linux/net/nfc/nci/core.c
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   1/*
   2 *  The NFC Controller Interface is the communication protocol between an
   3 *  NFC Controller (NFCC) and a Device Host (DH).
   4 *
   5 *  Copyright (C) 2011 Texas Instruments, Inc.
   6 *
   7 *  Written by Ilan Elias <ilane@ti.com>
   8 *
   9 *  Acknowledgements:
  10 *  This file is based on hci_core.c, which was written
  11 *  by Maxim Krasnyansky.
  12 *
  13 *  This program is free software; you can redistribute it and/or modify
  14 *  it under the terms of the GNU General Public License version 2
  15 *  as published by the Free Software Foundation
  16 *
  17 *  This program is distributed in the hope that it will be useful,
  18 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 *  GNU General Public License for more details.
  21 *
  22 *  You should have received a copy of the GNU General Public License
  23 *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  24 *
  25 */
  26
  27#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
  28
  29#include <linux/module.h>
  30#include <linux/types.h>
  31#include <linux/workqueue.h>
  32#include <linux/completion.h>
  33#include <linux/export.h>
  34#include <linux/sched.h>
  35#include <linux/bitops.h>
  36#include <linux/skbuff.h>
  37
  38#include "../nfc.h"
  39#include <net/nfc/nci.h>
  40#include <net/nfc/nci_core.h>
  41#include <linux/nfc.h>
  42
  43static void nci_cmd_work(struct work_struct *work);
  44static void nci_rx_work(struct work_struct *work);
  45static void nci_tx_work(struct work_struct *work);
  46
  47/* ---- NCI requests ---- */
  48
  49void nci_req_complete(struct nci_dev *ndev, int result)
  50{
  51        if (ndev->req_status == NCI_REQ_PEND) {
  52                ndev->req_result = result;
  53                ndev->req_status = NCI_REQ_DONE;
  54                complete(&ndev->req_completion);
  55        }
  56}
  57
  58static void nci_req_cancel(struct nci_dev *ndev, int err)
  59{
  60        if (ndev->req_status == NCI_REQ_PEND) {
  61                ndev->req_result = err;
  62                ndev->req_status = NCI_REQ_CANCELED;
  63                complete(&ndev->req_completion);
  64        }
  65}
  66
  67/* Execute request and wait for completion. */
  68static int __nci_request(struct nci_dev *ndev,
  69                         void (*req)(struct nci_dev *ndev, unsigned long opt),
  70                         unsigned long opt, __u32 timeout)
  71{
  72        int rc = 0;
  73        long completion_rc;
  74
  75        ndev->req_status = NCI_REQ_PEND;
  76
  77        reinit_completion(&ndev->req_completion);
  78        req(ndev, opt);
  79        completion_rc =
  80                wait_for_completion_interruptible_timeout(&ndev->req_completion,
  81                                                          timeout);
  82
  83        pr_debug("wait_for_completion return %ld\n", completion_rc);
  84
  85        if (completion_rc > 0) {
  86                switch (ndev->req_status) {
  87                case NCI_REQ_DONE:
  88                        rc = nci_to_errno(ndev->req_result);
  89                        break;
  90
  91                case NCI_REQ_CANCELED:
  92                        rc = -ndev->req_result;
  93                        break;
  94
  95                default:
  96                        rc = -ETIMEDOUT;
  97                        break;
  98                }
  99        } else {
 100                pr_err("wait_for_completion_interruptible_timeout failed %ld\n",
 101                       completion_rc);
 102
 103                rc = ((completion_rc == 0) ? (-ETIMEDOUT) : (completion_rc));
 104        }
 105
 106        ndev->req_status = ndev->req_result = 0;
 107
 108        return rc;
 109}
 110
 111static inline int nci_request(struct nci_dev *ndev,
 112                              void (*req)(struct nci_dev *ndev,
 113                                          unsigned long opt),
 114                              unsigned long opt, __u32 timeout)
 115{
 116        int rc;
 117
 118        if (!test_bit(NCI_UP, &ndev->flags))
 119                return -ENETDOWN;
 120
 121        /* Serialize all requests */
 122        mutex_lock(&ndev->req_lock);
 123        rc = __nci_request(ndev, req, opt, timeout);
 124        mutex_unlock(&ndev->req_lock);
 125
 126        return rc;
 127}
 128
