net/irda/irlap_event.c

   1 /*********************************************************************
   2  *
   3  * Filename:      irlap_event.c
   4  * Version:       0.9
   5  * Description:   IrLAP state machine implementation
   6  * Status:        Experimental.
   7  * Author:        Dag Brattli <dag@brattli.net>
   8  * Created at:    Sat Aug 16 00:59:29 1997
   9  * Modified at:   Sat Dec 25 21:07:57 1999
  10  * Modified by:   Dag Brattli <dag@brattli.net>
  11  *
  12  *     Copyright (c) 1998-2000 Dag Brattli <dag@brattli.net>,
  13  *     Copyright (c) 1998      Thomas Davis <ratbert@radiks.net>
  14  *     All Rights Reserved.
  15  *     Copyright (c) 2000-2003 Jean Tourrilhes <jt@hpl.hp.com>
  16  *
  17  *     This program is free software; you can redistribute it and/or
  18  *     modify it under the terms of the GNU General Public License as
  19  *     published by the Free Software Foundation; either version 2 of
  20  *     the License, or (at your option) any later version.
  21  *
  22  *     Neither Dag Brattli nor University of 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/config.h>
  29 #include <linux/string.h>
  30 #include <linux/kernel.h>
  31 #include <linux/delay.h>
  32 #include <linux/skbuff.h>
  33
  34 #include <net/irda/irda.h>
  35 #include <net/irda/irlap_event.h>
  36
  37 #include <net/irda/timer.h>
  38 #include <net/irda/irlap.h>
  39 #include <net/irda/irlap_frame.h>
  40 #include <net/irda/qos.h>
  41 #include <net/irda/parameters.h>
  42 #include <net/irda/irlmp.h>             /* irlmp_flow_indication(), ... */
  43
  44 #include <net/irda/irda_device.h>
  45
  46 #ifdef CONFIG_IRDA_FAST_RR
  47 int sysctl_fast_poll_increase = 50;
  48 #endif
  49
  50 static int irlap_state_ndm    (struct irlap_cb *self, IRLAP_EVENT event,
  51                                struct sk_buff *skb, struct irlap_info *info);
  52 static int irlap_state_query  (struct irlap_cb *self, IRLAP_EVENT event,
  53                                struct sk_buff *skb, struct irlap_info *info);
  54 static int irlap_state_reply  (struct irlap_cb *self, IRLAP_EVENT event,
  55                                struct sk_buff *skb, struct irlap_info *info);
  56 static int irlap_state_conn   (struct irlap_cb *self, IRLAP_EVENT event,
  57                                struct sk_buff *skb, struct irlap_info *info);
  58 static int irlap_state_setup  (struct irlap_cb *self, IRLAP_EVENT event,
  59                                struct sk_buff *skb, struct irlap_info *info);
  60 static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
  61                                struct sk_buff *skb, struct irlap_info *info);
  62 static int irlap_state_xmit_p (struct irlap_cb *self, IRLAP_EVENT event,
  63                                struct sk_buff *skb, struct irlap_info *info);
  64 static int irlap_state_pclose (struct irlap_cb *self, IRLAP_EVENT event,
  65                                struct sk_buff *skb, struct irlap_info *info);
  66 static int irlap_state_nrm_p  (struct irlap_cb *self, IRLAP_EVENT event,
  67                                struct sk_buff *skb, struct irlap_info *info);
  68 static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
  69                                   struct sk_buff *skb, struct irlap_info *info);
  70 static int irlap_state_reset  (struct irlap_cb *self, IRLAP_EVENT event,
  71                                struct sk_buff *skb, struct irlap_info *info);
  72 static int irlap_state_nrm_s  (struct irlap_cb *self, IRLAP_EVENT event,
  73                                struct sk_buff *skb, struct irlap_info *info);
  74 static int irlap_state_xmit_s (struct irlap_cb *self, IRLAP_EVENT event,
  75                                struct sk_buff *skb, struct irlap_info *info);
  76 static int irlap_state_sclose (struct irlap_cb *self, IRLAP_EVENT event,
  77                                struct sk_buff *skb, struct irlap_info *info);
  78 static int irlap_state_reset_check(struct irlap_cb *, IRLAP_EVENT event,
  79                                    struct sk_buff *, struct irlap_info *);
  80
  81 #ifdef CONFIG_IRDA_DEBUG
  82 static const char *irlap_event[] = {
  83         "DISCOVERY_REQUEST",
  84         "CONNECT_REQUEST",
  85         "CONNECT_RESPONSE",
  86         "DISCONNECT_REQUEST",
  87         "DATA_REQUEST",
  88         "RESET_REQUEST",
  89         "RESET_RESPONSE",
  90         "SEND_I_CMD",
  91         "SEND_UI_FRAME",
  92         "RECV_DISCOVERY_XID_CMD",
  93         "RECV_DISCOVERY_XID_RSP",
  94         "RECV_SNRM_CMD",
  95         "RECV_TEST_CMD",
  96         "RECV_TEST_RSP",
  97         "RECV_UA_RSP",
  98         "RECV_DM_RSP",
  99         "RECV_RD_RSP",
 100         "RECV_I_CMD",
 101         "RECV_I_RSP",
 102         "RECV_UI_FRAME",
 103         "RECV_FRMR_RSP",
 104         "RECV_RR_CMD",
 105         "RECV_RR_RSP",
 106         "RECV_RNR_CMD",
 107         "RECV_RNR_RSP",
 108         "RECV_REJ_CMD",
 109         "RECV_REJ_RSP",
 110         "RECV_SREJ_CMD",
 111         "RECV_SREJ_RSP",
 112         "RECV_DISC_CMD",
 113         "SLOT_TIMER_EXPIRED",
 114         "QUERY_TIMER_EXPIRED",
 115         "FINAL_TIMER_EXPIRED",
 116         "POLL_TIMER_EXPIRED",
 117         "DISCOVERY_TIMER_EXPIRED",
 118         "WD_TIMER_EXPIRED",
 119         "BACKOFF_TIMER_EXPIRED",
 120         "MEDIA_BUSY_TIMER_EXPIRED",
 121 };
 122 #endif  /* CONFIG_IRDA_DEBUG */
 123
 124 const char *irlap_state[] = {
 125         "LAP_NDM",
 126         "LAP_QUERY",
 127         "LAP_REPLY",
 128         "LAP_CONN",
 129         "LAP_SETUP",
 130         "LAP_OFFLINE",
 131         "LAP_XMIT_P",
 132         "LAP_PCLOSE",
 133         "LAP_NRM_P",
 134         "LAP_RESET_WAIT",
 135         "LAP_RESET",
 136         "LAP_NRM_S",
 137         "LAP_XMIT_S",
 138         "LAP_SCLOSE",
 139         "LAP_RESET_CHECK",
 140 };
 141
 142 static int (*state[])(struct irlap_cb *self, IRLAP_EVENT event,
 143                       struct sk_buff *skb, struct irlap_info *info) =
 144 {
 145         irlap_state_ndm,
 146         irlap_state_query,
 147         irlap_state_reply,
 148         irlap_state_conn,
 149         irlap_state_setup,
 150         irlap_state_offline,
 151         irlap_state_xmit_p,
 152         irlap_state_pclose,
 153         irlap_state_nrm_p,
 154         irlap_state_reset_wait,
 155         irlap_state_reset,
 156         irlap_state_nrm_s,
 157         irlap_state_xmit_s,
 158         irlap_state_sclose,
 159         irlap_state_reset_check,
 160 };
 161
 162 /*
 163  * Function irda_poll_timer_expired (data)
 164  *
 165  *    Poll timer has expired. Normally we must now send a RR frame to the
 166  *    remote device
 167  */
 168 static void irlap_poll_timer_expired(void *data)
 169 {
 170         struct irlap_cb *self = (struct irlap_cb *) data;
 171
 172         ASSERT(self != NULL, return;);
 173         ASSERT(self->magic == LAP_MAGIC, return;);
 174
 175         irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
 176 }
 177
 178 /*
 179  * Calculate and set time before we will have to send back the pf bit
 180  * to the peer. Use in primary.
 181  * Make sure that state is XMIT_P/XMIT_S when calling this function
 182  * (and that nobody messed up with the state). - Jean II
 183  */
 184 void irlap_start_poll_timer(struct irlap_cb *self, int timeout)
 185 {
 186         ASSERT(self != NULL, return;);
 187         ASSERT(self->magic == LAP_MAGIC, return;);
 188
 189 #ifdef CONFIG_IRDA_FAST_RR
 190         /*
 191          * Send out the RR frames faster if our own transmit queue is empty, or
 192          * if the peer is busy. The effect is a much faster conversation
 193          */
 194         if ((skb_queue_len(&self->txq) == 0) || (self->remote_busy)) {
 195                 if (self->fast_RR == TRUE) {
 196                         /*
 197                          *  Assert that the fast poll timer has not reached the
 198                          *  normal poll timer yet
 199                          */
 200                         if (self->fast_RR_timeout < timeout) {
 201                                 /*
 202                                  *  FIXME: this should be a more configurable
 203                                  *         function
 204                                  */
 205                                 self->fast_RR_timeout +=
 206                                         (sysctl_fast_poll_increase * HZ/1000);
 207
 208                                 /* Use this fast(er) timeout instead */
 209                                 timeout = self->fast_RR_timeout;
 210                         }
 211                 } else {
 212                         self->fast_RR = TRUE;
 213
 214                         /* Start with just 0 ms */
 215                         self->fast_RR_timeout = 0;
 216                         timeout = 0;
 217                 }
 218         } else
 219                 self->fast_RR = FALSE;
 220
 221         IRDA_DEBUG(3, "%s(), timeout=%d (%ld)\n", __FUNCTION__, timeout, jiffies);
 222 #endif /* CONFIG_IRDA_FAST_RR */
 223
 224         if (timeout == 0)
 225                 irlap_do_event(self, POLL_TIMER_EXPIRED, NULL, NULL);
 226         else
 227                 irda_start_timer(&self->poll_timer, timeout, self,
 228                                  irlap_poll_timer_expired);
 229 }
 230
 231 /*
 232  * Function irlap_do_event (event, skb, info)
 233  *
 234  *    Rushes through the state machine without any delay. If state == XMIT
 235  *    then send queued data frames.
 236  */
 237 void irlap_do_event(struct irlap_cb *self, IRLAP_EVENT event,
 238                     struct sk_buff *skb, struct irlap_info *info)
 239 {
 240         int ret;
 241
 242         if (!self || self->magic != LAP_MAGIC)
 243                 return;
 244
 245         IRDA_DEBUG(3, "%s(), event = %s, state = %s\n", __FUNCTION__,
 246                    irlap_event[event], irlap_state[self->state]);
 247
 248         ret = (*state[self->state])(self, event, skb, info);
 249
 250         /*
 251          *  Check if there are any pending events that needs to be executed
 252          */
 253         switch (self->state) {
 254         case LAP_XMIT_P: /* FALLTHROUGH */
 255         case LAP_XMIT_S:
 256                 /*
 257                  * We just received the pf bit and are at the beginning
 258                  * of a new LAP transmit window.
 259                  * Check if there are any queued data frames, and do not
 260                  * try to disconnect link if we send any data frames, since
 261                  * that will change the state away form XMIT
 262                  */
 263                 IRDA_DEBUG(2, "%s() : queue len = %d\n", __FUNCTION__,
 264                            skb_queue_len(&self->txq));
 265
 266                 if (skb_queue_len(&self->txq)) {
 267                         /* Prevent race conditions with irlap_data_request() */
 268                         self->local_busy = TRUE;
 269
 270                         /* Theory of operation.
