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/ctype.h>
  18 #include <linux/module.h>
  19 #include <linux/moduleparam.h>
  20
  21 /* Version Information */
  22 #define DRIVER_AUTHOR "Hansjoerg Lipp <hjlipp@web.de>, Tilman Schmidt <tilman@imap.cc>, Stefan Eilers"
  23 #define DRIVER_DESC "Driver for Gigaset 307x"
  24
  25 #ifdef CONFIG_GIGASET_DEBUG
  26 #define DRIVER_DESC_DEBUG " (debug build)"
  27 #else
  28 #define DRIVER_DESC_DEBUG ""
  29 #endif
  30
  31 /* Module parameters */
  32 int gigaset_debuglevel = DEBUG_DEFAULT;
  33 EXPORT_SYMBOL_GPL(gigaset_debuglevel);
  34 module_param_named(debug, gigaset_debuglevel, int, S_IRUGO|S_IWUSR);
  35 MODULE_PARM_DESC(debug, "debug level");
  36
  37 /* driver state flags */
  38 #define VALID_MINOR     0x01
  39 #define VALID_ID        0x02
  40
  41 /**
  42  * gigaset_dbg_buffer() - dump data in ASCII and hex for debugging
  43  * @level:      debugging level.
  44  * @msg:        message prefix.
  45  * @len:        number of bytes to dump.
  46  * @buf:        data to dump.
  47  *
  48  * If the current debugging level includes one of the bits set in @level,
  49  * @len bytes starting at @buf are logged to dmesg at KERN_DEBUG prio,
  50  * prefixed by the text @msg.
  51  */
  52 void gigaset_dbg_buffer(enum debuglevel level, const unsigned char *msg,
  53                         size_t len, const unsigned char *buf)
  54 {
  55         unsigned char outbuf[80];
  56         unsigned char c;
  57         size_t space = sizeof outbuf - 1;
  58         unsigned char *out = outbuf;
  59         size_t numin = len;
  60
  61         while (numin--) {
  62                 c = *buf++;
  63                 if (c == '~' || c == '^' || c == '\\') {
  64                         if (!space--)
  65                                 break;
  66                         *out++ = '\\';
  67                 }
  68                 if (c & 0x80) {
  69                         if (!space--)
  70                                 break;
  71                         *out++ = '~';
  72                         c ^= 0x80;
  73                 }
  74                 if (c < 0x20 || c == 0x7f) {
  75                         if (!space--)
  76                                 break;
  77                         *out++ = '^';
  78                         c ^= 0x40;
  79                 }
  80                 if (!space--)
  81                         break;
  82                 *out++ = c;
  83         }
  84         *out = 0;
  85
  86         gig_dbg(level, "%s (%u bytes): %s", msg, (unsigned) len, outbuf);
  87 }
  88 EXPORT_SYMBOL_GPL(gigaset_dbg_buffer);
  89
  90 static int setflags(struct cardstate *cs, unsigned flags, unsigned delay)
  91 {
  92         int r;
  93
  94         r = cs->ops->set_modem_ctrl(cs, cs->control_state, flags);
  95         cs->control_state = flags;
  96         if (r < 0)
  97                 return r;
  98
  99         if (delay) {
 100                 set_current_state(TASK_INTERRUPTIBLE);
 101                 schedule_timeout(delay * HZ / 1000);
 102         }
 103
 104         return 0;
 105 }
 106
 107 int gigaset_enterconfigmode(struct cardstate *cs)
 108 {
 109         int i, r;
 110
 111         cs->control_state = TIOCM_RTS; //FIXME
 112
 113         r = setflags(cs, TIOCM_DTR, 200);
 114         if (r < 0)
 115                 goto error;
 116         r = setflags(cs, 0, 200);
 117         if (r < 0)
 118                 goto error;
 119         for (i = 0; i < 5; ++i) {
 120                 r = setflags(cs, TIOCM_RTS, 100);
 121                 if (r < 0)
 122                         goto error;
 123                 r = setflags(cs, 0, 100);
 124                 if (r < 0)
 125                         goto error;
 126         }
 127         r = setflags(cs, TIOCM_RTS|TIOCM_DTR, 800);
 128         if (r < 0)
 129                 goto error;
 130
 131         return 0;
 132
 133 error:
 134         dev_err(cs->dev, "error %d on setuartbits\n", -r);
 135         cs->control_state = TIOCM_RTS|TIOCM_DTR; // FIXME is this a good value?
 136         cs->ops->set_modem_ctrl(cs, 0, TIOCM_RTS|TIOCM_DTR);
 137
 138         return -1; //r
 139 }
 140
 141 static int test_timeout(struct at_state_t *at_state)
 142 {
 143         if (!at_state->timer_expires)
 144                 return 0;
 145
 146         if (--at_state->timer_expires) {
 147                 gig_dbg(DEBUG_MCMD, "decreased timer of %p to %lu",
 148                         at_state, at_state->timer_expires);
 149                 return 0;
 150         }
 151
 152         if (!gigaset_add_event(at_state->cs, at_state, EV_TIMEOUT, NULL,
 153                                at_state->timer_index, NULL)) {
 154                 //FIXME what should we do?
