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 <net/genetlink.h> 33 34 #include "nfc.h" 35 36 #define VERSION "0.1" 37 38 #define NFC_CHECK_PRES_FREQ_MS 2000 39 40 int nfc_devlist_generation; 41 DEFINE_MUTEX(nfc_devlist_mutex); 42 43 /** 44 * nfc_dev_up - turn on the NFC device 45 * 46 * @dev: The nfc device to be turned on 47 * 48 * The device remains up until the nfc_dev_down function is called. 49 */ 50 int nfc_dev_up(struct nfc_dev *dev) 51 { 52 int rc = 0; 53 54 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 55 56 device_lock(&dev->dev); 57 58 if (!device_is_registered(&dev->dev)) { 59 rc = -ENODEV; 60 goto error; 61 } 62 63 if (dev->dev_up) { 64 rc = -EALREADY; 65 goto error; 66 } 67 68 if (dev->ops->dev_up) 69 rc = dev->ops->dev_up(dev); 70 71 if (!rc) 72 dev->dev_up = true; 73 74 error: 75 device_unlock(&dev->dev); 76 return rc; 77 } 78 79 /** 80 * nfc_dev_down - turn off the NFC device 81 * 82 * @dev: The nfc device to be turned off 83 */ 84 int nfc_dev_down(struct nfc_dev *dev) 85 { 86 int rc = 0; 87 88 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 89 90 device_lock(&dev->dev); 91 92 if (!device_is_registered(&dev->dev)) { 93 rc = -ENODEV; 94 goto error; 95 } 96 97 if (!dev->dev_up) { 98 rc = -EALREADY; 99 goto error; 100 } 101 102 if (dev->polling || dev->active_target) { 103 rc = -EBUSY; 104 goto error; 105 } 106 107 if (dev->ops->dev_down) 108 dev->ops->dev_down(dev); 109 110 dev->dev_up = false; 111 112 error: 113 device_unlock(&dev->dev); 114 return rc; 115 } 116 117 /** 118 * nfc_start_poll - start polling for nfc targets 119 * 120 * @dev: The nfc device that must start polling 121 * @protocols: bitset of nfc protocols that must be used for polling 122 * 123 * The device remains polling for targets until a target is found or 124 * the nfc_stop_poll function is called. 125 */ 126 int nfc_start_poll(struct nfc_dev *dev, u32 im_protocols, u32 tm_protocols) 127 { 128 int rc; 129 130 pr_debug("dev_name %s initiator protocols 0x%x target protocols 0x%x\n", 131 dev_name(&dev->dev), im_protocols, tm_protocols); 132 133 if (!im_protocols && !tm_protocols) 134 return -EINVAL; 135 136 device_lock(&dev->dev); 137 138 if (!device_is_registered(&dev->dev)) { 139 rc = -ENODEV; 140 goto error; 141 } 142 143 if (dev->polling) { 144 rc = -EBUSY; 145 goto error; 146 } 147 148 rc = dev->ops->start_poll(dev, im_protocols, tm_protocols); 149 if (!rc) { 150 dev->polling = true; 151 dev->rf_mode = NFC_RF_NONE; 152 } 153 154 error: 155 device_unlock(&dev->dev); 156 return rc; 157 } 158 159 /** 160 * nfc_stop_poll - stop polling for nfc targets 161 * 162 * @dev: The nfc device that must stop polling 163 */ 164 int nfc_stop_poll(struct nfc_dev *dev) 165 { 166 int rc = 0; 167 168 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 169 170 device_lock(&dev->dev); 171 172 if (!device_is_registered(&dev->dev)) { 173 rc = -ENODEV; 174 goto error; 175 } 176 177 if (!dev->polling) { 178 rc = -EINVAL; 179 goto error; 180 } 181 182 dev->ops->stop_poll(dev); 183 dev->polling = false; 184 185 error: 186 device_unlock(&dev->dev); 187 return rc; 188 } 189 190 static struct nfc_target *nfc_find_target(struct nfc_dev *dev, u32 target_idx) 191 { 192 int i; 193 194 if (dev->n_targets == 0) 195 return NULL; 196 197 for (i = 0; i < dev->n_targets ; i++) { 198 if (dev->targets[i].idx == target_idx) 199 return &dev->targets[i]; 200 } 201 202 return NULL; 203 } 204 205 int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode) 206 { 207 int rc = 0; 208 u8 *gb; 