 271                          * We send frames up to when we fill the window or
 272                          * reach line capacity. Those frames will queue up
 273                          * in the device queue, and the driver will slowly
 274                          * send them.
 275                          * After each frame that we send, we poll the higher
 276                          * layer for more data. It's the right time to do
 277                          * that because the link layer need to perform the mtt
 278                          * and then send the first frame, so we can afford
 279                          * to send a bit of time in kernel space.
 280                          * The explicit flow indication allow to minimise
 281                          * buffers (== lower latency), to avoid higher layer
 282                          * polling via timers (== less context switches) and
 283                          * to implement a crude scheduler - Jean II */
 284
 285                         /* Try to send away all queued data frames */
 286                         while ((skb = skb_dequeue(&self->txq)) != NULL) {
 287                                 /* Send one frame */
 288                                 ret = (*state[self->state])(self, SEND_I_CMD,
 289                                                             skb, NULL);
 290                                 /* Drop reference count.
 291                                  * It will be increase as needed in
 292                                  * irlap_send_data_xxx() */
 293                                 kfree_skb(skb);
 294
 295                                 /* Poll the higher layers for one more frame */
 296                                 irlmp_flow_indication(self->notify.instance,
 297                                                       FLOW_START);
 298
 299                                 if (ret == -EPROTO)
 300                                         break; /* Try again later! */
 301                         }
 302                         /* Finished transmitting */
 303                         self->local_busy = FALSE;
 304                 } else if (self->disconnect_pending) {
 305                         self->disconnect_pending = FALSE;
 306
 307                         ret = (*state[self->state])(self, DISCONNECT_REQUEST,
 308                                                     NULL, NULL);
 309                 }
 310                 break;
 311 /*      case LAP_NDM: */
 312 /*      case LAP_CONN: */
 313 /*      case LAP_RESET_WAIT: */
 314 /*      case LAP_RESET_CHECK: */
 315         default:
 316                 break;
 317         }
 318 }
 319
 320 /*
 321  * Function irlap_next_state (self, state)
 322  *
 323  *    Switches state and provides debug information
 324  *
 325  */
 326 static inline void irlap_next_state(struct irlap_cb *self, IRLAP_STATE state)
 327 {
 328         /*
 329         if (!self || self->magic != LAP_MAGIC)
 330                 return;
 331
 332         IRDA_DEBUG(4, "next LAP state = %s\n", irlap_state[state]);
 333         */
 334         self->state = state;
 335 }
 336
 337 /*
 338  * Function irlap_state_ndm (event, skb, frame)
 339  *
 340  *    NDM (Normal Disconnected Mode) state
 341  *
 342  */
 343 static int irlap_state_ndm(struct irlap_cb *self, IRLAP_EVENT event,
 344                            struct sk_buff *skb, struct irlap_info *info)
 345 {
 346         discovery_t *discovery_rsp;
 347         int ret = 0;
 348
 349         ASSERT(self != NULL, return -1;);
 350         ASSERT(self->magic == LAP_MAGIC, return -1;);
 351
 352         switch (event) {
 353         case CONNECT_REQUEST:
 354                 ASSERT(self->netdev != NULL, return -1;);
 355
 356                 if (self->media_busy) {
 357                         /* Note : this will never happen, because we test
 358                          * media busy in irlap_connect_request() and
 359                          * postpone the event... - Jean II */
 360                         IRDA_DEBUG(0, "%s(), CONNECT_REQUEST: media busy!\n",
 361                                    __FUNCTION__);
 362
 363                         /* Always switch state before calling upper layers */
 364                         irlap_next_state(self, LAP_NDM);
 365
 366                         irlap_disconnect_indication(self, LAP_MEDIA_BUSY);
 367                 } else {
 368                         irlap_send_snrm_frame(self, &self->qos_rx);
 369
 370                         /* Start Final-bit timer */
 371                         irlap_start_final_timer(self, self->final_timeout);
 372
 373                         self->retry_count = 0;
 374                         irlap_next_state(self, LAP_SETUP);
 375                 }
 376                 break;
 377         case RECV_SNRM_CMD:
 378                 /* Check if the frame contains and I field */
 379                 if (info) {
 380                         self->daddr = info->daddr;
 381                         self->caddr = info->caddr;
 382
 383                         irlap_next_state(self, LAP_CONN);
 384
 385                         irlap_connect_indication(self, skb);
 386                 } else {
 387                         IRDA_DEBUG(0, "%s(), SNRM frame does not "
 388                                    "contain an I field!\n", __FUNCTION__);
 389                 }
 390                 break;
 391         case DISCOVERY_REQUEST:
 392                 ASSERT(info != NULL, return -1;);
 393
 394                 if (self->media_busy) {
 395                         IRDA_DEBUG(0, "%s(), media busy!\n", __FUNCTION__);
 396                         /* irlap->log.condition = MEDIA_BUSY; */
 397
 398                         /* This will make IrLMP try again */
 399                         irlap_discovery_confirm(self, NULL);
 400                         /* Note : the discovery log is not cleaned up here,
 401                          * it will be done in irlap_discovery_request()
 402                          * Jean II */
 403                         return 0;
 404                 }
 405
 406                 self->S = info->S;
 407                 self->s = info->s;
 408                 irlap_send_discovery_xid_frame(self, info->S, info->s, TRUE,
 409                                                info->discovery);
 410                 self->frame_sent = FALSE;
 411                 self->s++;
 412
 413                 irlap_start_slot_timer(self, self->slot_timeout);
 414                 irlap_next_state(self, LAP_QUERY);
 415                 break;
 416         case RECV_DISCOVERY_XID_CMD:
 417                 ASSERT(info != NULL, return -1;);
 418
 419                 /* Assert that this is not the final slot */
 420                 if (info->s <= info->S) {
 421                         self->slot = irlap_generate_rand_time_slot(info->S,
 422                                                                    info->s);
 423                         if (self->slot == info->s) {
 424                                 discovery_rsp = irlmp_get_discovery_response();
 425                                 discovery_rsp->data.daddr = info->daddr;
 426
 427                                 irlap_send_discovery_xid_frame(self, info->S,
 428                                                                self->slot,
 429                                                                FALSE,
 430                                                                discovery_rsp);
 431                                 self->frame_sent = TRUE;
 432                         } else
 433                                 self->frame_sent = FALSE;
 434
 435                         /*
 436                          * Remember to multiply the query timeout value with
 437                          * the number of slots used
 438                          */
 439                         irlap_start_query_timer(self, QUERY_TIMEOUT*info->S);
 440                         irlap_next_state(self, LAP_REPLY);
 441                 } else {
 442                 /* This is the final slot. How is it possible ?
 443                  * This would happen is both discoveries are just slightly
 444                  * offset (if they are in sync, all packets are lost).
 445                  * Most often, all the discovery requests will be received
 446                  * in QUERY state (see my comment there), except for the
 447                  * last frame that will come here.
 448                  * The big trouble when it happen is that active discovery
 449                  * doesn't happen, because nobody answer the discoveries
 450                  * frame of the other guy, so the log shows up empty.
 451                  * What should we do ?
 452                  * Not much. It's too late to answer those discovery frames,
 453                  * so we just pass the info to IrLMP who will put it in the
 454                  * log (and post an event).
 455                  * Jean II
 456                  */
 457                         IRDA_DEBUG(1, "%s(), Receiving final discovery request, missed the discovery slots :-(\n", __FUNCTION__);
 458
 459                         /* Last discovery request -> in the log */
 460                         irlap_discovery_indication(self, info->discovery);
 461                 }
 462                 break;
 463         case MEDIA_BUSY_TIMER_EXPIRED:
 464                 /* A bunch of events may be postponed because the media is
 465                  * busy (usually immediately after we close a connection),
 466                  * or while we are doing discovery (state query/reply).
 467                  * In all those cases, the media busy flag will be cleared
 468                  * when it's OK for us to process those postponed events.
 469                  * This event is not mentioned in the state machines in the
 470                  * IrLAP spec. It's because they didn't consider Ultra and
 471                  * postponing connection request is optional.
 472                  * Jean II */
 473 #ifdef CONFIG_IRDA_ULTRA
 474                 /* Send any pending Ultra frames if any */
 475                 if (!skb_queue_empty(&self->txq_ultra)) {
 476                         /* We don't send the frame, just post an event.
 477                          * Also, previously this code was in timer.c...
 478                          * Jean II */
 479                         ret = (*state[self->state])(self, SEND_UI_FRAME,
 480                                                     NULL, NULL);
 481                 }
 482 #endif /* CONFIG_IRDA_ULTRA */
 483                 /* Check if we should try to connect.
 484                  * This code was previously in irlap_do_event() */
 485                 if (self->connect_pending) {
 486                         self->connect_pending = FALSE;
 487
 488                         /* This one *should* not pend in this state, except
 489                          * if a socket try to connect and immediately
 490                          * disconnect. - clear - Jean II */
 491                         if (self->disconnect_pending)
 492                                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
 493                         else
 494                                 ret = (*state[self->state])(self,
 495                                                             CONNECT_REQUEST,
 496                                                             NULL, NULL);
 497                         self->disconnect_pending = FALSE;
 498                 }
 499                 /* Note : one way to test if this code works well (including
 500                  * media busy and small busy) is to create a user space
 501                  * application generating an Ultra packet every 3.05 sec (or
 502                  * 2.95 sec) and to see how it interact with discovery.
 503                  * It's fairly easy to check that no packet is lost, that the
 504                  * packets are postponed during discovery and that after
 505                  * discovery indication you have a 100ms "gap".
 506                  * As connection request and Ultra are now processed the same
 507                  * way, this avoid the tedious job of trying IrLAP connection
 508                  * in all those cases...