 129static void nci_reset_req(struct nci_dev *ndev, unsigned long opt)
 130{
 131        struct nci_core_reset_cmd cmd;
 132
 133        cmd.reset_type = NCI_RESET_TYPE_RESET_CONFIG;
 134        nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 1, &cmd);
 135}
 136
 137static void nci_init_req(struct nci_dev *ndev, unsigned long opt)
 138{
 139        nci_send_cmd(ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);
 140}
 141
 142static void nci_init_complete_req(struct nci_dev *ndev, unsigned long opt)
 143{
 144        struct nci_rf_disc_map_cmd cmd;
 145        struct disc_map_config *cfg = cmd.mapping_configs;
 146        __u8 *num = &cmd.num_mapping_configs;
 147        int i;
 148
 149        /* set rf mapping configurations */
 150        *num = 0;
 151
 152        /* by default mapping is set to NCI_RF_INTERFACE_FRAME */
 153        for (i = 0; i < ndev->num_supported_rf_interfaces; i++) {
 154                if (ndev->supported_rf_interfaces[i] ==
 155                    NCI_RF_INTERFACE_ISO_DEP) {
 156                        cfg[*num].rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
 157                        cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
 158                                NCI_DISC_MAP_MODE_LISTEN;
 159                        cfg[*num].rf_interface = NCI_RF_INTERFACE_ISO_DEP;
 160                        (*num)++;
 161                } else if (ndev->supported_rf_interfaces[i] ==
 162                           NCI_RF_INTERFACE_NFC_DEP) {
 163                        cfg[*num].rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
 164                        cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
 165                                NCI_DISC_MAP_MODE_LISTEN;
 166                        cfg[*num].rf_interface = NCI_RF_INTERFACE_NFC_DEP;
 167                        (*num)++;
 168                }
 169
 170                if (*num == NCI_MAX_NUM_MAPPING_CONFIGS)
 171                        break;
 172        }
 173
 174        nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD,
 175                     (1 + ((*num) * sizeof(struct disc_map_config))), &cmd);
 176}
 177
 178struct nci_set_config_param {
 179        __u8    id;
 180        size_t  len;
 181        __u8    *val;
 182};
 183
 184static void nci_set_config_req(struct nci_dev *ndev, unsigned long opt)
 185{
 186        struct nci_set_config_param *param = (struct nci_set_config_param *)opt;
 187        struct nci_core_set_config_cmd cmd;
 188
 189        BUG_ON(param->len > NCI_MAX_PARAM_LEN);
 190
 191        cmd.num_params = 1;
 192        cmd.param.id = param->id;
 193        cmd.param.len = param->len;
 194        memcpy(cmd.param.val, param->val, param->len);
 195
 196        nci_send_cmd(ndev, NCI_OP_CORE_SET_CONFIG_CMD, (3 + param->len), &cmd);
 197}
 198
 199static void nci_rf_discover_req(struct nci_dev *ndev, unsigned long opt)
 200{
 201        struct nci_rf_disc_cmd cmd;
 202        __u32 protocols = opt;
 203
 204        cmd.num_disc_configs = 0;
 205
 206        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 207            (protocols & NFC_PROTO_JEWEL_MASK ||
 208             protocols & NFC_PROTO_MIFARE_MASK ||
 209             protocols & NFC_PROTO_ISO14443_MASK ||
 210             protocols & NFC_PROTO_NFC_DEP_MASK)) {
 211                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 212                        NCI_NFC_A_PASSIVE_POLL_MODE;
 213                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 214                cmd.num_disc_configs++;
 215        }
 216
 217        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 218            (protocols & NFC_PROTO_ISO14443_B_MASK)) {
 219                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 220                        NCI_NFC_B_PASSIVE_POLL_MODE;
 221                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 222                cmd.num_disc_configs++;
 223        }
 224
 225        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 226            (protocols & NFC_PROTO_FELICA_MASK ||
 227             protocols & NFC_PROTO_NFC_DEP_MASK)) {
 228                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 229                        NCI_NFC_F_PASSIVE_POLL_MODE;
 230                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 231                cmd.num_disc_configs++;
 232        }
 233
