1 /*********************************************************************
2 *
3 * Filename: irlap_event.c
4 * Version: 0.9
5 * Description: IrLAP state machine implementation
6 * Status: Experimental.
7 * Author: Dag Brattli <dag@brattli.net>
8 * Created at: Sat Aug 16 00:59:29 1997
9 * Modified at: Sat Dec 25 21:07:57 1999
10 * Modified by: Dag Brattli <dag@brattli.net>
11 *
12 * Copyright (c) 1998-2000 Dag Brattli <dag@brattli.net>,
13 * Copyright (c) 1998 Thomas Davis <ratbert@radiks.net>
14 * All Rights Reserved.
15 * Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
16 *
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License as
19 * published by the Free Software Foundation; either version 2 of
20 * the License, or (at your option) any later version.
21 *
22 * Neither Dag Brattli nor University of Tromsų admit liability nor
23 * provide warranty for any of this software. This material is
24 * provided "AS-IS" and at no charge.
25 *
26 ********************************************************************/
27
28 #include <linux/config.h>
29 #include <linux/string.h>
30 #include <linux/kernel.h>
31 #include <linux/delay.h>
32 #include <linux/skbuff.h>
33
34 #include <net/irda/irda.h>
35 #include <net/irda/irlap_event.h>
36
37 #include <net/irda/timer.h>
38 #include <net/irda/irlap.h>
39 #include <net/irda/irlap_frame.h>
40 #include <net/irda/qos.h>
41 #include <net/irda/parameters.h>
42 #include <net/irda/irlmp.h> /* irlmp_flow_indication(), ... */
43
44 #include <net/irda/irda_device.h>
45
46 #ifdef CONFIG_IRDA_FAST_RR
47 int sysctl_fast_poll_increase = 50;
48 #endif
49
50 static int irlap_state_ndm (struct irlap_cb *self, IRLAP_EVENT event,
51 struct sk_buff *skb, struct irlap_info *info);
52 static int irlap_state_query (struct irlap_cb *self, IRLAP_EVENT event,
53 struct sk_buff *skb, struct irlap_info *info);
54 static int irlap_state_reply (struct irlap_cb *self, IRLAP_EVENT event,
55 struct sk_buff *skb, struct irlap_info *info);
56 static int irlap_state_conn (struct irlap_cb *self, IRLAP_EVENT event,
57 struct sk_buff *skb, struct irlap_info *info);
58 static int irlap_state_setup (struct irlap_cb *self, IRLAP_EVENT event,
59 struct sk_buff *skb, struct irlap_info *info);
60 static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
61 struct sk_buff *skb, struct irlap_info *info);
62 static int irlap_state_xmit_p (struct irlap_cb *self, IRLAP_EVENT event,
63 struct sk_buff *skb, struct irlap_info *info);
64 static int irlap_state_pclose (struct irlap_cb *self, IRLAP_EVENT event,
65 struct sk_buff *skb, struct irlap_info *info);
66 static int irlap_state_nrm_p (struct irlap_cb *self, IRLAP_EVENT event,
67 struct sk_buff *skb, struct irlap_info *info);
68 static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
69 struct sk_buff *skb, struct irlap_info *info);
70 static int irlap_state_reset (struct irlap_cb *self, IRLAP_EVENT event,
71 struct sk_buff *skb, struct irlap_info *info);
72 static int irlap_state_nrm_s (struct irlap_cb *self, IRLAP_EVENT event,
73 struct sk_buff *skb, struct irlap_info *info);
74 static int irlap_state_xmit_s (struct irlap_cb *self, IRLAP_EVENT event,
75 struct sk_buff *skb, struct irlap_info *info);
76 static int irlap_state_sclose (struct irlap_cb *self, IRLAP_EVENT event,
77 struct sk_buff *skb, struct irlap_info *info);
78 static int irlap_state_reset_check(struct irlap_cb *, IRLAP_EVENT event,
79 struct sk_buff *, struct irlap_info *);
80
81 #ifdef CONFIG_IRDA_DEBUG
82 static const char *irlap_event[] = {
83 "DISCOVERY_REQUEST",
84 "CONNECT_REQUEST",
85 "CONNECT_RESPONSE",
86 "DISCONNECT_REQUEST",
87 "DATA_REQUEST",
88 "RESET_REQUEST",
89 "RESET_RESPONSE",
90 "SEND_I_CMD",
91 "SEND_UI_FRAME",
92 "RECV_DISCOVERY_XID_CMD",
93 "RECV_DISCOVERY_XID_RSP",
94 "RECV_SNRM_CMD",
95 "RECV_TEST_CMD",
96 "RECV_TEST_RSP",
97 "RECV_UA_RSP",
98 "RECV_DM_RSP",
99 "RECV_RD_RSP",
100 "RECV_I_CMD",
101 "RECV_I_RSP",
102 "RECV_UI_FRAME",
103 "RECV_FRMR_RSP",
104 "RECV_RR_CMD",
105 "RECV_RR_RSP",
106 "RECV_RNR_CMD",
107 "RECV_RNR_RSP",
108 "RECV_REJ_CMD",
109 "RECV_REJ_RSP",
110 "RECV_SREJ_CMD",
111 "RECV_SREJ_RSP",
112 "RECV_DISC_CMD",
113 "SLOT_TIMER_EXPIRED",
114 "QUERY_TIMER_EXPIRED",
115 "FINAL_TIMER_EXPIRED",
116 "POLL_TIMER_EXPIRED",
117 "DISCOVERY_TIMER_EXPIRED",
118 "WD_TIMER_EXPIRED",
119 "BACKOFF_TIMER_EXPIRED",
120 "MEDIA_BUSY_TIMER_EXPIRED",
121 };
122 #endif /* CONFIG_IRDA_DEBUG */
123
124 const char *irlap_state[] = {
125 "LAP_NDM",
126 "LAP_QUERY",
127 "LAP_REPLY",
128 "LAP_CONN",
129 "LAP_SETUP",
130 "LAP_OFFLINE",
131 "LAP_XMIT_P",
132 "LAP_PCLOSE",
133 "LAP_NRM_P",
134 "LAP_RESET_WAIT",
135 "LAP_RESET",
136 "LAP_NRM_S",
137 "LAP_XMIT_S",
138 "LAP_SCLOSE",
139 "LAP_RESET_CHECK",
140 };
141
142 static int (*state[])(struct irlap_cb *self, IRLAP_EVENT event,
143 struct sk_buff *skb, struct irlap_info *info) =
144 {
145 irlap_state_ndm,
146 irlap_state_query,
147 irlap_state_reply,
148 irlap_state_conn,
149 irlap_state_setup,
150 irlap_state_offline,
151 irlap_state_xmit_p,
152 irlap_state_pclose,
153 irlap_state_nrm_p,
154 irlap_state_reset_wait,
155 irlap_state_reset,
156 irlap_state_nrm_s,
157 irlap_state_xmit_s,
158 irlap_state_sclose,
159 irlap_state_reset_check,
160 };
161
162 /*
163 * Function irda_poll_timer_expired (data)
164 *
165 * Poll timer has expired. Normally we must now send a RR frame to the
166 * remote device
167 */
168 static void irlap_poll_timer_expired(void *data)
169 {
170 struct irlap_cb *self = (struct irlap_cb *) data;
171
172 ASSERT(self != NULL, return;);
173 ASSERT(self->magic == LAP_MAGIC, return;);
174
175 irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
176 }
177
178 /*
179 * Calculate and set time before we will have to send back the pf bit
180 * to the peer. Use in primary.
181 * Make sure that state is XMIT_P/XMIT_S when calling this function
182 * (and that nobody messed up with the state). - Jean II
183 */
184 void irlap_start_poll_timer(struct irlap_cb *self, int timeout)
185 {
186 ASSERT(self != NULL, return;);
187 ASSERT(self->magic == LAP_MAGIC, return;);
188
189 #ifdef CONFIG_IRDA_FAST_RR
190 /*
191 * Send out the RR frames faster if our own transmit queue is empty, or
192 * if the peer is busy. The effect is a much faster conversation
193 */
194 if ((skb_queue_len(&self->txq) == 0) || (self->remote_busy)) {
195 if (self->fast_RR == TRUE) {
196 /*
197 * Assert that the fast poll timer has not reached the
198 * normal poll timer yet
199 */
200 if (self->fast_RR_timeout < timeout) {
201 /*
202 * FIXME: this should be a more configurable
203 * function
204 */
205 self->fast_RR_timeout +=
206 (sysctl_fast_poll_increase * HZ/1000);
207
208 /* Use this fast(er) timeout instead */
209 timeout = self->fast_RR_timeout;
210 }
211 } else {
212 self->fast_RR = TRUE;
213
214 /* Start with just 0 ms */
215 self->fast_RR_timeout = 0;
216 timeout = 0;
217 }
218 } else
219 self->fast_RR = FALSE;
220
221 IRDA_DEBUG(3, "%s(), timeout=%d (%ld)\n", __FUNCTION__, timeout, jiffies);
222 #endif /* CONFIG_IRDA_FAST_RR */
223
224 if (timeout == 0)
225 irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
226 else
227 irda_start_timer(&self->poll_timer, timeout, self,
228 irlap_poll_timer_expired);
229 }
230
231 /*
232 * Function irlap_do_event (event, skb, info)
233 *
234 * Rushes through the state machine without any delay. If state == XMIT
235 * then send queued data frames.
236 */
237 void irlap_do_event(struct irlap_cb *self, IRLAP_EVENT event,
238 struct sk_buff *skb, struct irlap_info *info)
239 {
240 int ret;
241
242 if (!self || self->magic != LAP_MAGIC)
243 return;
244
245 IRDA_DEBUG(3, "%s(), event = %s, state = %s\n", __FUNCTION__,
246 irlap_event[event], irlap_state[self->state]);
247
248 ret = (*state[self->state])(self, event, skb, info);
249
250 /*
251 * Check if there are any pending events that needs to be executed
252 */
253 switch (self->state) {
254 case LAP_XMIT_P: /* FALLTHROUGH */
255 case LAP_XMIT_S:
256 /*
257 * We just received the pf bit and are at the beginning
258 * of a new LAP transmit window.