 509                  * Jean II */
 510                 break;
 511 #ifdef CONFIG_IRDA_ULTRA
 512         case SEND_UI_FRAME:
 513         {
 514                 int i;
 515                 /* Only allowed to repeat an operation twice */
 516                 for (i=0; ((i<2) && (self->media_busy == FALSE)); i++) {
 517                         skb = skb_dequeue(&self->txq_ultra);
 518                         if (skb)
 519                                 irlap_send_ui_frame(self, skb, CBROADCAST,
 520                                                     CMD_FRAME);
 521                         else
 522                                 break;
 523                         /* irlap_send_ui_frame() won't increase skb reference
 524                          * count, so no dev_kfree_skb() - Jean II */
 525                 }
 526                 if (i == 2) {
 527                         /* Force us to listen 500 ms again */
 528                         irda_device_set_media_busy(self->netdev, TRUE);
 529                 }
 530                 break;
 531         }
 532         case RECV_UI_FRAME:
 533                 /* Only accept broadcast frames in NDM mode */
 534                 if (info->caddr != CBROADCAST) {
 535                         IRDA_DEBUG(0, "%s(), not a broadcast frame!\n",
 536                                    __FUNCTION__);
 537                 } else
 538                         irlap_unitdata_indication(self, skb);
 539                 break;
 540 #endif /* CONFIG_IRDA_ULTRA */
 541         case RECV_TEST_CMD:
 542                 /* Remove test frame header */
 543                 skb_pull(skb, sizeof(struct test_frame));
 544
 545                 /*
 546                  * Send response. This skb will not be sent out again, and
 547                  * will only be used to send out the same info as the cmd
 548                  */
 549                 irlap_send_test_frame(self, CBROADCAST, info->daddr, skb);
 550                 break;
 551         case RECV_TEST_RSP:
 552                 IRDA_DEBUG(0, "%s() not implemented!\n", __FUNCTION__);
 553                 break;
 554         default:
 555                 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
 556                            irlap_event[event]);
 557
 558                 ret = -1;
 559                 break;
 560         }
 561         return ret;
 562 }
 563
 564 /*
 565  * Function irlap_state_query (event, skb, info)
 566  *
 567  *    QUERY state
 568  *
 569  */
 570 static int irlap_state_query(struct irlap_cb *self, IRLAP_EVENT event,
 571                              struct sk_buff *skb, struct irlap_info *info)
 572 {
 573         int ret = 0;
 574
 575         ASSERT(self != NULL, return -1;);
 576         ASSERT(self->magic == LAP_MAGIC, return -1;);
 577
 578         switch (event) {
 579         case RECV_DISCOVERY_XID_RSP:
 580                 ASSERT(info != NULL, return -1;);
 581                 ASSERT(info->discovery != NULL, return -1;);
 582
 583                 IRDA_DEBUG(4, "%s(), daddr=%08x\n", __FUNCTION__,
 584                            info->discovery->data.daddr);
 585
 586                 if (!self->discovery_log) {
 587                         WARNING("%s: discovery log is gone! "
 588                                 "maybe the discovery timeout has been set to "
 589                                 "short?\n", __FUNCTION__);
 590                         break;
 591                 }
 592                 hashbin_insert(self->discovery_log,
 593                                (irda_queue_t *) info->discovery,
 594                                info->discovery->data.daddr, NULL);
 595
 596                 /* Keep state */
 597                 /* irlap_next_state(self, LAP_QUERY);  */
 598
 599                 break;
 600         case RECV_DISCOVERY_XID_CMD:
 601                 /* Yes, it is possible to receive those frames in this mode.
 602                  * Note that most often the last discovery request won't
 603                  * occur here but in NDM state (see my comment there).
 604                  * What should we do ?
 605                  * Not much. We are currently performing our own discovery,
 606                  * therefore we can't answer those frames. We don't want
 607                  * to change state either. We just pass the info to
 608                  * IrLMP who will put it in the log (and post an event).
 609                  * Jean II
 610                  */
 611
 612                 ASSERT(info != NULL, return -1;);
 613
 614                 IRDA_DEBUG(1, "%s(), Receiving discovery request (s = %d) while performing discovery :-(\n", __FUNCTION__, info->s);
 615
 616                 /* Last discovery request ? */
 617                 if (info->s == 0xff)
 618                         irlap_discovery_indication(self, info->discovery);
 619                 break;
 620         case SLOT_TIMER_EXPIRED:
 621                 /*
 622                  * Wait a little longer if we detect an incoming frame. This
 623                  * is not mentioned in the spec, but is a good thing to do,
 624                  * since we want to work even with devices that violate the
 625                  * timing requirements.
 626                  */
 627                 if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
 628                         IRDA_DEBUG(2, "%s(), device is slow to answer, "
 629                                    "waiting some more!\n", __FUNCTION__);
 630                         irlap_start_slot_timer(self, msecs_to_jiffies(10));
 631                         self->add_wait = TRUE;
 632                         return ret;
 633                 }
 634                 self->add_wait = FALSE;
 635
 636                 if (self->s < self->S) {
 637                         irlap_send_discovery_xid_frame(self, self->S,
 638                                                        self->s, TRUE,
 639                                                        self->discovery_cmd);
 640                         self->s++;
 641                         irlap_start_slot_timer(self, self->slot_timeout);
 642
 643                         /* Keep state */
 644                         irlap_next_state(self, LAP_QUERY);
 645                 } else {
 646                         /* This is the final slot! */
 647                         irlap_send_discovery_xid_frame(self, self->S, 0xff,
 648                                                        TRUE,
 649                                                        self->discovery_cmd);
 650
 651                         /* Always switch state before calling upper layers */
 652                         irlap_next_state(self, LAP_NDM);
 653
 654                         /*
 655                          *  We are now finished with the discovery procedure,
 656                          *  so now we must return the results
 657                          */
 658                         irlap_discovery_confirm(self, self->discovery_log);
 659
 660                         /* IrLMP should now have taken care of the log */
 661                         self->discovery_log = NULL;
 662                 }
 663                 break;
 664         default:
 665                 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
 666                            irlap_event[event]);
 667
 668                 ret = -1;
 669                 break;
 670         }
 671         return ret;
 672 }
 673
 674 /*
 675  * Function irlap_state_reply (self, event, skb, info)
 676  *
 677  *    REPLY, we have received a XID discovery frame from a device and we
 678  *    are waiting for the right time slot to send a response XID frame
 679  *
 680  */
 681 static int irlap_state_reply(struct irlap_cb *self, IRLAP_EVENT event,
 682                              struct sk_buff *skb, struct irlap_info *info)
 683 {
 684         discovery_t *discovery_rsp;
 685         int ret=0;
 686
 687         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
 688
 689         ASSERT(self != NULL, return -1;);
 690         ASSERT(self->magic == LAP_MAGIC, return -1;);
 691
 692         switch (event) {
 693         case QUERY_TIMER_EXPIRED:
 694                 IRDA_DEBUG(2, "%s(), QUERY_TIMER_EXPIRED <%ld>\n",
 695                            __FUNCTION__, jiffies);
 696                 irlap_next_state(self, LAP_NDM);
 697                 break;
 698         case RECV_DISCOVERY_XID_CMD:
 699                 ASSERT(info != NULL, return -1;);
 700                 /* Last frame? */
 701                 if (info->s == 0xff) {
 702                         del_timer(&self->query_timer);
 703
 704                         /* info->log.condition = REMOTE; */
 705
 706                         /* Always switch state before calling upper layers */
 707                         irlap_next_state(self, LAP_NDM);
 708
 709                         irlap_discovery_indication(self, info->discovery);
 710                 } else if ((info->s >= self->slot) && (!self->frame_sent)) {
 711                         discovery_rsp = irlmp_get_discovery_response();
 712                         discovery_rsp->data.daddr = info->daddr;
 713
 714                         irlap_send_discovery_xid_frame(self, info->S,
 715                                                        self->slot, FALSE,
 716                                                        discovery_rsp);
 717
 718                         self->frame_sent = TRUE;
 719                         irlap_next_state(self, LAP_REPLY);
 720                 }
 721                 break;
 722         default:
 723                 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
 724                            event, irlap_event[event]);
 725
 726                 ret = -1;
 727                 break;
 728         }
 729         return ret;
 730 }
 731
 732 /*
 733  * Function irlap_state_conn (event, skb, info)
 734  *
 735  *    CONN, we have received a SNRM command and is waiting for the upper
 736  *    layer to accept or refuse connection
 737  *
 738  */
 739 static int irlap_state_conn(struct irlap_cb *self, IRLAP_EVENT event,
 740                             struct sk_buff *skb, struct irlap_info *info)
 741 {
 742         int ret = 0;
 743
 744         IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[ event]);
 745
 746         ASSERT(self != NULL, return -1;);
 747         ASSERT(self->magic == LAP_MAGIC, return -1;);
 748
 749         switch (event) {
 750         case CONNECT_RESPONSE:
 751                 skb_pull(skb, sizeof(struct snrm_frame));
 752
 753                 ASSERT(self->netdev != NULL, return -1;);
 754
 755                 irlap_qos_negotiate(self, skb);
 756
 757                 irlap_initiate_connection_state(self);
 758
 759                 /*
 760                  * Applying the parameters now will make sure we change speed
 761                  * *after* we have sent the next frame
 762                  */
 763                 irlap_apply_connection_parameters(self, FALSE);
 764
 765                 /*
 766                  * Sending this frame will force a speed change after it has
 767                  * been sent (i.e. the frame will be sent at 9600).
 768                  */
 769                 irlap_send_ua_response_frame(self, &self->qos_rx);
 770
 771 #if 0
 772                 /*
 773                  * We are allowed to send two frames, but this may increase
 774                  * the connect latency, so lets not do it for now.
 775                  */
 776                 /* This is full of good intentions, but doesn't work in
 777                  * practice.
 778                  * After sending the first UA response, we switch the
 779                  * dongle to the negotiated speed, which is usually
 780                  * different than 9600 kb/s.
 781                  * From there, there is two solutions :
 782                  * 1) The other end has received the first UA response :
 783                  * it will set up the connection, move to state LAP_NRM_P,
 784                  * and will ignore and drop the second UA response.
 785                  * Actually, it's even worse : the other side will almost
 786                  * immediately send a RR that will likely collide with the
 787                  * UA response (depending on negotiated turnaround).
 788                  * 2) The other end has not received the first UA response,
 789                  * will stay at 9600 and will never see the second UA response.
 790                  * Jean II */
 791                 irlap_send_ua_response_frame(self, &self->qos_rx);
 792 #endif
 793
 794                 /*
 795                  *  The WD-timer could be set to the duration of the P-timer
 796                  *  for this case, but it is recommended to use twice the
 797                  *  value (note 3 IrLAP p. 60).
 798                  */
 799                 irlap_start_wd_timer(self, self->wd_timeout);
 800                 irlap_next_state(self, LAP_NRM_S);
 801
 802                 break;
 803         case RECV_DISCOVERY_XID_CMD:
 804                 IRDA_DEBUG(3, "%s(), event RECV_DISCOVER_XID_CMD!\n",
 805                            __FUNCTION__);
 806                 irlap_next_state(self, LAP_NDM);
 807
 808                 break;
 809         case DISCONNECT_REQUEST:
 810                 IRDA_DEBUG(0, "%s(), Disconnect request!\n", __FUNCTION__);
 811                 irlap_send_dm_frame(self);
 812                 irlap_next_state( self, LAP_NDM);
 813                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
 814                 break;
 815         default:
 816                 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
 817                            event, irlap_event[event]);
 818
 819                 ret = -1;
 820                 break;
 821         }
 822
 823         return ret;
 824 }
 825
 826 /*
 827  * Function irlap_state_setup (event, skb, frame)
 828  *
 829  *    SETUP state, The local layer has transmitted a SNRM command frame to
 830  *    a remote peer layer and is awaiting a reply .
 831  *
 832  */
 833 static int irlap_state_setup(struct irlap_cb *self, IRLAP_EVENT event,
 834                              struct sk_buff *skb, struct irlap_info *info)
 835 {
 836         int ret = 0;
 837
 838         IRDA_DEBUG(4, "%s()\n", __FUNCTION__);
 839
 840         ASSERT(self != NULL, return -1;);
 841         ASSERT(self->magic == LAP_MAGIC, return -1;);
 842
 843         switch (event) {
 844         case FINAL_TIMER_EXPIRED:
 845                 if (self->retry_count < self->N3) {
 846 /*
 847  *  Perform random backoff, Wait a random number of time units, minimum
 848  *  duration half the time taken to transmitt a SNRM frame, maximum duration
 849  *  1.5 times the time taken to transmit a SNRM frame. So this time should
 850  *  between 15 msecs and 45 msecs.