209 size_t gb_len; 210 struct nfc_target *target; 211 212 pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode); 213 214 if (!dev->ops->dep_link_up) 215 return -EOPNOTSUPP; 216 217 device_lock(&dev->dev); 218 219 if (!device_is_registered(&dev->dev)) { 220 rc = -ENODEV; 221 goto error; 222 } 223 224 if (dev->dep_link_up == true) { 225 rc = -EALREADY; 226 goto error; 227 } 228 229 gb = nfc_llcp_general_bytes(dev, &gb_len); 230 if (gb_len > NFC_MAX_GT_LEN) { 231 rc = -EINVAL; 232 goto error; 233 } 234 235 target = nfc_find_target(dev, target_index); 236 if (target == NULL) { 237 rc = -ENOTCONN; 238 goto error; 239 } 240 241 rc = dev->ops->dep_link_up(dev, target, comm_mode, gb, gb_len); 242 if (!rc) { 243 dev->active_target = target; 244 dev->rf_mode = NFC_RF_INITIATOR; 245 } 246 247 error: 248 device_unlock(&dev->dev); 249 return rc; 250 } 251 252 int nfc_dep_link_down(struct nfc_dev *dev) 253 { 254 int rc = 0; 255 256 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 257 258 if (!dev->ops->dep_link_down) 259 return -EOPNOTSUPP; 260 261 device_lock(&dev->dev); 262 263 if (!device_is_registered(&dev->dev)) { 264 rc = -ENODEV; 265 goto error; 266 } 267 268 if (dev->dep_link_up == false) { 269 rc = -EALREADY; 270 goto error; 271 } 272 273 rc = dev->ops->dep_link_down(dev); 274 if (!rc) { 275 dev->dep_link_up = false; 276 dev->active_target = NULL; 277 nfc_llcp_mac_is_down(dev); 278 nfc_genl_dep_link_down_event(dev); 279 } 280 281 error: 282 device_unlock(&dev->dev); 283 return rc; 284 } 285 286 int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx, 287 u8 comm_mode, u8 rf_mode) 288 { 289 dev->dep_link_up = true; 290 291 nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode); 292 293 return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode); 294 } 295 EXPORT_SYMBOL(nfc_dep_link_is_up); 296 297 /** 298 * nfc_activate_target - prepare the target for data exchange 299 * 300 * @dev: The nfc device that found the target 301 * @target_idx: index of the target that must be activated 302 * @protocol: nfc protocol that will be used for data exchange 303 */ 304 int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol) 305 { 306 int rc; 307 struct nfc_target *target; 308 309 pr_debug("dev_name=%s target_idx=%u protocol=%u\n", 310 dev_name(&dev->dev), target_idx, protocol); 311 312 device_lock(&dev->dev); 313 314 if (!device_is_registered(&dev->dev)) { 315 rc = -ENODEV; 316 goto error; 317 } 318 319 if (dev->active_target) { 320 rc = -EBUSY; 321 goto error; 322 } 323 324 target = nfc_find_target(dev, target_idx); 325 if (target == NULL) { 326 rc = -ENOTCONN; 327 goto error; 328 } 329 330 rc = dev->ops->activate_target(dev, target, protocol); 331 if (!rc) { 332 dev->active_target = target; 333 dev->rf_mode = NFC_RF_INITIATOR; 334 335 if (dev->ops->check_presence) 336 mod_timer(&dev->check_pres_timer, jiffies + 337 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS)); 338 } 339 340 error: 341 device_unlock(&dev->dev); 342 return rc; 343 } 344 345 /** 346 * nfc_deactivate_target - deactivate a nfc target 347 * 348 * @dev: The nfc device that found the target 349 * @target_idx: index of the target that must be deactivated 350 */ 351 int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx) 352 { 353 int rc = 0; 354 355 pr_debug("dev_name=%s target_idx=%u\n", 356 dev_name(&dev->dev), target_idx); 357 358 device_lock(&dev->dev); 359 360 if (!device_is_registered(&dev->dev)) { 361 rc = -ENODEV; 362 goto error; 363 } 364 365 if (dev->active_target == NULL) { 366 rc = -ENOTCONN; 367 goto error; 368 } 369 370 if (dev->active_target->idx != target_idx) { 371 rc = -ENOTCONN; 372 goto error; 373 } 374 375 if (dev->ops->check_presence) 376 del_timer_sync(&dev->check_pres_timer); 377 378 dev->ops->deactivate_target(dev, dev->active_target); 379 dev->active_target = NULL; 380 381 error: 382 device_unlock(&dev->dev); 383 return rc; 384 } 385 386 /** 387 * nfc_data_exchange - transceive data 388 * 389 * @dev: The nfc device that found the target 390 * @target_idx: index of the target 391 * @skb: data to be sent 392 * @cb: callback called when the response is received 393 * @cb_context: parameter for the callback function 394 * 395 * The user must wait for the callback before calling this function again. 396 */ 397 int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb, 398 data_exchange_cb_t cb, void *cb_context) 399 { 400 int rc; 401 402 pr_debug("dev_name=%s target_idx=%u skb->len=%u\n", 403 dev_name(&dev->dev), target_idx, skb->len); 404 405 device_lock(&dev->dev); 406 407 if (!device_is_registered(&dev->dev)) { 408 rc = -ENODEV; 409 kfree_skb(skb); 410 goto error; 411 } 412 413 if (dev->rf_mode == NFC_RF_INITIATOR && dev->active_target != NULL) { 414 if (dev->active_target->idx != target_idx) { 415 rc = -EADDRNOTAVAIL; 416 kfree_skb(skb); 417 goto error; 418 } 419 420 if (dev->ops->check_presence) 421 del_timer_sync(&dev->check_pres_timer); 422 423 rc = dev->ops->im_transceive(dev, dev->active_target, skb, cb, 424 cb_context); 425 426 if (!rc && dev->ops->check_presence) 427 mod_timer(&dev->check_pres_timer, jiffies + 428 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS)); 429 } else if (dev->rf_mode == NFC_RF_TARGET && dev->ops->tm_send != NULL) { 430 rc = dev->ops->tm_send(dev, skb); 431 } else { 432 rc = -ENOTCONN; 433 kfree_skb(skb); 434 goto error; 435 } 436 437 438 error: 439 device_unlock(&dev->dev); 440 return rc; 441 } 442 443 int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len) 444 { 445 pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len); 446 447 if (gb_len > NFC_MAX_GT_LEN) 448 return -EINVAL; 449 450 return nfc_llcp_set_remote_gb(dev, gb, gb_len); 451 } 452 EXPORT_SYMBOL(nfc_set_remote_general_bytes); 453 454 u8 *nfc_get_local_general_bytes(struct nfc_dev *dev, size_t *gb_len) 455 { 456 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 457 458 return nfc_llcp_general_bytes(dev, gb_len); 459 } 460 EXPORT_SYMBOL(nfc_get_local_general_bytes); 461 462 int nfc_tm_data_received(struct nfc_dev *dev, struct sk_buff *skb) 463 { 464 /* Only LLCP target mode for now */ 465 if (dev->dep_link_up == false) { 466 kfree_skb(skb); 467 return -ENOLINK; 468 } 469 470 return nfc_llcp_data_received(dev, skb); 471 } 472 EXPORT_SYMBOL(nfc_tm_data_received); 473 474 int nfc_tm_activated(struct nfc_dev *dev, u32 protocol, u8 comm_mode, 475 u8 *gb, size_t gb_len) 476 { 477 int rc; 478 479 device_lock(&dev->dev); 480 481 dev->polling = false; 482 483 if (gb != NULL) { 484 rc = nfc_set_remote_general_bytes(dev, gb, gb_len); 485 if (rc < 0) 486 goto out; 487 } 488 489 dev->rf_mode = NFC_RF_TARGET; 490 491 if (protocol == NFC_PROTO_NFC_DEP_MASK) 492 nfc_dep_link_is_up(dev, 0, comm_mode, NFC_RF_TARGET); 493 494 rc = nfc_genl_tm_activated(dev, protocol); 495 496 out: 497 device_unlock(&dev->dev); 498 499 return rc; 500 } 501 EXPORT_SYMBOL(nfc_tm_activated); 502 503 int nfc_tm_deactivated(struct nfc_dev *dev) 504 { 505 dev->dep_link_up = false; 506 507 return nfc_genl_tm_deactivated(dev); 