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/rfkill.h>
  31 #include <linux/nfc.h>
  32
  33 #include <net/genetlink.h>
  34
  35 #include "nfc.h"
  36
  37 #define VERSION "0.1"
  38
  39 #define NFC_CHECK_PRES_FREQ_MS  2000
  40
  41 int nfc_devlist_generation;
  42 DEFINE_MUTEX(nfc_devlist_mutex);
  43
  44 /* NFC device ID bitmap */
  45 static DEFINE_IDA(nfc_index_ida);
  46
  47 int nfc_fw_download(struct nfc_dev *dev, const char *firmware_name)
  48 {
  49         int rc = 0;
  50
  51         pr_debug("%s do firmware %s\n", dev_name(&dev->dev), firmware_name);
  52
  53         device_lock(&dev->dev);
  54
  55         if (!device_is_registered(&dev->dev)) {
  56                 rc = -ENODEV;
  57                 goto error;
  58         }
  59
  60         if (dev->dev_up) {
  61                 rc = -EBUSY;
  62                 goto error;
  63         }
  64
  65         if (!dev->ops->fw_download) {
  66                 rc = -EOPNOTSUPP;
  67                 goto error;
  68         }
  69
  70         dev->fw_download_in_progress = true;
  71         rc = dev->ops->fw_download(dev, firmware_name);
  72         if (rc)
  73                 dev->fw_download_in_progress = false;
  74
  75 error:
  76         device_unlock(&dev->dev);
  77         return rc;
  78 }
  79
  80 /**
  81  * nfc_fw_download_done - inform that a firmware download was completed
  82  *
  83  * @dev: The nfc device to which firmware was downloaded
  84  * @firmware_name: The firmware filename
  85  * @result: The positive value of a standard errno value
  86  */
  87 int nfc_fw_download_done(struct nfc_dev *dev, const char *firmware_name,
  88                          u32 result)
  89 {
  90         dev->fw_download_in_progress = false;
  91
  92         return nfc_genl_fw_download_done(dev, firmware_name, result);
  93 }
  94 EXPORT_SYMBOL(nfc_fw_download_done);
  95
  96 /**
  97  * nfc_dev_up - turn on the NFC device
  98  *
  99  * @dev: The nfc device to be turned on
 100  *
 101  * The device remains up until the nfc_dev_down function is called.
 102  */
 103 int nfc_dev_up(struct nfc_dev *dev)
 104 {
 105         int rc = 0;
 106
 107         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 108
 109         device_lock(&dev->dev);
 110
 111         if (dev->rfkill && rfkill_blocked(dev->rfkill)) {
 112                 rc = -ERFKILL;
 113                 goto error;
 114         }
 115
 116         if (!device_is_registered(&dev->dev)) {
 117                 rc = -ENODEV;
 118                 goto error;
 119         }
 120
 121         if (dev->fw_download_in_progress) {
 122                 rc = -EBUSY;
 123                 goto error;
 124         }
 125
 126         if (dev->dev_up) {
 127                 rc = -EALREADY;
 128                 goto error;
 129         }
 130
 131         if (dev->ops->dev_up)
 132                 rc = dev->ops->dev_up(dev);
 133
 134         if (!rc)
 135                 dev->dev_up = true;
 136
 137         /* We have to enable the device before discovering SEs */
 138         if (dev->ops->discover_se) {
 139                 rc = dev->ops->discover_se(dev);
 140                 if (rc)
 141                         pr_warn("SE discovery failed\n");
 142         }
 143
 144 error:
 145         device_unlock(&dev->dev);
 146         return rc;
 147 }
 148
 149 /**
 150  * nfc_dev_down - turn off the NFC device
 151  *
 152  * @dev: The nfc device to be turned off
 153  */
 154 int nfc_dev_down(struct nfc_dev *dev)
 155 {
 156         int rc = 0;
 157
 158         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 159
 160         device_lock(&dev->dev);
 161
 162         if (!device_is_registered(&dev->dev)) {
 163                 rc = -ENODEV;
 164                 goto error;
 165         }
 166
 167         if (!dev->dev_up) {
 168                 rc = -EALREADY;
 169                 goto error;
 170         }
 171
 172         if (dev->polling || dev->active_target) {
 173                 rc = -EBUSY;
 174                 goto error;
 175         }
 176
 177         if (dev->ops->dev_down)
 178                 dev->ops->dev_down(dev);
 179
 180         dev->dev_up = false;
 181
 182 error:
 183         device_unlock(&dev->dev);
 184         return rc;
 185 }
 186
 187 static int nfc_rfkill_set_block(void *data, bool blocked)
 188 {
 189         struct nfc_dev *dev = data;
 190
 191         pr_debug("%s blocked %d", dev_name(&dev->dev), blocked);
 192
 193         if (!blocked)
 194                 return 0;
 195
 196         nfc_dev_down(dev);
 197
 198         return 0;
 199 }
 200
 201 static const struct rfkill_ops nfc_rfkill_ops = {
 202         .set_block = nfc_rfkill_set_block,
 203 };
 204
 205 /**
 206  * nfc_start_poll - start polling for nfc targets
 207  *
 208  * @dev: The nfc device that must start polling
 209  * @protocols: bitset of nfc protocols that must be used for polling
 210  *
 211  * The device remains polling for targets until a target is found or
 212  * the nfc_stop_poll function is called.
