drivers/staging/dgap/dgap_sysfs.c

/*
 * Copyright 2004 Digi International (www.digi.com)
 *      Scott H Kilau <Scott_Kilau at digi dot com>
 * 
 * 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, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY, EXPRESS OR IMPLIED; 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.
 *
 * 
 *      NOTE TO LINUX KERNEL HACKERS:  DO NOT REFORMAT THIS CODE!
 *
 *      This is shared code between Digi's CVS archive and the
 *      Linux Kernel sources.
 *      Changing the source just for reformatting needlessly breaks
 *      our CVS diff history.
 *
 *      Send any bug fixes/changes to:  Eng.Linux at digi dot com.
 *      Thank you.
 *
 *
 * 
 * $Id: dgap_sysfs.c,v 1.1 2009/10/23 14:01:57 markh Exp $   
 */


#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/ctype.h>
#include <linux/string.h>
#include <linux/serial_reg.h>
#include <linux/device.h>
#include <linux/pci.h>
#include <linux/kdev_t.h>
  
#include "dgap_driver.h"
#include "dgap_conf.h"
#include "dgap_parse.h"


static ssize_t dgap_driver_version_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%s\n", DG_PART);
}
static DRIVER_ATTR(version, S_IRUSR, dgap_driver_version_show, NULL);


static ssize_t dgap_driver_boards_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", dgap_NumBoards);
}
static DRIVER_ATTR(boards, S_IRUSR, dgap_driver_boards_show, NULL);


static ssize_t dgap_driver_maxboards_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%d\n", MAXBOARDS);
}
static DRIVER_ATTR(maxboards, S_IRUSR, dgap_driver_maxboards_show, NULL);


static ssize_t dgap_driver_pollcounter_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%ld\n", dgap_poll_counter);
}
static DRIVER_ATTR(pollcounter, S_IRUSR, dgap_driver_pollcounter_show, NULL);


static ssize_t dgap_driver_state_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%s\n", dgap_driver_state_text[dgap_driver_state]);
}
static DRIVER_ATTR(state, S_IRUSR, dgap_driver_state_show, NULL);


static ssize_t dgap_driver_debug_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "0x%x\n", dgap_debug);
}

static ssize_t dgap_driver_debug_store(struct device_driver *ddp, const char *buf, size_t count)
{
	sscanf(buf, "0x%x\n", &dgap_debug);
	return count;
}
static DRIVER_ATTR(debug, (S_IRUSR | S_IWUSR), dgap_driver_debug_show, dgap_driver_debug_store);


static ssize_t dgap_driver_rawreadok_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "0x%x\n", dgap_rawreadok);
}

static ssize_t dgap_driver_rawreadok_store(struct device_driver *ddp, const char *buf, size_t count)
{
	sscanf(buf, "0x%x\n", &dgap_rawreadok);
	return count;
}
static DRIVER_ATTR(rawreadok, (S_IRUSR | S_IWUSR), dgap_driver_rawreadok_show, dgap_driver_rawreadok_store);


static ssize_t dgap_driver_pollrate_show(struct device_driver *ddp, char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%dms\n", dgap_poll_tick);
}

static ssize_t dgap_driver_pollrate_store(struct device_driver *ddp, const char *buf, size_t count)
{
	sscanf(buf, "%d\n", &dgap_poll_tick);
	return count;
}
static DRIVER_ATTR(pollrate, (S_IRUSR | S_IWUSR), dgap_driver_pollrate_show, dgap_driver_pollrate_store);


void dgap_create_driver_sysfiles(struct pci_driver *dgap_driver)
{
	int rc = 0;
	struct device_driver *driverfs = &dgap_driver->driver;

	rc |= driver_create_file(driverfs, &driver_attr_version);
	rc |= driver_create_file(driverfs, &driver_attr_boards);
	rc |= driver_create_file(driverfs, &driver_attr_maxboards);
	rc |= driver_create_file(driverfs, &driver_attr_debug);
	rc |= driver_create_file(driverfs, &driver_attr_rawreadok); 
	rc |= driver_create_file(driverfs, &driver_attr_pollrate);
	rc |= driver_create_file(driverfs, &driver_attr_pollcounter);
	rc |= driver_create_file(driverfs, &driver_attr_state);
	if (rc) {
		printk(KERN_ERR "DGAP: sysfs driver_create_file failed!\n");
	}
}