 851  */
 852                         irlap_start_backoff_timer(self, msecs_to_jiffies(20 +
 853                                                         (jiffies % 30)));
 854                 } else {
 855                         /* Always switch state before calling upper layers */
 856                         irlap_next_state(self, LAP_NDM);
 857
 858                         irlap_disconnect_indication(self, LAP_FOUND_NONE);
 859                 }
 860                 break;
 861         case BACKOFF_TIMER_EXPIRED:
 862                 irlap_send_snrm_frame(self, &self->qos_rx);
 863                 irlap_start_final_timer(self, self->final_timeout);
 864                 self->retry_count++;
 865                 break;
 866         case RECV_SNRM_CMD:
 867                 IRDA_DEBUG(4, "%s(), SNRM battle!\n", __FUNCTION__);
 868
 869                 ASSERT(skb != NULL, return 0;);
 870                 ASSERT(info != NULL, return 0;);
 871
 872                 /*
 873                  *  The device with the largest device address wins the battle
 874                  *  (both have sent a SNRM command!)
 875                  */
 876                 if (info &&(info->daddr > self->saddr)) {
 877                         del_timer(&self->final_timer);
 878                         irlap_initiate_connection_state(self);
 879
 880                         ASSERT(self->netdev != NULL, return -1;);
 881
 882                         skb_pull(skb, sizeof(struct snrm_frame));
 883
 884                         irlap_qos_negotiate(self, skb);
 885
 886                         /* Send UA frame and then change link settings */
 887                         irlap_apply_connection_parameters(self, FALSE);
 888                         irlap_send_ua_response_frame(self, &self->qos_rx);
 889
 890                         irlap_next_state(self, LAP_NRM_S);
 891                         irlap_connect_confirm(self, skb);
 892
 893                         /*
 894                          *  The WD-timer could be set to the duration of the
 895                          *  P-timer for this case, but it is recommended
 896                          *  to use twice the value (note 3 IrLAP p. 60).
 897                          */
 898                         irlap_start_wd_timer(self, self->wd_timeout);
 899                 } else {
 900                         /* We just ignore the other device! */
 901                         irlap_next_state(self, LAP_SETUP);
 902                 }
 903                 break;
 904         case RECV_UA_RSP:
 905                 /* Stop F-timer */
 906                 del_timer(&self->final_timer);
 907
 908                 /* Initiate connection state */
 909                 irlap_initiate_connection_state(self);
 910
 911                 /* Negotiate connection parameters */
 912                 ASSERT(skb->len > 10, return -1;);
 913
 914                 skb_pull(skb, sizeof(struct ua_frame));
 915
 916                 ASSERT(self->netdev != NULL, return -1;);
 917
 918                 irlap_qos_negotiate(self, skb);
 919
 920                 /* Set the new link setting *now* (before the rr frame) */
 921                 irlap_apply_connection_parameters(self, TRUE);
 922                 self->retry_count = 0;
 923
 924                 /* Wait for turnaround time to give a chance to the other
 925                  * device to be ready to receive us.
 926                  * Note : the time to switch speed is typically larger
 927                  * than the turnaround time, but as we don't have the other
 928                  * side speed switch time, that's our best guess...
 929                  * Jean II */
 930                 irlap_wait_min_turn_around(self, &self->qos_tx);
 931
 932                 /* This frame will actually be sent at the new speed */
 933                 irlap_send_rr_frame(self, CMD_FRAME);
 934
 935                 /* The timer is set to half the normal timer to quickly
 936                  * detect a failure to negociate the new connection
 937                  * parameters. IrLAP 6.11.3.2, note 3.
 938                  * Note that currently we don't process this failure
 939                  * properly, as we should do a quick disconnect.
 940                  * Jean II */
 941                 irlap_start_final_timer(self, self->final_timeout/2);
 942                 irlap_next_state(self, LAP_NRM_P);
 943
 944                 irlap_connect_confirm(self, skb);
 945                 break;
 946         case RECV_DM_RSP:     /* FALLTHROUGH */
 947         case RECV_DISC_CMD:
 948                 del_timer(&self->final_timer);
 949                 irlap_next_state(self, LAP_NDM);
 950
 951                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
 952                 break;
 953         default:
 954                 IRDA_DEBUG(1, "%s(), Unknown event %d, %s\n", __FUNCTION__,
 955                            event, irlap_event[event]);
 956
 957                 ret = -1;
 958                 break;
 959         }
 960         return ret;
 961 }
 962
 963 /*
 964  * Function irlap_state_offline (self, event, skb, info)
 965  *
 966  *    OFFLINE state, not used for now!
 967  *
 968  */
 969 static int irlap_state_offline(struct irlap_cb *self, IRLAP_EVENT event,
 970                                struct sk_buff *skb, struct irlap_info *info)
 971 {
 972         IRDA_DEBUG( 0, "%s(), Unknown event\n", __FUNCTION__);
 973
 974         return -1;
 975 }
 976
 977 /*
 978  * Function irlap_state_xmit_p (self, event, skb, info)
 979  *
 980  *    XMIT, Only the primary station has right to transmit, and we
 981  *    therefore do not expect to receive any transmissions from other
 982  *    stations.
 983  *
 984  */
 985 static int irlap_state_xmit_p(struct irlap_cb *self, IRLAP_EVENT event,
 986                               struct sk_buff *skb, struct irlap_info *info)
 987 {
 988         int ret = 0;
 989
 990         switch (event) {
 991         case SEND_I_CMD:
 992                 /*
 993                  *  Only send frame if send-window > 0.
 994                  */
 995                 if ((self->window > 0) && (!self->remote_busy)) {
 996                         int nextfit;
 997 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
 998                         struct sk_buff *skb_next;
 999
1000                         /* With DYNAMIC_WINDOW, we keep the window size
1001                          * maximum, and adapt on the packets we are sending.
1002                          * At 115k, we can send only 2 packets of 2048 bytes
1003                          * in a 500 ms turnaround. Without this option, we
1004                          * would always limit the window to 2. With this
1005                          * option, if we send smaller packets, we can send
1006                          * up to 7 of them (always depending on QoS).
1007                          * Jean II */
1008
1009                         /* Look at the next skb. This is safe, as we are
1010                          * the only consumer of the Tx queue (if we are not,
1011                          * we have other problems) - Jean II */
1012                         skb_next = skb_peek(&self->txq);
1013
1014                         /* Check if a subsequent skb exist and would fit in
1015                          * the current window (with respect to turnaround
1016                          * time).
1017                          * This allow us to properly mark the current packet
1018                          * with the pf bit, to avoid falling back on the
1019                          * second test below, and avoid waiting the
1020                          * end of the window and sending a extra RR.
1021                          * Note : (skb_next != NULL) <=> (skb_queue_len() > 0)
1022                          * Jean II */
1023                         nextfit = ((skb_next != NULL) &&
1024                                    ((skb_next->len + skb->len) <=
1025                                     self->bytes_left));
1026
1027                         /*
1028                          * The current packet may not fit ! Because of test
1029                          * above, this should not happen any more !!!
1030                          *  Test if we have transmitted more bytes over the
1031                          *  link than its possible to do with the current
1032                          *  speed and turn-around-time.
1033                          */
1034                         if((!nextfit) && (skb->len > self->bytes_left)) {
1035                                 IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1036                                            " more bytes!\n", __FUNCTION__);
1037                                 /* Requeue the skb */
1038                                 skb_queue_head(&self->txq, skb_get(skb));
1039                                 /*
1040                                  *  We should switch state to LAP_NRM_P, but
1041                                  *  that is not possible since we must be sure
1042                                  *  that we poll the other side. Since we have
1043                                  *  used up our time, the poll timer should
1044                                  *  trigger anyway now, so we just wait for it
1045                                  *  DB
1046                                  */
1047                                 /*
1048                                  * Sorry, but that's not totally true. If
1049                                  * we send 2000B packets, we may wait another
1050                                  * 1000B until our turnaround expire. That's
1051                                  * why we need to be proactive in avoiding
1052                                  * coming here. - Jean II
1053                                  */
1054                                 return -EPROTO;
1055                         }
1056
1057                         /* Substract space used by this skb */
1058                         self->bytes_left -= skb->len;
1059 #else   /* CONFIG_IRDA_DYNAMIC_WINDOW */
1060                         /* Window has been adjusted for the max packet
1061                          * size, so much simpler... - Jean II */
1062                         nextfit = (skb_queue_len(&self->txq) > 0);
1063 #endif  /* CONFIG_IRDA_DYNAMIC_WINDOW */
1064                         /*
1065                          *  Send data with poll bit cleared only if window > 1
1066                          *  and there is more frames after this one to be sent
1067                          */
1068                         if ((self->window > 1) && (nextfit)) {
1069                                 /* More packet to send in current window */
1070                                 irlap_send_data_primary(self, skb);
1071                                 irlap_next_state(self, LAP_XMIT_P);
1072                         } else {
1073                                 /* Final packet of window */
1074                                 irlap_send_data_primary_poll(self, skb);
1075                                 irlap_next_state(self, LAP_NRM_P);
1076
1077                                 /*
1078                                  * Make sure state machine does not try to send
1079                                  * any more frames
1080                                  */
1081                                 ret = -EPROTO;
1082                         }
1083 #ifdef CONFIG_IRDA_FAST_RR
1084                         /* Peer may want to reply immediately */
1085                         self->fast_RR = FALSE;
1086 #endif /* CONFIG_IRDA_FAST_RR */
1087                 } else {
1088                         IRDA_DEBUG(4, "%s(), Unable to send! remote busy?\n",
1089                                    __FUNCTION__);
1090                         skb_queue_head(&self->txq, skb_get(skb));
1091
1092                         /*
1093                          *  The next ret is important, because it tells
1094                          *  irlap_next_state _not_ to deliver more frames
1095                          */
1096                         ret = -EPROTO;
1097                 }
1098                 break;
1099         case POLL_TIMER_EXPIRED:
1100                 IRDA_DEBUG(3, "%s(), POLL_TIMER_EXPIRED <%ld>\n",
1101                             __FUNCTION__, jiffies);
1102                 irlap_send_rr_frame(self, CMD_FRAME);
1103                 /* Return to NRM properly - Jean II  */
1104                 self->window = self->window_size;
1105 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1106                 /* Allowed to transmit a maximum number of bytes again. */
1107                 self->bytes_left = self->line_capacity;
1108 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1109                 irlap_start_final_timer(self, self->final_timeout);
1110                 irlap_next_state(self, LAP_NRM_P);
1111                 break;
1112         case DISCONNECT_REQUEST:
1113                 del_timer(&self->poll_timer);
1114                 irlap_wait_min_turn_around(self, &self->qos_tx);
1115                 irlap_send_disc_frame(self);
1116                 irlap_flush_all_queues(self);
1117                 irlap_start_final_timer(self, self->final_timeout);
1118                 self->retry_count = 0;
1119                 irlap_next_state(self, LAP_PCLOSE);
1120                 break;
1121         case DATA_REQUEST:
1122                 /* Nothing to do, irlap_do_event() will send the packet
1123                  * when we return... - Jean II */
1124                 break;
1125         default:
1126                 IRDA_DEBUG(0, "%s(), Unknown event %s\n",
1127                            __FUNCTION__, irlap_event[event]);
1128
1129                 ret = -EINVAL;
1130                 break;
1131         }
1132         return ret;
1133 }
1134
1135 /*
1136  * Function irlap_state_pclose (event, skb, info)
1137  *
1138  *    PCLOSE state
1139  */
1140 static int irlap_state_pclose(struct irlap_cb *self, IRLAP_EVENT event,
1141                               struct sk_buff *skb, struct irlap_info *info)
1142 {
1143         int ret = 0;
1144
1145         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
1146
1147         ASSERT(self != NULL, return -1;);
1148         ASSERT(self->magic == LAP_MAGIC, return -1;);
1149
1150         switch (event) {
1151         case RECV_UA_RSP: /* FALLTHROUGH */
1152         case RECV_DM_RSP:
1153                 del_timer(&self->final_timer);
1154
1155                 /* Set new link parameters */
1156                 irlap_apply_default_connection_parameters(self);
1157
1158                 /* Always switch state before calling upper layers */
1159                 irlap_next_state(self, LAP_NDM);
1160
1161                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
1162                 break;
1163         case FINAL_TIMER_EXPIRED:
1164                 if (self->retry_count < self->N3) {
1165                         irlap_wait_min_turn_around(self, &self->qos_tx);
1166                         irlap_send_disc_frame(self);
1167                         irlap_start_final_timer(self, self->final_timeout);
1168                         self->retry_count++;
1169                         /* Keep state */
1170                 } else {
1171                         irlap_apply_default_connection_parameters(self);
1172
1173                         /*  Always switch state before calling upper layers */
1174                         irlap_next_state(self, LAP_NDM);
1175
1176                         irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1177                 }
1178                 break;
1179         default:
1180                 IRDA_DEBUG(1, "%s(), Unknown event %d\n", __FUNCTION__, event);
1181
1182                 ret = -1;
1183                 break;
1184         }
1185         return ret;
1186 }
1187
1188 /*
1189  * Function irlap_state_nrm_p (self, event, skb, info)
1190  *
1191  *   NRM_P (Normal Response Mode as Primary), The primary station has given
1192  *   permissions to a secondary station to transmit IrLAP resonse frames
1193  *   (by sending a frame with the P bit set). The primary station will not
1194  *   transmit any frames and is expecting to receive frames only from the
1195  *   secondary to which transmission permissions has been given.
