kernel/drivers/isdn/gigaset/common.c

   1 /*
   2  * Stuff used by all variants of the driver
   3  *
   4  * Copyright (c) 2001 by Stefan Eilers,
   5  *                       Hansjoerg Lipp <hjlipp@web.de>,
   6  *                       Tilman Schmidt <tilman@imap.cc>.
   7  *
   8  * =====================================================================
   9  *      This program is free software; you can redistribute it and/or
  10  *      modify it under the terms of the GNU General Public License as
  11  *      published by the Free Software Foundation; either version 2 of
  12  *      the License, or (at your option) any later version.
  13  * =====================================================================
  14  */
  15
  16 #include "gigaset.h"
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19
  20 /* Version Information */
  21 #define DRIVER_AUTHOR "Hansjoerg Lipp <hjlipp@web.de>, Tilman Schmidt <tilman@imap.cc>, Stefan Eilers"
  22 #define DRIVER_DESC "Driver for Gigaset 307x"
  23
  24 #ifdef CONFIG_GIGASET_DEBUG
  25 #define DRIVER_DESC_DEBUG " (debug build)"
  26 #else
  27 #define DRIVER_DESC_DEBUG ""
  28 #endif
  29
  30 /* Module parameters */
  31 int gigaset_debuglevel;
  32 EXPORT_SYMBOL_GPL(gigaset_debuglevel);
  33 module_param_named(debug, gigaset_debuglevel, int, S_IRUGO | S_IWUSR);
  34 MODULE_PARM_DESC(debug, "debug level");
  35
  36 /* driver state flags */
  37 #define VALID_MINOR     0x01
  38 #define VALID_ID        0x02
  39
  40 /**
  41  * gigaset_dbg_buffer() - dump data in ASCII and hex for debugging
  42  * @level:      debugging level.
  43  * @msg:        message prefix.
  44  * @len:        number of bytes to dump.
  45  * @buf:        data to dump.
  46  *
  47  * If the current debugging level includes one of the bits set in @level,
  48  * @len bytes starting at @buf are logged to dmesg at KERN_DEBUG prio,
  49  * prefixed by the text @msg.
  50  */
  51 void gigaset_dbg_buffer(enum debuglevel level, const unsigned char *msg,
  52                         size_t len, const unsigned char *buf)
  53 {
  54         unsigned char outbuf[80];
  55         unsigned char c;
  56         size_t space = sizeof outbuf - 1;
  57         unsigned char *out = outbuf;
  58         size_t numin = len;
  59
  60         while (numin--) {
  61                 c = *buf++;
  62                 if (c == '~' || c == '^' || c == '\\') {
  63                         if (!space--)
  64                                 break;
  65                         *out++ = '\\';
  66                 }
  67                 if (c & 0x80) {
  68                         if (!space--)
  69                                 break;
  70                         *out++ = '~';
  71                         c ^= 0x80;
  72                 }
  73                 if (c < 0x20 || c == 0x7f) {
  74                         if (!space--)
  75                                 break;
  76                         *out++ = '^';
  77                         c ^= 0x40;
  78                 }
  79                 if (!space--)
  80                         break;
  81                 *out++ = c;
  82         }
  83         *out = 0;
  84
  85         gig_dbg(level, "%s (%u bytes): %s", msg, (unsigned) len, outbuf);
  86 }
  87 EXPORT_SYMBOL_GPL(gigaset_dbg_buffer);
  88
  89 static int setflags(struct cardstate *cs, unsigned flags, unsigned delay)
  90 {
  91         int r;
  92
  93         r = cs->ops->set_modem_ctrl(cs, cs->control_state, flags);
  94         cs->control_state = flags;
  95         if (r < 0)
  96                 return r;
  97
  98         if (delay) {
  99                 set_current_state(TASK_INTERRUPTIBLE);
 100                 schedule_timeout(delay * HZ / 1000);
 101         }
 102
 103         return 0;
 104 }
 105
 106 int gigaset_enterconfigmode(struct cardstate *cs)
 107 {
 108         int i, r;
 109
 110         cs->control_state = TIOCM_RTS;
 111
 112         r = setflags(cs, TIOCM_DTR, 200);
 113         if (r < 0)
 114                 goto error;
 115         r = setflags(cs, 0, 200);
 116         if (r < 0)
 117                 goto error;
 118         for (i = 0; i < 5; ++i) {
 119                 r = setflags(cs, TIOCM_RTS, 100);
 120                 if (r < 0)
 121                         goto error;
 122                 r = setflags(cs, 0, 100);
 123                 if (r < 0)
 124                         goto error;
 125         }
 126         r = setflags(cs, TIOCM_RTS | TIOCM_DTR, 800);
 127         if (r < 0)
 128                 goto error;
 129
 130         return 0;
 131
 132 error:
 133         dev_err(cs->dev, "error %d on setuartbits\n", -r);
 134         cs->control_state = TIOCM_RTS | TIOCM_DTR;
 135         cs->ops->set_modem_ctrl(cs, 0, TIOCM_RTS | TIOCM_DTR);
 136
 137         return -1;
 138 }
 139
 140 static int test_timeout(struct at_state_t *at_state)
 141 {
 142         if (!at_state->timer_expires)
 143                 return 0;
 144
 145         if (--at_state->timer_expires) {
 146                 gig_dbg(DEBUG_MCMD, "decreased timer of %p to %lu",
 147                         at_state, at_state->timer_expires);
 148                 return 0;
 149         }
 150
 151         gigaset_add_event(at_state->cs, at_state, EV_TIMEOUT, NULL,
 152                           at_state->timer_index, NULL);
 153         return 1;
 154 }
 155
 156 static void timer_tick(unsigned long data)
 157 {
 158         struct cardstate *cs = (struct cardstate *) data;
 159         unsigned long flags;
 160         unsigned channel;
 161         struct at_state_t *at_state;
 162         int timeout = 0;