259 * Check if there are any queued data frames, and do not
260 * try to disconnect link if we send any data frames, since
261 * that will change the state away form XMIT
262 */
263 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
264 skb_queue_len(&self->txq));
265
266 if (skb_queue_len(&self->txq)) {
267 /* Prevent race conditions with irlap_data_request() */
268 self->local_busy = TRUE;
269
270 /* Theory of operation.
271 * We send frames up to when we fill the window or
272 * reach line capacity. Those frames will queue up
273 * in the device queue, and the driver will slowly
274 * send them.
275 * After each frame that we send, we poll the higher
276 * layer for more data. It's the right time to do
277 * that because the link layer need to perform the mtt
278 * and then send the first frame, so we can afford
279 * to send a bit of time in kernel space.
280 * The explicit flow indication allow to minimise
281 * buffers (== lower latency), to avoid higher layer
282 * polling via timers (== less context switches) and
283 * to implement a crude scheduler - Jean II */
284
285 /* Try to send away all queued data frames */
286 while ((skb = skb_dequeue(&self->txq)) != NULL) {
287 /* Send one frame */
288 ret = (*state[self->state])(self, SEND_I_CMD,
289 skb, NULL);
290 /* Drop reference count.
291 * It will be increase as needed in
292 * irlap_send_data_xxx() */
293 kfree_skb(skb);
294
295 /* Poll the higher layers for one more frame */
296 irlmp_flow_indication(self->notify.instance,
297 FLOW_START);
298
299 if (ret == -EPROTO)
300 break; /* Try again later! */
301 }
302 /* Finished transmitting */
303 self->local_busy = FALSE;
304 } else if (self->disconnect_pending) {
305 self->disconnect_pending = FALSE;
306
307 ret = (*state[self->state])(self, DISCONNECT_REQUEST,
308 NULL, NULL);
309 }
310 break;
311 /* case LAP_NDM: */
312 /* case LAP_CONN: */
313 /* case LAP_RESET_WAIT: */
314 /* case LAP_RESET_CHECK: */
315 default:
316 break;
317 }
318 }
319
320 /*
321 * Function irlap_next_state (self, state)
322 *
323 * Switches state and provides debug information
324 *
325 */
326 static inline void irlap_next_state(struct irlap_cb *self, IRLAP_STATE state)
327 {
328 /*
329 if (!self || self->magic != LAP_MAGIC)
330 return;
331
332 IRDA_DEBUG(4, "next LAP state = %s\n", irlap_state[state]);
333 */
334 self->state = state;
335 }
336
337 /*
338 * Function irlap_state_ndm (event, skb, frame)
339 *
340 * NDM (Normal Disconnected Mode) state
341 *
342 */
343 static int irlap_state_ndm(struct irlap_cb *self, IRLAP_EVENT event,
344 struct sk_buff *skb, struct irlap_info *info)
345 {
346 discovery_t *discovery_rsp;
347 int ret = 0;
348
349 ASSERT(self != NULL, return -1;);
350 ASSERT(self->magic == LAP_MAGIC, return -1;);
351
352 switch (event) {
353 case CONNECT_REQUEST:
354 ASSERT(self->netdev != NULL, return -1;);
355
356 if (self->media_busy) {
357 /* Note : this will never happen, because we test
358 * media busy in irlap_connect_request() and
359 * postpone the event... - Jean II */
360 IRDA_DEBUG(0, "%s(), CONNECT_REQUEST: media busy!\n",
361 __FUNCTION__);
362
363 /* Always switch state before calling upper layers */
364 irlap_next_state(self, LAP_NDM);
365
366 irlap_disconnect_indication(self, LAP_MEDIA_BUSY);
367 } else {
368 irlap_send_snrm_frame(self, &self->qos_rx);
369
370 /* Start Final-bit timer */
371 irlap_start_final_timer(self, self->final_timeout);
372
373 self->retry_count = 0;
374 irlap_next_state(self, LAP_SETUP);
375 }
376 break;
377 case RECV_SNRM_CMD:
378 /* Check if the frame contains and I field */
379 if (info) {
380 self->daddr = info->daddr;
381 self->caddr = info->caddr;
382
383 irlap_next_state(self, LAP_CONN);
384
385 irlap_connect_indication(self, skb);
386 } else {
387 IRDA_DEBUG(0, "%s(), SNRM frame does not "
388 "contain an I field!\n", __FUNCTION__);
389 }
390 break;
391 case DISCOVERY_REQUEST:
392 ASSERT(info != NULL, return -1;);
393
394 if (self->media_busy) {
395 IRDA_DEBUG(0, "%s(), media busy!\n", __FUNCTION__);
396 /* irlap->log.condition = MEDIA_BUSY; */
397
398 /* This will make IrLMP try again */
399 irlap_discovery_confirm(self, NULL);
400 /* Note : the discovery log is not cleaned up here,
401 * it will be done in irlap_discovery_request()
402 * Jean II */
403 return 0;
404 }
405
406 self->S = info->S;
407 self->s = info->s;
408 irlap_send_discovery_xid_frame(self, info->S, info->s, TRUE,
409 info->discovery);
410 self->frame_sent = FALSE;
411 self->s++;
412
413 irlap_start_slot_timer(self, self->slot_timeout);
414 irlap_next_state(self, LAP_QUERY);
415 break;
416 case RECV_DISCOVERY_XID_CMD:
417 ASSERT(info != NULL, return -1;);
418
419 /* Assert that this is not the final slot */
420 if (info->s <= info->S) {
421 self->slot = irlap_generate_rand_time_slot(info->S,
422 info->s);
423 if (self->slot == info->s) {
424 discovery_rsp = irlmp_get_discovery_response();
425 discovery_rsp->data.daddr = info->daddr;
426
427 irlap_send_discovery_xid_frame(self, info->S,
428 self->slot,
429 FALSE,
430 discovery_rsp);
431 self->frame_sent = TRUE;
432 } else
433 self->frame_sent = FALSE;
434
435 /*
436 * Remember to multiply the query timeout value with
437 * the number of slots used
438 */
439 irlap_start_query_timer(self, QUERY_TIMEOUT*info->S);
440 irlap_next_state(self, LAP_REPLY);
441 } else {
442 /* This is the final slot. How is it possible ?
443 * This would happen is both discoveries are just slightly
444 * offset (if they are in sync, all packets are lost).
445 * Most often, all the discovery requests will be received
446 * in QUERY state (see my comment there), except for the
447 * last frame that will come here.
448 * The big trouble when it happen is that active discovery
449 * doesn't happen, because nobody answer the discoveries
450 * frame of the other guy, so the log shows up empty.
451 * What should we do ?
452 * Not much. It's too late to answer those discovery frames,
453 * so we just pass the info to IrLMP who will put it in the
454 * log (and post an event).
455 * Jean II
456 */
457 IRDA_DEBUG(1, "%s(), Receiving final discovery request, missed the discovery slots :-(\n", __FUNCTION__);
458
459 /* Last discovery request -> in the log */
460 irlap_discovery_indication(self, info->discovery);
461 }
462 break;
463 case MEDIA_BUSY_TIMER_EXPIRED:
464 /* A bunch of events may be postponed because the media is
465 * busy (usually immediately after we close a connection),
466 * or while we are doing discovery (state query/reply).
467 * In all those cases, the media busy flag will be cleared
468 * when it's OK for us to process those postponed events.
469 * This event is not mentioned in the state machines in the
470 * IrLAP spec. It's because they didn't consider Ultra and
471 * postponing connection request is optional.
472 * Jean II */
473 #ifdef CONFIG_IRDA_ULTRA
474 /* Send any pending Ultra frames if any */
475 if (!skb_queue_empty(&self->txq_ultra)) {
476 /* We don't send the frame, just post an event.
477 * Also, previously this code was in timer.c...
478 * Jean II */
479 ret = (*state[self->state])(self, SEND_UI_FRAME,
480 NULL, NULL);
481 }
482 #endif /* CONFIG_IRDA_ULTRA */
483 /* Check if we should try to connect.
484 * This code was previously in irlap_do_event() */
485 if (self->connect_pending) {
486 self->connect_pending = FALSE;
487
488 /* This one *should* not pend in this state, except
489 * if a socket try to connect and immediately
490 * disconnect. - clear - Jean II */
491 if (self->disconnect_pending)
492 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
493 else
494 ret = (*state[self->state])(self,
495 CONNECT_REQUEST,
496 NULL, NULL);
497 self->disconnect_pending = FALSE;
498 }
499 /* Note : one way to test if this code works well (including
500 * media busy and small busy) is to create a user space
501 * application generating an Ultra packet every 3.05 sec (or
502 * 2.95 sec) and to see how it interact with discovery.
503 * It's fairly easy to check that no packet is lost, that the
504 * packets are postponed during discovery and that after
505 * discovery indication you have a 100ms "gap".
506 * As connection request and Ultra are now processed the same
507 * way, this avoid the tedious job of trying IrLAP connection
508 * in all those cases...