 155         }
 156
 157         return 1;
 158 }
 159
 160 static void timer_tick(unsigned long data)
 161 {
 162         struct cardstate *cs = (struct cardstate *) data;
 163         unsigned long flags;
 164         unsigned channel;
 165         struct at_state_t *at_state;
 166         int timeout = 0;
 167
 168         spin_lock_irqsave(&cs->lock, flags);
 169
 170         for (channel = 0; channel < cs->channels; ++channel)
 171                 if (test_timeout(&cs->bcs[channel].at_state))
 172                         timeout = 1;
 173
 174         if (test_timeout(&cs->at_state))
 175                 timeout = 1;
 176
 177         list_for_each_entry(at_state, &cs->temp_at_states, list)
 178                 if (test_timeout(at_state))
 179                         timeout = 1;
 180
 181         if (cs->running) {
 182                 mod_timer(&cs->timer, jiffies + msecs_to_jiffies(GIG_TICK));
 183                 if (timeout) {
 184                         gig_dbg(DEBUG_CMD, "scheduling timeout");
 185                         tasklet_schedule(&cs->event_tasklet);
 186                 }
 187         }
 188
 189         spin_unlock_irqrestore(&cs->lock, flags);
 190 }
 191
 192 int gigaset_get_channel(struct bc_state *bcs)
 193 {
 194         unsigned long flags;
 195
 196         spin_lock_irqsave(&bcs->cs->lock, flags);
 197         if (bcs->use_count || !try_module_get(bcs->cs->driver->owner)) {
 198                 gig_dbg(DEBUG_ANY, "could not allocate channel %d",
 199                         bcs->channel);
 200                 spin_unlock_irqrestore(&bcs->cs->lock, flags);
 201                 return 0;
 202         }
 203         ++bcs->use_count;
 204         bcs->busy = 1;
 205         gig_dbg(DEBUG_ANY, "allocated channel %d", bcs->channel);
 206         spin_unlock_irqrestore(&bcs->cs->lock, flags);
 207         return 1;
 208 }
 209
 210 struct bc_state *gigaset_get_free_channel(struct cardstate *cs)
 211 {
 212         unsigned long flags;
 213         int i;
 214
 215         spin_lock_irqsave(&cs->lock, flags);
 216         if (!try_module_get(cs->driver->owner)) {
 217                 gig_dbg(DEBUG_ANY,
 218                         "could not get module for allocating channel");
 219                 spin_unlock_irqrestore(&cs->lock, flags);
 220                 return NULL;
 221         }
 222         for (i = 0; i < cs->channels; ++i)
 223                 if (!cs->bcs[i].use_count) {
 224                         ++cs->bcs[i].use_count;
 225                         cs->bcs[i].busy = 1;
 226                         spin_unlock_irqrestore(&cs->lock, flags);
 227                         gig_dbg(DEBUG_ANY, "allocated channel %d", i);
 228                         return cs->bcs + i;
 229                 }
 230         module_put(cs->driver->owner);
 231         spin_unlock_irqrestore(&cs->lock, flags);
 232         gig_dbg(DEBUG_ANY, "no free channel");
 233         return NULL;
 234 }
 235
 236 void gigaset_free_channel(struct bc_state *bcs)
 237 {
 238         unsigned long flags;
 239
 240         spin_lock_irqsave(&bcs->cs->lock, flags);
 241         if (!bcs->busy) {
 242                 gig_dbg(DEBUG_ANY, "could not free channel %d", bcs->channel);
 243                 spin_unlock_irqrestore(&bcs->cs->lock, flags);
 244                 return;
 245         }
 246         --bcs->use_count;
 247         bcs->busy = 0;
 248         module_put(bcs->cs->driver->owner);
 249         gig_dbg(DEBUG_ANY, "freed channel %d", bcs->channel);
 250         spin_unlock_irqrestore(&bcs->cs->lock, flags);
 251 }
 252
 253 int gigaset_get_channels(struct cardstate *cs)
 254 {
 255         unsigned long flags;
 256         int i;
 257
 258         spin_lock_irqsave(&cs->lock, flags);
 259         for (i = 0; i < cs->channels; ++i)
 260                 if (cs->bcs[i].use_count) {
 261                         spin_unlock_irqrestore(&cs->lock, flags);
 262                         gig_dbg(DEBUG_ANY, "could not allocate all channels");
 263                         return 0;
 264                 }
 265         for (i = 0; i < cs->channels; ++i)
 266                 ++cs->bcs[i].use_count;
 267         spin_unlock_irqrestore(&cs->lock, flags);
 268
 269         gig_dbg(DEBUG_ANY, "allocated all channels");
 270
 271         return 1;
 272 }
 273
 274 void gigaset_free_channels(struct cardstate *cs)
 275 {
 276         unsigned long flags;
 277         int i;
 278
 279         gig_dbg(DEBUG_ANY, "unblocking all channels");
 280         spin_lock_irqsave(&cs->lock, flags);
 281         for (i = 0; i < cs->channels; ++i)
 282                 --cs->bcs[i].use_count;
 283         spin_unlock_irqrestore(&cs->lock, flags);
 284 }
 285
 286 void gigaset_block_channels(struct cardstate *cs)
 287 {
 288         unsigned long flags;
 289         int i;
 290
 291         gig_dbg(DEBUG_ANY, "blocking all channels");
 292         spin_lock_irqsave(&cs->lock, flags);
 293         for (i = 0; i < cs->channels; ++i)
 294                 ++cs->bcs[i].use_count;
 295         spin_unlock_irqrestore(&cs->lock, flags);
 296 }
 297
 298 static void clear_events(struct cardstate *cs)
 299 {
 300         struct event_t *ev;
 301         unsigned head, tail;
 302         unsigned long flags;
 303
 304         spin_lock_irqsave(&cs->ev_lock, flags);
 305
 306         head = cs->ev_head;
 307         tail = cs->ev_tail;
 308
 309         while (tail != head) {
 310                 ev = cs->events + head;
 311                 kfree(ev->ptr);
 312                 head = (head + 1) % MAX_EVENTS;
 313         }
 314
 315         cs->ev_head = tail;
 316
 317         spin_unlock_irqrestore(&cs->ev_lock, flags);
 318 }
 319
 320 /**
 321  * gigaset_add_event() - add event to device event queue
 322  * @cs:         device descriptor structure.
