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awilliam
GitHub Repository: awilliam/linux-vfio
Path: blob/master/net/irda/irlap_event.c
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1
/*********************************************************************
2
*
3
* Filename: irlap_event.c
4
* Version: 0.9
5
* Description: IrLAP state machine implementation
6
* Status: Experimental.
7
* Author: Dag Brattli <[email protected]>
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* Created at: Sat Aug 16 00:59:29 1997
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* Modified at: Sat Dec 25 21:07:57 1999
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* Modified by: Dag Brattli <[email protected]>
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*
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* Copyright (c) 1998-2000 Dag Brattli <[email protected]>,
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* Copyright (c) 1998 Thomas Davis <[email protected]>
14
* All Rights Reserved.
15
* Copyright (c) 2000-2003 Jean Tourrilhes <[email protected]>
16
*
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* 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
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* 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
28
#include <linux/string.h>
29
#include <linux/kernel.h>
30
#include <linux/delay.h>
31
#include <linux/skbuff.h>
32
#include <linux/slab.h>
33
34
#include <net/irda/irda.h>
35
#include <net/irda/irlap_event.h>
36
37
#include <net/irda/timer.h>
38
#include <net/irda/irlap.h>
39
#include <net/irda/irlap_frame.h>
40
#include <net/irda/qos.h>
41
#include <net/irda/parameters.h>
42
#include <net/irda/irlmp.h> /* irlmp_flow_indication(), ... */
43
44
#include <net/irda/irda_device.h>
45
46
#ifdef CONFIG_IRDA_FAST_RR
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int sysctl_fast_poll_increase = 50;
48
#endif
49
50
static int irlap_state_ndm (struct irlap_cb *self, IRLAP_EVENT event,
51
struct sk_buff *skb, struct irlap_info *info);
52
static int irlap_state_query (struct irlap_cb *self, IRLAP_EVENT event,
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struct sk_buff *skb, struct irlap_info *info);
54
static int irlap_state_reply (struct irlap_cb *self, IRLAP_EVENT event,
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struct sk_buff *skb, struct irlap_info *info);
56
static int irlap_state_conn (struct irlap_cb *self, IRLAP_EVENT event,
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struct sk_buff *skb, struct irlap_info *info);
58
static int irlap_state_setup (struct irlap_cb *self, IRLAP_EVENT event,
59
struct sk_buff *skb, struct irlap_info *info);
60
static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
61
struct sk_buff *skb, struct irlap_info *info);
62
static int irlap_state_xmit_p (struct irlap_cb *self, IRLAP_EVENT event,
63
struct sk_buff *skb, struct irlap_info *info);
64
static int irlap_state_pclose (struct irlap_cb *self, IRLAP_EVENT event,
65
struct sk_buff *skb, struct irlap_info *info);
66
static int irlap_state_nrm_p (struct irlap_cb *self, IRLAP_EVENT event,
67
struct sk_buff *skb, struct irlap_info *info);
68
static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
69
struct sk_buff *skb, struct irlap_info *info);
70
static int irlap_state_reset (struct irlap_cb *self, IRLAP_EVENT event,
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struct sk_buff *skb, struct irlap_info *info);
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static int irlap_state_nrm_s (struct irlap_cb *self, IRLAP_EVENT event,
73
struct sk_buff *skb, struct irlap_info *info);
74
static int irlap_state_xmit_s (struct irlap_cb *self, IRLAP_EVENT event,
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struct sk_buff *skb, struct irlap_info *info);
76
static int irlap_state_sclose (struct irlap_cb *self, IRLAP_EVENT event,
77
struct sk_buff *skb, struct irlap_info *info);
78
static int irlap_state_reset_check(struct irlap_cb *, IRLAP_EVENT event,
79
struct sk_buff *, struct irlap_info *);
80
81
#ifdef CONFIG_IRDA_DEBUG
82
static const char *const irlap_event[] = {
83
"DISCOVERY_REQUEST",
84
"CONNECT_REQUEST",
85
"CONNECT_RESPONSE",
86
"DISCONNECT_REQUEST",
87
"DATA_REQUEST",
88
"RESET_REQUEST",
89
"RESET_RESPONSE",
90
"SEND_I_CMD",
91
"SEND_UI_FRAME",
92
"RECV_DISCOVERY_XID_CMD",
93
"RECV_DISCOVERY_XID_RSP",
94
"RECV_SNRM_CMD",
95
"RECV_TEST_CMD",
96
"RECV_TEST_RSP",
97
"RECV_UA_RSP",
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"RECV_DM_RSP",
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"RECV_RD_RSP",
100
"RECV_I_CMD",
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"RECV_I_RSP",
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"RECV_UI_FRAME",
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"RECV_FRMR_RSP",
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"RECV_RR_CMD",
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"RECV_RR_RSP",
106
"RECV_RNR_CMD",
107
"RECV_RNR_RSP",
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"RECV_REJ_CMD",
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"RECV_REJ_RSP",
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"RECV_SREJ_CMD",
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"RECV_SREJ_RSP",
112
"RECV_DISC_CMD",
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"SLOT_TIMER_EXPIRED",
114
"QUERY_TIMER_EXPIRED",
115
"FINAL_TIMER_EXPIRED",
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"POLL_TIMER_EXPIRED",
117
"DISCOVERY_TIMER_EXPIRED",
118
"WD_TIMER_EXPIRED",
119
"BACKOFF_TIMER_EXPIRED",
120
"MEDIA_BUSY_TIMER_EXPIRED",
121
};
122
#endif /* CONFIG_IRDA_DEBUG */
123
124
const char *const irlap_state[] = {
125
"LAP_NDM",
126
"LAP_QUERY",
127
"LAP_REPLY",
128
"LAP_CONN",
129
"LAP_SETUP",
130
"LAP_OFFLINE",
131
"LAP_XMIT_P",
132
"LAP_PCLOSE",
133
"LAP_NRM_P",
134
"LAP_RESET_WAIT",
135
"LAP_RESET",
136
"LAP_NRM_S",
137
"LAP_XMIT_S",
138
"LAP_SCLOSE",
139
"LAP_RESET_CHECK",
140
};
141
142
static int (*state[])(struct irlap_cb *self, IRLAP_EVENT event,
143
struct sk_buff *skb, struct irlap_info *info) =
144
{
145
irlap_state_ndm,
146
irlap_state_query,
147
irlap_state_reply,
148
irlap_state_conn,
149
irlap_state_setup,
150
irlap_state_offline,
151
irlap_state_xmit_p,
152
irlap_state_pclose,
153
irlap_state_nrm_p,
154
irlap_state_reset_wait,
155
irlap_state_reset,
156
irlap_state_nrm_s,
157
irlap_state_xmit_s,
158
irlap_state_sclose,
159
irlap_state_reset_check,
160
};
161
162
/*
163
* Function irda_poll_timer_expired (data)
164
*
165
* Poll timer has expired. Normally we must now send a RR frame to the
166
* remote device
167
*/
168
static void irlap_poll_timer_expired(void *data)
169
{
170
struct irlap_cb *self = (struct irlap_cb *) data;
171
172
IRDA_ASSERT(self != NULL, return;);
173
IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
174
175
irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
176
}
177
178
/*
179
* Calculate and set time before we will have to send back the pf bit
180
* to the peer. Use in primary.
181
* Make sure that state is XMIT_P/XMIT_S when calling this function
182
* (and that nobody messed up with the state). - Jean II
183
*/
184
static void irlap_start_poll_timer(struct irlap_cb *self, int timeout)
185
{
186
IRDA_ASSERT(self != NULL, return;);
187
IRDA_ASSERT(self->magic == LAP_MAGIC, return;);
188
189
#ifdef CONFIG_IRDA_FAST_RR
190
/*
191
* Send out the RR frames faster if our own transmit queue is empty, or
192
* if the peer is busy. The effect is a much faster conversation
193
*/
194
if (skb_queue_empty(&self->txq) || self->remote_busy) {
195
if (self->fast_RR == TRUE) {
196
/*
197
* Assert that the fast poll timer has not reached the
198
* normal poll timer yet
199
*/
200
if (self->fast_RR_timeout < timeout) {
201
/*
202
* FIXME: this should be a more configurable
203
* function
204
*/
205
self->fast_RR_timeout +=
206
(sysctl_fast_poll_increase * HZ/1000);
207
208
/* Use this fast(er) timeout instead */
209
timeout = self->fast_RR_timeout;
210
}
211
} else {
212
self->fast_RR = TRUE;
213
214
/* Start with just 0 ms */
215
self->fast_RR_timeout = 0;
216
timeout = 0;
217
}
218
} else
219
self->fast_RR = FALSE;
220
221
IRDA_DEBUG(3, "%s(), timeout=%d (%ld)\n", __func__, timeout, jiffies);
222
#endif /* CONFIG_IRDA_FAST_RR */
223
224
if (timeout == 0)
225
irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
226
else
227
irda_start_timer(&self->poll_timer, timeout, self,
228
irlap_poll_timer_expired);
229
}
230
231
/*
232
* Function irlap_do_event (event, skb, info)
233
*
234
* Rushes through the state machine without any delay. If state == XMIT
235
* then send queued data frames.
236
*/
237
void irlap_do_event(struct irlap_cb *self, IRLAP_EVENT event,
238
struct sk_buff *skb, struct irlap_info *info)
239
{
240
int ret;
241
242
if (!self || self->magic != LAP_MAGIC)
243
return;
244
245
IRDA_DEBUG(3, "%s(), event = %s, state = %s\n", __func__,
246
irlap_event[event], irlap_state[self->state]);
247
248
ret = (*state[self->state])(self, event, skb, info);
249
250
/*
251
* Check if there are any pending events that needs to be executed
252
*/
253
switch (self->state) {
254
case LAP_XMIT_P: /* FALLTHROUGH */
255
case LAP_XMIT_S:
256
/*
257
* We just received the pf bit and are at the beginning
258
* of a new LAP transmit window.
259
* Check if there are any queued data frames, and do not
260
* try to disconnect link if we send any data frames, since
261
* that will change the state away form XMIT
262
*/
263
IRDA_DEBUG(2, "%s() : queue len = %d\n", __func__,
264
skb_queue_len(&self->txq));
265
266
if (!skb_queue_empty(&self->txq)) {
267
/* Prevent race conditions with irlap_data_request() */
268
self->local_busy = TRUE;
269
270
/* Theory of operation.