 213  */
 214 int nfc_start_poll(struct nfc_dev *dev, u32 im_protocols, u32 tm_protocols)
 215 {
 216         int rc;
 217
 218         pr_debug("dev_name %s initiator protocols 0x%x target protocols 0x%x\n",
 219                  dev_name(&dev->dev), im_protocols, tm_protocols);
 220
 221         if (!im_protocols && !tm_protocols)
 222                 return -EINVAL;
 223
 224         device_lock(&dev->dev);
 225
 226         if (!device_is_registered(&dev->dev)) {
 227                 rc = -ENODEV;
 228                 goto error;
 229         }
 230
 231         if (!dev->dev_up) {
 232                 rc = -ENODEV;
 233                 goto error;
 234         }
 235
 236         if (dev->polling) {
 237                 rc = -EBUSY;
 238                 goto error;
 239         }
 240
 241         rc = dev->ops->start_poll(dev, im_protocols, tm_protocols);
 242         if (!rc) {
 243                 dev->polling = true;
 244                 dev->rf_mode = NFC_RF_NONE;
 245         }
 246
 247 error:
 248         device_unlock(&dev->dev);
 249         return rc;
 250 }
 251
 252 /**
 253  * nfc_stop_poll - stop polling for nfc targets
 254  *
 255  * @dev: The nfc device that must stop polling
 256  */
 257 int nfc_stop_poll(struct nfc_dev *dev)
 258 {
 259         int rc = 0;
 260
 261         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 262
 263         device_lock(&dev->dev);
 264
 265         if (!device_is_registered(&dev->dev)) {
 266                 rc = -ENODEV;
 267                 goto error;
 268         }
 269
 270         if (!dev->polling) {
 271                 rc = -EINVAL;
 272                 goto error;
 273         }
 274
 275         dev->ops->stop_poll(dev);
 276         dev->polling = false;
 277         dev->rf_mode = NFC_RF_NONE;
 278
 279 error:
 280         device_unlock(&dev->dev);
 281         return rc;
 282 }
 283
 284 static struct nfc_target *nfc_find_target(struct nfc_dev *dev, u32 target_idx)
 285 {
 286         int i;
 287
 288         if (dev->n_targets == 0)
 289                 return NULL;
 290
 291         for (i = 0; i < dev->n_targets; i++) {
 292                 if (dev->targets[i].idx == target_idx)
 293                         return &dev->targets[i];
 294         }
 295
 296         return NULL;
 297 }
 298
 299 int nfc_dep_link_up(struct nfc_dev *dev, int target_index, u8 comm_mode)
 300 {
 301         int rc = 0;
 302         u8 *gb;
 303         size_t gb_len;
 304         struct nfc_target *target;
 305
 306         pr_debug("dev_name=%s comm %d\n", dev_name(&dev->dev), comm_mode);
 307
 308         if (!dev->ops->dep_link_up)
 309                 return -EOPNOTSUPP;
 310
 311         device_lock(&dev->dev);
 312
 313         if (!device_is_registered(&dev->dev)) {
 314                 rc = -ENODEV;
 315                 goto error;
 316         }
 317
 318         if (dev->dep_link_up == true) {
 319                 rc = -EALREADY;
 320                 goto error;
 321         }
 322
 323         gb = nfc_llcp_general_bytes(dev, &gb_len);
 324         if (gb_len > NFC_MAX_GT_LEN) {
 325                 rc = -EINVAL;
 326                 goto error;
 327         }
 328
 329         target = nfc_find_target(dev, target_index);
 330         if (target == NULL) {
 331                 rc = -ENOTCONN;
 332                 goto error;
 333         }
 334
 335         rc = dev->ops->dep_link_up(dev, target, comm_mode, gb, gb_len);
 336         if (!rc) {
 337                 dev->active_target = target;
 338                 dev->rf_mode = NFC_RF_INITIATOR;
 339         }
 340
 341 error:
 342         device_unlock(&dev->dev);
 343         return rc;
 344 }
 345
 346 int nfc_dep_link_down(struct nfc_dev *dev)
 347 {
 348         int rc = 0;
 349
 350         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 351
 352         if (!dev->ops->dep_link_down)
 353                 return -EOPNOTSUPP;
 354
 355         device_lock(&dev->dev);
 356
 357         if (!device_is_registered(&dev->dev)) {
 358                 rc = -ENODEV;
 359                 goto error;
 360         }
 361