 163
 164         spin_lock_irqsave(&cs->lock, flags);
 165
 166         for (channel = 0; channel < cs->channels; ++channel)
 167                 if (test_timeout(&cs->bcs[channel].at_state))
 168                         timeout = 1;
 169
 170         if (test_timeout(&cs->at_state))
 171                 timeout = 1;
 172
 173         list_for_each_entry(at_state, &cs->temp_at_states, list)
 174                 if (test_timeout(at_state))
 175                         timeout = 1;
 176
 177         if (cs->running) {
 178                 mod_timer(&cs->timer, jiffies + msecs_to_jiffies(GIG_TICK));
 179                 if (timeout) {
 180                         gig_dbg(DEBUG_EVENT, "scheduling timeout");
 181                         tasklet_schedule(&cs->event_tasklet);
 182                 }
 183         }
 184
 185         spin_unlock_irqrestore(&cs->lock, flags);
 186 }
 187
 188 int gigaset_get_channel(struct bc_state *bcs)
 189 {
 190         unsigned long flags;
 191
 192         spin_lock_irqsave(&bcs->cs->lock, flags);
 193         if (bcs->use_count || !try_module_get(bcs->cs->driver->owner)) {
 194                 gig_dbg(DEBUG_CHANNEL, "could not allocate channel %d",
 195                         bcs->channel);
 196                 spin_unlock_irqrestore(&bcs->cs->lock, flags);
 197                 return -EBUSY;
 198         }
 199         ++bcs->use_count;
 200         bcs->busy = 1;
 201         gig_dbg(DEBUG_CHANNEL, "allocated channel %d", bcs->channel);
 202         spin_unlock_irqrestore(&bcs->cs->lock, flags);
 203         return 0;
 204 }
 205
 206 struct bc_state *gigaset_get_free_channel(struct cardstate *cs)
 207 {
 208         unsigned long flags;
 209         int i;
 210
 211         spin_lock_irqsave(&cs->lock, flags);
 212         if (!try_module_get(cs->driver->owner)) {
 213                 gig_dbg(DEBUG_CHANNEL,
 214                         "could not get module for allocating channel");
 215                 spin_unlock_irqrestore(&cs->lock, flags);
 216                 return NULL;
 217         }
 218         for (i = 0; i < cs->channels; ++i)
 219                 if (!cs->bcs[i].use_count) {
 220                         ++cs->bcs[i].use_count;
 221                         cs->bcs[i].busy = 1;
 222                         spin_unlock_irqrestore(&cs->lock, flags);
 223                         gig_dbg(DEBUG_CHANNEL, "allocated channel %d", i);
 224                         return cs->bcs + i;
 225                 }
 226         module_put(cs->driver->owner);
 227         spin_unlock_irqrestore(&cs->lock, flags);
 228         gig_dbg(DEBUG_CHANNEL, "no free channel");
 229         return NULL;
 230 }
 231
 232 void gigaset_free_channel(struct bc_state *bcs)
 233 {
 234         unsigned long flags;
 235
 236         spin_lock_irqsave(&bcs->cs->lock, flags);
 237         if (!bcs->busy) {
 238                 gig_dbg(DEBUG_CHANNEL, "could not free channel %d",
 239                         bcs->channel);
 240                 spin_unlock_irqrestore(&bcs->cs->lock, flags);
 241                 return;
 242         }
 243         --bcs->use_count;
 244         bcs->busy = 0;
 245         module_put(bcs->cs->driver->owner);
 246         gig_dbg(DEBUG_CHANNEL, "freed channel %d", bcs->channel);
 247         spin_unlock_irqrestore(&bcs->cs->lock, flags);
 248 }
 249
 250 int gigaset_get_channels(struct cardstate *cs)
 251 {
 252         unsigned long flags;
 253         int i;
 254
 255         spin_lock_irqsave(&cs->lock, flags);
 256         for (i = 0; i < cs->channels; ++i)
 257                 if (cs->bcs[i].use_count) {
 258                         spin_unlock_irqrestore(&cs->lock, flags);
 259                         gig_dbg(DEBUG_CHANNEL,
 260                                 "could not allocate all channels");
 261                         return -EBUSY;
 262                 }
 263         for (i = 0; i < cs->channels; ++i)
 264                 ++cs->bcs[i].use_count;
 265         spin_unlock_irqrestore(&cs->lock, flags);
 266
 267         gig_dbg(DEBUG_CHANNEL, "allocated all channels");
 268
 269         return 0;
 270 }
 271
 272 void gigaset_free_channels(struct cardstate *cs)
 273 {
 274         unsigned long flags;
 275         int i;
 276
 277         gig_dbg(DEBUG_CHANNEL, "unblocking all channels");
 278         spin_lock_irqsave(&cs->lock, flags);
 279         for (i = 0; i < cs->channels; ++i)
 280                 --cs->bcs[i].use_count;
 281         spin_unlock_irqrestore(&cs->lock, flags);
 282 }
 283
 284 void gigaset_block_channels(struct cardstate *cs)
 285 {
 286         unsigned long flags;
 287         int i;
 288
 289         gig_dbg(DEBUG_CHANNEL, "blocking all channels");
 290         spin_lock_irqsave(&cs->lock, flags);
 291         for (i = 0; i < cs->channels; ++i)
 292                 ++cs->bcs[i].use_count;
 293         spin_unlock_irqrestore(&cs->lock, flags);
 294 }
 295
 296 static void clear_events(struct cardstate *cs)
 297 {
 298         struct event_t *ev;
 299         unsigned head, tail;
 300         unsigned long flags;
 301
 302         spin_lock_irqsave(&cs->ev_lock, flags);
 303
 304         head = cs->ev_head;
 305         tail = cs->ev_tail;
 306
 307         while (tail != head) {
 308                 ev = cs->events + head;
 309                 kfree(ev->ptr);
 310                 head = (head + 1) % MAX_EVENTS;
 311         }
 312
 313         cs->ev_head = tail;
 314
 315         spin_unlock_irqrestore(&cs->ev_lock, flags);
 316 }
 317
 318 /**
 319  * gigaset_add_event() - add event to device event queue
 320  * @cs:         device descriptor structure.