509 * Jean II */
510 break;
511 #ifdef CONFIG_IRDA_ULTRA
512 case SEND_UI_FRAME:
513 {
514 int i;
515 /* Only allowed to repeat an operation twice */
516 for (i=0; ((i<2) && (self->media_busy == FALSE)); i++) {
517 skb = skb_dequeue(&self->txq_ultra);
518 if (skb)
519 irlap_send_ui_frame(self, skb, CBROADCAST,
520 CMD_FRAME);
521 else
522 break;
523 /* irlap_send_ui_frame() won't increase skb reference
524 * count, so no dev_kfree_skb() - Jean II */
525 }
526 if (i == 2) {
527 /* Force us to listen 500 ms again */
528 irda_device_set_media_busy(self->netdev, TRUE);
529 }
530 break;
531 }
532 case RECV_UI_FRAME:
533 /* Only accept broadcast frames in NDM mode */
534 if (info->caddr != CBROADCAST) {
535 IRDA_DEBUG(0, "%s(), not a broadcast frame!\n",
536 __FUNCTION__);
537 } else
538 irlap_unitdata_indication(self, skb);
539 break;
540 #endif /* CONFIG_IRDA_ULTRA */
541 case RECV_TEST_CMD:
542 /* Remove test frame header */
543 skb_pull(skb, sizeof(struct test_frame));
544
545 /*
546 * Send response. This skb will not be sent out again, and
547 * will only be used to send out the same info as the cmd
548 */
549 irlap_send_test_frame(self, CBROADCAST, info->daddr, skb);
550 break;
551 case RECV_TEST_RSP:
552 IRDA_DEBUG(0, "%s() not implemented!\n", __FUNCTION__);
553 break;
554 default:
555 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
556 irlap_event[event]);
557
558 ret = -1;
559 break;
560 }
561 return ret;
562 }
563
564 /*
565 * Function irlap_state_query (event, skb, info)
566 *
567 * QUERY state
568 *
569 */
570 static int irlap_state_query(struct irlap_cb *self, IRLAP_EVENT event,
571 struct sk_buff *skb, struct irlap_info *info)
572 {
573 int ret = 0;
574
575 ASSERT(self != NULL, return -1;);
576 ASSERT(self->magic == LAP_MAGIC, return -1;);
577
578 switch (event) {
579 case RECV_DISCOVERY_XID_RSP:
580 ASSERT(info != NULL, return -1;);
581 ASSERT(info->discovery != NULL, return -1;);
582
583 IRDA_DEBUG(4, "%s(), daddr=%08x\n", __FUNCTION__,
584 info->discovery->data.daddr);
585
586 if (!self->discovery_log) {
587 WARNING("%s: discovery log is gone! "
588 "maybe the discovery timeout has been set to "
589 "short?\n", __FUNCTION__);
590 break;
591 }
592 hashbin_insert(self->discovery_log,
593 (irda_queue_t *) info->discovery,
594 info->discovery->data.daddr, NULL);
595
596 /* Keep state */
597 /* irlap_next_state(self, LAP_QUERY); */
598
599 break;
600 case RECV_DISCOVERY_XID_CMD:
601 /* Yes, it is possible to receive those frames in this mode.
602 * Note that most often the last discovery request won't
603 * occur here but in NDM state (see my comment there).
604 * What should we do ?
605 * Not much. We are currently performing our own discovery,
606 * therefore we can't answer those frames. We don't want
607 * to change state either. We just pass the info to
608 * IrLMP who will put it in the log (and post an event).
609 * Jean II
610 */
611
612 ASSERT(info != NULL, return -1;);
613
614 IRDA_DEBUG(1, "%s(), Receiving discovery request (s = %d) while performing discovery :-(\n", __FUNCTION__, info->s);
615
616 /* Last discovery request ? */
617 if (info->s == 0xff)
618 irlap_discovery_indication(self, info->discovery);
619 break;
620 case SLOT_TIMER_EXPIRED:
621 /*
622 * Wait a little longer if we detect an incoming frame. This
623 * is not mentioned in the spec, but is a good thing to do,
624 * since we want to work even with devices that violate the
625 * timing requirements.
626 */
627 if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
628 IRDA_DEBUG(2, "%s(), device is slow to answer, "
629 "waiting some more!\n", __FUNCTION__);
630 irlap_start_slot_timer(self, MSECS_TO_JIFFIES(10));
631 self->add_wait = TRUE;
632 return ret;
633 }
634 self->add_wait = FALSE;
635
636 if (self->s < self->S) {
637 irlap_send_discovery_xid_frame(self, self->S,
638 self->s, TRUE,
639 self->discovery_cmd);
640 self->s++;
641 irlap_start_slot_timer(self, self->slot_timeout);
642
643 /* Keep state */
644 irlap_next_state(self, LAP_QUERY);
645 } else {
646 /* This is the final slot! */
647 irlap_send_discovery_xid_frame(self, self->S, 0xff,
648 TRUE,
649 self->discovery_cmd);
650
651 /* Always switch state before calling upper layers */
652 irlap_next_state(self, LAP_NDM);
653
654 /*
655 * We are now finished with the discovery procedure,
656 * so now we must return the results
657 */
658 irlap_discovery_confirm(self, self->discovery_log);
659
660 /* IrLMP should now have taken care of the log */
661 self->discovery_log = NULL;
662 }
663 break;
664 default:
665 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
666 irlap_event[event]);
667
668 ret = -1;
669 break;
670 }
671 return ret;
672 }
673
674 /*
675 * Function irlap_state_reply (self, event, skb, info)
676 *
677 * REPLY, we have received a XID discovery frame from a device and we
678 * are waiting for the right time slot to send a response XID frame
679 *
680 */
681 static int irlap_state_reply(struct irlap_cb *self, IRLAP_EVENT event,
682 struct sk_buff *skb, struct irlap_info *info)
683 {
684 discovery_t *discovery_rsp;
685 int ret=0;
686
687 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
688
689 ASSERT(self != NULL, return -1;);
690 ASSERT(self->magic == LAP_MAGIC, return -1;);
691
692 switch (event) {
693 case QUERY_TIMER_EXPIRED:
694 IRDA_DEBUG(2, "%s(), QUERY_TIMER_EXPIRED <%ld>\n",
695 __FUNCTION__, jiffies);
696 irlap_next_state(self, LAP_NDM);
697 break;
698 case RECV_DISCOVERY_XID_CMD:
699 ASSERT(info != NULL, return -1;);
700 /* Last frame? */
701 if (info->s == 0xff) {
702 del_timer(&self->query_timer);
703
704 /* info->log.condition = REMOTE; */
705
706 /* Always switch state before calling upper layers */
707 irlap_next_state(self, LAP_NDM);
708
709 irlap_discovery_indication(self, info->discovery);
710 } else if ((info->s >= self->slot) && (!self->frame_sent)) {
711 discovery_rsp = irlmp_get_discovery_response();
712 discovery_rsp->data.daddr = info->daddr;
713
714 irlap_send_discovery_xid_frame(self, info->S,
715 self->slot, FALSE,
716 discovery_rsp);
717
718 self->frame_sent = TRUE;
719 irlap_next_state(self, LAP_REPLY);
720 }
721 break;
722 default:
723 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
724 event, irlap_event[event]);
725
726 ret = -1;
727 break;
728 }
729 return ret;
730 }
731
732 /*
733 * Function irlap_state_conn (event, skb, info)
734 *
735 * CONN, we have received a SNRM command and is waiting for the upper
736 * layer to accept or refuse connection
737 *
738 */
739 static int irlap_state_conn(struct irlap_cb *self, IRLAP_EVENT event,
740 struct sk_buff *skb, struct irlap_info *info)
741 {
742 int ret = 0;
743
744 IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[ event]);
745
746 ASSERT(self != NULL, return -1;);
747 ASSERT(self->magic == LAP_MAGIC, return -1;);
748
749 switch (event) {
750 case CONNECT_RESPONSE:
751 skb_pull(skb, sizeof(struct snrm_frame));
752
753 ASSERT(self->netdev != NULL, return -1;);
754
755 irlap_qos_negotiate(self, skb);
756
757 irlap_initiate_connection_state(self);
758
759 /*
760 * Applying the parameters now will make sure we change speed
761 * *after* we have sent the next frame
762 */
763 irlap_apply_connection_parameters(self, FALSE);
764
765 /*
766 * Sending this frame will force a speed change after it has
767 * been sent (i.e. the frame will be sent at 9600).
768 */
769 irlap_send_ua_response_frame(self, &self->qos_rx);
770
771 #if 0
772 /*
773 * We are allowed to send two frames, but this may increase
774 * the connect latency, so lets not do it for now.
775 */
776 /* This is full of good intentions, but doesn't work in
777 * practice.
778 * After sending the first UA response, we switch the
779 * dongle to the negotiated speed, which is usually
780 * different than 9600 kb/s.
781 * From there, there is two solutions :
782 * 1) The other end has received the first UA response :
783 * it will set up the connection, move to state LAP_NRM_P,
784 * and will ignore and drop the second UA response.
785 * Actually, it's even worse : the other side will almost
786 * immediately send a RR that will likely collide with the
787 * UA response (depending on negotiated turnaround).
788 * 2) The other end has not received the first UA response,
789 * will stay at 9600 and will never see the second UA response.
790 * Jean II */
791 irlap_send_ua_response_frame(self, &self->qos_rx);
792 #endif
793
794 /*
795 * The WD-timer could be set to the duration of the P-timer
796 * for this case, but it is recommended to use twice the
797 * value (note 3 IrLAP p. 60).
798 */
799 irlap_start_wd_timer(self, self->wd_timeout);
800 irlap_next_state(self, LAP_NRM_S);
801
802 break;
803 case RECV_DISCOVERY_XID_CMD:
804 IRDA_DEBUG(3, "%s(), event RECV_DISCOVER_XID_CMD!\n",
805 __FUNCTION__);
806 irlap_next_state(self, LAP_NDM);
807
808 break;
809 case DISCONNECT_REQUEST:
810 IRDA_DEBUG(0, "%s(), Disconnect request!\n", __FUNCTION__);
811 irlap_send_dm_frame(self);
812 irlap_next_state( self, LAP_NDM);
813 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
814 break;
815 default:
816 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
817 event, irlap_event[event]);
818
819 ret = -1;
820 break;
821 }
822
823 return ret;
824 }
825
826 /*
827 * Function irlap_state_setup (event, skb, frame)
828 *
829 * SETUP state, The local layer has transmitted a SNRM command frame to
830 * a remote peer layer and is awaiting a reply .
831 *
832 */
833 static int irlap_state_setup(struct irlap_cb *self, IRLAP_EVENT event,
834 struct sk_buff *skb, struct irlap_info *info)
835 {
836 int ret = 0;
837
838 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
839
840 ASSERT(self != NULL, return -1;);
841 ASSERT(self->magic == LAP_MAGIC, return -1;);
842
843 switch (event) {
844 case FINAL_TIMER_EXPIRED:
845 if (self->retry_count < self->N3) {
846 /*
847 * Perform random backoff, Wait a random number of time units, minimum
848 * duration half the time taken to transmitt a SNRM frame, maximum duration
849 * 1.5 times the time taken to transmit a SNRM frame. So this time should
850 * between 15 msecs and 45 msecs.