 362         if (dev->dep_link_up == false) {
 363                 rc = -EALREADY;
 364                 goto error;
 365         }
 366
 367         rc = dev->ops->dep_link_down(dev);
 368         if (!rc) {
 369                 dev->dep_link_up = false;
 370                 dev->active_target = NULL;
 371                 dev->rf_mode = NFC_RF_NONE;
 372                 nfc_llcp_mac_is_down(dev);
 373                 nfc_genl_dep_link_down_event(dev);
 374         }
 375
 376 error:
 377         device_unlock(&dev->dev);
 378
 379         return rc;
 380 }
 381
 382 int nfc_dep_link_is_up(struct nfc_dev *dev, u32 target_idx,
 383                        u8 comm_mode, u8 rf_mode)
 384 {
 385         dev->dep_link_up = true;
 386
 387         nfc_llcp_mac_is_up(dev, target_idx, comm_mode, rf_mode);
 388
 389         return nfc_genl_dep_link_up_event(dev, target_idx, comm_mode, rf_mode);
 390 }
 391 EXPORT_SYMBOL(nfc_dep_link_is_up);
 392
 393 /**
 394  * nfc_activate_target - prepare the target for data exchange
 395  *
 396  * @dev: The nfc device that found the target
 397  * @target_idx: index of the target that must be activated
 398  * @protocol: nfc protocol that will be used for data exchange
 399  */
 400 int nfc_activate_target(struct nfc_dev *dev, u32 target_idx, u32 protocol)
 401 {
 402         int rc;
 403         struct nfc_target *target;
 404
 405         pr_debug("dev_name=%s target_idx=%u protocol=%u\n",
 406                  dev_name(&dev->dev), target_idx, protocol);
 407
 408         device_lock(&dev->dev);
 409
 410         if (!device_is_registered(&dev->dev)) {
 411                 rc = -ENODEV;
 412                 goto error;
 413         }
 414
 415         if (dev->active_target) {
 416                 rc = -EBUSY;
 417                 goto error;
 418         }
 419
 420         target = nfc_find_target(dev, target_idx);
 421         if (target == NULL) {
 422                 rc = -ENOTCONN;
 423                 goto error;
 424         }
 425
 426         rc = dev->ops->activate_target(dev, target, protocol);
 427         if (!rc) {
 428                 dev->active_target = target;
 429                 dev->rf_mode = NFC_RF_INITIATOR;
 430
 431                 if (dev->ops->check_presence && !dev->shutting_down)
 432                         mod_timer(&dev->check_pres_timer, jiffies +
 433                                   msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
 434         }
 435
 436 error:
 437         device_unlock(&dev->dev);
 438         return rc;
 439 }
 440
 441 /**
 442  * nfc_deactivate_target - deactivate a nfc target
 443  *
 444  * @dev: The nfc device that found the target
 445  * @target_idx: index of the target that must be deactivated
 446  */
 447 int nfc_deactivate_target(struct nfc_dev *dev, u32 target_idx)
 448 {
 449         int rc = 0;
 450
 451         pr_debug("dev_name=%s target_idx=%u\n",
 452                  dev_name(&dev->dev), target_idx);
 453
 454         device_lock(&dev->dev);
 455
 456         if (!device_is_registered(&dev->dev)) {
 457                 rc = -ENODEV;
 458                 goto error;
 459         }
 460
 461         if (dev->active_target == NULL) {
 462                 rc = -ENOTCONN;
 463                 goto error;
 464         }
 465
 466         if (dev->active_target->idx != target_idx) {
 467                 rc = -ENOTCONN;
 468                 goto error;
 469         }
 470
 471         if (dev->ops->check_presence)
 472                 del_timer_sync(&dev->check_pres_timer);
 473
 474         dev->ops->deactivate_target(dev, dev->active_target);
 475         dev->active_target = NULL;
 476
 477 error:
 478         device_unlock(&dev->dev);
 479         return rc;
 480 }
 481
 482 /**
 483  * nfc_data_exchange - transceive data
 484  *
 485  * @dev: The nfc device that found the target
 486  * @target_idx: index of the target
 487  * @skb: data to be sent
 488  * @cb: callback called when the response is received
 489  * @cb_context: parameter for the callback function
 490  *
 491  * The user must wait for the callback before calling this function again.