 323  * @at_state:   connection state structure.
 324  * @type:       event type.
 325  * @ptr:        pointer parameter for event.
 326  * @parameter:  integer parameter for event.
 327  * @arg:        pointer parameter for event.
 328  *
 329  * Allocate an event queue entry from the device's event queue, and set it up
 330  * with the parameters given.
 331  *
 332  * Return value: added event
 333  */
 334 struct event_t *gigaset_add_event(struct cardstate *cs,
 335                                   struct at_state_t *at_state, int type,
 336                                   void *ptr, int parameter, void *arg)
 337 {
 338         unsigned long flags;
 339         unsigned next, tail;
 340         struct event_t *event = NULL;
 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 free_strings(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 clear_at_state(struct at_state_t *at_state)
 376 {
 377         free_strings(at_state);
 378 }
 379
 380 static void dealloc_at_states(struct cardstate *cs)
 381 {
 382         struct at_state_t *cur, *next;
 383
 384         list_for_each_entry_safe(cur, next, &cs->temp_at_states, list) {
 385                 list_del(&cur->list);
 386                 free_strings(cur);
 387                 kfree(cur);
 388         }
 389 }
 390
 391 static void gigaset_freebcs(struct bc_state *bcs)
 392 {
 393         int i;
 394
 395         gig_dbg(DEBUG_INIT, "freeing bcs[%d]->hw", bcs->channel);
 396         if (!bcs->cs->ops->freebcshw(bcs)) {
 397                 gig_dbg(DEBUG_INIT, "failed");
 398         }
 399
 400         gig_dbg(DEBUG_INIT, "clearing bcs[%d]->at_state", bcs->channel);
 401         clear_at_state(&bcs->at_state);
 402         gig_dbg(DEBUG_INIT, "freeing bcs[%d]->skb", bcs->channel);
 403         dev_kfree_skb(bcs->skb);
 404         bcs->skb = NULL;
 405
 406         for (i = 0; i < AT_NUM; ++i) {
 407                 kfree(bcs->commands[i]);
 408                 bcs->commands[i] = NULL;
 409         }
 410 }
 411
 412 static struct cardstate *alloc_cs(struct gigaset_driver *drv)
 413 {
 414         unsigned long flags;
 415         unsigned i;
 416         struct cardstate *cs;
 417         struct cardstate *ret = NULL;
 418
 419         spin_lock_irqsave(&drv->lock, flags);
 420         if (drv->blocked)
 421                 goto exit;
 422         for (i = 0; i < drv->minors; ++i) {
 423                 cs = drv->cs + i;
 424                 if (!(cs->flags & VALID_MINOR)) {
 425                         cs->flags = VALID_MINOR;
 426                         ret = cs;
 427                         break;
 428                 }
 429         }
 430 exit:
 431         spin_unlock_irqrestore(&drv->lock, flags);
 432         return ret;
 433 }
 434
 435 static void free_cs(struct cardstate *cs)
 436 {
 437         cs->flags = 0;
 438 }
 439
 440 static void make_valid(struct cardstate *cs, unsigned mask)
 441 {
 442         unsigned long flags;
 443         struct gigaset_driver *drv = cs->driver;
 444         spin_lock_irqsave(&drv->lock, flags);
 445         cs->flags |= mask;
 446         spin_unlock_irqrestore(&drv->lock, flags);
 447 }
 448
 449 static void make_invalid(struct cardstate *cs, unsigned mask)
 450 {
 451         unsigned long flags;
 452         struct gigaset_driver *drv = cs->driver;
 453         spin_lock_irqsave(&drv->lock, flags);
 454         cs->flags &= ~mask;
 455         spin_unlock_irqrestore(&drv->lock, flags);
 456 }
 457
 458 /**
 459  * gigaset_freecs() - free all associated ressources of a device
 460  * @cs:         device descriptor structure.
 461  *
 462  * Stops all tasklets and timers, unregisters the device from all
 463  * subsystems it was registered to, deallocates the device structure
 464  * @cs and all structures referenced from it.
 465  * Operations on the device should be stopped before calling this.