271
* We send frames up to when we fill the window or
272
* reach line capacity. Those frames will queue up
273
* in the device queue, and the driver will slowly
274
* send them.
275
* After each frame that we send, we poll the higher
276
* layer for more data. It's the right time to do
277
* that because the link layer need to perform the mtt
278
* and then send the first frame, so we can afford
279
* to send a bit of time in kernel space.
280
* The explicit flow indication allow to minimise
281
* buffers (== lower latency), to avoid higher layer
282
* polling via timers (== less context switches) and
283
* to implement a crude scheduler - Jean II */
284
285
/* Try to send away all queued data frames */
286
while ((skb = skb_dequeue(&self->txq)) != NULL) {
287
/* Send one frame */
288
ret = (*state[self->state])(self, SEND_I_CMD,
289
skb, NULL);
290
/* Drop reference count.
291
* It will be increase as needed in
292
* irlap_send_data_xxx() */
293
kfree_skb(skb);
294
295
/* Poll the higher layers for one more frame */
296
irlmp_flow_indication(self->notify.instance,
297
FLOW_START);
298
299
if (ret == -EPROTO)
300
break; /* Try again later! */
301
}
302
/* Finished transmitting */
303
self->local_busy = FALSE;
304
} else if (self->disconnect_pending) {
305
self->disconnect_pending = FALSE;
306
307
ret = (*state[self->state])(self, DISCONNECT_REQUEST,
308
NULL, NULL);
309
}
310
break;
311
/* case LAP_NDM: */
312
/* case LAP_CONN: */
313
/* case LAP_RESET_WAIT: */
314
/* case LAP_RESET_CHECK: */
315
default:
316
break;
317
}
318
}
319
320
/*
321
* Function irlap_state_ndm (event, skb, frame)
322
*
323
* NDM (Normal Disconnected Mode) state
324
*
325
*/
326
static int irlap_state_ndm(struct irlap_cb *self, IRLAP_EVENT event,
327
struct sk_buff *skb, struct irlap_info *info)
328
{
329
discovery_t *discovery_rsp;
330
int ret = 0;
331
332
IRDA_ASSERT(self != NULL, return -1;);
333
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
334
335
switch (event) {
336
case CONNECT_REQUEST:
337
IRDA_ASSERT(self->netdev != NULL, return -1;);
338
339
if (self->media_busy) {
340
/* Note : this will never happen, because we test
341
* media busy in irlap_connect_request() and
342
* postpone the event... - Jean II */
343
IRDA_DEBUG(0, "%s(), CONNECT_REQUEST: media busy!\n",
344
__func__);
345
346
/* Always switch state before calling upper layers */
347
irlap_next_state(self, LAP_NDM);
348
349
irlap_disconnect_indication(self, LAP_MEDIA_BUSY);
350
} else {
351
irlap_send_snrm_frame(self, &self->qos_rx);
352
353
/* Start Final-bit timer */
354
irlap_start_final_timer(self, self->final_timeout);
355
356
self->retry_count = 0;
357
irlap_next_state(self, LAP_SETUP);
358
}
359
break;
360
case RECV_SNRM_CMD:
361
/* Check if the frame contains and I field */
362
if (info) {
363
self->daddr = info->daddr;
364
self->caddr = info->caddr;
365
366
irlap_next_state(self, LAP_CONN);
367
368
irlap_connect_indication(self, skb);
369
} else {
370
IRDA_DEBUG(0, "%s(), SNRM frame does not "
371
"contain an I field!\n", __func__);
372
}
373
break;
374
case DISCOVERY_REQUEST:
375
IRDA_ASSERT(info != NULL, return -1;);
376
377
if (self->media_busy) {
378
IRDA_DEBUG(1, "%s(), DISCOVERY_REQUEST: media busy!\n",
379
__func__);
380
/* irlap->log.condition = MEDIA_BUSY; */
381
382
/* This will make IrLMP try again */
383
irlap_discovery_confirm(self, NULL);
384
/* Note : the discovery log is not cleaned up here,
385
* it will be done in irlap_discovery_request()
386
* Jean II */
387
return 0;
388
}
389
390
self->S = info->S;
391
self->s = info->s;
392
irlap_send_discovery_xid_frame(self, info->S, info->s, TRUE,
393
info->discovery);
394
self->frame_sent = FALSE;
395
self->s++;
396
397
irlap_start_slot_timer(self, self->slot_timeout);
398
irlap_next_state(self, LAP_QUERY);
399
break;
400
case RECV_DISCOVERY_XID_CMD:
401
IRDA_ASSERT(info != NULL, return -1;);
402
403
/* Assert that this is not the final slot */
404
if (info->s <= info->S) {
405
self->slot = irlap_generate_rand_time_slot(info->S,
406
info->s);
407
if (self->slot == info->s) {
408
discovery_rsp = irlmp_get_discovery_response();
409
discovery_rsp->data.daddr = info->daddr;
410
411
irlap_send_discovery_xid_frame(self, info->S,
412
self->slot,
413
FALSE,
414
discovery_rsp);
415
self->frame_sent = TRUE;
416
} else
417
self->frame_sent = FALSE;
418
419
/*
420
* Go to reply state until end of discovery to
421
* inhibit our own transmissions. Set the timer
422
* to not stay forever there... Jean II
423
*/
424
irlap_start_query_timer(self, info->S, info->s);
425
irlap_next_state(self, LAP_REPLY);
426
} else {
427
/* This is the final slot. How is it possible ?
428
* This would happen is both discoveries are just slightly
429
* offset (if they are in sync, all packets are lost).
430
* Most often, all the discovery requests will be received
431
* in QUERY state (see my comment there), except for the
432
* last frame that will come here.
433
* The big trouble when it happen is that active discovery
434
* doesn't happen, because nobody answer the discoveries
435
* frame of the other guy, so the log shows up empty.
436
* What should we do ?
437
* Not much. It's too late to answer those discovery frames,
438
* so we just pass the info to IrLMP who will put it in the
439
* log (and post an event).
440
* Another cause would be devices that do discovery much
441
* slower than us, however the latest fixes should minimise
442
* those cases...
443
* Jean II
444
*/
445
IRDA_DEBUG(1, "%s(), Receiving final discovery request, missed the discovery slots :-(\n", __func__);
446
447
/* Last discovery request -> in the log */
448
irlap_discovery_indication(self, info->discovery);
449
}
450
break;
451
case MEDIA_BUSY_TIMER_EXPIRED:
452
/* A bunch of events may be postponed because the media is
453
* busy (usually immediately after we close a connection),
454
* or while we are doing discovery (state query/reply).
455
* In all those cases, the media busy flag will be cleared
456
* when it's OK for us to process those postponed events.
457
* This event is not mentioned in the state machines in the
458
* IrLAP spec. It's because they didn't consider Ultra and
459
* postponing connection request is optional.
460
* Jean II */
461
#ifdef CONFIG_IRDA_ULTRA
462
/* Send any pending Ultra frames if any */
463
if (!skb_queue_empty(&self->txq_ultra)) {
464
/* We don't send the frame, just post an event.
465
* Also, previously this code was in timer.c...
466
* Jean II */
467
ret = (*state[self->state])(self, SEND_UI_FRAME,
468
NULL, NULL);
469
}
470
#endif /* CONFIG_IRDA_ULTRA */
471
/* Check if we should try to connect.
472
* This code was previously in irlap_do_event() */
473
if (self->connect_pending) {
474
self->connect_pending = FALSE;
475
476
/* This one *should* not pend in this state, except
477
* if a socket try to connect and immediately
478
* disconnect. - clear - Jean II */
479
if (self->disconnect_pending)
480
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
481
else
482
ret = (*state[self->state])(self,
483
CONNECT_REQUEST,
484
NULL, NULL);
485
self->disconnect_pending = FALSE;
486
}
487
/* Note : one way to test if this code works well (including
488
* media busy and small busy) is to create a user space
489
* application generating an Ultra packet every 3.05 sec (or
490
* 2.95 sec) and to see how it interact with discovery.
491
* It's fairly easy to check that no packet is lost, that the
492
* packets are postponed during discovery and that after
493
* discovery indication you have a 100ms "gap".
494
* As connection request and Ultra are now processed the same
495
* way, this avoid the tedious job of trying IrLAP connection
496
* in all those cases...
497
* Jean II */
498
break;
499
#ifdef CONFIG_IRDA_ULTRA
500
case SEND_UI_FRAME:
501
{
502
int i;
503
/* Only allowed to repeat an operation twice */
504
for (i=0; ((i<2) && (self->media_busy == FALSE)); i++) {
505
skb = skb_dequeue(&self->txq_ultra);
506
if (skb)
507
irlap_send_ui_frame(self, skb, CBROADCAST,
508
CMD_FRAME);
509
else
510
break;
511
/* irlap_send_ui_frame() won't increase skb reference
512
* count, so no dev_kfree_skb() - Jean II */
513
}
514
if (i == 2) {
515
/* Force us to listen 500 ms again */
516
irda_device_set_media_busy(self->netdev, TRUE);
517
}
518
break;
519
}
520
case RECV_UI_FRAME:
521
/* Only accept broadcast frames in NDM mode */
522
if (info->caddr != CBROADCAST) {
523
IRDA_DEBUG(0, "%s(), not a broadcast frame!\n",
524
__func__);
525
} else
526
irlap_unitdata_indication(self, skb);
527
break;
528
#endif /* CONFIG_IRDA_ULTRA */
529
case RECV_TEST_CMD:
530
/* Remove test frame header */
531
skb_pull(skb, sizeof(struct test_frame));
532
533
/*
534
* Send response. This skb will not be sent out again, and
535
* will only be used to send out the same info as the cmd
536
*/
537
irlap_send_test_frame(self, CBROADCAST, info->daddr, skb);
538
break;
539
case RECV_TEST_RSP:
540
IRDA_DEBUG(0, "%s() not implemented!\n", __func__);
541
break;
542
default:
543
IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
544
irlap_event[event]);
545
546
ret = -1;
547
break;
548
}
549
return ret;
550
}
551
552
/*
553
* Function irlap_state_query (event, skb, info)
554
*
555
* QUERY state
556
*
557
*/
558
static int irlap_state_query(struct irlap_cb *self, IRLAP_EVENT event,
559
struct sk_buff *skb, struct irlap_info *info)
560
{
561
int ret = 0;
562
563
IRDA_ASSERT(self != NULL, return -1;);
564
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
565
566
switch (event) {
567
case RECV_DISCOVERY_XID_RSP:
568
IRDA_ASSERT(info != NULL, return -1;);
569
IRDA_ASSERT(info->discovery != NULL, return -1;);
570
571
IRDA_DEBUG(4, "%s(), daddr=%08x\n", __func__,
572
info->discovery->data.daddr);
573
574
if (!self->discovery_log) {
575
IRDA_WARNING("%s: discovery log is gone! "
576
"maybe the discovery timeout has been set"
577
" too short?\n", __func__);
578
break;
579
}
580
hashbin_insert(self->discovery_log,
581
(irda_queue_t *) info->discovery,
582
info->discovery->data.daddr, NULL);
583
584
/* Keep state */
585
/* irlap_next_state(self, LAP_QUERY); */
586
587
break;
588
case RECV_DISCOVERY_XID_CMD:
589
/* Yes, it is possible to receive those frames in this mode.