 492  */
 493 int nfc_data_exchange(struct nfc_dev *dev, u32 target_idx, struct sk_buff *skb,
 494                       data_exchange_cb_t cb, void *cb_context)
 495 {
 496         int rc;
 497
 498         pr_debug("dev_name=%s target_idx=%u skb->len=%u\n",
 499                  dev_name(&dev->dev), target_idx, skb->len);
 500
 501         device_lock(&dev->dev);
 502
 503         if (!device_is_registered(&dev->dev)) {
 504                 rc = -ENODEV;
 505                 kfree_skb(skb);
 506                 goto error;
 507         }
 508
 509         if (dev->rf_mode == NFC_RF_INITIATOR && dev->active_target != NULL) {
 510                 if (dev->active_target->idx != target_idx) {
 511                         rc = -EADDRNOTAVAIL;
 512                         kfree_skb(skb);
 513                         goto error;
 514                 }
 515
 516                 if (dev->ops->check_presence)
 517                         del_timer_sync(&dev->check_pres_timer);
 518
 519                 rc = dev->ops->im_transceive(dev, dev->active_target, skb, cb,
 520                                              cb_context);
 521
 522                 if (!rc && dev->ops->check_presence && !dev->shutting_down)
 523                         mod_timer(&dev->check_pres_timer, jiffies +
 524                                   msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
 525         } else if (dev->rf_mode == NFC_RF_TARGET && dev->ops->tm_send != NULL) {
 526                 rc = dev->ops->tm_send(dev, skb);
 527         } else {
 528                 rc = -ENOTCONN;
 529                 kfree_skb(skb);
 530                 goto error;
 531         }
 532
 533
 534 error:
 535         device_unlock(&dev->dev);
 536         return rc;
 537 }
 538
 539 static struct nfc_se *find_se(struct nfc_dev *dev, u32 se_idx)
 540 {
 541         struct nfc_se *se, *n;
 542
 543         list_for_each_entry_safe(se, n, &dev->secure_elements, list)
 544                 if (se->idx == se_idx)
 545                         return se;
 546
 547         return NULL;
 548 }
 549
 550 int nfc_enable_se(struct nfc_dev *dev, u32 se_idx)
 551 {
 552
 553         struct nfc_se *se;
 554         int rc;
 555
 556         pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
 557
 558         device_lock(&dev->dev);
 559
 560         if (!device_is_registered(&dev->dev)) {
 561                 rc = -ENODEV;
 562                 goto error;
 563         }
 564
 565         if (!dev->dev_up) {
 566                 rc = -ENODEV;
 567                 goto error;
 568         }
 569
 570         if (dev->polling) {
 571                 rc = -EBUSY;
 572                 goto error;
 573         }
 574
 575         if (!dev->ops->enable_se || !dev->ops->disable_se) {
 576                 rc = -EOPNOTSUPP;
 577                 goto error;
 578         }
 579
 580         se = find_se(dev, se_idx);
 581         if (!se) {
 582                 rc = -EINVAL;
 583                 goto error;
 584         }
 585
 586         if (se->state == NFC_SE_ENABLED) {
 587                 rc = -EALREADY;
 588                 goto error;
 589         }
 590
 591         rc = dev->ops->enable_se(dev, se_idx);
 592         if (rc >= 0)
 593                 se->state = NFC_SE_ENABLED;
 594
 595 error:
 596         device_unlock(&dev->dev);
 597         return rc;
 598 }
 599
 600 int nfc_disable_se(struct nfc_dev *dev, u32 se_idx)
 601 {
 602
 603         struct nfc_se *se;
 604         int rc;
 605
 606         pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
 607
 608         device_lock(&dev->dev);
 609
 610         if (!device_is_registered(&dev->dev)) {
 611                 rc = -ENODEV;
 612                 goto error;
 613         }
 614
 615         if (!dev->dev_up) {
 616                 rc = -ENODEV;
 617                 goto error;
 618         }
 619
 620         if (!dev->ops->enable_se || !dev->ops->disable_se) {
 621                 rc = -EOPNOTSUPP;
 622                 goto error;
 623         }
 624
 625         se = find_se(dev, se_idx);
 626         if (!se) {
 627                 rc = -EINVAL;
 628                 goto error;
 629         }
 630
 631         if (se->state == NFC_SE_DISABLED) {
 632                 rc = -EALREADY;
 633                 goto error;
 634         }
 635
 636         rc = dev->ops->disable_se(dev, se_idx);