 466  */
 467 void gigaset_freecs(struct cardstate *cs)
 468 {
 469         int i;
 470         unsigned long flags;
 471
 472         if (!cs)
 473                 return;
 474
 475         mutex_lock(&cs->mutex);
 476
 477         if (!cs->bcs)
 478                 goto f_cs;
 479         if (!cs->inbuf)
 480                 goto f_bcs;
 481
 482         spin_lock_irqsave(&cs->lock, flags);
 483         cs->running = 0;
 484         spin_unlock_irqrestore(&cs->lock, flags); /* event handler and timer are
 485                                                      not rescheduled below */
 486
 487         tasklet_kill(&cs->event_tasklet);
 488         del_timer_sync(&cs->timer);
 489
 490         switch (cs->cs_init) {
 491         default:
 492                 /* clear B channel structures */
 493                 for (i = 0; i < cs->channels; ++i) {
 494                         gig_dbg(DEBUG_INIT, "clearing bcs[%d]", i);
 495                         gigaset_freebcs(cs->bcs + i);
 496                 }
 497
 498                 /* clear device sysfs */
 499                 gigaset_free_dev_sysfs(cs);
 500
 501                 gigaset_if_free(cs);
 502
 503                 gig_dbg(DEBUG_INIT, "clearing hw");
 504                 cs->ops->freecshw(cs);
 505
 506                 //FIXME cmdbuf
 507
 508                 /* fall through */
 509         case 2: /* error in initcshw */
 510                 /* Deregister from LL */
 511                 make_invalid(cs, VALID_ID);
 512                 gigaset_isdn_unregister(cs);
 513
 514                 /* fall through */
 515         case 1: /* error when registering to LL */
 516                 gig_dbg(DEBUG_INIT, "clearing at_state");
 517                 clear_at_state(&cs->at_state);
 518                 dealloc_at_states(cs);
 519
 520                 /* fall through */
 521         case 0: /* error in basic setup */
 522                 clear_events(cs);
 523                 gig_dbg(DEBUG_INIT, "freeing inbuf");
 524                 kfree(cs->inbuf);
 525         }
 526 f_bcs:  gig_dbg(DEBUG_INIT, "freeing bcs[]");
 527         kfree(cs->bcs);
 528 f_cs:   gig_dbg(DEBUG_INIT, "freeing cs");
 529         mutex_unlock(&cs->mutex);
 530         free_cs(cs);
 531 }
 532 EXPORT_SYMBOL_GPL(gigaset_freecs);
 533
 534 void gigaset_at_init(struct at_state_t *at_state, struct bc_state *bcs,
 535                      struct cardstate *cs, int cid)
 536 {
 537         int i;
 538
 539         INIT_LIST_HEAD(&at_state->list);
 540         at_state->waiting = 0;
 541         at_state->getstring = 0;
 542         at_state->pending_commands = 0;
 543         at_state->timer_expires = 0;
 544         at_state->timer_active = 0;
 545         at_state->timer_index = 0;
 546         at_state->seq_index = 0;
 547         at_state->ConState = 0;
 548         for (i = 0; i < STR_NUM; ++i)
 549                 at_state->str_var[i] = NULL;
 550         at_state->int_var[VAR_ZDLE] = 0;
 551         at_state->int_var[VAR_ZCTP] = -1;
 552         at_state->int_var[VAR_ZSAU] = ZSAU_NULL;
 553         at_state->cs = cs;
 554         at_state->bcs = bcs;
 555         at_state->cid = cid;
 556         if (!cid)
 557                 at_state->replystruct = cs->tabnocid;
 558         else
 559                 at_state->replystruct = cs->tabcid;
 560 }
 561
 562
 563 static void gigaset_inbuf_init(struct inbuf_t *inbuf, struct cardstate *cs)
 564 /* inbuf->read must be allocated before! */
 565 {
 566         inbuf->head = 0;
 567         inbuf->tail = 0;
 568         inbuf->cs = cs;
 569         inbuf->inputstate = INS_command;
 570 }
 571
 572 /**
 573  * gigaset_fill_inbuf() - append received data to input buffer
 574  * @inbuf:      buffer structure.
 575  * @src:        received data.
 576  * @numbytes:   number of bytes received.
 577  */
 578 int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 579                        unsigned numbytes)
 580 {
 581         unsigned n, head, tail, bytesleft;
 582
 583         gig_dbg(DEBUG_INTR, "received %u bytes", numbytes);
 584
 585         if (!numbytes)
 586                 return 0;
 587
 588         bytesleft = numbytes;
 589         tail = inbuf->tail;
 590         head = inbuf->head;
 591         gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
 592
 593         while (bytesleft) {
 594                 if (head > tail)
 595                         n = head - 1 - tail;
 596                 else if (head == 0)
 597                         n = (RBUFSIZE-1) - tail;
 598                 else
 599                         n = RBUFSIZE - tail;
 600                 if (!n) {
 601                         dev_err(inbuf->cs->dev,
 602                                 "buffer overflow (%u bytes lost)\n",
 603                                 bytesleft);
 604                         break;
 605                 }
 606                 if (n > bytesleft)
 607                         n = bytesleft;
 608                 memcpy(inbuf->data + tail, src, n);
 609                 bytesleft -= n;
 610                 tail = (tail + n) % RBUFSIZE;
 611                 src += n;
 612         }
 613         gig_dbg(DEBUG_INTR, "setting tail to %u", tail);
 614         inbuf->tail = tail;
 615         return numbytes != bytesleft;
 616 }
 617 EXPORT_SYMBOL_GPL(gigaset_fill_inbuf);
 618
 619 /* Initialize the b-channel structure */
 620 static struct bc_state *gigaset_initbcs(struct bc_state *bcs,
 621                                         struct cardstate *cs, int channel)
 622 {
 623         int i;
 624
 625         bcs->tx_skb = NULL; //FIXME -> hw part
 626
 627         skb_queue_head_init(&bcs->squeue);
 628
 629         bcs->corrupted = 0;
 630         bcs->trans_down = 0;
 631         bcs->trans_up = 0;
 632
 633         gig_dbg(DEBUG_INIT, "setting up bcs[%d]->at_state", channel);
 634         gigaset_at_init(&bcs->at_state, bcs, cs, -1);
 635
 636 #ifdef CONFIG_GIGASET_DEBUG
 637         bcs->emptycount = 0;
 638 #endif
 639
 640         gig_dbg(DEBUG_INIT, "allocating bcs[%d]->skb", channel);
 641         bcs->fcs = PPP_INITFCS;
