xref: /openbmc/linux/drivers/isdn/mISDN/layer2.c (revision 1fa6ac37)
1 /*
2  *
3  * Author	Karsten Keil <kkeil@novell.com>
4  *
5  * Copyright 2008  by Karsten Keil <kkeil@novell.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  */
17 
18 #include <linux/mISDNif.h>
19 #include <linux/slab.h>
20 #include "core.h"
21 #include "fsm.h"
22 #include "layer2.h"
23 
24 static u_int *debug;
25 
26 static
27 struct Fsm l2fsm = {NULL, 0, 0, NULL, NULL};
28 
29 static char *strL2State[] =
30 {
31 	"ST_L2_1",
32 	"ST_L2_2",
33 	"ST_L2_3",
34 	"ST_L2_4",
35 	"ST_L2_5",
36 	"ST_L2_6",
37 	"ST_L2_7",
38 	"ST_L2_8",
39 };
40 
41 enum {
42 	EV_L2_UI,
43 	EV_L2_SABME,
44 	EV_L2_DISC,
45 	EV_L2_DM,
46 	EV_L2_UA,
47 	EV_L2_FRMR,
48 	EV_L2_SUPER,
49 	EV_L2_I,
50 	EV_L2_DL_DATA,
51 	EV_L2_ACK_PULL,
52 	EV_L2_DL_UNITDATA,
53 	EV_L2_DL_ESTABLISH_REQ,
54 	EV_L2_DL_RELEASE_REQ,
55 	EV_L2_MDL_ASSIGN,
56 	EV_L2_MDL_REMOVE,
57 	EV_L2_MDL_ERROR,
58 	EV_L1_DEACTIVATE,
59 	EV_L2_T200,
60 	EV_L2_T203,
61 	EV_L2_SET_OWN_BUSY,
62 	EV_L2_CLEAR_OWN_BUSY,
63 	EV_L2_FRAME_ERROR,
64 };
65 
66 #define L2_EVENT_COUNT (EV_L2_FRAME_ERROR+1)
67 
68 static char *strL2Event[] =
69 {
70 	"EV_L2_UI",
71 	"EV_L2_SABME",
72 	"EV_L2_DISC",
73 	"EV_L2_DM",
74 	"EV_L2_UA",
75 	"EV_L2_FRMR",
76 	"EV_L2_SUPER",
77 	"EV_L2_I",
78 	"EV_L2_DL_DATA",
79 	"EV_L2_ACK_PULL",
80 	"EV_L2_DL_UNITDATA",
81 	"EV_L2_DL_ESTABLISH_REQ",
82 	"EV_L2_DL_RELEASE_REQ",
83 	"EV_L2_MDL_ASSIGN",
84 	"EV_L2_MDL_REMOVE",
85 	"EV_L2_MDL_ERROR",
86 	"EV_L1_DEACTIVATE",
87 	"EV_L2_T200",
88 	"EV_L2_T203",
89 	"EV_L2_SET_OWN_BUSY",
90 	"EV_L2_CLEAR_OWN_BUSY",
91 	"EV_L2_FRAME_ERROR",
92 };
93 
94 static void
95 l2m_debug(struct FsmInst *fi, char *fmt, ...)
96 {
97 	struct layer2 *l2 = fi->userdata;
98 	va_list va;
99 
100 	if (!(*debug & DEBUG_L2_FSM))
101 		return;
102 	va_start(va, fmt);
103 	printk(KERN_DEBUG "l2 (sapi %d tei %d): ", l2->sapi, l2->tei);
104 	vprintk(fmt, va);
105 	printk("\n");
106 	va_end(va);
107 }
108 
109 inline u_int
110 l2headersize(struct layer2 *l2, int ui)
111 {
112 	return ((test_bit(FLG_MOD128, &l2->flag) && (!ui)) ? 2 : 1) +
113 		(test_bit(FLG_LAPD, &l2->flag) ? 2 : 1);
114 }
115 
116 inline u_int
117 l2addrsize(struct layer2 *l2)
118 {
119 	return test_bit(FLG_LAPD, &l2->flag) ? 2 : 1;
120 }
121 
122 static u_int
123 l2_newid(struct layer2 *l2)
124 {
125 	u_int	id;
126 
127 	id = l2->next_id++;
128 	if (id == 0x7fff)
129 		l2->next_id = 1;
130 	id <<= 16;
131 	id |= l2->tei << 8;
132 	id |= l2->sapi;
133 	return id;
134 }
135 
136 static void
137 l2up(struct layer2 *l2, u_int prim, struct sk_buff *skb)
138 {
139 	int	err;
140 
141 	if (!l2->up)
142 		return;
143 	mISDN_HEAD_PRIM(skb) = prim;
144 	mISDN_HEAD_ID(skb) = (l2->ch.nr << 16) | l2->ch.addr;
145 	err = l2->up->send(l2->up, skb);
146 	if (err) {
147 		printk(KERN_WARNING "%s: err=%d\n", __func__, err);
148 		dev_kfree_skb(skb);
149 	}
150 }
151 
152 static void
153 l2up_create(struct layer2 *l2, u_int prim, int len, void *arg)
154 {
155 	struct sk_buff	*skb;
156 	struct mISDNhead *hh;
157 	int		err;
158 
159 	if (!l2->up)
160 		return;
161 	skb = mI_alloc_skb(len, GFP_ATOMIC);
162 	if (!skb)
163 		return;
164 	hh = mISDN_HEAD_P(skb);
165 	hh->prim = prim;
166 	hh->id = (l2->ch.nr << 16) | l2->ch.addr;
167 	if (len)
168 		memcpy(skb_put(skb, len), arg, len);
169 	err = l2->up->send(l2->up, skb);
170 	if (err) {
171 		printk(KERN_WARNING "%s: err=%d\n", __func__, err);
172 		dev_kfree_skb(skb);
173 	}
174 }
175 
176 static int
177 l2down_skb(struct layer2 *l2, struct sk_buff *skb) {
178 	int ret;
179 
180 	ret = l2->ch.recv(l2->ch.peer, skb);
181 	if (ret && (*debug & DEBUG_L2_RECV))
182 		printk(KERN_DEBUG "l2down_skb: ret(%d)\n", ret);
183 	return ret;
184 }
185 
186 static int
187 l2down_raw(struct layer2 *l2, struct sk_buff *skb)
188 {
189 	struct mISDNhead *hh = mISDN_HEAD_P(skb);
190 
191 	if (hh->prim == PH_DATA_REQ) {
192 		if (test_and_set_bit(FLG_L1_NOTREADY, &l2->flag)) {
193 			skb_queue_tail(&l2->down_queue, skb);
194 			return 0;
195 		}
196 		l2->down_id = mISDN_HEAD_ID(skb);
197 	}
198 	return l2down_skb(l2, skb);
199 }
200 
201 static int
202 l2down(struct layer2 *l2, u_int prim, u_int id, struct sk_buff *skb)
203 {
204 	struct mISDNhead *hh = mISDN_HEAD_P(skb);
205 
206 	hh->prim = prim;
207 	hh->id = id;
208 	return l2down_raw(l2, skb);
209 }
210 
211 static int
212 l2down_create(struct layer2 *l2, u_int prim, u_int id, int len, void *arg)
213 {
214 	struct sk_buff	*skb;
215 	int		err;
216 	struct mISDNhead *hh;
217 
218 	skb = mI_alloc_skb(len, GFP_ATOMIC);
219 	if (!skb)
220 		return -ENOMEM;
221 	hh = mISDN_HEAD_P(skb);
222 	hh->prim = prim;
223 	hh->id = id;
224 	if (len)
225 		memcpy(skb_put(skb, len), arg, len);
226 	err = l2down_raw(l2, skb);
227 	if (err)
228 		dev_kfree_skb(skb);
229 	return err;
230 }
231 
232 static int
233 ph_data_confirm(struct layer2 *l2, struct mISDNhead *hh, struct sk_buff *skb) {
234 	struct sk_buff *nskb = skb;
235 	int ret = -EAGAIN;
236 
237 	if (test_bit(FLG_L1_NOTREADY, &l2->flag)) {
238 		if (hh->id == l2->down_id) {
239 			nskb = skb_dequeue(&l2->down_queue);
240 			if (nskb) {
241 				l2->down_id = mISDN_HEAD_ID(nskb);
242 				if (l2down_skb(l2, nskb)) {
243 					dev_kfree_skb(nskb);
244 					l2->down_id = MISDN_ID_NONE;
245 				}
246 			} else
247 				l2->down_id = MISDN_ID_NONE;
248 			if (ret) {
249 				dev_kfree_skb(skb);
250 				ret = 0;
251 			}
252 			if (l2->down_id == MISDN_ID_NONE) {
253 				test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
254 				mISDN_FsmEvent(&l2->l2m, EV_L2_ACK_PULL, NULL);
255 			}
256 		}
257 	}
258 	if (!test_and_set_bit(FLG_L1_NOTREADY, &l2->flag)) {
259 		nskb = skb_dequeue(&l2->down_queue);
260 		if (nskb) {
261 			l2->down_id = mISDN_HEAD_ID(nskb);
262 			if (l2down_skb(l2, nskb)) {
263 				dev_kfree_skb(nskb);
264 				l2->down_id = MISDN_ID_NONE;
265 				test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
266 			}
267 		} else
268 			test_and_clear_bit(FLG_L1_NOTREADY, &l2->flag);
269 	}
270 	return ret;
271 }
272 
273 static int
274 l2mgr(struct layer2 *l2, u_int prim, void *arg) {
275 	long c = (long)arg;
276 
277 	printk(KERN_WARNING
278 	    "l2mgr: addr:%x prim %x %c\n", l2->id, prim, (char)c);
279 	if (test_bit(FLG_LAPD, &l2->flag) &&
280 		!test_bit(FLG_FIXED_TEI, &l2->flag)) {
281 		switch (c) {
282 		case 'C':
283 		case 'D':
284 		case 'G':
285 		case 'H':
286 			l2_tei(l2, prim, (u_long)arg);
287 			break;
288 		}
289 	}
290 	return 0;
291 }
292 
293 static void
294 set_peer_busy(struct layer2 *l2) {
295 	test_and_set_bit(FLG_PEER_BUSY, &l2->flag);
296 	if (skb_queue_len(&l2->i_queue) || skb_queue_len(&l2->ui_queue))
297 		test_and_set_bit(FLG_L2BLOCK, &l2->flag);
298 }
299 
300 static void
301 clear_peer_busy(struct layer2 *l2) {
302 	if (test_and_clear_bit(FLG_PEER_BUSY, &l2->flag))
303 		test_and_clear_bit(FLG_L2BLOCK, &l2->flag);
304 }
305 
306 static void
307 InitWin(struct layer2 *l2)
308 {
309 	int i;
310 
311 	for (i = 0; i < MAX_WINDOW; i++)
312 		l2->windowar[i] = NULL;
313 }
314 
315 static int
316 freewin(struct layer2 *l2)
317 {
318 	int i, cnt = 0;
319 
320 	for (i = 0; i < MAX_WINDOW; i++) {
321 		if (l2->windowar[i]) {
322 			cnt++;
323 			dev_kfree_skb(l2->windowar[i]);
324 			l2->windowar[i] = NULL;
325 		}
326 	}
327 	return cnt;
328 }
329 
330 static void
331 ReleaseWin(struct layer2 *l2)
332 {
333 	int cnt = freewin(l2);
334 
335 	if (cnt)
336 		printk(KERN_WARNING
337 		    "isdnl2 freed %d skbuffs in release\n", cnt);
338 }
339 
340 inline unsigned int
341 cansend(struct layer2 *l2)
342 {
343 	unsigned int p1;
344 
345 	if (test_bit(FLG_MOD128, &l2->flag))
