdp, portp, A_GETSIGNALS, &portp->asig,
	    sizeof(asysigs_t), 1)) < 0)
		return(rc);
	if (test_and_clear_bit(ST_GETSIGS, &portp->state))
		portp->sigs = stli_mktiocm(portp->asig.sigvalue);
	stli_mkasysigs(&portp->asig, 1, 1);
	if ((rc = stli_cmdwait(brdp, portp, A_SETSIGNALS, &portp->asig,
	    sizeof(asysigs_t), 0)) < 0)
		return(rc);

	return(0);
}

/*****************************************************************************/

/*
 *	Send an open message to the slave. This will sleep waiting for the
 *	acknowledgement, so must have user context. We need to co-ordinate
 *	with close events here, since we don't want open and close events
 *	to overlap.
 */

static int stli_rawopen(stlibrd_t *brdp, stliport_t *portp, unsigned long arg, int wait)
{
	volatile cdkhdr_t	*hdrp;
	volatile cdkctrl_t	*cp;
	volatile unsigned char	*bits;
	unsigned long		flags;
	int			rc;

#ifdef DEBUG
	printk("stli_rawopen(brdp=%x,portp=%x,arg=%x,wait=%d)\n",
		(int) brdp, (int) portp, (int) arg, wait);
#endif

/*
 *	Send a message to the slave to open this port.
 */
	save_flags(flags);
	cli();

/*
 *	Slave is already closing this port. This can happen if a hangup
 *	occurs on this port. So we must wait until it is complete. The
 *	order of opens and closes may not be preserved across shared
 *	memory, so we must wait until it is complete.
 */
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CLOSING, &portp->state));
	if (signal_pending(current)) {
		restore_flags(flags);
		return -ERESTARTSYS;
	}

/*
 *	Everything is ready now, so write the open message into shared
 *	memory. Once the message is in set the service bits to say that
 *	this port wants service.
 */
	EBRDENABLE(brdp);
	cp = &((volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr))->ctrl;
	cp->openarg = arg;
	cp->open = 1;
	hdrp = (volatile cdkhdr_t *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((volatile unsigned char *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	*bits |= portp->portbit;
	EBRDDISABLE(brdp);

	if (wait == 0) {
		restore_flags(flags);
		return(0);
	}

/*
 *	Slave is in action, so now we must wait for the open acknowledgment
 *	to come back.
 */
	rc = 0;
	set_bit(ST_OPENING, &portp->state);
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_OPENING, &portp->state));
	if (signal_pending(current))
		rc = -ERESTARTSYS;
	restore_flags(flags);

	if ((rc == 0) && (portp->rc != 0))
		rc = -EIO;
	return(rc);
}

/*****************************************************************************/

/*
 *	Send a close message to the slave. Normally this will sleep waiting
 *	for the acknowledgement, but if wait parameter is 0 it will not. If
 *	wait is true then must have user context (to sleep).
 */

static int stli_rawclose(stlibrd_t *brdp, stliport_t *portp, unsigned long arg, int wait)
{
	volatile cdkhdr_t	*hdrp;
	volatile cdkctrl_t	*cp;
	volatile unsigned char	*bits;
	unsigned long		flags;
	int			rc;

#ifdef DEBUG
	printk("stli_rawclose(brdp=%x,portp=%x,arg=%x,wait=%d)\n",
		(int) brdp, (int) portp, (int) arg, wait);
#endif

	save_flags(flags);
	cli();

/*
 *	Slave is already closing this port. This can happen if a hangup
 *	occurs on this port.
 */
	if (wait) {
		wait_event_interruptible(portp->raw_wait,
				!test_bit(ST_CLOSING, &portp->state));
		if (signal_pending(current)) {
			restore_flags(flags);
			return -ERESTARTSYS;
		}
	}

