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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*********************************************************************
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 Tromsø 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
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/string.h>
29#include <linux/kernel.h>
30#include <linux/delay.h>
31#include <linux/skbuff.h>
32
33#include <net/irda/irda.h>
34#include <net/irda/irlap_event.h>
35
36#include <net/irda/timer.h>
37#include <net/irda/irlap.h>
38#include <net/irda/irlap_frame.h>
39#include <net/irda/qos.h>
40#include <net/irda/parameters.h>
41#include <net/irda/irlmp.h> /* irlmp_flow_indication(), ... */
42
43#include <net/irda/irda_device.h>
44
45#ifdef CONFIG_IRDA_FAST_RR
46int sysctl_fast_poll_increase = 50;
47#endif
48
49static int irlap_state_ndm (struct irlap_cb *self, IRLAP_EVENT event,
50 struct sk_buff *skb, struct irlap_info *info);
51static int irlap_state_query (struct irlap_cb *self, IRLAP_EVENT event,
52 struct sk_buff *skb, struct irlap_info *info);
53static int irlap_state_reply (struct irlap_cb *self, IRLAP_EVENT event,
54 struct sk_buff *skb, struct irlap_info *info);
55static int irlap_state_conn (struct irlap_cb *self, IRLAP_EVENT event,
56 struct sk_buff *skb, struct irlap_info *info);
57static int irlap_state_setup (struct irlap_cb *self, IRLAP_EVENT event,
58 struct sk_buff *skb, struct irlap_info *info);
59static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
60 struct sk_buff *skb, struct irlap_info *info);
61static int irlap_state_xmit_p (struct irlap_cb *self, IRLAP_EVENT event,
62 struct sk_buff *skb, struct irlap_info *info);
63static int irlap_state_pclose (struct irlap_cb *self, IRLAP_EVENT event,
64 struct sk_buff *skb, struct irlap_info *info);
65static int irlap_state_nrm_p (struct irlap_cb *self, IRLAP_EVENT event,
66 struct sk_buff *skb, struct irlap_info *info);
67static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
68 struct sk_buff *skb, struct irlap_info *info);
69static int irlap_state_reset (struct irlap_cb *self, IRLAP_EVENT event,
70 struct sk_buff *skb, struct irlap_info *info);
71static int irlap_state_nrm_s (struct irlap_cb *self, IRLAP_EVENT event,
72 struct sk_buff *skb, struct irlap_info *info);
73static int irlap_state_xmit_s (struct irlap_cb *self, IRLAP_EVENT event,
74 struct sk_buff *skb, struct irlap_info *info);
75static int irlap_state_sclose (struct irlap_cb *self, IRLAP_EVENT event,
76 struct sk_buff *skb, struct irlap_info *info);
77static int irlap_state_reset_check(struct irlap_cb *, IRLAP_EVENT event,
78 struct sk_buff *, struct irlap_info *);
79
80#ifdef CONFIG_IRDA_DEBUG
81static const char *irlap_event[] = {
82 "DISCOVERY_REQUEST",
83 "CONNECT_REQUEST",
84 "CONNECT_RESPONSE",
85 "DISCONNECT_REQUEST",
86 "DATA_REQUEST",
87 "RESET_REQUEST",
88 "RESET_RESPONSE",
89 "SEND_I_CMD",
90 "SEND_UI_FRAME",
91 "RECV_DISCOVERY_XID_CMD",
92 "RECV_DISCOVERY_XID_RSP",
93 "RECV_SNRM_CMD",
94 "RECV_TEST_CMD",
95 "RECV_TEST_RSP",
96 "RECV_UA_RSP",
97 "RECV_DM_RSP",
98 "RECV_RD_RSP",
99 "RECV_I_CMD",
100 "RECV_I_RSP",
101 "RECV_UI_FRAME",
102 "RECV_FRMR_RSP",
103 "RECV_RR_CMD",
104 "RECV_RR_RSP",
105 "RECV_RNR_CMD",
106 "RECV_RNR_RSP",
107 "RECV_REJ_CMD",
108 "RECV_REJ_RSP",
109 "RECV_SREJ_CMD",
110 "RECV_SREJ_RSP",
111 "RECV_DISC_CMD",
112 "SLOT_TIMER_EXPIRED",
113 "QUERY_TIMER_EXPIRED",
114 "FINAL_TIMER_EXPIRED",
115 "POLL_TIMER_EXPIRED",
116 "DISCOVERY_TIMER_EXPIRED",
117 "WD_TIMER_EXPIRED",
118 "BACKOFF_TIMER_EXPIRED",
119 "MEDIA_BUSY_TIMER_EXPIRED",
120};
121#endif /* CONFIG_IRDA_DEBUG */
122
123const char *irlap_state[] = {
124 "LAP_NDM",
125 "LAP_QUERY",
126 "LAP_REPLY",
127 "LAP_CONN",
128 "LAP_SETUP",
129 "LAP_OFFLINE",
130 "LAP_XMIT_P",
131 "LAP_PCLOSE",
132 "LAP_NRM_P",
133 "LAP_RESET_WAIT",
134 "LAP_RESET",
135 "LAP_NRM_S",
136 "LAP_XMIT_S",
137 "LAP_SCLOSE",
138 "LAP_RESET_CHECK",
139};
140
141static int (*state[])(struct irlap_cb *self, IRLAP_EVENT event,
142 struct sk_buff *skb, struct irlap_info *info) =
143{
144 irlap_state_ndm,
145 irlap_state_query,
146 irlap_state_reply,
147 irlap_state_conn,
148 irlap_state_setup,
149 irlap_state_offline,
150 irlap_state_xmit_p,
151 irlap_state_pclose,
152 irlap_state_nrm_p,
153 irlap_state_reset_wait,
154 irlap_state_reset,
155 irlap_state_nrm_s,
156 irlap_state_xmit_s,
157 irlap_state_sclose,
158 irlap_state_reset_check,
159};
160
161/*
162 * Function irda_poll_timer_expired (data)
163 *
164 * Poll timer has expired. Normally we must now send a RR frame to the
165 * remote device
166 */
167static void irlap_poll_timer_expired(void *data)
168{
169 struct irlap_cb *self = (struct irlap_cb *) data;
170
171 IRDA_ASSERT(self != NULL, return;);
172 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
173
174 irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
175}
176
177/*
178 * Calculate and set time before we will have to send back the pf bit
179 * to the peer. Use in primary.
180 * Make sure that state is XMIT_P/XMIT_S when calling this function
181 * (and that nobody messed up with the state). - Jean II
182 */
183static void irlap_start_poll_timer(struct irlap_cb *self, int timeout)
184{
185 IRDA_ASSERT(self != NULL, return;);
186 IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
187
188#ifdef CONFIG_IRDA_FAST_RR
189 /*
190 * Send out the RR frames faster if our own transmit queue is empty, or
191 * if the peer is busy. The effect is a much faster conversation
192 */
David S. Millerb03efcf2005-07-08 14:57:23 -0700193 if (skb_queue_empty(&self->txq) || self->remote_busy) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700194 if (self->fast_RR == TRUE) {
195 /*
196 * Assert that the fast poll timer has not reached the
197 * normal poll timer yet
198 */
199 if (self->fast_RR_timeout < timeout) {
200 /*
201 * FIXME: this should be a more configurable
202 * function
203 */
204 self->fast_RR_timeout +=
205 (sysctl_fast_poll_increase * HZ/1000);
206
207 /* Use this fast(er) timeout instead */
208 timeout = self->fast_RR_timeout;
209 }
210 } else {
211 self->fast_RR = TRUE;
212
213 /* Start with just 0 ms */
214 self->fast_RR_timeout = 0;
215 timeout = 0;
216 }
217 } else
218 self->fast_RR = FALSE;
219
220 IRDA_DEBUG(3, "%s(), timeout=%d (%ld)\n", __FUNCTION__, timeout, jiffies);
221#endif /* CONFIG_IRDA_FAST_RR */
222
223 if (timeout == 0)
224 irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
225 else
226 irda_start_timer(&self->poll_timer, timeout, self,
227 irlap_poll_timer_expired);
228}
229
230/*
231 * Function irlap_do_event (event, skb, info)
232 *
233 * Rushes through the state machine without any delay. If state == XMIT
234 * then send queued data frames.
235 */
236void irlap_do_event(struct irlap_cb *self, IRLAP_EVENT event,
237 struct sk_buff *skb, struct irlap_info *info)
238{
239 int ret;
240
241 if (!self || self->magic != LAP_MAGIC)
242 return;
243
244 IRDA_DEBUG(3, "%s(), event = %s, state = %s\n", __FUNCTION__,
245 irlap_event[event], irlap_state[self->state]);
246
247 ret = (*state[self->state])(self, event, skb, info);
248
249 /*
250 * Check if there are any pending events that needs to be executed
251 */
252 switch (self->state) {
253 case LAP_XMIT_P: /* FALLTHROUGH */
254 case LAP_XMIT_S:
255 /*
256 * We just received the pf bit and are at the beginning
257 * of a new LAP transmit window.
258 * Check if there are any queued data frames, and do not
259 * try to disconnect link if we send any data frames, since
260 * that will change the state away form XMIT
261 */
262 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
263 skb_queue_len(&self->txq));
264
David S. Millerb03efcf2005-07-08 14:57:23 -0700265 if (!skb_queue_empty(&self->txq)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 /* Prevent race conditions with irlap_data_request() */
267 self->local_busy = TRUE;
268
269 /* Theory of operation.
270 * We send frames up to when we fill the window or
271 * reach line capacity. Those frames will queue up
272 * in the device queue, and the driver will slowly
273 * send them.
274 * After each frame that we send, we poll the higher
275 * layer for more data. It's the right time to do
276 * that because the link layer need to perform the mtt
277 * and then send the first frame, so we can afford
278 * to send a bit of time in kernel space.
279 * The explicit flow indication allow to minimise
280 * buffers (== lower latency), to avoid higher layer
281 * polling via timers (== less context switches) and
282 * to implement a crude scheduler - Jean II */
283
284 /* Try to send away all queued data frames */
285 while ((skb = skb_dequeue(&self->txq)) != NULL) {
286 /* Send one frame */
287 ret = (*state[self->state])(self, SEND_I_CMD,
288 skb, NULL);
289 /* Drop reference count.