851 */
852 irlap_start_backoff_timer(self, MSECS_TO_JIFFIES(20 +
853 (jiffies % 30)));
854 } else {
855 /* Always switch state before calling upper layers */
856 irlap_next_state(self, LAP_NDM);
857
858 irlap_disconnect_indication(self, LAP_FOUND_NONE);
859 }
860 break;
861 case BACKOFF_TIMER_EXPIRED:
862 irlap_send_snrm_frame(self, &self->qos_rx);
863 irlap_start_final_timer(self, self->final_timeout);
864 self->retry_count++;
865 break;
866 case RECV_SNRM_CMD:
867 IRDA_DEBUG(4, "%s(), SNRM battle!\n", __FUNCTION__);
868
869 ASSERT(skb != NULL, return 0;);
870 ASSERT(info != NULL, return 0;);
871
872 /*
873 * The device with the largest device address wins the battle
874 * (both have sent a SNRM command!)
875 */
876 if (info &&(info->daddr > self->saddr)) {
877 del_timer(&self->final_timer);
878 irlap_initiate_connection_state(self);
879
880 ASSERT(self->netdev != NULL, return -1;);
881
882 skb_pull(skb, sizeof(struct snrm_frame));
883
884 irlap_qos_negotiate(self, skb);
885
886 /* Send UA frame and then change link settings */
887 irlap_apply_connection_parameters(self, FALSE);
888 irlap_send_ua_response_frame(self, &self->qos_rx);
889
890 irlap_next_state(self, LAP_NRM_S);
891 irlap_connect_confirm(self, skb);
892
893 /*
894 * The WD-timer could be set to the duration of the
895 * P-timer for this case, but it is recommended
896 * to use twice the value (note 3 IrLAP p. 60).
897 */
898 irlap_start_wd_timer(self, self->wd_timeout);
899 } else {
900 /* We just ignore the other device! */
901 irlap_next_state(self, LAP_SETUP);
902 }
903 break;
904 case RECV_UA_RSP:
905 /* Stop F-timer */
906 del_timer(&self->final_timer);
907
908 /* Initiate connection state */
909 irlap_initiate_connection_state(self);
910
911 /* Negotiate connection parameters */
912 ASSERT(skb->len > 10, return -1;);
913
914 skb_pull(skb, sizeof(struct ua_frame));
915
916 ASSERT(self->netdev != NULL, return -1;);
917
918 irlap_qos_negotiate(self, skb);
919
920 /* Set the new link setting *now* (before the rr frame) */
921 irlap_apply_connection_parameters(self, TRUE);
922 self->retry_count = 0;
923
924 /* Wait for turnaround time to give a chance to the other
925 * device to be ready to receive us.
926 * Note : the time to switch speed is typically larger
927 * than the turnaround time, but as we don't have the other
928 * side speed switch time, that's our best guess...
929 * Jean II */
930 irlap_wait_min_turn_around(self, &self->qos_tx);
931
932 /* This frame will actually be sent at the new speed */
933 irlap_send_rr_frame(self, CMD_FRAME);
934
935 irlap_start_final_timer(self, self->final_timeout/2);
936 irlap_next_state(self, LAP_NRM_P);
937
938 irlap_connect_confirm(self, skb);
939 break;
940 case RECV_DM_RSP: /* FALLTHROUGH */
941 case RECV_DISC_CMD:
942 del_timer(&self->final_timer);
943 irlap_next_state(self, LAP_NDM);
944
945 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
946 break;
947 default:
948 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
949 event, irlap_event[event]);
950
951 ret = -1;
952 break;
953 }
954 return ret;
955 }
956
957 /*
958 * Function irlap_state_offline (self, event, skb, info)
959 *
960 * OFFLINE state, not used for now!
961 *
962 */
963 static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
964 struct sk_buff *skb, struct irlap_info *info)
965 {
966 IRDA_DEBUG( 0, "%s(), Unknown event\n", __FUNCTION__);
967
968 return -1;
969 }
970
971 /*
972 * Function irlap_state_xmit_p (self, event, skb, info)
973 *
974 * XMIT, Only the primary station has right to transmit, and we
975 * therefore do not expect to receive any transmissions from other
976 * stations.
977 *
978 */
979 static int irlap_state_xmit_p(struct irlap_cb *self, IRLAP_EVENT event,
980 struct sk_buff *skb, struct irlap_info *info)
981 {
982 int ret = 0;
983
984 switch (event) {
985 case SEND_I_CMD:
986 /*
987 * Only send frame if send-window > 0.
988 */
989 if ((self->window > 0) && (!self->remote_busy)) {
990 int nextfit;
991 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
992 struct sk_buff *skb_next;
993
994 /* With DYNAMIC_WINDOW, we keep the window size
995 * maximum, and adapt on the packets we are sending.
996 * At 115k, we can send only 2 packets of 2048 bytes
997 * in a 500 ms turnaround. Without this option, we
998 * would always limit the window to 2. With this
999 * option, if we send smaller packets, we can send
1000 * up to 7 of them (always depending on QoS).
1001 * Jean II */
1002
1003 /* Look at the next skb. This is safe, as we are
1004 * the only consumer of the Tx queue (if we are not,
1005 * we have other problems) - Jean II */
1006 skb_next = skb_peek(&self->txq);
1007
1008 /* Check if a subsequent skb exist and would fit in
1009 * the current window (with respect to turnaround
1010 * time).
1011 * This allow us to properly mark the current packet
1012 * with the pf bit, to avoid falling back on the
1013 * second test below, and avoid waiting the
1014 * end of the window and sending a extra RR.
1015 * Note : (skb_next != NULL) <=> (skb_queue_len() > 0)
1016 * Jean II */
1017 nextfit = ((skb_next != NULL) &&
1018 ((skb_next->len + skb->len) <=
1019 self->bytes_left));
1020
1021 /*
1022 * The current packet may not fit ! Because of test
1023 * above, this should not happen any more !!!
1024 * Test if we have transmitted more bytes over the
1025 * link than its possible to do with the current
1026 * speed and turn-around-time.
1027 */
1028 if((!nextfit) && (skb->len > self->bytes_left)) {
1029 IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1030 " more bytes!\n", __FUNCTION__);
1031 /* Requeue the skb */
1032 skb_queue_head(&self->txq, skb_get(skb));
1033 /*
1034 * We should switch state to LAP_NRM_P, but
1035 * that is not possible since we must be sure
1036 * that we poll the other side. Since we have
1037 * used up our time, the poll timer should
1038 * trigger anyway now, so we just wait for it
1039 * DB
1040 */
1041 /*
1042 * Sorry, but that's not totally true. If
1043 * we send 2000B packets, we may wait another
1044 * 1000B until our turnaround expire. That's
1045 * why we need to be proactive in avoiding
1046 * coming here. - Jean II
1047 */
1048 return -EPROTO;
1049 }
1050
1051 /* Substract space used by this skb */
1052 self->bytes_left -= skb->len;
1053 #else /* CONFIG_IRDA_DYNAMIC_WINDOW */
1054 /* Window has been adjusted for the max packet
1055 * size, so much simpler... - Jean II */
1056 nextfit = (skb_queue_len(&self->txq) > 0);
1057 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1058 /*
1059 * Send data with poll bit cleared only if window > 1
1060 * and there is more frames after this one to be sent
1061 */
1062 if ((self->window > 1) && (nextfit)) {
1063 /* More packet to send in current window */
1064 irlap_send_data_primary(self, skb);
1065 irlap_next_state(self, LAP_XMIT_P);
1066 } else {
1067 /* Final packet of window */
1068 irlap_send_data_primary_poll(self, skb);
1069 irlap_next_state(self, LAP_NRM_P);
1070
1071 /*
1072 * Make sure state machine does not try to send
1073 * any more frames
1074 */
1075 ret = -EPROTO;
1076 }
1077 #ifdef CONFIG_IRDA_FAST_RR
1078 /* Peer may want to reply immediately */
1079 self->fast_RR = FALSE;
1080 #endif /* CONFIG_IRDA_FAST_RR */
1081 } else {
1082 IRDA_DEBUG(4, "%s(), Unable to send! remote busy?\n",
1083 __FUNCTION__);
1084 skb_queue_head(&self->txq, skb_get(skb));
1085
1086 /*
1087 * The next ret is important, because it tells
1088 * irlap_next_state _not_ to deliver more frames
1089 */
1090 ret = -EPROTO;
1091 }
1092 break;
1093 case POLL_TIMER_EXPIRED:
1094 IRDA_DEBUG(3, "%s(), POLL_TIMER_EXPIRED <%ld>\n",
1095 __FUNCTION__, jiffies);
1096 irlap_send_rr_frame(self, CMD_FRAME);
1097 /* Return to NRM properly - Jean II */
1098 self->window = self->window_size;
1099 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1100 /* Allowed to transmit a maximum number of bytes again. */
1101 self->bytes_left = self->line_capacity;
1102 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1103 irlap_start_final_timer(self, self->final_timeout);
1104 irlap_next_state(self, LAP_NRM_P);
1105 break;
1106 case DISCONNECT_REQUEST:
1107 del_timer(&self->poll_timer);
1108 irlap_wait_min_turn_around(self, &self->qos_tx);
1109 irlap_send_disc_frame(self);
1110 irlap_flush_all_queues(self);
1111 irlap_start_final_timer(self, self->final_timeout);
1112 self->retry_count = 0;
1113 irlap_next_state(self, LAP_PCLOSE);
1114 break;
1115 case DATA_REQUEST:
1116 /* Nothing to do, irlap_do_event() will send the packet
1117 * when we return... - Jean II */
1118 break;
1119 default:
1120 IRDA_DEBUG(0, "%s(), Unknown event %s\n",
1121 __FUNCTION__, irlap_event[event]);
1122
1123 ret = -EINVAL;
1124 break;
1125 }
1126 return ret;
1127 }
1128
1129 /*
1130 * Function irlap_state_pclose (event, skb, info)
1131 *
1132 * PCLOSE state
1133 */
1134 static int irlap_state_pclose(struct irlap_cb *self, IRLAP_EVENT event,
1135 struct sk_buff *skb, struct irlap_info *info)
1136 {
1137 int ret = 0;
1138
1139 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1140
1141 ASSERT(self != NULL, return -1;);
1142 ASSERT(self->magic == LAP_MAGIC, return -1;);
1143
1144 switch (event) {
1145 case RECV_UA_RSP: /* FALLTHROUGH */
1146 case RECV_DM_RSP:
1147 del_timer(&self->final_timer);
1148
1149 /* Set new link parameters */
1150 irlap_apply_default_connection_parameters(self);
1151
1152 /* Always switch state before calling upper layers */
1153 irlap_next_state(self, LAP_NDM);
1154
1155 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
1156 break;
1157 case FINAL_TIMER_EXPIRED:
1158 if (self->retry_count < self->N3) {
1159 irlap_wait_min_turn_around(self, &self->qos_tx);
1160 irlap_send_disc_frame(self);
1161 irlap_start_final_timer(self, self->final_timeout);
1162 self->retry_count++;
1163 /* Keep state */
1164 } else {
1165 irlap_apply_default_connection_parameters(self);
1166
1167 /* Always switch state before calling upper layers */
1168 irlap_next_state(self, LAP_NDM);
1169
1170 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1171 }
1172 break;
1173 default:
1174 IRDA_DEBUG(1, "%s(), Unknown event %d\n", __FUNCTION__, event);
1175
1176 ret = -1;
1177 break;
1178 }
1179 return ret;
1180 }
1181
1182 /*
1183 * Function irlap_state_nrm_p (self, event, skb, info)
1184 *
1185 * NRM_P (Normal Response Mode as Primary), The primary station has given
1186 * permissions to a secondary station to transmit IrLAP resonse frames
1187 * (by sending a frame with the P bit set). The primary station will not
1188 * transmit any frames and is expecting to receive frames only from the
1189 * secondary to which transmission permissions has been given.
