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, write to the Free Software
  24 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  25 *
  26 */
  27
  28#define pr_fmt(fmt) KBUILD_MODNAME ": %s: " fmt, __func__
  29
  30#include <linux/module.h>
  31#include <linux/types.h>
  32#include <linux/workqueue.h>
  33#include <linux/completion.h>
  34#include <linux/export.h>
  35#include <linux/sched.h>
  36#include <linux/bitops.h>
  37#include <linux/skbuff.h>
  38
  39#include "../nfc.h"
  40#include <net/nfc/nci.h>
  41#include <net/nfc/nci_core.h>
  42#include <linux/nfc.h>
  43
  44static void nci_cmd_work(struct work_struct *work);
  45static void nci_rx_work(struct work_struct *work);
  46static void nci_tx_work(struct work_struct *work);
  47
  48/* ---- NCI requests ---- */
  49
  50void nci_req_complete(struct nci_dev *ndev, int result)
  51{
  52        if (ndev->req_status == NCI_REQ_PEND) {
  53                ndev->req_result = result;
  54                ndev->req_status = NCI_REQ_DONE;
  55                complete(&ndev->req_completion);
  56        }
  57}
  58
  59static void nci_req_cancel(struct nci_dev *ndev, int err)
  60{
  61        if (ndev->req_status == NCI_REQ_PEND) {
  62                ndev->req_result = err;
  63                ndev->req_status = NCI_REQ_CANCELED;
  64                complete(&ndev->req_completion);
  65        }
  66}
  67
  68/* Execute request and wait for completion. */
  69static int __nci_request(struct nci_dev *ndev,
  70                         void (*req)(struct nci_dev *ndev, unsigned long opt),
  71                         unsigned long opt, __u32 timeout)
  72{
  73        int rc = 0;
  74        long completion_rc;
  75
  76        ndev->req_status = NCI_REQ_PEND;
  77
  78        init_completion(&ndev->req_completion);
  79        req(ndev, opt);
  80        completion_rc =
  81                wait_for_completion_interruptible_timeout(&ndev->req_completion,
  82                                                          timeout);
  83
  84        pr_debug("wait_for_completion return %ld\n", completion_rc);
  85
  86        if (completion_rc > 0) {
  87                switch (ndev->req_status) {
  88                case NCI_REQ_DONE:
  89                        rc = nci_to_errno(ndev->req_result);
  90                        break;
  91
  92                case NCI_REQ_CANCELED:
  93                        rc = -ndev->req_result;
  94                        break;
  95
  96                default:
  97                        rc = -ETIMEDOUT;
  98                        break;
  99                }
 100        } else {
 101                pr_err("wait_for_completion_interruptible_timeout failed %ld\n",
 102                       completion_rc);
 103
 104                rc = ((completion_rc == 0) ? (-ETIMEDOUT) : (completion_rc));
 105        }
 106
 107        ndev->req_status = ndev->req_result = 0;
 108
 109        return rc;
 110}
 111
 112static inline int nci_request(struct nci_dev *ndev,
 113                              void (*req)(struct nci_dev *ndev,
 114                                          unsigned long opt),
 115                              unsigned long opt, __u32 timeout)
 116{
 117        int rc;
 118
 119        if (!test_bit(NCI_UP, &ndev->flags))
 120                return -ENETDOWN;
 121
 122        /* Serialize all requests */
 123        mutex_lock(&ndev->req_lock);
 124        rc = __nci_request(ndev, req, opt, timeout);
 125        mutex_unlock(&ndev->req_lock);
 126
 127        return rc;
 128}
 129
 130static void nci_reset_req(struct nci_dev *ndev, unsigned long opt)
 131{
 132        struct nci_core_reset_cmd cmd;
 133
 134        cmd.reset_type = NCI_RESET_TYPE_RESET_CONFIG;
 135        nci_send_cmd(ndev, NCI_OP_CORE_RESET_CMD, 1, &cmd);
 136}
 137
 138static void nci_init_req(struct nci_dev *ndev, unsigned long opt)
 139{
 140        nci_send_cmd(ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);
 141}
 142
 143static void nci_init_complete_req(struct nci_dev *ndev, unsigned long opt)
 144{
 145        struct nci_rf_disc_map_cmd cmd;
 146        struct disc_map_config *cfg = cmd.mapping_configs;
 147        __u8 *num = &cmd.num_mapping_configs;
 148        int i;
 149