void dgap_remove_driver_sysfiles(struct pci_driver *dgap_driver)
{
	struct device_driver *driverfs = &dgap_driver->driver;
	driver_remove_file(driverfs, &driver_attr_version);
	driver_remove_file(driverfs, &driver_attr_boards);
	driver_remove_file(driverfs, &driver_attr_maxboards);
	driver_remove_file(driverfs, &driver_attr_debug);
	driver_remove_file(driverfs, &driver_attr_rawreadok);
	driver_remove_file(driverfs, &driver_attr_pollrate);
	driver_remove_file(driverfs, &driver_attr_pollcounter);
	driver_remove_file(driverfs, &driver_attr_state);
}


#define DGAP_VERIFY_BOARD(p, bd)			\
	if (!p)						\
		return (0);				\
							\
	bd = dev_get_drvdata(p);			\
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)	\
		return (0);				\
	if (bd->state != BOARD_READY)			\
		return (0);				\


static ssize_t dgap_ports_state_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count,
			"%d %s\n", bd->channels[i]->ch_portnum,
			bd->channels[i]->ch_open_count ? "Open" : "Closed");
	}
	return count;
}
static DEVICE_ATTR(ports_state, S_IRUSR, dgap_ports_state_show, NULL);


static ssize_t dgap_ports_baud_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count +=  snprintf(buf + count, PAGE_SIZE - count,
			"%d %d\n", bd->channels[i]->ch_portnum, bd->channels[i]->ch_baud_info);
	}
	return count;
}
static DEVICE_ATTR(ports_baud, S_IRUSR, dgap_ports_baud_show, NULL);


static ssize_t dgap_ports_msignals_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		if (bd->channels[i]->ch_open_count) {
			count += snprintf(buf + count, PAGE_SIZE - count,
				"%d %s %s %s %s %s %s\n", bd->channels[i]->ch_portnum,
				(bd->channels[i]->ch_mostat & UART_MCR_RTS) ? "RTS" : "",
				(bd->channels[i]->ch_mistat & UART_MSR_CTS) ? "CTS" : "",
				(bd->channels[i]->ch_mostat & UART_MCR_DTR) ? "DTR" : "",
				(bd->channels[i]->ch_mistat & UART_MSR_DSR) ? "DSR" : "",
				(bd->channels[i]->ch_mistat & UART_MSR_DCD) ? "DCD" : "",
				(bd->channels[i]->ch_mistat & UART_MSR_RI)  ? "RI"  : "");
		} else {
			count += snprintf(buf + count, PAGE_SIZE - count,
				"%d\n", bd->channels[i]->ch_portnum);
		}
	}
	return count;
}
static DEVICE_ATTR(ports_msignals, S_IRUSR, dgap_ports_msignals_show, NULL);


static ssize_t dgap_ports_iflag_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %x\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_c_iflag);
	}
	return count;
}
static DEVICE_ATTR(ports_iflag, S_IRUSR, dgap_ports_iflag_show, NULL);


static ssize_t dgap_ports_cflag_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %x\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_c_cflag);
	}
	return count;
}
static DEVICE_ATTR(ports_cflag, S_IRUSR, dgap_ports_cflag_show, NULL);


static ssize_t dgap_ports_oflag_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %x\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_c_oflag);
	}
	return count;
}
static DEVICE_ATTR(ports_oflag, S_IRUSR, dgap_ports_oflag_show, NULL);


static ssize_t dgap_ports_lflag_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %x\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_c_lflag);
	}
	return count;
}
static DEVICE_ATTR(ports_lflag, S_IRUSR, dgap_ports_lflag_show, NULL);


static ssize_t dgap_ports_digi_flag_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %x\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_digi.digi_flags);
	}
	return count;
}
static DEVICE_ATTR(ports_digi_flag, S_IRUSR, dgap_ports_digi_flag_show, NULL);


static ssize_t dgap_ports_rxcount_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %ld\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_rxcount);
	}
	return count;
}
static DEVICE_ATTR(ports_rxcount, S_IRUSR, dgap_ports_rxcount_show, NULL);


static ssize_t dgap_ports_txcount_show(struct device *p, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	int count = 0;
	int i = 0;