1190 */
1191 static int irlap_state_nrm_p(struct irlap_cb *self, IRLAP_EVENT event,
1192 struct sk_buff *skb, struct irlap_info *info)
1193 {
1194 int ret = 0;
1195 int ns_status;
1196 int nr_status;
1197
1198 switch (event) {
1199 case RECV_I_RSP: /* Optimize for the common case */
1200 /* FIXME: must check for remote_busy below */
1201 #ifdef CONFIG_IRDA_FAST_RR
1202 /*
1203 * Reset the fast_RR so we can use the fast RR code with
1204 * full speed the next time since peer may have more frames
1205 * to transmitt
1206 */
1207 self->fast_RR = FALSE;
1208 #endif /* CONFIG_IRDA_FAST_RR */
1209 ASSERT( info != NULL, return -1;);
1210
1211 ns_status = irlap_validate_ns_received(self, info->ns);
1212 nr_status = irlap_validate_nr_received(self, info->nr);
1213
1214 /*
1215 * Check for expected I(nformation) frame
1216 */
1217 if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1218
1219 /* Update Vr (next frame for us to receive) */
1220 self->vr = (self->vr + 1) % 8;
1221
1222 /* Update Nr received, cleanup our retry queue */
1223 irlap_update_nr_received(self, info->nr);
1224
1225 /*
1226 * Got expected NR, so reset the
1227 * retry_count. This is not done by IrLAP spec,
1228 * which is strange!
1229 */
1230 self->retry_count = 0;
1231 self->ack_required = TRUE;
1232
1233 /* poll bit cleared? */
1234 if (!info->pf) {
1235 /* Keep state, do not move this line */
1236 irlap_next_state(self, LAP_NRM_P);
1237
1238 irlap_data_indication(self, skb, FALSE);
1239 } else {
1240 /* No longer waiting for pf */
1241 del_timer(&self->final_timer);
1242
1243 irlap_wait_min_turn_around(self, &self->qos_tx);
1244
1245 /* Call higher layer *before* changing state
1246 * to give them a chance to send data in the
1247 * next LAP frame.
1248 * Jean II */
1249 irlap_data_indication(self, skb, FALSE);
1250
1251 /* XMIT states are the most dangerous state
1252 * to be in, because user requests are
1253 * processed directly and may change state.
1254 * On the other hand, in NDM_P, those
1255 * requests are queued and we will process
1256 * them when we return to irlap_do_event().
1257 * Jean II
1258 */
1259 irlap_next_state(self, LAP_XMIT_P);
1260
1261 /* This is the last frame.
1262 * Make sure it's always called in XMIT state.
1263 * - Jean II */
1264 irlap_start_poll_timer(self, self->poll_timeout);
1265 }
1266 break;
1267
1268 }
1269 /* Unexpected next to send (Ns) */
1270 if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1271 {
1272 if (!info->pf) {
1273 irlap_update_nr_received(self, info->nr);
1274
1275 /*
1276 * Wait until the last frame before doing
1277 * anything
1278 */
1279
1280 /* Keep state */
1281 irlap_next_state(self, LAP_NRM_P);
1282 } else {
1283 IRDA_DEBUG(4,
1284 "%s(), missing or duplicate frame!\n",
1285 __FUNCTION__);
1286
1287 /* Update Nr received */
1288 irlap_update_nr_received(self, info->nr);
1289
1290 irlap_wait_min_turn_around(self, &self->qos_tx);
1291 irlap_send_rr_frame(self, CMD_FRAME);
1292
1293 self->ack_required = FALSE;
1294
1295 irlap_start_final_timer(self, self->final_timeout);
1296 irlap_next_state(self, LAP_NRM_P);
1297 }
1298 break;
1299 }
1300 /*
1301 * Unexpected next to receive (Nr)
1302 */
1303 if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1304 {
1305 if (info->pf) {
1306 self->vr = (self->vr + 1) % 8;
1307
1308 /* Update Nr received */
1309 irlap_update_nr_received(self, info->nr);
1310
1311 /* Resend rejected frames */
1312 irlap_resend_rejected_frames(self, CMD_FRAME);
1313
1314 self->ack_required = FALSE;
1315 irlap_start_final_timer(self, self->final_timeout);
1316
1317 /* Keep state, do not move this line */
1318 irlap_next_state(self, LAP_NRM_P);
1319
1320 irlap_data_indication(self, skb, FALSE);
1321 } else {
1322 /*
1323 * Do not resend frames until the last
1324 * frame has arrived from the other
1325 * device. This is not documented in
1326 * IrLAP!!
1327 */
1328 self->vr = (self->vr + 1) % 8;
1329
1330 /* Update Nr received */
1331 irlap_update_nr_received(self, info->nr);
1332
1333 self->ack_required = FALSE;
1334
1335 /* Keep state, do not move this line!*/
1336 irlap_next_state(self, LAP_NRM_P);
1337
1338 irlap_data_indication(self, skb, FALSE);
1339 }
1340 break;
1341 }
1342 /*
1343 * Unexpected next to send (Ns) and next to receive (Nr)
1344 * Not documented by IrLAP!
1345 */
1346 if ((ns_status == NS_UNEXPECTED) &&
1347 (nr_status == NR_UNEXPECTED))
1348 {
1349 IRDA_DEBUG(4, "%s(), unexpected nr and ns!\n",
1350 __FUNCTION__);
1351 if (info->pf) {
1352 /* Resend rejected frames */
1353 irlap_resend_rejected_frames(self, CMD_FRAME);
1354
1355 /* Give peer some time to retransmit! */
1356 irlap_start_final_timer(self, self->final_timeout);
1357
1358 /* Keep state, do not move this line */
1359 irlap_next_state(self, LAP_NRM_P);
1360 } else {
1361 /* Update Nr received */
1362 /* irlap_update_nr_received( info->nr); */
1363
1364 self->ack_required = FALSE;
1365 }
1366 break;
1367 }
1368
1369 /*
1370 * Invalid NR or NS
1371 */
1372 if ((nr_status == NR_INVALID) || (ns_status == NS_INVALID)) {
1373 if (info->pf) {
1374 del_timer(&self->final_timer);
1375
1376 irlap_next_state(self, LAP_RESET_WAIT);
1377
1378 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1379 self->xmitflag = TRUE;
1380 } else {
1381 del_timer(&self->final_timer);
1382
1383 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1384
1385 self->xmitflag = FALSE;
1386 }
1387 break;
1388 }
1389 IRDA_DEBUG(1, "%s(), Not implemented!\n", __FUNCTION__);
1390 IRDA_DEBUG(1, "%s(), event=%s, ns_status=%d, nr_status=%d\n",
1391 __FUNCTION__, irlap_event[event], ns_status, nr_status);
1392 break;
1393 case RECV_UI_FRAME:
1394 /* Poll bit cleared? */
1395 if (!info->pf) {
1396 irlap_data_indication(self, skb, TRUE);
1397 irlap_next_state(self, LAP_NRM_P);
1398 } else {
1399 del_timer(&self->final_timer);
1400 irlap_data_indication(self, skb, TRUE);
1401 irlap_next_state(self, LAP_XMIT_P);
1402 IRDA_DEBUG(1, "%s: RECV_UI_FRAME: next state %s\n", __FUNCTION__, irlap_state[self->state]);
1403 irlap_start_poll_timer(self, self->poll_timeout);
1404 }
1405 break;
1406 case RECV_RR_RSP:
1407 /*
1408 * If you get a RR, the remote isn't busy anymore,
1409 * no matter what the NR
1410 */
1411 self->remote_busy = FALSE;
1412
1413 /*
1414 * Nr as expected?
1415 */
1416 ret = irlap_validate_nr_received(self, info->nr);
1417 if (ret == NR_EXPECTED) {
1418 /* Stop final timer */
1419 del_timer(&self->final_timer);
1420
1421 /* Update Nr received */
1422 irlap_update_nr_received(self, info->nr);
1423
1424 /*
1425 * Got expected NR, so reset the retry_count. This
1426 * is not done by the IrLAP standard , which is
1427 * strange! DB.