590
* Note that most often the last discovery request won't
591
* occur here but in NDM state (see my comment there).
592
* What should we do ?
593
* Not much. We are currently performing our own discovery,
594
* therefore we can't answer those frames. We don't want
595
* to change state either. We just pass the info to
596
* IrLMP who will put it in the log (and post an event).
597
* Jean II
598
*/
599
600
IRDA_ASSERT(info != NULL, return -1;);
601
602
IRDA_DEBUG(1, "%s(), Receiving discovery request (s = %d) while performing discovery :-(\n", __func__, info->s);
603
604
/* Last discovery request ? */
605
if (info->s == 0xff)
606
irlap_discovery_indication(self, info->discovery);
607
break;
608
case SLOT_TIMER_EXPIRED:
609
/*
610
* Wait a little longer if we detect an incoming frame. This
611
* is not mentioned in the spec, but is a good thing to do,
612
* since we want to work even with devices that violate the
613
* timing requirements.
614
*/
615
if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
616
IRDA_DEBUG(2, "%s(), device is slow to answer, "
617
"waiting some more!\n", __func__);
618
irlap_start_slot_timer(self, msecs_to_jiffies(10));
619
self->add_wait = TRUE;
620
return ret;
621
}
622
self->add_wait = FALSE;
623
624
if (self->s < self->S) {
625
irlap_send_discovery_xid_frame(self, self->S,
626
self->s, TRUE,
627
self->discovery_cmd);
628
self->s++;
629
irlap_start_slot_timer(self, self->slot_timeout);
630
631
/* Keep state */
632
irlap_next_state(self, LAP_QUERY);
633
} else {
634
/* This is the final slot! */
635
irlap_send_discovery_xid_frame(self, self->S, 0xff,
636
TRUE,
637
self->discovery_cmd);
638
639
/* Always switch state before calling upper layers */
640
irlap_next_state(self, LAP_NDM);
641
642
/*
643
* We are now finished with the discovery procedure,
644
* so now we must return the results
645
*/
646
irlap_discovery_confirm(self, self->discovery_log);
647
648
/* IrLMP should now have taken care of the log */
649
self->discovery_log = NULL;
650
}
651
break;
652
default:
653
IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
654
irlap_event[event]);
655
656
ret = -1;
657
break;
658
}
659
return ret;
660
}
661
662
/*
663
* Function irlap_state_reply (self, event, skb, info)
664
*
665
* REPLY, we have received a XID discovery frame from a device and we
666
* are waiting for the right time slot to send a response XID frame
667
*
668
*/
669
static int irlap_state_reply(struct irlap_cb *self, IRLAP_EVENT event,
670
struct sk_buff *skb, struct irlap_info *info)
671
{
672
discovery_t *discovery_rsp;
673
int ret=0;
674
675
IRDA_DEBUG(4, "%s()\n", __func__);
676
677
IRDA_ASSERT(self != NULL, return -1;);
678
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
679
680
switch (event) {
681
case QUERY_TIMER_EXPIRED:
682
IRDA_DEBUG(0, "%s(), QUERY_TIMER_EXPIRED <%ld>\n",
683
__func__, jiffies);
684
irlap_next_state(self, LAP_NDM);
685
break;
686
case RECV_DISCOVERY_XID_CMD:
687
IRDA_ASSERT(info != NULL, return -1;);
688
/* Last frame? */
689
if (info->s == 0xff) {
690
del_timer(&self->query_timer);
691
692
/* info->log.condition = REMOTE; */
693
694
/* Always switch state before calling upper layers */
695
irlap_next_state(self, LAP_NDM);
696
697
irlap_discovery_indication(self, info->discovery);
698
} else {
699
/* If it's our slot, send our reply */
700
if ((info->s >= self->slot) && (!self->frame_sent)) {
701
discovery_rsp = irlmp_get_discovery_response();
702
discovery_rsp->data.daddr = info->daddr;
703
704
irlap_send_discovery_xid_frame(self, info->S,
705
self->slot,
706
FALSE,
707
discovery_rsp);
708
709
self->frame_sent = TRUE;
710
}
711
/* Readjust our timer to accommodate devices
712
* doing faster or slower discovery than us...
713
* Jean II */
714
irlap_start_query_timer(self, info->S, info->s);
715
716
/* Keep state */
717
//irlap_next_state(self, LAP_REPLY);
718
}
719
break;
720
default:
721
IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __func__,
722
event, irlap_event[event]);
723
724
ret = -1;
725
break;
726
}
727
return ret;
728
}
729
730
/*
731
* Function irlap_state_conn (event, skb, info)
732
*
733
* CONN, we have received a SNRM command and is waiting for the upper
734
* layer to accept or refuse connection
735
*
736
*/
737
static int irlap_state_conn(struct irlap_cb *self, IRLAP_EVENT event,
738
struct sk_buff *skb, struct irlap_info *info)
739
{
740
int ret = 0;
741
742
IRDA_DEBUG(4, "%s(), event=%s\n", __func__, irlap_event[ event]);
743
744
IRDA_ASSERT(self != NULL, return -1;);
745
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
746
747
switch (event) {
748
case CONNECT_RESPONSE:
749
skb_pull(skb, sizeof(struct snrm_frame));
750
751
IRDA_ASSERT(self->netdev != NULL, return -1;);
752
753
irlap_qos_negotiate(self, skb);
754
755
irlap_initiate_connection_state(self);
756
757
/*
758
* Applying the parameters now will make sure we change speed
759
* *after* we have sent the next frame
760
*/
761
irlap_apply_connection_parameters(self, FALSE);
762
763
/*
764
* Sending this frame will force a speed change after it has
765
* been sent (i.e. the frame will be sent at 9600).
766
*/
767
irlap_send_ua_response_frame(self, &self->qos_rx);
768
769
#if 0
770
/*
771
* We are allowed to send two frames, but this may increase
772
* the connect latency, so lets not do it for now.
773
*/
774
/* This is full of good intentions, but doesn't work in
775
* practice.
776
* After sending the first UA response, we switch the
777
* dongle to the negotiated speed, which is usually
778
* different than 9600 kb/s.
779
* From there, there is two solutions :
780
* 1) The other end has received the first UA response :
781
* it will set up the connection, move to state LAP_NRM_P,
782
* and will ignore and drop the second UA response.
783
* Actually, it's even worse : the other side will almost
784
* immediately send a RR that will likely collide with the
785
* UA response (depending on negotiated turnaround).
786
* 2) The other end has not received the first UA response,
787
* will stay at 9600 and will never see the second UA response.
788
* Jean II */
789
irlap_send_ua_response_frame(self, &self->qos_rx);
790
#endif
791
792
/*
793
* The WD-timer could be set to the duration of the P-timer
794
* for this case, but it is recommended to use twice the
795
* value (note 3 IrLAP p. 60).
796
*/
797
irlap_start_wd_timer(self, self->wd_timeout);
798
irlap_next_state(self, LAP_NRM_S);
799
800
break;
801
case RECV_DISCOVERY_XID_CMD:
802
IRDA_DEBUG(3, "%s(), event RECV_DISCOVER_XID_CMD!\n",
803
__func__);
804
irlap_next_state(self, LAP_NDM);
805
806
break;
807
case DISCONNECT_REQUEST:
808
IRDA_DEBUG(0, "%s(), Disconnect request!\n", __func__);
809
irlap_send_dm_frame(self);
810
irlap_next_state( self, LAP_NDM);
811
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
812
break;
813
default:
814
IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __func__,
815
event, irlap_event[event]);
816
817
ret = -1;
818
break;
819
}
820
821
return ret;
822
}
823
824
/*
825
* Function irlap_state_setup (event, skb, frame)
826
*
827
* SETUP state, The local layer has transmitted a SNRM command frame to
828
* a remote peer layer and is awaiting a reply .
829
*
830
*/
831
static int irlap_state_setup(struct irlap_cb *self, IRLAP_EVENT event,
832
struct sk_buff *skb, struct irlap_info *info)
833
{
834
int ret = 0;
835
836
IRDA_DEBUG(4, "%s()\n", __func__);
837
838
IRDA_ASSERT(self != NULL, return -1;);
839
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
840
841
switch (event) {
842
case FINAL_TIMER_EXPIRED:
843
if (self->retry_count < self->N3) {
844
/*
845
* Perform random backoff, Wait a random number of time units, minimum
846
* duration half the time taken to transmitt a SNRM frame, maximum duration
847
* 1.5 times the time taken to transmit a SNRM frame. So this time should
848
* between 15 msecs and 45 msecs.
849
*/
850
irlap_start_backoff_timer(self, msecs_to_jiffies(20 +
851
(jiffies % 30)));
852
} else {
853
/* Always switch state before calling upper layers */
854
irlap_next_state(self, LAP_NDM);
855
856
irlap_disconnect_indication(self, LAP_FOUND_NONE);
857
}
858
break;
859
case BACKOFF_TIMER_EXPIRED:
860
irlap_send_snrm_frame(self, &self->qos_rx);
861
irlap_start_final_timer(self, self->final_timeout);
862
self->retry_count++;
863
break;
864
case RECV_SNRM_CMD:
865
IRDA_DEBUG(4, "%s(), SNRM battle!\n", __func__);
866
867
IRDA_ASSERT(skb != NULL, return 0;);
868
IRDA_ASSERT(info != NULL, return 0;);
869
870
/*
871
* The device with the largest device address wins the battle
872
* (both have sent a SNRM command!)
