Pileus Git - ~andy/linux/blob - net/nfc/core.c

   1 /*
   2  * Copyright (C) 2011 Instituto Nokia de Tecnologia
   3  *
   4  * Authors:
   5  *    Lauro Ramos Venancio <lauro.venancio@openbossa.org>
   6  *    Aloisio Almeida Jr <aloisio.almeida@openbossa.org>
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the
  20  * Free Software Foundation, Inc.,
  21  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  22  */
  23
  24 #define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
  25
  26 #include <linux/init.h>
  27 #include <linux/kernel.h>
  28 #include <linux/module.h>
  29 #include <linux/slab.h>
  30 #include <linux/nfc.h>
  31
  32 #include "nfc.h"
  33
  34 #define VERSION "0.1"
  35
  36 #define NFC_CHECK_PRES_FREQ_MS  2000
  37
  38 int nfc_devlist_generation;
  39 DEFINE_MUTEX(nfc_devlist_mutex);
  40
  41 /**
  42  * nfc_dev_up - turn on the NFC device
  43  *
  44  * @dev: The nfc device to be turned on
  45  *
  46  * The device remains up until the nfc_dev_down function is called.
  47  */
  48 int nfc_dev_up(struct nfc_dev *dev)
  49 {
  50         int rc = 0;
  51
  52         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
  53
  54         device_lock(&dev->dev);
  55
  56         if (!device_is_registered(&dev->dev)) {
  57                 rc = -ENODEV;
  58                 goto error;
  59         }
  60
  61         if (dev->dev_up) {
  62                 rc = -EALREADY;
  63                 goto error;
  64         }
  65
  66         if (dev->ops->dev_up)
  67                 rc = dev->ops->dev_up(dev);
  68
  69         if (!rc)
  70                 dev->dev_up = true;
  71
  72 error:
  73         device_unlock(&dev->dev);
  74         return rc;
  75 }
  76
  77 /**
  78  * nfc_dev_down - turn off the NFC device
  79  *
  80  * @dev: The nfc device to be turned off
  81  */
  82 int nfc_dev_down(struct nfc_dev *dev)
  83 {
  84         int rc = 0;
  85
  86         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
  87
  88         device_lock(&dev->dev);
  89
  90         if (!device_is_registered(&dev->dev)) {
  91                 rc = -ENODEV;
  92                 goto error;
  93         }
  94
  95         if (!dev->dev_up) {
  96                 rc = -EALREADY;
  97                 goto error;
  98         }
  99
 100         if (dev->polling || dev->activated_target_idx != NFC_TARGET_IDX_NONE) {
 101                 rc = -EBUSY;
 102                 goto error;
 103         }
 104
 105         if (dev->ops->dev_down)
 106                 dev->ops->dev_down(dev);
 107
 108         dev->dev_up = false;
 109
 110 error:
 111         device_unlock(&dev->dev);
 112         return rc;
 113 }
 114
 115 /**
 116  * nfc_start_poll - start polling for nfc targets
 117  *
 118  * @dev: The nfc device that must start polling
 119  * @protocols: bitset of nfc protocols that must be used for polling
 120  *
 121  * The device remains polling for targets until a target is found or
 122  * the nfc_stop_poll function is called.