290 * It will be increase as needed in
291 * irlap_send_data_xxx() */
292 kfree_skb(skb);
293
294 /* Poll the higher layers for one more frame */
295 irlmp_flow_indication(self->notify.instance,
296 FLOW_START);
297
298 if (ret == -EPROTO)
299 break; /* Try again later! */
300 }
301 /* Finished transmitting */
302 self->local_busy = FALSE;
303 } else if (self->disconnect_pending) {
304 self->disconnect_pending = FALSE;
305
306 ret = (*state[self->state])(self, DISCONNECT_REQUEST,
307 NULL, NULL);
308 }
309 break;
310/* case LAP_NDM: */
311/* case LAP_CONN: */
312/* case LAP_RESET_WAIT: */
313/* case LAP_RESET_CHECK: */
314 default:
315 break;
316 }
317}
318
319/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 * Function irlap_state_ndm (event, skb, frame)
321 *
322 * NDM (Normal Disconnected Mode) state
323 *
324 */
325static int irlap_state_ndm(struct irlap_cb *self, IRLAP_EVENT event,
326 struct sk_buff *skb, struct irlap_info *info)
327{
328 discovery_t *discovery_rsp;
329 int ret = 0;
330
331 IRDA_ASSERT(self != NULL, return -1;);
332 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
333
334 switch (event) {
335 case CONNECT_REQUEST:
336 IRDA_ASSERT(self->netdev != NULL, return -1;);
337
338 if (self->media_busy) {
339 /* Note : this will never happen, because we test
340 * media busy in irlap_connect_request() and
341 * postpone the event... - Jean II */
342 IRDA_DEBUG(0, "%s(), CONNECT_REQUEST: media busy!\n",
343 __FUNCTION__);
344
345 /* Always switch state before calling upper layers */
346 irlap_next_state(self, LAP_NDM);
347
348 irlap_disconnect_indication(self, LAP_MEDIA_BUSY);
349 } else {
350 irlap_send_snrm_frame(self, &self->qos_rx);
351
352 /* Start Final-bit timer */
353 irlap_start_final_timer(self, self->final_timeout);
354
355 self->retry_count = 0;
356 irlap_next_state(self, LAP_SETUP);
357 }
358 break;
359 case RECV_SNRM_CMD:
360 /* Check if the frame contains and I field */
361 if (info) {
362 self->daddr = info->daddr;
363 self->caddr = info->caddr;
364
365 irlap_next_state(self, LAP_CONN);
366
367 irlap_connect_indication(self, skb);
368 } else {
369 IRDA_DEBUG(0, "%s(), SNRM frame does not "
370 "contain an I field!\n", __FUNCTION__);
371 }
372 break;
373 case DISCOVERY_REQUEST:
374 IRDA_ASSERT(info != NULL, return -1;);
375
376 if (self->media_busy) {
377 IRDA_DEBUG(1, "%s(), DISCOVERY_REQUEST: media busy!\n",
378 __FUNCTION__);
379 /* irlap->log.condition = MEDIA_BUSY; */
380
381 /* This will make IrLMP try again */
382 irlap_discovery_confirm(self, NULL);
383 /* Note : the discovery log is not cleaned up here,
384 * it will be done in irlap_discovery_request()
385 * Jean II */
386 return 0;
387 }
388
389 self->S = info->S;
390 self->s = info->s;
391 irlap_send_discovery_xid_frame(self, info->S, info->s, TRUE,
392 info->discovery);
393 self->frame_sent = FALSE;
394 self->s++;
395
396 irlap_start_slot_timer(self, self->slot_timeout);
397 irlap_next_state(self, LAP_QUERY);
398 break;
399 case RECV_DISCOVERY_XID_CMD:
400 IRDA_ASSERT(info != NULL, return -1;);
401
402 /* Assert that this is not the final slot */
403 if (info->s <= info->S) {
404 self->slot = irlap_generate_rand_time_slot(info->S,
405 info->s);
406 if (self->slot == info->s) {
407 discovery_rsp = irlmp_get_discovery_response();
408 discovery_rsp->data.daddr = info->daddr;
409
410 irlap_send_discovery_xid_frame(self, info->S,
411 self->slot,
412 FALSE,
413 discovery_rsp);
414 self->frame_sent = TRUE;
415 } else
416 self->frame_sent = FALSE;
417
418 /*
419 * Go to reply state until end of discovery to
420 * inhibit our own transmissions. Set the timer
421 * to not stay forever there... Jean II
422 */
423 irlap_start_query_timer(self, info->S, info->s);
424 irlap_next_state(self, LAP_REPLY);
425 } else {
426 /* This is the final slot. How is it possible ?
427 * This would happen is both discoveries are just slightly
428 * offset (if they are in sync, all packets are lost).
429 * Most often, all the discovery requests will be received
430 * in QUERY state (see my comment there), except for the
431 * last frame that will come here.
432 * The big trouble when it happen is that active discovery
433 * doesn't happen, because nobody answer the discoveries
434 * frame of the other guy, so the log shows up empty.
435 * What should we do ?
436 * Not much. It's too late to answer those discovery frames,
437 * so we just pass the info to IrLMP who will put it in the
438 * log (and post an event).
439 * Another cause would be devices that do discovery much
440 * slower than us, however the latest fixes should minimise
441 * those cases...
442 * Jean II
443 */
444 IRDA_DEBUG(1, "%s(), Receiving final discovery request, missed the discovery slots :-(\n", __FUNCTION__);
445
446 /* Last discovery request -> in the log */
447 irlap_discovery_indication(self, info->discovery);
448 }
449 break;
450 case MEDIA_BUSY_TIMER_EXPIRED:
451 /* A bunch of events may be postponed because the media is
452 * busy (usually immediately after we close a connection),
453 * or while we are doing discovery (state query/reply).
454 * In all those cases, the media busy flag will be cleared
455 * when it's OK for us to process those postponed events.
456 * This event is not mentioned in the state machines in the
457 * IrLAP spec. It's because they didn't consider Ultra and
458 * postponing connection request is optional.
459 * Jean II */
460#ifdef CONFIG_IRDA_ULTRA
461 /* Send any pending Ultra frames if any */
462 if (!skb_queue_empty(&self->txq_ultra)) {
463 /* We don't send the frame, just post an event.
464 * Also, previously this code was in timer.c...
465 * Jean II */
466 ret = (*state[self->state])(self, SEND_UI_FRAME,
467 NULL, NULL);
468 }
469#endif /* CONFIG_IRDA_ULTRA */
470 /* Check if we should try to connect.
471 * This code was previously in irlap_do_event() */
472 if (self->connect_pending) {
473 self->connect_pending = FALSE;
474
475 /* This one *should* not pend in this state, except
476 * if a socket try to connect and immediately
477 * disconnect. - clear - Jean II */
478 if (self->disconnect_pending)
479 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
480 else
481 ret = (*state[self->state])(self,
482 CONNECT_REQUEST,
483 NULL, NULL);
484 self->disconnect_pending = FALSE;
485 }
486 /* Note : one way to test if this code works well (including
487 * media busy and small busy) is to create a user space
488 * application generating an Ultra packet every 3.05 sec (or
489 * 2.95 sec) and to see how it interact with discovery.
490 * It's fairly easy to check that no packet is lost, that the
491 * packets are postponed during discovery and that after
492 * discovery indication you have a 100ms "gap".
493 * As connection request and Ultra are now processed the same
494 * way, this avoid the tedious job of trying IrLAP connection
495 * in all those cases...
496 * Jean II */
497 break;
498#ifdef CONFIG_IRDA_ULTRA
499 case SEND_UI_FRAME:
500 {
501 int i;
502 /* Only allowed to repeat an operation twice */
503 for (i=0; ((i<2) && (self->media_busy == FALSE)); i++) {
504 skb = skb_dequeue(&self->txq_ultra);
505 if (skb)
506 irlap_send_ui_frame(self, skb, CBROADCAST,
507 CMD_FRAME);
508 else
509 break;
510 /* irlap_send_ui_frame() won't increase skb reference
511 * count, so no dev_kfree_skb() - Jean II */
512 }
513 if (i == 2) {
514 /* Force us to listen 500 ms again */
515 irda_device_set_media_busy(self->netdev, TRUE);
516 }
517 break;
518 }
519 case RECV_UI_FRAME:
520 /* Only accept broadcast frames in NDM mode */
521 if (info->caddr != CBROADCAST) {
522 IRDA_DEBUG(0, "%s(), not a broadcast frame!\n",
523 __FUNCTION__);
524 } else
525 irlap_unitdata_indication(self, skb);
526 break;
527#endif /* CONFIG_IRDA_ULTRA */
528 case RECV_TEST_CMD:
529 /* Remove test frame header */
530 skb_pull(skb, sizeof(struct test_frame));
531
532 /*
533 * Send response. This skb will not be sent out again, and
534 * will only be used to send out the same info as the cmd
535 */
536 irlap_send_test_frame(self, CBROADCAST, info->daddr, skb);
537 break;
538 case RECV_TEST_RSP:
539 IRDA_DEBUG(0, "%s() not implemented!\n", __FUNCTION__);
540 break;
541 default:
542 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
543 irlap_event[event]);
544
545 ret = -1;
546 break;
547 }
548 return ret;
549}
550
551/*
552 * Function irlap_state_query (event, skb, info)
553 *
554 * QUERY state
555 *
556 */
557static int irlap_state_query(struct irlap_cb *self, IRLAP_EVENT event,
558 struct sk_buff *skb, struct irlap_info *info)
559{
560 int ret = 0;
561
562 IRDA_ASSERT(self != NULL, return -1;);
563 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
564
565 switch (event) {
566 case RECV_DISCOVERY_XID_RSP:
567 IRDA_ASSERT(info != NULL, return -1;);
568 IRDA_ASSERT(info->discovery != NULL, return -1;);
569
570 IRDA_DEBUG(4, "%s(), daddr=%08x\n", __FUNCTION__,
571 info->discovery->data.daddr);
572
573 if (!self->discovery_log) {
574 IRDA_WARNING("%s: discovery log is gone! "
575 "maybe the discovery timeout has been set"
G. Liakhovetskib450777a2007-04-20 22:12:48 -0700576 " too short?\n", __FUNCTION__);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 break;
578 }
579 hashbin_insert(self->discovery_log,
580 (irda_queue_t *) info->discovery,
581 info->discovery->data.daddr, NULL);
582
583 /* Keep state */
584 /* irlap_next_state(self, LAP_QUERY); */
585
586 break;
587 case RECV_DISCOVERY_XID_CMD:
588 /* Yes, it is possible to receive those frames in this mode.