1428 */
1429 self->retry_count = 0;
1430 irlap_wait_min_turn_around(self, &self->qos_tx);
1431
1432 irlap_next_state(self, LAP_XMIT_P);
1433
1434 /* Start poll timer */
1435 irlap_start_poll_timer(self, self->poll_timeout);
1436 } else if (ret == NR_UNEXPECTED) {
1437 ASSERT(info != NULL, return -1;);
1438 /*
1439 * Unexpected nr!
1440 */
1441
1442 /* Update Nr received */
1443 irlap_update_nr_received(self, info->nr);
1444
1445 IRDA_DEBUG(4, "RECV_RR_FRAME: Retrans:%d, nr=%d, va=%d, "
1446 "vs=%d, vr=%d\n",
1447 self->retry_count, info->nr, self->va,
1448 self->vs, self->vr);
1449
1450 /* Resend rejected frames */
1451 irlap_resend_rejected_frames(self, CMD_FRAME);
1452
1453 irlap_next_state(self, LAP_NRM_P);
1454 } else if (ret == NR_INVALID) {
1455 IRDA_DEBUG(1, "%s(), Received RR with "
1456 "invalid nr !\n", __FUNCTION__);
1457 del_timer(&self->final_timer);
1458
1459 irlap_next_state(self, LAP_RESET_WAIT);
1460
1461 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1462 self->xmitflag = TRUE;
1463 }
1464 break;
1465 case RECV_RNR_RSP:
1466 ASSERT(info != NULL, return -1;);
1467
1468 /* Stop final timer */
1469 del_timer(&self->final_timer);
1470 self->remote_busy = TRUE;
1471
1472 /* Update Nr received */
1473 irlap_update_nr_received(self, info->nr);
1474 irlap_next_state(self, LAP_XMIT_P);
1475
1476 /* Start poll timer */
1477 irlap_start_poll_timer(self, self->poll_timeout);
1478 break;
1479 case RECV_FRMR_RSP:
1480 del_timer(&self->final_timer);
1481 self->xmitflag = TRUE;
1482 irlap_next_state(self, LAP_RESET_WAIT);
1483 irlap_reset_indication(self);
1484 break;
1485 case FINAL_TIMER_EXPIRED:
1486 /*
1487 * We are allowed to wait for additional 300 ms if
1488 * final timer expires when we are in the middle
1489 * of receiving a frame (page 45, IrLAP). Check that
1490 * we only do this once for each frame.
1491 */
1492 if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
1493 IRDA_DEBUG(1, "FINAL_TIMER_EXPIRED when receiving a "
1494 "frame! Waiting a little bit more!\n");
1495 irlap_start_final_timer(self, MSECS_TO_JIFFIES(300));
1496
1497 /*
1498 * Don't allow this to happen one more time in a row,
1499 * or else we can get a pretty tight loop here if
1500 * if we only receive half a frame. DB.
1501 */
1502 self->add_wait = TRUE;
1503 break;
1504 }
1505 self->add_wait = FALSE;
1506
1507 /* N2 is the disconnect timer. Until we reach it, we retry */
1508 if (self->retry_count < self->N2) {
1509 /* Retry sending the pf bit to the secondary */
1510 irlap_wait_min_turn_around(self, &self->qos_tx);
1511 irlap_send_rr_frame(self, CMD_FRAME);
1512
1513 irlap_start_final_timer(self, self->final_timeout);
1514 self->retry_count++;
1515 IRDA_DEBUG(4, "irlap_state_nrm_p: FINAL_TIMER_EXPIRED:"
1516 " retry_count=%d\n", self->retry_count);
1517
1518 /* Early warning event. I'm using a pretty liberal
1519 * interpretation of the spec and generate an event
1520 * every time the timer is multiple of N1 (and not
1521 * only the first time). This allow application
1522 * to know precisely if connectivity restart...
1523 * Jean II */
1524 if((self->retry_count % self->N1) == 0)
1525 irlap_status_indication(self,
1526 STATUS_NO_ACTIVITY);
1527
1528 /* Keep state */
1529 } else {
1530 irlap_apply_default_connection_parameters(self);
1531
1532 /* Always switch state before calling upper layers */
1533 irlap_next_state(self, LAP_NDM);
1534 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1535 }
1536 break;
1537 case RECV_REJ_RSP:
1538 irlap_update_nr_received(self, info->nr);
1539 if (self->remote_busy) {
1540 irlap_wait_min_turn_around(self, &self->qos_tx);
1541 irlap_send_rr_frame(self, CMD_FRAME);
1542 } else
1543 irlap_resend_rejected_frames(self, CMD_FRAME);
1544 irlap_start_final_timer(self, self->final_timeout);
1545 break;
1546 case RECV_SREJ_RSP:
1547 irlap_update_nr_received(self, info->nr);
1548 if (self->remote_busy) {
1549 irlap_wait_min_turn_around(self, &self->qos_tx);
1550 irlap_send_rr_frame(self, CMD_FRAME);
1551 } else
1552 irlap_resend_rejected_frame(self, CMD_FRAME);
1553 irlap_start_final_timer(self, self->final_timeout);
1554 break;
1555 case RECV_RD_RSP:
1556 IRDA_DEBUG(1, "%s(), RECV_RD_RSP\n", __FUNCTION__);
1557
1558 irlap_flush_all_queues(self);
1559 irlap_next_state(self, LAP_XMIT_P);
1560 /* Call back the LAP state machine to do a proper disconnect */
1561 irlap_disconnect_request(self);
1562 break;
1563 default:
1564 IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1565 __FUNCTION__, irlap_event[event]);
1566
1567 ret = -1;
1568 break;
1569 }
1570 return ret;
1571 }
1572
1573 /*
1574 * Function irlap_state_reset_wait (event, skb, info)
1575 *
1576 * We have informed the service user of a reset condition, and is
1577 * awaiting reset of disconnect request.
1578 *
1579 */
1580 static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
1581 struct sk_buff *skb, struct irlap_info *info)
1582 {
1583 int ret = 0;
1584
1585 IRDA_DEBUG(3, "%s(), event = %s\n", __FUNCTION__, irlap_event[event]);
1586
1587 ASSERT(self != NULL, return -1;);
1588 ASSERT(self->magic == LAP_MAGIC, return -1;);
1589
1590 switch (event) {
1591 case RESET_REQUEST:
1592 if (self->xmitflag) {
1593 irlap_wait_min_turn_around(self, &self->qos_tx);
1594 irlap_send_snrm_frame(self, NULL);
1595 irlap_start_final_timer(self, self->final_timeout);
1596 irlap_next_state(self, LAP_RESET);
1597 } else {
1598 irlap_start_final_timer(self, self->final_timeout);
1599 irlap_next_state(self, LAP_RESET);
1600 }
1601 break;
1602 case DISCONNECT_REQUEST:
1603 irlap_wait_min_turn_around( self, &self->qos_tx);
1604 irlap_send_disc_frame( self);
1605 irlap_flush_all_queues( self);
1606 irlap_start_final_timer( self, self->final_timeout);
1607 self->retry_count = 0;
1608 irlap_next_state( self, LAP_PCLOSE);
1609 break;
1610 default:
1611 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
1612 irlap_event[event]);
1613
1614 ret = -1;
1615 break;
1616 }
1617 return ret;
1618 }
1619
1620 /*
1621 * Function irlap_state_reset (self, event, skb, info)
1622 *
1623 * We have sent a SNRM reset command to the peer layer, and is awaiting
1624 * reply.
1625 *
1626 */
1627 static int irlap_state_reset(struct irlap_cb *self, IRLAP_EVENT event,
1628 struct sk_buff *skb, struct irlap_info *info)
1629 {
1630 int ret = 0;
1631
1632 IRDA_DEBUG(3, "%s(), event = %s\n", __FUNCTION__, irlap_event[event]);
1633
1634 ASSERT(self != NULL, return -1;);
1635 ASSERT(self->magic == LAP_MAGIC, return -1;);
1636
1637 switch (event) {
1638 case RECV_DISC_CMD:
1639 del_timer(&self->final_timer);
1640
1641 irlap_apply_default_connection_parameters(self);
1642
1643 /* Always switch state before calling upper layers */
1644 irlap_next_state(self, LAP_NDM);
1645
1646 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1647
1648 break;
1649 case RECV_UA_RSP:
1650 del_timer(&self->final_timer);
1651
1652 /* Initiate connection state */
1653 irlap_initiate_connection_state(self);
1654
1655 irlap_reset_confirm();
1656
1657 self->remote_busy = FALSE;
1658
1659 irlap_next_state(self, LAP_XMIT_P);
1660
1661 irlap_start_poll_timer(self, self->poll_timeout);
1662
1663 break;
1664 case FINAL_TIMER_EXPIRED:
1665 if (self->retry_count < 3) {
1666 irlap_wait_min_turn_around(self, &self->qos_tx);
1667
1668 ASSERT(self->netdev != NULL, return -1;);
1669 irlap_send_snrm_frame(self, self->qos_dev);
1670
1671 self->retry_count++; /* Experimental!! */
1672
1673 irlap_start_final_timer(self, self->final_timeout);
1674 irlap_next_state(self, LAP_RESET);
1675 } else if (self->retry_count >= self->N3) {
1676 irlap_apply_default_connection_parameters(self);
1677
1678 /* Always switch state before calling upper layers */
1679 irlap_next_state(self, LAP_NDM);
1680
1681 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1682 }
1683 break;
1684 case RECV_SNRM_CMD:
1685 /*
1686 * SNRM frame is not allowed to contain an I-field in this
1687 * state
1688 */
1689 if (!info) {
1690 IRDA_DEBUG(3, "%s(), RECV_SNRM_CMD\n", __FUNCTION__);
1691 irlap_initiate_connection_state(self);
1692 irlap_wait_min_turn_around(self, &self->qos_tx);
1693 irlap_send_ua_response_frame(self, &self->qos_rx);
1694 irlap_reset_confirm();
1695 irlap_start_wd_timer(self, self->wd_timeout);
1696 irlap_next_state(self, LAP_NDM);
1697 } else {
1698 IRDA_DEBUG(0,
1699 "%s(), SNRM frame contained an I field!\n",
1700 __FUNCTION__);
1701 }
1702 break;
1703 default:
1704 IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1705 __FUNCTION__, irlap_event[event]);
1706
1707 ret = -1;
1708 break;
1709 }
1710 return ret;
1711 }
1712
1713 /*
1714 * Function irlap_state_xmit_s (event, skb, info)
1715 *
1716 * XMIT_S, The secondary station has been given the right to transmit,
1717 * and we therefor do not expect to receive any transmissions from other
1718 * stations.