 123  */
 124 int nfc_start_poll(struct nfc_dev *dev, u32 protocols)
 125 {
 126         int rc;
 127
 128         pr_debug("dev_name=%s protocols=0x%x\n",
 129                  dev_name(&dev->dev), protocols);
 130
 131         if (!protocols)
 132                 return -EINVAL;
 133
 134         device_lock(&dev->dev);
 135
 136         if (!device_is_registered(&dev->dev)) {
 137                 rc = -ENODEV;
 138                 goto error;
 139         }
 140
 141         if (dev->polling) {
 142                 rc = -EBUSY;
 143                 goto error;
 144         }
 145
 146         rc = dev->ops->start_poll(dev, protocols);
 147         if (!rc)
 148                 dev->polling = true;
 149
 150 error:
 151         device_unlock(&dev->dev);
 152         return rc;
 153 }
 154
 155 /**
 156  * nfc_stop_poll - stop polling for nfc targets
 157  *
 158  * @dev: The nfc device that must stop polling
 159  */
 160 int nfc_stop_poll(struct nfc_dev *dev)
 161 {
 162         int rc = 0;
 163
 164         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 165
 166         device_lock(&dev->dev);
 167
 168         if (!device_is_registered(&dev->dev)) {
 169                 rc = -ENODEV;
 170                 goto error;
 171         }
 172
 173         if (!dev->polling) {
 174                 rc = -EINVAL;
 175                 goto error;
 176         }
 177
 178         dev->ops->stop_poll(dev);
 179         dev->polling = false;
 180
 181 error:
 182         device_unlock(&dev->dev);
 183         return rc;
 184 }
 185
 186 int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
 187 {
 188         int rc = 0;
 189         u8 *gb;
 190         size_t gb_len;
 191
 192         pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode);
 193
 194         if (!dev->ops->dep_link_up)
 195                 return -EOPNOTSUPP;
 196
 197         device_lock(&dev->dev);
 198
 199         if (!device_is_registered(&dev->dev)) {
 200                 rc = -ENODEV;
 201                 goto error;
 202         }
 203
 204         if (dev->dep_link_up == true) {
 205                 rc = -EALREADY;
 206                 goto error;
 207         }
 208
 209         gb = nfc_llcp_general_bytes(dev, &gb_len);
 210         if (gb_len > NFC_MAX_GT_LEN) {
 211                 rc = -EINVAL;
 212                 goto error;
 213         }
 214
 215         rc = dev->ops->dep_link_up(dev, target_index, comm_mode, gb, gb_len);
 216         if (!rc)
 217                 dev->activated_target_idx = target_index;
 218
 219 error:
 220         device_unlock(&dev->dev);
 221         return rc;
 222 }
 223
 224 int nfc_dep_link_down(struct nfc_dev *dev)
 225 {
 226         int rc = 0;
 227
 228         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 229
 230         if (!dev->ops->dep_link_down)
 231                 return -EOPNOTSUPP;
 232
 233         device_lock(&dev->dev);
 234
 235         if (!device_is_registered(&dev->dev)) {
 236                 rc = -ENODEV;
 237                 goto error;
 238         }
 239
 240         if (dev->dep_link_up == false) {
 241                 rc = -EALREADY;
 242                 goto error;
 243         }
 244
 245         if (dev->dep_rf_mode == NFC_RF_TARGET) {
 246                 rc = -EOPNOTSUPP;
 247                 goto error;
 248         }
 249
 250         rc = dev->ops->dep_link_down(dev);
 251         if (!rc) {
 252                 dev->dep_link_up = false;
 253                 dev->activated_target_idx = NFC_TARGET_IDX_NONE;
 254                 nfc_llcp_mac_is_down(dev);
 255                 nfc_genl_dep_link_down_event(dev);
 256         }
 257
 258 error:
 259         device_unlock(&dev->dev);
 260         return rc;
 261 }
 262
 263 int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
 264                        u8 comm_mode, u8 rf_mode)
 265 {
 266         dev->dep_link_up = true;
 267         dev->dep_rf_mode = rf_mode;
 268
 269         nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode);
 270
 271         return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode);
 272 }
 273 EXPORT_SYMBOL(nfc_dep_link_is_up);
 274
 275 /**
 276  * nfc_activate_target - prepare the target for data exchange
 277  *
 278  * @dev: The nfc device that found the target
 279  * @target_idx: index of the target that must be activated
 280  * @protocol: nfc protocol that will be used for data exchange
 281  */
 282 int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
 283 {
 284         int rc;
 285
 286         pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
 287                  dev_name(&dev->dev), target_idx, protocol);
 288
 289         device_lock(&dev->dev);
 290
 291         if (!device_is_registered(&dev->dev)) {
 292                 rc = -ENODEV;
 293                 goto error;
 294         }
 295
 296         rc = dev->ops->activate_target(dev, target_idx, protocol);
 297         if (!rc) {
 298                 dev->activated_target_idx = target_idx;
 299
 300                 if (dev->ops->check_presence)
