icn.c

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/* $Id: icn.c,v 1.65 2000/11/13 22:51:48 kai Exp $

 * ISDN low-level module for the ICN active ISDN-Card.
 *
 * Copyright 1994,95,96 by Fritz Elfert ([e-mail])
 *
 * 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; 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 "icn.h"

/*
 * Verbose bootcode- and protocol-downloading.
 */
#undef BOOT_DEBUG

/*
 * Verbose Shmem-Mapping.
 */
#undef MAP_DEBUG

static char
*revision = "$Revision: 1.65 $";

static int icn_addcard(int, char *, char *);

/*
 * Free send-queue completely.
 * Parameter:
 *   card   = pointer to card struct
 *   channel = channel number
 */
static void
icn_free_queue(icn_card * card, int channel)
{
	struct sk_buff_head *queue = &card->spqueue[channel];
	struct sk_buff *skb;
	unsigned long flags;

	while ((skb = skb_dequeue(queue)))
		dev_kfree_skb(skb);
	save_flags(flags);
	cli();
	card->xlen[channel] = 0;
	card->sndcount[channel] = 0;
	if ((skb = card->xskb[channel])) {
		card->xskb[channel] = NULL;
		restore_flags(flags);
		dev_kfree_skb(skb);
	} else
		restore_flags(flags);
}

/* Put a value into a shift-register, highest bit first.
 * Parameters:
 *            port     = port for output (bit 0 is significant)
 *            val      = value to be output
 *            firstbit = Bit-Number of highest bit
 *            bitcount = Number of bits to output
 */
static inline void
icn_shiftout(unsigned short port,
	     unsigned long val,
	     int firstbit,
	     int bitcount)
{

	register u_char s;
	register u_char c;

	for (s = firstbit, c = bitcount; c > 0; s--, c--)
		OUTB_P((u_char) ((val >> s) & 1) ? 0xff : 0, port);
}

/*
 * disable a cards shared memory
 */
static inline void
icn_disable_ram(icn_card * card)
{
	OUTB_P(0, ICN_MAPRAM);
}

/*
 * enable a cards shared memory
 */
static inline void
icn_enable_ram(icn_card * card)
{
	OUTB_P(0xff, ICN_MAPRAM);
}

/*
 * Map a cards channel0 (Bank0/Bank8) or channel1 (Bank4/Bank12)
 */
static inline void
icn_map_channel(icn_card * card, int channel)
{
#ifdef MAP_DEBUG
	printk(KERN_DEBUG "icn_map_channel %d %d\n", dev.channel, channel);
#endif
	if ((channel == dev.channel) && (card == dev.mcard))
		return;
	if (dev.mcard)
		icn_disable_ram(dev.mcard);
	icn_shiftout(ICN_BANK, chan2bank[channel], 3, 4);	/* Select Bank          */
	icn_enable_ram(card);
	dev.mcard = card;
	dev.channel = channel;
#ifdef MAP_DEBUG
	printk(KERN_DEBUG "icn_map_channel done\n");
#endif
}

/*
 * Lock a cards channel.
 * Return 0 if requested card/channel is unmapped (failure).
 * Return 1 on success.
 */
static inline int
icn_lock_channel(icn_card * card, int channel)
{
	register int retval;
	ulong flags;

#ifdef MAP_DEBUG
	printk(KERN_DEBUG "icn_lock_channel %d\n", channel);
#endif
	save_flags(flags);
	cli();
	if ((dev.channel == channel) && (card == dev.mcard)) {
		dev.chanlock++;
		retval = 1;
#ifdef MAP_DEBUG
		printk(KERN_DEBUG "icn_lock_channel %d OK\n", channel);
#endif
	} else {
		retval = 0;
#ifdef MAP_DEBUG
		printk(KERN_DEBUG "icn_lock_channel %d FAILED, dc=%d\n", channel, dev.channel);
#endif
	}
	restore_flags(flags);
	return retval;
}

/*
 * Release current card/channel lock
 */
static inline void
icn_release_channel(void)
{
	ulong flags;

#ifdef MAP_DEBUG
	printk(KERN_DEBUG "icn_release_channel l=%d\n", dev.chanlock);
#endif
	save_flags(flags);
	cli();
	if (dev.chanlock > 0)
		dev.chanlock--;
	restore_flags(flags);
}

/*
 * Try to map and lock a cards channel.
 * Return 1 on success, 0 on failure.
 */
static inline int
icn_trymaplock_channel(icn_card * card, int channel)
{
	ulong flags;