1196  */
1197 static int irlap_state_nrm_p(struct irlap_cb *self, IRLAP_EVENT event,
1198                              struct sk_buff *skb, struct irlap_info *info)
1199 {
1200         int ret = 0;
1201         int ns_status;
1202         int nr_status;
1203
1204         switch (event) {
1205         case RECV_I_RSP: /* Optimize for the common case */
1206                 /* FIXME: must check for remote_busy below */
1207 #ifdef CONFIG_IRDA_FAST_RR
1208                 /*
1209                  *  Reset the fast_RR so we can use the fast RR code with
1210                  *  full speed the next time since peer may have more frames
1211                  *  to transmitt
1212                  */
1213                 self->fast_RR = FALSE;
1214 #endif /* CONFIG_IRDA_FAST_RR */
1215                 ASSERT( info != NULL, return -1;);
1216
1217                 ns_status = irlap_validate_ns_received(self, info->ns);
1218                 nr_status = irlap_validate_nr_received(self, info->nr);
1219
1220                 /*
1221                  *  Check for expected I(nformation) frame
1222                  */
1223                 if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1224
1225                         /* Update Vr (next frame for us to receive) */
1226                         self->vr = (self->vr + 1) % 8;
1227
1228                         /* Update Nr received, cleanup our retry queue */
1229                         irlap_update_nr_received(self, info->nr);
1230
1231                         /*
1232                          *  Got expected NR, so reset the
1233                          *  retry_count. This is not done by IrLAP spec,
1234                          *  which is strange!
1235                          */
1236                         self->retry_count = 0;
1237                         self->ack_required = TRUE;
1238
1239                         /*  poll bit cleared?  */
1240                         if (!info->pf) {
1241                                 /* Keep state, do not move this line */
1242                                 irlap_next_state(self, LAP_NRM_P);
1243
1244                                 irlap_data_indication(self, skb, FALSE);
1245                         } else {
1246                                 /* No longer waiting for pf */
1247                                 del_timer(&self->final_timer);
1248
1249                                 irlap_wait_min_turn_around(self, &self->qos_tx);
1250
1251                                 /* Call higher layer *before* changing state
1252                                  * to give them a chance to send data in the
1253                                  * next LAP frame.
1254                                  * Jean II */
1255                                 irlap_data_indication(self, skb, FALSE);
1256
1257                                 /* XMIT states are the most dangerous state
1258                                  * to be in, because user requests are
1259                                  * processed directly and may change state.
1260                                  * On the other hand, in NDM_P, those
1261                                  * requests are queued and we will process
1262                                  * them when we return to irlap_do_event().
1263                                  * Jean II
1264                                  */
1265                                 irlap_next_state(self, LAP_XMIT_P);
1266
1267                                 /* This is the last frame.
1268                                  * Make sure it's always called in XMIT state.
1269                                  * - Jean II */
1270                                 irlap_start_poll_timer(self, self->poll_timeout);
1271                         }
1272                         break;
1273
1274                 }
1275                 /* Unexpected next to send (Ns) */
1276                 if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1277                 {
1278                         if (!info->pf) {
1279                                 irlap_update_nr_received(self, info->nr);
1280
1281                                 /*
1282                                  *  Wait until the last frame before doing
1283                                  *  anything
1284                                  */
1285
1286                                 /* Keep state */
1287                                 irlap_next_state(self, LAP_NRM_P);
1288                         } else {
1289                                 IRDA_DEBUG(4,
1290                                        "%s(), missing or duplicate frame!\n",
1291                                            __FUNCTION__);
1292
1293                                 /* Update Nr received */
1294                                 irlap_update_nr_received(self, info->nr);
1295
1296                                 irlap_wait_min_turn_around(self, &self->qos_tx);
1297                                 irlap_send_rr_frame(self, CMD_FRAME);
1298
1299                                 self->ack_required = FALSE;
1300
1301                                 irlap_start_final_timer(self, self->final_timeout);
1302                                 irlap_next_state(self, LAP_NRM_P);
1303                         }
1304                         break;
1305                 }
1306                 /*
1307                  *  Unexpected next to receive (Nr)
1308                  */
1309                 if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1310                 {
1311                         if (info->pf) {
1312                                 self->vr = (self->vr + 1) % 8;
1313
1314                                 /* Update Nr received */
1315                                 irlap_update_nr_received(self, info->nr);
1316
1317                                 /* Resend rejected frames */
1318                                 irlap_resend_rejected_frames(self, CMD_FRAME);
1319
1320                                 self->ack_required = FALSE;
1321
1322                                 /* Make sure we account for the time
1323                                  * to transmit our frames. See comemnts
1324                                  * in irlap_send_data_primary_poll().
1325                                  * Jean II */
1326                                 irlap_start_final_timer(self, 2 * self->final_timeout);
1327
1328                                 /* Keep state, do not move this line */
1329                                 irlap_next_state(self, LAP_NRM_P);
1330
1331                                 irlap_data_indication(self, skb, FALSE);
1332                         } else {
1333                                 /*
1334                                  *  Do not resend frames until the last
1335                                  *  frame has arrived from the other
1336                                  *  device. This is not documented in
1337                                  *  IrLAP!!
1338                                  */
1339                                 self->vr = (self->vr + 1) % 8;
1340
1341                                 /* Update Nr received */
1342                                 irlap_update_nr_received(self, info->nr);
1343
1344                                 self->ack_required = FALSE;
1345
1346                                 /* Keep state, do not move this line!*/
1347                                 irlap_next_state(self, LAP_NRM_P);
1348
1349                                 irlap_data_indication(self, skb, FALSE);
1350                         }
1351                         break;
1352                 }
1353                 /*
1354                  *  Unexpected next to send (Ns) and next to receive (Nr)
1355                  *  Not documented by IrLAP!
1356                  */
1357                 if ((ns_status == NS_UNEXPECTED) &&
1358                     (nr_status == NR_UNEXPECTED))
1359                 {
1360                         IRDA_DEBUG(4, "%s(), unexpected nr and ns!\n",
1361                                    __FUNCTION__);
1362                         if (info->pf) {
1363                                 /* Resend rejected frames */
1364                                 irlap_resend_rejected_frames(self, CMD_FRAME);
1365
1366                                 /* Give peer some time to retransmit!
1367                                  * But account for our own Tx. */
1368                                 irlap_start_final_timer(self, 2 * self->final_timeout);
1369
1370                                 /* Keep state, do not move this line */
1371                                 irlap_next_state(self, LAP_NRM_P);
1372                         } else {
1373                                 /* Update Nr received */
1374                                 /* irlap_update_nr_received( info->nr); */
1375
1376                                 self->ack_required = FALSE;
1377                         }
1378                         break;
1379                 }
1380
1381                 /*
1382                  *  Invalid NR or NS
1383                  */
1384                 if ((nr_status == NR_INVALID) || (ns_status == NS_INVALID)) {
1385                         if (info->pf) {
1386                                 del_timer(&self->final_timer);
1387
1388                                 irlap_next_state(self, LAP_RESET_WAIT);
1389
1390                                 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1391                                 self->xmitflag = TRUE;
1392                         } else {
1393                                 del_timer(&self->final_timer);
1394
1395                                 irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1396
1397                                 self->xmitflag = FALSE;
1398                         }
1399                         break;
1400                 }
1401                 IRDA_DEBUG(1, "%s(), Not implemented!\n", __FUNCTION__);
1402                 IRDA_DEBUG(1, "%s(), event=%s, ns_status=%d, nr_status=%d\n",
1403                        __FUNCTION__, irlap_event[event], ns_status, nr_status);
1404                 break;
1405         case RECV_UI_FRAME:
1406                 /* Poll bit cleared? */
1407                 if (!info->pf) {
1408                         irlap_data_indication(self, skb, TRUE);
1409                         irlap_next_state(self, LAP_NRM_P);
1410                 } else {
1411                         del_timer(&self->final_timer);
1412                         irlap_data_indication(self, skb, TRUE);
1413                         irlap_next_state(self, LAP_XMIT_P);
1414                         IRDA_DEBUG(1, "%s: RECV_UI_FRAME: next state %s\n", __FUNCTION__, irlap_state[self->state]);
1415                         irlap_start_poll_timer(self, self->poll_timeout);
1416                 }
1417                 break;
1418         case RECV_RR_RSP:
1419                 /*
1420                  *  If you get a RR, the remote isn't busy anymore,
1421                  *  no matter what the NR
1422                  */
1423                 self->remote_busy = FALSE;
1424
1425                 /*
1426                  *  Nr as expected?
1427                  */
1428                 ret = irlap_validate_nr_received(self, info->nr);
1429                 if (ret == NR_EXPECTED) {
1430                         /* Stop final timer */
1431                         del_timer(&self->final_timer);
1432
1433                         /* Update Nr received */
1434                         irlap_update_nr_received(self, info->nr);
1435
1436                         /*
1437                          *  Got expected NR, so reset the retry_count. This
1438                          *  is not done by the IrLAP standard , which is
1439                          *  strange! DB.
1440                          */
1441                         self->retry_count = 0;
1442                         irlap_wait_min_turn_around(self, &self->qos_tx);
1443
1444                         irlap_next_state(self, LAP_XMIT_P);
1445
1446                         /* Start poll timer */
1447                         irlap_start_poll_timer(self, self->poll_timeout);
1448                 } else if (ret == NR_UNEXPECTED) {
1449                         ASSERT(info != NULL, return -1;);
1450                         /*
1451                          *  Unexpected nr!