346 		p1 = (l2->vs - l2->va) % 128;
347 	else
348 		p1 = (l2->vs - l2->va) % 8;
349 	return (p1 < l2->window) && !test_bit(FLG_PEER_BUSY, &l2->flag);
350 }
351 
352 inline void
353 clear_exception(struct layer2 *l2)
354 {
355 	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
356 	test_and_clear_bit(FLG_REJEXC, &l2->flag);
357 	test_and_clear_bit(FLG_OWN_BUSY, &l2->flag);
358 	clear_peer_busy(l2);
359 }
360 
361 static int
362 sethdraddr(struct layer2 *l2, u_char *header, int rsp)
363 {
364 	u_char *ptr = header;
365 	int crbit = rsp;
366 
367 	if (test_bit(FLG_LAPD, &l2->flag)) {
368 		if (test_bit(FLG_LAPD_NET, &l2->flag))
369 			crbit = !crbit;
370 		*ptr++ = (l2->sapi << 2) | (crbit ? 2 : 0);
371 		*ptr++ = (l2->tei << 1) | 1;
372 		return 2;
373 	} else {
374 		if (test_bit(FLG_ORIG, &l2->flag))
375 			crbit = !crbit;
376 		if (crbit)
377 			*ptr++ = l2->addr.B;
378 		else
379 			*ptr++ = l2->addr.A;
380 		return 1;
381 	}
382 }
383 
384 static inline void
385 enqueue_super(struct layer2 *l2, struct sk_buff *skb)
386 {
387 	if (l2down(l2, PH_DATA_REQ, l2_newid(l2), skb))
388 		dev_kfree_skb(skb);
389 }
390 
391 static inline void
392 enqueue_ui(struct layer2 *l2, struct sk_buff *skb)
393 {
394 	if (l2->tm)
395 		l2_tei(l2, MDL_STATUS_UI_IND, 0);
396 	if (l2down(l2, PH_DATA_REQ, l2_newid(l2), skb))
397 		dev_kfree_skb(skb);
398 }
399 
400 inline int
401 IsUI(u_char *data)
402 {
403 	return (data[0] & 0xef) == UI;
404 }
405 
406 inline int
407 IsUA(u_char *data)
408 {
409 	return (data[0] & 0xef) == UA;
410 }
411 
412 inline int
413 IsDM(u_char *data)
414 {
415 	return (data[0] & 0xef) == DM;
416 }
417 
418 inline int
419 IsDISC(u_char *data)
420 {
421 	return (data[0] & 0xef) == DISC;
422 }
423 
424 inline int
425 IsRR(u_char *data, struct layer2 *l2)
426 {
427 	if (test_bit(FLG_MOD128, &l2->flag))
428 		return data[0] == RR;
429 	else
430 		return (data[0] & 0xf) == 1;
431 }
432 
433 inline int
434 IsSFrame(u_char *data, struct layer2 *l2)
435 {
436 	register u_char d = *data;
437 
438 	if (!test_bit(FLG_MOD128, &l2->flag))
439 		d &= 0xf;
440 	return ((d & 0xf3) == 1) && ((d & 0x0c) != 0x0c);
441 }
442 
443 inline int
444 IsSABME(u_char *data, struct layer2 *l2)
445 {
446 	u_char d = data[0] & ~0x10;
447 
448 	return test_bit(FLG_MOD128, &l2->flag) ? d == SABME : d == SABM;
449 }
450 
451 inline int
452 IsREJ(u_char *data, struct layer2 *l2)
453 {
454 	return test_bit(FLG_MOD128, &l2->flag) ?
455 		data[0] == REJ : (data[0] & 0xf) == REJ;
456 }
457 
458 inline int
459 IsFRMR(u_char *data)
460 {
461 	return (data[0] & 0xef) == FRMR;
462 }
463 
464 inline int
465 IsRNR(u_char *data, struct layer2 *l2)
466 {
467 	return test_bit(FLG_MOD128, &l2->flag) ?
468 	    data[0] == RNR : (data[0] & 0xf) == RNR;
469 }
470 
471 static int
472 iframe_error(struct layer2 *l2, struct sk_buff *skb)
473 {
474 	u_int	i;
475 	int	rsp = *skb->data & 0x2;
476 
477 	i = l2addrsize(l2) + (test_bit(FLG_MOD128, &l2->flag) ? 2 : 1);
478 	if (test_bit(FLG_ORIG, &l2->flag))
479 		rsp = !rsp;
480 	if (rsp)
481 		return 'L';
482 	if (skb->len < i)
483 		return 'N';
484 	if ((skb->len - i) > l2->maxlen)
485 		return 'O';
486 	return 0;
487 }
488 
489 static int
490 super_error(struct layer2 *l2, struct sk_buff *skb)
491 {
492 	if (skb->len != l2addrsize(l2) +
493 	    (test_bit(FLG_MOD128, &l2->flag) ? 2 : 1))
494 		return 'N';
495 	return 0;
496 }
497 
498 static int
499 unnum_error(struct layer2 *l2, struct sk_buff *skb, int wantrsp)
500 {
501 	int rsp = (*skb->data & 0x2) >> 1;
502 	if (test_bit(FLG_ORIG, &l2->flag))
503 		rsp = !rsp;
504 	if (rsp != wantrsp)
505 		return 'L';
506 	if (skb->len != l2addrsize(l2) + 1)
507 		return 'N';
508 	return 0;
509 }
510 
511 static int
512 UI_error(struct layer2 *l2, struct sk_buff *skb)
513 {
514 	int rsp = *skb->data & 0x2;
515 	if (test_bit(FLG_ORIG, &l2->flag))
516 		rsp = !rsp;
517 	if (rsp)
518 		return 'L';
519 	if (skb->len > l2->maxlen + l2addrsize(l2) + 1)
520 		return 'O';
521 	return 0;
522 }
523 
524 static int
525 FRMR_error(struct layer2 *l2, struct sk_buff *skb)
526 {
527 	u_int	headers = l2addrsize(l2) + 1;
528 	u_char	*datap = skb->data + headers;
529 	int	rsp = *skb->data & 0x2;
530 
531 	if (test_bit(FLG_ORIG, &l2->flag))
532 		rsp = !rsp;
533 	if (!rsp)
534 		return 'L';
535 	if (test_bit(FLG_MOD128, &l2->flag)) {
536 		if (skb->len < headers + 5)
537 			return 'N';
538 		else if (*debug & DEBUG_L2)
539 			l2m_debug(&l2->l2m,
540 			    "FRMR information %2x %2x %2x %2x %2x",
541 			    datap[0], datap[1], datap[2], datap[3], datap[4]);
542 	} else {
543 		if (skb->len < headers + 3)
544 			return 'N';
545 		else if (*debug & DEBUG_L2)
546 			l2m_debug(&l2->l2m,
547 			    "FRMR information %2x %2x %2x",
548 			    datap[0], datap[1], datap[2]);
549 	}
550 	return 0;
551 }
552 
553 static unsigned int
554 legalnr(struct layer2 *l2, unsigned int nr)
555 {
556 	if (test_bit(FLG_MOD128, &l2->flag))
557 		return ((nr - l2->va) % 128) <= ((l2->vs - l2->va) % 128);
558 	else
559 		return ((nr - l2->va) % 8) <= ((l2->vs - l2->va) % 8);
560 }
561 
562 static void
563 setva(struct layer2 *l2, unsigned int nr)
564 {
565 	struct sk_buff	*skb;
566 
567 	while (l2->va != nr) {
568 		l2->va++;
569 		if (test_bit(FLG_MOD128, &l2->flag))
570 			l2->va %= 128;
571 		else
572 			l2->va %= 8;
573 		if (l2->windowar[l2->sow]) {
574 			skb_trim(l2->windowar[l2->sow], 0);
575 			skb_queue_tail(&l2->tmp_queue, l2->windowar[l2->sow]);
576 			l2->windowar[l2->sow] = NULL;
577 		}
578 		l2->sow = (l2->sow + 1) % l2->window;
579 	}
580 	skb = skb_dequeue(&l2->tmp_queue);
581 	while (skb) {
582 		dev_kfree_skb(skb);
583 		skb = skb_dequeue(&l2->tmp_queue);
584 	}
585 }
586 
587 static void
588 send_uframe(struct layer2 *l2, struct sk_buff *skb, u_char cmd, u_char cr)
589 {
590 	u_char tmp[MAX_L2HEADER_LEN];
591 	int i;
592 
593 	i = sethdraddr(l2, tmp, cr);
594 	tmp[i++] = cmd;
595 	if (skb)
596 		skb_trim(skb, 0);
597 	else {
598 		skb = mI_alloc_skb(i, GFP_ATOMIC);
599 		if (!skb) {
600 			printk(KERN_WARNING "%s: can't alloc skbuff\n",
601 				__func__);
602 			return;
603 		}
604 	}
605 	memcpy(skb_put(skb, i), tmp, i);
606 	enqueue_super(l2, skb);
607 }
608 
609 
610 inline u_char
611 get_PollFlag(struct layer2 *l2, struct sk_buff *skb)
612 {
613 	return skb->data[l2addrsize(l2)] & 0x10;
614 }
615 
616 inline u_char
617 get_PollFlagFree(struct layer2 *l2, struct sk_buff *skb)
618 {
619 	u_char PF;
620 
621 	PF = get_PollFlag(l2, skb);
622 	dev_kfree_skb(skb);
623 	return PF;
624 }
625 
626 inline void
627 start_t200(struct layer2 *l2, int i)
628 {
629 	mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, i);
630 	test_and_set_bit(FLG_T200_RUN, &l2->flag);
631 }
632 
633 inline void
634 restart_t200(struct layer2 *l2, int i)
635 {
636 	mISDN_FsmRestartTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, i);
637 	test_and_set_bit(FLG_T200_RUN, &l2->flag);
638 }
639 
640 inline void
641 stop_t200(struct layer2 *l2, int i)
642 {
643 	if (test_and_clear_bit(FLG_T200_RUN, &l2->flag))
644 		mISDN_FsmDelTimer(&l2->t200, i);
645 }
646 
647 inline void
648 st5_dl_release_l2l3(struct layer2 *l2)
649 {
650 	int pr;
651 
652 	if (test_and_clear_bit(FLG_PEND_REL, &l2->flag))
653 		pr = DL_RELEASE_CNF;
654 	else
655 		pr = DL_RELEASE_IND;
656 	l2up_create(l2, pr, 0, NULL);
657 }
658 
659 inline void
660 lapb_dl_release_l2l3(struct layer2 *l2, int f)
661 {
662 	if (test_bit(FLG_LAPB, &l2->flag))
663 		l2down_create(l2, PH_DEACTIVATE_REQ, l2_newid(l2), 0, NULL);
664 	l2up_create(l2, f, 0, NULL);
665 }
666 
667 static void
668 establishlink(struct FsmInst *fi)
669 {