 150        /* set rf mapping configurations */
 151        *num = 0;
 152
 153        /* by default mapping is set to NCI_RF_INTERFACE_FRAME */
 154        for (i = 0; i < ndev->num_supported_rf_interfaces; i++) {
 155                if (ndev->supported_rf_interfaces[i] ==
 156                    NCI_RF_INTERFACE_ISO_DEP) {
 157                        cfg[*num].rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
 158                        cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
 159                                NCI_DISC_MAP_MODE_LISTEN;
 160                        cfg[*num].rf_interface = NCI_RF_INTERFACE_ISO_DEP;
 161                        (*num)++;
 162                } else if (ndev->supported_rf_interfaces[i] ==
 163                           NCI_RF_INTERFACE_NFC_DEP) {
 164                        cfg[*num].rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
 165                        cfg[*num].mode = NCI_DISC_MAP_MODE_POLL |
 166                                NCI_DISC_MAP_MODE_LISTEN;
 167                        cfg[*num].rf_interface = NCI_RF_INTERFACE_NFC_DEP;
 168                        (*num)++;
 169                }
 170
 171                if (*num == NCI_MAX_NUM_MAPPING_CONFIGS)
 172                        break;
 173        }
 174
 175        nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_MAP_CMD,
 176                     (1 + ((*num) * sizeof(struct disc_map_config))), &cmd);
 177}
 178
 179struct nci_set_config_param {
 180        __u8    id;
 181        size_t  len;
 182        __u8    *val;
 183};
 184
 185static void nci_set_config_req(struct nci_dev *ndev, unsigned long opt)
 186{
 187        struct nci_set_config_param *param = (struct nci_set_config_param *)opt;
 188        struct nci_core_set_config_cmd cmd;
 189
 190        BUG_ON(param->len > NCI_MAX_PARAM_LEN);
 191
 192        cmd.num_params = 1;
 193        cmd.param.id = param->id;
 194        cmd.param.len = param->len;
 195        memcpy(cmd.param.val, param->val, param->len);
 196
 197        nci_send_cmd(ndev, NCI_OP_CORE_SET_CONFIG_CMD, (3 + param->len), &cmd);
 198}
 199
 200static void nci_rf_discover_req(struct nci_dev *ndev, unsigned long opt)
 201{
 202        struct nci_rf_disc_cmd cmd;
 203        __u32 protocols = opt;
 204
 205        cmd.num_disc_configs = 0;
 206
 207        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 208            (protocols & NFC_PROTO_JEWEL_MASK ||
 209             protocols & NFC_PROTO_MIFARE_MASK ||
 210             protocols & NFC_PROTO_ISO14443_MASK ||
 211             protocols & NFC_PROTO_NFC_DEP_MASK)) {
 212                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 213                        NCI_NFC_A_PASSIVE_POLL_MODE;
 214                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 215                cmd.num_disc_configs++;
 216        }
 217
 218        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 219            (protocols & NFC_PROTO_ISO14443_B_MASK)) {
 220                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 221                        NCI_NFC_B_PASSIVE_POLL_MODE;
 222                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 223                cmd.num_disc_configs++;
 224        }
 225
 226        if ((cmd.num_disc_configs < NCI_MAX_NUM_RF_CONFIGS) &&
 227            (protocols & NFC_PROTO_FELICA_MASK ||
 228             protocols & NFC_PROTO_NFC_DEP_MASK)) {
 229                cmd.disc_configs[cmd.num_disc_configs].rf_tech_and_mode =
 230                        NCI_NFC_F_PASSIVE_POLL_MODE;
 231                cmd.disc_configs[cmd.num_disc_configs].frequency = 1;
 232                cmd.num_disc_configs++;
 233        }
 234
 235        nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_CMD,
 236                     (1 + (cmd.num_disc_configs * sizeof(struct disc_config))),
 237                     &cmd);
 238}
 239
 240struct nci_rf_discover_select_param {
 241        __u8    rf_discovery_id;
 242        __u8    rf_protocol;
 243};
 244
 245static void nci_rf_discover_select_req(struct nci_dev *ndev, unsigned long opt)
 246{
 247        struct nci_rf_discover_select_param *param =
 248                (struct nci_rf_discover_select_param *)opt;