873
*/
874
if (info &&(info->daddr > self->saddr)) {
875
del_timer(&self->final_timer);
876
irlap_initiate_connection_state(self);
877
878
IRDA_ASSERT(self->netdev != NULL, return -1;);
879
880
skb_pull(skb, sizeof(struct snrm_frame));
881
882
irlap_qos_negotiate(self, skb);
883
884
/* Send UA frame and then change link settings */
885
irlap_apply_connection_parameters(self, FALSE);
886
irlap_send_ua_response_frame(self, &self->qos_rx);
887
888
irlap_next_state(self, LAP_NRM_S);
889
irlap_connect_confirm(self, skb);
890
891
/*
892
* The WD-timer could be set to the duration of the
893
* P-timer for this case, but it is recommended
894
* to use twice the value (note 3 IrLAP p. 60).
895
*/
896
irlap_start_wd_timer(self, self->wd_timeout);
897
} else {
898
/* We just ignore the other device! */
899
irlap_next_state(self, LAP_SETUP);
900
}
901
break;
902
case RECV_UA_RSP:
903
/* Stop F-timer */
904
del_timer(&self->final_timer);
905
906
/* Initiate connection state */
907
irlap_initiate_connection_state(self);
908
909
/* Negotiate connection parameters */
910
IRDA_ASSERT(skb->len > 10, return -1;);
911
912
skb_pull(skb, sizeof(struct ua_frame));
913
914
IRDA_ASSERT(self->netdev != NULL, return -1;);
915
916
irlap_qos_negotiate(self, skb);
917
918
/* Set the new link setting *now* (before the rr frame) */
919
irlap_apply_connection_parameters(self, TRUE);
920
self->retry_count = 0;
921
922
/* Wait for turnaround time to give a chance to the other
923
* device to be ready to receive us.
924
* Note : the time to switch speed is typically larger
925
* than the turnaround time, but as we don't have the other
926
* side speed switch time, that's our best guess...
927
* Jean II */
928
irlap_wait_min_turn_around(self, &self->qos_tx);
929
930
/* This frame will actually be sent at the new speed */
931
irlap_send_rr_frame(self, CMD_FRAME);
932
933
/* The timer is set to half the normal timer to quickly
934
* detect a failure to negotiate the new connection
935
* parameters. IrLAP 6.11.3.2, note 3.
936
* Note that currently we don't process this failure
937
* properly, as we should do a quick disconnect.
938
* Jean II */
939
irlap_start_final_timer(self, self->final_timeout/2);
940
irlap_next_state(self, LAP_NRM_P);
941
942
irlap_connect_confirm(self, skb);
943
break;
944
case RECV_DM_RSP: /* FALLTHROUGH */
945
case RECV_DISC_CMD:
946
del_timer(&self->final_timer);
947
irlap_next_state(self, LAP_NDM);
948
949
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
950
break;
951
default:
952
IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __func__,
953
event, irlap_event[event]);
954
955
ret = -1;
956
break;
957
}
958
return ret;
959
}
960
961
/*
962
* Function irlap_state_offline (self, event, skb, info)
963
*
964
* OFFLINE state, not used for now!
965
*
966
*/
967
static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
968
struct sk_buff *skb, struct irlap_info *info)
969
{
970
IRDA_DEBUG( 0, "%s(), Unknown event\n", __func__);
971
972
return -1;
973
}
974
975
/*
976
* Function irlap_state_xmit_p (self, event, skb, info)
977
*
978
* XMIT, Only the primary station has right to transmit, and we
979
* therefore do not expect to receive any transmissions from other
980
* stations.
981
*
982
*/
983
static int irlap_state_xmit_p(struct irlap_cb *self, IRLAP_EVENT event,
984
struct sk_buff *skb, struct irlap_info *info)
985
{
986
int ret = 0;
987
988
switch (event) {
989
case SEND_I_CMD:
990
/*
991
* Only send frame if send-window > 0.
992
*/
993
if ((self->window > 0) && (!self->remote_busy)) {
994
int nextfit;
995
#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
996
struct sk_buff *skb_next;
997
998
/* With DYNAMIC_WINDOW, we keep the window size
999
* maximum, and adapt on the packets we are sending.
1000
* At 115k, we can send only 2 packets of 2048 bytes
1001
* in a 500 ms turnaround. Without this option, we
1002
* would always limit the window to 2. With this
1003
* option, if we send smaller packets, we can send
1004
* up to 7 of them (always depending on QoS).
1005
* Jean II */
1006
1007
/* Look at the next skb. This is safe, as we are
1008
* the only consumer of the Tx queue (if we are not,
1009
* we have other problems) - Jean II */
1010
skb_next = skb_peek(&self->txq);
1011
1012
/* Check if a subsequent skb exist and would fit in
1013
* the current window (with respect to turnaround
1014
* time).
1015
* This allow us to properly mark the current packet
1016
* with the pf bit, to avoid falling back on the
1017
* second test below, and avoid waiting the
1018
* end of the window and sending a extra RR.
1019
* Note : (skb_next != NULL) <=> (skb_queue_len() > 0)
1020
* Jean II */
1021
nextfit = ((skb_next != NULL) &&
1022
((skb_next->len + skb->len) <=
1023
self->bytes_left));
1024
1025
/*
1026
* The current packet may not fit ! Because of test
1027
* above, this should not happen any more !!!
1028
* Test if we have transmitted more bytes over the
1029
* link than its possible to do with the current
1030
* speed and turn-around-time.
1031
*/
1032
if((!nextfit) && (skb->len > self->bytes_left)) {
1033
IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1034
" more bytes!\n", __func__);
1035
/* Requeue the skb */
1036
skb_queue_head(&self->txq, skb_get(skb));
1037
/*
1038
* We should switch state to LAP_NRM_P, but
1039
* that is not possible since we must be sure
1040
* that we poll the other side. Since we have
1041
* used up our time, the poll timer should
1042
* trigger anyway now, so we just wait for it
1043
* DB
1044
*/
1045
/*
1046
* Sorry, but that's not totally true. If
1047
* we send 2000B packets, we may wait another
1048
* 1000B until our turnaround expire. That's
1049
* why we need to be proactive in avoiding
1050
* coming here. - Jean II
1051
*/
1052
return -EPROTO;
1053
}
1054
1055
/* Subtract space used by this skb */
1056
self->bytes_left -= skb->len;
1057
#else /* CONFIG_IRDA_DYNAMIC_WINDOW */
1058
/* Window has been adjusted for the max packet
1059
* size, so much simpler... - Jean II */
1060
nextfit = !skb_queue_empty(&self->txq);
1061
#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1062
/*
1063
* Send data with poll bit cleared only if window > 1
1064
* and there is more frames after this one to be sent
1065
*/
1066
if ((self->window > 1) && (nextfit)) {
1067
/* More packet to send in current window */
1068
irlap_send_data_primary(self, skb);
1069
irlap_next_state(self, LAP_XMIT_P);
1070
} else {
1071
/* Final packet of window */
1072
irlap_send_data_primary_poll(self, skb);
1073
1074
/*
1075
* Make sure state machine does not try to send
1076
* any more frames
1077
*/
1078
ret = -EPROTO;
1079
}
1080
#ifdef CONFIG_IRDA_FAST_RR
1081
/* Peer may want to reply immediately */
1082
self->fast_RR = FALSE;
1083
#endif /* CONFIG_IRDA_FAST_RR */
1084
} else {
1085
IRDA_DEBUG(4, "%s(), Unable to send! remote busy?\n",
1086
__func__);
1087
skb_queue_head(&self->txq, skb_get(skb));
1088
1089
/*
1090
* The next ret is important, because it tells
1091
* irlap_next_state _not_ to deliver more frames
1092
*/
1093
ret = -EPROTO;
1094
}
1095
break;
1096
case POLL_TIMER_EXPIRED:
1097
IRDA_DEBUG(3, "%s(), POLL_TIMER_EXPIRED <%ld>\n",
1098
__func__, jiffies);
1099
irlap_send_rr_frame(self, CMD_FRAME);
1100
/* Return to NRM properly - Jean II */
1101
self->window = self->window_size;
1102
#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1103
/* Allowed to transmit a maximum number of bytes again. */
1104
self->bytes_left = self->line_capacity;
1105
#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1106
irlap_start_final_timer(self, self->final_timeout);
1107
irlap_next_state(self, LAP_NRM_P);
1108
break;
1109
case DISCONNECT_REQUEST:
1110
del_timer(&self->poll_timer);
1111
irlap_wait_min_turn_around(self, &self->qos_tx);
1112
irlap_send_disc_frame(self);
1113
irlap_flush_all_queues(self);
1114
irlap_start_final_timer(self, self->final_timeout);
1115
self->retry_count = 0;
1116
irlap_next_state(self, LAP_PCLOSE);
1117
break;
1118
case DATA_REQUEST:
1119
/* Nothing to do, irlap_do_event() will send the packet
1120
* when we return... - Jean II */
1121
break;
1122
default:
1123
IRDA_DEBUG(0, "%s(), Unknown event %s\n",
1124
__func__, irlap_event[event]);
1125
1126
ret = -EINVAL;
1127
break;
1128
}
1129
return ret;
1130
}
1131
1132
/*
1133
* Function irlap_state_pclose (event, skb, info)
1134
*
1135
* PCLOSE state
1136
*/
1137
static int irlap_state_pclose(struct irlap_cb *self, IRLAP_EVENT event,
1138
struct sk_buff *skb, struct irlap_info *info)
1139
{
1140
int ret = 0;
1141
1142
IRDA_DEBUG(1, "%s()\n", __func__);
1143
1144
IRDA_ASSERT(self != NULL, return -1;);
1145
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1146
1147
switch (event) {
1148
case RECV_UA_RSP: /* FALLTHROUGH */
1149
case RECV_DM_RSP:
1150
del_timer(&self->final_timer);
1151
1152
/* Set new link parameters */
1153
irlap_apply_default_connection_parameters(self);
1154
1155
/* Always switch state before calling upper layers */
1156
irlap_next_state(self, LAP_NDM);
1157
1158
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
1159
break;
1160
case FINAL_TIMER_EXPIRED:
1161
if (self->retry_count < self->N3) {
1162
irlap_wait_min_turn_around(self, &self->qos_tx);
1163
irlap_send_disc_frame(self);
1164
irlap_start_final_timer(self, self->final_timeout);
1165
self->retry_count++;
1166
/* Keep state */
1167
} else {
1168
irlap_apply_default_connection_parameters(self);
1169
1170
/* Always switch state before calling upper layers */
1171
irlap_next_state(self, LAP_NDM);
1172
1173
irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1174
}
1175
break;
1176
default:
1177
IRDA_DEBUG(1, "%s(), Unknown event %d\n", __func__, event);
1178
1179
ret = -1;
1180
break;
1181
}
1182
return ret;
1183
}
1184
1185
/*
1186
* Function irlap_state_nrm_p (self, event, skb, info)
1187
*
1188
* NRM_P (Normal Response Mode as Primary), The primary station has given
1189
* permissions to a secondary station to transmit IrLAP resonse frames
1190
* (by sending a frame with the P bit set). The primary station will not
1191
* transmit any frames and is expecting to receive frames only from the
1192
* secondary to which transmission permissions has been given.