	DGAP_VERIFY_BOARD(p, bd);

	for (i = 0; i < bd->nasync; i++) {
		count += snprintf(buf + count, PAGE_SIZE - count, "%d %ld\n",
			bd->channels[i]->ch_portnum, bd->channels[i]->ch_txcount);
	}
	return count;
}
static DEVICE_ATTR(ports_txcount, S_IRUSR, dgap_ports_txcount_show, NULL);


/* this function creates the sys files that will export each signal status
 * to sysfs each value will be put in a separate filename
 */
void dgap_create_ports_sysfiles(struct board_t *bd)
{
	int rc = 0;

	dev_set_drvdata(&bd->pdev->dev, bd);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_state);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_baud);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_msignals);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_iflag);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_cflag);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_oflag);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_lflag);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_digi_flag);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_rxcount);
	rc |= device_create_file(&(bd->pdev->dev), &dev_attr_ports_txcount);
	if (rc) {
		printk(KERN_ERR "DGAP: sysfs device_create_file failed!\n");
	}
}


/* removes all the sys files created for that port */
void dgap_remove_ports_sysfiles(struct board_t *bd)
{
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_state);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_baud);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_msignals);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_iflag);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_cflag);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_oflag);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_lflag);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_digi_flag);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_rxcount);
	device_remove_file(&(bd->pdev->dev), &dev_attr_ports_txcount);
}


static ssize_t dgap_tty_state_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%s", un->un_open_count ? "Open" : "Closed");
}
static DEVICE_ATTR(state, S_IRUSR, dgap_tty_state_show, NULL);


static ssize_t dgap_tty_baud_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%d\n", ch->ch_baud_info);
}
static DEVICE_ATTR(baud, S_IRUSR, dgap_tty_baud_show, NULL);


static ssize_t dgap_tty_msignals_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	if (ch->ch_open_count) {
		return snprintf(buf, PAGE_SIZE, "%s %s %s %s %s %s\n",
			(ch->ch_mostat & UART_MCR_RTS) ? "RTS" : "",
			(ch->ch_mistat & UART_MSR_CTS) ? "CTS" : "",
			(ch->ch_mostat & UART_MCR_DTR) ? "DTR" : "",
			(ch->ch_mistat & UART_MSR_DSR) ? "DSR" : "",
			(ch->ch_mistat & UART_MSR_DCD) ? "DCD" : "",
			(ch->ch_mistat & UART_MSR_RI)  ? "RI"  : "");
	}
	return 0;
}
static DEVICE_ATTR(msignals, S_IRUSR, dgap_tty_msignals_show, NULL);


static ssize_t dgap_tty_iflag_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%x\n", ch->ch_c_iflag);
}
static DEVICE_ATTR(iflag, S_IRUSR, dgap_tty_iflag_show, NULL);


static ssize_t dgap_tty_cflag_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%x\n", ch->ch_c_cflag);
}
static DEVICE_ATTR(cflag, S_IRUSR, dgap_tty_cflag_show, NULL);


static ssize_t dgap_tty_oflag_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%x\n", ch->ch_c_oflag);
}
static DEVICE_ATTR(oflag, S_IRUSR, dgap_tty_oflag_show, NULL);


static ssize_t dgap_tty_lflag_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%x\n", ch->ch_c_lflag);
}
static DEVICE_ATTR(lflag, S_IRUSR, dgap_tty_lflag_show, NULL);


static ssize_t dgap_tty_digi_flag_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%x\n", ch->ch_digi.digi_flags);
}
static DEVICE_ATTR(digi_flag, S_IRUSR, dgap_tty_digi_flag_show, NULL);


static ssize_t dgap_tty_rxcount_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%ld\n", ch->ch_rxcount);
}
static DEVICE_ATTR(rxcount, S_IRUSR, dgap_tty_rxcount_show, NULL);


static ssize_t dgap_tty_txcount_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

	return snprintf(buf, PAGE_SIZE, "%ld\n", ch->ch_txcount);
}
static DEVICE_ATTR(txcount, S_IRUSR, dgap_tty_txcount_show, NULL);


static ssize_t dgap_tty_name_show(struct device *d, struct device_attribute *attr, char *buf)
{
	struct board_t *bd;
	struct channel_t *ch;
	struct un_t *un;
	int	cn;
	int	bn;
	struct cnode *cptr = NULL;
	int found = FALSE;
	int ncount = 0;
	int starto = 0;
	int i = 0;