 321  * @at_state:   connection state structure.
 322  * @type:       event type.
 323  * @ptr:        pointer parameter for event.
 324  * @parameter:  integer parameter for event.
 325  * @arg:        pointer parameter for event.
 326  *
 327  * Allocate an event queue entry from the device's event queue, and set it up
 328  * with the parameters given.
 329  *
 330  * Return value: added event
 331  */
 332 struct event_t *gigaset_add_event(struct cardstate *cs,
 333                                   struct at_state_t *at_state, int type,
 334                                   void *ptr, int parameter, void *arg)
 335 {
 336         unsigned long flags;
 337         unsigned next, tail;
 338         struct event_t *event = NULL;
 339
 340         gig_dbg(DEBUG_EVENT, "queueing event %d", type);
 341
 342         spin_lock_irqsave(&cs->ev_lock, flags);
 343
 344         tail = cs->ev_tail;
 345         next = (tail + 1) % MAX_EVENTS;
 346         if (unlikely(next == cs->ev_head))
 347                 dev_err(cs->dev, "event queue full\n");
 348         else {
 349                 event = cs->events + tail;
 350                 event->type = type;
 351                 event->at_state = at_state;
 352                 event->cid = -1;
 353                 event->ptr = ptr;
 354                 event->arg = arg;
 355                 event->parameter = parameter;
 356                 cs->ev_tail = next;
 357         }
 358
 359         spin_unlock_irqrestore(&cs->ev_lock, flags);
 360
 361         return event;
 362 }
 363 EXPORT_SYMBOL_GPL(gigaset_add_event);
 364
 365 static void clear_at_state(struct at_state_t *at_state)
 366 {
 367         int i;
 368
 369         for (i = 0; i < STR_NUM; ++i) {
 370                 kfree(at_state->str_var[i]);
 371                 at_state->str_var[i] = NULL;
 372         }
 373 }
 374
 375 static void dealloc_temp_at_states(struct cardstate *cs)
 376 {
 377         struct at_state_t *cur, *next;
 378
 379         list_for_each_entry_safe(cur, next, &cs->temp_at_states, list) {
 380                 list_del(&cur->list);
 381                 clear_at_state(cur);
 382                 kfree(cur);
 383         }
 384 }
 385
 386 static void gigaset_freebcs(struct bc_state *bcs)
 387 {
 388         int i;
 389
 390         gig_dbg(DEBUG_INIT, "freeing bcs[%d]->hw", bcs->channel);
 391         bcs->cs->ops->freebcshw(bcs);
 392
 393         gig_dbg(DEBUG_INIT, "clearing bcs[%d]->at_state", bcs->channel);
 394         clear_at_state(&bcs->at_state);
 395         gig_dbg(DEBUG_INIT, "freeing bcs[%d]->skb", bcs->channel);
 396         dev_kfree_skb(bcs->rx_skb);
 397         bcs->rx_skb = NULL;
 398
 399         for (i = 0; i < AT_NUM; ++i) {
 400                 kfree(bcs->commands[i]);
 401                 bcs->commands[i] = NULL;
 402         }
 403 }
 404
 405 static struct cardstate *alloc_cs(struct gigaset_driver *drv)
 406 {
 407         unsigned long flags;
 408         unsigned i;
 409         struct cardstate *cs;
 410         struct cardstate *ret = NULL;
 411
 412         spin_lock_irqsave(&drv->lock, flags);
 413         if (drv->blocked)
 414                 goto exit;
 415         for (i = 0; i < drv->minors; ++i) {
 416                 cs = drv->cs + i;
 417                 if (!(cs->flags & VALID_MINOR)) {
 418                         cs->flags = VALID_MINOR;
 419                         ret = cs;
 420                         break;
 421                 }
 422         }
 423 exit:
 424         spin_unlock_irqrestore(&drv->lock, flags);
 425         return ret;
 426 }
 427
 428 static void free_cs(struct cardstate *cs)
 429 {
 430         cs->flags = 0;
 431 }
 432
 433 static void make_valid(struct cardstate *cs, unsigned mask)
 434 {
 435         unsigned long flags;
 436         struct gigaset_driver *drv = cs->driver;
 437         spin_lock_irqsave(&drv->lock, flags);
 438         cs->flags |= mask;
 439         spin_unlock_irqrestore(&drv->lock, flags);
 440 }
 441
 442 static void make_invalid(struct cardstate *cs, unsigned mask)
 443 {
 444         unsigned long flags;
 445         struct gigaset_driver *drv = cs->driver;
 446         spin_lock_irqsave(&drv->lock, flags);
 447         cs->flags &= ~mask;
 448         spin_unlock_irqrestore(&drv->lock, flags);
 449 }
 450
 451 /**
 452  * gigaset_freecs() - free all associated ressources of a device
 453  * @cs:         device descriptor structure.