/*
 *	Write the close command into shared memory.
 */
	EBRDENABLE(brdp);
	cp = &((volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr))->ctrl;
	cp->closearg = arg;
	cp->close = 1;
	hdrp = (volatile cdkhdr_t *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((volatile unsigned char *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	*bits |= portp->portbit;
	EBRDDISABLE(brdp);

	set_bit(ST_CLOSING, &portp->state);
	if (wait == 0) {
		restore_flags(flags);
		return(0);
	}

/*
 *	Slave is in action, so now we must wait for the open acknowledgment
 *	to come back.
 */
	rc = 0;
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CLOSING, &portp->state));
	if (signal_pending(current))
		rc = -ERESTARTSYS;
	restore_flags(flags);

	if ((rc == 0) && (portp->rc != 0))
		rc = -EIO;
	return(rc);
}

/*****************************************************************************/

/*
 *	Send a command to the slave and wait for the response. This must
 *	have user context (it sleeps). This routine is generic in that it
 *	can send any type of command. Its purpose is to wait for that command
 *	to complete (as opposed to initiating the command then returning).
 */

static int stli_cmdwait(stlibrd_t *brdp, stliport_t *portp, unsigned long cmd, void *arg, int size, int copyback)
{
	unsigned long	flags;

#ifdef DEBUG
	printk("stli_cmdwait(brdp=%x,portp=%x,cmd=%x,arg=%x,size=%d,"
		"copyback=%d)\n", (int) brdp, (int) portp, (int) cmd,
		(int) arg, size, copyback);
#endif

	save_flags(flags);
	cli();
	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CMDING, &portp->state));
	if (signal_pending(current)) {
		restore_flags(flags);
		return -ERESTARTSYS;
	}

	stli_sendcmd(brdp, portp, cmd, arg, size, copyback);

	wait_event_interruptible(portp->raw_wait,
			!test_bit(ST_CMDING, &portp->state));
	if (signal_pending(current)) {
		restore_flags(flags);
		return -ERESTARTSYS;
	}
	restore_flags(flags);

	if (portp->rc != 0)
		return(-EIO);
	return(0);
}

/*****************************************************************************/

/*
 *	Send the termios settings for this port to the slave. This sleeps
 *	waiting for the command to complete - so must have user context.
 */

static int stli_setport(stliport_t *portp)
{
	stlibrd_t	*brdp;
	asyport_t	aport;

#ifdef DEBUG
	printk("stli_setport(portp=%x)\n", (int) portp);
#endif

	if (portp == (stliport_t *) NULL)
		return(-ENODEV);
	if (portp->tty == (struct tty_struct *) NULL)
		return(-ENODEV);
	if ((portp->brdnr < 0) && (portp->brdnr >= stli_nrbrds))
		return(-ENODEV);
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return(-ENODEV);

	stli_mkasyport(portp, &aport, portp->tty->termios);
	return(stli_cmdwait(brdp, portp, A_SETPORT, &aport, sizeof(asyport_t), 0));
}

/*****************************************************************************/

/*
 *	Possibly need to wait for carrier (DCD signal) to come high. Say
 *	maybe because if we are clocal then we don't need to wait...
 */

static int stli_waitcarrier(stlibrd_t *brdp, stliport_t *portp, struct file *filp)
{
	unsigned long	flags;
	int		rc, doclocal;

#ifdef DEBUG
	printk("stli_waitcarrier(brdp=%x,portp=%x,filp=%x)\n",
		(int) brdp, (int) portp, (int) filp);
#endif

	rc = 0;
	doclocal = 0;

	if (portp->tty->termios->c_cflag & CLOCAL)
		doclocal++;

	save_flags(flags);
	cli();
	portp->openwaitcnt++;
	if (! tty_hung_up_p(filp))
		portp->refcount--;

	for (;;) {
		stli_mkasysigs(&portp->asig, 1, 1);
		if ((rc = stli_cmdwait(brdp, portp, A_SETSIGNALS,
		    &portp->asig, sizeof(asysigs_t), 0)) < 0)
			break;
		if (tty_hung_up_p(filp) ||
		    ((portp->flags & ASYNC_INITIALIZED) == 0)) {
			if (portp->flags & ASYNC_HUP_NOTIFY)
				rc = -EBUSY;
			else
				rc = -ERESTARTSYS;
			break;
		}
		if (((portp->flags & ASYNC_CLOSING) == 0) &&
		    (doclocal || (portp->sigs & TIOCM_CD))) {
			break;
		}
		if (signal_pending(current)) {
			rc = -ERESTARTSYS;
			break;
		}
		interruptible_sleep_on(&portp->open_wait);
	}