589 * Note that most often the last discovery request won't
590 * occur here but in NDM state (see my comment there).
591 * What should we do ?
592 * Not much. We are currently performing our own discovery,
593 * therefore we can't answer those frames. We don't want
594 * to change state either. We just pass the info to
595 * IrLMP who will put it in the log (and post an event).
596 * Jean II
597 */
598
599 IRDA_ASSERT(info != NULL, return -1;);
600
601 IRDA_DEBUG(1, "%s(), Receiving discovery request (s = %d) while performing discovery :-(\n", __FUNCTION__, info->s);
602
603 /* Last discovery request ? */
604 if (info->s == 0xff)
605 irlap_discovery_indication(self, info->discovery);
606 break;
607 case SLOT_TIMER_EXPIRED:
608 /*
609 * Wait a little longer if we detect an incoming frame. This
610 * is not mentioned in the spec, but is a good thing to do,
611 * since we want to work even with devices that violate the
612 * timing requirements.
613 */
614 if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
615 IRDA_DEBUG(2, "%s(), device is slow to answer, "
616 "waiting some more!\n", __FUNCTION__);
617 irlap_start_slot_timer(self, msecs_to_jiffies(10));
618 self->add_wait = TRUE;
619 return ret;
620 }
621 self->add_wait = FALSE;
622
623 if (self->s < self->S) {
624 irlap_send_discovery_xid_frame(self, self->S,
625 self->s, TRUE,
626 self->discovery_cmd);
627 self->s++;
628 irlap_start_slot_timer(self, self->slot_timeout);
629
630 /* Keep state */
631 irlap_next_state(self, LAP_QUERY);
632 } else {
633 /* This is the final slot! */
634 irlap_send_discovery_xid_frame(self, self->S, 0xff,
635 TRUE,
636 self->discovery_cmd);
637
638 /* Always switch state before calling upper layers */
639 irlap_next_state(self, LAP_NDM);
640
641 /*
642 * We are now finished with the discovery procedure,
643 * so now we must return the results
644 */
645 irlap_discovery_confirm(self, self->discovery_log);
646
647 /* IrLMP should now have taken care of the log */
648 self->discovery_log = NULL;
649 }
650 break;
651 default:
652 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
653 irlap_event[event]);
654
655 ret = -1;
656 break;
657 }
658 return ret;
659}
660
661/*
662 * Function irlap_state_reply (self, event, skb, info)
663 *
664 * REPLY, we have received a XID discovery frame from a device and we
665 * are waiting for the right time slot to send a response XID frame
666 *
667 */
668static int irlap_state_reply(struct irlap_cb *self, IRLAP_EVENT event,
669 struct sk_buff *skb, struct irlap_info *info)
670{
671 discovery_t *discovery_rsp;
672 int ret=0;
673
674 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
675
676 IRDA_ASSERT(self != NULL, return -1;);
677 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
678
679 switch (event) {
680 case QUERY_TIMER_EXPIRED:
681 IRDA_DEBUG(0, "%s(), QUERY_TIMER_EXPIRED <%ld>\n",
682 __FUNCTION__, jiffies);
683 irlap_next_state(self, LAP_NDM);
684 break;
685 case RECV_DISCOVERY_XID_CMD:
686 IRDA_ASSERT(info != NULL, return -1;);
687 /* Last frame? */
688 if (info->s == 0xff) {
689 del_timer(&self->query_timer);
690
691 /* info->log.condition = REMOTE; */
692
693 /* Always switch state before calling upper layers */
694 irlap_next_state(self, LAP_NDM);
695
696 irlap_discovery_indication(self, info->discovery);
697 } else {
698 /* If it's our slot, send our reply */
699 if ((info->s >= self->slot) && (!self->frame_sent)) {
700 discovery_rsp = irlmp_get_discovery_response();
701 discovery_rsp->data.daddr = info->daddr;
702
703 irlap_send_discovery_xid_frame(self, info->S,
704 self->slot,
705 FALSE,
706 discovery_rsp);
707
708 self->frame_sent = TRUE;
709 }
710 /* Readjust our timer to accomodate devices
711 * doing faster or slower discovery than us...
712 * Jean II */
713 irlap_start_query_timer(self, info->S, info->s);
714
715 /* Keep state */
716 //irlap_next_state(self, LAP_REPLY);
717 }
718 break;
719 default:
720 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
721 event, irlap_event[event]);
722
723 ret = -1;
724 break;
725 }
726 return ret;
727}
728
729/*
730 * Function irlap_state_conn (event, skb, info)
731 *
732 * CONN, we have received a SNRM command and is waiting for the upper
733 * layer to accept or refuse connection
734 *
735 */
736static int irlap_state_conn(struct irlap_cb *self, IRLAP_EVENT event,
737 struct sk_buff *skb, struct irlap_info *info)
738{
739 int ret = 0;
740
741 IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[ event]);
742
743 IRDA_ASSERT(self != NULL, return -1;);
744 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
745
746 switch (event) {
747 case CONNECT_RESPONSE:
748 skb_pull(skb, sizeof(struct snrm_frame));
749
750 IRDA_ASSERT(self->netdev != NULL, return -1;);
751
752 irlap_qos_negotiate(self, skb);
753
754 irlap_initiate_connection_state(self);
755
756 /*
757 * Applying the parameters now will make sure we change speed
758 * *after* we have sent the next frame
759 */
760 irlap_apply_connection_parameters(self, FALSE);
761
762 /*
763 * Sending this frame will force a speed change after it has
764 * been sent (i.e. the frame will be sent at 9600).
765 */
766 irlap_send_ua_response_frame(self, &self->qos_rx);
767
768#if 0
769 /*
770 * We are allowed to send two frames, but this may increase
771 * the connect latency, so lets not do it for now.
772 */
773 /* This is full of good intentions, but doesn't work in
774 * practice.
775 * After sending the first UA response, we switch the
776 * dongle to the negotiated speed, which is usually
777 * different than 9600 kb/s.
778 * From there, there is two solutions :
779 * 1) The other end has received the first UA response :
780 * it will set up the connection, move to state LAP_NRM_P,
781 * and will ignore and drop the second UA response.
782 * Actually, it's even worse : the other side will almost
783 * immediately send a RR that will likely collide with the
784 * UA response (depending on negotiated turnaround).
785 * 2) The other end has not received the first UA response,
786 * will stay at 9600 and will never see the second UA response.
787 * Jean II */
788 irlap_send_ua_response_frame(self, &self->qos_rx);
789#endif
790
791 /*
792 * The WD-timer could be set to the duration of the P-timer
793 * for this case, but it is recommended to use twice the
794 * value (note 3 IrLAP p. 60).
795 */
796 irlap_start_wd_timer(self, self->wd_timeout);
797 irlap_next_state(self, LAP_NRM_S);
798
799 break;
800 case RECV_DISCOVERY_XID_CMD:
801 IRDA_DEBUG(3, "%s(), event RECV_DISCOVER_XID_CMD!\n",
802 __FUNCTION__);
803 irlap_next_state(self, LAP_NDM);
804
805 break;
806 case DISCONNECT_REQUEST:
807 IRDA_DEBUG(0, "%s(), Disconnect request!\n", __FUNCTION__);
808 irlap_send_dm_frame(self);
809 irlap_next_state( self, LAP_NDM);
810 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
811 break;
812 default:
YOSHIFUJI Hideaki6819bc22007-02-09 23:24:53 +0900813 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700814 event, irlap_event[event]);
815
816 ret = -1;
817 break;
818 }
819
820 return ret;
821}
822
823/*
824 * Function irlap_state_setup (event, skb, frame)
825 *
826 * SETUP state, The local layer has transmitted a SNRM command frame to
827 * a remote peer layer and is awaiting a reply .
828 *
829 */
830static int irlap_state_setup(struct irlap_cb *self, IRLAP_EVENT event,
831 struct sk_buff *skb, struct irlap_info *info)
832{
833 int ret = 0;
834
835 IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
836
837 IRDA_ASSERT(self != NULL, return -1;);
838 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
839
840 switch (event) {
841 case FINAL_TIMER_EXPIRED:
842 if (self->retry_count < self->N3) {
843/*
844 * Perform random backoff, Wait a random number of time units, minimum
845 * duration half the time taken to transmitt a SNRM frame, maximum duration
846 * 1.5 times the time taken to transmit a SNRM frame. So this time should
847 * between 15 msecs and 45 msecs.
848 */
849 irlap_start_backoff_timer(self, msecs_to_jiffies(20 +
YOSHIFUJI Hideaki6819bc22007-02-09 23:24:53 +0900850 (jiffies % 30)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700851 } else {
852 /* Always switch state before calling upper layers */
853 irlap_next_state(self, LAP_NDM);
854
855 irlap_disconnect_indication(self, LAP_FOUND_NONE);
856 }
857 break;
858 case BACKOFF_TIMER_EXPIRED:
859 irlap_send_snrm_frame(self, &self->qos_rx);
860 irlap_start_final_timer(self, self->final_timeout);
861 self->retry_count++;
862 break;
863 case RECV_SNRM_CMD:
864 IRDA_DEBUG(4, "%s(), SNRM battle!\n", __FUNCTION__);
865
866 IRDA_ASSERT(skb != NULL, return 0;);
867 IRDA_ASSERT(info != NULL, return 0;);
868
869 /*
870 * The device with the largest device address wins the battle
871 * (both have sent a SNRM command!)