670 	struct layer2 *l2 = fi->userdata;
671 	u_char cmd;
672 
673 	clear_exception(l2);
674 	l2->rc = 0;
675 	cmd = (test_bit(FLG_MOD128, &l2->flag) ? SABME : SABM) | 0x10;
676 	send_uframe(l2, NULL, cmd, CMD);
677 	mISDN_FsmDelTimer(&l2->t203, 1);
678 	restart_t200(l2, 1);
679 	test_and_clear_bit(FLG_PEND_REL, &l2->flag);
680 	freewin(l2);
681 	mISDN_FsmChangeState(fi, ST_L2_5);
682 }
683 
684 static void
685 l2_mdl_error_ua(struct FsmInst *fi, int event, void *arg)
686 {
687 	struct sk_buff *skb = arg;
688 	struct layer2 *l2 = fi->userdata;
689 
690 	if (get_PollFlagFree(l2, skb))
691 		l2mgr(l2, MDL_ERROR_IND, (void *) 'C');
692 	else
693 		l2mgr(l2, MDL_ERROR_IND, (void *) 'D');
694 
695 }
696 
697 static void
698 l2_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
699 {
700 	struct sk_buff *skb = arg;
701 	struct layer2 *l2 = fi->userdata;
702 
703 	if (get_PollFlagFree(l2, skb))
704 		l2mgr(l2, MDL_ERROR_IND, (void *) 'B');
705 	else {
706 		l2mgr(l2, MDL_ERROR_IND, (void *) 'E');
707 		establishlink(fi);
708 		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
709 	}
710 }
711 
712 static void
713 l2_st8_mdl_error_dm(struct FsmInst *fi, int event, void *arg)
714 {
715 	struct sk_buff *skb = arg;
716 	struct layer2 *l2 = fi->userdata;
717 
718 	if (get_PollFlagFree(l2, skb))
719 		l2mgr(l2, MDL_ERROR_IND, (void *) 'B');
720 	else
721 		l2mgr(l2, MDL_ERROR_IND, (void *) 'E');
722 	establishlink(fi);
723 	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
724 }
725 
726 static void
727 l2_go_st3(struct FsmInst *fi, int event, void *arg)
728 {
729 	dev_kfree_skb((struct sk_buff *)arg);
730 	mISDN_FsmChangeState(fi, ST_L2_3);
731 }
732 
733 static void
734 l2_mdl_assign(struct FsmInst *fi, int event, void *arg)
735 {
736 	struct layer2	*l2 = fi->userdata;
737 
738 	mISDN_FsmChangeState(fi, ST_L2_3);
739 	dev_kfree_skb((struct sk_buff *)arg);
740 	l2_tei(l2, MDL_ASSIGN_IND, 0);
741 }
742 
743 static void
744 l2_queue_ui_assign(struct FsmInst *fi, int event, void *arg)
745 {
746 	struct layer2 *l2 = fi->userdata;
747 	struct sk_buff *skb = arg;
748 
749 	skb_queue_tail(&l2->ui_queue, skb);
750 	mISDN_FsmChangeState(fi, ST_L2_2);
751 	l2_tei(l2, MDL_ASSIGN_IND, 0);
752 }
753 
754 static void
755 l2_queue_ui(struct FsmInst *fi, int event, void *arg)
756 {
757 	struct layer2 *l2 = fi->userdata;
758 	struct sk_buff *skb = arg;
759 
760 	skb_queue_tail(&l2->ui_queue, skb);
761 }
762 
763 static void
764 tx_ui(struct layer2 *l2)
765 {
766 	struct sk_buff *skb;
767 	u_char header[MAX_L2HEADER_LEN];
768 	int i;
769 
770 	i = sethdraddr(l2, header, CMD);
771 	if (test_bit(FLG_LAPD_NET, &l2->flag))
772 		header[1] = 0xff; /* tei 127 */
773 	header[i++] = UI;
774 	while ((skb = skb_dequeue(&l2->ui_queue))) {
775 		memcpy(skb_push(skb, i), header, i);
776 		enqueue_ui(l2, skb);
777 	}
778 }
779 
780 static void
781 l2_send_ui(struct FsmInst *fi, int event, void *arg)
782 {
783 	struct layer2 *l2 = fi->userdata;
784 	struct sk_buff *skb = arg;
785 
786 	skb_queue_tail(&l2->ui_queue, skb);
787 	tx_ui(l2);
788 }
789 
790 static void
791 l2_got_ui(struct FsmInst *fi, int event, void *arg)
792 {
793 	struct layer2 *l2 = fi->userdata;
794 	struct sk_buff *skb = arg;
795 
796 	skb_pull(skb, l2headersize(l2, 1));
797 /*
798  *		in states 1-3 for broadcast
799  */
800 
801 	if (l2->tm)
802 		l2_tei(l2, MDL_STATUS_UI_IND, 0);
803 	l2up(l2, DL_UNITDATA_IND, skb);
804 }
805 
806 static void
807 l2_establish(struct FsmInst *fi, int event, void *arg)
808 {
809 	struct sk_buff *skb = arg;
810 	struct layer2 *l2 = fi->userdata;
811 
812 	establishlink(fi);
813 	test_and_set_bit(FLG_L3_INIT, &l2->flag);
814 	dev_kfree_skb(skb);
815 }
816 
817 static void
818 l2_discard_i_setl3(struct FsmInst *fi, int event, void *arg)
819 {
820 	struct sk_buff *skb = arg;
821 	struct layer2 *l2 = fi->userdata;
822 
823 	skb_queue_purge(&l2->i_queue);
824 	test_and_set_bit(FLG_L3_INIT, &l2->flag);
825 	test_and_clear_bit(FLG_PEND_REL, &l2->flag);
826 	dev_kfree_skb(skb);
827 }
828 
829 static void
830 l2_l3_reestablish(struct FsmInst *fi, int event, void *arg)
831 {
832 	struct sk_buff *skb = arg;
833 	struct layer2 *l2 = fi->userdata;
834 
835 	skb_queue_purge(&l2->i_queue);
836 	establishlink(fi);
837 	test_and_set_bit(FLG_L3_INIT, &l2->flag);
838 	dev_kfree_skb(skb);
839 }
840 
841 static void
842 l2_release(struct FsmInst *fi, int event, void *arg)
843 {
844 	struct layer2 *l2 = fi->userdata;
845 	struct sk_buff *skb = arg;
846 
847 	skb_trim(skb, 0);
848 	l2up(l2, DL_RELEASE_CNF, skb);
849 }
850 
851 static void
852 l2_pend_rel(struct FsmInst *fi, int event, void *arg)
853 {
854 	struct sk_buff *skb = arg;
855 	struct layer2 *l2 = fi->userdata;
856 
857 	test_and_set_bit(FLG_PEND_REL, &l2->flag);
858 	dev_kfree_skb(skb);
859 }
860 
861 static void
862 l2_disconnect(struct FsmInst *fi, int event, void *arg)
863 {
864 	struct layer2 *l2 = fi->userdata;
865 	struct sk_buff *skb = arg;
866 
867 	skb_queue_purge(&l2->i_queue);
868 	freewin(l2);
869 	mISDN_FsmChangeState(fi, ST_L2_6);
870 	l2->rc = 0;
871 	send_uframe(l2, NULL, DISC | 0x10, CMD);
872 	mISDN_FsmDelTimer(&l2->t203, 1);
873 	restart_t200(l2, 2);
874 	if (skb)
875 		dev_kfree_skb(skb);
876 }
877 
878 static void
879 l2_start_multi(struct FsmInst *fi, int event, void *arg)
880 {
881 	struct layer2	*l2 = fi->userdata;
882 	struct sk_buff	*skb = arg;
883 
884 	l2->vs = 0;
885 	l2->va = 0;
886 	l2->vr = 0;
887 	l2->sow = 0;
888 	clear_exception(l2);
889 	send_uframe(l2, NULL, UA | get_PollFlag(l2, skb), RSP);
890 	mISDN_FsmChangeState(fi, ST_L2_7);
891 	mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 3);
892 	skb_trim(skb, 0);
893 	l2up(l2, DL_ESTABLISH_IND, skb);
894 	if (l2->tm)
895 		l2_tei(l2, MDL_STATUS_UP_IND, 0);
896 }
897 
898 static void
899 l2_send_UA(struct FsmInst *fi, int event, void *arg)
900 {
901 	struct layer2 *l2 = fi->userdata;
902 	struct sk_buff *skb = arg;
903 
904 	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
905 }
906 
907 static void
908 l2_send_DM(struct FsmInst *fi, int event, void *arg)
909 {
910 	struct layer2 *l2 = fi->userdata;
911 	struct sk_buff *skb = arg;
912 
913 	send_uframe(l2, skb, DM | get_PollFlag(l2, skb), RSP);
914 }
915 
916 static void
917 l2_restart_multi(struct FsmInst *fi, int event, void *arg)
918 {
919 	struct layer2	*l2 = fi->userdata;
920 	struct sk_buff	*skb = arg;
921 	int		est = 0;
922 
923 	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
924 
925 	l2mgr(l2, MDL_ERROR_IND, (void *) 'F');
926 
927 	if (l2->vs != l2->va) {
928 		skb_queue_purge(&l2->i_queue);
929 		est = 1;
930 	}
931 
932 	clear_exception(l2);
933 	l2->vs = 0;
934 	l2->va = 0;
935 	l2->vr = 0;
936 	l2->sow = 0;
937 	mISDN_FsmChangeState(fi, ST_L2_7);
938 	stop_t200(l2, 3);
939 	mISDN_FsmRestartTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 3);
940 
941 	if (est)
942 		l2up_create(l2, DL_ESTABLISH_IND, 0, NULL);
943 /*		mISDN_queue_data(&l2->inst, l2->inst.id | MSG_BROADCAST,
944  *		    MGR_SHORTSTATUS | INDICATION, SSTATUS_L2_ESTABLISHED,
945  *		    0, NULL, 0);
946  */
947 	if (skb_queue_len(&l2->i_queue) && cansend(l2))
948 		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
949 }
950 
951 static void
952 l2_stop_multi(struct FsmInst *fi, int event, void *arg)
953 {
954 	struct layer2	*l2 = fi->userdata;
955 	struct sk_buff	*skb = arg;
956 
957 	mISDN_FsmChangeState(fi, ST_L2_4);
958 	mISDN_FsmDelTimer(&l2->t203, 3);
959 	stop_t200(l2, 4);
960 
961 	send_uframe(l2, skb, UA | get_PollFlag(l2, skb), RSP);
962 	skb_queue_purge(&l2->i_queue);
963 	freewin(l2);
964 	lapb_dl_release_l2l3(l2, DL_RELEASE_IND);
965 	if (l2->tm)