	if (! tty_hung_up_p(filp))
		portp->refcount++;
	portp->openwaitcnt--;
	restore_flags(flags);

	return(rc);
}

/*****************************************************************************/

/*
 *	Write routine. Take the data and put it in the shared memory ring
 *	queue. If port is not already sending chars then need to mark the
 *	service bits for this port.
 */

static int stli_write(struct tty_struct *tty, const unsigned char *buf, int count)
{
	volatile cdkasy_t	*ap;
	volatile cdkhdr_t	*hdrp;
	volatile unsigned char	*bits;
	unsigned char		*shbuf, *chbuf;
	stliport_t		*portp;
	stlibrd_t		*brdp;
	unsigned int		len, stlen, head, tail, size;
	unsigned long		flags;

#ifdef DEBUG
	printk("stli_write(tty=%x,buf=%x,count=%d)\n",
		(int) tty, (int) buf, count);
#endif

	if ((tty == (struct tty_struct *) NULL) ||
	    (stli_tmpwritebuf == (char *) NULL))
		return(0);
	if (tty == stli_txcooktty)
		stli_flushchars(tty);
	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return(0);
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return(0);
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return(0);
	chbuf = (unsigned char *) buf;

/*
 *	All data is now local, shove as much as possible into shared memory.
 */
	save_flags(flags);
	cli();
	EBRDENABLE(brdp);
	ap = (volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr);
	head = (unsigned int) ap->txq.head;
	tail = (unsigned int) ap->txq.tail;
	if (tail != ((unsigned int) ap->txq.tail))
		tail = (unsigned int) ap->txq.tail;
	size = portp->txsize;
	if (head >= tail) {
		len = size - (head - tail) - 1;
		stlen = size - head;
	} else {
		len = tail - head - 1;
		stlen = len;
	}

	len = MIN(len, count);
	count = 0;
	shbuf = (char *) EBRDGETMEMPTR(brdp, portp->txoffset);

	while (len > 0) {
		stlen = MIN(len, stlen);
		memcpy((shbuf + head), chbuf, stlen);
		chbuf += stlen;
		len -= stlen;
		count += stlen;
		head += stlen;
		if (head >= size) {
			head = 0;
			stlen = tail;
		}
	}

	ap = (volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr);
	ap->txq.head = head;
	if (test_bit(ST_TXBUSY, &portp->state)) {
		if (ap->changed.data & DT_TXEMPTY)
			ap->changed.data &= ~DT_TXEMPTY;
	}
	hdrp = (volatile cdkhdr_t *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((volatile unsigned char *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	*bits |= portp->portbit;
	set_bit(ST_TXBUSY, &portp->state);
	EBRDDISABLE(brdp);

	restore_flags(flags);

	return(count);
}

/*****************************************************************************/

/*
 *	Output a single character. We put it into a temporary local buffer
 *	(for speed) then write out that buffer when the flushchars routine
 *	is called. There is a safety catch here so that if some other port
 *	writes chars before the current buffer has been, then we write them
 *	first them do the new ports.
 */

static void stli_putchar(struct tty_struct *tty, unsigned char ch)
{
#ifdef DEBUG
	printk("stli_putchar(tty=%x,ch=%x)\n", (int) tty, (int) ch);
#endif

	if (tty == (struct tty_struct *) NULL)
		return;
	if (tty != stli_txcooktty) {
		if (stli_txcooktty != (struct tty_struct *) NULL)
			stli_flushchars(stli_txcooktty);
		stli_txcooktty = tty;
	}