872 */
873 if (info &&(info->daddr > self->saddr)) {
874 del_timer(&self->final_timer);
875 irlap_initiate_connection_state(self);
876
877 IRDA_ASSERT(self->netdev != NULL, return -1;);
878
879 skb_pull(skb, sizeof(struct snrm_frame));
880
881 irlap_qos_negotiate(self, skb);
882
883 /* Send UA frame and then change link settings */
884 irlap_apply_connection_parameters(self, FALSE);
885 irlap_send_ua_response_frame(self, &self->qos_rx);
886
887 irlap_next_state(self, LAP_NRM_S);
888 irlap_connect_confirm(self, skb);
889
890 /*
891 * The WD-timer could be set to the duration of the
892 * P-timer for this case, but it is recommended
893 * to use twice the value (note 3 IrLAP p. 60).
894 */
895 irlap_start_wd_timer(self, self->wd_timeout);
896 } else {
897 /* We just ignore the other device! */
898 irlap_next_state(self, LAP_SETUP);
899 }
900 break;
901 case RECV_UA_RSP:
902 /* Stop F-timer */
903 del_timer(&self->final_timer);
904
905 /* Initiate connection state */
906 irlap_initiate_connection_state(self);
907
908 /* Negotiate connection parameters */
909 IRDA_ASSERT(skb->len > 10, return -1;);
910
911 skb_pull(skb, sizeof(struct ua_frame));
912
913 IRDA_ASSERT(self->netdev != NULL, return -1;);
914
915 irlap_qos_negotiate(self, skb);
916
917 /* Set the new link setting *now* (before the rr frame) */
918 irlap_apply_connection_parameters(self, TRUE);
919 self->retry_count = 0;
920
921 /* Wait for turnaround time to give a chance to the other
922 * device to be ready to receive us.
923 * Note : the time to switch speed is typically larger
924 * than the turnaround time, but as we don't have the other
925 * side speed switch time, that's our best guess...
926 * Jean II */
927 irlap_wait_min_turn_around(self, &self->qos_tx);
928
929 /* This frame will actually be sent at the new speed */
930 irlap_send_rr_frame(self, CMD_FRAME);
931
932 /* The timer is set to half the normal timer to quickly
933 * detect a failure to negociate the new connection
934 * parameters. IrLAP 6.11.3.2, note 3.
935 * Note that currently we don't process this failure
936 * properly, as we should do a quick disconnect.
937 * Jean II */
938 irlap_start_final_timer(self, self->final_timeout/2);
939 irlap_next_state(self, LAP_NRM_P);
940
941 irlap_connect_confirm(self, skb);
942 break;
943 case RECV_DM_RSP: /* FALLTHROUGH */
944 case RECV_DISC_CMD:
945 del_timer(&self->final_timer);
946 irlap_next_state(self, LAP_NDM);
947
948 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
949 break;
950 default:
951 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
952 event, irlap_event[event]);
953
954 ret = -1;
955 break;
956 }
957 return ret;
958}
959
960/*
961 * Function irlap_state_offline (self, event, skb, info)
962 *
963 * OFFLINE state, not used for now!
964 *
965 */
966static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
967 struct sk_buff *skb, struct irlap_info *info)
968{
969 IRDA_DEBUG( 0, "%s(), Unknown event\n", __FUNCTION__);
970
971 return -1;
972}
973
974/*
975 * Function irlap_state_xmit_p (self, event, skb, info)
976 *
977 * XMIT, Only the primary station has right to transmit, and we
978 * therefore do not expect to receive any transmissions from other
979 * stations.
980 *
981 */
982static int irlap_state_xmit_p(struct irlap_cb *self, IRLAP_EVENT event,
983 struct sk_buff *skb, struct irlap_info *info)
984{
985 int ret = 0;
986
987 switch (event) {
988 case SEND_I_CMD:
989 /*
990 * Only send frame if send-window > 0.
991 */
992 if ((self->window > 0) && (!self->remote_busy)) {
993 int nextfit;
994#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
995 struct sk_buff *skb_next;
996
997 /* With DYNAMIC_WINDOW, we keep the window size
998 * maximum, and adapt on the packets we are sending.
999 * At 115k, we can send only 2 packets of 2048 bytes
1000 * in a 500 ms turnaround. Without this option, we
1001 * would always limit the window to 2. With this
1002 * option, if we send smaller packets, we can send
1003 * up to 7 of them (always depending on QoS).
1004 * Jean II */
1005
1006 /* Look at the next skb. This is safe, as we are
1007 * the only consumer of the Tx queue (if we are not,
1008 * we have other problems) - Jean II */
1009 skb_next = skb_peek(&self->txq);
1010
1011 /* Check if a subsequent skb exist and would fit in
1012 * the current window (with respect to turnaround
1013 * time).
1014 * This allow us to properly mark the current packet
1015 * with the pf bit, to avoid falling back on the
1016 * second test below, and avoid waiting the
1017 * end of the window and sending a extra RR.
1018 * Note : (skb_next != NULL) <=> (skb_queue_len() > 0)
1019 * Jean II */
1020 nextfit = ((skb_next != NULL) &&
1021 ((skb_next->len + skb->len) <=
1022 self->bytes_left));
1023
1024 /*
1025 * The current packet may not fit ! Because of test
1026 * above, this should not happen any more !!!
1027 * Test if we have transmitted more bytes over the
1028 * link than its possible to do with the current
1029 * speed and turn-around-time.
1030 */
1031 if((!nextfit) && (skb->len > self->bytes_left)) {
1032 IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1033 " more bytes!\n", __FUNCTION__);
1034 /* Requeue the skb */
1035 skb_queue_head(&self->txq, skb_get(skb));
1036 /*
1037 * We should switch state to LAP_NRM_P, but
1038 * that is not possible since we must be sure
1039 * that we poll the other side. Since we have
1040 * used up our time, the poll timer should
1041 * trigger anyway now, so we just wait for it
1042 * DB
1043 */
1044 /*
1045 * Sorry, but that's not totally true. If
1046 * we send 2000B packets, we may wait another
1047 * 1000B until our turnaround expire. That's
1048 * why we need to be proactive in avoiding
1049 * coming here. - Jean II
1050 */
1051 return -EPROTO;
1052 }
1053
1054 /* Substract space used by this skb */
1055 self->bytes_left -= skb->len;
1056#else /* CONFIG_IRDA_DYNAMIC_WINDOW */
1057 /* Window has been adjusted for the max packet
1058 * size, so much simpler... - Jean II */
David S. Millerb03efcf2005-07-08 14:57:23 -07001059 nextfit = !skb_queue_empty(&self->txq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1061 /*
1062 * Send data with poll bit cleared only if window > 1
1063 * and there is more frames after this one to be sent
1064 */
1065 if ((self->window > 1) && (nextfit)) {
1066 /* More packet to send in current window */
1067 irlap_send_data_primary(self, skb);
1068 irlap_next_state(self, LAP_XMIT_P);
1069 } else {
1070 /* Final packet of window */
1071 irlap_send_data_primary_poll(self, skb);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001072
1073 /*
1074 * Make sure state machine does not try to send
1075 * any more frames
1076 */
1077 ret = -EPROTO;
1078 }
1079#ifdef CONFIG_IRDA_FAST_RR
1080 /* Peer may want to reply immediately */
1081 self->fast_RR = FALSE;
1082#endif /* CONFIG_IRDA_FAST_RR */
1083 } else {
1084 IRDA_DEBUG(4, "%s(), Unable to send! remote busy?\n",
1085 __FUNCTION__);
1086 skb_queue_head(&self->txq, skb_get(skb));
1087
1088 /*
1089 * The next ret is important, because it tells
1090 * irlap_next_state _not_ to deliver more frames
1091 */
1092 ret = -EPROTO;
1093 }
1094 break;
1095 case POLL_TIMER_EXPIRED:
1096 IRDA_DEBUG(3, "%s(), POLL_TIMER_EXPIRED <%ld>\n",
1097 __FUNCTION__, jiffies);
1098 irlap_send_rr_frame(self, CMD_FRAME);
1099 /* Return to NRM properly - Jean II */
1100 self->window = self->window_size;
1101#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1102 /* Allowed to transmit a maximum number of bytes again. */
1103 self->bytes_left = self->line_capacity;
1104#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1105 irlap_start_final_timer(self, self->final_timeout);
1106 irlap_next_state(self, LAP_NRM_P);
1107 break;
1108 case DISCONNECT_REQUEST:
1109 del_timer(&self->poll_timer);
1110 irlap_wait_min_turn_around(self, &self->qos_tx);
1111 irlap_send_disc_frame(self);
1112 irlap_flush_all_queues(self);
1113 irlap_start_final_timer(self, self->final_timeout);
1114 self->retry_count = 0;
1115 irlap_next_state(self, LAP_PCLOSE);
1116 break;
1117 case DATA_REQUEST:
1118 /* Nothing to do, irlap_do_event() will send the packet
1119 * when we return... - Jean II */
1120 break;
1121 default:
1122 IRDA_DEBUG(0, "%s(), Unknown event %s\n",
1123 __FUNCTION__, irlap_event[event]);
1124
1125 ret = -EINVAL;
1126 break;
1127 }
1128 return ret;
1129}
1130
1131/*
1132 * Function irlap_state_pclose (event, skb, info)
1133 *
1134 * PCLOSE state
1135 */
1136static int irlap_state_pclose(struct irlap_cb *self, IRLAP_EVENT event,
1137 struct sk_buff *skb, struct irlap_info *info)
1138{
1139 int ret = 0;
1140
1141 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1142
1143 IRDA_ASSERT(self != NULL, return -1;);
1144 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1145
1146 switch (event) {
1147 case RECV_UA_RSP: /* FALLTHROUGH */
1148 case RECV_DM_RSP:
1149 del_timer(&self->final_timer);
1150
1151 /* Set new link parameters */
1152 irlap_apply_default_connection_parameters(self);
1153
1154 /* Always switch state before calling upper layers */
1155 irlap_next_state(self, LAP_NDM);
1156
1157 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
1158 break;
1159 case FINAL_TIMER_EXPIRED:
1160 if (self->retry_count < self->N3) {
1161 irlap_wait_min_turn_around(self, &self->qos_tx);
1162 irlap_send_disc_frame(self);
1163 irlap_start_final_timer(self, self->final_timeout);
1164 self->retry_count++;
1165 /* Keep state */
1166 } else {
1167 irlap_apply_default_connection_parameters(self);
1168
1169 /* Always switch state before calling upper layers */
1170 irlap_next_state(self, LAP_NDM);
1171
1172 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1173 }
1174 break;
1175 default:
1176 IRDA_DEBUG(1, "%s(), Unknown event %d\n", __FUNCTION__, event);
1177
1178 ret = -1;
1179 break;
1180 }
1181 return ret;
1182}
1183
1184/*
1185 * Function irlap_state_nrm_p (self, event, skb, info)
1186 *
1187 * NRM_P (Normal Response Mode as Primary), The primary station has given
1188 * permissions to a secondary station to transmit IrLAP resonse frames
1189 * (by sending a frame with the P bit set). The primary station will not
1190 * transmit any frames and is expecting to receive frames only from the
1191 * secondary to which transmission permissions has been given.