 301                         mod_timer(&dev->check_pres_timer, jiffies +
 302                                   msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
 303         }
 304
 305 error:
 306         device_unlock(&dev->dev);
 307         return rc;
 308 }
 309
 310 /**
 311  * nfc_deactivate_target - deactivate a nfc target
 312  *
 313  * @dev: The nfc device that found the target
 314  * @target_idx: index of the target that must be deactivated
 315  */
 316 int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
 317 {
 318         int rc = 0;
 319
 320         pr_debug("dev_name=%s target_idx=%u\n",
 321                  dev_name(&dev->dev), target_idx);
 322
 323         device_lock(&dev->dev);
 324
 325         if (!device_is_registered(&dev->dev)) {
 326                 rc = -ENODEV;
 327                 goto error;
 328         }
 329
 330         if (dev->ops->check_presence)
 331                 del_timer_sync(&dev->check_pres_timer);
 332
 333         dev->ops->deactivate_target(dev, target_idx);
 334         dev->activated_target_idx = NFC_TARGET_IDX_NONE;
 335
 336 error:
 337         device_unlock(&dev->dev);
 338         return rc;
 339 }
 340
 341 /**
 342  * nfc_data_exchange - transceive data
 343  *
 344  * @dev: The nfc device that found the target
 345  * @target_idx: index of the target
 346  * @skb: data to be sent
 347  * @cb: callback called when the response is received
 348  * @cb_context: parameter for the callback function
 349  *
 350  * The user must wait for the callback before calling this function again.
 351  */
 352 int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
 353                       data_exchange_cb_t cb, void *cb_context)
 354 {
 355         int rc;
 356
 357         pr_debug("dev_name=%s target_idx=%u skb->len=%u\n",
 358                  dev_name(&dev->dev), target_idx, skb->len);
 359
 360         device_lock(&dev->dev);
 361
 362         if (!device_is_registered(&dev->dev)) {
 363                 rc = -ENODEV;
 364                 kfree_skb(skb);
 365                 goto error;
 366         }
 367
 368         if (dev->activated_target_idx == NFC_TARGET_IDX_NONE) {
 369                 rc = -ENOTCONN;
 370                 kfree_skb(skb);
 371                 goto error;
 372         }
 373
 374         if (target_idx != dev->activated_target_idx) {
 375                 rc = -EADDRNOTAVAIL;
 376                 kfree_skb(skb);
 377                 goto error;
 378         }
 379
 380         if (dev->ops->check_presence)
 381                 del_timer_sync(&dev->check_pres_timer);
 382
 383         rc = dev->ops->data_exchange(dev, target_idx, skb, cb, cb_context);
 384
 385         if (!rc && dev->ops->check_presence)
 386                 mod_timer(&dev->check_pres_timer, jiffies +
 387                           msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
 388
 389 error:
 390         device_unlock(&dev->dev);
 391         return rc;
 392 }
 393
 394 int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
 395 {
 396         pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
 397
 398         if (gb_len > NFC_MAX_GT_LEN)
 399                 return -EINVAL;
 400
 401         return nfc_llcp_set_remote_gb(dev, gb, gb_len);
 402 }
 403 EXPORT_SYMBOL(nfc_set_remote_general_bytes);
 404
 405 /**
 406  * nfc_alloc_send_skb - allocate a skb for data exchange responses
 407  *
 408  * @size: size to allocate
 409  * @gfp: gfp flags
 410  */
 411 struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk,
 412                                    unsigned int flags, unsigned int size,
 413                                    unsigned int *err)
 414 {
 415         struct sk_buff *skb;
 416         unsigned int total_size;
 417
 418         total_size = size +
 419                 dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 420
 421         skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err);
 422         if (skb)
 423                 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 424
 425         return skb;
 426 }
 427
 428 /**
 429  * nfc_alloc_recv_skb - allocate a skb for data exchange responses
 430  *
 431  * @size: size to allocate
 432  * @gfp: gfp flags
 433  */
 434 struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp)
 435 {
 436         struct sk_buff *skb;
 437         unsigned int total_size;
 438
 439         total_size = size + 1;
 440         skb = alloc_skb(total_size, gfp);
 441
 442         if (skb)
 443                 skb_reserve(skb, 1);
 444
 445         return skb;
 446 }
 447 EXPORT_SYMBOL(nfc_alloc_recv_skb);
 448
 449 /**
 450  * nfc_targets_found - inform that targets were found
 451  *
 452  * @dev: The nfc device that found the targets
 453  * @targets: array of nfc targets found
 454  * @ntargets: targets array size
 455  *
 456  * The device driver must call this function when one or many nfc targets
 457  * are found. After calling this function, the device driver must stop
 458  * polling for targets.