#ifdef MAP_DEBUG
	printk(KERN_DEBUG "trymaplock c=%d dc=%d l=%d\n", channel, dev.channel,
	       dev.chanlock);
#endif
	save_flags(flags);
	cli();
	if ((!dev.chanlock) ||
	    ((dev.channel == channel) && (dev.mcard == card))) {
		dev.chanlock++;
		icn_map_channel(card, channel);
		restore_flags(flags);
#ifdef MAP_DEBUG
		printk(KERN_DEBUG "trymaplock %d OK\n", channel);
#endif
		return 1;
	}
	restore_flags(flags);
#ifdef MAP_DEBUG
	printk(KERN_DEBUG "trymaplock %d FAILED\n", channel);
#endif
	return 0;
}

/*
 * Release current card/channel lock,
 * then map same or other channel without locking.
 */
static inline void
icn_maprelease_channel(icn_card * card, int channel)
{
	ulong flags;

#ifdef MAP_DEBUG
	printk(KERN_DEBUG "map_release c=%d l=%d\n", channel, dev.chanlock);
#endif
	save_flags(flags);
	cli();
	if (dev.chanlock > 0)
		dev.chanlock--;
	if (!dev.chanlock)
		icn_map_channel(card, channel);
	restore_flags(flags);
}

/* Get Data from the B-Channel, assemble fragmented packets and put them
 * into receive-queue. Wake up any B-Channel-reading processes.
 * This routine is called via timer-callback from icn_pollbchan().
 */

static void
icn_pollbchan_receive(int channel, icn_card * card)
{
	int mch = channel + ((card->secondhalf) ? 2 : 0);
	int eflag;
	int cnt;
	struct sk_buff *skb;

	if (icn_trymaplock_channel(card, mch)) {
		while (rbavl) {
			cnt = readb(&rbuf_l);
			if ((card->rcvidx[channel] + cnt) > 4000) {
				printk(KERN_WARNING
				       "icn: (%s) bogus packet on ch%d, dropping.\n",
				       CID,
				       channel + 1);
				card->rcvidx[channel] = 0;
				eflag = 0;
			} else {
				memcpy_fromio(&card->rcvbuf[channel][card->rcvidx[channel]],
					      &rbuf_d, cnt);
				card->rcvidx[channel] += cnt;
				eflag = readb(&rbuf_f);
			}
			rbnext;
			icn_maprelease_channel(card, mch & 2);
			if (!eflag) {
				if ((cnt = card->rcvidx[channel])) {
					if (!(skb = dev_alloc_skb(cnt))) {
						printk(KERN_WARNING "icn: receive out of memory\n");
						break;
					}
					memcpy(skb_put(skb, cnt), card->rcvbuf[channel], cnt);
					card->rcvidx[channel] = 0;
					card->interface.rcvcallb_skb(card->myid, channel, skb);
				}
			}
			if (!icn_trymaplock_channel(card, mch))
				break;
		}
		icn_maprelease_channel(card, mch & 2);
	}
}

/* Send data-packet to B-Channel, split it up into fragments of
 * ICN_FRAGSIZE length. If last fragment is sent out, signal
 * success to upper layers via statcallb with ISDN_STAT_BSENT argument.
 * This routine is called via timer-callback from icn_pollbchan() or
 * directly from icn_sendbuf().
 */

static void
icn_pollbchan_send(int channel, icn_card * card)
{
	int mch = channel + ((card->secondhalf) ? 2 : 0);
	int cnt;
	unsigned long flags;
	struct sk_buff *skb;
	isdn_ctrl cmd;

	if (!(card->sndcount[channel] || card->xskb[channel] ||
	      skb_queue_len(&card->spqueue[channel])))
		return;
	if (icn_trymaplock_channel(card, mch)) {
		while (sbfree && 
		       (card->sndcount[channel] ||
			skb_queue_len(&card->spqueue[channel]) ||
			card->xskb[channel])) {
			save_flags(flags);
			cli();
			if (card->xmit_lock[channel]) {
				restore_flags(flags);
				break;
			}
			card->xmit_lock[channel]++;
			restore_flags(flags);
			skb = card->xskb[channel];
			if (!skb) {
				skb = skb_dequeue(&card->spqueue[channel]);
				if (skb) {
					/* Pop ACK-flag off skb.
					 * Store length to xlen.
					 */
					if (*(skb_pull(skb,1)))
						card->xlen[channel] = skb->len;
					else
						card->xlen[channel] = 0;
				}
			}
			if (!skb)
				break;
			if (skb->len > ICN_FRAGSIZE) {
				writeb(0xff, &sbuf_f);
				cnt = ICN_FRAGSIZE;
			} else {
				writeb(0x0, &sbuf_f);
				cnt = skb->len;
			}
			writeb(cnt, &sbuf_l);
			memcpy_toio(&sbuf_d, skb->data, cnt);
			skb_pull(skb, cnt);
			card->sndcount[channel] -= cnt;
			sbnext; /* switch to next buffer        */
			icn_maprelease_channel(card, mch & 2);
			if (!skb->len) {
				save_flags(flags);
				cli();
				if (card->xskb[channel])
					card->xskb[channel] = NULL;
				restore_flags(flags);
				dev_kfree_skb(skb);
				if (card->xlen[channel]) {
					cmd.command = ISDN_STAT_BSENT;
					cmd.driver = card->myid;
					cmd.arg = channel;
					cmd.parm.length = card->xlen[channel];
					card->interface.statcallb(&cmd);
				}
			} else {
				save_flags(flags);
				cli();
				card->xskb[channel] = skb;
				restore_flags(flags);
			}
			card->xmit_lock[channel] = 0;
			if (!icn_trymaplock_channel(card, mch))
				break;
		}
		icn_maprelease_channel(card, mch & 2);
	}
}