1452                          */
1453
1454                         /* Update Nr received */
1455                         irlap_update_nr_received(self, info->nr);
1456
1457                         IRDA_DEBUG(4, "RECV_RR_FRAME: Retrans:%d, nr=%d, va=%d, "
1458                               "vs=%d, vr=%d\n",
1459                               self->retry_count, info->nr, self->va,
1460                               self->vs, self->vr);
1461
1462                         /* Resend rejected frames */
1463                         irlap_resend_rejected_frames(self, CMD_FRAME);
1464
1465                         /* Final timer ??? Jean II */
1466
1467                         irlap_next_state(self, LAP_NRM_P);
1468                 } else if (ret == NR_INVALID) {
1469                         IRDA_DEBUG(1, "%s(), Received RR with "
1470                                    "invalid nr !\n", __FUNCTION__);
1471                         del_timer(&self->final_timer);
1472
1473                         irlap_next_state(self, LAP_RESET_WAIT);
1474
1475                         irlap_disconnect_indication(self, LAP_RESET_INDICATION);
1476                         self->xmitflag = TRUE;
1477                 }
1478                 break;
1479         case RECV_RNR_RSP:
1480                 ASSERT(info != NULL, return -1;);
1481
1482                 /* Stop final timer */
1483                 del_timer(&self->final_timer);
1484                 self->remote_busy = TRUE;
1485
1486                 /* Update Nr received */
1487                 irlap_update_nr_received(self, info->nr);
1488                 irlap_next_state(self, LAP_XMIT_P);
1489
1490                 /* Start poll timer */
1491                 irlap_start_poll_timer(self, self->poll_timeout);
1492                 break;
1493         case RECV_FRMR_RSP:
1494                 del_timer(&self->final_timer);
1495                 self->xmitflag = TRUE;
1496                 irlap_next_state(self, LAP_RESET_WAIT);
1497                 irlap_reset_indication(self);
1498                 break;
1499         case FINAL_TIMER_EXPIRED:
1500                 /*
1501                  *  We are allowed to wait for additional 300 ms if
1502                  *  final timer expires when we are in the middle
1503                  *  of receiving a frame (page 45, IrLAP). Check that
1504                  *  we only do this once for each frame.
1505                  */
1506                 if (irda_device_is_receiving(self->netdev) && !self->add_wait) {
1507                         IRDA_DEBUG(1, "FINAL_TIMER_EXPIRED when receiving a "
1508                               "frame! Waiting a little bit more!\n");
1509                         irlap_start_final_timer(self, msecs_to_jiffies(300));
1510
1511                         /*
1512                          *  Don't allow this to happen one more time in a row,
1513                          *  or else we can get a pretty tight loop here if
1514                          *  if we only receive half a frame. DB.
1515                          */
1516                         self->add_wait = TRUE;
1517                         break;
1518                 }
1519                 self->add_wait = FALSE;
1520
1521                 /* N2 is the disconnect timer. Until we reach it, we retry */
1522                 if (self->retry_count < self->N2) {
1523                         /* Retry sending the pf bit to the secondary */
1524                         irlap_wait_min_turn_around(self, &self->qos_tx);
1525                         irlap_send_rr_frame(self, CMD_FRAME);
1526
1527                         irlap_start_final_timer(self, self->final_timeout);
1528                         self->retry_count++;
1529                         IRDA_DEBUG(4, "irlap_state_nrm_p: FINAL_TIMER_EXPIRED:"
1530                                    " retry_count=%d\n", self->retry_count);
1531
1532                         /* Early warning event. I'm using a pretty liberal
1533                          * interpretation of the spec and generate an event
1534                          * every time the timer is multiple of N1 (and not
1535                          * only the first time). This allow application
1536                          * to know precisely if connectivity restart...
1537                          * Jean II */
1538                         if((self->retry_count % self->N1) == 0)
1539                                 irlap_status_indication(self,
1540                                                         STATUS_NO_ACTIVITY);
1541
1542                         /* Keep state */
1543                 } else {
1544                         irlap_apply_default_connection_parameters(self);
1545
1546                         /* Always switch state before calling upper layers */
1547                         irlap_next_state(self, LAP_NDM);
1548                         irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1549                 }
1550                 break;
1551         case RECV_REJ_RSP:
1552                 irlap_update_nr_received(self, info->nr);
1553                 if (self->remote_busy) {
1554                         irlap_wait_min_turn_around(self, &self->qos_tx);
1555                         irlap_send_rr_frame(self, CMD_FRAME);
1556                 } else
1557                         irlap_resend_rejected_frames(self, CMD_FRAME);
1558                 irlap_start_final_timer(self, 2 * self->final_timeout);
1559                 break;
1560         case RECV_SREJ_RSP:
1561                 irlap_update_nr_received(self, info->nr);
1562                 if (self->remote_busy) {
1563                         irlap_wait_min_turn_around(self, &self->qos_tx);
1564                         irlap_send_rr_frame(self, CMD_FRAME);
1565                 } else
1566                         irlap_resend_rejected_frame(self, CMD_FRAME);
1567                 irlap_start_final_timer(self, 2 * self->final_timeout);
1568                 break;
1569         case RECV_RD_RSP:
1570                 IRDA_DEBUG(1, "%s(), RECV_RD_RSP\n", __FUNCTION__);
1571
1572                 irlap_flush_all_queues(self);
1573                 irlap_next_state(self, LAP_XMIT_P);
1574                 /* Call back the LAP state machine to do a proper disconnect */
1575                 irlap_disconnect_request(self);
1576                 break;
1577         default:
1578                 IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1579                             __FUNCTION__, irlap_event[event]);
1580
1581                 ret = -1;
1582                 break;
1583         }
1584         return ret;
1585 }
1586
1587 /*
1588  * Function irlap_state_reset_wait (event, skb, info)
1589  *
1590  *    We have informed the service user of a reset condition, and is
1591  *    awaiting reset of disconnect request.
1592  *
1593  */
1594 static int irlap_state_reset_wait(struct irlap_cb *self, IRLAP_EVENT event,
1595                                   struct sk_buff *skb, struct irlap_info *info)
1596 {
1597         int ret = 0;
1598
1599         IRDA_DEBUG(3, "%s(), event = %s\n", __FUNCTION__, irlap_event[event]);
1600
1601         ASSERT(self != NULL, return -1;);
1602         ASSERT(self->magic == LAP_MAGIC, return -1;);
1603
1604         switch (event) {
1605         case RESET_REQUEST:
1606                 if (self->xmitflag) {
1607                         irlap_wait_min_turn_around(self, &self->qos_tx);
1608                         irlap_send_snrm_frame(self, NULL);
1609                         irlap_start_final_timer(self, self->final_timeout);
1610                         irlap_next_state(self, LAP_RESET);
1611                 } else {
1612                         irlap_start_final_timer(self, self->final_timeout);
1613                         irlap_next_state(self, LAP_RESET);
1614                 }
1615                 break;
1616         case DISCONNECT_REQUEST:
1617                 irlap_wait_min_turn_around( self, &self->qos_tx);
1618                 irlap_send_disc_frame( self);
1619                 irlap_flush_all_queues( self);
1620                 irlap_start_final_timer( self, self->final_timeout);
1621                 self->retry_count = 0;
1622                 irlap_next_state( self, LAP_PCLOSE);
1623                 break;
1624         default:
1625                 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
1626                            irlap_event[event]);
1627
1628                 ret = -1;
1629                 break;
1630         }
1631         return ret;
1632 }
1633
1634 /*
1635  * Function irlap_state_reset (self, event, skb, info)
1636  *
1637  *    We have sent a SNRM reset command to the peer layer, and is awaiting
1638  *    reply.
1639  *
1640  */
1641 static int irlap_state_reset(struct irlap_cb *self, IRLAP_EVENT event,
1642                              struct sk_buff *skb, struct irlap_info *info)
1643 {
1644         int ret = 0;
1645
1646         IRDA_DEBUG(3, "%s(), event = %s\n", __FUNCTION__, irlap_event[event]);
1647
1648         ASSERT(self != NULL, return -1;);
1649         ASSERT(self->magic == LAP_MAGIC, return -1;);
1650
1651         switch (event) {
1652         case RECV_DISC_CMD:
1653                 del_timer(&self->final_timer);
1654
1655                 irlap_apply_default_connection_parameters(self);
1656
1657                 /* Always switch state before calling upper layers */
1658                 irlap_next_state(self, LAP_NDM);
1659
1660                 irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1661
1662                 break;
1663         case RECV_UA_RSP:
1664                 del_timer(&self->final_timer);
1665
1666                 /* Initiate connection state */
1667                 irlap_initiate_connection_state(self);
1668
1669                 irlap_reset_confirm();
1670
1671                 self->remote_busy = FALSE;
1672
1673                 irlap_next_state(self, LAP_XMIT_P);
1674
1675                 irlap_start_poll_timer(self, self->poll_timeout);
1676
1677                 break;
1678         case FINAL_TIMER_EXPIRED:
1679                 if (self->retry_count < 3) {
1680                         irlap_wait_min_turn_around(self, &self->qos_tx);
1681
1682                         ASSERT(self->netdev != NULL, return -1;);
1683                         irlap_send_snrm_frame(self, self->qos_dev);
1684
1685                         self->retry_count++; /* Experimental!! */
1686
1687                         irlap_start_final_timer(self, self->final_timeout);
1688                         irlap_next_state(self, LAP_RESET);
1689                 } else if (self->retry_count >= self->N3) {
1690                         irlap_apply_default_connection_parameters(self);
1691
1692                         /* Always switch state before calling upper layers */
1693                         irlap_next_state(self, LAP_NDM);
1694
1695                         irlap_disconnect_indication(self, LAP_NO_RESPONSE);
1696                 }
1697                 break;
1698         case RECV_SNRM_CMD:
1699                 /*
1700                  * SNRM frame is not allowed to contain an I-field in this
1701                  * state
1702                  */
1703                 if (!info) {
1704                         IRDA_DEBUG(3, "%s(), RECV_SNRM_CMD\n", __FUNCTION__);
1705                         irlap_initiate_connection_state(self);
1706                         irlap_wait_min_turn_around(self, &self->qos_tx);
1707                         irlap_send_ua_response_frame(self, &self->qos_rx);
1708                         irlap_reset_confirm();
1709                         irlap_start_wd_timer(self, self->wd_timeout);
1710                         irlap_next_state(self, LAP_NDM);
1711                 } else {
1712                         IRDA_DEBUG(0,
1713                                    "%s(), SNRM frame contained an I field!\n",
1714                                    __FUNCTION__);
1715                 }
1716                 break;
1717         default:
1718                 IRDA_DEBUG(1, "%s(), Unknown event %s\n",
1719                            __FUNCTION__, irlap_event[event]);
1720
1721                 ret = -1;
1722                 break;
1723         }
1724         return ret;
1725 }
1726
1727 /*
1728  * Function irlap_state_xmit_s (event, skb, info)
1729  *
1730  *   XMIT_S, The secondary station has been given the right to transmit,
1731  *   and we therefor do not expect to receive any transmissions from other
1732  *   stations.