 459  */
 460 int nfc_targets_found(struct nfc_dev *dev,
 461                       struct nfc_target *targets, int n_targets)
 462 {
 463         int i;
 464
 465         pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets);
 466
 467         dev->polling = false;
 468
 469         for (i = 0; i < n_targets; i++)
 470                 targets[i].idx = dev->target_next_idx++;
 471
 472         spin_lock_bh(&dev->targets_lock);
 473
 474         dev->targets_generation++;
 475
 476         kfree(dev->targets);
 477         dev->targets = kmemdup(targets, n_targets * sizeof(struct nfc_target),
 478                                GFP_ATOMIC);
 479
 480         if (!dev->targets) {
 481                 dev->n_targets = 0;
 482                 spin_unlock_bh(&dev->targets_lock);
 483                 return -ENOMEM;
 484         }
 485
 486         dev->n_targets = n_targets;
 487         spin_unlock_bh(&dev->targets_lock);
 488
 489         nfc_genl_targets_found(dev);
 490
 491         return 0;
 492 }
 493 EXPORT_SYMBOL(nfc_targets_found);
 494
 495 int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
 496 {
 497         struct nfc_target *tg;
 498         int i;
 499
 500         pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx);
 501
 502         spin_lock_bh(&dev->targets_lock);
 503
 504         for (i = 0; i < dev->n_targets; i++) {
 505                 tg = &dev->targets[i];
 506                 if (tg->idx == target_idx)
 507                         break;
 508         }
 509
 510         if (i == dev->n_targets) {
 511                 spin_unlock_bh(&dev->targets_lock);
 512                 return -EINVAL;
 513         }
 514
 515         dev->targets_generation++;
 516         dev->n_targets--;
 517         dev->activated_target_idx = NFC_TARGET_IDX_NONE;
 518
 519         if (dev->n_targets) {
 520                 memcpy(&dev->targets[i], &dev->targets[i + 1],
 521                        (dev->n_targets - i) * sizeof(struct nfc_target));
 522         } else {
 523                 kfree(dev->targets);
 524                 dev->targets = NULL;
 525         }
 526
 527         spin_unlock_bh(&dev->targets_lock);
 528
 529         nfc_genl_target_lost(dev, target_idx);
 530
 531         return 0;
 532 }
 533 EXPORT_SYMBOL(nfc_target_lost);
 534
 535 static void nfc_release(struct device *d)
 536 {
 537         struct nfc_dev *dev = to_nfc_dev(d);
 538
 539         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 540
 541         if (dev->ops->check_presence) {
 542                 del_timer_sync(&dev->check_pres_timer);
 543                 destroy_workqueue(dev->check_pres_wq);
 544         }
 545
 546         nfc_genl_data_exit(&dev->genl_data);
 547         kfree(dev->targets);
 548         kfree(dev);
 549 }
 550
 551 static void nfc_check_pres_work(struct work_struct *work)
 552 {
 553         struct nfc_dev *dev = container_of(work, struct nfc_dev,
 554                                            check_pres_work);
 555         int rc;
 556
 557         device_lock(&dev->dev);
 558
 559         if (dev->activated_target_idx != NFC_TARGET_IDX_NONE &&
 560             timer_pending(&dev->check_pres_timer) == 0) {
 561                 rc = dev->ops->check_presence(dev, dev->activated_target_idx);
 562                 if (!rc) {
 563                         mod_timer(&dev->check_pres_timer, jiffies +
 564                                   msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