 234        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 235            (protocols & NFC_PROTO_ISO15693_MASK)) {
 236                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 237                        NCI_NFC_V_PASSIVE_POLL_MODE;
 238                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 239                cmd.num_disc_configs++;
 240        }
 241
 242        nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_CMD,
 243                     (1 + (cmd.num_disc_configs * sizeof(struct disc_config))),
 244                     &cmd);
 245}
 246
 247struct nci_rf_discover_select_param {
 248        __u8    rf_discovery_id;
 249        __u8    rf_protocol;
 250};
 251
 252static void nci_rf_discover_select_req(struct nci_dev *ndev, unsigned long opt)
 253{
 254        struct nci_rf_discover_select_param *param =
 255                (struct nci_rf_discover_select_param *)opt;
 256        struct nci_rf_discover_select_cmd cmd;
 257
 258        cmd.rf_discovery_id = param->rf_discovery_id;
 259        cmd.rf_protocol = param->rf_protocol;
 260
 261        switch (cmd.rf_protocol) {
 262        case NCI_RF_PROTOCOL_ISO_DEP:
 263                cmd.rf_interface = NCI_RF_INTERFACE_ISO_DEP;
 264                break;
 265
 266        case NCI_RF_PROTOCOL_NFC_DEP:
 267                cmd.rf_interface = NCI_RF_INTERFACE_NFC_DEP;
 268                break;
 269
 270        default:
 271                cmd.rf_interface = NCI_RF_INTERFACE_FRAME;
 272                break;
 273        }
 274
 275        nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_SELECT_CMD,
 276                     sizeof(struct nci_rf_discover_select_cmd), &cmd);
 277}
 278
 279static void nci_rf_deactivate_req(struct nci_dev *ndev, unsigned long opt)
 280{
 281        struct nci_rf_deactivate_cmd cmd;
 282
 283        cmd.type = NCI_DEACTIVATE_TYPE_IDLE_MODE;
 284
 285        nci_send_cmd(ndev, NCI_OP_RF_DEACTIVATE_CMD,
 286                     sizeof(struct nci_rf_deactivate_cmd), &cmd);
 287}
 288
 289static int nci_open_device(struct nci_dev *ndev)
 290{
 291        int rc = 0;
 292
 293        mutex_lock(&ndev->req_lock);
 294
 295        if (test_bit(NCI_UP, &ndev->flags)) {
 296                rc = -EALREADY;
 297                goto done;
 298        }
 299
 300        if (ndev->ops->open(ndev)) {
 301                rc = -EIO;
 302                goto done;
 303        }
 304
 305        atomic_set(&ndev->cmd_cnt, 1);
 306
 307        set_bit(NCI_INIT, &ndev->flags);
 308
 309        rc = __nci_request(ndev, nci_reset_req, 0,
 310                           msecs_to_jiffies(NCI_RESET_TIMEOUT));
 311
 312        if (ndev->ops->setup)
 313                ndev->ops->setup(ndev);
 314
 315        if (!rc) {
 316                rc = __nci_request(ndev, nci_init_req, 0,
 317                                   msecs_to_jiffies(NCI_INIT_TIMEOUT));
 318        }
 319
 320        if (!rc) {
 321                rc = __nci_request(ndev, nci_init_complete_req, 0,
 322                                   msecs_to_jiffies(NCI_INIT_TIMEOUT));
 323        }
 324
 325        clear_bit(NCI_INIT, &ndev->flags);
 326
 327        if (!rc) {
 328                set_bit(NCI_UP, &ndev->flags);
 329                nci_clear_target_list(ndev);
 330                atomic_set(&ndev->state, NCI_IDLE);
 331        } else {
 332                /* Init failed, cleanup */
 333                skb_queue_purge(&ndev->cmd_q);
 334                skb_queue_purge(&ndev->rx_q);
 335                skb_queue_purge(&ndev->tx_q);
 336
 337                ndev->ops->close(ndev);
 338                ndev->flags = 0;
 339        }
 340
 341done:
 342        mutex_unlock(&ndev->req_lock);
 343        return rc;
 344}
 345
 346static int nci_close_device(struct nci_dev *ndev)
 347{
 348        nci_req_cancel(ndev, ENODEV);
 349        mutex_lock(&ndev->req_lock);
 350
 351        if (!test_and_clear_bit(NCI_UP, &ndev->flags)) {
 352                del_timer_sync(&ndev->cmd_timer);
 353                del_timer_sync(&ndev->data_timer);
 354                mutex_unlock(&ndev->req_lock);
 355                return 0;
 356        }
 357
 358        /* Drop RX and TX queues */
 359        skb_queue_purge(&ndev->rx_q);
 360        skb_queue_purge(&ndev->tx_q);
 361
 362        /* Flush RX and TX wq */
 363        flush_workqueue(ndev->rx_wq);
 364        flush_workqueue(ndev->tx_wq);
 365
 366        /* Reset device */