966 		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
967 }
968 
969 static void
970 l2_connected(struct FsmInst *fi, int event, void *arg)
971 {
972 	struct layer2	*l2 = fi->userdata;
973 	struct sk_buff	*skb = arg;
974 	int pr = -1;
975 
976 	if (!get_PollFlag(l2, skb)) {
977 		l2_mdl_error_ua(fi, event, arg);
978 		return;
979 	}
980 	dev_kfree_skb(skb);
981 	if (test_and_clear_bit(FLG_PEND_REL, &l2->flag))
982 		l2_disconnect(fi, event, NULL);
983 	if (test_and_clear_bit(FLG_L3_INIT, &l2->flag)) {
984 		pr = DL_ESTABLISH_CNF;
985 	} else if (l2->vs != l2->va) {
986 		skb_queue_purge(&l2->i_queue);
987 		pr = DL_ESTABLISH_IND;
988 	}
989 	stop_t200(l2, 5);
990 	l2->vr = 0;
991 	l2->vs = 0;
992 	l2->va = 0;
993 	l2->sow = 0;
994 	mISDN_FsmChangeState(fi, ST_L2_7);
995 	mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 4);
996 	if (pr != -1)
997 		l2up_create(l2, pr, 0, NULL);
998 
999 	if (skb_queue_len(&l2->i_queue) && cansend(l2))
1000 		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
1001 
1002 	if (l2->tm)
1003 		l2_tei(l2, MDL_STATUS_UP_IND, 0);
1004 }
1005 
1006 static void
1007 l2_released(struct FsmInst *fi, int event, void *arg)
1008 {
1009 	struct layer2 *l2 = fi->userdata;
1010 	struct sk_buff *skb = arg;
1011 
1012 	if (!get_PollFlag(l2, skb)) {
1013 		l2_mdl_error_ua(fi, event, arg);
1014 		return;
1015 	}
1016 	dev_kfree_skb(skb);
1017 	stop_t200(l2, 6);
1018 	lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
1019 	mISDN_FsmChangeState(fi, ST_L2_4);
1020 	if (l2->tm)
1021 		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1022 }
1023 
1024 static void
1025 l2_reestablish(struct FsmInst *fi, int event, void *arg)
1026 {
1027 	struct layer2 *l2 = fi->userdata;
1028 	struct sk_buff *skb = arg;
1029 
1030 	if (!get_PollFlagFree(l2, skb)) {
1031 		establishlink(fi);
1032 		test_and_set_bit(FLG_L3_INIT, &l2->flag);
1033 	}
1034 }
1035 
1036 static void
1037 l2_st5_dm_release(struct FsmInst *fi, int event, void *arg)
1038 {
1039 	struct layer2 *l2 = fi->userdata;
1040 	struct sk_buff *skb = arg;
1041 
1042 	if (get_PollFlagFree(l2, skb)) {
1043 		stop_t200(l2, 7);
1044 		if (!test_bit(FLG_L3_INIT, &l2->flag))
1045 			skb_queue_purge(&l2->i_queue);
1046 		if (test_bit(FLG_LAPB, &l2->flag))
1047 			l2down_create(l2, PH_DEACTIVATE_REQ,
1048 				l2_newid(l2), 0, NULL);
1049 		st5_dl_release_l2l3(l2);
1050 		mISDN_FsmChangeState(fi, ST_L2_4);
1051 		if (l2->tm)
1052 			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1053 	}
1054 }
1055 
1056 static void
1057 l2_st6_dm_release(struct FsmInst *fi, int event, void *arg)
1058 {
1059 	struct layer2 *l2 = fi->userdata;
1060 	struct sk_buff *skb = arg;
1061 
1062 	if (get_PollFlagFree(l2, skb)) {
1063 		stop_t200(l2, 8);
1064 		lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
1065 		mISDN_FsmChangeState(fi, ST_L2_4);
1066 		if (l2->tm)
1067 			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1068 	}
1069 }
1070 
1071 static void
1072 enquiry_cr(struct layer2 *l2, u_char typ, u_char cr, u_char pf)
1073 {
1074 	struct sk_buff *skb;
1075 	u_char tmp[MAX_L2HEADER_LEN];
1076 	int i;
1077 
1078 	i = sethdraddr(l2, tmp, cr);
1079 	if (test_bit(FLG_MOD128, &l2->flag)) {
1080 		tmp[i++] = typ;
1081 		tmp[i++] = (l2->vr << 1) | (pf ? 1 : 0);
1082 	} else
1083 		tmp[i++] = (l2->vr << 5) | typ | (pf ? 0x10 : 0);
1084 	skb = mI_alloc_skb(i, GFP_ATOMIC);
1085 	if (!skb) {
1086 		printk(KERN_WARNING
1087 		    "isdnl2 can't alloc sbbuff for enquiry_cr\n");
1088 		return;
1089 	}
1090 	memcpy(skb_put(skb, i), tmp, i);
1091 	enqueue_super(l2, skb);
1092 }
1093 
1094 inline void
1095 enquiry_response(struct layer2 *l2)
1096 {
1097 	if (test_bit(FLG_OWN_BUSY, &l2->flag))
1098 		enquiry_cr(l2, RNR, RSP, 1);
1099 	else
1100 		enquiry_cr(l2, RR, RSP, 1);
1101 	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1102 }
1103 
1104 inline void
1105 transmit_enquiry(struct layer2 *l2)
1106 {
1107 	if (test_bit(FLG_OWN_BUSY, &l2->flag))
1108 		enquiry_cr(l2, RNR, CMD, 1);
1109 	else
1110 		enquiry_cr(l2, RR, CMD, 1);
1111 	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1112 	start_t200(l2, 9);
1113 }
1114 
1115 
1116 static void
1117 nrerrorrecovery(struct FsmInst *fi)
1118 {
1119 	struct layer2 *l2 = fi->userdata;
1120 
1121 	l2mgr(l2, MDL_ERROR_IND, (void *) 'J');
1122 	establishlink(fi);
1123 	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
1124 }
1125 
1126 static void
1127 invoke_retransmission(struct layer2 *l2, unsigned int nr)
1128 {
1129 	u_int	p1;
1130 
1131 	if (l2->vs != nr) {
1132 		while (l2->vs != nr) {
1133 			(l2->vs)--;
1134 			if (test_bit(FLG_MOD128, &l2->flag)) {
1135 				l2->vs %= 128;
1136 				p1 = (l2->vs - l2->va) % 128;
1137 			} else {
1138 				l2->vs %= 8;
1139 				p1 = (l2->vs - l2->va) % 8;
1140 			}
1141 			p1 = (p1 + l2->sow) % l2->window;
1142 			if (l2->windowar[p1])
1143 				skb_queue_head(&l2->i_queue, l2->windowar[p1]);
1144 			else
1145 				printk(KERN_WARNING
1146 				    "%s: windowar[%d] is NULL\n",
1147 				    __func__, p1);
1148 			l2->windowar[p1] = NULL;
1149 		}
1150 		mISDN_FsmEvent(&l2->l2m, EV_L2_ACK_PULL, NULL);
1151 	}
1152 }
1153 
1154 static void
1155 l2_st7_got_super(struct FsmInst *fi, int event, void *arg)
1156 {
1157 	struct layer2 *l2 = fi->userdata;
1158 	struct sk_buff *skb = arg;
1159 	int PollFlag, rsp, typ = RR;
1160 	unsigned int nr;
1161 
1162 	rsp = *skb->data & 0x2;
1163 	if (test_bit(FLG_ORIG, &l2->flag))
1164 		rsp = !rsp;
1165 
1166 	skb_pull(skb, l2addrsize(l2));
1167 	if (IsRNR(skb->data, l2)) {
1168 		set_peer_busy(l2);
1169 		typ = RNR;
1170 	} else
1171 		clear_peer_busy(l2);
1172 	if (IsREJ(skb->data, l2))
1173 		typ = REJ;
1174 
1175 	if (test_bit(FLG_MOD128, &l2->flag)) {
1176 		PollFlag = (skb->data[1] & 0x1) == 0x1;
1177 		nr = skb->data[1] >> 1;
1178 	} else {
1179 		PollFlag = (skb->data[0] & 0x10);
1180 		nr = (skb->data[0] >> 5) & 0x7;
1181 	}
1182 	dev_kfree_skb(skb);
1183 
1184 	if (PollFlag) {
1185 		if (rsp)
1186 			l2mgr(l2, MDL_ERROR_IND, (void *) 'A');
1187 		else
1188 			enquiry_response(l2);
1189 	}
1190 	if (legalnr(l2, nr)) {
1191 		if (typ == REJ) {
1192 			setva(l2, nr);
1193 			invoke_retransmission(l2, nr);
1194 			stop_t200(l2, 10);
1195 			if (mISDN_FsmAddTimer(&l2->t203, l2->T203,
1196 					EV_L2_T203, NULL, 6))
1197 				l2m_debug(&l2->l2m, "Restart T203 ST7 REJ");
1198 		} else if ((nr == l2->vs) && (typ == RR)) {
1199 			setva(l2, nr);
1200 			stop_t200(l2, 11);
1201 			mISDN_FsmRestartTimer(&l2->t203, l2->T203,
1202 					EV_L2_T203, NULL, 7);
1203 		} else if ((l2->va != nr) || (typ == RNR)) {
1204 			setva(l2, nr);
1205 			if (typ != RR)
1206 				mISDN_FsmDelTimer(&l2->t203, 9);
1207 			restart_t200(l2, 12);
1208 		}
1209 		if (skb_queue_len(&l2->i_queue) && (typ == RR))
1210 			mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
1211 	} else
1212 		nrerrorrecovery(fi);
1213 }
1214 
1215 static void
1216 l2_feed_i_if_reest(struct FsmInst *fi, int event, void *arg)
1217 {
1218 	struct layer2 *l2 = fi->userdata;
1219 	struct sk_buff *skb = arg;
1220 
1221 	if (!test_bit(FLG_L3_INIT, &l2->flag))
1222 		skb_queue_tail(&l2->i_queue, skb);
1223 	else
1224 		dev_kfree_skb(skb);
1225 }
1226 
1227 static void
1228 l2_feed_i_pull(struct FsmInst *fi, int event, void *arg)
1229 {
1230 	struct layer2 *l2 = fi->userdata;
1231 	struct sk_buff *skb = arg;
1232 
1233 	skb_queue_tail(&l2->i_queue, skb);
1234 	mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
1235 }
1236 
1237 static void
1238 l2_feed_iqueue(struct FsmInst *fi, int event, void *arg)
1239 {
1240 	struct layer2 *l2 = fi->userdata;
1241 	struct sk_buff *skb = arg;
1242 
1243 	skb_queue_tail(&l2->i_queue, skb);