1733  */
1734 static int irlap_state_xmit_s(struct irlap_cb *self, IRLAP_EVENT event,
1735                               struct sk_buff *skb, struct irlap_info *info)
1736 {
1737         int ret = 0;
1738
1739         IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[event]);
1740
1741         ASSERT(self != NULL, return -ENODEV;);
1742         ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
1743
1744         switch (event) {
1745         case SEND_I_CMD:
1746                 /*
1747                  *  Send frame only if send window > 0
1748                  */
1749                 if ((self->window > 0) && (!self->remote_busy)) {
1750                         int nextfit;
1751 #ifdef CONFIG_IRDA_DYNAMIC_WINDOW
1752                         struct sk_buff *skb_next;
1753
1754                         /*
1755                          * Same deal as in irlap_state_xmit_p(), so see
1756                          * the comments at that point.
1757                          * We are the secondary, so there are only subtle
1758                          * differences. - Jean II
1759                          */
1760
1761                         /* Check if a subsequent skb exist and would fit in
1762                          * the current window (with respect to turnaround
1763                          * time). - Jean II */
1764                         skb_next = skb_peek(&self->txq);
1765                         nextfit = ((skb_next != NULL) &&
1766                                    ((skb_next->len + skb->len) <=
1767                                     self->bytes_left));
1768
1769                         /*
1770                          *  Test if we have transmitted more bytes over the
1771                          *  link than its possible to do with the current
1772                          *  speed and turn-around-time.
1773                          */
1774                         if((!nextfit) && (skb->len > self->bytes_left)) {
1775                                 IRDA_DEBUG(0, "%s(), Not allowed to transmit"
1776                                            " more bytes!\n", __FUNCTION__);
1777                                 /* Requeue the skb */
1778                                 skb_queue_head(&self->txq, skb_get(skb));
1779
1780                                 /*
1781                                  *  Switch to NRM_S, this is only possible
1782                                  *  when we are in secondary mode, since we
1783                                  *  must be sure that we don't miss any RR
1784                                  *  frames
1785                                  */
1786                                 self->window = self->window_size;
1787                                 self->bytes_left = self->line_capacity;
1788                                 irlap_start_wd_timer(self, self->wd_timeout);
1789
1790                                 irlap_next_state(self, LAP_NRM_S);
1791                                 /* Slight difference with primary :
1792                                  * here we would wait for the other side to
1793                                  * expire the turnaround. - Jean II */
1794
1795                                 return -EPROTO; /* Try again later */
1796                         }
1797                         /* Substract space used by this skb */
1798                         self->bytes_left -= skb->len;
1799 #else   /* CONFIG_IRDA_DYNAMIC_WINDOW */
1800                         /* Window has been adjusted for the max packet
1801                          * size, so much simpler... - Jean II */
1802                         nextfit = (skb_queue_len(&self->txq) > 0);
1803 #endif /* CONFIG_IRDA_DYNAMIC_WINDOW */
1804                         /*
1805                          *  Send data with final bit cleared only if window > 1
1806                          *  and there is more frames to be sent
1807                          */
1808                         if ((self->window > 1) && (nextfit)) {
1809                                 irlap_send_data_secondary(self, skb);
1810                                 irlap_next_state(self, LAP_XMIT_S);
1811                         } else {
1812                                 irlap_send_data_secondary_final(self, skb);
1813                                 irlap_next_state(self, LAP_NRM_S);
1814
1815                                 /*
1816                                  * Make sure state machine does not try to send
1817                                  * any more frames
1818                                  */
1819                                 ret = -EPROTO;
1820                         }
1821                 } else {
1822                         IRDA_DEBUG(2, "%s(), Unable to send!\n", __FUNCTION__);
1823                         skb_queue_head(&self->txq, skb_get(skb));
1824                         ret = -EPROTO;
1825                 }
1826                 break;
1827         case DISCONNECT_REQUEST:
1828                 irlap_send_rd_frame(self);
1829                 irlap_flush_all_queues(self);
1830                 irlap_start_wd_timer(self, self->wd_timeout);
1831                 irlap_next_state(self, LAP_SCLOSE);
1832                 break;
1833         case DATA_REQUEST:
1834                 /* Nothing to do, irlap_do_event() will send the packet
1835                  * when we return... - Jean II */
1836                 break;
1837         default:
1838                 IRDA_DEBUG(2, "%s(), Unknown event %s\n", __FUNCTION__,
1839                            irlap_event[event]);
1840
1841                 ret = -EINVAL;
1842                 break;
1843         }
1844         return ret;
1845 }
1846
1847 /*
1848  * Function irlap_state_nrm_s (event, skb, info)
1849  *
1850  *    NRM_S (Normal Response Mode as Secondary) state, in this state we are
1851  *    expecting to receive frames from the primary station
1852  *
1853  */
1854 static int irlap_state_nrm_s(struct irlap_cb *self, IRLAP_EVENT event,
1855                              struct sk_buff *skb, struct irlap_info *info)
1856 {
1857         int ns_status;
1858         int nr_status;
1859         int ret = 0;
1860
1861         IRDA_DEBUG(4, "%s(), event=%s\n", __FUNCTION__, irlap_event[ event]);
1862
1863         ASSERT(self != NULL, return -1;);
1864         ASSERT(self->magic == LAP_MAGIC, return -1;);
1865
1866         switch (event) {
1867         case RECV_I_CMD: /* Optimize for the common case */
1868                 /* FIXME: must check for remote_busy below */
1869                 IRDA_DEBUG(4, "%s(), event=%s nr=%d, vs=%d, ns=%d, "
1870                            "vr=%d, pf=%d\n", __FUNCTION__,
1871                            irlap_event[event], info->nr,
1872                            self->vs, info->ns, self->vr, info->pf);
1873
1874                 self->retry_count = 0;
1875
1876                 ns_status = irlap_validate_ns_received(self, info->ns);
1877                 nr_status = irlap_validate_nr_received(self, info->nr);
1878                 /*
1879                  *  Check for expected I(nformation) frame
1880                  */
1881                 if ((ns_status == NS_EXPECTED) && (nr_status == NR_EXPECTED)) {
1882
1883                         /* Update Vr (next frame for us to receive) */
1884                         self->vr = (self->vr + 1) % 8;
1885
1886                         /* Update Nr received */
1887                         irlap_update_nr_received(self, info->nr);
1888
1889                         /*
1890                          *  poll bit cleared?
1891                          */
1892                         if (!info->pf) {
1893
1894                                 self->ack_required = TRUE;
1895
1896                                 /*
1897                                  *  Starting WD-timer here is optional, but
1898                                  *  not recommended. Note 6 IrLAP p. 83
1899                                  */
1900 #if 0
1901                                 irda_start_timer(WD_TIMER, self->wd_timeout);
1902 #endif
1903                                 /* Keep state, do not move this line */
1904                                 irlap_next_state(self, LAP_NRM_S);
1905
1906                                 irlap_data_indication(self, skb, FALSE);
1907                                 break;
1908                         } else {
1909                                 /*
1910                                  *  We should wait before sending RR, and
1911                                  *  also before changing to XMIT_S
1912                                  *  state. (note 1, IrLAP p. 82)
1913                                  */
1914                                 irlap_wait_min_turn_around(self, &self->qos_tx);
1915
1916                                 /*
1917                                  * Give higher layers a chance to
1918                                  * immediately reply with some data before
1919                                  * we decide if we should send a RR frame
1920                                  * or not
1921                                  */
1922                                 irlap_data_indication(self, skb, FALSE);
1923
1924                                 /* Any pending data requests?  */
1925                                 if ((skb_queue_len(&self->txq) > 0) &&
1926                                     (self->window > 0))
1927                                 {
1928                                         self->ack_required = TRUE;
1929
1930                                         del_timer(&self->wd_timer);
1931
1932                                         irlap_next_state(self, LAP_XMIT_S);
1933                                 } else {
1934                                         irlap_send_rr_frame(self, RSP_FRAME);
1935                                         irlap_start_wd_timer(self,
1936                                                              self->wd_timeout);
1937
1938                                         /* Keep the state */
1939                                         irlap_next_state(self, LAP_NRM_S);
1940                                 }
1941                                 break;
1942                         }
1943                 }
1944                 /*
1945                  *  Check for Unexpected next to send (Ns)
1946                  */
1947                 if ((ns_status == NS_UNEXPECTED) && (nr_status == NR_EXPECTED))
1948                 {
1949                         /* Unexpected next to send, with final bit cleared */
1950                         if (!info->pf) {
1951                                 irlap_update_nr_received(self, info->nr);
1952
1953                                 irlap_start_wd_timer(self, self->wd_timeout);
1954                         } else {
1955                                 /* Update Nr received */
1956                                 irlap_update_nr_received(self, info->nr);
1957
1958                                 irlap_wait_min_turn_around(self, &self->qos_tx);
1959                                 irlap_send_rr_frame(self, RSP_FRAME);
1960
1961                                 irlap_start_wd_timer(self, self->wd_timeout);
1962                         }
1963                         break;
1964                 }
1965
1966                 /*
1967                  *  Unexpected Next to Receive(NR) ?
1968                  */
1969                 if ((ns_status == NS_EXPECTED) && (nr_status == NR_UNEXPECTED))
1970                 {
1971                         if (info->pf) {
1972                                 IRDA_DEBUG(4, "RECV_I_RSP: frame(s) lost\n");
1973
1974                                 self->vr = (self->vr + 1) % 8;
1975
1976                                 /* Update Nr received */
1977                                 irlap_update_nr_received(self, info->nr);
1978
1979                                 /* Resend rejected frames */
1980                                 irlap_resend_rejected_frames(self, RSP_FRAME);
1981
1982                                 /* Keep state, do not move this line */
1983                                 irlap_next_state(self, LAP_NRM_S);
1984
1985                                 irlap_data_indication(self, skb, FALSE);
1986                                 irlap_start_wd_timer(self, self->wd_timeout);
1987                                 break;
1988                         }
1989                         /*
1990                          *  This is not documented in IrLAP!! Unexpected NR
1991                          *  with poll bit cleared
1992                          */
1993                         if (!info->pf) {
1994                                 self->vr = (self->vr + 1) % 8;
1995
1996                                 /* Update Nr received */
1997                                 irlap_update_nr_received(self, info->nr);
1998
1999                                 /* Keep state, do not move this line */
2000                                 irlap_next_state(self, LAP_NRM_S);
2001
2002                                 irlap_data_indication(self, skb, FALSE);
2003                                 irlap_start_wd_timer(self, self->wd_timeout);
2004                         }
2005                         break;
2006                 }
2007
2008                 if (ret == NR_INVALID) {
2009                         IRDA_DEBUG(0, "NRM_S, NR_INVALID not implemented!\n");
2010                 }
2011                 if (ret == NS_INVALID) {
2012                         IRDA_DEBUG(0, "NRM_S, NS_INVALID not implemented!\n");
2013                 }
2014                 break;
2015         case RECV_UI_FRAME:
2016                 /*
2017                  *  poll bit cleared?
2018                  */
2019                 if (!info->pf) {
2020                         irlap_data_indication(self, skb, TRUE);
2021                         irlap_next_state(self, LAP_NRM_S); /* Keep state */
2022                 } else {
2023                         /*
2024                          *  Any pending data requests?
2025                          */
2026                         if ((skb_queue_len(&self->txq) > 0) &&
2027                             (self->window > 0) && !self->remote_busy)
2028                         {
2029                                 irlap_data_indication(self, skb, TRUE);
2030
2031                                 del_timer(&self->wd_timer);
2032
2033                                 irlap_next_state(self, LAP_XMIT_S);
2034                         } else {
2035                                 irlap_data_indication(self, skb, TRUE);
2036
2037                                 irlap_wait_min_turn_around(self, &self->qos_tx);
2038
2039                                 irlap_send_rr_frame(self, RSP_FRAME);
2040                                 self->ack_required = FALSE;
2041
2042                                 irlap_start_wd_timer(self, self->wd_timeout);
2043
2044                                 /* Keep the state */
2045                                 irlap_next_state(self, LAP_NRM_S);
2046                         }
2047                 }
2048                 break;
2049         case RECV_RR_CMD:
2050                 self->retry_count = 0;
2051
2052                 /*
2053                  *  Nr as expected?