1192 */
1193static int irlap_state_nrm_p(struct irlap_cb *self, IRLAP_EVENT event,
1194 struct sk_buff *skb, struct irlap_info *info)
1195{
1196 int ret = 0;
1197 int ns_status;
1198 int nr_status;
1199
1200 switch (event) {
1201 case RECV_I_RSP: /* Optimize for the common case */
1202 /* FIXME: must check for remote_busy below */
1203#ifdef CONFIG_IRDA_FAST_RR
1204 /*
1205 * Reset the fast_RR so we can use the fast RR code with
1206 * full speed the next time since peer may have more frames
1207 * to transmitt
1208 */
1209 self->fast_RR = FALSE;
1210#endif /* CONFIG_IRDA_FAST_RR */
1211 IRDA_ASSERT( info != NULL, return -1;);
1212
1213 ns_status = irlap_validate_ns_received(self, info->ns);
1214 nr_status = irlap_validate_nr_received(self, info->nr);
1215
1216 /*
1217 * Check for expected I(nformation) frame
1218 */
1219 if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1220
1221 /* Update Vr (next frame for us to receive) */
1222 self->vr = (self->vr + 1) % 8;
1223
1224 /* Update Nr received, cleanup our retry queue */
1225 irlap_update_nr_received(self, info->nr);
1226
1227 /*
1228 * Got expected NR, so reset the
1229 * retry_count. This is not done by IrLAP spec,
1230 * which is strange!
1231 */
1232 self->retry_count = 0;
1233 self->ack_required = TRUE;
1234
1235 /* poll bit cleared? */
1236 if (!info->pf) {
1237 /* Keep state, do not move this line */
1238 irlap_next_state(self, LAP_NRM_P);
1239
1240 irlap_data_indication(self, skb, FALSE);
1241 } else {
1242 /* No longer waiting for pf */
1243 del_timer(&self->final_timer);
1244
1245 irlap_wait_min_turn_around(self, &self->qos_tx);
1246
1247 /* Call higher layer *before* changing state
1248 * to give them a chance to send data in the
1249 * next LAP frame.
1250 * Jean II */
1251 irlap_data_indication(self, skb, FALSE);
1252
1253 /* XMIT states are the most dangerous state
1254 * to be in, because user requests are
1255 * processed directly and may change state.
1256 * On the other hand, in NDM_P, those
1257 * requests are queued and we will process
1258 * them when we return to irlap_do_event().
1259 * Jean II
1260 */
1261 irlap_next_state(self, LAP_XMIT_P);
1262
1263 /* This is the last frame.
1264 * Make sure it's always called in XMIT state.
1265 * - Jean II */
1266 irlap_start_poll_timer(self, self->poll_timeout);
1267 }
1268 break;
1269
1270 }
1271 /* Unexpected next to send (Ns) */
1272 if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1273 {
1274 if (!info->pf) {
1275 irlap_update_nr_received(self, info->nr);
1276
1277 /*
1278 * Wait until the last frame before doing
1279 * anything
1280 */
1281
1282 /* Keep state */
1283 irlap_next_state(self, LAP_NRM_P);
1284 } else {
1285 IRDA_DEBUG(4,
1286 "%s(), missing or duplicate frame!\n",
1287 __FUNCTION__);
1288
1289 /* Update Nr received */
1290 irlap_update_nr_received(self, info->nr);
1291
1292 irlap_wait_min_turn_around(self, &self->qos_tx);
1293 irlap_send_rr_frame(self, CMD_FRAME);
1294
1295 self->ack_required = FALSE;
1296
1297 irlap_start_final_timer(self, self->final_timeout);
1298 irlap_next_state(self, LAP_NRM_P);
1299 }
1300 break;
1301 }
1302 /*
1303 * Unexpected next to receive (Nr)
1304 */
1305 if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1306 {
1307 if (info->pf) {
1308 self->vr = (self->vr + 1) % 8;
1309
1310 /* Update Nr received */
1311 irlap_update_nr_received(self, info->nr);
1312
1313 /* Resend rejected frames */
1314 irlap_resend_rejected_frames(self, CMD_FRAME);
1315
1316 self->ack_required = FALSE;
1317
1318 /* Make sure we account for the time
1319 * to transmit our frames. See comemnts
1320 * in irlap_send_data_primary_poll().
1321 * Jean II */
1322 irlap_start_final_timer(self, 2 * self->final_timeout);
1323
1324 /* Keep state, do not move this line */
1325 irlap_next_state(self, LAP_NRM_P);
1326
1327 irlap_data_indication(self, skb, FALSE);
1328 } else {
1329 /*
1330 * Do not resend frames until the last
1331 * frame has arrived from the other
1332 * device. This is not documented in
1333 * IrLAP!!
1334 */
1335 self->vr = (self->vr + 1) % 8;
1336
1337 /* Update Nr received */
1338 irlap_update_nr_received(self, info->nr);
1339
1340 self->ack_required = FALSE;
1341
1342 /* Keep state, do not move this line!*/
1343 irlap_next_state(self, LAP_NRM_P);
1344
1345 irlap_data_indication(self, skb, FALSE);
1346 }
1347 break;
1348 }
1349 /*
1350 * Unexpected next to send (Ns) and next to receive (Nr)
1351 * Not documented by IrLAP!
1352 */
1353 if ((ns_status == NS_UNEXPECTED) &&
1354 (nr_status == NR_UNEXPECTED))
1355 {
1356 IRDA_DEBUG(4, "%s(), unexpected nr and ns!\n",
1357 __FUNCTION__);
1358 if (info->pf) {
1359 /* Resend rejected frames */
1360 irlap_resend_rejected_frames(self, CMD_FRAME);
1361
YOSHIFUJI Hideaki6819bc22007-02-09 23:24:53 +09001362 /* Give peer some time to retransmit!
Linus Torvalds1da177e2005-04-16 15:20:36 -07001363 * But account for our own Tx. */
1364 irlap_start_final_timer(self, 2 * self->final_timeout);
1365
1366 /* Keep state, do not move this line */
1367 irlap_next_state(self, LAP_NRM_P);
1368 } else {
1369 /* Update Nr received */
1370 /* irlap_update_nr_received( info->nr); */
1371
1372 self->ack_required = FALSE;
1373 }
1374 break;
1375 }
1376
1377 /*
1378 * Invalid NR or NS
1379 */
1380 if ((nr_status == NR_INVALID) || (ns_status == NS_INVALID)) {
1381 if (info->pf) {
1382 del_timer(&self->final_timer);
1383
1384 irlap_next_state(self, LAP_RESET_WAIT);
1385
1386 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1387 self->xmitflag = TRUE;
1388 } else {
1389 del_timer(&self->final_timer);
1390
1391 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1392
1393 self->xmitflag = FALSE;
1394 }
1395 break;
1396 }
1397 IRDA_DEBUG(1, "%s(), Not implemented!\n", __FUNCTION__);
1398 IRDA_DEBUG(1, "%s(), event=%s, ns_status=%d, nr_status=%d\n",
1399 __FUNCTION__, irlap_event[event], ns_status, nr_status);
1400 break;
1401 case RECV_UI_FRAME:
1402 /* Poll bit cleared? */
1403 if (!info->pf) {
1404 irlap_data_indication(self, skb, TRUE);
1405 irlap_next_state(self, LAP_NRM_P);
1406 } else {
1407 del_timer(&self->final_timer);
1408 irlap_data_indication(self, skb, TRUE);
1409 irlap_next_state(self, LAP_XMIT_P);
1410 IRDA_DEBUG(1, "%s: RECV_UI_FRAME: next state %s\n", __FUNCTION__, irlap_state[self->state]);
1411 irlap_start_poll_timer(self, self->poll_timeout);
1412 }
1413 break;
1414 case RECV_RR_RSP:
1415 /*
1416 * If you get a RR, the remote isn't busy anymore,
1417 * no matter what the NR
1418 */
1419 self->remote_busy = FALSE;
1420
G. Liakhovetskib7e773b2007-06-08 19:15:56 -07001421 /* Stop final timer */
1422 del_timer(&self->final_timer);
1423
Linus Torvalds1da177e2005-04-16 15:20:36 -07001424 /*
1425 * Nr as expected?
1426 */
1427 ret = irlap_validate_nr_received(self, info->nr);
1428 if (ret == NR_EXPECTED) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001429 /* Update Nr received */
1430 irlap_update_nr_received(self, info->nr);
1431
1432 /*
1433 * Got expected NR, so reset the retry_count. This
1434 * is not done by the IrLAP standard , which is
1435 * strange! DB.
1436 */
1437 self->retry_count = 0;
1438 irlap_wait_min_turn_around(self, &self->qos_tx);
1439
1440 irlap_next_state(self, LAP_XMIT_P);
1441
1442 /* Start poll timer */
1443 irlap_start_poll_timer(self, self->poll_timeout);
1444 } else if (ret == NR_UNEXPECTED) {
1445 IRDA_ASSERT(info != NULL, return -1;);
1446 /*
1447 * Unexpected nr!