 637         if (rc >= 0)
 638                 se->state = NFC_SE_DISABLED;
 639
 640 error:
 641         device_unlock(&dev->dev);
 642         return rc;
 643 }
 644
 645 int nfc_set_remote_general_bytes(struct nfc_dev *dev, u8 *gb, u8 gb_len)
 646 {
 647         pr_debug("dev_name=%s gb_len=%d\n", dev_name(&dev->dev), gb_len);
 648
 649         if (gb_len > NFC_MAX_GT_LEN)
 650                 return -EINVAL;
 651
 652         return nfc_llcp_set_remote_gb(dev, gb, gb_len);
 653 }
 654 EXPORT_SYMBOL(nfc_set_remote_general_bytes);
 655
 656 u8 *nfc_get_local_general_bytes(struct nfc_dev *dev, size_t *gb_len)
 657 {
 658         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 659
 660         return nfc_llcp_general_bytes(dev, gb_len);
 661 }
 662 EXPORT_SYMBOL(nfc_get_local_general_bytes);
 663
 664 int nfc_tm_data_received(struct nfc_dev *dev, struct sk_buff *skb)
 665 {
 666         /* Only LLCP target mode for now */
 667         if (dev->dep_link_up == false) {
 668                 kfree_skb(skb);
 669                 return -ENOLINK;
 670         }
 671
 672         return nfc_llcp_data_received(dev, skb);
 673 }
 674 EXPORT_SYMBOL(nfc_tm_data_received);
 675
 676 int nfc_tm_activated(struct nfc_dev *dev, u32 protocol, u8 comm_mode,
 677                      u8 *gb, size_t gb_len)
 678 {
 679         int rc;
 680
 681         device_lock(&dev->dev);
 682
 683         dev->polling = false;
 684
 685         if (gb != NULL) {
 686                 rc = nfc_set_remote_general_bytes(dev, gb, gb_len);
 687                 if (rc < 0)
 688                         goto out;
 689         }
 690
 691         dev->rf_mode = NFC_RF_TARGET;
 692
 693         if (protocol == NFC_PROTO_NFC_DEP_MASK)
 694                 nfc_dep_link_is_up(dev, 0, comm_mode, NFC_RF_TARGET);
 695
 696         rc = nfc_genl_tm_activated(dev, protocol);
 697
 698 out:
 699         device_unlock(&dev->dev);
 700
 701         return rc;
 702 }
 703 EXPORT_SYMBOL(nfc_tm_activated);
 704
 705 int nfc_tm_deactivated(struct nfc_dev *dev)
 706 {
 707         dev->dep_link_up = false;
 708         dev->rf_mode = NFC_RF_NONE;
 709
 710         return nfc_genl_tm_deactivated(dev);
 711 }
 712 EXPORT_SYMBOL(nfc_tm_deactivated);
 713
 714 /**
 715  * nfc_alloc_send_skb - allocate a skb for data exchange responses
 716  *
 717  * @size: size to allocate
 718  * @gfp: gfp flags
 719  */
 720 struct sk_buff *nfc_alloc_send_skb(struct nfc_dev *dev, struct sock *sk,
 721                                    unsigned int flags, unsigned int size,
 722                                    unsigned int *err)
 723 {
 724         struct sk_buff *skb;
 725         unsigned int total_size;
 726
 727         total_size = size +
 728                 dev->tx_headroom + dev->tx_tailroom + NFC_HEADER_SIZE;
 729
 730         skb = sock_alloc_send_skb(sk, total_size, flags & MSG_DONTWAIT, err);
 731         if (skb)
 732                 skb_reserve(skb, dev->tx_headroom + NFC_HEADER_SIZE);
 733
 734         return skb;
 735 }
 736
 737 /**
 738  * nfc_alloc_recv_skb - allocate a skb for data exchange responses
 739  *
 740  * @size: size to allocate
 741  * @gfp: gfp flags
 742  */
 743 struct sk_buff *nfc_alloc_recv_skb(unsigned int size, gfp_t gfp)
 744 {
 745         struct sk_buff *skb;
 746         unsigned int total_size;
 747
 748         total_size = size + 1;
 749         skb = alloc_skb(total_size, gfp);
 750
 751         if (skb)
 752                 skb_reserve(skb, 1);
 753
 754         return skb;
 755 }
 756 EXPORT_SYMBOL(nfc_alloc_recv_skb);
 757
 758 /**
 759  * nfc_targets_found - inform that targets were found
 760  *
 761  * @dev: The nfc device that found the targets
 762  * @targets: array of nfc targets found
 763  * @ntargets: targets array size
 764  *
 765  * The device driver must call this function when one or many nfc targets
 766  * are found. After calling this function, the device driver must stop
 767  * polling for targets.
 768  * NOTE: This function can be called with targets=NULL and n_targets=0 to
 769  * notify a driver error, meaning that the polling operation cannot complete.
 770  * IMPORTANT: this function must not be called from an atomic context.
 771  * In addition, it must also not be called from a context that would prevent
 772  * the NFC Core to call other nfc ops entry point concurrently.