1193
*/
1194
static int irlap_state_nrm_p(struct irlap_cb *self, IRLAP_EVENT event,
1195
struct sk_buff *skb, struct irlap_info *info)
1196
{
1197
int ret = 0;
1198
int ns_status;
1199
int nr_status;
1200
1201
switch (event) {
1202
case RECV_I_RSP: /* Optimize for the common case */
1203
if (unlikely(skb->len <= LAP_ADDR_HEADER + LAP_CTRL_HEADER)) {
1204
/*
1205
* Input validation check: a stir4200/mcp2150
1206
* combination sometimes results in an empty i:rsp.
1207
* This makes no sense; we can just ignore the frame
1208
* and send an rr:cmd immediately. This happens before
1209
* changing nr or ns so triggers a retransmit
1210
*/
1211
irlap_wait_min_turn_around(self, &self->qos_tx);
1212
irlap_send_rr_frame(self, CMD_FRAME);
1213
/* Keep state */
1214
break;
1215
}
1216
/* FIXME: must check for remote_busy below */
1217
#ifdef CONFIG_IRDA_FAST_RR
1218
/*
1219
* Reset the fast_RR so we can use the fast RR code with
1220
* full speed the next time since peer may have more frames
1221
* to transmitt
1222
*/
1223
self->fast_RR = FALSE;
1224
#endif /* CONFIG_IRDA_FAST_RR */
1225
IRDA_ASSERT( info != NULL, return -1;);
1226
1227
ns_status = irlap_validate_ns_received(self, info->ns);
1228
nr_status = irlap_validate_nr_received(self, info->nr);
1229
1230
/*
1231
* Check for expected I(nformation) frame
1232
*/
1233
if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1234
1235
/* Update Vr (next frame for us to receive) */
1236
self->vr = (self->vr + 1) % 8;
1237
1238
/* Update Nr received, cleanup our retry queue */
1239
irlap_update_nr_received(self, info->nr);
1240
1241
/*
1242
* Got expected NR, so reset the
1243
* retry_count. This is not done by IrLAP spec,
1244
* which is strange!
1245
*/
1246
self->retry_count = 0;
1247
self->ack_required = TRUE;
1248
1249
/* poll bit cleared? */
1250
if (!info->pf) {
1251
/* Keep state, do not move this line */
1252
irlap_next_state(self, LAP_NRM_P);
1253
1254
irlap_data_indication(self, skb, FALSE);
1255
} else {
1256
/* No longer waiting for pf */
1257
del_timer(&self->final_timer);
1258
1259
irlap_wait_min_turn_around(self, &self->qos_tx);
1260
1261
/* Call higher layer *before* changing state
1262
* to give them a chance to send data in the
1263
* next LAP frame.
1264
* Jean II */
1265
irlap_data_indication(self, skb, FALSE);
1266
1267
/* XMIT states are the most dangerous state
1268
* to be in, because user requests are
1269
* processed directly and may change state.
1270
* On the other hand, in NDM_P, those
1271
* requests are queued and we will process
1272
* them when we return to irlap_do_event().
1273
* Jean II
1274
*/
1275
irlap_next_state(self, LAP_XMIT_P);
1276
1277
/* This is the last frame.
1278
* Make sure it's always called in XMIT state.
1279
* - Jean II */
1280
irlap_start_poll_timer(self, self->poll_timeout);
1281
}
1282
break;
1283
1284
}
1285
/* Unexpected next to send (Ns) */
1286
if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1287
{
1288
if (!info->pf) {
1289
irlap_update_nr_received(self, info->nr);
1290
1291
/*
1292
* Wait until the last frame before doing
1293
* anything
1294
*/
1295
1296
/* Keep state */
1297
irlap_next_state(self, LAP_NRM_P);
1298
} else {
1299
IRDA_DEBUG(4,
1300
"%s(), missing or duplicate frame!\n",
1301
__func__);
1302
1303
/* Update Nr received */
1304
irlap_update_nr_received(self, info->nr);
1305
1306
irlap_wait_min_turn_around(self, &self->qos_tx);
1307
irlap_send_rr_frame(self, CMD_FRAME);
1308
1309
self->ack_required = FALSE;
1310
1311
irlap_start_final_timer(self, self->final_timeout);
1312
irlap_next_state(self, LAP_NRM_P);
1313
}
1314
break;
1315
}
1316
/*
1317
* Unexpected next to receive (Nr)
1318
*/
1319
if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1320
{
1321
if (info->pf) {
1322
self->vr = (self->vr + 1) % 8;
1323
1324
/* Update Nr received */
1325
irlap_update_nr_received(self, info->nr);
1326
1327
/* Resend rejected frames */
1328
irlap_resend_rejected_frames(self, CMD_FRAME);
1329
1330
self->ack_required = FALSE;
1331
1332
/* Make sure we account for the time
1333
* to transmit our frames. See comemnts
1334
* in irlap_send_data_primary_poll().
1335
* Jean II */
1336
irlap_start_final_timer(self, 2 * self->final_timeout);
1337
1338
/* Keep state, do not move this line */
1339
irlap_next_state(self, LAP_NRM_P);
1340
1341
irlap_data_indication(self, skb, FALSE);
1342
} else {
1343
/*
1344
* Do not resend frames until the last
1345
* frame has arrived from the other
1346
* device. This is not documented in
1347
* IrLAP!!
1348
*/
1349
self->vr = (self->vr + 1) % 8;
1350
1351
/* Update Nr received */
1352
irlap_update_nr_received(self, info->nr);
1353
1354
self->ack_required = FALSE;
1355
1356
/* Keep state, do not move this line!*/
1357
irlap_next_state(self, LAP_NRM_P);
1358
1359
irlap_data_indication(self, skb, FALSE);
1360
}
1361
break;
1362
}
1363
/*
1364
* Unexpected next to send (Ns) and next to receive (Nr)
1365
* Not documented by IrLAP!
1366
*/
1367
if ((ns_status == NS_UNEXPECTED) &&
1368
(nr_status == NR_UNEXPECTED))
1369
{
1370
IRDA_DEBUG(4, "%s(), unexpected nr and ns!\n",
1371
__func__);
1372
if (info->pf) {
1373
/* Resend rejected frames */
1374
irlap_resend_rejected_frames(self, CMD_FRAME);
1375
1376
/* Give peer some time to retransmit!
1377
* But account for our own Tx. */
1378
irlap_start_final_timer(self, 2 * self->final_timeout);
1379
1380
/* Keep state, do not move this line */
1381
irlap_next_state(self, LAP_NRM_P);
1382
} else {
1383
/* Update Nr received */
1384
/* irlap_update_nr_received( info->nr); */
1385
1386
self->ack_required = FALSE;
1387
}
1388
break;
1389
}
1390
1391
/*
1392
* Invalid NR or NS
1393
*/
1394
if ((nr_status == NR_INVALID) || (ns_status == NS_INVALID)) {
1395
if (info->pf) {
1396
del_timer(&self->final_timer);
1397
1398
irlap_next_state(self, LAP_RESET_WAIT);
1399
1400
irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1401
self->xmitflag = TRUE;
1402
} else {
1403
del_timer(&self->final_timer);
1404
1405
irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1406
1407
self->xmitflag = FALSE;
1408
}
1409
break;
1410
}
1411
IRDA_DEBUG(1, "%s(), Not implemented!\n", __func__);
1412
IRDA_DEBUG(1, "%s(), event=%s, ns_status=%d, nr_status=%d\n",
1413
__func__, irlap_event[event], ns_status, nr_status);
1414
break;
1415
case RECV_UI_FRAME:
1416
/* Poll bit cleared? */
1417
if (!info->pf) {
1418
irlap_data_indication(self, skb, TRUE);
1419
irlap_next_state(self, LAP_NRM_P);
1420
} else {
1421
del_timer(&self->final_timer);
1422
irlap_data_indication(self, skb, TRUE);
1423
irlap_next_state(self, LAP_XMIT_P);
1424
IRDA_DEBUG(1, "%s: RECV_UI_FRAME: next state %s\n", __func__, irlap_state[self->state]);
1425
irlap_start_poll_timer(self, self->poll_timeout);
1426
}
1427
break;
1428
case RECV_RR_RSP:
1429
/*
1430
* If you get a RR, the remote isn't busy anymore,
1431
* no matter what the NR
1432
*/
1433
self->remote_busy = FALSE;
1434
1435
/* Stop final timer */
1436
del_timer(&self->final_timer);
1437
1438
/*
1439
* Nr as expected?
1440
*/
1441
ret = irlap_validate_nr_received(self, info->nr);
1442
if (ret == NR_EXPECTED) {
1443
/* Update Nr received */
1444
irlap_update_nr_received(self, info->nr);
1445
1446
/*
1447
* Got expected NR, so reset the retry_count. This
1448
* is not done by the IrLAP standard , which is
1449
* strange! DB.
1450
*/
1451
self->retry_count = 0;
1452
irlap_wait_min_turn_around(self, &self->qos_tx);
1453
1454
irlap_next_state(self, LAP_XMIT_P);
1455
1456
/* Start poll timer */
1457
irlap_start_poll_timer(self, self->poll_timeout);
1458
} else if (ret == NR_UNEXPECTED) {
1459
IRDA_ASSERT(info != NULL, return -1;);
1460
/*
1461
* Unexpected nr!