1719 */
1720 static int irlap_state_xmit_s(struct irlap_cb *self, IRLAP_EVENT event,
1721 struct sk_buff *skb, struct irlap_info *info)
1722 {
1723 int ret = 0;
1724
1725 IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[event]);
1726
1727 ASSERT(self != NULL, return -ENODEV;);
1728 ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
1729
1730 switch (event) {
1731 case SEND_I_CMD:
1732 /*
1733 * Send frame only if send window > 0
1734 */
1735 if ((self->window > 0) && (!self->remote_busy)) {
1736 int nextfit;
1737 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1738 struct sk_buff *skb_next;
1739
1740 /*
1741 * Same deal as in irlap_state_xmit_p(), so see
1742 * the comments at that point.
1743 * We are the secondary, so there are only subtle
1744 * differences. - Jean II
1745 */
1746
1747 /* Check if a subsequent skb exist and would fit in
1748 * the current window (with respect to turnaround
1749 * time). - Jean II */
1750 skb_next = skb_peek(&self->txq);
1751 nextfit = ((skb_next != NULL) &&
1752 ((skb_next->len + skb->len) <=
1753 self->bytes_left));
1754
1755 /*
1756 * Test if we have transmitted more bytes over the
1757 * link than its possible to do with the current
1758 * speed and turn-around-time.
1759 */
1760 if((!nextfit) && (skb->len > self->bytes_left)) {
1761 IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1762 " more bytes!\n", __FUNCTION__);
1763 /* Requeue the skb */
1764 skb_queue_head(&self->txq, skb_get(skb));
1765
1766 /*
1767 * Switch to NRM_S, this is only possible
1768 * when we are in secondary mode, since we
1769 * must be sure that we don't miss any RR
1770 * frames
1771 */
1772 self->window = self->window_size;
1773 self->bytes_left = self->line_capacity;
1774 irlap_start_wd_timer(self, self->wd_timeout);
1775
1776 irlap_next_state(self, LAP_NRM_S);
1777 /* Slight difference with primary :
1778 * here we would wait for the other side to
1779 * expire the turnaround. - Jean II */
1780
1781 return -EPROTO; /* Try again later */
1782 }
1783 /* Substract space used by this skb */
1784 self->bytes_left -= skb->len;
1785 #else /* CONFIG_IRDA_DYNAMIC_WINDOW */
1786 /* Window has been adjusted for the max packet
1787 * size, so much simpler... - Jean II */
1788 nextfit = (skb_queue_len(&self->txq) > 0);
1789 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1790 /*
1791 * Send data with final bit cleared only if window > 1
1792 * and there is more frames to be sent
1793 */
1794 if ((self->window > 1) && (nextfit)) {
1795 irlap_send_data_secondary(self, skb);
1796 irlap_next_state(self, LAP_XMIT_S);
1797 } else {
1798 irlap_send_data_secondary_final(self, skb);
1799 irlap_next_state(self, LAP_NRM_S);
1800
1801 /*
1802 * Make sure state machine does not try to send
1803 * any more frames
1804 */
1805 ret = -EPROTO;
1806 }
1807 } else {
1808 IRDA_DEBUG(2, "%s(), Unable to send!\n", __FUNCTION__);
1809 skb_queue_head(&self->txq, skb_get(skb));
1810 ret = -EPROTO;
1811 }
1812 break;
1813 case DISCONNECT_REQUEST:
1814 irlap_send_rd_frame(self);
1815 irlap_flush_all_queues(self);
1816 irlap_start_wd_timer(self, self->wd_timeout);
1817 irlap_next_state(self, LAP_SCLOSE);
1818 break;
1819 case DATA_REQUEST:
1820 /* Nothing to do, irlap_do_event() will send the packet
1821 * when we return... - Jean II */
1822 break;
1823 default:
1824 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
1825 irlap_event[event]);
1826
1827 ret = -EINVAL;
1828 break;
1829 }
1830 return ret;
1831 }
1832
1833 /*
1834 * Function irlap_state_nrm_s (event, skb, info)
1835 *
1836 * NRM_S (Normal Response Mode as Secondary) state, in this state we are
1837 * expecting to receive frames from the primary station
1838 *
1839 */
1840 static int irlap_state_nrm_s(struct irlap_cb *self, IRLAP_EVENT event,
1841 struct sk_buff *skb, struct irlap_info *info)
1842 {
1843 int ns_status;
1844 int nr_status;
1845 int ret = 0;
1846
1847 IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[ event]);
1848
1849 ASSERT(self != NULL, return -1;);
1850 ASSERT(self->magic == LAP_MAGIC, return -1;);
1851
1852 switch (event) {
1853 case RECV_I_CMD: /* Optimize for the common case */
1854 /* FIXME: must check for remote_busy below */
1855 IRDA_DEBUG(4, "%s(), event=%s nr=%d, vs=%d, ns=%d, "
1856 "vr=%d, pf=%d\n", __FUNCTION__,
1857 irlap_event[event], info->nr,
1858 self->vs, info->ns, self->vr, info->pf);
1859
1860 self->retry_count = 0;
1861
1862 ns_status = irlap_validate_ns_received(self, info->ns);
1863 nr_status = irlap_validate_nr_received(self, info->nr);
1864 /*
1865 * Check for expected I(nformation) frame
1866 */
1867 if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1868
1869 /* Update Vr (next frame for us to receive) */
1870 self->vr = (self->vr + 1) % 8;
1871
1872 /* Update Nr received */
1873 irlap_update_nr_received(self, info->nr);
1874
1875 /*
1876 * poll bit cleared?
1877 */
1878 if (!info->pf) {
1879
1880 self->ack_required = TRUE;
1881
1882 /*
1883 * Starting WD-timer here is optional, but
1884 * not recommended. Note 6 IrLAP p. 83
1885 */
1886 #if 0
1887 irda_start_timer(WD_TIMER, self->wd_timeout);
1888 #endif
1889 /* Keep state, do not move this line */
1890 irlap_next_state(self, LAP_NRM_S);
1891
1892 irlap_data_indication(self, skb, FALSE);
1893 break;
1894 } else {
1895 /*
1896 * We should wait before sending RR, and
1897 * also before changing to XMIT_S
1898 * state. (note 1, IrLAP p. 82)
1899 */
1900 irlap_wait_min_turn_around(self, &self->qos_tx);
1901
1902 /*
1903 * Give higher layers a chance to
1904 * immediately reply with some data before
1905 * we decide if we should send a RR frame
1906 * or not
1907 */
1908 irlap_data_indication(self, skb, FALSE);
1909
1910 /* Any pending data requests? */
1911 if ((skb_queue_len(&self->txq) > 0) &&
1912 (self->window > 0))
1913 {
1914 self->ack_required = TRUE;
1915
1916 del_timer(&self->wd_timer);
1917
1918 irlap_next_state(self, LAP_XMIT_S);
1919 } else {
1920 irlap_send_rr_frame(self, RSP_FRAME);
1921 irlap_start_wd_timer(self,
1922 self->wd_timeout);
1923
1924 /* Keep the state */
1925 irlap_next_state(self, LAP_NRM_S);
1926 }
1927 break;
1928 }
1929 }
1930 /*
1931 * Check for Unexpected next to send (Ns)
1932 */
1933 if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1934 {
1935 /* Unexpected next to send, with final bit cleared */
1936 if (!info->pf) {
1937 irlap_update_nr_received(self, info->nr);
1938
1939 irlap_start_wd_timer(self, self->wd_timeout);
1940 } else {
1941 /* Update Nr received */
1942 irlap_update_nr_received(self, info->nr);
1943
1944 irlap_wait_min_turn_around(self, &self->qos_tx);
1945 irlap_send_rr_frame(self, RSP_FRAME);
1946
1947 irlap_start_wd_timer(self, self->wd_timeout);
1948 }
1949 break;
1950 }
1951
1952 /*
1953 * Unexpected Next to Receive(NR) ?
1954 */
1955 if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1956 {
1957 if (info->pf) {
1958 IRDA_DEBUG(4, "RECV_I_RSP: frame(s) lost\n");
1959
1960 self->vr = (self->vr + 1) % 8;
1961
1962 /* Update Nr received */
1963 irlap_update_nr_received(self, info->nr);
1964
1965 /* Resend rejected frames */
1966 irlap_resend_rejected_frames(self, RSP_FRAME);
1967
1968 /* Keep state, do not move this line */
1969 irlap_next_state(self, LAP_NRM_S);
1970
1971 irlap_data_indication(self, skb, FALSE);
1972 irlap_start_wd_timer(self, self->wd_timeout);
1973 break;
1974 }
1975 /*
1976 * This is not documented in IrLAP!! Unexpected NR
1977 * with poll bit cleared
1978 */
1979 if (!info->pf) {
1980 self->vr = (self->vr + 1) % 8;
1981
1982 /* Update Nr received */
1983 irlap_update_nr_received(self, info->nr);
1984
1985 /* Keep state, do not move this line */
1986 irlap_next_state(self, LAP_NRM_S);
1987
1988 irlap_data_indication(self, skb, FALSE);
1989 irlap_start_wd_timer(self, self->wd_timeout);
1990 }
1991 break;
1992 }
1993
1994 if (ret == NR_INVALID) {
1995 IRDA_DEBUG(0, "NRM_S, NR_INVALID not implemented!\n");
1996 }
1997 if (ret == NS_INVALID) {
1998 IRDA_DEBUG(0, "NRM_S, NS_INVALID not implemented!\n");
1999 }
2000 break;
2001 case RECV_UI_FRAME:
2002 /*
2003 * poll bit cleared?
2004 */
2005 if (!info->pf) {
2006 irlap_data_indication(self, skb, TRUE);
2007 irlap_next_state(self, LAP_NRM_S); /* Keep state */
2008 } else {
2009 /*
2010 * Any pending data requests?