 773  */
 774 int nfc_targets_found(struct nfc_dev *dev,
 775                       struct nfc_target *targets, int n_targets)
 776 {
 777         int i;
 778
 779         pr_debug("dev_name=%s n_targets=%d\n", dev_name(&dev->dev), n_targets);
 780
 781         for (i = 0; i < n_targets; i++)
 782                 targets[i].idx = dev->target_next_idx++;
 783
 784         device_lock(&dev->dev);
 785
 786         if (dev->polling == false) {
 787                 device_unlock(&dev->dev);
 788                 return 0;
 789         }
 790
 791         dev->polling = false;
 792
 793         dev->targets_generation++;
 794
 795         kfree(dev->targets);
 796         dev->targets = NULL;
 797
 798         if (targets) {
 799                 dev->targets = kmemdup(targets,
 800                                        n_targets * sizeof(struct nfc_target),
 801                                        GFP_ATOMIC);
 802
 803                 if (!dev->targets) {
 804                         dev->n_targets = 0;
 805                         device_unlock(&dev->dev);
 806                         return -ENOMEM;
 807                 }
 808         }
 809
 810         dev->n_targets = n_targets;
 811         device_unlock(&dev->dev);
 812
 813         nfc_genl_targets_found(dev);
 814
 815         return 0;
 816 }
 817 EXPORT_SYMBOL(nfc_targets_found);
 818
 819 /**
 820  * nfc_target_lost - inform that an activated target went out of field
 821  *
 822  * @dev: The nfc device that had the activated target in field
 823  * @target_idx: the nfc index of the target
 824  *
 825  * The device driver must call this function when the activated target
 826  * goes out of the field.
 827  * IMPORTANT: this function must not be called from an atomic context.
 828  * In addition, it must also not be called from a context that would prevent
 829  * the NFC Core to call other nfc ops entry point concurrently.
 830  */
 831 int nfc_target_lost(struct nfc_dev *dev, u32 target_idx)
 832 {
 833         struct nfc_target *tg;
 834         int i;
 835
 836         pr_debug("dev_name %s n_target %d\n", dev_name(&dev->dev), target_idx);
 837
 838         device_lock(&dev->dev);
 839
 840         for (i = 0; i < dev->n_targets; i++) {
 841                 tg = &dev->targets[i];
 842                 if (tg->idx == target_idx)
 843                         break;
 844         }
 845
 846         if (i == dev->n_targets) {
 847                 device_unlock(&dev->dev);
 848                 return -EINVAL;
 849         }
 850
 851         dev->targets_generation++;
 852         dev->n_targets--;
 853         dev->active_target = NULL;
 854
 855         if (dev->n_targets) {
 856                 memcpy(&dev->targets[i], &dev->targets[i + 1],
 857                        (dev->n_targets - i) * sizeof(struct nfc_target));
 858         } else {
 859                 kfree(dev->targets);
 860                 dev->targets = NULL;
 861         }
 862
 863         device_unlock(&dev->dev);
 864
 865         nfc_genl_target_lost(dev, target_idx);
 866
 867         return 0;
 868 }
 869 EXPORT_SYMBOL(nfc_target_lost);
 870
 871 inline void nfc_driver_failure(struct nfc_dev *dev, int err)
 872 {
 873         nfc_targets_found(dev, NULL, 0);
 874 }
 875 EXPORT_SYMBOL(nfc_driver_failure);
 876
 877 int nfc_add_se(struct nfc_dev *dev, u32 se_idx, u16 type)
 878 {
 879         struct nfc_se *se;
 880         int rc;
 881
 882         pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
 883
 884         se = find_se(dev, se_idx);
 885         if (se)
 886                 return -EALREADY;
 887
 888         se = kzalloc(sizeof(struct nfc_se), GFP_KERNEL);
 889         if (!se)
 890                 return -ENOMEM;
 891
 892         se->idx = se_idx;
 893         se->type = type;
 894         se->state = NFC_SE_DISABLED;
 895         INIT_LIST_HEAD(&se->list);
 896
 897         list_add(&se->list, &dev->secure_elements);
 898
 899         rc = nfc_genl_se_added(dev, se_idx, type);
 900         if (rc < 0) {
 901                 list_del(&se->list);
 902                 kfree(se);
 903
 904                 return rc;
 905         }
 906
 907         return 0;
 908 }
 909 EXPORT_SYMBOL(nfc_add_se);
 910
 911 int nfc_remove_se(struct nfc_dev *dev, u32 se_idx)
 912 {
 913         struct nfc_se *se, *n;
 914         int rc;
 915
 916         pr_debug("%s se index %d\n", dev_name(&dev->dev), se_idx);
 917
 918         list_for_each_entry_safe(se, n, &dev->secure_elements, list)
 919                 if (se->idx == se_idx) {