1244 }
1245 
1246 static void
1247 l2_got_iframe(struct FsmInst *fi, int event, void *arg)
1248 {
1249 	struct layer2	*l2 = fi->userdata;
1250 	struct sk_buff	*skb = arg;
1251 	int		PollFlag, i;
1252 	u_int		ns, nr;
1253 
1254 	i = l2addrsize(l2);
1255 	if (test_bit(FLG_MOD128, &l2->flag)) {
1256 		PollFlag = ((skb->data[i + 1] & 0x1) == 0x1);
1257 		ns = skb->data[i] >> 1;
1258 		nr = (skb->data[i + 1] >> 1) & 0x7f;
1259 	} else {
1260 		PollFlag = (skb->data[i] & 0x10);
1261 		ns = (skb->data[i] >> 1) & 0x7;
1262 		nr = (skb->data[i] >> 5) & 0x7;
1263 	}
1264 	if (test_bit(FLG_OWN_BUSY, &l2->flag)) {
1265 		dev_kfree_skb(skb);
1266 		if (PollFlag)
1267 			enquiry_response(l2);
1268 	} else {
1269 		if (l2->vr == ns) {
1270 			l2->vr++;
1271 			if (test_bit(FLG_MOD128, &l2->flag))
1272 				l2->vr %= 128;
1273 			else
1274 				l2->vr %= 8;
1275 			test_and_clear_bit(FLG_REJEXC, &l2->flag);
1276 			if (PollFlag)
1277 				enquiry_response(l2);
1278 			else
1279 				test_and_set_bit(FLG_ACK_PEND, &l2->flag);
1280 			skb_pull(skb, l2headersize(l2, 0));
1281 			l2up(l2, DL_DATA_IND, skb);
1282 		} else {
1283 			/* n(s)!=v(r) */
1284 			dev_kfree_skb(skb);
1285 			if (test_and_set_bit(FLG_REJEXC, &l2->flag)) {
1286 				if (PollFlag)
1287 					enquiry_response(l2);
1288 			} else {
1289 				enquiry_cr(l2, REJ, RSP, PollFlag);
1290 				test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1291 			}
1292 		}
1293 	}
1294 	if (legalnr(l2, nr)) {
1295 		if (!test_bit(FLG_PEER_BUSY, &l2->flag) &&
1296 		    (fi->state == ST_L2_7)) {
1297 			if (nr == l2->vs) {
1298 				stop_t200(l2, 13);
1299 				mISDN_FsmRestartTimer(&l2->t203, l2->T203,
1300 						EV_L2_T203, NULL, 7);
1301 			} else if (nr != l2->va)
1302 				restart_t200(l2, 14);
1303 		}
1304 		setva(l2, nr);
1305 	} else {
1306 		nrerrorrecovery(fi);
1307 		return;
1308 	}
1309 	if (skb_queue_len(&l2->i_queue) && (fi->state == ST_L2_7))
1310 		mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
1311 	if (test_and_clear_bit(FLG_ACK_PEND, &l2->flag))
1312 		enquiry_cr(l2, RR, RSP, 0);
1313 }
1314 
1315 static void
1316 l2_got_tei(struct FsmInst *fi, int event, void *arg)
1317 {
1318 	struct layer2	*l2 = fi->userdata;
1319 	u_int		info;
1320 
1321 	l2->tei = (signed char)(long)arg;
1322 	set_channel_address(&l2->ch, l2->sapi, l2->tei);
1323 	info = DL_INFO_L2_CONNECT;
1324 	l2up_create(l2, DL_INFORMATION_IND, sizeof(info), &info);
1325 	if (fi->state == ST_L2_3) {
1326 		establishlink(fi);
1327 		test_and_set_bit(FLG_L3_INIT, &l2->flag);
1328 	} else
1329 		mISDN_FsmChangeState(fi, ST_L2_4);
1330 	if (skb_queue_len(&l2->ui_queue))
1331 		tx_ui(l2);
1332 }
1333 
1334 static void
1335 l2_st5_tout_200(struct FsmInst *fi, int event, void *arg)
1336 {
1337 	struct layer2 *l2 = fi->userdata;
1338 
1339 	if (test_bit(FLG_LAPD, &l2->flag) &&
1340 		test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
1341 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
1342 	} else if (l2->rc == l2->N200) {
1343 		mISDN_FsmChangeState(fi, ST_L2_4);
1344 		test_and_clear_bit(FLG_T200_RUN, &l2->flag);
1345 		skb_queue_purge(&l2->i_queue);
1346 		l2mgr(l2, MDL_ERROR_IND, (void *) 'G');
1347 		if (test_bit(FLG_LAPB, &l2->flag))
1348 			l2down_create(l2, PH_DEACTIVATE_REQ,
1349 				l2_newid(l2), 0, NULL);
1350 		st5_dl_release_l2l3(l2);
1351 		if (l2->tm)
1352 			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1353 	} else {
1354 		l2->rc++;
1355 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
1356 		send_uframe(l2, NULL, (test_bit(FLG_MOD128, &l2->flag) ?
1357 			SABME : SABM) | 0x10, CMD);
1358 	}
1359 }
1360 
1361 static void
1362 l2_st6_tout_200(struct FsmInst *fi, int event, void *arg)
1363 {
1364 	struct layer2 *l2 = fi->userdata;
1365 
1366 	if (test_bit(FLG_LAPD, &l2->flag) &&
1367 		test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
1368 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
1369 	} else if (l2->rc == l2->N200) {
1370 		mISDN_FsmChangeState(fi, ST_L2_4);
1371 		test_and_clear_bit(FLG_T200_RUN, &l2->flag);
1372 		l2mgr(l2, MDL_ERROR_IND, (void *) 'H');
1373 		lapb_dl_release_l2l3(l2, DL_RELEASE_CNF);
1374 		if (l2->tm)
1375 			l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1376 	} else {
1377 		l2->rc++;
1378 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200,
1379 			    NULL, 9);
1380 		send_uframe(l2, NULL, DISC | 0x10, CMD);
1381 	}
1382 }
1383 
1384 static void
1385 l2_st7_tout_200(struct FsmInst *fi, int event, void *arg)
1386 {
1387 	struct layer2 *l2 = fi->userdata;
1388 
1389 	if (test_bit(FLG_LAPD, &l2->flag) &&
1390 		test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
1391 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
1392 		return;
1393 	}
1394 	test_and_clear_bit(FLG_T200_RUN, &l2->flag);
1395 	l2->rc = 0;
1396 	mISDN_FsmChangeState(fi, ST_L2_8);
1397 	transmit_enquiry(l2);
1398 	l2->rc++;
1399 }
1400 
1401 static void
1402 l2_st8_tout_200(struct FsmInst *fi, int event, void *arg)
1403 {
1404 	struct layer2 *l2 = fi->userdata;
1405 
1406 	if (test_bit(FLG_LAPD, &l2->flag) &&
1407 		test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
1408 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 9);
1409 		return;
1410 	}
1411 	test_and_clear_bit(FLG_T200_RUN, &l2->flag);
1412 	if (l2->rc == l2->N200) {
1413 		l2mgr(l2, MDL_ERROR_IND, (void *) 'I');
1414 		establishlink(fi);
1415 		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
1416 	} else {
1417 		transmit_enquiry(l2);
1418 		l2->rc++;
1419 	}
1420 }
1421 
1422 static void
1423 l2_st7_tout_203(struct FsmInst *fi, int event, void *arg)
1424 {
1425 	struct layer2 *l2 = fi->userdata;
1426 
1427 	if (test_bit(FLG_LAPD, &l2->flag) &&
1428 		test_bit(FLG_DCHAN_BUSY, &l2->flag)) {
1429 		mISDN_FsmAddTimer(&l2->t203, l2->T203, EV_L2_T203, NULL, 9);
1430 		return;
1431 	}
1432 	mISDN_FsmChangeState(fi, ST_L2_8);
1433 	transmit_enquiry(l2);
1434 	l2->rc = 0;
1435 }
1436 
1437 static void
1438 l2_pull_iqueue(struct FsmInst *fi, int event, void *arg)
1439 {
1440 	struct layer2	*l2 = fi->userdata;
1441 	struct sk_buff	*skb, *nskb, *oskb;
1442 	u_char		header[MAX_L2HEADER_LEN];
1443 	u_int		i, p1;
1444 
1445 	if (!cansend(l2))
1446 		return;
1447 
1448 	skb = skb_dequeue(&l2->i_queue);
1449 	if (!skb)
1450 		return;
1451 
1452 	if (test_bit(FLG_MOD128, &l2->flag))
1453 		p1 = (l2->vs - l2->va) % 128;
1454 	else
1455 		p1 = (l2->vs - l2->va) % 8;
1456 	p1 = (p1 + l2->sow) % l2->window;
1457 	if (l2->windowar[p1]) {
1458 		printk(KERN_WARNING "isdnl2 try overwrite ack queue entry %d\n",
1459 		    p1);
1460 		dev_kfree_skb(l2->windowar[p1]);
1461 	}
1462 	l2->windowar[p1] = skb;
1463 	i = sethdraddr(l2, header, CMD);
1464 	if (test_bit(FLG_MOD128, &l2->flag)) {
1465 		header[i++] = l2->vs << 1;
1466 		header[i++] = l2->vr << 1;
1467 		l2->vs = (l2->vs + 1) % 128;
1468 	} else {
1469 		header[i++] = (l2->vr << 5) | (l2->vs << 1);
1470 		l2->vs = (l2->vs + 1) % 8;
1471 	}
1472 
1473 	nskb = skb_clone(skb, GFP_ATOMIC);
1474 	p1 = skb_headroom(nskb);
1475 	if (p1 >= i)
1476 		memcpy(skb_push(nskb, i), header, i);
1477 	else {
1478 		printk(KERN_WARNING
1479 		    "isdnl2 pull_iqueue skb header(%d/%d) too short\n", i, p1);
1480 		oskb = nskb;
1481 		nskb = mI_alloc_skb(oskb->len + i, GFP_ATOMIC);
1482 		if (!nskb) {
1483 			dev_kfree_skb(oskb);
1484 			printk(KERN_WARNING "%s: no skb mem\n", __func__);
1485 			return;
1486 		}
1487 		memcpy(skb_put(nskb, i), header, i);
1488 		memcpy(skb_put(nskb, oskb->len), oskb->data, oskb->len);
1489 		dev_kfree_skb(oskb);
1490 	}
1491 	l2down(l2, PH_DATA_REQ, l2_newid(l2), nskb);