 454  *
 455  * Stops all tasklets and timers, unregisters the device from all
 456  * subsystems it was registered to, deallocates the device structure
 457  * @cs and all structures referenced from it.
 458  * Operations on the device should be stopped before calling this.
 459  */
 460 void gigaset_freecs(struct cardstate *cs)
 461 {
 462         int i;
 463         unsigned long flags;
 464
 465         if (!cs)
 466                 return;
 467
 468         mutex_lock(&cs->mutex);
 469
 470         spin_lock_irqsave(&cs->lock, flags);
 471         cs->running = 0;
 472         spin_unlock_irqrestore(&cs->lock, flags); /* event handler and timer are
 473                                                      not rescheduled below */
 474
 475         tasklet_kill(&cs->event_tasklet);
 476         del_timer_sync(&cs->timer);
 477
 478         switch (cs->cs_init) {
 479         default:
 480                 /* clear B channel structures */
 481                 for (i = 0; i < cs->channels; ++i) {
 482                         gig_dbg(DEBUG_INIT, "clearing bcs[%d]", i);
 483                         gigaset_freebcs(cs->bcs + i);
 484                 }
 485
 486                 /* clear device sysfs */
 487                 gigaset_free_dev_sysfs(cs);
 488
 489                 gigaset_if_free(cs);
 490
 491                 gig_dbg(DEBUG_INIT, "clearing hw");
 492                 cs->ops->freecshw(cs);
 493
 494                 /* fall through */
 495         case 2: /* error in initcshw */
 496                 /* Deregister from LL */
 497                 make_invalid(cs, VALID_ID);
 498                 gigaset_isdn_unregdev(cs);
 499
 500                 /* fall through */
 501         case 1: /* error when registering to LL */
 502                 gig_dbg(DEBUG_INIT, "clearing at_state");
 503                 clear_at_state(&cs->at_state);
 504                 dealloc_temp_at_states(cs);
 505                 clear_events(cs);
 506                 tty_port_destroy(&cs->port);
 507
 508                 /* fall through */
 509         case 0: /* error in basic setup */
 510                 gig_dbg(DEBUG_INIT, "freeing inbuf");
 511                 kfree(cs->inbuf);
 512                 kfree(cs->bcs);
 513         }
 514
 515         mutex_unlock(&cs->mutex);
 516         free_cs(cs);
 517 }
 518 EXPORT_SYMBOL_GPL(gigaset_freecs);
 519
 520 void gigaset_at_init(struct at_state_t *at_state, struct bc_state *bcs,
 521                      struct cardstate *cs, int cid)
 522 {
 523         int i;
 524
 525         INIT_LIST_HEAD(&at_state->list);
 526         at_state->waiting = 0;
 527         at_state->getstring = 0;
 528         at_state->pending_commands = 0;
 529         at_state->timer_expires = 0;
 530         at_state->timer_active = 0;
 531         at_state->timer_index = 0;
 532         at_state->seq_index = 0;
 533         at_state->ConState = 0;
 534         for (i = 0; i < STR_NUM; ++i)
 535                 at_state->str_var[i] = NULL;
 536         at_state->int_var[VAR_ZDLE] = 0;
 537         at_state->int_var[VAR_ZCTP] = -1;
 538         at_state->int_var[VAR_ZSAU] = ZSAU_NULL;
 539         at_state->cs = cs;
 540         at_state->bcs = bcs;
 541         at_state->cid = cid;
 542         if (!cid)
 543                 at_state->replystruct = cs->tabnocid;
 544         else
 545                 at_state->replystruct = cs->tabcid;
 546 }
 547
 548
 549 static void gigaset_inbuf_init(struct inbuf_t *inbuf, struct cardstate *cs)
 550 /* inbuf->read must be allocated before! */
 551 {
 552         inbuf->head = 0;
 553         inbuf->tail = 0;
 554         inbuf->cs = cs;
 555         inbuf->inputstate = INS_command;
 556 }
 557
 558 /**
 559  * gigaset_fill_inbuf() - append received data to input buffer
 560  * @inbuf:      buffer structure.
 561  * @src:        received data.
 562  * @numbytes:   number of bytes received.