 642         bcs->inputstate = 0;
 643         if (cs->ignoreframes) {
 644                 bcs->skb = NULL;
 645         } else {
 646                 bcs->skb = dev_alloc_skb(SBUFSIZE + cs->hw_hdr_len);
 647                 if (bcs->skb != NULL)
 648                         skb_reserve(bcs->skb, cs->hw_hdr_len);
 649                 else
 650                         pr_err("out of memory\n");
 651         }
 652
 653         bcs->channel = channel;
 654         bcs->cs = cs;
 655
 656         bcs->chstate = 0;
 657         bcs->use_count = 1;
 658         bcs->busy = 0;
 659         bcs->ignore = cs->ignoreframes;
 660
 661         for (i = 0; i < AT_NUM; ++i)
 662                 bcs->commands[i] = NULL;
 663
 664         gig_dbg(DEBUG_INIT, "  setting up bcs[%d]->hw", channel);
 665         if (cs->ops->initbcshw(bcs))
 666                 return bcs;
 667
 668         gig_dbg(DEBUG_INIT, "  failed");
 669
 670         gig_dbg(DEBUG_INIT, "  freeing bcs[%d]->skb", channel);
 671         dev_kfree_skb(bcs->skb);
 672         bcs->skb = NULL;
 673
 674         return NULL;
 675 }
 676
 677 /**
 678  * gigaset_initcs() - initialize device structure
 679  * @drv:        hardware driver the device belongs to
 680  * @channels:   number of B channels supported by device
 681  * @onechannel: !=0 if B channel data and AT commands share one
 682  *                  communication channel (M10x),
 683  *              ==0 if B channels have separate communication channels (base)
 684  * @ignoreframes:       number of frames to ignore after setting up B channel
 685  * @cidmode:    !=0: start in CallID mode
 686  * @modulename: name of driver module for LL registration
 687  *
 688  * Allocate and initialize cardstate structure for Gigaset driver
 689  * Calls hardware dependent gigaset_initcshw() function
 690  * Calls B channel initialization function gigaset_initbcs() for each B channel
 691  *
 692  * Return value:
 693  *      pointer to cardstate structure
 694  */
 695 struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 696                                  int onechannel, int ignoreframes,
 697                                  int cidmode, const char *modulename)
 698 {
 699         struct cardstate *cs = NULL;
 700         unsigned long flags;
 701         int i;
 702
 703         gig_dbg(DEBUG_INIT, "allocating cs");
 704         if (!(cs = alloc_cs(drv))) {
 705                 pr_err("maximum number of devices exceeded\n");
 706                 return NULL;
 707         }
 708
 709         gig_dbg(DEBUG_INIT, "allocating bcs[0..%d]", channels - 1);
 710         cs->bcs = kmalloc(channels * sizeof(struct bc_state), GFP_KERNEL);
 711         if (!cs->bcs) {
 712                 pr_err("out of memory\n");
 713                 goto error;
 714         }
 715         gig_dbg(DEBUG_INIT, "allocating inbuf");
 716         cs->inbuf = kmalloc(sizeof(struct inbuf_t), GFP_KERNEL);
 717         if (!cs->inbuf) {
 718                 pr_err("out of memory\n");
 719                 goto error;
 720         }
 721
 722         cs->cs_init = 0;
 723         cs->channels = channels;
 724         cs->onechannel = onechannel;
 725         cs->ignoreframes = ignoreframes;
 726         INIT_LIST_HEAD(&cs->temp_at_states);
 727         cs->running = 0;
 728         init_timer(&cs->timer); /* clear next & prev */
 729         spin_lock_init(&cs->ev_lock);
 730         cs->ev_tail = 0;
 731         cs->ev_head = 0;
 732
 733         tasklet_init(&cs->event_tasklet, &gigaset_handle_event,
 734                      (unsigned long) cs);
 735         cs->commands_pending = 0;
 736         cs->cur_at_seq = 0;
 737         cs->gotfwver = -1;
 738         cs->open_count = 0;
 739         cs->dev = NULL;
 740         cs->tty = NULL;
 741         cs->tty_dev = NULL;
 742         cs->cidmode = cidmode != 0;
 743         cs->tabnocid = gigaset_tab_nocid;
 744         cs->tabcid = gigaset_tab_cid;
 745
 746         init_waitqueue_head(&cs->waitqueue);
 747         cs->waiting = 0;
 748
 749         cs->mode = M_UNKNOWN;
 750         cs->mstate = MS_UNINITIALIZED;
 751
 752         ++cs->cs_init;
 753
 754         gig_dbg(DEBUG_INIT, "setting up at_state");
 755         spin_lock_init(&cs->lock);
 756         gigaset_at_init(&cs->at_state, NULL, cs, 0);
 757         cs->dle = 0;
 758         cs->cbytes = 0;
 759
 760         gig_dbg(DEBUG_INIT, "setting up inbuf");
 761         gigaset_inbuf_init(cs->inbuf, cs);
 762
 763         cs->connected = 0;
 764         cs->isdn_up = 0;
 765
 766         gig_dbg(DEBUG_INIT, "setting up cmdbuf");
 767         cs->cmdbuf = cs->lastcmdbuf = NULL;
 768         spin_lock_init(&cs->cmdlock);
 769         cs->curlen = 0;
 770         cs->cmdbytes = 0;
 771
 772         gig_dbg(DEBUG_INIT, "setting up iif");
 773         if (!gigaset_isdn_register(cs, modulename)) {
 774                 pr_err("error registering ISDN device\n");
 775                 goto error;
 776         }
 777
 778         make_valid(cs, VALID_ID);
 779         ++cs->cs_init;
 780         gig_dbg(DEBUG_INIT, "setting up hw");
 781         if (!cs->ops->initcshw(cs))
 782                 goto error;
 783
 784         ++cs->cs_init;
 785
 786         /* set up character device */
 787         gigaset_if_init(cs);
 788
 789         /* set up device sysfs */
 790         gigaset_init_dev_sysfs(cs);
 791
 792         /* set up channel data structures */
 793         for (i = 0; i < channels; ++i) {
 794                 gig_dbg(DEBUG_INIT, "setting up bcs[%d]", i);
 795                 if (!gigaset_initbcs(cs->bcs + i, cs, i)) {
 796                         pr_err("could not allocate channel %d data\n", i);
 797                         goto error;
 798                 }
 799         }
 800
 801         spin_lock_irqsave(&cs->lock, flags);
 802         cs->running = 1;
 803         spin_unlock_irqrestore(&cs->lock, flags);
 804         setup_timer(&cs->timer, timer_tick, (unsigned long) cs);
 805         cs->timer.expires = jiffies + msecs_to_jiffies(GIG_TICK);
 806         /* FIXME: can jiffies increase too much until the timer is added?