1448 */
1449
1450 /* Update Nr received */
1451 irlap_update_nr_received(self, info->nr);
1452
1453 IRDA_DEBUG(4, "RECV_RR_FRAME: Retrans:%d, nr=%d, va=%d, "
1454 "vs=%d, vr=%d\n",
1455 self->retry_count, info->nr, self->va,
1456 self->vs, self->vr);
1457
1458 /* Resend rejected frames */
1459 irlap_resend_rejected_frames(self, CMD_FRAME);
G. Liakhovetskib7e773b2007-06-08 19:15:56 -07001460 irlap_start_final_timer(self, self->final_timeout * 2);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001461
1462 irlap_next_state(self, LAP_NRM_P);
1463 } else if (ret == NR_INVALID) {
1464 IRDA_DEBUG(1, "%s(), Received RR with "
1465 "invalid nr !\n", __FUNCTION__);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001466
1467 irlap_next_state(self, LAP_RESET_WAIT);
1468
1469 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1470 self->xmitflag = TRUE;
1471 }
1472 break;
1473 case RECV_RNR_RSP:
1474 IRDA_ASSERT(info != NULL, return -1;);
1475
1476 /* Stop final timer */
1477 del_timer(&self->final_timer);
1478 self->remote_busy = TRUE;
1479
1480 /* Update Nr received */
1481 irlap_update_nr_received(self, info->nr);
1482 irlap_next_state(self, LAP_XMIT_P);
1483
1484 /* Start poll timer */
1485 irlap_start_poll_timer(self, self->poll_timeout);
1486 break;
1487 case RECV_FRMR_RSP:
1488 del_timer(&self->final_timer);
1489 self->xmitflag = TRUE;
1490 irlap_next_state(self, LAP_RESET_WAIT);
1491 irlap_reset_indication(self);
1492 break;
1493 case FINAL_TIMER_EXPIRED:
1494 /*
1495 * We are allowed to wait for additional 300 ms if
1496 * final timer expires when we are in the middle
1497 * of receiving a frame (page 45, IrLAP). Check that
1498 * we only do this once for each frame.
1499 */
1500 if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
1501 IRDA_DEBUG(1, "FINAL_TIMER_EXPIRED when receiving a "
1502 "frame! Waiting a little bit more!\n");
1503 irlap_start_final_timer(self, msecs_to_jiffies(300));
1504
1505 /*
1506 * Don't allow this to happen one more time in a row,
1507 * or else we can get a pretty tight loop here if
1508 * if we only receive half a frame. DB.
1509 */
1510 self->add_wait = TRUE;
1511 break;
1512 }
1513 self->add_wait = FALSE;
1514
1515 /* N2 is the disconnect timer. Until we reach it, we retry */
1516 if (self->retry_count < self->N2) {
1517 /* Retry sending the pf bit to the secondary */
1518 irlap_wait_min_turn_around(self, &self->qos_tx);
1519 irlap_send_rr_frame(self, CMD_FRAME);
1520
1521 irlap_start_final_timer(self, self->final_timeout);
1522 self->retry_count++;
1523 IRDA_DEBUG(4, "irlap_state_nrm_p: FINAL_TIMER_EXPIRED:"
1524 " retry_count=%d\n", self->retry_count);
1525
1526 /* Early warning event. I'm using a pretty liberal
1527 * interpretation of the spec and generate an event
1528 * every time the timer is multiple of N1 (and not
1529 * only the first time). This allow application
1530 * to know precisely if connectivity restart...
1531 * Jean II */
1532 if((self->retry_count % self->N1) == 0)
1533 irlap_status_indication(self,
1534 STATUS_NO_ACTIVITY);
1535
1536 /* Keep state */
1537 } else {
1538 irlap_apply_default_connection_parameters(self);
1539
1540 /* Always switch state before calling upper layers */
1541 irlap_next_state(self, LAP_NDM);
1542 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1543 }
1544 break;
1545 case RECV_REJ_RSP:
1546 irlap_update_nr_received(self, info->nr);
1547 if (self->remote_busy) {
1548 irlap_wait_min_turn_around(self, &self->qos_tx);
1549 irlap_send_rr_frame(self, CMD_FRAME);
1550 } else
1551 irlap_resend_rejected_frames(self, CMD_FRAME);
1552 irlap_start_final_timer(self, 2 * self->final_timeout);
1553 break;
1554 case RECV_SREJ_RSP:
1555 irlap_update_nr_received(self, info->nr);
1556 if (self->remote_busy) {
1557 irlap_wait_min_turn_around(self, &self->qos_tx);
1558 irlap_send_rr_frame(self, CMD_FRAME);
1559 } else
1560 irlap_resend_rejected_frame(self, CMD_FRAME);
1561 irlap_start_final_timer(self, 2 * self->final_timeout);
1562 break;
1563 case RECV_RD_RSP:
1564 IRDA_DEBUG(1, "%s(), RECV_RD_RSP\n", __FUNCTION__);
1565
1566 irlap_flush_all_queues(self);
1567 irlap_next_state(self, LAP_XMIT_P);
1568 /* Call back the LAP state machine to do a proper disconnect */
1569 irlap_disconnect_request(self);
1570 break;
1571 default:
1572 IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1573 __FUNCTION__, irlap_event[event]);
1574
1575 ret = -1;
1576 break;
1577 }
1578 return ret;
1579}
1580
1581/*
1582 * Function irlap_state_reset_wait (event, skb, info)
1583 *
1584 * We have informed the service user of a reset condition, and is
1585 * awaiting reset of disconnect request.
1586 *
1587 */
1588static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
1589 struct sk_buff *skb, struct irlap_info *info)
1590{
1591 int ret = 0;
1592
1593 IRDA_DEBUG(3, "%s(), event = %s\n", __FUNCTION__, irlap_event[event]);
1594
1595 IRDA_ASSERT(self != NULL, return -1;);
1596 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1597
1598 switch (event) {
1599 case RESET_REQUEST:
1600 if (self->xmitflag) {
1601 irlap_wait_min_turn_around(self, &self->qos_tx);
1602 irlap_send_snrm_frame(self, NULL);
1603 irlap_start_final_timer(self, self->final_timeout);
1604 irlap_next_state(self, LAP_RESET);
1605 } else {
1606 irlap_start_final_timer(self, self->final_timeout);
1607 irlap_next_state(self, LAP_RESET);
1608 }
1609 break;
1610 case DISCONNECT_REQUEST:
1611 irlap_wait_min_turn_around( self, &self->qos_tx);
1612 irlap_send_disc_frame( self);
1613 irlap_flush_all_queues( self);
1614 irlap_start_final_timer( self, self->final_timeout);
1615 self->retry_count = 0;
1616 irlap_next_state( self, LAP_PCLOSE);
1617 break;
1618 default:
1619 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
1620 irlap_event[event]);
1621
1622 ret = -1;
1623 break;
1624 }
1625 return ret;
1626}
1627
1628/*
1629 * Function irlap_state_reset (self, event, skb, info)
1630 *
1631 * We have sent a SNRM reset command to the peer layer, and is awaiting
1632 * reply.
1633 *
1634 */
1635static int irlap_state_reset(struct irlap_cb *self, IRLAP_EVENT event,
1636 struct sk_buff *skb, struct irlap_info *info)
1637{
1638 int ret = 0;
1639
1640 IRDA_DEBUG(3, "%s(), event = %s\n", __FUNCTION__, irlap_event[event]);
1641
1642 IRDA_ASSERT(self != NULL, return -1;);
1643 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1644
1645 switch (event) {
1646 case RECV_DISC_CMD:
1647 del_timer(&self->final_timer);
1648
1649 irlap_apply_default_connection_parameters(self);
1650
1651 /* Always switch state before calling upper layers */
1652 irlap_next_state(self, LAP_NDM);
1653
1654 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1655
1656 break;
1657 case RECV_UA_RSP:
1658 del_timer(&self->final_timer);
1659
1660 /* Initiate connection state */
1661 irlap_initiate_connection_state(self);
1662
1663 irlap_reset_confirm();
1664
1665 self->remote_busy = FALSE;
1666
1667 irlap_next_state(self, LAP_XMIT_P);
1668
1669 irlap_start_poll_timer(self, self->poll_timeout);
1670
1671 break;
1672 case FINAL_TIMER_EXPIRED:
1673 if (self->retry_count < 3) {
1674 irlap_wait_min_turn_around(self, &self->qos_tx);
1675
1676 IRDA_ASSERT(self->netdev != NULL, return -1;);
1677 irlap_send_snrm_frame(self, self->qos_dev);
1678
1679 self->retry_count++; /* Experimental!! */
1680
1681 irlap_start_final_timer(self, self->final_timeout);
1682 irlap_next_state(self, LAP_RESET);
1683 } else if (self->retry_count >= self->N3) {
1684 irlap_apply_default_connection_parameters(self);
1685
1686 /* Always switch state before calling upper layers */
1687 irlap_next_state(self, LAP_NDM);
1688
1689 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1690 }
1691 break;
1692 case RECV_SNRM_CMD:
1693 /*
1694 * SNRM frame is not allowed to contain an I-field in this
1695 * state
1696 */
1697 if (!info) {
1698 IRDA_DEBUG(3, "%s(), RECV_SNRM_CMD\n", __FUNCTION__);
1699 irlap_initiate_connection_state(self);
1700 irlap_wait_min_turn_around(self, &self->qos_tx);
1701 irlap_send_ua_response_frame(self, &self->qos_rx);
1702 irlap_reset_confirm();
1703 irlap_start_wd_timer(self, self->wd_timeout);
1704 irlap_next_state(self, LAP_NDM);
1705 } else {
1706 IRDA_DEBUG(0,
1707 "%s(), SNRM frame contained an I field!\n",
1708 __FUNCTION__);
1709 }
1710 break;
1711 default:
1712 IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1713 __FUNCTION__, irlap_event[event]);
1714
1715 ret = -1;
1716 break;
1717 }
1718 return ret;
1719}
1720
1721/*
1722 * Function irlap_state_xmit_s (event, skb, info)
1723 *
1724 * XMIT_S, The secondary station has been given the right to transmit,
1725 * and we therefor do not expect to receive any transmissions from other
1726 * stations.
1727 */
1728static int irlap_state_xmit_s(struct irlap_cb *self, IRLAP_EVENT event,
1729 struct sk_buff *skb, struct irlap_info *info)
1730{
1731 int ret = 0;
1732
1733 IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[event]);
1734
1735 IRDA_ASSERT(self != NULL, return -ENODEV;);
1736 IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
1737
1738 switch (event) {
1739 case SEND_I_CMD:
1740 /*
1741 * Send frame only if send window > 0
1742 */
1743 if ((self->window > 0) && (!self->remote_busy)) {
1744 int nextfit;
1745#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1746 struct sk_buff *skb_next;
1747
1748 /*
1749 * Same deal as in irlap_state_xmit_p(), so see
1750 * the comments at that point.