/* Send/Receive Data to/from the B-Channel.
 * This routine is called via timer-callback.
 * It schedules itself while any B-Channel is open.
 */

static void
icn_pollbchan(unsigned long data)
{
	icn_card *card = (icn_card *) data;
	unsigned long flags;

	if (card->flags & ICN_FLAGS_B1ACTIVE) {
		icn_pollbchan_receive(0, card);
		icn_pollbchan_send(0, card);
	}
	if (card->flags & ICN_FLAGS_B2ACTIVE) {
		icn_pollbchan_receive(1, card);
		icn_pollbchan_send(1, card);
	}
	if (card->flags & (ICN_FLAGS_B1ACTIVE | ICN_FLAGS_B2ACTIVE)) {
		/* schedule b-channel polling again */
		save_flags(flags);
		cli();
		mod_timer(&card->rb_timer, jiffies+ICN_TIMER_BCREAD);
		card->flags |= ICN_FLAGS_RBTIMER;
		restore_flags(flags);
	} else
		card->flags &= ~ICN_FLAGS_RBTIMER;
}

typedef struct icn_stat {
	char *statstr;
	int command;
	int action;
} icn_stat;
/* *INDENT-OFF* */
static icn_stat icn_stat_table[] =
{
	{"BCON_",          ISDN_STAT_BCONN, 1},	/* B-Channel connected        */
	{"BDIS_",          ISDN_STAT_BHUP,  2},	/* B-Channel disconnected     */
	/*
	** add d-channel connect and disconnect support to link-level
	*/
	{"DCON_",          ISDN_STAT_DCONN, 10},	/* D-Channel connected        */
	{"DDIS_",          ISDN_STAT_DHUP,  11},	/* D-Channel disconnected     */
	{"DCAL_I",         ISDN_STAT_ICALL, 3},	/* Incoming call dialup-line  */
	{"DSCA_I",         ISDN_STAT_ICALL, 3},	/* Incoming call 1TR6-SPV     */
	{"FCALL",          ISDN_STAT_ICALL, 4},	/* Leased line connection up  */
	{"CIF",            ISDN_STAT_CINF,  5},	/* Charge-info, 1TR6-type     */
	{"AOC",            ISDN_STAT_CINF,  6},	/* Charge-info, DSS1-type     */
	{"CAU",            ISDN_STAT_CAUSE, 7},	/* Cause code                 */
	{"TEI OK",         ISDN_STAT_RUN,   0},	/* Card connected to wallplug */
	{"NO D-CHAN",      ISDN_STAT_NODCH, 0},	/* No D-channel available     */
	{"E_L1: ACT FAIL", ISDN_STAT_BHUP,  8},	/* Layer-1 activation failed  */
	{"E_L2: DATA LIN", ISDN_STAT_BHUP,  8},	/* Layer-2 data link lost     */
	{"E_L1: ACTIVATION FAILED",
					   ISDN_STAT_BHUP,  8},	/* Layer-1 activation failed  */
	{NULL, 0, -1}
};
/* *INDENT-ON* */