1462
*/
1463
1464
/* Update Nr received */
1465
irlap_update_nr_received(self, info->nr);
1466
1467
IRDA_DEBUG(4, "RECV_RR_FRAME: Retrans:%d, nr=%d, va=%d, "
1468
"vs=%d, vr=%d\n",
1469
self->retry_count, info->nr, self->va,
1470
self->vs, self->vr);
1471
1472
/* Resend rejected frames */
1473
irlap_resend_rejected_frames(self, CMD_FRAME);
1474
irlap_start_final_timer(self, self->final_timeout * 2);
1475
1476
irlap_next_state(self, LAP_NRM_P);
1477
} else if (ret == NR_INVALID) {
1478
IRDA_DEBUG(1, "%s(), Received RR with "
1479
"invalid nr !\n", __func__);
1480
1481
irlap_next_state(self, LAP_RESET_WAIT);
1482
1483
irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1484
self->xmitflag = TRUE;
1485
}
1486
break;
1487
case RECV_RNR_RSP:
1488
IRDA_ASSERT(info != NULL, return -1;);
1489
1490
/* Stop final timer */
1491
del_timer(&self->final_timer);
1492
self->remote_busy = TRUE;
1493
1494
/* Update Nr received */
1495
irlap_update_nr_received(self, info->nr);
1496
irlap_next_state(self, LAP_XMIT_P);
1497
1498
/* Start poll timer */
1499
irlap_start_poll_timer(self, self->poll_timeout);
1500
break;
1501
case RECV_FRMR_RSP:
1502
del_timer(&self->final_timer);
1503
self->xmitflag = TRUE;
1504
irlap_next_state(self, LAP_RESET_WAIT);
1505
irlap_reset_indication(self);
1506
break;
1507
case FINAL_TIMER_EXPIRED:
1508
/*
1509
* We are allowed to wait for additional 300 ms if
1510
* final timer expires when we are in the middle
1511
* of receiving a frame (page 45, IrLAP). Check that
1512
* we only do this once for each frame.
1513
*/
1514
if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
1515
IRDA_DEBUG(1, "FINAL_TIMER_EXPIRED when receiving a "
1516
"frame! Waiting a little bit more!\n");
1517
irlap_start_final_timer(self, msecs_to_jiffies(300));
1518
1519
/*
1520
* Don't allow this to happen one more time in a row,
1521
* or else we can get a pretty tight loop here if
1522
* if we only receive half a frame. DB.
1523
*/
1524
self->add_wait = TRUE;
1525
break;
1526
}
1527
self->add_wait = FALSE;
1528
1529
/* N2 is the disconnect timer. Until we reach it, we retry */
1530
if (self->retry_count < self->N2) {
1531
if (skb_peek(&self->wx_list) == NULL) {
1532
/* Retry sending the pf bit to the secondary */
1533
IRDA_DEBUG(4, "nrm_p: resending rr");
1534
irlap_wait_min_turn_around(self, &self->qos_tx);
1535
irlap_send_rr_frame(self, CMD_FRAME);
1536
} else {
1537
IRDA_DEBUG(4, "nrm_p: resend frames");
1538
irlap_resend_rejected_frames(self, CMD_FRAME);
1539
}
1540
1541
irlap_start_final_timer(self, self->final_timeout);
1542
self->retry_count++;
1543
IRDA_DEBUG(4, "irlap_state_nrm_p: FINAL_TIMER_EXPIRED:"
1544
" retry_count=%d\n", self->retry_count);
1545
1546
/* Early warning event. I'm using a pretty liberal
1547
* interpretation of the spec and generate an event
1548
* every time the timer is multiple of N1 (and not
1549
* only the first time). This allow application
1550
* to know precisely if connectivity restart...
1551
* Jean II */
1552
if((self->retry_count % self->N1) == 0)
1553
irlap_status_indication(self,
1554
STATUS_NO_ACTIVITY);
1555
1556
/* Keep state */
1557
} else {
1558
irlap_apply_default_connection_parameters(self);
1559
1560
/* Always switch state before calling upper layers */
1561
irlap_next_state(self, LAP_NDM);
1562
irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1563
}
1564
break;
1565
case RECV_REJ_RSP:
1566
irlap_update_nr_received(self, info->nr);
1567
if (self->remote_busy) {
1568
irlap_wait_min_turn_around(self, &self->qos_tx);
1569
irlap_send_rr_frame(self, CMD_FRAME);
1570
} else
1571
irlap_resend_rejected_frames(self, CMD_FRAME);
1572
irlap_start_final_timer(self, 2 * self->final_timeout);
1573
break;
1574
case RECV_SREJ_RSP:
1575
irlap_update_nr_received(self, info->nr);
1576
if (self->remote_busy) {
1577
irlap_wait_min_turn_around(self, &self->qos_tx);
1578
irlap_send_rr_frame(self, CMD_FRAME);
1579
} else
1580
irlap_resend_rejected_frame(self, CMD_FRAME);
1581
irlap_start_final_timer(self, 2 * self->final_timeout);
1582
break;
1583
case RECV_RD_RSP:
1584
IRDA_DEBUG(1, "%s(), RECV_RD_RSP\n", __func__);
1585
1586
irlap_flush_all_queues(self);
1587
irlap_next_state(self, LAP_XMIT_P);
1588
/* Call back the LAP state machine to do a proper disconnect */
1589
irlap_disconnect_request(self);
1590
break;
1591
default:
1592
IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1593
__func__, irlap_event[event]);
1594
1595
ret = -1;
1596
break;
1597
}
1598
return ret;
1599
}
1600
1601
/*
1602
* Function irlap_state_reset_wait (event, skb, info)
1603
*
1604
* We have informed the service user of a reset condition, and is
1605
* awaiting reset of disconnect request.
1606
*
1607
*/
1608
static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
1609
struct sk_buff *skb, struct irlap_info *info)
1610
{
1611
int ret = 0;
1612
1613
IRDA_DEBUG(3, "%s(), event = %s\n", __func__, irlap_event[event]);
1614
1615
IRDA_ASSERT(self != NULL, return -1;);
1616
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1617
1618
switch (event) {
1619
case RESET_REQUEST:
1620
if (self->xmitflag) {
1621
irlap_wait_min_turn_around(self, &self->qos_tx);
1622
irlap_send_snrm_frame(self, NULL);
1623
irlap_start_final_timer(self, self->final_timeout);
1624
irlap_next_state(self, LAP_RESET);
1625
} else {
1626
irlap_start_final_timer(self, self->final_timeout);
1627
irlap_next_state(self, LAP_RESET);
1628
}
1629
break;
1630
case DISCONNECT_REQUEST:
1631
irlap_wait_min_turn_around( self, &self->qos_tx);
1632
irlap_send_disc_frame( self);
1633
irlap_flush_all_queues( self);
1634
irlap_start_final_timer( self, self->final_timeout);
1635
self->retry_count = 0;
1636
irlap_next_state( self, LAP_PCLOSE);
1637
break;
1638
default:
1639
IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
1640
irlap_event[event]);
1641
1642
ret = -1;
1643
break;
1644
}
1645
return ret;
1646
}
1647
1648
/*
1649
* Function irlap_state_reset (self, event, skb, info)
1650
*
1651
* We have sent a SNRM reset command to the peer layer, and is awaiting
1652
* reply.
1653
*
1654
*/
1655
static int irlap_state_reset(struct irlap_cb *self, IRLAP_EVENT event,
1656
struct sk_buff *skb, struct irlap_info *info)
1657
{
1658
int ret = 0;
1659
1660
IRDA_DEBUG(3, "%s(), event = %s\n", __func__, irlap_event[event]);
1661
1662
IRDA_ASSERT(self != NULL, return -1;);
1663
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1664
1665
switch (event) {
1666
case RECV_DISC_CMD:
1667
del_timer(&self->final_timer);
1668
1669
irlap_apply_default_connection_parameters(self);
1670
1671
/* Always switch state before calling upper layers */
1672
irlap_next_state(self, LAP_NDM);
1673
1674
irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1675
1676
break;
1677
case RECV_UA_RSP:
1678
del_timer(&self->final_timer);
1679
1680
/* Initiate connection state */
1681
irlap_initiate_connection_state(self);
1682
1683
irlap_reset_confirm();
1684
1685
self->remote_busy = FALSE;
1686
1687
irlap_next_state(self, LAP_XMIT_P);
1688
1689
irlap_start_poll_timer(self, self->poll_timeout);
1690
1691
break;
1692
case FINAL_TIMER_EXPIRED:
1693
if (self->retry_count < 3) {
1694
irlap_wait_min_turn_around(self, &self->qos_tx);
1695
1696
IRDA_ASSERT(self->netdev != NULL, return -1;);
1697
irlap_send_snrm_frame(self, self->qos_dev);
1698
1699
self->retry_count++; /* Experimental!! */
1700
1701
irlap_start_final_timer(self, self->final_timeout);
1702
irlap_next_state(self, LAP_RESET);
1703
} else if (self->retry_count >= self->N3) {
1704
irlap_apply_default_connection_parameters(self);
1705
1706
/* Always switch state before calling upper layers */
1707
irlap_next_state(self, LAP_NDM);
1708
1709
irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1710
}
1711
break;
1712
case RECV_SNRM_CMD:
1713
/*
1714
* SNRM frame is not allowed to contain an I-field in this
1715
* state
1716
*/
1717
if (!info) {
1718
IRDA_DEBUG(3, "%s(), RECV_SNRM_CMD\n", __func__);
1719
irlap_initiate_connection_state(self);
1720
irlap_wait_min_turn_around(self, &self->qos_tx);
1721
irlap_send_ua_response_frame(self, &self->qos_rx);
1722
irlap_reset_confirm();
1723
irlap_start_wd_timer(self, self->wd_timeout);
1724
irlap_next_state(self, LAP_NDM);
1725
} else {
1726
IRDA_DEBUG(0,
1727
"%s(), SNRM frame contained an I field!\n",
1728
__func__);
1729
}
1730
break;
1731
default:
1732
IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1733
__func__, irlap_event[event]);
1734
1735
ret = -1;
1736
break;
1737
}
1738
return ret;
1739
}
1740
1741
/*
1742
* Function irlap_state_xmit_s (event, skb, info)
1743
*
1744
* XMIT_S, The secondary station has been given the right to transmit,
1745
* and we therefore do not expect to receive any transmissions from other
1746
* stations.