1751 * We are the secondary, so there are only subtle
1752 * differences. - Jean II
1753 */
1754
1755 /* Check if a subsequent skb exist and would fit in
1756 * the current window (with respect to turnaround
1757 * time). - Jean II */
1758 skb_next = skb_peek(&self->txq);
1759 nextfit = ((skb_next != NULL) &&
1760 ((skb_next->len + skb->len) <=
1761 self->bytes_left));
1762
1763 /*
1764 * Test if we have transmitted more bytes over the
1765 * link than its possible to do with the current
1766 * speed and turn-around-time.
1767 */
1768 if((!nextfit) && (skb->len > self->bytes_left)) {
1769 IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1770 " more bytes!\n", __FUNCTION__);
1771 /* Requeue the skb */
1772 skb_queue_head(&self->txq, skb_get(skb));
1773
1774 /*
1775 * Switch to NRM_S, this is only possible
1776 * when we are in secondary mode, since we
1777 * must be sure that we don't miss any RR
1778 * frames
1779 */
1780 self->window = self->window_size;
1781 self->bytes_left = self->line_capacity;
1782 irlap_start_wd_timer(self, self->wd_timeout);
1783
1784 irlap_next_state(self, LAP_NRM_S);
1785 /* Slight difference with primary :
1786 * here we would wait for the other side to
1787 * expire the turnaround. - Jean II */
1788
1789 return -EPROTO; /* Try again later */
1790 }
1791 /* Substract space used by this skb */
1792 self->bytes_left -= skb->len;
1793#else /* CONFIG_IRDA_DYNAMIC_WINDOW */
1794 /* Window has been adjusted for the max packet
1795 * size, so much simpler... - Jean II */
David S. Millerb03efcf2005-07-08 14:57:23 -07001796 nextfit = !skb_queue_empty(&self->txq);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001797#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1798 /*
1799 * Send data with final bit cleared only if window > 1
1800 * and there is more frames to be sent
1801 */
1802 if ((self->window > 1) && (nextfit)) {
1803 irlap_send_data_secondary(self, skb);
1804 irlap_next_state(self, LAP_XMIT_S);
1805 } else {
1806 irlap_send_data_secondary_final(self, skb);
1807 irlap_next_state(self, LAP_NRM_S);
1808
1809 /*
1810 * Make sure state machine does not try to send
1811 * any more frames
1812 */
1813 ret = -EPROTO;
1814 }
1815 } else {
1816 IRDA_DEBUG(2, "%s(), Unable to send!\n", __FUNCTION__);
1817 skb_queue_head(&self->txq, skb_get(skb));
1818 ret = -EPROTO;
1819 }
1820 break;
1821 case DISCONNECT_REQUEST:
1822 irlap_send_rd_frame(self);
1823 irlap_flush_all_queues(self);
1824 irlap_start_wd_timer(self, self->wd_timeout);
1825 irlap_next_state(self, LAP_SCLOSE);
1826 break;
1827 case DATA_REQUEST:
1828 /* Nothing to do, irlap_do_event() will send the packet
1829 * when we return... - Jean II */
1830 break;
1831 default:
1832 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
1833 irlap_event[event]);
1834
1835 ret = -EINVAL;
1836 break;
1837 }
1838 return ret;
1839}
1840
1841/*
1842 * Function irlap_state_nrm_s (event, skb, info)
1843 *
1844 * NRM_S (Normal Response Mode as Secondary) state, in this state we are
1845 * expecting to receive frames from the primary station
1846 *
1847 */
1848static int irlap_state_nrm_s(struct irlap_cb *self, IRLAP_EVENT event,
1849 struct sk_buff *skb, struct irlap_info *info)
1850{
1851 int ns_status;
1852 int nr_status;
1853 int ret = 0;
1854
1855 IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[ event]);
1856
1857 IRDA_ASSERT(self != NULL, return -1;);
1858 IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1859
1860 switch (event) {
1861 case RECV_I_CMD: /* Optimize for the common case */
1862 /* FIXME: must check for remote_busy below */
1863 IRDA_DEBUG(4, "%s(), event=%s nr=%d, vs=%d, ns=%d, "
1864 "vr=%d, pf=%d\n", __FUNCTION__,
1865 irlap_event[event], info->nr,
1866 self->vs, info->ns, self->vr, info->pf);
1867
1868 self->retry_count = 0;
1869
1870 ns_status = irlap_validate_ns_received(self, info->ns);
1871 nr_status = irlap_validate_nr_received(self, info->nr);
1872 /*
1873 * Check for expected I(nformation) frame
1874 */
1875 if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1876
1877 /* Update Vr (next frame for us to receive) */
1878 self->vr = (self->vr + 1) % 8;
1879
1880 /* Update Nr received */
1881 irlap_update_nr_received(self, info->nr);
1882
1883 /*
1884 * poll bit cleared?
1885 */
1886 if (!info->pf) {
1887
1888 self->ack_required = TRUE;
1889
1890 /*
1891 * Starting WD-timer here is optional, but
1892 * not recommended. Note 6 IrLAP p. 83
1893 */
1894#if 0
1895 irda_start_timer(WD_TIMER, self->wd_timeout);
1896#endif
1897 /* Keep state, do not move this line */
1898 irlap_next_state(self, LAP_NRM_S);
1899
1900 irlap_data_indication(self, skb, FALSE);
1901 break;
1902 } else {
1903 /*
1904 * We should wait before sending RR, and
1905 * also before changing to XMIT_S
1906 * state. (note 1, IrLAP p. 82)
1907 */
1908 irlap_wait_min_turn_around(self, &self->qos_tx);
1909
1910 /*
1911 * Give higher layers a chance to
1912 * immediately reply with some data before
1913 * we decide if we should send a RR frame
1914 * or not
1915 */
1916 irlap_data_indication(self, skb, FALSE);
1917
1918 /* Any pending data requests? */
David S. Millerb03efcf2005-07-08 14:57:23 -07001919 if (!skb_queue_empty(&self->txq) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07001920 (self->window > 0))
1921 {
1922 self->ack_required = TRUE;
1923
1924 del_timer(&self->wd_timer);
1925
1926 irlap_next_state(self, LAP_XMIT_S);
1927 } else {
1928 irlap_send_rr_frame(self, RSP_FRAME);
1929 irlap_start_wd_timer(self,
1930 self->wd_timeout);
1931
1932 /* Keep the state */
1933 irlap_next_state(self, LAP_NRM_S);
1934 }
1935 break;
1936 }
1937 }
1938 /*
1939 * Check for Unexpected next to send (Ns)
1940 */
1941 if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1942 {
1943 /* Unexpected next to send, with final bit cleared */
1944 if (!info->pf) {
1945 irlap_update_nr_received(self, info->nr);
1946
1947 irlap_start_wd_timer(self, self->wd_timeout);
1948 } else {
1949 /* Update Nr received */
1950 irlap_update_nr_received(self, info->nr);
1951
1952 irlap_wait_min_turn_around(self, &self->qos_tx);
1953 irlap_send_rr_frame(self, RSP_FRAME);
1954
1955 irlap_start_wd_timer(self, self->wd_timeout);
1956 }
1957 break;
1958 }
1959
1960 /*
1961 * Unexpected Next to Receive(NR) ?
1962 */
1963 if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1964 {
1965 if (info->pf) {
1966 IRDA_DEBUG(4, "RECV_I_RSP: frame(s) lost\n");
1967
1968 self->vr = (self->vr + 1) % 8;
1969
1970 /* Update Nr received */
1971 irlap_update_nr_received(self, info->nr);
1972
1973 /* Resend rejected frames */
1974 irlap_resend_rejected_frames(self, RSP_FRAME);
1975
1976 /* Keep state, do not move this line */
1977 irlap_next_state(self, LAP_NRM_S);
1978
1979 irlap_data_indication(self, skb, FALSE);
1980 irlap_start_wd_timer(self, self->wd_timeout);
1981 break;
1982 }
1983 /*
1984 * This is not documented in IrLAP!! Unexpected NR
1985 * with poll bit cleared
1986 */
1987 if (!info->pf) {
1988 self->vr = (self->vr + 1) % 8;
1989
1990 /* Update Nr received */
1991 irlap_update_nr_received(self, info->nr);
1992
1993 /* Keep state, do not move this line */
1994 irlap_next_state(self, LAP_NRM_S);
1995
1996 irlap_data_indication(self, skb, FALSE);
1997 irlap_start_wd_timer(self, self->wd_timeout);
1998 }
1999 break;
2000 }
2001
2002 if (ret == NR_INVALID) {
2003 IRDA_DEBUG(0, "NRM_S, NR_INVALID not implemented!\n");
2004 }
2005 if (ret == NS_INVALID) {
2006 IRDA_DEBUG(0, "NRM_S, NS_INVALID not implemented!\n");
2007 }
2008 break;
2009 case RECV_UI_FRAME:
2010 /*
2011 * poll bit cleared?
2012 */
2013 if (!info->pf) {
2014 irlap_data_indication(self, skb, TRUE);
2015 irlap_next_state(self, LAP_NRM_S); /* Keep state */
2016 } else {
2017 /*
2018 * Any pending data requests?
2019 */
David S. Millerb03efcf2005-07-08 14:57:23 -07002020 if (!skb_queue_empty(&self->txq) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07002021 (self->window > 0) && !self->remote_busy)
2022 {
2023 irlap_data_indication(self, skb, TRUE);
2024
2025 del_timer(&self->wd_timer);
2026
2027 irlap_next_state(self, LAP_XMIT_S);
2028 } else {
2029 irlap_data_indication(self, skb, TRUE);
2030
2031 irlap_wait_min_turn_around(self, &self->qos_tx);
2032
2033 irlap_send_rr_frame(self, RSP_FRAME);
2034 self->ack_required = FALSE;
2035
2036 irlap_start_wd_timer(self, self->wd_timeout);
2037
2038 /* Keep the state */
2039 irlap_next_state(self, LAP_NRM_S);
2040 }
2041 }
2042 break;
2043 case RECV_RR_CMD:
2044 self->retry_count = 0;
2045
2046 /*
2047 * Nr as expected?