 367        skb_queue_purge(&ndev->cmd_q);
 368        atomic_set(&ndev->cmd_cnt, 1);
 369
 370        set_bit(NCI_INIT, &ndev->flags);
 371        __nci_request(ndev, nci_reset_req, 0,
 372                      msecs_to_jiffies(NCI_RESET_TIMEOUT));
 373        clear_bit(NCI_INIT, &ndev->flags);
 374
 375        del_timer_sync(&ndev->cmd_timer);
 376
 377        /* Flush cmd wq */
 378        flush_workqueue(ndev->cmd_wq);
 379
 380        /* After this point our queues are empty
 381         * and no works are scheduled. */
 382        ndev->ops->close(ndev);
 383
 384        /* Clear flags */
 385        ndev->flags = 0;
 386
 387        mutex_unlock(&ndev->req_lock);
 388
 389        return 0;
 390}
 391
 392/* NCI command timer function */
 393static void nci_cmd_timer(unsigned long arg)
 394{
 395        struct nci_dev *ndev = (void *) arg;
 396
 397        atomic_set(&ndev->cmd_cnt, 1);
 398        queue_work(ndev->cmd_wq, &ndev->cmd_work);
 399}
 400
 401/* NCI data exchange timer function */
 402static void nci_data_timer(unsigned long arg)
 403{
 404        struct nci_dev *ndev = (void *) arg;
 405
 406        set_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
 407        queue_work(ndev->rx_wq, &ndev->rx_work);
 408}
 409
 410static int nci_dev_up(struct nfc_dev *nfc_dev)
 411{
 412        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 413
 414        return nci_open_device(ndev);
 415}
 416
 417static int nci_dev_down(struct nfc_dev *nfc_dev)
 418{
 419        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 420
 421        return nci_close_device(ndev);
 422}
 423
 424int nci_set_config(struct nci_dev *ndev, __u8 id, size_t len, __u8 *val)
 425{
 426        struct nci_set_config_param param;
 427
 428        if (!val || !len)
 429                return 0;
 430
 431        param.id = id;
 432        param.len = len;
 433        param.val = val;
 434
 435        return __nci_request(ndev, nci_set_config_req, (unsigned long)&param,
 436                             msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
 437}
 438EXPORT_SYMBOL(nci_set_config);
 439
 440static int nci_set_local_general_bytes(struct nfc_dev *nfc_dev)
 441{
 442        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 443        struct nci_set_config_param param;
 444
 445        param.val = nfc_get_local_general_bytes(nfc_dev, &param.len);
 446        if ((param.val == NULL) || (param.len == 0))
 447                return 0;
 448
 449        if (param.len > NFC_MAX_GT_LEN)
 450                return -EINVAL;
 451
 452        param.id = NCI_PN_ATR_REQ_GEN_BYTES;
 453
 454        return nci_request(ndev, nci_set_config_req, (unsigned long)&param,
 455                           msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
 456}
 457
 458static int nci_start_poll(struct nfc_dev *nfc_dev,
 459                          __u32 im_protocols, __u32 tm_protocols)
 460{
 461        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 462        int rc;
 463
 464        if ((atomic_read(&ndev->state) == NCI_DISCOVERY) ||
 465            (atomic_read(&ndev->state) == NCI_W4_ALL_DISCOVERIES)) {
 466                pr_err("unable to start poll, since poll is already active\n");
 467                return -EBUSY;
 468        }
 469
 470        if (ndev->target_active_prot) {
 471                pr_err("there is an active target\n");
 472                return -EBUSY;
 473        }
 474
 475        if ((atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) ||
 476            (atomic_read(&ndev->state) == NCI_POLL_ACTIVE)) {
 477                pr_debug("target active or w4 select, implicitly deactivate\n");
 478
 479                rc = nci_request(ndev, nci_rf_deactivate_req, 0,
 480                                 msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
 481                if (rc)
 482                        return -EBUSY;
 483        }
 484
 485        if (im_protocols & NFC_PROTO_NFC_DEP_MASK) {
 486                rc = nci_set_local_general_bytes(nfc_dev);
 487                if (rc) {
 488                        pr_err("failed to set local general bytes\n");
 489                        return rc;
 490                }
 491        }
 492
 493        rc = nci_request(ndev, nci_rf_discover_req, im_protocols,
 494                         msecs_to_jiffies(NCI_RF_DISC_TIMEOUT));
 495
 496        if (!rc)
 497                ndev->poll_prots = im_protocols;