1747
*/
1748
static int irlap_state_xmit_s(struct irlap_cb *self, IRLAP_EVENT event,
1749
struct sk_buff *skb, struct irlap_info *info)
1750
{
1751
int ret = 0;
1752
1753
IRDA_DEBUG(4, "%s(), event=%s\n", __func__, irlap_event[event]);
1754
1755
IRDA_ASSERT(self != NULL, return -ENODEV;);
1756
IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
1757
1758
switch (event) {
1759
case SEND_I_CMD:
1760
/*
1761
* Send frame only if send window > 0
1762
*/
1763
if ((self->window > 0) && (!self->remote_busy)) {
1764
int nextfit;
1765
#ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1766
struct sk_buff *skb_next;
1767
1768
/*
1769
* Same deal as in irlap_state_xmit_p(), so see
1770
* the comments at that point.
1771
* We are the secondary, so there are only subtle
1772
* differences. - Jean II
1773
*/
1774
1775
/* Check if a subsequent skb exist and would fit in
1776
* the current window (with respect to turnaround
1777
* time). - Jean II */
1778
skb_next = skb_peek(&self->txq);
1779
nextfit = ((skb_next != NULL) &&
1780
((skb_next->len + skb->len) <=
1781
self->bytes_left));
1782
1783
/*
1784
* Test if we have transmitted more bytes over the
1785
* link than its possible to do with the current
1786
* speed and turn-around-time.
1787
*/
1788
if((!nextfit) && (skb->len > self->bytes_left)) {
1789
IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1790
" more bytes!\n", __func__);
1791
/* Requeue the skb */
1792
skb_queue_head(&self->txq, skb_get(skb));
1793
1794
/*
1795
* Switch to NRM_S, this is only possible
1796
* when we are in secondary mode, since we
1797
* must be sure that we don't miss any RR
1798
* frames
1799
*/
1800
self->window = self->window_size;
1801
self->bytes_left = self->line_capacity;
1802
irlap_start_wd_timer(self, self->wd_timeout);
1803
1804
irlap_next_state(self, LAP_NRM_S);
1805
/* Slight difference with primary :
1806
* here we would wait for the other side to
1807
* expire the turnaround. - Jean II */
1808
1809
return -EPROTO; /* Try again later */
1810
}
1811
/* Subtract space used by this skb */
1812
self->bytes_left -= skb->len;
1813
#else /* CONFIG_IRDA_DYNAMIC_WINDOW */
1814
/* Window has been adjusted for the max packet
1815
* size, so much simpler... - Jean II */
1816
nextfit = !skb_queue_empty(&self->txq);
1817
#endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1818
/*
1819
* Send data with final bit cleared only if window > 1
1820
* and there is more frames to be sent
1821
*/
1822
if ((self->window > 1) && (nextfit)) {
1823
irlap_send_data_secondary(self, skb);
1824
irlap_next_state(self, LAP_XMIT_S);
1825
} else {
1826
irlap_send_data_secondary_final(self, skb);
1827
irlap_next_state(self, LAP_NRM_S);
1828
1829
/*
1830
* Make sure state machine does not try to send
1831
* any more frames
1832
*/
1833
ret = -EPROTO;
1834
}
1835
} else {
1836
IRDA_DEBUG(2, "%s(), Unable to send!\n", __func__);
1837
skb_queue_head(&self->txq, skb_get(skb));
1838
ret = -EPROTO;
1839
}
1840
break;
1841
case DISCONNECT_REQUEST:
1842
irlap_send_rd_frame(self);
1843
irlap_flush_all_queues(self);
1844
irlap_start_wd_timer(self, self->wd_timeout);
1845
irlap_next_state(self, LAP_SCLOSE);
1846
break;
1847
case DATA_REQUEST:
1848
/* Nothing to do, irlap_do_event() will send the packet
1849
* when we return... - Jean II */
1850
break;
1851
default:
1852
IRDA_DEBUG(2, "%s(), Unknown event %s\n", __func__,
1853
irlap_event[event]);
1854
1855
ret = -EINVAL;
1856
break;
1857
}
1858
return ret;
1859
}
1860
1861
/*
1862
* Function irlap_state_nrm_s (event, skb, info)
1863
*
1864
* NRM_S (Normal Response Mode as Secondary) state, in this state we are
1865
* expecting to receive frames from the primary station
1866
*
1867
*/
1868
static int irlap_state_nrm_s(struct irlap_cb *self, IRLAP_EVENT event,
1869
struct sk_buff *skb, struct irlap_info *info)
1870
{
1871
int ns_status;
1872
int nr_status;
1873
int ret = 0;
1874
1875
IRDA_DEBUG(4, "%s(), event=%s\n", __func__, irlap_event[ event]);
1876
1877
IRDA_ASSERT(self != NULL, return -1;);
1878
IRDA_ASSERT(self->magic == LAP_MAGIC, return -1;);
1879
1880
switch (event) {
1881
case RECV_I_CMD: /* Optimize for the common case */
1882
/* FIXME: must check for remote_busy below */
1883
IRDA_DEBUG(4, "%s(), event=%s nr=%d, vs=%d, ns=%d, "
1884
"vr=%d, pf=%d\n", __func__,
1885
irlap_event[event], info->nr,
1886
self->vs, info->ns, self->vr, info->pf);
1887
1888
self->retry_count = 0;
1889
1890
ns_status = irlap_validate_ns_received(self, info->ns);
1891
nr_status = irlap_validate_nr_received(self, info->nr);
1892
/*
1893
* Check for expected I(nformation) frame
1894
*/
1895
if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1896
1897
/* Update Vr (next frame for us to receive) */
1898
self->vr = (self->vr + 1) % 8;
1899
1900
/* Update Nr received */
1901
irlap_update_nr_received(self, info->nr);
1902
1903
/*
1904
* poll bit cleared?
1905
*/
1906
if (!info->pf) {
1907
1908
self->ack_required = TRUE;
1909
1910
/*
1911
* Starting WD-timer here is optional, but
1912
* not recommended. Note 6 IrLAP p. 83
1913
*/
1914
#if 0
1915
irda_start_timer(WD_TIMER, self->wd_timeout);
1916
#endif
1917
/* Keep state, do not move this line */
1918
irlap_next_state(self, LAP_NRM_S);
1919
1920
irlap_data_indication(self, skb, FALSE);
1921
break;
1922
} else {
1923
/*
1924
* We should wait before sending RR, and
1925
* also before changing to XMIT_S
1926
* state. (note 1, IrLAP p. 82)
1927
*/
1928
irlap_wait_min_turn_around(self, &self->qos_tx);
1929
1930
/*
1931
* Give higher layers a chance to
1932
* immediately reply with some data before
1933
* we decide if we should send a RR frame
1934
* or not
1935
*/
1936
irlap_data_indication(self, skb, FALSE);
1937
1938
/* Any pending data requests? */
1939
if (!skb_queue_empty(&self->txq) &&
1940
(self->window > 0))
1941
{
1942
self->ack_required = TRUE;
1943
1944
del_timer(&self->wd_timer);
1945
1946
irlap_next_state(self, LAP_XMIT_S);
1947
} else {
1948
irlap_send_rr_frame(self, RSP_FRAME);
1949
irlap_start_wd_timer(self,
1950
self->wd_timeout);
1951
1952
/* Keep the state */
1953
irlap_next_state(self, LAP_NRM_S);
1954
}
1955
break;
1956
}
1957
}
1958
/*
1959
* Check for Unexpected next to send (Ns)
1960
*/
1961
if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1962
{
1963
/* Unexpected next to send, with final bit cleared */
1964
if (!info->pf) {
1965
irlap_update_nr_received(self, info->nr);
1966
1967
irlap_start_wd_timer(self, self->wd_timeout);
1968
} else {
1969
/* Update Nr received */
1970
irlap_update_nr_received(self, info->nr);
1971
1972
irlap_wait_min_turn_around(self, &self->qos_tx);
1973
irlap_send_rr_frame(self, RSP_FRAME);
1974
1975
irlap_start_wd_timer(self, self->wd_timeout);
1976
}
1977
break;
1978
}
1979
1980
/*
1981
* Unexpected Next to Receive(NR) ?
1982
*/
1983
if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1984
{
1985
if (info->pf) {
1986
IRDA_DEBUG(4, "RECV_I_RSP: frame(s) lost\n");
1987
1988
self->vr = (self->vr + 1) % 8;
1989
1990
/* Update Nr received */
1991
irlap_update_nr_received(self, info->nr);
1992
1993
/* Resend rejected frames */
1994
irlap_resend_rejected_frames(self, RSP_FRAME);
1995
1996
/* Keep state, do not move this line */
1997
irlap_next_state(self, LAP_NRM_S);
1998
1999
irlap_data_indication(self, skb, FALSE);
2000
irlap_start_wd_timer(self, self->wd_timeout);
2001
break;
2002
}
2003
/*
2004
* This is not documented in IrLAP!! Unexpected NR
2005
* with poll bit cleared
2006
*/
2007
if (!info->pf) {
2008
self->vr = (self->vr + 1) % 8;
2009
2010
/* Update Nr received */
2011
irlap_update_nr_received(self, info->nr);
2012
2013
/* Keep state, do not move this line */
2014
irlap_next_state(self, LAP_NRM_S);
2015
2016
irlap_data_indication(self, skb, FALSE);
2017
irlap_start_wd_timer(self, self->wd_timeout);
2018
}
2019
break;
2020
}
2021
2022
if (ret == NR_INVALID) {
2023
IRDA_DEBUG(0, "NRM_S, NR_INVALID not implemented!\n");
2024
}
2025
if (ret == NS_INVALID) {
2026
IRDA_DEBUG(0, "NRM_S, NS_INVALID not implemented!\n");
2027
}
2028
break;
2029
case RECV_UI_FRAME:
2030
/*
2031
* poll bit cleared?
2032
*/
2033
if (!info->pf) {
2034
irlap_data_indication(self, skb, TRUE);
2035
irlap_next_state(self, LAP_NRM_S); /* Keep state */
2036
} else {
2037
/*
2038
* Any pending data requests?
2039
*/
2040
if (!skb_queue_empty(&self->txq) &&
2041
(self->window > 0) && !self->remote_busy)
2042
{
2043
irlap_data_indication(self, skb, TRUE);
2044
2045
del_timer(&self->wd_timer);
2046
2047
irlap_next_state(self, LAP_XMIT_S);
2048
} else {
2049
irlap_data_indication(self, skb, TRUE);
2050
2051
irlap_wait_min_turn_around(self, &self->qos_tx);
2052
2053
irlap_send_rr_frame(self, RSP_FRAME);
2054
self->ack_required = FALSE;
2055
2056
irlap_start_wd_timer(self, self->wd_timeout);
2057
2058
/* Keep the state */
2059
irlap_next_state(self, LAP_NRM_S);
2060
}
2061
}
2062
break;
2063
case RECV_RR_CMD:
2064
self->retry_count = 0;
2065
2066
/*
2067
* Nr as expected?