	if (!d)
		return (0);
	un = dev_get_drvdata(d);
	if (!un || un->magic != DGAP_UNIT_MAGIC)
		return (0);
	ch = un->un_ch;
	if (!ch || ch->magic != DGAP_CHANNEL_MAGIC)
		return (0);
	bd = ch->ch_bd;
	if (!bd || bd->magic != DGAP_BOARD_MAGIC)
		return (0);
	if (bd->state != BOARD_READY)
		return (0);

        bn = bd->boardnum;
	cn = ch->ch_portnum;

	for (cptr = bd->bd_config; cptr; cptr = cptr->next) {

		if ((cptr->type == BNODE) &&
		    ((cptr->u.board.type == APORT2_920P) || (cptr->u.board.type == APORT4_920P) ||
		     (cptr->u.board.type == APORT8_920P) || (cptr->u.board.type == PAPORT4) ||
		     (cptr->u.board.type == PAPORT8))) {

				found = TRUE;
				if (cptr->u.board.v_start)
					starto = cptr->u.board.start;
				else
					starto = 1;
		}

		if (cptr->type == TNODE && found == TRUE) {
			char *ptr1;
			if (strstr(cptr->u.ttyname, "tty")) {
				ptr1 = cptr->u.ttyname;
				ptr1 += 3;
			}
			else {
				ptr1 = cptr->u.ttyname;
			}

			for (i = 0; i < dgap_config_get_number_of_ports(bd); i++) {
				if (cn == i) {
					return snprintf(buf, PAGE_SIZE, "%s%s%02d\n",
						(un->un_type == DGAP_PRINT) ? "pr" : "tty",
						ptr1, i + starto);
				}
			}
		}

		if (cptr->type == CNODE) {

			for (i = 0; i < cptr->u.conc.nport; i++) {
				if (cn == (i + ncount)) {

					return snprintf(buf, PAGE_SIZE, "%s%s%02d\n",
						(un->un_type == DGAP_PRINT) ? "pr" : "tty",
						cptr->u.conc.id,
						i + (cptr->u.conc.v_start ? cptr->u.conc.start : 1));
				}
			}

			ncount += cptr->u.conc.nport;
		}

		if (cptr->type == MNODE) {

			for (i = 0; i < cptr->u.module.nport; i++) {
				if (cn == (i + ncount)) {
					return snprintf(buf, PAGE_SIZE, "%s%s%02d\n",
						(un->un_type == DGAP_PRINT) ? "pr" : "tty",
						cptr->u.module.id,
						i + (cptr->u.module.v_start ? cptr->u.module.start : 1));
				}
			}

			ncount += cptr->u.module.nport;

		}
	}

	return snprintf(buf, PAGE_SIZE, "%s_dgap_%d_%d\n",
		(un->un_type == DGAP_PRINT) ? "pr" : "tty", bn, cn);

}
static DEVICE_ATTR(custom_name, S_IRUSR, dgap_tty_name_show, NULL);


static struct attribute *dgap_sysfs_tty_entries[] = {
	&dev_attr_state.attr,
	&dev_attr_baud.attr,
	&dev_attr_msignals.attr,
	&dev_attr_iflag.attr,
	&dev_attr_cflag.attr,
	&dev_attr_oflag.attr,
	&dev_attr_lflag.attr,
	&dev_attr_digi_flag.attr,
	&dev_attr_rxcount.attr,
	&dev_attr_txcount.attr,
	&dev_attr_custom_name.attr,
	NULL
};


static struct attribute_group dgap_tty_attribute_group = {
	.name = NULL,
	.attrs = dgap_sysfs_tty_entries,
};




void dgap_create_tty_sysfs(struct un_t *un, struct device *c)
{
	int ret;

	ret = sysfs_create_group(&c->kobj, &dgap_tty_attribute_group);
	if (ret) {
		printk(KERN_ERR "dgap: failed to create sysfs tty device attributes.\n");
		sysfs_remove_group(&c->kobj, &dgap_tty_attribute_group);
		return;
	}

	dev_set_drvdata(c, un);

}


void dgap_remove_tty_sysfs(struct device *c)
{
	sysfs_remove_group(&c->kobj, &dgap_tty_attribute_group);
}