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