 498
 499        return rc;
 500}
 501
 502static void nci_stop_poll(struct nfc_dev *nfc_dev)
 503{
 504        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 505
 506        if ((atomic_read(&ndev->state) != NCI_DISCOVERY) &&
 507            (atomic_read(&ndev->state) != NCI_W4_ALL_DISCOVERIES)) {
 508                pr_err("unable to stop poll, since poll is not active\n");
 509                return;
 510        }
 511
 512        nci_request(ndev, nci_rf_deactivate_req, 0,
 513                    msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
 514}
 515
 516static int nci_activate_target(struct nfc_dev *nfc_dev,
 517                               struct nfc_target *target, __u32 protocol)
 518{
 519        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 520        struct nci_rf_discover_select_param param;
 521        struct nfc_target *nci_target = NULL;
 522        int i;
 523        int rc = 0;
 524
 525        pr_debug("target_idx %d, protocol 0x%x\n", target->idx, protocol);
 526
 527        if ((atomic_read(&ndev->state) != NCI_W4_HOST_SELECT) &&
 528            (atomic_read(&ndev->state) != NCI_POLL_ACTIVE)) {
 529                pr_err("there is no available target to activate\n");
 530                return -EINVAL;
 531        }
 532
 533        if (ndev->target_active_prot) {
 534                pr_err("there is already an active target\n");
 535                return -EBUSY;
 536        }
 537
 538        for (i = 0; i < ndev->n_targets; i++) {
 539                if (ndev->targets[i].idx == target->idx) {
 540                        nci_target = &ndev->targets[i];
 541                        break;
 542                }
 543        }
 544
 545        if (!nci_target) {
 546                pr_err("unable to find the selected target\n");
 547                return -EINVAL;
 548        }
 549
 550        if (!(nci_target->supported_protocols & (1 << protocol))) {
 551                pr_err("target does not support the requested protocol 0x%x\n",
 552                       protocol);
 553                return -EINVAL;
 554        }
 555
 556        if (atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) {
 557                param.rf_discovery_id = nci_target->logical_idx;
 558
 559                if (protocol == NFC_PROTO_JEWEL)
 560                        param.rf_protocol = NCI_RF_PROTOCOL_T1T;
 561                else if (protocol == NFC_PROTO_MIFARE)
 562                        param.rf_protocol = NCI_RF_PROTOCOL_T2T;
 563                else if (protocol == NFC_PROTO_FELICA)
 564                        param.rf_protocol = NCI_RF_PROTOCOL_T3T;
 565                else if (protocol == NFC_PROTO_ISO14443 ||
 566                         protocol == NFC_PROTO_ISO14443_B)
 567                        param.rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
 568                else
 569                        param.rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
 570
 571                rc = nci_request(ndev, nci_rf_discover_select_req,
 572                                 (unsigned long)&param,
 573                                 msecs_to_jiffies(NCI_RF_DISC_SELECT_TIMEOUT));
 574        }
 575
 576        if (!rc)
 577                ndev->target_active_prot = protocol;
 578
 579        return rc;
 580}
 581
 582static void nci_deactivate_target(struct nfc_dev *nfc_dev,
 583                                  struct nfc_target *target)
 584{
 585        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 586
 587        pr_debug("entry\n");
 588
 589        if (!ndev->target_active_prot) {
 590                pr_err("unable to deactivate target, no active target\n");
 591                return;
 592        }
 593
 594        ndev->target_active_prot = 0;
 595
 596        if (atomic_read(&ndev->state) == NCI_POLL_ACTIVE) {
 597                nci_request(ndev, nci_rf_deactivate_req, 0,
 598                            msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
 599        }
 600}
 601
 602static int nci_dep_link_up(struct nfc_dev *nfc_dev, struct nfc_target *target,
 603                           __u8 comm_mode, __u8 *gb, size_t gb_len)
 604{
 605        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 606        int rc;
 607
 608        pr_debug("target_idx %d, comm_mode %d\n", target->idx, comm_mode);
 609
 610        rc = nci_activate_target(nfc_dev, target, NFC_PROTO_NFC_DEP);