	stli_txcookbuf[stli_txcooksize++] = ch;
}

/*****************************************************************************/

/*
 *	Transfer characters from the local TX cooking buffer to the board.
 *	We sort of ignore the tty that gets passed in here. We rely on the
 *	info stored with the TX cook buffer to tell us which port to flush
 *	the data on. In any case we clean out the TX cook buffer, for re-use
 *	by someone else.
 */

static void stli_flushchars(struct tty_struct *tty)
{
	volatile cdkhdr_t	*hdrp;
	volatile unsigned char	*bits;
	volatile cdkasy_t	*ap;
	struct tty_struct	*cooktty;
	stliport_t		*portp;
	stlibrd_t		*brdp;
	unsigned int		len, stlen, head, tail, size, count, cooksize;
	unsigned char		*buf, *shbuf;
	unsigned long		flags;

#ifdef DEBUG
	printk("stli_flushchars(tty=%x)\n", (int) tty);
#endif

	cooksize = stli_txcooksize;
	cooktty = stli_txcooktty;
	stli_txcooksize = 0;
	stli_txcookrealsize = 0;
	stli_txcooktty = (struct tty_struct *) NULL;

	if (tty == (struct tty_struct *) NULL)
		return;
	if (cooktty == (struct tty_struct *) NULL)
		return;
	if (tty != cooktty)
		tty = cooktty;
	if (cooksize == 0)
		return;

	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return;
	if ((portp->brdnr < 0) || (portp->brdnr >= stli_nrbrds))
		return;
	brdp = stli_brds[portp->brdnr];
	if (brdp == (stlibrd_t *) NULL)
		return;

	save_flags(flags);
	cli();
	EBRDENABLE(brdp);

	ap = (volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr);
	head = (unsigned int) ap->txq.head;
	tail = (unsigned int) ap->txq.tail;
	if (tail != ((unsigned int) ap->txq.tail))
		tail = (unsigned int) ap->txq.tail;
	size = portp->txsize;
	if (head >= tail) {
		len = size - (head - tail) - 1;
		stlen = size - head;
	} else {
		len = tail - head - 1;
		stlen = len;
	}

	len = MIN(len, cooksize);
	count = 0;
	shbuf = (char *) EBRDGETMEMPTR(brdp, portp->txoffset);
	buf = stli_txcookbuf;

	while (len > 0) {
		stlen = MIN(len, stlen);
		memcpy((shbuf + head), buf, stlen);
		buf += stlen;
		len -= stlen;
		count += stlen;
		head += stlen;
		if (head >= size) {
			head = 0;
			stlen = tail;
		}
	}

	ap = (volatile cdkasy_t *) EBRDGETMEMPTR(brdp, portp->addr);
	ap->txq.head = head;

	if (test_bit(ST_TXBUSY, &portp->state)) {
		if (ap->changed.data & DT_TXEMPTY)
			ap->changed.data &= ~DT_TXEMPTY;
	}
	hdrp = (volatile cdkhdr_t *) EBRDGETMEMPTR(brdp, CDK_CDKADDR);
	bits = ((volatile unsigned char *) hdrp) + brdp->slaveoffset +
		portp->portidx;
	*bits |= portp->portbit;
	set_bit(ST_TXBUSY, &portp->state);

	EBRDDISABLE(brdp);
	restore_flags(flags);
}

/*****************************************************************************/

static int stli_writeroom(struct tty_struct *tty)
{
	volatile cdkasyrq_t	*rp;
	stliport_t		*portp;
	stlibrd_t		*brdp;
	unsigned int		head, tail, len;
	unsigned long		flags;

#ifdef DEBUG
	printk("stli_writeroom(tty=%x)\n", (int) tty);
#endif

	if (tty == (struct tty_struct *) NULL)
		return(0);
	if (tty == stli_txcooktty) {
		if (stli_txcookrealsize != 0) {
			len = stli_txcookrealsize - stli_txcooksize;
			return(len);
		}
	}

	portp = tty->driver_data;
	if (portp == (stliport_t *) NULL)
		return(0);
	if ((portp->brdnr <…