1492 	test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1493 	if (!test_and_set_bit(FLG_T200_RUN, &l2->flag)) {
1494 		mISDN_FsmDelTimer(&l2->t203, 13);
1495 		mISDN_FsmAddTimer(&l2->t200, l2->T200, EV_L2_T200, NULL, 11);
1496 	}
1497 }
1498 
1499 static void
1500 l2_st8_got_super(struct FsmInst *fi, int event, void *arg)
1501 {
1502 	struct layer2 *l2 = fi->userdata;
1503 	struct sk_buff *skb = arg;
1504 	int PollFlag, rsp, rnr = 0;
1505 	unsigned int nr;
1506 
1507 	rsp = *skb->data & 0x2;
1508 	if (test_bit(FLG_ORIG, &l2->flag))
1509 		rsp = !rsp;
1510 
1511 	skb_pull(skb, l2addrsize(l2));
1512 
1513 	if (IsRNR(skb->data, l2)) {
1514 		set_peer_busy(l2);
1515 		rnr = 1;
1516 	} else
1517 		clear_peer_busy(l2);
1518 
1519 	if (test_bit(FLG_MOD128, &l2->flag)) {
1520 		PollFlag = (skb->data[1] & 0x1) == 0x1;
1521 		nr = skb->data[1] >> 1;
1522 	} else {
1523 		PollFlag = (skb->data[0] & 0x10);
1524 		nr = (skb->data[0] >> 5) & 0x7;
1525 	}
1526 	dev_kfree_skb(skb);
1527 	if (rsp && PollFlag) {
1528 		if (legalnr(l2, nr)) {
1529 			if (rnr) {
1530 				restart_t200(l2, 15);
1531 			} else {
1532 				stop_t200(l2, 16);
1533 				mISDN_FsmAddTimer(&l2->t203, l2->T203,
1534 					    EV_L2_T203, NULL, 5);
1535 				setva(l2, nr);
1536 			}
1537 			invoke_retransmission(l2, nr);
1538 			mISDN_FsmChangeState(fi, ST_L2_7);
1539 			if (skb_queue_len(&l2->i_queue) && cansend(l2))
1540 				mISDN_FsmEvent(fi, EV_L2_ACK_PULL, NULL);
1541 		} else
1542 			nrerrorrecovery(fi);
1543 	} else {
1544 		if (!rsp && PollFlag)
1545 			enquiry_response(l2);
1546 		if (legalnr(l2, nr))
1547 			setva(l2, nr);
1548 		else
1549 			nrerrorrecovery(fi);
1550 	}
1551 }
1552 
1553 static void
1554 l2_got_FRMR(struct FsmInst *fi, int event, void *arg)
1555 {
1556 	struct layer2 *l2 = fi->userdata;
1557 	struct sk_buff *skb = arg;
1558 
1559 	skb_pull(skb, l2addrsize(l2) + 1);
1560 
1561 	if (!(skb->data[0] & 1) || ((skb->data[0] & 3) == 1) || /* I or S */
1562 	    (IsUA(skb->data) && (fi->state == ST_L2_7))) {
1563 		l2mgr(l2, MDL_ERROR_IND, (void *) 'K');
1564 		establishlink(fi);
1565 		test_and_clear_bit(FLG_L3_INIT, &l2->flag);
1566 	}
1567 	dev_kfree_skb(skb);
1568 }
1569 
1570 static void
1571 l2_st24_tei_remove(struct FsmInst *fi, int event, void *arg)
1572 {
1573 	struct layer2 *l2 = fi->userdata;
1574 
1575 	skb_queue_purge(&l2->ui_queue);
1576 	l2->tei = GROUP_TEI;
1577 	mISDN_FsmChangeState(fi, ST_L2_1);
1578 }
1579 
1580 static void
1581 l2_st3_tei_remove(struct FsmInst *fi, int event, void *arg)
1582 {
1583 	struct layer2 *l2 = fi->userdata;
1584 
1585 	skb_queue_purge(&l2->ui_queue);
1586 	l2->tei = GROUP_TEI;
1587 	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
1588 	mISDN_FsmChangeState(fi, ST_L2_1);
1589 }
1590 
1591 static void
1592 l2_st5_tei_remove(struct FsmInst *fi, int event, void *arg)
1593 {
1594 	struct layer2 *l2 = fi->userdata;
1595 
1596 	skb_queue_purge(&l2->i_queue);
1597 	skb_queue_purge(&l2->ui_queue);
1598 	freewin(l2);
1599 	l2->tei = GROUP_TEI;
1600 	stop_t200(l2, 17);
1601 	st5_dl_release_l2l3(l2);
1602 	mISDN_FsmChangeState(fi, ST_L2_1);
1603 }
1604 
1605 static void
1606 l2_st6_tei_remove(struct FsmInst *fi, int event, void *arg)
1607 {
1608 	struct layer2 *l2 = fi->userdata;
1609 
1610 	skb_queue_purge(&l2->ui_queue);
1611 	l2->tei = GROUP_TEI;
1612 	stop_t200(l2, 18);
1613 	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
1614 	mISDN_FsmChangeState(fi, ST_L2_1);
1615 }
1616 
1617 static void
1618 l2_tei_remove(struct FsmInst *fi, int event, void *arg)
1619 {
1620 	struct layer2 *l2 = fi->userdata;
1621 
1622 	skb_queue_purge(&l2->i_queue);
1623 	skb_queue_purge(&l2->ui_queue);
1624 	freewin(l2);
1625 	l2->tei = GROUP_TEI;
1626 	stop_t200(l2, 17);
1627 	mISDN_FsmDelTimer(&l2->t203, 19);
1628 	l2up_create(l2, DL_RELEASE_IND, 0, NULL);
1629 /*	mISDN_queue_data(&l2->inst, l2->inst.id | MSG_BROADCAST,
1630  *		MGR_SHORTSTATUS_IND, SSTATUS_L2_RELEASED,
1631  *		0, NULL, 0);
1632  */
1633 	mISDN_FsmChangeState(fi, ST_L2_1);
1634 }
1635 
1636 static void
1637 l2_st14_persistant_da(struct FsmInst *fi, int event, void *arg)
1638 {
1639 	struct layer2 *l2 = fi->userdata;
1640 	struct sk_buff *skb = arg;
1641 
1642 	skb_queue_purge(&l2->i_queue);
1643 	skb_queue_purge(&l2->ui_queue);
1644 	if (test_and_clear_bit(FLG_ESTAB_PEND, &l2->flag))
1645 		l2up(l2, DL_RELEASE_IND, skb);
1646 	else
1647 		dev_kfree_skb(skb);
1648 }
1649 
1650 static void
1651 l2_st5_persistant_da(struct FsmInst *fi, int event, void *arg)
1652 {
1653 	struct layer2 *l2 = fi->userdata;
1654 	struct sk_buff *skb = arg;
1655 
1656 	skb_queue_purge(&l2->i_queue);
1657 	skb_queue_purge(&l2->ui_queue);
1658 	freewin(l2);
1659 	stop_t200(l2, 19);
1660 	st5_dl_release_l2l3(l2);
1661 	mISDN_FsmChangeState(fi, ST_L2_4);
1662 	if (l2->tm)
1663 		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1664 	dev_kfree_skb(skb);
1665 }
1666 
1667 static void
1668 l2_st6_persistant_da(struct FsmInst *fi, int event, void *arg)
1669 {
1670 	struct layer2 *l2 = fi->userdata;
1671 	struct sk_buff *skb = arg;
1672 
1673 	skb_queue_purge(&l2->ui_queue);
1674 	stop_t200(l2, 20);
1675 	l2up(l2, DL_RELEASE_CNF, skb);
1676 	mISDN_FsmChangeState(fi, ST_L2_4);
1677 	if (l2->tm)
1678 		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1679 }
1680 
1681 static void
1682 l2_persistant_da(struct FsmInst *fi, int event, void *arg)
1683 {
1684 	struct layer2 *l2 = fi->userdata;
1685 	struct sk_buff *skb = arg;
1686 
1687 	skb_queue_purge(&l2->i_queue);
1688 	skb_queue_purge(&l2->ui_queue);
1689 	freewin(l2);
1690 	stop_t200(l2, 19);
1691 	mISDN_FsmDelTimer(&l2->t203, 19);
1692 	l2up(l2, DL_RELEASE_IND, skb);
1693 	mISDN_FsmChangeState(fi, ST_L2_4);
1694 	if (l2->tm)
1695 		l2_tei(l2, MDL_STATUS_DOWN_IND, 0);
1696 }
1697 
1698 static void
1699 l2_set_own_busy(struct FsmInst *fi, int event, void *arg)
1700 {
1701 	struct layer2 *l2 = fi->userdata;
1702 	struct sk_buff *skb = arg;
1703 
1704 	if (!test_and_set_bit(FLG_OWN_BUSY, &l2->flag)) {
1705 		enquiry_cr(l2, RNR, RSP, 0);
1706 		test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1707 	}
1708 	if (skb)
1709 		dev_kfree_skb(skb);
1710 }
1711 
1712 static void
1713 l2_clear_own_busy(struct FsmInst *fi, int event, void *arg)
1714 {
1715 	struct layer2 *l2 = fi->userdata;
1716 	struct sk_buff *skb = arg;
1717 
1718 	if (!test_and_clear_bit(FLG_OWN_BUSY, &l2->flag)) {
1719 		enquiry_cr(l2, RR, RSP, 0);
1720 		test_and_clear_bit(FLG_ACK_PEND, &l2->flag);
1721 	}
1722 	if (skb)
1723 		dev_kfree_skb(skb);
1724 }
1725 
1726 static void
1727 l2_frame_error(struct FsmInst *fi, int event, void *arg)
1728 {
1729 	struct layer2 *l2 = fi->userdata;
1730 
1731 	l2mgr(l2, MDL_ERROR_IND, arg);
1732 }
1733 
1734 static void
1735 l2_frame_error_reest(struct FsmInst *fi, int event, void *arg)
1736 {
1737 	struct layer2 *l2 = fi->userdata;
1738 
1739 	l2mgr(l2, MDL_ERROR_IND, arg);
1740 	establishlink(fi);
1741 	test_and_clear_bit(FLG_L3_INIT, &l2->flag);
1742 }
1743 
1744 static struct FsmNode L2FnList[] =
1745 {
1746 	{ST_L2_1, EV_L2_DL_ESTABLISH_REQ, l2_mdl_assign},
1747 	{ST_L2_2, EV_L2_DL_ESTABLISH_REQ, l2_go_st3},
1748 	{ST_L2_4, EV_L2_DL_ESTABLISH_REQ, l2_establish},
1749 	{ST_L2_5, EV_L2_DL_ESTABLISH_REQ, l2_discard_i_setl3},
1750 	{ST_L2_7, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
1751 	{ST_L2_8, EV_L2_DL_ESTABLISH_REQ, l2_l3_reestablish},
1752 	{ST_L2_4, EV_L2_DL_RELEASE_REQ, l2_release},
1753 	{ST_L2_5, EV_L2_DL_RELEASE_REQ, l2_pend_rel},
1754 	{ST_L2_7, EV_L2_DL_RELEASE_REQ, l2_disconnect},
1755 	{ST_L2_8, EV_L2_DL_RELEASE_REQ, l2_disconnect},
1756 	{ST_L2_5, EV_L2_DL_DATA, l2_feed_i_if_reest},