 563  *
 564  * Return value: !=0 if some data was appended
 565  */
 566 int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 567                        unsigned numbytes)
 568 {
 569         unsigned n, head, tail, bytesleft;
 570
 571         gig_dbg(DEBUG_INTR, "received %u bytes", numbytes);
 572
 573         if (!numbytes)
 574                 return 0;
 575
 576         bytesleft = numbytes;
 577         tail = inbuf->tail;
 578         head = inbuf->head;
 579         gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
 580
 581         while (bytesleft) {
 582                 if (head > tail)
 583                         n = head - 1 - tail;
 584                 else if (head == 0)
 585                         n = (RBUFSIZE - 1) - tail;
 586                 else
 587                         n = RBUFSIZE - tail;
 588                 if (!n) {
 589                         dev_err(inbuf->cs->dev,
 590                                 "buffer overflow (%u bytes lost)\n",
 591                                 bytesleft);
 592                         break;
 593                 }
 594                 if (n > bytesleft)
 595                         n = bytesleft;
 596                 memcpy(inbuf->data + tail, src, n);
 597                 bytesleft -= n;
 598                 tail = (tail + n) % RBUFSIZE;
 599                 src += n;
 600         }
 601         gig_dbg(DEBUG_INTR, "setting tail to %u", tail);
 602         inbuf->tail = tail;
 603         return numbytes != bytesleft;
 604 }
 605 EXPORT_SYMBOL_GPL(gigaset_fill_inbuf);
 606
 607 /* Initialize the b-channel structure */
 608 static int gigaset_initbcs(struct bc_state *bcs, struct cardstate *cs,
 609                            int channel)
 610 {
 611         int i;
 612
 613         bcs->tx_skb = NULL;
 614
 615         skb_queue_head_init(&bcs->squeue);
 616
 617         bcs->corrupted = 0;
 618         bcs->trans_down = 0;
 619         bcs->trans_up = 0;
 620
 621         gig_dbg(DEBUG_INIT, "setting up bcs[%d]->at_state", channel);
 622         gigaset_at_init(&bcs->at_state, bcs, cs, -1);
 623
 624 #ifdef CONFIG_GIGASET_DEBUG
 625         bcs->emptycount = 0;
 626 #endif
 627
 628         bcs->rx_bufsize = 0;
 629         bcs->rx_skb = NULL;
 630         bcs->rx_fcs = PPP_INITFCS;
 631         bcs->inputstate = 0;
 632         bcs->channel = channel;
 633         bcs->cs = cs;
 634
 635         bcs->chstate = 0;
 636         bcs->use_count = 1;
 637         bcs->busy = 0;
 638         bcs->ignore = cs->ignoreframes;
 639
 640         for (i = 0; i < AT_NUM; ++i)
 641                 bcs->commands[i] = NULL;
 642
 643         spin_lock_init(&bcs->aplock);
 644         bcs->ap = NULL;
 645         bcs->apconnstate = 0;
 646
 647         gig_dbg(DEBUG_INIT, "  setting up bcs[%d]->hw", channel);
 648         return cs->ops->initbcshw(bcs);
 649 }
 650
 651 /**
 652  * gigaset_initcs() - initialize device structure
 653  * @drv:        hardware driver the device belongs to
 654  * @channels:   number of B channels supported by device
 655  * @onechannel: !=0 if B channel data and AT commands share one
 656  *                  communication channel (M10x),
 657  *              ==0 if B channels have separate communication channels (base)
 658  * @ignoreframes:       number of frames to ignore after setting up B channel
 659  * @cidmode:    !=0: start in CallID mode
 660  * @modulename: name of driver module for LL registration
 661  *
 662  * Allocate and initialize cardstate structure for Gigaset driver
 663  * Calls hardware dependent gigaset_initcshw() function
 664  * Calls B channel initialization function gigaset_initbcs() for each B channel
 665  *
 666  * Return value:
 667  *      pointer to cardstate structure
 668  */
 669 struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 670                                  int onechannel, int ignoreframes,
 671                                  int cidmode, const char *modulename)
 672 {
 673         struct cardstate *cs;
 674         unsigned long flags;
 675         int i;
 676
 677         gig_dbg(DEBUG_INIT, "allocating cs");
 678         cs = alloc_cs(drv);
 679         if (!cs) {
 680                 pr_err("maximum number of devices exceeded\n");
 681                 return NULL;
 682         }
 683
 684         cs->cs_init = 0;
 685         cs->channels = channels;
 686         cs->onechannel = onechannel;
 687         cs->ignoreframes = ignoreframes;
 688         INIT_LIST_HEAD(&cs->temp_at_states);
 689         cs->running = 0;
 690         init_timer(&cs->timer); /* clear next & prev */
 691         spin_lock_init(&cs->ev_lock);
 692         cs->ev_tail = 0;
 693         cs->ev_head = 0;
 694
 695         tasklet_init(&cs->event_tasklet, gigaset_handle_event,
 696                      (unsigned long) cs);
 697         tty_port_init(&cs->port);
 698         cs->commands_pending = 0;
 699         cs->cur_at_seq = 0;
 700         cs->gotfwver = -1;
 701         cs->dev = NULL;
 702         cs->tty_dev = NULL;
 703         cs->cidmode = cidmode != 0;
 704         cs->tabnocid = gigaset_tab_nocid;
 705         cs->tabcid = gigaset_tab_cid;
 706
 707         init_waitqueue_head(&cs->waitqueue);
 708         cs->waiting = 0;
 709
 710         cs->mode = M_UNKNOWN;