 611        if (rc)
 612                return rc;
 613
 614        rc = nfc_set_remote_general_bytes(nfc_dev, ndev->remote_gb,
 615                                          ndev->remote_gb_len);
 616        if (!rc)
 617                rc = nfc_dep_link_is_up(nfc_dev, target->idx, NFC_COMM_PASSIVE,
 618                                        NFC_RF_INITIATOR);
 619
 620        return rc;
 621}
 622
 623static int nci_dep_link_down(struct nfc_dev *nfc_dev)
 624{
 625        pr_debug("entry\n");
 626
 627        nci_deactivate_target(nfc_dev, NULL);
 628
 629        return 0;
 630}
 631
 632
 633static int nci_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target,
 634                          struct sk_buff *skb,
 635                          data_exchange_cb_t cb, void *cb_context)
 636{
 637        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 638        int rc;
 639
 640        pr_debug("target_idx %d, len %d\n", target->idx, skb->len);
 641
 642        if (!ndev->target_active_prot) {
 643                pr_err("unable to exchange data, no active target\n");
 644                return -EINVAL;
 645        }
 646
 647        if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
 648                return -EBUSY;
 649
 650        /* store cb and context to be used on receiving data */
 651        ndev->data_exchange_cb = cb;
 652        ndev->data_exchange_cb_context = cb_context;
 653
 654        rc = nci_send_data(ndev, NCI_STATIC_RF_CONN_ID, skb);
 655        if (rc)
 656                clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
 657
 658        return rc;
 659}
 660
 661static int nci_enable_se(struct nfc_dev *nfc_dev, u32 se_idx)
 662{
 663        return 0;
 664}
 665
 666static int nci_disable_se(struct nfc_dev *nfc_dev, u32 se_idx)
 667{
 668        return 0;
 669}
 670
 671static int nci_discover_se(struct nfc_dev *nfc_dev)
 672{
 673        return 0;
 674}
 675
 676static struct nfc_ops nci_nfc_ops = {
 677        .dev_up = nci_dev_up,
 678        .dev_down = nci_dev_down,
 679        .start_poll = nci_start_poll,
 680        .stop_poll = nci_stop_poll,
 681        .dep_link_up = nci_dep_link_up,
 682        .dep_link_down = nci_dep_link_down,
 683        .activate_target = nci_activate_target,
 684        .deactivate_target = nci_deactivate_target,
 685        .im_transceive = nci_transceive,
 686        .enable_se = nci_enable_se,
 687        .disable_se = nci_disable_se,
 688        .discover_se = nci_discover_se,
 689};
 690
 691/* ---- Interface to NCI drivers ---- */
 692
 693/**
 694 * nci_allocate_device - allocate a new nci device
 695 *
 696 * @ops: device operations
 697 * @supported_protocols: NFC protocols supported by the device
 698 */
 699struct nci_dev *nci_allocate_device(struct nci_ops *ops,
 700                                    __u32 supported_protocols,
 701                                    int tx_headroom, int tx_tailroom)
 702{
 703        struct nci_dev *ndev;
 704
 705        pr_debug("supported_protocols 0x%x\n", supported_protocols);
 706
 707        if (!ops->open || !ops->close || !ops->send)
 708                return NULL;
 709
 710        if (!supported_protocols)
 711                return NULL;
 712
 713        ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL);
 714        if (!ndev)
 715                return NULL;
 716
 717        ndev->ops = ops;
 718        ndev->tx_headroom = tx_headroom;
 719        ndev->tx_tailroom = tx_tailroom;
 720        init_completion(&ndev->req_completion);
 721
 722        ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
 723                                            supported_protocols,
 724                                            tx_headroom + NCI_DATA_HDR_SIZE,
 725                                            tx_tailroom);
 726        if (!ndev->nfc_dev)
 727                goto free_exit;
 728
 729        nfc_set_drvdata(ndev->nfc_dev, ndev);
 730
 731        return ndev;
 732
 733free_exit:
 734        kfree(ndev);
 735        return NULL;
 736}
 737EXPORT_SYMBOL(nci_allocate_device);
 738
 739/**
 740 * nci_free_device - deallocate nci device
 741 *
 742 * @ndev: The nci device to deallocate
 743 */
 744void nci_free_device(struct nci_dev *ndev)
 745{
 746        nfc_free_device(ndev->nfc_dev);
 747        kfree(ndev);
 748}
 749EXPORT_SYMBOL(nci_free_device);
 750
 751/**