1757 	{ST_L2_7, EV_L2_DL_DATA, l2_feed_i_pull},
1758 	{ST_L2_8, EV_L2_DL_DATA, l2_feed_iqueue},
1759 	{ST_L2_1, EV_L2_DL_UNITDATA, l2_queue_ui_assign},
1760 	{ST_L2_2, EV_L2_DL_UNITDATA, l2_queue_ui},
1761 	{ST_L2_3, EV_L2_DL_UNITDATA, l2_queue_ui},
1762 	{ST_L2_4, EV_L2_DL_UNITDATA, l2_send_ui},
1763 	{ST_L2_5, EV_L2_DL_UNITDATA, l2_send_ui},
1764 	{ST_L2_6, EV_L2_DL_UNITDATA, l2_send_ui},
1765 	{ST_L2_7, EV_L2_DL_UNITDATA, l2_send_ui},
1766 	{ST_L2_8, EV_L2_DL_UNITDATA, l2_send_ui},
1767 	{ST_L2_1, EV_L2_MDL_ASSIGN, l2_got_tei},
1768 	{ST_L2_2, EV_L2_MDL_ASSIGN, l2_got_tei},
1769 	{ST_L2_3, EV_L2_MDL_ASSIGN, l2_got_tei},
1770 	{ST_L2_2, EV_L2_MDL_ERROR, l2_st24_tei_remove},
1771 	{ST_L2_3, EV_L2_MDL_ERROR, l2_st3_tei_remove},
1772 	{ST_L2_4, EV_L2_MDL_REMOVE, l2_st24_tei_remove},
1773 	{ST_L2_5, EV_L2_MDL_REMOVE, l2_st5_tei_remove},
1774 	{ST_L2_6, EV_L2_MDL_REMOVE, l2_st6_tei_remove},
1775 	{ST_L2_7, EV_L2_MDL_REMOVE, l2_tei_remove},
1776 	{ST_L2_8, EV_L2_MDL_REMOVE, l2_tei_remove},
1777 	{ST_L2_4, EV_L2_SABME, l2_start_multi},
1778 	{ST_L2_5, EV_L2_SABME, l2_send_UA},
1779 	{ST_L2_6, EV_L2_SABME, l2_send_DM},
1780 	{ST_L2_7, EV_L2_SABME, l2_restart_multi},
1781 	{ST_L2_8, EV_L2_SABME, l2_restart_multi},
1782 	{ST_L2_4, EV_L2_DISC, l2_send_DM},
1783 	{ST_L2_5, EV_L2_DISC, l2_send_DM},
1784 	{ST_L2_6, EV_L2_DISC, l2_send_UA},
1785 	{ST_L2_7, EV_L2_DISC, l2_stop_multi},
1786 	{ST_L2_8, EV_L2_DISC, l2_stop_multi},
1787 	{ST_L2_4, EV_L2_UA, l2_mdl_error_ua},
1788 	{ST_L2_5, EV_L2_UA, l2_connected},
1789 	{ST_L2_6, EV_L2_UA, l2_released},
1790 	{ST_L2_7, EV_L2_UA, l2_mdl_error_ua},
1791 	{ST_L2_8, EV_L2_UA, l2_mdl_error_ua},
1792 	{ST_L2_4, EV_L2_DM, l2_reestablish},
1793 	{ST_L2_5, EV_L2_DM, l2_st5_dm_release},
1794 	{ST_L2_6, EV_L2_DM, l2_st6_dm_release},
1795 	{ST_L2_7, EV_L2_DM, l2_mdl_error_dm},
1796 	{ST_L2_8, EV_L2_DM, l2_st8_mdl_error_dm},
1797 	{ST_L2_1, EV_L2_UI, l2_got_ui},
1798 	{ST_L2_2, EV_L2_UI, l2_got_ui},
1799 	{ST_L2_3, EV_L2_UI, l2_got_ui},
1800 	{ST_L2_4, EV_L2_UI, l2_got_ui},
1801 	{ST_L2_5, EV_L2_UI, l2_got_ui},
1802 	{ST_L2_6, EV_L2_UI, l2_got_ui},
1803 	{ST_L2_7, EV_L2_UI, l2_got_ui},
1804 	{ST_L2_8, EV_L2_UI, l2_got_ui},
1805 	{ST_L2_7, EV_L2_FRMR, l2_got_FRMR},
1806 	{ST_L2_8, EV_L2_FRMR, l2_got_FRMR},
1807 	{ST_L2_7, EV_L2_SUPER, l2_st7_got_super},
1808 	{ST_L2_8, EV_L2_SUPER, l2_st8_got_super},
1809 	{ST_L2_7, EV_L2_I, l2_got_iframe},
1810 	{ST_L2_8, EV_L2_I, l2_got_iframe},
1811 	{ST_L2_5, EV_L2_T200, l2_st5_tout_200},
1812 	{ST_L2_6, EV_L2_T200, l2_st6_tout_200},
1813 	{ST_L2_7, EV_L2_T200, l2_st7_tout_200},
1814 	{ST_L2_8, EV_L2_T200, l2_st8_tout_200},
1815 	{ST_L2_7, EV_L2_T203, l2_st7_tout_203},
1816 	{ST_L2_7, EV_L2_ACK_PULL, l2_pull_iqueue},
1817 	{ST_L2_7, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
1818 	{ST_L2_8, EV_L2_SET_OWN_BUSY, l2_set_own_busy},
1819 	{ST_L2_7, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
1820 	{ST_L2_8, EV_L2_CLEAR_OWN_BUSY, l2_clear_own_busy},
1821 	{ST_L2_4, EV_L2_FRAME_ERROR, l2_frame_error},
1822 	{ST_L2_5, EV_L2_FRAME_ERROR, l2_frame_error},
1823 	{ST_L2_6, EV_L2_FRAME_ERROR, l2_frame_error},
1824 	{ST_L2_7, EV_L2_FRAME_ERROR, l2_frame_error_reest},
1825 	{ST_L2_8, EV_L2_FRAME_ERROR, l2_frame_error_reest},
1826 	{ST_L2_1, EV_L1_DEACTIVATE, l2_st14_persistant_da},
1827 	{ST_L2_2, EV_L1_DEACTIVATE, l2_st24_tei_remove},
1828 	{ST_L2_3, EV_L1_DEACTIVATE, l2_st3_tei_remove},
1829 	{ST_L2_4, EV_L1_DEACTIVATE, l2_st14_persistant_da},
1830 	{ST_L2_5, EV_L1_DEACTIVATE, l2_st5_persistant_da},
1831 	{ST_L2_6, EV_L1_DEACTIVATE, l2_st6_persistant_da},
1832 	{ST_L2_7, EV_L1_DEACTIVATE, l2_persistant_da},
1833 	{ST_L2_8, EV_L1_DEACTIVATE, l2_persistant_da},
1834 };
1835 
1836 static int
1837 ph_data_indication(struct layer2 *l2, struct mISDNhead *hh, struct sk_buff *skb)
1838 {
1839 	u_char	*datap = skb->data;
1840 	int	ret = -EINVAL;
1841 	int	psapi, ptei;
1842 	u_int	l;
1843 	int	c = 0;
1844 
1845 	l = l2addrsize(l2);
1846 	if (skb->len <= l) {
1847 		mISDN_FsmEvent(&l2->l2m, EV_L2_FRAME_ERROR, (void *) 'N');
1848 		return ret;
1849 	}
1850 	if (test_bit(FLG_LAPD, &l2->flag)) { /* Maybe not needed */
1851 		psapi = *datap++;
1852 		ptei = *datap++;
1853 		if ((psapi & 1) || !(ptei & 1)) {
1854 			printk(KERN_WARNING
1855 			    "l2 D-channel frame wrong EA0/EA1\n");
1856 			return ret;
1857 		}
1858 		psapi >>= 2;
1859 		ptei >>= 1;
1860 		if (psapi != l2->sapi) {
1861 			/* not our bussiness */
1862 			if (*debug & DEBUG_L2)
1863 				printk(KERN_DEBUG "%s: sapi %d/%d mismatch\n",
1864 					__func__, psapi, l2->sapi);
1865 			dev_kfree_skb(skb);
1866 			return 0;
1867 		}
1868 		if ((ptei != l2->tei) && (ptei != GROUP_TEI)) {
1869 			/* not our bussiness */
1870 			if (*debug & DEBUG_L2)
1871 				printk(KERN_DEBUG "%s: tei %d/%d mismatch\n",
1872 					__func__, ptei, l2->tei);
1873 			dev_kfree_skb(skb);
1874 			return 0;
1875 		}
1876 	} else
1877 		datap += l;
1878 	if (!(*datap & 1)) {	/* I-Frame */
1879 		c = iframe_error(l2, skb);
1880 		if (!c)
1881 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_I, skb);
1882 	} else if (IsSFrame(datap, l2)) {	/* S-Frame */
1883 		c = super_error(l2, skb);
1884 		if (!c)
1885 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_SUPER, skb);
1886 	} else if (IsUI(datap)) {
1887 		c = UI_error(l2, skb);
1888 		if (!c)
1889 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_UI, skb);
1890 	} else if (IsSABME(datap, l2)) {
1891 		c = unnum_error(l2, skb, CMD);
1892 		if (!c)
1893 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_SABME, skb);
1894 	} else if (IsUA(datap)) {
1895 		c = unnum_error(l2, skb, RSP);
1896 		if (!c)
1897 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_UA, skb);
1898 	} else if (IsDISC(datap)) {
1899 		c = unnum_error(l2, skb, CMD);
1900 		if (!c)
1901 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DISC, skb);
1902 	} else if (IsDM(datap)) {
1903 		c = unnum_error(l2, skb, RSP);
1904 		if (!c)
1905 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DM, skb);
1906 	} else if (IsFRMR(datap)) {
1907 		c = FRMR_error(l2, skb);
1908 		if (!c)
1909 			ret = mISDN_FsmEvent(&l2->l2m, EV_L2_FRMR, skb);
1910 	} else
1911 		c = 'L';
1912 	if (c) {
1913 		printk(KERN_WARNING "l2 D-channel frame error %c\n", c);
1914 		mISDN_FsmEvent(&l2->l2m, EV_L2_FRAME_ERROR, (void *)(long)c);
1915 	}
1916 	return ret;
1917 }
1918 
1919 static int
1920 l2_send(struct mISDNchannel *ch, struct sk_buff *skb)
1921 {
1922 	struct layer2		*l2 = container_of(ch, struct layer2, ch);
1923 	struct mISDNhead	*hh =  mISDN_HEAD_P(skb);
1924 	int 			ret = -EINVAL;
1925 
1926 	if (*debug & DEBUG_L2_RECV)
1927 		printk(KERN_DEBUG "%s: prim(%x) id(%x) sapi(%d) tei(%d)\n",
1928 		    __func__, hh->prim, hh->id, l2->sapi, l2->tei);
1929 	switch (hh->prim) {
1930 	case PH_DATA_IND:
1931 		ret = ph_data_indication(l2, hh, skb);
1932 		break;
1933 	case PH_DATA_CNF:
1934 		ret = ph_data_confirm(l2, hh, skb);
1935 		break;
1936 	case PH_ACTIVATE_IND:
1937 		test_and_set_bit(FLG_L1_ACTIV, &l2->flag);
1938 		l2up_create(l2, MPH_ACTIVATE_IND, 0, NULL);
1939 		if (test_and_clear_bit(FLG_ESTAB_PEND, &l2->flag))
1940 			ret = mISDN_FsmEvent(&l2->l2m,
1941 				EV_L2_DL_ESTABLISH_REQ, skb);
1942 		break;
1943 	case PH_DEACTIVATE_IND:
1944 		test_and_clear_bit(FLG_L1_ACTIV, &l2->flag);
1945 		l2up_create(l2, MPH_DEACTIVATE_IND, 0, NULL);
1946 		ret = mISDN_FsmEvent(&l2->l2m, EV_L1_DEACTIVATE, skb);
1947 		break;
1948 	case MPH_INFORMATION_IND:
1949 		if (!l2->up)
1950 			break;
1951 		ret = l2->up->send(l2->up, skb);
1952 		break;
1953 	case DL_DATA_REQ:
1954 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_DATA, skb);