 807          * Same problem(?) with mod_timer() in timer_tick(). */
 808         add_timer(&cs->timer);
 809
 810         gig_dbg(DEBUG_INIT, "cs initialized");
 811         return cs;
 812
 813 error:
 814         gig_dbg(DEBUG_INIT, "failed");
 815         gigaset_freecs(cs);
 816         return NULL;
 817 }
 818 EXPORT_SYMBOL_GPL(gigaset_initcs);
 819
 820 /* ReInitialize the b-channel structure on hangup */
 821 void gigaset_bcs_reinit(struct bc_state *bcs)
 822 {
 823         struct sk_buff *skb;
 824         struct cardstate *cs = bcs->cs;
 825         unsigned long flags;
 826
 827         while ((skb = skb_dequeue(&bcs->squeue)) != NULL)
 828                 dev_kfree_skb(skb);
 829
 830         spin_lock_irqsave(&cs->lock, flags);
 831         clear_at_state(&bcs->at_state);
 832         bcs->at_state.ConState = 0;
 833         bcs->at_state.timer_active = 0;
 834         bcs->at_state.timer_expires = 0;
 835         bcs->at_state.cid = -1;                 /* No CID defined */
 836         spin_unlock_irqrestore(&cs->lock, flags);
 837
 838         bcs->inputstate = 0;
 839
 840 #ifdef CONFIG_GIGASET_DEBUG
 841         bcs->emptycount = 0;
 842 #endif
 843
 844         bcs->fcs = PPP_INITFCS;
 845         bcs->chstate = 0;
 846
 847         bcs->ignore = cs->ignoreframes;
 848         if (bcs->ignore) {
 849                 dev_kfree_skb(bcs->skb);
 850                 bcs->skb = NULL;
 851         }
 852
 853         cs->ops->reinitbcshw(bcs);
 854 }
 855
 856 static void cleanup_cs(struct cardstate *cs)
 857 {
 858         struct cmdbuf_t *cb, *tcb;
 859         int i;
 860         unsigned long flags;
 861
 862         spin_lock_irqsave(&cs->lock, flags);
 863
 864         cs->mode = M_UNKNOWN;
 865         cs->mstate = MS_UNINITIALIZED;
 866
 867         clear_at_state(&cs->at_state);
 868         dealloc_at_states(cs);
 869         free_strings(&cs->at_state);
 870         gigaset_at_init(&cs->at_state, NULL, cs, 0);
 871
 872         cs->inbuf->inputstate = INS_command;
 873         cs->inbuf->head = 0;
 874         cs->inbuf->tail = 0;
 875
 876         cb = cs->cmdbuf;
 877         while (cb) {
 878                 tcb = cb;
 879                 cb = cb->next;
 880                 kfree(tcb);
 881         }
 882         cs->cmdbuf = cs->lastcmdbuf = NULL;
 883         cs->curlen = 0;
 884         cs->cmdbytes = 0;
 885         cs->gotfwver = -1;
 886         cs->dle = 0;
 887         cs->cur_at_seq = 0;
 888         cs->commands_pending = 0;
 889         cs->cbytes = 0;
 890
 891         spin_unlock_irqrestore(&cs->lock, flags);
 892
 893         for (i = 0; i < cs->channels; ++i) {
 894                 gigaset_freebcs(cs->bcs + i);
 895                 if (!gigaset_initbcs(cs->bcs + i, cs, i))
 896                         pr_err("could not allocate channel %d data\n", i);
 897         }
 898
 899         if (cs->waiting) {
 900                 cs->cmd_result = -ENODEV;
 901                 cs->waiting = 0;
 902                 wake_up_interruptible(&cs->waitqueue);
 903         }
 904 }
 905
 906
 907 /**
 908  * gigaset_start() - start device operations
 909  * @cs:         device descriptor structure.
 910  *
 911  * Prepares the device for use by setting up communication parameters,
 912  * scheduling an EV_START event to initiate device initialization, and
 913  * waiting for completion of the initialization.
 914  *
 915  * Return value:
 916  *      1 - success, 0 - error
 917  */
 918 int gigaset_start(struct cardstate *cs)
 919 {
 920         unsigned long flags;
 921
 922         if (mutex_lock_interruptible(&cs->mutex))
 923                 return 0;
 924
 925         spin_lock_irqsave(&cs->lock, flags);
 926         cs->connected = 1;
 927         spin_unlock_irqrestore(&cs->lock, flags);
 928
 929         if (cs->mstate != MS_LOCKED) {
 930                 cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
 931                 cs->ops->baud_rate(cs, B115200);
 932                 cs->ops->set_line_ctrl(cs, CS8);
 933                 cs->control_state = TIOCM_DTR|TIOCM_RTS;
 934         } else {
 935                 //FIXME use some saved values?