 752 * nci_register_device - register a nci device in the nfc subsystem
 753 *
 754 * @dev: The nci device to register
 755 */
 756int nci_register_device(struct nci_dev *ndev)
 757{
 758        int rc;
 759        struct device *dev = &ndev->nfc_dev->dev;
 760        char name[32];
 761
 762        ndev->flags = 0;
 763
 764        INIT_WORK(&ndev->cmd_work, nci_cmd_work);
 765        snprintf(name, sizeof(name), "%s_nci_cmd_wq", dev_name(dev));
 766        ndev->cmd_wq = create_singlethread_workqueue(name);
 767        if (!ndev->cmd_wq) {
 768                rc = -ENOMEM;
 769                goto exit;
 770        }
 771
 772        INIT_WORK(&ndev->rx_work, nci_rx_work);
 773        snprintf(name, sizeof(name), "%s_nci_rx_wq", dev_name(dev));
 774        ndev->rx_wq = create_singlethread_workqueue(name);
 775        if (!ndev->rx_wq) {
 776                rc = -ENOMEM;
 777                goto destroy_cmd_wq_exit;
 778        }
 779
 780        INIT_WORK(&ndev->tx_work, nci_tx_work);
 781        snprintf(name, sizeof(name), "%s_nci_tx_wq", dev_name(dev));
 782        ndev->tx_wq = create_singlethread_workqueue(name);
 783        if (!ndev->tx_wq) {
 784                rc = -ENOMEM;
 785                goto destroy_rx_wq_exit;
 786        }
 787
 788        skb_queue_head_init(&ndev->cmd_q);
 789        skb_queue_head_init(&ndev->rx_q);
 790        skb_queue_head_init(&ndev->tx_q);
 791
 792        setup_timer(&ndev->cmd_timer, nci_cmd_timer,
 793                    (unsigned long) ndev);
 794        setup_timer(&ndev->data_timer, nci_data_timer,
 795                    (unsigned long) ndev);
 796
 797        mutex_init(&ndev->req_lock);
 798
 799        rc = nfc_register_device(ndev->nfc_dev);
 800        if (rc)
 801                goto destroy_rx_wq_exit;
 802
 803        goto exit;
 804
 805destroy_rx_wq_exit:
 806        destroy_workqueue(ndev->rx_wq);
 807
 808destroy_cmd_wq_exit:
 809        destroy_workqueue(ndev->cmd_wq);
 810
 811exit:
 812        return rc;
 813}
 814EXPORT_SYMBOL(nci_register_device);
 815
 816/**
 817 * nci_unregister_device - unregister a nci device in the nfc subsystem
 818 *
 819 * @dev: The nci device to unregister
 820 */
 821void nci_unregister_device(struct nci_dev *ndev)
 822{
 823        nci_close_device(ndev);
 824
 825        destroy_workqueue(ndev->cmd_wq);
 826        destroy_workqueue(ndev->rx_wq);
 827        destroy_workqueue(ndev->tx_wq);
 828
 829        nfc_unregister_device(ndev->nfc_dev);
 830}
 831EXPORT_SYMBOL(nci_unregister_device);
 832
 833/**
 834 * nci_recv_frame - receive frame from NCI drivers
 835 *
 836 * @ndev: The nci device
 837 * @skb: The sk_buff to receive
 838 */
 839int nci_recv_frame(struct nci_dev *ndev, struct sk_buff *skb)
 840{
 841        pr_debug("len %d\n", skb->len);
 842
 843        if (!ndev || (!test_bit(NCI_UP, &ndev->flags) &&
 844            !test_bit(NCI_INIT, &ndev->flags))) {
 845                kfree_skb(skb);
 846                return -ENXIO;
 847        }
 848
 849        /* Queue frame for rx worker thread */
 850        skb_queue_tail(&ndev->rx_q, skb);
 851        queue_work(ndev->rx_wq, &ndev->rx_work);
 852
 853        return 0;
 854}
 855EXPORT_SYMBOL(nci_recv_frame);
 856
 857static int nci_send_frame(struct nci_dev *ndev, struct sk_buff *skb)
 858{
 859        pr_debug("len %d\n", skb->len);
 860
 861        if (!ndev) {
 862                kfree_skb(skb);
 863                return -ENODEV;
 864        }
 865
 866        /* Get rid of skb owner, prior to sending to the driver. */
 867        skb_orphan(skb);
 868
 869        /* Send copy to sniffer */
 870        nfc_send_to_raw_sock(ndev->nfc_dev, skb,
 871                             RAW_PAYLOAD_NCI, NFC_DIRECTION_TX);
 872
 873        return ndev->ops->send(ndev, skb);
 874}
 875
 876/* Send NCI command */
 877int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload)
 878{
 879        struct nci_ctrl_hdr *hdr;
 880        struct sk_buff *skb;
 881
 882        pr_debug("opcode 0x%x, plen %d\n", opcode, plen);
 883
 884        skb = nci_skb_alloc(ndev, (NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
 885        if (!skb) {
 886                pr_err("no memory for command\n");
 887                return -ENOMEM;
 888        }
 889
 890        hdr = (struct nci_ctrl_hdr *) skb_put(skb, NCI_CTRL_HDR_SIZE);
 891        hdr->gid = nci_opcode_gid(opcode);
 892        hdr->oid = nci_opcode_oid(opcode);
 893        hdr->plen = plen;