/*
 * Check Statusqueue-Pointer from isdn-cards.
 * If there are new status-replies from the interface, check
 * them against B-Channel-connects/disconnects and set flags accordingly.
 * Wake-Up any processes, who are reading the status-device.
 * If there are B-Channels open, initiate a timer-callback to
 * icn_pollbchan().
 * This routine is called periodically via timer.
 */

static void
icn_parse_status(u_char * status, int channel, icn_card * card)
{
	icn_stat *s = icn_stat_table;
	int action = -1;
	unsigned long flags;
	isdn_ctrl cmd;

	while (s->statstr) {
		if (!strncmp(status, s->statstr, strlen(s->statstr))) {
			cmd.command = s->command;
			action = s->action;
			break;
		}
		s++;
	}
	if (action == -1)
		return;
	cmd.driver = card->myid;
	cmd.arg = channel;
	switch (action) {
	case 11:
			save_flags(flags);
			cli();
			icn_free_queue(card,channel);
			card->rcvidx[channel] = 0;

			if (card->flags & 
			    ((channel)?ICN_FLAGS_B2ACTIVE:ICN_FLAGS_B1ACTIVE)) {
				
				isdn_ctrl ncmd;
				
				card->flags &= ~((channel)?
						 ICN_FLAGS_B2ACTIVE:ICN_FLAGS_B1ACTIVE);
				
				memset(&ncmd, 0, sizeof(ncmd));
				
				ncmd.driver = card->myid;
				ncmd.arg = channel;
				ncmd.command = ISDN_STAT_BHUP;
				restore_flags(flags);
				card->interface.statcallb(&cmd);
			} else
				restore_flags(flags);
			
			break;
		case 1:
			icn_free_queue(card,channel);
			card->flags |= (channel) ?
			    ICN_FLAGS_B2ACTIVE : ICN_FLAGS_B1ACTIVE;
			break;
		case 2:
			card->flags &= ~((channel) ?
				ICN_FLAGS_B2ACTIVE : ICN_FLAGS_B1ACTIVE);
			icn_free_queue(card, channel);
			save_flags(flags);
			cli();
			card->rcvidx[channel] = 0;
			restore_flags(flags);
			break;
		case 3:
			{
				char *t = status + 6;
				char *s = strpbrk(t, ",");

				*s++ = '\0';
				strncpy(cmd.parm.setup.phone, t,
					sizeof(cmd.parm.setup.phone));
				s = strpbrk(t = s, ",");
				*s++ = '\0';
				if (!strlen(t))
					cmd.parm.setup.si1 = 0;
				else
					cmd.parm.setup.si1 =
					    simple_strtoul(t, NULL, 10);
				s = strpbrk(t = s, ",");
				*s++ = '\0';
				if (!strlen(t))
					cmd.parm.setup.si2 = 0;
				else
					cmd.parm.setup.si2 =
					    simple_strtoul(t, NULL, 10);
				strncpy(cmd.parm.setup.eazmsn, s,
					sizeof(cmd.parm.setup.eazmsn));
			}
			cmd.parm.setup.plan = 0;
			cmd.parm.setup.screen = 0;
			break;
		case 4:
			sprintf(cmd.parm.setup.phone, "LEASED%d", card->myid);
			sprintf(cmd.parm.setup.eazmsn, "%d", channel + 1);
			cmd.parm.setup.si1 = 7;
			cmd.parm.setup.si2 = 0;
			cmd.parm.setup.plan = 0;
			cmd.parm.setup.screen = 0;
			break;
		case 5:
			strncpy(cmd.parm.num, status + 3, sizeof(cmd.parm.num) - 1);
			break;
		case 6:
			sprintf(cmd.parm.num, "%d",
			     (int) simple_strtoul(status + 7, NULL, 16));
			break;
		case 7:
			status += 3;
			if (strlen(status) == 4)
				sprintf(cmd.parm.num, "%s%c%c",
				     status + 2, *status, *(status + 1));
			else
				strncpy(cmd.parm.num, status + 1, sizeof(cmd.parm.num) - 1);
			break;
		case 8:
			card->flags &= ~ICN_FLAGS_B1ACTIVE;
			icn_free_queue(card, 0);
			save_flags(flags);
			cli();
			card->rcvidx[0] = 0;
			restore_flags(flags);
			cmd.arg = 0;
			cmd.driver = card->myid;
			card->interface.statcallb(&cmd);
			cmd.command = ISDN_STAT_DHUP;
			cmd.arg = 0;
			cmd.driver = card->myid;
			card->interface.statcallb(&cmd);
			cmd.command = ISDN_STAT_BHUP;
			card->flags &= ~ICN_FLAGS_B2ACTIVE;
			icn_free_queue(card, 1);
			save_flags(flags);
			cli();
			card->rcvidx[1] = 0;
			restore_flags(flags);
			cmd.arg = 1;
			cmd.driver = card->myid;
			card->interface.statcallb(&cmd);
			cmd.command = ISDN_STAT_DHUP;
			cmd.arg = 1;
			cmd.driver = card->myid;
			break;
	}