 936         }
 937
 938         cs->waiting = 1;
 939
 940         if (!gigaset_add_event(cs, &cs->at_state, EV_START, NULL, 0, NULL)) {
 941                 cs->waiting = 0;
 942                 //FIXME what should we do?
 943                 goto error;
 944         }
 945
 946         gig_dbg(DEBUG_CMD, "scheduling START");
 947         gigaset_schedule_event(cs);
 948
 949         wait_event(cs->waitqueue, !cs->waiting);
 950
 951         mutex_unlock(&cs->mutex);
 952         return 1;
 953
 954 error:
 955         mutex_unlock(&cs->mutex);
 956         return 0;
 957 }
 958 EXPORT_SYMBOL_GPL(gigaset_start);
 959
 960 /**
 961  * gigaset_shutdown() - shut down device operations
 962  * @cs:         device descriptor structure.
 963  *
 964  * Deactivates the device by scheduling an EV_SHUTDOWN event and
 965  * waiting for completion of the shutdown.
 966  *
 967  * Return value:
 968  *      0 - success, -1 - error (no device associated)
 969  */
 970 int gigaset_shutdown(struct cardstate *cs)
 971 {
 972         mutex_lock(&cs->mutex);
 973
 974         if (!(cs->flags & VALID_MINOR)) {
 975                 mutex_unlock(&cs->mutex);
 976                 return -1;
 977         }
 978
 979         cs->waiting = 1;
 980
 981         if (!gigaset_add_event(cs, &cs->at_state, EV_SHUTDOWN, NULL, 0, NULL)) {
 982                 //FIXME what should we do?
 983                 goto exit;
 984         }
 985
 986         gig_dbg(DEBUG_CMD, "scheduling SHUTDOWN");
 987         gigaset_schedule_event(cs);
 988
 989         wait_event(cs->waitqueue, !cs->waiting);
 990
 991         cleanup_cs(cs);
 992
 993 exit:
 994         mutex_unlock(&cs->mutex);
 995         return 0;
 996 }
 997 EXPORT_SYMBOL_GPL(gigaset_shutdown);
 998
 999 /**
1000  * gigaset_stop() - stop device operations
1001  * @cs:         device descriptor structure.
1002  *
1003  * Stops operations on the device by scheduling an EV_STOP event and
1004  * waiting for completion of the shutdown.
1005  */
1006 void gigaset_stop(struct cardstate *cs)
1007 {
1008         mutex_lock(&cs->mutex);
1009
1010         cs->waiting = 1;
1011
1012         if (!gigaset_add_event(cs, &cs->at_state, EV_STOP, NULL, 0, NULL)) {
1013                 //FIXME what should we do?
1014                 goto exit;
1015         }
1016
1017         gig_dbg(DEBUG_CMD, "scheduling STOP");
1018         gigaset_schedule_event(cs);
1019
1020         wait_event(cs->waitqueue, !cs->waiting);
1021
1022         cleanup_cs(cs);
1023
1024 exit:
1025         mutex_unlock(&cs->mutex);
1026 }
1027 EXPORT_SYMBOL_GPL(gigaset_stop);
1028
1029 static LIST_HEAD(drivers);
1030 static DEFINE_SPINLOCK(driver_lock);
1031
1032 struct cardstate *gigaset_get_cs_by_id(int id)
1033 {
1034         unsigned long flags;
1035         struct cardstate *ret = NULL;
1036         struct cardstate *cs;
1037         struct gigaset_driver *drv;
1038         unsigned i;
1039
1040         spin_lock_irqsave(&driver_lock, flags);
1041         list_for_each_entry(drv, &drivers, list) {
1042                 spin_lock(&drv->lock);
1043                 for (i = 0; i < drv->minors; ++i) {
1044                         cs = drv->cs + i;
1045                         if ((cs->flags & VALID_ID) && cs->myid == id) {
1046                                 ret = cs;
1047                                 break;
1048                         }
1049                 }
1050                 spin_unlock(&drv->lock);
1051                 if (ret)
1052                         break;
1053         }
1054         spin_unlock_irqrestore(&driver_lock, flags);
1055         return ret;
1056 }
1057
1058 void gigaset_debugdrivers(void)
1059 {
1060         unsigned long flags;
1061         static struct cardstate *cs;
1062         struct gigaset_driver *drv;
1063         unsigned i;
1064
1065         spin_lock_irqsave(&driver_lock, flags);
1066         list_for_each_entry(drv, &drivers, list) {
1067                 gig_dbg(DEBUG_DRIVER, "driver %p", drv);
1068                 spin_lock(&drv->lock);
1069                 for (i = 0; i < drv->minors; ++i) {
1070                         gig_dbg(DEBUG_DRIVER, "  index %u", i);
1071                         cs = drv->cs + i;
1072                         gig_dbg(DEBUG_DRIVER, "    cardstate %p", cs);
1073                         gig_dbg(DEBUG_DRIVER, "    flags 0x%02x", cs->flags);
1074                         gig_dbg(DEBUG_DRIVER, "    minor_index %u",
1075                                 cs->minor_index);
1076                         gig_dbg(DEBUG_DRIVER, "    driver %p", cs->driver);
1077                         gig_dbg(DEBUG_DRIVER, "    i4l id %d", cs->myid);
1078                 }
1079                 spin_unlock(&drv->lock);
1080         }
1081         spin_unlock_irqrestore(&driver_lock, flags);
1082 }
1083
1084 static struct cardstate *gigaset_get_cs_by_minor(unsigned minor)
1085 {
1086         unsigned long flags;
1087         struct cardstate *ret = NULL;
1088         struct gigaset_driver *drv;
1089         unsigned index;
1090
1091         spin_lock_irqsave(&driver_lock, flags);
1092         list_for_each_entry(drv, &drivers, list) {
1093                 if (minor < drv->minor || minor >= drv->minor + drv->minors)
1094                         continue;
1095                 index = minor - drv->minor;
1096                 spin_lock(&drv->lock);
1097                 if (drv->cs[index].flags & VALID_MINOR)
1098                         ret = drv->cs + index;
1099                 spin_unlock(&drv->lock);
1100                 if (ret)
1101                         break;
1102         }
1103         spin_unlock_irqrestore(&driver_lock, flags);
1104         return ret;
1105 }
1106
1107 struct cardstate *gigaset_get_cs_by_tty(struct tty_struct *tty)
1108 {
1109         if (tty->index < 0 || tty->index >= tty->driver->num)
1110                 return NULL;
1111         return gigaset_get_cs_by_minor(tty->index + tty->driver->minor_start);
1112 }
1113
1114 /**
1115  * gigaset_freedriver() - free all associated ressources of a driver
1116  * @drv:        driver descriptor structure.