 711         cs->mstate = MS_UNINITIALIZED;
 712
 713         cs->bcs = kmalloc(channels * sizeof(struct bc_state), GFP_KERNEL);
 714         cs->inbuf = kmalloc(sizeof(struct inbuf_t), GFP_KERNEL);
 715         if (!cs->bcs || !cs->inbuf) {
 716                 pr_err("out of memory\n");
 717                 goto error;
 718         }
 719         ++cs->cs_init;
 720
 721         gig_dbg(DEBUG_INIT, "setting up at_state");
 722         spin_lock_init(&cs->lock);
 723         gigaset_at_init(&cs->at_state, NULL, cs, 0);
 724         cs->dle = 0;
 725         cs->cbytes = 0;
 726
 727         gig_dbg(DEBUG_INIT, "setting up inbuf");
 728         gigaset_inbuf_init(cs->inbuf, cs);
 729
 730         cs->connected = 0;
 731         cs->isdn_up = 0;
 732
 733         gig_dbg(DEBUG_INIT, "setting up cmdbuf");
 734         cs->cmdbuf = cs->lastcmdbuf = NULL;
 735         spin_lock_init(&cs->cmdlock);
 736         cs->curlen = 0;
 737         cs->cmdbytes = 0;
 738
 739         gig_dbg(DEBUG_INIT, "setting up iif");
 740         if (gigaset_isdn_regdev(cs, modulename) < 0) {
 741                 pr_err("error registering ISDN device\n");
 742                 goto error;
 743         }
 744
 745         make_valid(cs, VALID_ID);
 746         ++cs->cs_init;
 747         gig_dbg(DEBUG_INIT, "setting up hw");
 748         if (cs->ops->initcshw(cs) < 0)
 749                 goto error;
 750
 751         ++cs->cs_init;
 752
 753         /* set up character device */
 754         gigaset_if_init(cs);
 755
 756         /* set up device sysfs */
 757         gigaset_init_dev_sysfs(cs);
 758
 759         /* set up channel data structures */
 760         for (i = 0; i < channels; ++i) {
 761                 gig_dbg(DEBUG_INIT, "setting up bcs[%d]", i);
 762                 if (gigaset_initbcs(cs->bcs + i, cs, i) < 0) {
 763                         pr_err("could not allocate channel %d data\n", i);
 764                         goto error;
 765                 }
 766         }
 767
 768         spin_lock_irqsave(&cs->lock, flags);
 769         cs->running = 1;
 770         spin_unlock_irqrestore(&cs->lock, flags);
 771         setup_timer(&cs->timer, timer_tick, (unsigned long) cs);
 772         cs->timer.expires = jiffies + msecs_to_jiffies(GIG_TICK);
 773         add_timer(&cs->timer);
 774
 775         gig_dbg(DEBUG_INIT, "cs initialized");
 776         return cs;
 777
 778 error:
 779         gig_dbg(DEBUG_INIT, "failed");
 780         gigaset_freecs(cs);
 781         return NULL;
 782 }
 783 EXPORT_SYMBOL_GPL(gigaset_initcs);
 784
 785 /* ReInitialize the b-channel structure on hangup */
 786 void gigaset_bcs_reinit(struct bc_state *bcs)
 787 {
 788         struct sk_buff *skb;
 789         struct cardstate *cs = bcs->cs;
 790         unsigned long flags;
 791
 792         while ((skb = skb_dequeue(&bcs->squeue)) != NULL)
 793                 dev_kfree_skb(skb);
 794
 795         spin_lock_irqsave(&cs->lock, flags);
 796         clear_at_state(&bcs->at_state);
 797         bcs->at_state.ConState = 0;
 798         bcs->at_state.timer_active = 0;
 799         bcs->at_state.timer_expires = 0;
 800         bcs->at_state.cid = -1;                 /* No CID defined */
 801         spin_unlock_irqrestore(&cs->lock, flags);
 802
 803         bcs->inputstate = 0;
 804
 805 #ifdef CONFIG_GIGASET_DEBUG
 806         bcs->emptycount = 0;
 807 #endif
 808
 809         bcs->rx_fcs = PPP_INITFCS;
 810         bcs->chstate = 0;
 811
 812         bcs->ignore = cs->ignoreframes;
 813         dev_kfree_skb(bcs->rx_skb);
 814         bcs->rx_skb = NULL;
 815
 816         cs->ops->reinitbcshw(bcs);
 817 }
 818
 819 static void cleanup_cs(struct cardstate *cs)
 820 {
 821         struct cmdbuf_t *cb, *tcb;
 822         int i;
 823         unsigned long flags;
 824
 825         spin_lock_irqsave(&cs->lock, flags);
 826
 827         cs->mode = M_UNKNOWN;
 828         cs->mstate = MS_UNINITIALIZED;
 829
 830         clear_at_state(&cs->at_state);
 831         dealloc_temp_at_states(cs);
 832         gigaset_at_init(&cs->at_state, NULL, cs, 0);
 833
 834         cs->inbuf->inputstate = INS_command;
 835         cs->inbuf->head = 0;
 836         cs->inbuf->tail = 0;
 837
 838         cb = cs->cmdbuf;
 839         while (cb) {
 840                 tcb = cb;
 841                 cb = cb->next;
 842                 kfree(tcb);
 843         }
 844         cs->cmdbuf = cs->lastcmdbuf = NULL;
 845         cs->curlen = 0;
 846         cs->cmdbytes = 0;
 847         cs->gotfwver = -1;
 848         cs->dle = 0;
 849         cs->cur_at_seq = 0;
 850         cs->commands_pending = 0;
 851         cs->cbytes = 0;
 852
 853         spin_unlock_irqrestore(&cs->lock, flags);
 854
 855         for (i = 0; i < cs->channels; ++i) {
 856                 gigaset_freebcs(cs->bcs + i);
 857                 if (gigaset_initbcs(cs->bcs + i, cs, i) < 0)
 858                         pr_err("could not allocate channel %d data\n", i);
 859         }
 860
 861         if (cs->waiting) {
 862                 cs->cmd_result = -ENODEV;
 863                 cs->waiting = 0;
 864                 wake_up_interruptible(&cs->waitqueue);
 865         }
 866 }
 867
 868
 869 /**
 870  * gigaset_start() - start device operations
 871  * @cs:         device descriptor structure.