2054                  */
2055                 nr_status = irlap_validate_nr_received(self, info->nr);
2056                 if (nr_status == NR_EXPECTED) {
2057                         if ((skb_queue_len( &self->txq) > 0) &&
2058                             (self->window > 0)) {
2059                                 self->remote_busy = FALSE;
2060
2061                                 /* Update Nr received */
2062                                 irlap_update_nr_received(self, info->nr);
2063                                 del_timer(&self->wd_timer);
2064
2065                                 irlap_wait_min_turn_around(self, &self->qos_tx);
2066                                 irlap_next_state(self, LAP_XMIT_S);
2067                         } else {
2068                                 self->remote_busy = FALSE;
2069                                 /* Update Nr received */
2070                                 irlap_update_nr_received(self, info->nr);
2071                                 irlap_wait_min_turn_around(self, &self->qos_tx);
2072                                 irlap_start_wd_timer(self, self->wd_timeout);
2073
2074                                 /* Note : if the link is idle (this case),
2075                                  * we never go in XMIT_S, so we never get a
2076                                  * chance to process any DISCONNECT_REQUEST.
2077                                  * Do it now ! - Jean II */
2078                                 if (self->disconnect_pending) {
2079                                         /* Disconnect */
2080                                         irlap_send_rd_frame(self);
2081                                         irlap_flush_all_queues(self);
2082
2083                                         irlap_next_state(self, LAP_SCLOSE);
2084                                 } else {
2085                                         /* Just send back pf bit */
2086                                         irlap_send_rr_frame(self, RSP_FRAME);
2087
2088                                         irlap_next_state(self, LAP_NRM_S);
2089                                 }
2090                         }
2091                 } else if (nr_status == NR_UNEXPECTED) {
2092                         self->remote_busy = FALSE;
2093                         irlap_update_nr_received(self, info->nr);
2094                         irlap_resend_rejected_frames(self, RSP_FRAME);
2095
2096                         irlap_start_wd_timer(self, self->wd_timeout);
2097
2098                         /* Keep state */
2099                         irlap_next_state(self, LAP_NRM_S);
2100                 } else {
2101                         IRDA_DEBUG(1, "%s(), invalid nr not implemented!\n",
2102                                    __FUNCTION__);
2103                 }
2104                 break;
2105         case RECV_SNRM_CMD:
2106                 /* SNRM frame is not allowed to contain an I-field */
2107                 if (!info) {
2108                         del_timer(&self->wd_timer);
2109                         IRDA_DEBUG(1, "%s(), received SNRM cmd\n", __FUNCTION__);
2110                         irlap_next_state(self, LAP_RESET_CHECK);
2111
2112                         irlap_reset_indication(self);
2113                 } else {
2114                         IRDA_DEBUG(0,
2115                                    "%s(), SNRM frame contained an I-field!\n",
2116                                    __FUNCTION__);
2117
2118                 }
2119                 break;
2120         case RECV_REJ_CMD:
2121                 irlap_update_nr_received(self, info->nr);
2122                 if (self->remote_busy) {
2123                         irlap_wait_min_turn_around(self, &self->qos_tx);
2124                         irlap_send_rr_frame(self, RSP_FRAME);
2125                 } else
2126                         irlap_resend_rejected_frames(self, RSP_FRAME);
2127                 irlap_start_wd_timer(self, self->wd_timeout);
2128                 break;
2129         case RECV_SREJ_CMD:
2130                 irlap_update_nr_received(self, info->nr);
2131                 if (self->remote_busy) {
2132                         irlap_wait_min_turn_around(self, &self->qos_tx);
2133                         irlap_send_rr_frame(self, RSP_FRAME);
2134                 } else
2135                         irlap_resend_rejected_frame(self, RSP_FRAME);
2136                 irlap_start_wd_timer(self, self->wd_timeout);
2137                 break;
2138         case WD_TIMER_EXPIRED:
2139                 /*
2140                  *  Wait until retry_count * n matches negotiated threshold/
2141                  *  disconnect time (note 2 in IrLAP p. 82)
2142                  *
2143                  * Similar to irlap_state_nrm_p() -> FINAL_TIMER_EXPIRED
2144                  * Note : self->wd_timeout = (self->final_timeout * 2),
2145                  *   which explain why we use (self->N2 / 2) here !!!
2146                  * Jean II
2147                  */
2148                 IRDA_DEBUG(1, "%s(), retry_count = %d\n", __FUNCTION__,
2149                            self->retry_count);
2150
2151                 if (self->retry_count < (self->N2 / 2)) {
2152                         /* No retry, just wait for primary */
2153                         irlap_start_wd_timer(self, self->wd_timeout);
2154                         self->retry_count++;
2155
2156                         if((self->retry_count % (self->N1 / 2)) == 0)
2157                                 irlap_status_indication(self,
2158                                                         STATUS_NO_ACTIVITY);
2159                 } else {
2160                         irlap_apply_default_connection_parameters(self);
2161
2162                         /* Always switch state before calling upper layers */
2163                         irlap_next_state(self, LAP_NDM);
2164                         irlap_disconnect_indication(self, LAP_NO_RESPONSE);
2165                 }
2166                 break;
2167         case RECV_DISC_CMD:
2168                 /* Always switch state before calling upper layers */
2169                 irlap_next_state(self, LAP_NDM);
2170
2171                 /* Send disconnect response */
2172                 irlap_wait_min_turn_around(self, &self->qos_tx);
2173                 irlap_send_ua_response_frame(self, NULL);
2174
2175                 del_timer(&self->wd_timer);
2176                 irlap_flush_all_queues(self);
2177                 /* Set default link parameters */
2178                 irlap_apply_default_connection_parameters(self);
2179
2180                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2181                 break;
2182         case RECV_DISCOVERY_XID_CMD:
2183                 irlap_wait_min_turn_around(self, &self->qos_tx);
2184                 irlap_send_rr_frame(self, RSP_FRAME);
2185                 self->ack_required = TRUE;
2186                 irlap_start_wd_timer(self, self->wd_timeout);
2187                 irlap_next_state(self, LAP_NRM_S);
2188
2189                 break;
2190         case RECV_TEST_CMD:
2191                 /* Remove test frame header (only LAP header in NRM) */
2192                 skb_pull(skb, LAP_ADDR_HEADER + LAP_CTRL_HEADER);
2193
2194                 irlap_wait_min_turn_around(self, &self->qos_tx);
2195                 irlap_start_wd_timer(self, self->wd_timeout);
2196
2197                 /* Send response (info will be copied) */
2198                 irlap_send_test_frame(self, self->caddr, info->daddr, skb);
2199                 break;
2200         default:
2201                 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2202                            event, irlap_event[event]);
2203
2204                 ret = -EINVAL;
2205                 break;
2206         }
2207         return ret;
2208 }
2209
2210 /*
2211  * Function irlap_state_sclose (self, event, skb, info)
2212  */
2213 static int irlap_state_sclose(struct irlap_cb *self, IRLAP_EVENT event,
2214                               struct sk_buff *skb, struct irlap_info *info)
2215 {
2216         int ret = 0;
2217
2218         IRDA_DEBUG(1, "%s()\n", __FUNCTION__);
2219
2220         ASSERT(self != NULL, return -ENODEV;);
2221         ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2222
2223         switch (event) {
2224         case RECV_DISC_CMD:
2225                 /* Always switch state before calling upper layers */
2226                 irlap_next_state(self, LAP_NDM);
2227
2228                 /* Send disconnect response */
2229                 irlap_wait_min_turn_around(self, &self->qos_tx);
2230                 irlap_send_ua_response_frame(self, NULL);
2231
2232                 del_timer(&self->wd_timer);
2233                 /* Set default link parameters */
2234                 irlap_apply_default_connection_parameters(self);
2235
2236                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2237                 break;
2238         case RECV_DM_RSP:
2239                 /* IrLAP-1.1 p.82: in SCLOSE, S and I type RSP frames
2240                  * shall take us down into default NDM state, like DM_RSP
2241                  */
2242         case RECV_RR_RSP:
2243         case RECV_RNR_RSP:
2244         case RECV_REJ_RSP:
2245         case RECV_SREJ_RSP:
2246         case RECV_I_RSP:
2247                 /* Always switch state before calling upper layers */
2248                 irlap_next_state(self, LAP_NDM);
2249
2250                 del_timer(&self->wd_timer);
2251                 irlap_apply_default_connection_parameters(self);
2252
2253                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2254                 break;
2255         case WD_TIMER_EXPIRED:
2256                 /* Always switch state before calling upper layers */
2257                 irlap_next_state(self, LAP_NDM);
2258
2259                 irlap_apply_default_connection_parameters(self);
2260
2261                 irlap_disconnect_indication(self, LAP_DISC_INDICATION);
2262                 break;
2263         default:
2264                 /* IrLAP-1.1 p.82: in SCLOSE, basically any received frame
2265                  * with pf=1 shall restart the wd-timer and resend the rd:rsp
2266                  */
2267                 if (info != NULL  &&  info->pf) {
2268                         del_timer(&self->wd_timer);
2269                         irlap_wait_min_turn_around(self, &self->qos_tx);
2270                         irlap_send_rd_frame(self);
2271                         irlap_start_wd_timer(self, self->wd_timeout);
2272                         break;          /* stay in SCLOSE */
2273                 }
2274
2275                 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2276                            event, irlap_event[event]);
2277
2278                 ret = -EINVAL;
2279                 break;
2280         }
2281
2282         return -1;
2283 }
2284
2285 static int irlap_state_reset_check( struct irlap_cb *self, IRLAP_EVENT event,
2286                                    struct sk_buff *skb,
2287                                    struct irlap_info *info)
2288 {
2289         int ret = 0;
2290
2291         IRDA_DEBUG(1, "%s(), event=%s\n", __FUNCTION__, irlap_event[event]);
2292
2293         ASSERT(self != NULL, return -ENODEV;);
2294         ASSERT(self->magic == LAP_MAGIC, return -EBADR;);
2295
2296         switch (event) {
2297         case RESET_RESPONSE:
2298                 irlap_send_ua_response_frame(self, &self->qos_rx);
2299                 irlap_initiate_connection_state(self);
2300                 irlap_start_wd_timer(self, WD_TIMEOUT);
2301                 irlap_flush_all_queues(self);
2302
2303                 irlap_next_state(self, LAP_NRM_S);
2304                 break;
2305         case DISCONNECT_REQUEST:
2306                 irlap_wait_min_turn_around(self, &self->qos_tx);
2307                 irlap_send_rd_frame(self);
2308                 irlap_start_wd_timer(self, WD_TIMEOUT);
2309                 irlap_next_state(self, LAP_SCLOSE);
2310                 break;
2311         default:
2312                 IRDA_DEBUG(1, "%s(), Unknown event %d, (%s)\n", __FUNCTION__,
2313                            event, irlap_event[event]);
2314
2315                 ret = -EINVAL;
2316                 break;
2317         }
2318         return ret;
2319 }