 920                         rc = nfc_genl_se_removed(dev, se_idx);
 921                         if (rc < 0)
 922                                 return rc;
 923
 924                         list_del(&se->list);
 925                         kfree(se);
 926
 927                         return 0;
 928                 }
 929
 930         return -EINVAL;
 931 }
 932 EXPORT_SYMBOL(nfc_remove_se);
 933
 934 static void nfc_release(struct device *d)
 935 {
 936         struct nfc_dev *dev = to_nfc_dev(d);
 937         struct nfc_se *se, *n;
 938
 939         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
 940
 941         nfc_genl_data_exit(&dev->genl_data);
 942         kfree(dev->targets);
 943
 944         list_for_each_entry_safe(se, n, &dev->secure_elements, list) {
 945                         nfc_genl_se_removed(dev, se->idx);
 946                         list_del(&se->list);
 947                         kfree(se);
 948         }
 949
 950         kfree(dev);
 951 }
 952
 953 static void nfc_check_pres_work(struct work_struct *work)
 954 {
 955         struct nfc_dev *dev = container_of(work, struct nfc_dev,
 956                                            check_pres_work);
 957         int rc;
 958
 959         device_lock(&dev->dev);
 960
 961         if (dev->active_target && timer_pending(&dev->check_pres_timer) == 0) {
 962                 rc = dev->ops->check_presence(dev, dev->active_target);
 963                 if (rc == -EOPNOTSUPP)
 964                         goto exit;
 965                 if (rc) {
 966                         u32 active_target_idx = dev->active_target->idx;
 967                         device_unlock(&dev->dev);
 968                         nfc_target_lost(dev, active_target_idx);
 969                         return;
 970                 }
 971
 972                 if (!dev->shutting_down)
 973                         mod_timer(&dev->check_pres_timer, jiffies +
 974                                   msecs_to_jiffies(NFC_CHECK_PRES_FREQ_MS));
 975         }
 976
 977 exit:
 978         device_unlock(&dev->dev);
 979 }
 980
 981 static void nfc_check_pres_timeout(unsigned long data)
 982 {
 983         struct nfc_dev *dev = (struct nfc_dev *)data;
 984
 985         schedule_work(&dev->check_pres_work);
 986 }
 987
 988 struct class nfc_class = {
 989         .name = "nfc",
 990         .dev_release = nfc_release,
 991 };
 992 EXPORT_SYMBOL(nfc_class);
 993
 994 static int match_idx(struct device *d, const void *data)
 995 {
 996         struct nfc_dev *dev = to_nfc_dev(d);
 997         const unsigned int *idx = data;
 998
 999         return dev->idx == *idx;
1000 }
1001
1002 struct nfc_dev *nfc_get_device(unsigned int idx)
1003 {
1004         struct device *d;
1005
1006         d = class_find_device(&nfc_class, NULL, &idx, match_idx);
1007         if (!d)
1008                 return NULL;
1009
1010         return to_nfc_dev(d);
1011 }
1012
1013 /**
1014  * nfc_allocate_device - allocate a new nfc device
1015  *
1016  * @ops: device operations
1017  * @supported_protocols: NFC protocols supported by the device
1018  */
1019 struct nfc_dev *nfc_allocate_device(struct nfc_ops *ops,
1020                                     u32 supported_protocols,
1021                                     int tx_headroom, int tx_tailroom)
1022 {
1023         struct nfc_dev *dev;
1024
1025         if (!ops->start_poll || !ops->stop_poll || !ops->activate_target ||
1026             !ops->deactivate_target || !ops->im_transceive)
1027                 return NULL;
1028
1029         if (!supported_protocols)
1030                 return NULL;
1031
1032         dev = kzalloc(sizeof(struct nfc_dev), GFP_KERNEL);
1033         if (!dev)
1034                 return NULL;
1035
1036         dev->ops = ops;
1037         dev->supported_protocols = supported_protocols;
1038         dev->tx_headroom = tx_headroom;
1039         dev->tx_tailroom = tx_tailroom;
1040         INIT_LIST_HEAD(&dev->secure_elements);
1041
1042         nfc_genl_data_init(&dev->genl_data);
1043
1044         dev->rf_mode = NFC_RF_NONE;
1045
1046         /* first generation must not be 0 */
1047         dev->targets_generation = 1;
1048
1049         if (ops->check_presence) {
1050                 init_timer(&dev->check_pres_timer);
1051                 dev->check_pres_timer.data = (unsigned long)dev;
1052                 dev->check_pres_timer.function = nfc_check_pres_timeout;
1053
1054                 INIT_WORK(&dev->check_pres_work, nfc_check_pres_work);
1055         }
1056
1057         return dev;
1058 }
1059 EXPORT_SYMBOL(nfc_allocate_device);
1060