 872  *
 873  * Prepares the device for use by setting up communication parameters,
 874  * scheduling an EV_START event to initiate device initialization, and
 875  * waiting for completion of the initialization.
 876  *
 877  * Return value:
 878  *      0 on success, error code < 0 on failure
 879  */
 880 int gigaset_start(struct cardstate *cs)
 881 {
 882         unsigned long flags;
 883
 884         if (mutex_lock_interruptible(&cs->mutex))
 885                 return -EBUSY;
 886
 887         spin_lock_irqsave(&cs->lock, flags);
 888         cs->connected = 1;
 889         spin_unlock_irqrestore(&cs->lock, flags);
 890
 891         if (cs->mstate != MS_LOCKED) {
 892                 cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR | TIOCM_RTS);
 893                 cs->ops->baud_rate(cs, B115200);
 894                 cs->ops->set_line_ctrl(cs, CS8);
 895                 cs->control_state = TIOCM_DTR | TIOCM_RTS;
 896         }
 897
 898         cs->waiting = 1;
 899
 900         if (!gigaset_add_event(cs, &cs->at_state, EV_START, NULL, 0, NULL)) {
 901                 cs->waiting = 0;
 902                 goto error;
 903         }
 904         gigaset_schedule_event(cs);
 905
 906         wait_event(cs->waitqueue, !cs->waiting);
 907
 908         mutex_unlock(&cs->mutex);
 909         return 0;
 910
 911 error:
 912         mutex_unlock(&cs->mutex);
 913         return -ENOMEM;
 914 }
 915 EXPORT_SYMBOL_GPL(gigaset_start);
 916
 917 /**
 918  * gigaset_shutdown() - shut down device operations
 919  * @cs:         device descriptor structure.
 920  *
 921  * Deactivates the device by scheduling an EV_SHUTDOWN event and
 922  * waiting for completion of the shutdown.
 923  *
 924  * Return value:
 925  *      0 - success, -ENODEV - error (no device associated)
 926  */
 927 int gigaset_shutdown(struct cardstate *cs)
 928 {
 929         mutex_lock(&cs->mutex);
 930
 931         if (!(cs->flags & VALID_MINOR)) {
 932                 mutex_unlock(&cs->mutex);
 933                 return -ENODEV;
 934         }
 935
 936         cs->waiting = 1;
 937
 938         if (!gigaset_add_event(cs, &cs->at_state, EV_SHUTDOWN, NULL, 0, NULL))
 939                 goto exit;
 940         gigaset_schedule_event(cs);
 941
 942         wait_event(cs->waitqueue, !cs->waiting);
 943
 944         cleanup_cs(cs);
 945
 946 exit:
 947         mutex_unlock(&cs->mutex);
 948         return 0;
 949 }
 950 EXPORT_SYMBOL_GPL(gigaset_shutdown);
 951
 952 /**
 953  * gigaset_stop() - stop device operations
 954  * @cs:         device descriptor structure.
 955  *
 956  * Stops operations on the device by scheduling an EV_STOP event and
 957  * waiting for completion of the shutdown.
 958  */
 959 void gigaset_stop(struct cardstate *cs)
 960 {
 961         mutex_lock(&cs->mutex);
 962
 963         cs->waiting = 1;
 964
 965         if (!gigaset_add_event(cs, &cs->at_state, EV_STOP, NULL, 0, NULL))
 966                 goto exit;
 967         gigaset_schedule_event(cs);
 968
 969         wait_event(cs->waitqueue, !cs->waiting);
 970
 971         cleanup_cs(cs);
 972
 973 exit:
 974         mutex_unlock(&cs->mutex);
 975 }
 976 EXPORT_SYMBOL_GPL(gigaset_stop);
 977
 978 static LIST_HEAD(drivers);
 979 static DEFINE_SPINLOCK(driver_lock);
 980
 981 struct cardstate *gigaset_get_cs_by_id(int id)
 982 {
 983         unsigned long flags;
 984         struct cardstate *ret = NULL;
 985         struct cardstate *cs;
 986         struct gigaset_driver *drv;
 987         unsigned i;
 988
 989         spin_lock_irqsave(&driver_lock, flags);
 990         list_for_each_entry(drv, &drivers, list) {
 991                 spin_lock(&drv->lock);
 992                 for (i = 0; i < drv->minors; ++i) {
 993                         cs = drv->cs + i;
 994                         if ((cs->flags & VALID_ID) && cs->myid == id) {
 995                                 ret = cs;
 996                                 break;
 997                         }
 998                 }
 999                 spin_unlock(&drv->lock);
1000                 if (ret)
1001                         break;
1002         }
1003         spin_unlock_irqrestore(&driver_lock, flags);
1004         return ret;
1005 }
1006
1007 static struct cardstate *gigaset_get_cs_by_minor(unsigned minor)
1008 {
1009         unsigned long flags;
1010         struct cardstate *ret = NULL;
1011         struct gigaset_driver *drv;
1012         unsigned index;
1013
1014         spin_lock_irqsave(&driver_lock, flags);
1015         list_for_each_entry(drv, &drivers, list) {
1016                 if (minor < drv->minor || minor >= drv->minor + drv->minors)
1017                         continue;
1018                 index = minor - drv->minor;
1019                 spin_lock(&drv->lock);
1020                 if (drv->cs[index].flags & VALID_MINOR)
1021                         ret = drv->cs + index;
1022                 spin_unlock(&drv->lock);
1023                 if (ret)
1024                         break;
1025         }
1026         spin_unlock_irqrestore(&driver_lock, flags);
1027         return ret;
1028 }
1029
1030 struct cardstate *gigaset_get_cs_by_tty(struct tty_struct *tty)
1031 {
1032         return gigaset_get_cs_by_minor(tty->index + tty->driver->minor_start);
1033 }
1034
1035 /**
1036  * gigaset_freedriver() - free all associated ressources of a driver
1037  * @drv:        driver descriptor structure.