2011 */
2012 if ((skb_queue_len(&self->txq) > 0) &&
2013 (self->window > 0) && !self->remote_busy)
2014 {
2015 irlap_data_indication(self, skb, TRUE);
2016
2017 del_timer(&self->wd_timer);
2018
2019 irlap_next_state(self, LAP_XMIT_S);
2020 } else {
2021 irlap_data_indication(self, skb, TRUE);
2022
2023 irlap_wait_min_turn_around(self, &self->qos_tx);
2024
2025 irlap_send_rr_frame(self, RSP_FRAME);
2026 self->ack_required = FALSE;
2027
2028 irlap_start_wd_timer(self, self->wd_timeout);
2029
2030 /* Keep the state */
2031 irlap_next_state(self, LAP_NRM_S);
2032 }
2033 }
2034 break;
2035 case RECV_RR_CMD:
2036 self->retry_count = 0;
2037
2038 /*
2039 * Nr as expected?
2040 */
2041 nr_status = irlap_validate_nr_received(self, info->nr);
2042 if (nr_status == NR_EXPECTED) {
2043 if ((skb_queue_len( &self->txq) > 0) &&
2044 (self->window > 0)) {
2045 self->remote_busy = FALSE;
2046
2047 /* Update Nr received */
2048 irlap_update_nr_received(self, info->nr);
2049 del_timer(&self->wd_timer);
2050
2051 irlap_wait_min_turn_around(self, &self->qos_tx);
2052 irlap_next_state(self, LAP_XMIT_S);
2053 } else {
2054 self->remote_busy = FALSE;
2055 /* Update Nr received */
2056 irlap_update_nr_received(self, info->nr);
2057 irlap_wait_min_turn_around(self, &self->qos_tx);
2058 irlap_start_wd_timer(self, self->wd_timeout);
2059
2060 /* Note : if the link is idle (this case),
2061 * we never go in XMIT_S, so we never get a
2062 * chance to process any DISCONNECT_REQUEST.
2063 * Do it now ! - Jean II */
2064 if (self->disconnect_pending) {
2065 /* Disconnect */
2066 irlap_send_rd_frame(self);
2067 irlap_flush_all_queues(self);
2068
2069 irlap_next_state(self, LAP_SCLOSE);
2070 } else {
2071 /* Just send back pf bit */
2072 irlap_send_rr_frame(self, RSP_FRAME);
2073
2074 irlap_next_state(self, LAP_NRM_S);
2075 }
2076 }
2077 } else if (nr_status == NR_UNEXPECTED) {
2078 self->remote_busy = FALSE;
2079 irlap_update_nr_received(self, info->nr);
2080 irlap_resend_rejected_frames(self, RSP_FRAME);
2081
2082 irlap_start_wd_timer(self, self->wd_timeout);
2083
2084 /* Keep state */
2085 irlap_next_state(self, LAP_NRM_S);
2086 } else {
2087 IRDA_DEBUG(1, "%s(), invalid nr not implemented!\n",
2088 __FUNCTION__);
2089 }
2090 break;
2091 case RECV_SNRM_CMD:
2092 /* SNRM frame is not allowed to contain an I-field */
2093 if (!info) {
2094 del_timer(&self->wd_timer);
2095 IRDA_DEBUG(1, "%s(), received SNRM cmd\n", __FUNCTION__);
2096 irlap_next_state(self, LAP_RESET_CHECK);
2097
2098 irlap_reset_indication(self);
2099 } else {
2100 IRDA_DEBUG(0,
2101 "%s(), SNRM frame contained an I-field!\n",
2102 __FUNCTION__);
2103
2104 }
2105 break;
2106 case RECV_REJ_CMD:
2107 irlap_update_nr_received(self, info->nr);
2108 if (self->remote_busy) {
2109 irlap_wait_min_turn_around(self, &self->qos_tx);
2110 irlap_send_rr_frame(self, RSP_FRAME);
2111 } else
2112 irlap_resend_rejected_frames(self, RSP_FRAME);
2113 irlap_start_wd_timer(self, self->wd_timeout);
2114 break;
2115 case RECV_SREJ_CMD:
2116 irlap_update_nr_received(self, info->nr);
2117 if (self->remote_busy) {
2118 irlap_wait_min_turn_around(self, &self->qos_tx);
2119 irlap_send_rr_frame(self, RSP_FRAME);
2120 } else
2121 irlap_resend_rejected_frame(self, RSP_FRAME);
2122 irlap_start_wd_timer(self, self->wd_timeout);
2123 break;
2124 case WD_TIMER_EXPIRED:
2125 /*
2126 * Wait until retry_count * n matches negotiated threshold/
2127 * disconnect time (note 2 in IrLAP p. 82)
2128 *
2129 * Similar to irlap_state_nrm_p() -> FINAL_TIMER_EXPIRED
2130 * Note : self->wd_timeout = (self->final_timeout * 2),
2131 * which explain why we use (self->N2 / 2) here !!!
2132 * Jean II
2133 */
2134 IRDA_DEBUG(1, "%s(), retry_count = %d\n", __FUNCTION__,
2135 self->retry_count);
2136
2137 if (self->retry_count < (self->N2 / 2)) {
2138 /* No retry, just wait for primary */
2139 irlap_start_wd_timer(self, self->wd_timeout);
2140 self->retry_count++;
2141
2142 if((self->retry_count % (self->N1 / 2)) == 0)
2143 irlap_status_indication(self,
2144 STATUS_NO_ACTIVITY);
2145 } else {
2146 irlap_apply_default_connection_parameters(self);
2147
2148 /* Always switch state before calling upper layers */
2149 irlap_next_state(self, LAP_NDM);
2150 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
2151 }
2152 break;
2153 case RECV_DISC_CMD:
2154 /* Always switch state before calling upper layers */
2155 irlap_next_state(self, LAP_NDM);
2156
2157 /* Send disconnect response */
2158 irlap_wait_min_turn_around(self, &self->qos_tx);
2159 irlap_send_ua_response_frame(self, NULL);
2160
2161 del_timer(&self->wd_timer);
2162 irlap_flush_all_queues(self);
2163 /* Set default link parameters */
2164 irlap_apply_default_connection_parameters(self);
2165
2166 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2167 break;
2168 case RECV_DISCOVERY_XID_CMD:
2169 irlap_wait_min_turn_around(self, &self->qos_tx);
2170 irlap_send_rr_frame(self, RSP_FRAME);
2171 self->ack_required = TRUE;
2172 irlap_start_wd_timer(self, self->wd_timeout);
2173 irlap_next_state(self, LAP_NRM_S);
2174
2175 break;
2176 case RECV_TEST_CMD:
2177 /* Remove test frame header (only LAP header in NRM) */
2178 skb_pull(skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
2179
2180 irlap_wait_min_turn_around(self, &self->qos_tx);
2181 irlap_start_wd_timer(self, self->wd_timeout);
2182
2183 /* Send response (info will be copied) */
2184 irlap_send_test_frame(self, self->caddr, info->daddr, skb);
2185 break;
2186 default:
2187 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2188 event, irlap_event[event]);
2189
2190 ret = -EINVAL;
2191 break;
2192 }
2193 return ret;
2194 }
2195
2196 /*
2197 * Function irlap_state_sclose (self, event, skb, info)
2198 */
2199 static int irlap_state_sclose(struct irlap_cb *self, IRLAP_EVENT event,
2200 struct sk_buff *skb, struct irlap_info *info)
2201 {
2202 int ret = 0;
2203
2204 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
2205
2206 ASSERT(self != NULL, return -ENODEV;);
2207 ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2208
2209 switch (event) {
2210 case RECV_DISC_CMD:
2211 /* Always switch state before calling upper layers */
2212 irlap_next_state(self, LAP_NDM);
2213
2214 /* Send disconnect response */
2215 irlap_wait_min_turn_around(self, &self->qos_tx);
2216 irlap_send_ua_response_frame(self, NULL);
2217
2218 del_timer(&self->wd_timer);
2219 /* Set default link parameters */
2220 irlap_apply_default_connection_parameters(self);
2221
2222 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2223 break;
2224 case RECV_DM_RSP:
2225 /* Always switch state before calling upper layers */
2226 irlap_next_state(self, LAP_NDM);
2227
2228 del_timer(&self->wd_timer);
2229 irlap_apply_default_connection_parameters(self);
2230
2231 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2232 break;
2233 case WD_TIMER_EXPIRED:
2234 /* Always switch state before calling upper layers */
2235 irlap_next_state(self, LAP_NDM);
2236
2237 irlap_apply_default_connection_parameters(self);
2238
2239 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2240 break;
2241 default:
2242 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2243 event, irlap_event[event]);
2244
2245 ret = -EINVAL;
2246 break;
2247 }
2248
2249 return -1;
2250 }
2251
2252 static int irlap_state_reset_check( struct irlap_cb *self, IRLAP_EVENT event,
2253 struct sk_buff *skb,
2254 struct irlap_info *info)
2255 {
2256 int ret = 0;
2257
2258 IRDA_DEBUG(1, "%s(), event=%s\n", __FUNCTION__, irlap_event[event]);
2259
2260 ASSERT(self != NULL, return -ENODEV;);
2261 ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2262
2263 switch (event) {
2264 case RESET_RESPONSE:
2265 irlap_send_ua_response_frame(self, &self->qos_rx);
2266 irlap_initiate_connection_state(self);
2267 irlap_start_wd_timer(self, WD_TIMEOUT);
2268 irlap_flush_all_queues(self);
2269
2270 irlap_next_state(self, LAP_NRM_S);
2271 break;
2272 case DISCONNECT_REQUEST:
2273 irlap_wait_min_turn_around(self, &self->qos_tx);
2274 irlap_send_rd_frame(self);
2275 irlap_start_wd_timer(self, WD_TIMEOUT);
2276 irlap_next_state(self, LAP_SCLOSE);
2277 break;
2278 default:
2279 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2280 event, irlap_event[event]);
2281
2282 ret = -EINVAL;
2283 break;
2284 }
2285 return ret;
2286 }
2287
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