 565                 } else {
 566                         nfc_target_lost(dev, dev->activated_target_idx);
 567                         dev->activated_target_idx = NFC_TARGET_IDX_NONE;
 568                 }
 569         }
 570
 571         device_unlock(&dev->dev);
 572 }
 573
 574 static void nfc_check_pres_timeout(unsigned long data)
 575 {
 576         struct nfc_dev *dev = (struct nfc_dev *)data;
 577
 578         queue_work(dev->check_pres_wq, &dev->check_pres_work);
 579 }
 580
 581 struct class nfc_class = {
 582         .name = "nfc",
 583         .dev_release = nfc_release,
 584 };
 585 EXPORT_SYMBOL(nfc_class);
 586
 587 static int match_idx(struct device *d, void *data)
 588 {
 589         struct nfc_dev *dev = to_nfc_dev(d);
 590         unsigned int *idx = data;
 591
 592         return dev->idx == *idx;
 593 }
 594
 595 struct nfc_dev *nfc_get_device(unsigned int idx)
 596 {
 597         struct device *d;
 598
 599         d = class_find_device(&nfc_class, NULL, &idx, match_idx);
 600         if (!d)
 601                 return NULL;
 602
 603         return to_nfc_dev(d);
 604 }
 605
 606 /**
 607  * nfc_allocate_device - allocate a new nfc device
 608  *
 609  * @ops: device operations
 610  * @supported_protocols: NFC protocols supported by the device
 611  */
 612 struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
 613                                     u32 supported_protocols,
 614                                     int tx_headroom, int tx_tailroom)
 615 {
 616         static atomic_t dev_no = ATOMIC_INIT(0);
 617         struct nfc_dev *dev;
 618
 619         if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
 620             !ops->deactivate_target || !ops->data_exchange)
 621                 return NULL;
 622
 623         if (!supported_protocols)
 624                 return NULL;
 625
 626         dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
 627         if (!dev)
 628                 return NULL;
 629
 630         dev->dev.class = &nfc_class;
 631         dev->idx = atomic_inc_return(&dev_no) - 1;
 632         dev_set_name(&dev->dev, "nfc%d", dev->idx);
 633         device_initialize(&dev->dev);
 634
 635         dev->ops = ops;
 636         dev->supported_protocols = supported_protocols;
 637         dev->tx_headroom = tx_headroom;
 638         dev->tx_tailroom = tx_tailroom;
 639
 640         spin_lock_init(&dev->targets_lock);
 641         nfc_genl_data_init(&dev->genl_data);
 642
 643         /* first generation must not be 0 */
 644         dev->targets_generation = 1;
 645
 646         dev->activated_target_idx = NFC_TARGET_IDX_NONE;
 647
 648         if (ops->check_presence) {
 649                 char name[32];
 650                 init_timer(&dev->check_pres_timer);
 651                 dev->check_pres_timer.data = (unsigned long)dev;
 652                 dev->check_pres_timer.function = nfc_check_pres_timeout;
 653
 654                 INIT_WORK(&dev->check_pres_work, nfc_check_pres_work);
 655                 snprintf(name, sizeof(name), "nfc%d_check_pres_wq", dev->idx);
 656                 dev->check_pres_wq = alloc_workqueue(name, WQ_NON_REENTRANT |
 657                                                      WQ_UNBOUND |
 658                                                      WQ_MEM_RECLAIM, 1);
 659                 if (dev->check_pres_wq == NULL) {
 660                         kfree(dev);
 661                         return NULL;
 662                 }
 663         }
 664