1117  *
1118  * Unregisters the driver from the system and deallocates the driver
1119  * structure @drv and all structures referenced from it.
1120  * All devices should be shut down before calling this.
1121  */
1122 void gigaset_freedriver(struct gigaset_driver *drv)
1123 {
1124         unsigned long flags;
1125
1126         spin_lock_irqsave(&driver_lock, flags);
1127         list_del(&drv->list);
1128         spin_unlock_irqrestore(&driver_lock, flags);
1129
1130         gigaset_if_freedriver(drv);
1131
1132         kfree(drv->cs);
1133         kfree(drv);
1134 }
1135 EXPORT_SYMBOL_GPL(gigaset_freedriver);
1136
1137 /**
1138  * gigaset_initdriver() - initialize driver structure
1139  * @minor:      First minor number
1140  * @minors:     Number of minors this driver can handle
1141  * @procname:   Name of the driver
1142  * @devname:    Name of the device files (prefix without minor number)
1143  *
1144  * Allocate and initialize gigaset_driver structure. Initialize interface.
1145  *
1146  * Return value:
1147  *      Pointer to the gigaset_driver structure on success, NULL on failure.
1148  */
1149 struct gigaset_driver *gigaset_initdriver(unsigned minor, unsigned minors,
1150                                           const char *procname,
1151                                           const char *devname,
1152                                           const struct gigaset_ops *ops,
1153                                           struct module *owner)
1154 {
1155         struct gigaset_driver *drv;
1156         unsigned long flags;
1157         unsigned i;
1158
1159         drv = kmalloc(sizeof *drv, GFP_KERNEL);
1160         if (!drv)
1161                 return NULL;
1162
1163         drv->have_tty = 0;
1164         drv->minor = minor;
1165         drv->minors = minors;
1166         spin_lock_init(&drv->lock);
1167         drv->blocked = 0;
1168         drv->ops = ops;
1169         drv->owner = owner;
1170         INIT_LIST_HEAD(&drv->list);
1171
1172         drv->cs = kmalloc(minors * sizeof *drv->cs, GFP_KERNEL);
1173         if (!drv->cs)
1174                 goto error;
1175
1176         for (i = 0; i < minors; ++i) {
1177                 drv->cs[i].flags = 0;
1178                 drv->cs[i].driver = drv;
1179                 drv->cs[i].ops = drv->ops;
1180                 drv->cs[i].minor_index = i;
1181                 mutex_init(&drv->cs[i].mutex);
1182         }
1183
1184         gigaset_if_initdriver(drv, procname, devname);
1185
1186         spin_lock_irqsave(&driver_lock, flags);
1187         list_add(&drv->list, &drivers);
1188         spin_unlock_irqrestore(&driver_lock, flags);
1189
1190         return drv;
1191
1192 error:
1193         kfree(drv->cs);
1194         kfree(drv);
1195         return NULL;
1196 }
1197 EXPORT_SYMBOL_GPL(gigaset_initdriver);
1198
1199 /**
1200  * gigaset_blockdriver() - block driver
1201  * @drv:        driver descriptor structure.
1202  *
1203  * Prevents the driver from attaching new devices, in preparation for
1204  * deregistration.
1205  */
1206 void gigaset_blockdriver(struct gigaset_driver *drv)
1207 {
1208         drv->blocked = 1;
1209 }
1210 EXPORT_SYMBOL_GPL(gigaset_blockdriver);
1211
1212 static int __init gigaset_init_module(void)
1213 {
1214         /* in accordance with the principle of least astonishment,
1215          * setting the 'debug' parameter to 1 activates a sensible
1216          * set of default debug levels
1217          */
1218         if (gigaset_debuglevel == 1)
1219                 gigaset_debuglevel = DEBUG_DEFAULT;
1220
1221         pr_info(DRIVER_DESC DRIVER_DESC_DEBUG "\n");
1222         return 0;
1223 }
1224
1225 static void __exit gigaset_exit_module(void)
1226 {
1227 }
1228
1229 module_init(gigaset_init_module);
1230 module_exit(gigaset_exit_module);
1231
1232 MODULE_AUTHOR(DRIVER_AUTHOR);
1233 MODULE_DESCRIPTION(DRIVER_DESC);
1234
1235 MODULE_LICENSE("GPL");