1061 /**
1062  * nfc_register_device - register a nfc device in the nfc subsystem
1063  *
1064  * @dev: The nfc device to register
1065  */
1066 int nfc_register_device(struct nfc_dev *dev)
1067 {
1068         int rc;
1069
1070         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
1071
1072         dev->idx = ida_simple_get(&nfc_index_ida, 0, 0, GFP_KERNEL);
1073         if (dev->idx < 0)
1074                 return dev->idx;
1075
1076         dev->dev.class = &nfc_class;
1077         dev_set_name(&dev->dev, "nfc%d", dev->idx);
1078         device_initialize(&dev->dev);
1079
1080         mutex_lock(&nfc_devlist_mutex);
1081         nfc_devlist_generation++;
1082         rc = device_add(&dev->dev);
1083         mutex_unlock(&nfc_devlist_mutex);
1084
1085         if (rc < 0)
1086                 return rc;
1087
1088         rc = nfc_llcp_register_device(dev);
1089         if (rc)
1090                 pr_err("Could not register llcp device\n");
1091
1092         rc = nfc_genl_device_added(dev);
1093         if (rc)
1094                 pr_debug("The userspace won't be notified that the device %s was added\n",
1095                          dev_name(&dev->dev));
1096
1097         dev->rfkill = rfkill_alloc(dev_name(&dev->dev), &dev->dev,
1098                                    RFKILL_TYPE_NFC, &nfc_rfkill_ops, dev);
1099         if (dev->rfkill) {
1100                 if (rfkill_register(dev->rfkill) < 0) {
1101                         rfkill_destroy(dev->rfkill);
1102                         dev->rfkill = NULL;
1103                 }
1104         }
1105
1106         return 0;
1107 }
1108 EXPORT_SYMBOL(nfc_register_device);
1109
1110 /**
1111  * nfc_unregister_device - unregister a nfc device in the nfc subsystem
1112  *
1113  * @dev: The nfc device to unregister
1114  */
1115 void nfc_unregister_device(struct nfc_dev *dev)
1116 {
1117         int rc, id;
1118
1119         pr_debug("dev_name=%s\n", dev_name(&dev->dev));
1120
1121         id = dev->idx;
1122
1123         if (dev->rfkill) {
1124                 rfkill_unregister(dev->rfkill);
1125                 rfkill_destroy(dev->rfkill);
1126         }
1127
1128         if (dev->ops->check_presence) {
1129                 device_lock(&dev->dev);
1130                 dev->shutting_down = true;
1131                 device_unlock(&dev->dev);
1132                 del_timer_sync(&dev->check_pres_timer);
1133                 cancel_work_sync(&dev->check_pres_work);
1134         }
1135
1136         rc = nfc_genl_device_removed(dev);
1137         if (rc)
1138                 pr_debug("The userspace won't be notified that the device %s "
1139                          "was removed\n", dev_name(&dev->dev));
1140
1141         nfc_llcp_unregister_device(dev);
1142
1143         mutex_lock(&nfc_devlist_mutex);
1144         nfc_devlist_generation++;
1145         device_del(&dev->dev);
1146         mutex_unlock(&nfc_devlist_mutex);
1147
1148         ida_simple_remove(&nfc_index_ida, id);
1149 }
1150 EXPORT_SYMBOL(nfc_unregister_device);
1151
1152 static int __init nfc_init(void)
1153 {
1154         int rc;
1155
1156         pr_info("NFC Core ver %s\n", VERSION);
1157
1158         rc = class_register(&nfc_class);
1159         if (rc)
1160                 return rc;
1161
1162         rc = nfc_genl_init();
1163         if (rc)
1164                 goto err_genl;
1165
1166         /* the first generation must not be 0 */
1167         nfc_devlist_generation = 1;
1168
1169         rc = rawsock_init();
1170         if (rc)
1171                 goto err_rawsock;
1172
1173         rc = nfc_llcp_init();
1174         if (rc)
1175                 goto err_llcp_sock;
1176
1177         rc = af_nfc_init();
1178         if (rc)
1179                 goto err_af_nfc;
1180
1181         return 0;
1182
1183 err_af_nfc:
1184         nfc_llcp_exit();
1185 err_llcp_sock:
1186         rawsock_exit();
1187 err_rawsock:
1188         nfc_genl_exit();
1189 err_genl:
1190         class_unregister(&nfc_class);
1191         return rc;
1192 }
1193
1194 static void __exit nfc_exit(void)
1195 {
1196         af_nfc_exit();
1197         nfc_llcp_exit();
1198         rawsock_exit();
1199         nfc_genl_exit();
1200         class_unregister(&nfc_class);
1201 }
1202
1203 subsys_initcall(nfc_init);
1204 module_exit(nfc_exit);
1205
1206 MODULE_AUTHOR("Lauro Ramos Venancio <lauro.venancio@openbossa.org>");
1207 MODULE_DESCRIPTION("NFC Core ver " VERSION);
1208 MODULE_VERSION(VERSION);
1209 MODULE_LICENSE("GPL");
1210 MODULE_ALIAS_NETPROTO(PF_NFC);
1211 MODULE_ALIAS_GENL_FAMILY(NFC_GENL_NAME);