2068
*/
2069
nr_status = irlap_validate_nr_received(self, info->nr);
2070
if (nr_status == NR_EXPECTED) {
2071
if (!skb_queue_empty(&self->txq) &&
2072
(self->window > 0)) {
2073
self->remote_busy = FALSE;
2074
2075
/* Update Nr received */
2076
irlap_update_nr_received(self, info->nr);
2077
del_timer(&self->wd_timer);
2078
2079
irlap_wait_min_turn_around(self, &self->qos_tx);
2080
irlap_next_state(self, LAP_XMIT_S);
2081
} else {
2082
self->remote_busy = FALSE;
2083
/* Update Nr received */
2084
irlap_update_nr_received(self, info->nr);
2085
irlap_wait_min_turn_around(self, &self->qos_tx);
2086
irlap_start_wd_timer(self, self->wd_timeout);
2087
2088
/* Note : if the link is idle (this case),
2089
* we never go in XMIT_S, so we never get a
2090
* chance to process any DISCONNECT_REQUEST.
2091
* Do it now ! - Jean II */
2092
if (self->disconnect_pending) {
2093
/* Disconnect */
2094
irlap_send_rd_frame(self);
2095
irlap_flush_all_queues(self);
2096
2097
irlap_next_state(self, LAP_SCLOSE);
2098
} else {
2099
/* Just send back pf bit */
2100
irlap_send_rr_frame(self, RSP_FRAME);
2101
2102
irlap_next_state(self, LAP_NRM_S);
2103
}
2104
}
2105
} else if (nr_status == NR_UNEXPECTED) {
2106
self->remote_busy = FALSE;
2107
irlap_update_nr_received(self, info->nr);
2108
irlap_resend_rejected_frames(self, RSP_FRAME);
2109
2110
irlap_start_wd_timer(self, self->wd_timeout);
2111
2112
/* Keep state */
2113
irlap_next_state(self, LAP_NRM_S);
2114
} else {
2115
IRDA_DEBUG(1, "%s(), invalid nr not implemented!\n",
2116
__func__);
2117
}
2118
break;
2119
case RECV_SNRM_CMD:
2120
/* SNRM frame is not allowed to contain an I-field */
2121
if (!info) {
2122
del_timer(&self->wd_timer);
2123
IRDA_DEBUG(1, "%s(), received SNRM cmd\n", __func__);
2124
irlap_next_state(self, LAP_RESET_CHECK);
2125
2126
irlap_reset_indication(self);
2127
} else {
2128
IRDA_DEBUG(0,
2129
"%s(), SNRM frame contained an I-field!\n",
2130
__func__);
2131
2132
}
2133
break;
2134
case RECV_REJ_CMD:
2135
irlap_update_nr_received(self, info->nr);
2136
if (self->remote_busy) {
2137
irlap_wait_min_turn_around(self, &self->qos_tx);
2138
irlap_send_rr_frame(self, RSP_FRAME);
2139
} else
2140
irlap_resend_rejected_frames(self, RSP_FRAME);
2141
irlap_start_wd_timer(self, self->wd_timeout);
2142
break;
2143
case RECV_SREJ_CMD:
2144
irlap_update_nr_received(self, info->nr);
2145
if (self->remote_busy) {
2146
irlap_wait_min_turn_around(self, &self->qos_tx);
2147
irlap_send_rr_frame(self, RSP_FRAME);
2148
} else
2149
irlap_resend_rejected_frame(self, RSP_FRAME);
2150
irlap_start_wd_timer(self, self->wd_timeout);
2151
break;
2152
case WD_TIMER_EXPIRED:
2153
/*
2154
* Wait until retry_count * n matches negotiated threshold/
2155
* disconnect time (note 2 in IrLAP p. 82)
2156
*
2157
* Similar to irlap_state_nrm_p() -> FINAL_TIMER_EXPIRED
2158
* Note : self->wd_timeout = (self->final_timeout * 2),
2159
* which explain why we use (self->N2 / 2) here !!!
2160
* Jean II
2161
*/
2162
IRDA_DEBUG(1, "%s(), retry_count = %d\n", __func__,
2163
self->retry_count);
2164
2165
if (self->retry_count < (self->N2 / 2)) {
2166
/* No retry, just wait for primary */
2167
irlap_start_wd_timer(self, self->wd_timeout);
2168
self->retry_count++;
2169
2170
if((self->retry_count % (self->N1 / 2)) == 0)
2171
irlap_status_indication(self,
2172
STATUS_NO_ACTIVITY);
2173
} else {
2174
irlap_apply_default_connection_parameters(self);
2175
2176
/* Always switch state before calling upper layers */
2177
irlap_next_state(self, LAP_NDM);
2178
irlap_disconnect_indication(self, LAP_NO_RESPONSE);
2179
}
2180
break;
2181
case RECV_DISC_CMD:
2182
/* Always switch state before calling upper layers */
2183
irlap_next_state(self, LAP_NDM);
2184
2185
/* Send disconnect response */
2186
irlap_wait_min_turn_around(self, &self->qos_tx);
2187
irlap_send_ua_response_frame(self, NULL);
2188
2189
del_timer(&self->wd_timer);
2190
irlap_flush_all_queues(self);
2191
/* Set default link parameters */
2192
irlap_apply_default_connection_parameters(self);
2193
2194
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2195
break;
2196
case RECV_DISCOVERY_XID_CMD:
2197
irlap_wait_min_turn_around(self, &self->qos_tx);
2198
irlap_send_rr_frame(self, RSP_FRAME);
2199
self->ack_required = TRUE;
2200
irlap_start_wd_timer(self, self->wd_timeout);
2201
irlap_next_state(self, LAP_NRM_S);
2202
2203
break;
2204
case RECV_TEST_CMD:
2205
/* Remove test frame header (only LAP header in NRM) */
2206
skb_pull(skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
2207
2208
irlap_wait_min_turn_around(self, &self->qos_tx);
2209
irlap_start_wd_timer(self, self->wd_timeout);
2210
2211
/* Send response (info will be copied) */
2212
irlap_send_test_frame(self, self->caddr, info->daddr, skb);
2213
break;
2214
default:
2215
IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __func__,
2216
event, irlap_event[event]);
2217
2218
ret = -EINVAL;
2219
break;
2220
}
2221
return ret;
2222
}
2223
2224
/*
2225
* Function irlap_state_sclose (self, event, skb, info)
2226
*/
2227
static int irlap_state_sclose(struct irlap_cb *self, IRLAP_EVENT event,
2228
struct sk_buff *skb, struct irlap_info *info)
2229
{
2230
IRDA_DEBUG(1, "%s()\n", __func__);
2231
2232
IRDA_ASSERT(self != NULL, return -ENODEV;);
2233
IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2234
2235
switch (event) {
2236
case RECV_DISC_CMD:
2237
/* Always switch state before calling upper layers */
2238
irlap_next_state(self, LAP_NDM);
2239
2240
/* Send disconnect response */
2241
irlap_wait_min_turn_around(self, &self->qos_tx);
2242
irlap_send_ua_response_frame(self, NULL);
2243
2244
del_timer(&self->wd_timer);
2245
/* Set default link parameters */
2246
irlap_apply_default_connection_parameters(self);
2247
2248
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2249
break;
2250
case RECV_DM_RSP:
2251
/* IrLAP-1.1 p.82: in SCLOSE, S and I type RSP frames
2252
* shall take us down into default NDM state, like DM_RSP
2253
*/
2254
case RECV_RR_RSP:
2255
case RECV_RNR_RSP:
2256
case RECV_REJ_RSP:
2257
case RECV_SREJ_RSP:
2258
case RECV_I_RSP:
2259
/* Always switch state before calling upper layers */
2260
irlap_next_state(self, LAP_NDM);
2261
2262
del_timer(&self->wd_timer);
2263
irlap_apply_default_connection_parameters(self);
2264
2265
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2266
break;
2267
case WD_TIMER_EXPIRED:
2268
/* Always switch state before calling upper layers */
2269
irlap_next_state(self, LAP_NDM);
2270
2271
irlap_apply_default_connection_parameters(self);
2272
2273
irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2274
break;
2275
default:
2276
/* IrLAP-1.1 p.82: in SCLOSE, basically any received frame
2277
* with pf=1 shall restart the wd-timer and resend the rd:rsp
2278
*/
2279
if (info != NULL && info->pf) {
2280
del_timer(&self->wd_timer);
2281
irlap_wait_min_turn_around(self, &self->qos_tx);
2282
irlap_send_rd_frame(self);
2283
irlap_start_wd_timer(self, self->wd_timeout);
2284
break; /* stay in SCLOSE */
2285
}
2286
2287
IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __func__,
2288
event, irlap_event[event]);
2289
2290
break;
2291
}
2292
2293
return -1;
2294
}
2295
2296
static int irlap_state_reset_check( struct irlap_cb *self, IRLAP_EVENT event,
2297
struct sk_buff *skb,
2298
struct irlap_info *info)
2299
{
2300
int ret = 0;
2301
2302
IRDA_DEBUG(1, "%s(), event=%s\n", __func__, irlap_event[event]);
2303
2304
IRDA_ASSERT(self != NULL, return -ENODEV;);
2305
IRDA_ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2306
2307
switch (event) {
2308
case RESET_RESPONSE:
2309
irlap_send_ua_response_frame(self, &self->qos_rx);
2310
irlap_initiate_connection_state(self);
2311
irlap_start_wd_timer(self, WD_TIMEOUT);
2312
irlap_flush_all_queues(self);
2313
2314
irlap_next_state(self, LAP_NRM_S);
2315
break;
2316
case DISCONNECT_REQUEST:
2317
irlap_wait_min_turn_around(self, &self->qos_tx);
2318
irlap_send_rd_frame(self);
2319
irlap_start_wd_timer(self, WD_TIMEOUT);
2320
irlap_next_state(self, LAP_SCLOSE);
2321
break;
2322
default:
2323
IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __func__,
2324
event, irlap_event[event]);
2325
2326
ret = -EINVAL;
2327
break;
2328
}
2329
return ret;
2330
}
2331
2332