508 } 509 EXPORT_SYMBOL(nfc_tm_deactivated); 510 511 /** 512 * nfc_alloc_send_skb - allocate a skb for data exchange responses 513 * 514 * @size: size to allocate 515 * @gfp: gfp flags 516 */ 517 struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk, 518 unsigned int flags, unsigned int size, 519 unsigned int *err) 520 { 521 struct sk_buff *skb; 522 unsigned int total_size; 523 524 total_size = size + 525 dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE; 526 527 skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err); 528 if (skb) 529 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE); 530 531 return skb; 532 } 533 534 /** 535 * nfc_alloc_recv_skb - allocate a skb for data exchange responses 536 * 537 * @size: size to allocate 538 * @gfp: gfp flags 539 */ 540 struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp) 541 { 542 struct sk_buff *skb; 543 unsigned int total_size; 544 545 total_size = size + 1; 546 skb = alloc_skb(total_size, gfp); 547 548 if (skb) 549 skb_reserve(skb, 1); 550 551 return skb; 552 } 553 EXPORT_SYMBOL(nfc_alloc_recv_skb); 554 555 /** 556 * nfc_targets_found - inform that targets were found 557 * 558 * @dev: The nfc device that found the targets 559 * @targets: array of nfc targets found 560 * @ntargets: targets array size 561 * 562 * The device driver must call this function when one or many nfc targets 563 * are found. After calling this function, the device driver must stop 564 * polling for targets. 565 * NOTE: This function can be called with targets=NULL and n_targets=0 to 566 * notify a driver error, meaning that the polling operation cannot complete. 567 * IMPORTANT: this function must not be called from an atomic context. 568 * In addition, it must also not be called from a context that would prevent 569 * the NFC Core to call other nfc ops entry point concurrently. 570 */ 571 int nfc_targets_found(struct nfc_dev *dev, 572 struct nfc_target *targets, int n_targets) 573 { 574 int i; 575 576 pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets); 577 578 for (i = 0; i < n_targets; i++) 579 targets[i].idx = dev->target_next_idx++; 580 581 device_lock(&dev->dev); 582 583 if (dev->polling == false) { 584 device_unlock(&dev->dev); 585 return 0; 586 } 587 588 dev->polling = false; 589 590 dev->targets_generation++; 591 592 kfree(dev->targets); 593 dev->targets = NULL; 594 595 if (targets) { 596 dev->targets = kmemdup(targets, 597 n_targets * sizeof(struct nfc_target), 598 GFP_ATOMIC); 599 600 if (!dev->targets) { 601 dev->n_targets = 0; 602 device_unlock(&dev->dev); 603 return -ENOMEM; 604 } 605 } 606 607 dev->n_targets = n_targets; 608 device_unlock(&dev->dev); 609 610 nfc_genl_targets_found(dev); 611 612 return 0; 613 } 614 EXPORT_SYMBOL(nfc_targets_found); 615 616 /** 617 * nfc_target_lost - inform that an activated target went out of field 618 * 619 * @dev: The nfc device that had the activated target in field 620 * @target_idx: the nfc index of the target 621 * 622 * The device driver must call this function when the activated target 623 * goes out of the field. 624 * IMPORTANT: this function must not be called from an atomic context. 625 * In addition, it must also not be called from a context that would prevent 626 * the NFC Core to call other nfc ops entry point concurrently. 