 894
 895        nci_mt_set((__u8 *)hdr, NCI_MT_CMD_PKT);
 896        nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);
 897
 898        if (plen)
 899                memcpy(skb_put(skb, plen), payload, plen);
 900
 901        skb_queue_tail(&ndev->cmd_q, skb);
 902        queue_work(ndev->cmd_wq, &ndev->cmd_work);
 903
 904        return 0;
 905}
 906
 907/* ---- NCI TX Data worker thread ---- */
 908
 909static void nci_tx_work(struct work_struct *work)
 910{
 911        struct nci_dev *ndev = container_of(work, struct nci_dev, tx_work);
 912        struct sk_buff *skb;
 913
 914        pr_debug("credits_cnt %d\n", atomic_read(&ndev->credits_cnt));
 915
 916        /* Send queued tx data */
 917        while (atomic_read(&ndev->credits_cnt)) {
 918                skb = skb_dequeue(&ndev->tx_q);
 919                if (!skb)
 920                        return;
 921
 922                /* Check if data flow control is used */
 923                if (atomic_read(&ndev->credits_cnt) !=
 924                    NCI_DATA_FLOW_CONTROL_NOT_USED)
 925                        atomic_dec(&ndev->credits_cnt);
 926
 927                pr_debug("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d\n",
 928                         nci_pbf(skb->data),
 929                         nci_conn_id(skb->data),
 930                         nci_plen(skb->data));
 931
 932                nci_send_frame(ndev, skb);
 933
 934                mod_timer(&ndev->data_timer,
 935                          jiffies + msecs_to_jiffies(NCI_DATA_TIMEOUT));
 936        }
 937}
 938
 939/* ----- NCI RX worker thread (data & control) ----- */
 940
 941static void nci_rx_work(struct work_struct *work)
 942{
 943        struct nci_dev *ndev = container_of(work, struct nci_dev, rx_work);
 944        struct sk_buff *skb;
 945
 946        while ((skb = skb_dequeue(&ndev->rx_q))) {
 947
 948                /* Send copy to sniffer */
 949                nfc_send_to_raw_sock(ndev->nfc_dev, skb,
 950                                     RAW_PAYLOAD_NCI, NFC_DIRECTION_RX);
 951
 952                /* Process frame */
 953                switch (nci_mt(skb->data)) {
 954                case NCI_MT_RSP_PKT:
 955                        nci_rsp_packet(ndev, skb);
 956                        break;
 957
 958                case NCI_MT_NTF_PKT:
 959                        nci_ntf_packet(ndev, skb);
 960                        break;
 961
 962                case NCI_MT_DATA_PKT:
 963                        nci_rx_data_packet(ndev, skb);
 964                        break;
 965
 966                default:
 967                        pr_err("unknown MT 0x%x\n", nci_mt(skb->data));
 968                        kfree_skb(skb);
 969                        break;
 970                }
 971        }
 972
 973        /* check if a data exchange timout has occurred */
 974        if (test_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags)) {
 975                /* complete the data exchange transaction, if exists */
 976                if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
 977                        nci_data_exchange_complete(ndev, NULL, -ETIMEDOUT);
 978
 979                clear_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
 980        }
 981}
 982
 983/* ----- NCI TX CMD worker thread ----- */
 984
 985static void nci_cmd_work(struct work_struct *work)
 986{
 987        struct nci_dev *ndev = container_of(work, struct nci_dev, cmd_work);
 988        struct sk_buff *skb;
 989
 990        pr_debug("cmd_cnt %d\n", atomic_read(&ndev->cmd_cnt));
 991
 992        /* Send queued command */
 993        if (atomic_read(&ndev->cmd_cnt)) {
 994                skb = skb_dequeue(&ndev->cmd_q);
 995                if (!skb)
 996                        return;
 997
 998                atomic_dec(&ndev->cmd_cnt);
 999
1000                pr_debug("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
1001                         nci_pbf(skb->data),
1002                         nci_opcode_gid(nci_opcode(skb->data)),
1003                         nci_opcode_oid(nci_opcode(skb->data)),
1004                         nci_plen(skb->data));
1005
1006                nci_send_frame(ndev, skb);
1007
1008                mod_timer(&ndev->cmd_timer,
1009                          jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT));
1010        }
1011}
1012
1013MODULE_LICENSE("GPL");
1014