2048 */
2049 nr_status = irlap_validate_nr_received(self, info->nr);
2050 if (nr_status == NR_EXPECTED) {
David S. Millerb03efcf2005-07-08 14:57:23 -07002051 if (!skb_queue_empty(&self->txq) &&
Linus Torvalds1da177e2005-04-16 15:20:36 -07002052 (self->window > 0)) {
2053 self->remote_busy = FALSE;
2054
2055 /* Update Nr received */
2056 irlap_update_nr_received(self, info->nr);
2057 del_timer(&self->wd_timer);
2058
2059 irlap_wait_min_turn_around(self, &self->qos_tx);
2060 irlap_next_state(self, LAP_XMIT_S);
2061 } else {
2062 self->remote_busy = FALSE;
2063 /* Update Nr received */
2064 irlap_update_nr_received(self, info->nr);
2065 irlap_wait_min_turn_around(self, &self->qos_tx);
2066 irlap_start_wd_timer(self, self->wd_timeout);
2067
2068 /* Note : if the link is idle (this case),
2069 * we never go in XMIT_S, so we never get a
2070 * chance to process any DISCONNECT_REQUEST.
2071 * Do it now ! - Jean II */
2072 if (self->disconnect_pending) {
2073 /* Disconnect */
2074 irlap_send_rd_frame(self);
2075 irlap_flush_all_queues(self);
2076
2077 irlap_next_state(self, LAP_SCLOSE);
2078 } else {
2079 /* Just send back pf bit */
2080 irlap_send_rr_frame(self, RSP_FRAME);
2081
2082 irlap_next_state(self, LAP_NRM_S);
2083 }
2084 }
2085 } else if (nr_status == NR_UNEXPECTED) {
2086 self->remote_busy = FALSE;
2087 irlap_update_nr_received(self, info->nr);
2088 irlap_resend_rejected_frames(self, RSP_FRAME);
2089
2090 irlap_start_wd_timer(self, self->wd_timeout);
2091
2092 /* Keep state */
2093 irlap_next_state(self, LAP_NRM_S);
2094 } else {
2095 IRDA_DEBUG(1, "%s(), invalid nr not implemented!\n",
2096 __FUNCTION__);
2097 }
2098 break;
2099 case RECV_SNRM_CMD:
2100 /* SNRM frame is not allowed to contain an I-field */
2101 if (!info) {
2102 del_timer(&self->wd_timer);
2103 IRDA_DEBUG(1, "%s(), received SNRM cmd\n", __FUNCTION__);
2104 irlap_next_state(self, LAP_RESET_CHECK);
2105
2106 irlap_reset_indication(self);
2107 } else {
2108 IRDA_DEBUG(0,
2109 "%s(), SNRM frame contained an I-field!\n",
2110 __FUNCTION__);
2111
2112 }
2113 break;
2114 case RECV_REJ_CMD:
2115 irlap_update_nr_received(self, info->nr);
2116 if (self->remote_busy) {
2117 irlap_wait_min_turn_around(self, &self->qos_tx);
2118 irlap_send_rr_frame(self, RSP_FRAME);
2119 } else
2120 irlap_resend_rejected_frames(self, RSP_FRAME);
2121 irlap_start_wd_timer(self, self->wd_timeout);
2122 break;
2123 case RECV_SREJ_CMD:
2124 irlap_update_nr_received(self, info->nr);
2125 if (self->remote_busy) {
2126 irlap_wait_min_turn_around(self, &self->qos_tx);
2127 irlap_send_rr_frame(self, RSP_FRAME);
2128 } else
2129 irlap_resend_rejected_frame(self, RSP_FRAME);
2130 irlap_start_wd_timer(self, self->wd_timeout);
2131 break;
2132 case WD_TIMER_EXPIRED:
2133 /*
2134 * Wait until retry_count * n matches negotiated threshold/
2135 * disconnect time (note 2 in IrLAP p. 82)
2136 *
2137 * Similar to irlap_state_nrm_p() -> FINAL_TIMER_EXPIRED
2138 * Note : self->wd_timeout = (self->final_timeout * 2),
2139 * which explain why we use (self->N2 / 2) here !!!
2140 * Jean II
2141 */
2142 IRDA_DEBUG(1, "%s(), retry_count = %d\n", __FUNCTION__,
2143 self->retry_count);
2144
2145 if (self->retry_count < (self->N2 / 2)) {
2146 /* No retry, just wait for primary */
2147 irlap_start_wd_timer(self, self->wd_timeout);
2148 self->retry_count++;
2149
2150 if((self->retry_count % (self->N1 / 2)) == 0)
2151 irlap_status_indication(self,
2152 STATUS_NO_ACTIVITY);
2153 } else {
2154 irlap_apply_default_connection_parameters(self);
2155
2156 /* Always switch state before calling upper layers */
2157 irlap_next_state(self, LAP_NDM);
2158 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
2159 }
2160 break;
2161 case RECV_DISC_CMD:
2162 /* Always switch state before calling upper layers */
2163 irlap_next_state(self, LAP_NDM);
2164
2165 /* Send disconnect response */
2166 irlap_wait_min_turn_around(self, &self->qos_tx);
2167 irlap_send_ua_response_frame(self, NULL);
2168
2169 del_timer(&self->wd_timer);
2170 irlap_flush_all_queues(self);
2171 /* Set default link parameters */
2172 irlap_apply_default_connection_parameters(self);
2173
2174 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2175 break;
2176 case RECV_DISCOVERY_XID_CMD:
2177 irlap_wait_min_turn_around(self, &self->qos_tx);
2178 irlap_send_rr_frame(self, RSP_FRAME);
2179 self->ack_required = TRUE;
2180 irlap_start_wd_timer(self, self->wd_timeout);
2181 irlap_next_state(self, LAP_NRM_S);
2182
2183 break;
2184 case RECV_TEST_CMD:
2185 /* Remove test frame header (only LAP header in NRM) */
2186 skb_pull(skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
2187
2188 irlap_wait_min_turn_around(self, &self->qos_tx);
2189 irlap_start_wd_timer(self, self->wd_timeout);
2190
2191 /* Send response (info will be copied) */
2192 irlap_send_test_frame(self, self->caddr, info->daddr, skb);
2193 break;
2194 default:
2195 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2196 event, irlap_event[event]);
2197
2198 ret = -EINVAL;
2199 break;
2200 }
2201 return ret;
2202}
2203
2204/*
2205 * Function irlap_state_sclose (self, event, skb, info)
2206 */
2207static int irlap_state_sclose(struct irlap_cb *self, IRLAP_EVENT event,
2208 struct sk_buff *skb, struct irlap_info *info)
2209{
2210 int ret = 0;
2211
2212 IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
2213
2214 IRDA_ASSERT(self != NULL, return -ENODEV;);
2215 IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2216
2217 switch (event) {
2218 case RECV_DISC_CMD:
2219 /* Always switch state before calling upper layers */
2220 irlap_next_state(self, LAP_NDM);
2221
2222 /* Send disconnect response */
2223 irlap_wait_min_turn_around(self, &self->qos_tx);
2224 irlap_send_ua_response_frame(self, NULL);
2225
2226 del_timer(&self->wd_timer);
2227 /* Set default link parameters */
2228 irlap_apply_default_connection_parameters(self);
2229
2230 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2231 break;
2232 case RECV_DM_RSP:
2233 /* IrLAP-1.1 p.82: in SCLOSE, S and I type RSP frames
2234 * shall take us down into default NDM state, like DM_RSP
2235 */
2236 case RECV_RR_RSP:
2237 case RECV_RNR_RSP:
2238 case RECV_REJ_RSP:
2239 case RECV_SREJ_RSP:
2240 case RECV_I_RSP:
2241 /* Always switch state before calling upper layers */
2242 irlap_next_state(self, LAP_NDM);
2243
2244 del_timer(&self->wd_timer);
2245 irlap_apply_default_connection_parameters(self);
2246
2247 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2248 break;
2249 case WD_TIMER_EXPIRED:
2250 /* Always switch state before calling upper layers */
2251 irlap_next_state(self, LAP_NDM);
2252
2253 irlap_apply_default_connection_parameters(self);
2254
2255 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2256 break;
2257 default:
2258 /* IrLAP-1.1 p.82: in SCLOSE, basically any received frame
2259 * with pf=1 shall restart the wd-timer and resend the rd:rsp
2260 */
2261 if (info != NULL && info->pf) {
2262 del_timer(&self->wd_timer);
2263 irlap_wait_min_turn_around(self, &self->qos_tx);
2264 irlap_send_rd_frame(self);
2265 irlap_start_wd_timer(self, self->wd_timeout);
2266 break; /* stay in SCLOSE */
2267 }
2268
2269 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2270 event, irlap_event[event]);
2271
2272 ret = -EINVAL;
2273 break;
2274 }
2275
2276 return -1;
2277}
2278
2279static int irlap_state_reset_check( struct irlap_cb *self, IRLAP_EVENT event,
2280 struct sk_buff *skb,
2281 struct irlap_info *info)
2282{
2283 int ret = 0;
2284
2285 IRDA_DEBUG(1, "%s(), event=%s\n", __FUNCTION__, irlap_event[event]);
2286
2287 IRDA_ASSERT(self != NULL, return -ENODEV;);
2288 IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2289
2290 switch (event) {
2291 case RESET_RESPONSE:
2292 irlap_send_ua_response_frame(self, &self->qos_rx);
2293 irlap_initiate_connection_state(self);
2294 irlap_start_wd_timer(self, WD_TIMEOUT);
2295 irlap_flush_all_queues(self);
2296
2297 irlap_next_state(self, LAP_NRM_S);
2298 break;
2299 case DISCONNECT_REQUEST:
2300 irlap_wait_min_turn_around(self, &self->qos_tx);
2301 irlap_send_rd_frame(self);
2302 irlap_start_wd_timer(self, WD_TIMEOUT);
2303 irlap_next_state(self, LAP_SCLOSE);
2304 break;
2305 default:
2306 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2307 event, irlap_event[event]);
2308
2309 ret = -EINVAL;
2310 break;
2311 }
2312 return ret;
2313}