627 */ 628 int nfc_target_lost(struct nfc_dev *dev, u32 target_idx) 629 { 630 struct nfc_target *tg; 631 int i; 632 633 pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx); 634 635 device_lock(&dev->dev); 636 637 for (i = 0; i < dev->n_targets; i++) { 638 tg = &dev->targets[i]; 639 if (tg->idx == target_idx) 640 break; 641 } 642 643 if (i == dev->n_targets) { 644 device_unlock(&dev->dev); 645 return -EINVAL; 646 } 647 648 dev->targets_generation++; 649 dev->n_targets--; 650 dev->active_target = NULL; 651 652 if (dev->n_targets) { 653 memcpy(&dev->targets[i], &dev->targets[i + 1], 654 (dev->n_targets - i) * sizeof(struct nfc_target)); 655 } else { 656 kfree(dev->targets); 657 dev->targets = NULL; 658 } 659 660 device_unlock(&dev->dev); 661 662 nfc_genl_target_lost(dev, target_idx); 663 664 return 0; 665 } 666 EXPORT_SYMBOL(nfc_target_lost); 667 668 inline void nfc_driver_failure(struct nfc_dev *dev, int err) 669 { 670 nfc_targets_found(dev, NULL, 0); 671 } 672 EXPORT_SYMBOL(nfc_driver_failure); 673 674 static void nfc_release(struct device *d) 675 { 676 struct nfc_dev *dev = to_nfc_dev(d); 677 678 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 679 680 if (dev->ops->check_presence) { 681 del_timer_sync(&dev->check_pres_timer); 682 destroy_workqueue(dev->check_pres_wq); 683 } 684 685 nfc_genl_data_exit(&dev->genl_data); 686 kfree(dev->targets); 687 kfree(dev); 688 } 689 690 static void nfc_check_pres_work(struct work_struct *work) 691 { 692 struct nfc_dev *dev = container_of(work, struct nfc_dev, 693 check_pres_work); 694 int rc; 695 696 device_lock(&dev->dev); 697 698 if (dev->active_target && timer_pending(&dev->check_pres_timer) == 0) { 699 rc = dev->ops->check_presence(dev, dev->active_target); 700 if (!rc) { 701 mod_timer(&dev->check_pres_timer, jiffies + 702 msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS)); 703 } else { 704 u32 active_target_idx = dev->active_target->idx; 705 device_unlock(&dev->dev); 706 nfc_target_lost(dev, active_target_idx); 707 return; 708 } 709 } 710 711 device_unlock(&dev->dev); 712 } 713 714 static void nfc_check_pres_timeout(unsigned long data) 715 { 716 struct nfc_dev *dev = (struct nfc_dev *)data; 717 718 queue_work(dev->check_pres_wq, &dev->check_pres_work); 719 } 720 721 struct class nfc_class = { 722 .name = "nfc", 723 .dev_release = nfc_release, 724 }; 725 EXPORT_SYMBOL(nfc_class); 726 727 static int match_idx(struct device *d, void *data) 728 { 729 struct nfc_dev *dev = to_nfc_dev(d); 730 unsigned int *idx = data; 731 732 return dev->idx == *idx; 733 } 734 735 struct nfc_dev *nfc_get_device(unsigned int idx) 736 { 737 struct device *d; 738 739 d = class_find_device(&nfc_class, NULL, &idx, match_idx); 740 if (!d) 741 return NULL; 742 743 return to_nfc_dev(d); 744 } 745 746 /** 747 * nfc_allocate_device - allocate a new nfc device 748 * 749 * @ops: device operations 750 * @supported_protocols: NFC protocols supported by the device 751 */ 752 struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops, 753 u32 supported_protocols, 754 int tx_headroom, int tx_tailroom) 755 { 756 static atomic_t dev_no = ATOMIC_INIT(0); 757 struct nfc_dev *dev; 758 759 if (!ops->start_poll || !ops->stop_poll || !ops->activate_target || 760 !ops->deactivate_target || !ops->im_transceive) 761 return NULL; 762 763 if (!supported_protocols) 764 return NULL; 765 766 dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL); 767 if (!dev) 768 return NULL; 769 770 dev->dev.class = &nfc_class; 771 dev->idx = atomic_inc_return(&dev_no) - 1; 772 dev_set_name(&dev->dev, "nfc%d", dev->idx); 773 device_initialize(&dev->dev); 774 775 dev->ops = ops; 776 dev->supported_protocols = supported_protocols; 777 dev->tx_headroom = tx_headroom; 778 