1955 		break;
1956 	case DL_UNITDATA_REQ:
1957 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_UNITDATA, skb);
1958 		break;
1959 	case DL_ESTABLISH_REQ:
1960 		if (test_bit(FLG_LAPB, &l2->flag))
1961 			test_and_set_bit(FLG_ORIG, &l2->flag);
1962 		if (test_bit(FLG_L1_ACTIV, &l2->flag)) {
1963 			if (test_bit(FLG_LAPD, &l2->flag) ||
1964 				test_bit(FLG_ORIG, &l2->flag))
1965 				ret = mISDN_FsmEvent(&l2->l2m,
1966 					EV_L2_DL_ESTABLISH_REQ, skb);
1967 		} else {
1968 			if (test_bit(FLG_LAPD, &l2->flag) ||
1969 				test_bit(FLG_ORIG, &l2->flag)) {
1970 				test_and_set_bit(FLG_ESTAB_PEND,
1971 					&l2->flag);
1972 			}
1973 			ret = l2down(l2, PH_ACTIVATE_REQ, l2_newid(l2),
1974 			    skb);
1975 		}
1976 		break;
1977 	case DL_RELEASE_REQ:
1978 		if (test_bit(FLG_LAPB, &l2->flag))
1979 			l2down_create(l2, PH_DEACTIVATE_REQ,
1980 				l2_newid(l2), 0, NULL);
1981 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_DL_RELEASE_REQ,
1982 		    skb);
1983 		break;
1984 	default:
1985 		if (*debug & DEBUG_L2)
1986 			l2m_debug(&l2->l2m, "l2 unknown pr %04x",
1987 			    hh->prim);
1988 	}
1989 	if (ret) {
1990 		dev_kfree_skb(skb);
1991 		ret = 0;
1992 	}
1993 	return ret;
1994 }
1995 
1996 int
1997 tei_l2(struct layer2 *l2, u_int cmd, u_long arg)
1998 {
1999 	int		ret = -EINVAL;
2000 
2001 	if (*debug & DEBUG_L2_TEI)
2002 		printk(KERN_DEBUG "%s: cmd(%x)\n", __func__, cmd);
2003 	switch (cmd) {
2004 	case (MDL_ASSIGN_REQ):
2005 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ASSIGN, (void *)arg);
2006 		break;
2007 	case (MDL_REMOVE_REQ):
2008 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_REMOVE, NULL);
2009 		break;
2010 	case (MDL_ERROR_IND):
2011 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ERROR, NULL);
2012 		break;
2013 	case (MDL_ERROR_RSP):
2014 		/* ETS 300-125 5.3.2.1 Test: TC13010 */
2015 		printk(KERN_NOTICE "MDL_ERROR|REQ (tei_l2)\n");
2016 		ret = mISDN_FsmEvent(&l2->l2m, EV_L2_MDL_ERROR, NULL);
2017 		break;
2018 	}
2019 	return ret;
2020 }
2021 
2022 static void
2023 release_l2(struct layer2 *l2)
2024 {
2025 	mISDN_FsmDelTimer(&l2->t200, 21);
2026 	mISDN_FsmDelTimer(&l2->t203, 16);
2027 	skb_queue_purge(&l2->i_queue);
2028 	skb_queue_purge(&l2->ui_queue);
2029 	skb_queue_purge(&l2->down_queue);
2030 	ReleaseWin(l2);
2031 	if (test_bit(FLG_LAPD, &l2->flag)) {
2032 		TEIrelease(l2);
2033 		if (l2->ch.st)
2034 			l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D,
2035 			    CLOSE_CHANNEL, NULL);
2036 	}
2037 	kfree(l2);
2038 }
2039 
2040 static int
2041 l2_ctrl(struct mISDNchannel *ch, u_int cmd, void *arg)
2042 {
2043 	struct layer2		*l2 = container_of(ch, struct layer2, ch);
2044 	u_int			info;
2045 
2046 	if (*debug & DEBUG_L2_CTRL)
2047 		printk(KERN_DEBUG "%s:(%x)\n", __func__, cmd);
2048 
2049 	switch (cmd) {
2050 	case OPEN_CHANNEL:
2051 		if (test_bit(FLG_LAPD, &l2->flag)) {
2052 			set_channel_address(&l2->ch, l2->sapi, l2->tei);
2053 			info = DL_INFO_L2_CONNECT;
2054 			l2up_create(l2, DL_INFORMATION_IND,
2055 			    sizeof(info), &info);
2056 		}
2057 		break;
2058 	case CLOSE_CHANNEL:
2059 		if (l2->ch.peer)
2060 			l2->ch.peer->ctrl(l2->ch.peer, CLOSE_CHANNEL, NULL);
2061 		release_l2(l2);
2062 		break;
2063 	}
2064 	return 0;
2065 }
2066 
2067 struct layer2 *
2068 create_l2(struct mISDNchannel *ch, u_int protocol, u_long options, int tei,
2069 		int sapi)
2070 {
2071 	struct layer2		*l2;
2072 	struct channel_req	rq;
2073 
2074 	l2 = kzalloc(sizeof(struct layer2), GFP_KERNEL);
2075 	if (!l2) {
2076 		printk(KERN_ERR "kzalloc layer2 failed\n");
2077 		return NULL;
2078 	}
2079 	l2->next_id = 1;
2080 	l2->down_id = MISDN_ID_NONE;
2081 	l2->up = ch;
2082 	l2->ch.st = ch->st;
2083 	l2->ch.send = l2_send;
2084 	l2->ch.ctrl = l2_ctrl;
2085 	switch (protocol) {
2086 	case ISDN_P_LAPD_NT:
2087 		test_and_set_bit(FLG_LAPD, &l2->flag);
2088 		test_and_set_bit(FLG_LAPD_NET, &l2->flag);
2089 		test_and_set_bit(FLG_MOD128, &l2->flag);
2090 		l2->sapi = sapi;
2091 		l2->maxlen = MAX_DFRAME_LEN;
2092 		if (test_bit(OPTION_L2_PMX, &options))
2093 			l2->window = 7;
2094 		else
2095 			l2->window = 1;
2096 		if (test_bit(OPTION_L2_PTP, &options))
2097 			test_and_set_bit(FLG_PTP, &l2->flag);
2098 		if (test_bit(OPTION_L2_FIXEDTEI, &options))
2099 			test_and_set_bit(FLG_FIXED_TEI, &l2->flag);
2100 		l2->tei = tei;
2101 		l2->T200 = 1000;
2102 		l2->N200 = 3;
2103 		l2->T203 = 10000;
2104 		if (test_bit(OPTION_L2_PMX, &options))
2105 			rq.protocol = ISDN_P_NT_E1;
2106 		else
2107 			rq.protocol = ISDN_P_NT_S0;
2108 		rq.adr.channel = 0;
2109 		l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D, OPEN_CHANNEL, &rq);
2110 		break;
2111 	case ISDN_P_LAPD_TE:
2112 		test_and_set_bit(FLG_LAPD, &l2->flag);
2113 		test_and_set_bit(FLG_MOD128, &l2->flag);
2114 		test_and_set_bit(FLG_ORIG, &l2->flag);
2115 		l2->sapi = sapi;
2116 		l2->maxlen = MAX_DFRAME_LEN;
2117 		if (test_bit(OPTION_L2_PMX, &options))
2118 			l2->window = 7;
2119 		else
2120 			l2->window = 1;
2121 		if (test_bit(OPTION_L2_PTP, &options))
2122 			test_and_set_bit(FLG_PTP, &l2->flag);
2123 		if (test_bit(OPTION_L2_FIXEDTEI, &options))
2124 			test_and_set_bit(FLG_FIXED_TEI, &l2->flag);
2125 		l2->tei = tei;
2126 		l2->T200 = 1000;
2127 		l2->N200 = 3;
2128 		l2->T203 = 10000;
2129 		if (test_bit(OPTION_L2_PMX, &options))
2130 			rq.protocol = ISDN_P_TE_E1;
2131 		else
2132 			rq.protocol = ISDN_P_TE_S0;
2133 		rq.adr.channel = 0;
2134 		l2->ch.st->dev->D.ctrl(&l2->ch.st->dev->D, OPEN_CHANNEL, &rq);
2135 		break;
2136 	case ISDN_P_B_X75SLP:
2137 		test_and_set_bit(FLG_LAPB, &l2->flag);
2138 		l2->window = 7;
2139 		l2->maxlen = MAX_DATA_SIZE;
2140 		l2->T200 = 1000;
2141 		l2->N200 = 4;
2142 		l2->T203 = 5000;
2143 		l2->addr.A = 3;
2144 		l2->addr.B = 1;
2145 		break;
2146 	default:
2147 		printk(KERN_ERR "layer2 create failed prt %x\n",
2148 			protocol);
2149 		kfree(l2);
2150 		return NULL;
2151 	}
2152 	skb_queue_head_init(&l2->i_queue);
2153 	skb_queue_head_init(&l2->ui_queue);
2154 	skb_queue_head_init(&l2->down_queue);
2155 	skb_queue_head_init(&l2->tmp_queue);
2156 	InitWin(l2);
2157 	l2->l2m.fsm = &l2fsm;
2158 	if (test_bit(FLG_LAPB, &l2->flag) ||
2159 		test_bit(FLG_PTP, &l2->flag) ||
2160 		test_bit(FLG_LAPD_NET, &l2->flag))
2161 		l2->l2m.state = ST_L2_4;
2162 	else
2163 		l2->l2m.state = ST_L2_1;
2164 	l2->l2m.debug = *debug;
2165 	l2->l2m.userdata = l2;
2166 	l2->l2m.userint = 0;
2167 	l2->l2m.printdebug = l2m_debug;
2168 
2169 	mISDN_FsmInitTimer(&l2->l2m, &l2->t200);
2170 	mISDN_FsmInitTimer(&l2->l2m, &l2->t203);
2171 	return l2;
2172 }
2173 
2174 static int
2175 x75create(struct channel_req *crq)
2176 {
2177 	struct layer2	*l2;
2178 
2179 	if (crq->protocol != ISDN_P_B_X75SLP)
2180 		return -EPROTONOSUPPORT;
2181 	l2 = create_l2(crq->ch, crq->protocol, 0, 0, 0);
2182 	if (!l2)
2183 		return -ENOMEM;
2184 	crq->ch = &l2->ch;
2185 	crq->protocol = ISDN_P_B_HDLC;
2186 	return 0;
2187 }
2188 
2189 static struct Bprotocol X75SLP = {
2190 	.Bprotocols = (1 << (ISDN_P_B_X75SLP & ISDN_P_B_MASK)),
2191 	.name = "X75SLP",
2192 	.create = x75create
2193 };
2194 
2195 int
2196 Isdnl2_Init(u_int *deb)
2197 {
2198 	debug = deb;
2199 	mISDN_register_Bprotocol(&X75SLP);
2200 	l2fsm.state_count = L2_STATE_COUNT;
2201 	l2fsm.event_count = L2_EVENT_COUNT;
2202 	l2fsm.strEvent = strL2Event;
2203 	l2fsm.strState = strL2State;
2204 	mISDN_FsmNew(&l2fsm, L2FnList, ARRAY_SIZE(L2FnList));
2205 	TEIInit(deb);
2206 	return 0;
2207 }
2208 
2209 void
2210 Isdnl2_cleanup(void)
2211 {
2212 	mISDN_unregister_Bprotocol(&X75SLP);
2213 	TEIFree();
2214 	mISDN_FsmFree(&l2fsm);
2215 }
2216 
2217