1038  *
1039  * Unregisters the driver from the system and deallocates the driver
1040  * structure @drv and all structures referenced from it.
1041  * All devices should be shut down before calling this.
1042  */
1043 void gigaset_freedriver(struct gigaset_driver *drv)
1044 {
1045         unsigned long flags;
1046
1047         spin_lock_irqsave(&driver_lock, flags);
1048         list_del(&drv->list);
1049         spin_unlock_irqrestore(&driver_lock, flags);
1050
1051         gigaset_if_freedriver(drv);
1052
1053         kfree(drv->cs);
1054         kfree(drv);
1055 }
1056 EXPORT_SYMBOL_GPL(gigaset_freedriver);
1057
1058 /**
1059  * gigaset_initdriver() - initialize driver structure
1060  * @minor:      First minor number
1061  * @minors:     Number of minors this driver can handle
1062  * @procname:   Name of the driver
1063  * @devname:    Name of the device files (prefix without minor number)
1064  *
1065  * Allocate and initialize gigaset_driver structure. Initialize interface.
1066  *
1067  * Return value:
1068  *      Pointer to the gigaset_driver structure on success, NULL on failure.
1069  */
1070 struct gigaset_driver *gigaset_initdriver(unsigned minor, unsigned minors,
1071                                           const char *procname,
1072                                           const char *devname,
1073                                           const struct gigaset_ops *ops,
1074                                           struct module *owner)
1075 {
1076         struct gigaset_driver *drv;
1077         unsigned long flags;
1078         unsigned i;
1079
1080         drv = kmalloc(sizeof *drv, GFP_KERNEL);
1081         if (!drv)
1082                 return NULL;
1083
1084         drv->have_tty = 0;
1085         drv->minor = minor;
1086         drv->minors = minors;
1087         spin_lock_init(&drv->lock);
1088         drv->blocked = 0;
1089         drv->ops = ops;
1090         drv->owner = owner;
1091         INIT_LIST_HEAD(&drv->list);
1092
1093         drv->cs = kmalloc(minors * sizeof *drv->cs, GFP_KERNEL);
1094         if (!drv->cs)
1095                 goto error;
1096
1097         for (i = 0; i < minors; ++i) {
1098                 drv->cs[i].flags = 0;
1099                 drv->cs[i].driver = drv;
1100                 drv->cs[i].ops = drv->ops;
1101                 drv->cs[i].minor_index = i;
1102                 mutex_init(&drv->cs[i].mutex);
1103         }
1104
1105         gigaset_if_initdriver(drv, procname, devname);
1106
1107         spin_lock_irqsave(&driver_lock, flags);
1108         list_add(&drv->list, &drivers);
1109         spin_unlock_irqrestore(&driver_lock, flags);
1110
1111         return drv;
1112
1113 error:
1114         kfree(drv);
1115         return NULL;
1116 }
1117 EXPORT_SYMBOL_GPL(gigaset_initdriver);
1118
1119 /**
1120  * gigaset_blockdriver() - block driver
1121  * @drv:        driver descriptor structure.
1122  *
1123  * Prevents the driver from attaching new devices, in preparation for
1124  * deregistration.
1125  */
1126 void gigaset_blockdriver(struct gigaset_driver *drv)
1127 {
1128         drv->blocked = 1;
1129 }
1130 EXPORT_SYMBOL_GPL(gigaset_blockdriver);
1131
1132 static int __init gigaset_init_module(void)
1133 {
1134         /* in accordance with the principle of least astonishment,
1135          * setting the 'debug' parameter to 1 activates a sensible
1136          * set of default debug levels
1137          */
1138         if (gigaset_debuglevel == 1)
1139                 gigaset_debuglevel = DEBUG_DEFAULT;
1140
1141         pr_info(DRIVER_DESC DRIVER_DESC_DEBUG "\n");
1142         gigaset_isdn_regdrv();
1143         return 0;
1144 }
1145
1146 static void __exit gigaset_exit_module(void)
1147 {
1148         gigaset_isdn_unregdrv();
1149 }
1150
1151 module_init(gigaset_init_module);
1152 module_exit(gigaset_exit_module);
1153
1154 MODULE_AUTHOR(DRIVER_AUTHOR);
1155 MODULE_DESCRIPTION(DRIVER_DESC);
1156
1157 MODULE_LICENSE("GPL");