 665
 666         return dev;
 667 }
 668 EXPORT_SYMBOL(nfc_allocate_device);
 669
 670 /**
 671  * nfc_register_device - register a nfc device in the nfc subsystem
 672  *
 673  * @dev: The nfc device to register
 674  */
 675 int nfc_register_device(struct nfc_dev *dev)
 676 {
 677         int rc;
 678
 679         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 680
 681         mutex_lock(&nfc_devlist_mutex);
 682         nfc_devlist_generation++;
 683         rc = device_add(&dev->dev);
 684         mutex_unlock(&nfc_devlist_mutex);
 685
 686         if (rc < 0)
 687                 return rc;
 688
 689         rc = nfc_llcp_register_device(dev);
 690         if (rc)
 691                 pr_err("Could not register llcp device\n");
 692
 693         rc = nfc_genl_device_added(dev);
 694         if (rc)
 695                 pr_debug("The userspace won't be notified that the device %s was added\n",
 696                          dev_name(&dev->dev));
 697
 698         return 0;
 699 }
 700 EXPORT_SYMBOL(nfc_register_device);
 701
 702 /**
 703  * nfc_unregister_device - unregister a nfc device in the nfc subsystem
 704  *
 705  * @dev: The nfc device to unregister
 706  */
 707 void nfc_unregister_device(struct nfc_dev *dev)
 708 {
 709         int rc;
 710
 711         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 712
 713         mutex_lock(&nfc_devlist_mutex);
 714         nfc_devlist_generation++;
 715
 716         /* lock to avoid unregistering a device while an operation
 717            is in progress */
 718         device_lock(&dev->dev);
 719         device_del(&dev->dev);
 720         device_unlock(&dev->dev);
 721
 722         mutex_unlock(&nfc_devlist_mutex);
 723
 724         nfc_llcp_unregister_device(dev);
 725
 726         rc = nfc_genl_device_removed(dev);
 727         if (rc)
 728                 pr_debug("The userspace won't be notified that the device %s was removed\n",
 729                          dev_name(&dev->dev));
 730
 731 }
 732 EXPORT_SYMBOL(nfc_unregister_device);
 733
 734 static int __init nfc_init(void)
 735 {
 736         int rc;
 737
 738         pr_info("NFC Core ver %s\n", VERSION);
 739
 740         rc = class_register(&nfc_class);
 741         if (rc)
 742                 return rc;
 743
 744         rc = nfc_genl_init();
 745         if (rc)
 746                 goto err_genl;
 747
 748         /* the first generation must not be 0 */
 749         nfc_devlist_generation = 1;
 750
 751         rc = rawsock_init();
 752         if (rc)
 753                 goto err_rawsock;
 754
 755         rc = nfc_llcp_init();
 756         if (rc)
 757                 goto err_llcp_sock;
 758
 759         rc = af_nfc_init();
 760         if (rc)
 761                 goto err_af_nfc;
 762
 763         return 0;
 764
 765 err_af_nfc:
 766         nfc_llcp_exit();
 767 err_llcp_sock:
 768         rawsock_exit();
 769 err_rawsock:
 770         nfc_genl_exit();
 771 err_genl:
 772         class_unregister(&nfc_class);
 773         return rc;
 774 }
 775
 776 static void __exit nfc_exit(void)
 777 {
 778         af_nfc_exit();
 779         nfc_llcp_exit();
 780         rawsock_exit();
 781         nfc_genl_exit();
 782         class_unregister(&nfc_class);
 783 }
 784
 785 subsys_initcall(nfc_init);
 786 module_exit(nfc_exit);
 787
 788 MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
 789 MODULE_DESCRIPTION("NFC Core ver " VERSION);
 790 MODULE_VERSION(VERSION);
 791 MODULE_LICENSE("GPL");