dev->tx_tailroom = tx_tailroom; 779 780 nfc_genl_data_init(&dev->genl_data); 781 782 783 /* first generation must not be 0 */ 784 dev->targets_generation = 1; 785 786 if (ops->check_presence) { 787 char name[32]; 788 init_timer(&dev->check_pres_timer); 789 dev->check_pres_timer.data = (unsigned long)dev; 790 dev->check_pres_timer.function = nfc_check_pres_timeout; 791 792 INIT_WORK(&dev->check_pres_work, nfc_check_pres_work); 793 snprintf(name, sizeof(name), "nfc%d_check_pres_wq", dev->idx); 794 dev->check_pres_wq = alloc_workqueue(name, WQ_NON_REENTRANT | 795 WQ_UNBOUND | 796 WQ_MEM_RECLAIM, 1); 797 if (dev->check_pres_wq == NULL) { 798 kfree(dev); 799 return NULL; 800 } 801 } 802 803 return dev; 804 } 805 EXPORT_SYMBOL(nfc_allocate_device); 806 807 /** 808 * nfc_register_device - register a nfc device in the nfc subsystem 809 * 810 * @dev: The nfc device to register 811 */ 812 int nfc_register_device(struct nfc_dev *dev) 813 { 814 int rc; 815 816 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 817 818 mutex_lock(&nfc_devlist_mutex); 819 nfc_devlist_generation++; 820 rc = device_add(&dev->dev); 821 mutex_unlock(&nfc_devlist_mutex); 822 823 if (rc < 0) 824 return rc; 825 826 rc = nfc_llcp_register_device(dev); 827 if (rc) 828 pr_err("Could not register llcp device\n"); 829 830 rc = nfc_genl_device_added(dev); 831 if (rc) 832 pr_debug("The userspace won't be notified that the device %s was added\n", 833 dev_name(&dev->dev)); 834 835 return 0; 836 } 837 EXPORT_SYMBOL(nfc_register_device); 838 839 /** 840 * nfc_unregister_device - unregister a nfc device in the nfc subsystem 841 * 842 * @dev: The nfc device to unregister 843 */ 844 void nfc_unregister_device(struct nfc_dev *dev) 845 { 846 int rc; 847 848 pr_debug("dev_name=%s\n", dev_name(&dev->dev)); 849 850 mutex_lock(&nfc_devlist_mutex); 851 nfc_devlist_generation++; 852 853 /* lock to avoid unregistering a device while an operation 854 is in progress */ 855 device_lock(&dev->dev); 856 device_del(&dev->dev); 857 device_unlock(&dev->dev); 858 859 mutex_unlock(&nfc_devlist_mutex); 860 861 nfc_llcp_unregister_device(dev); 862 863 rc = nfc_genl_device_removed(dev); 864 if (rc) 865 pr_debug("The userspace won't be notified that the device %s was removed\n", 866 dev_name(&dev->dev)); 867 868 } 869 EXPORT_SYMBOL(nfc_unregister_device); 870 871 static int __init nfc_init(void) 872 { 873 int rc; 874 875 pr_info("NFC Core ver %s\n", VERSION); 876 877 rc = class_register(&nfc_class); 878 if (rc) 879 return rc; 880 881 rc = nfc_genl_init(); 882 if (rc) 883 goto err_genl; 884 885 /* the first generation must not be 0 */ 886 nfc_devlist_generation = 1; 887 888 rc = rawsock_init(); 889 if (rc) 890 goto err_rawsock; 891 892 rc = nfc_llcp_init(); 893 if (rc) 894 goto err_llcp_sock; 895 896 rc = af_nfc_init(); 897 if (rc) 898 goto err_af_nfc; 899 900 return 0; 901 902 err_af_nfc: 903 nfc_llcp_exit(); 904 err_llcp_sock: 905 rawsock_exit(); 906 err_rawsock: 907 nfc_genl_exit(); 908 err_genl: 909 class_unregister(&nfc_class); 910 return rc; 911 } 912 913 static void __exit nfc_exit(void) 914 { 915 af_nfc_exit(); 916 nfc_llcp_exit(); 917 rawsock_exit(); 918 nfc_genl_exit(); 919 class_unregister(&nfc_class); 920 } 921 922 subsys_initcall(nfc_init); 923 module_exit(nfc_exit); 924 925 MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>"); 926 MODULE_DESCRIPTION("NFC Core ver " VERSION); 927 MODULE_VERSION(VERSION); 928 MODULE_LICENSE("GPL"); 929 MODULE_ALIAS_NETPROTO(PF_NFC); 930 MODULE_ALIAS_GENL_FAMILY(NFC_GENL_NAME); 931