 249        struct nci_rf_discover_select_cmd cmd;
 250
 251        cmd.rf_discovery_id = param->rf_discovery_id;
 252        cmd.rf_protocol = param->rf_protocol;
 253
 254        switch (cmd.rf_protocol) {
 255        case NCI_RF_PROTOCOL_ISO_DEP:
 256                cmd.rf_interface = NCI_RF_INTERFACE_ISO_DEP;
 257                break;
 258
 259        case NCI_RF_PROTOCOL_NFC_DEP:
 260                cmd.rf_interface = NCI_RF_INTERFACE_NFC_DEP;
 261                break;
 262
 263        default:
 264                cmd.rf_interface = NCI_RF_INTERFACE_FRAME;
 265                break;
 266        }
 267
 268        nci_send_cmd(ndev, NCI_OP_RF_DISCOVER_SELECT_CMD,
 269                     sizeof(struct nci_rf_discover_select_cmd), &cmd);
 270}
 271
 272static void nci_rf_deactivate_req(struct nci_dev *ndev, unsigned long opt)
 273{
 274        struct nci_rf_deactivate_cmd cmd;
 275
 276        cmd.type = NCI_DEACTIVATE_TYPE_IDLE_MODE;
 277
 278        nci_send_cmd(ndev, NCI_OP_RF_DEACTIVATE_CMD,
 279                     sizeof(struct nci_rf_deactivate_cmd), &cmd);
 280}
 281
 282static int nci_open_device(struct nci_dev *ndev)
 283{
 284        int rc = 0;
 285
 286        mutex_lock(&ndev->req_lock);
 287
 288        if (test_bit(NCI_UP, &ndev->flags)) {
 289                rc = -EALREADY;
 290                goto done;
 291        }
 292
 293        if (ndev->ops->open(ndev)) {
 294                rc = -EIO;
 295                goto done;
 296        }
 297
 298        atomic_set(&ndev->cmd_cnt, 1);
 299
 300        set_bit(NCI_INIT, &ndev->flags);
 301
 302        rc = __nci_request(ndev, nci_reset_req, 0,
 303                           msecs_to_jiffies(NCI_RESET_TIMEOUT));
 304
 305        if (!rc) {
 306                rc = __nci_request(ndev, nci_init_req, 0,
 307                                   msecs_to_jiffies(NCI_INIT_TIMEOUT));
 308        }
 309
 310        if (!rc) {
 311                rc = __nci_request(ndev, nci_init_complete_req, 0,
 312                                   msecs_to_jiffies(NCI_INIT_TIMEOUT));
 313        }
 314
 315        clear_bit(NCI_INIT, &ndev->flags);
 316
 317        if (!rc) {
 318                set_bit(NCI_UP, &ndev->flags);
 319                nci_clear_target_list(ndev);
 320                atomic_set(&ndev->state, NCI_IDLE);
 321        } else {
 322                /* Init failed, cleanup */
 323                skb_queue_purge(&ndev->cmd_q);
 324                skb_queue_purge(&ndev->rx_q);
 325                skb_queue_purge(&ndev->tx_q);
 326
 327                ndev->ops->close(ndev);
 328                ndev->flags = 0;
 329        }
 330
 331done:
 332        mutex_unlock(&ndev->req_lock);
 333        return rc;
 334}
 335
 336static int nci_close_device(struct nci_dev *ndev)
 337{
 338        nci_req_cancel(ndev, ENODEV);
 339        mutex_lock(&ndev->req_lock);
 340
 341        if (!test_and_clear_bit(NCI_UP, &ndev->flags)) {
 342                del_timer_sync(&ndev->cmd_timer);
 343                del_timer_sync(&ndev->data_timer);
 344                mutex_unlock(&ndev->req_lock);
 345                return 0;
 346        }
 347
 348        /* Drop RX and TX queues */
 349        skb_queue_purge(&ndev->rx_q);
 350        skb_queue_purge(&ndev->tx_q);
 351
 352        /* Flush RX and TX wq */
 353        flush_workqueue(ndev->rx_wq);
 354        flush_workqueue(ndev->tx_wq);
 355
 356        /* Reset device */
 357        skb_queue_purge(&ndev->cmd_q);
 358        atomic_set(&ndev->cmd_cnt, 1);
 359
 360        set_bit(NCI_INIT, &ndev->flags);
 361        __nci_request(ndev, nci_reset_req, 0,
 362                      msecs_to_jiffies(NCI_RESET_TIMEOUT));
 363        clear_bit(NCI_INIT, &ndev->flags);
 364
 365        /* Flush cmd wq */
 366        flush_workqueue(ndev->cmd_wq);
 367
 368        /* After this point our queues are empty
 369         * and no works are scheduled. */
 370        ndev->ops->close(ndev);
 371
 372        /* Clear flags */
 373        ndev->flags = 0;
 374
 375        mutex_unlock(&ndev->req_lock);
 376
 377        return 0;
 378}
 379
 380/* NCI command timer function */
 381static void nci_cmd_timer(unsigned long arg)
 382{
 383        struct nci_dev *ndev = (void *) arg;
 384
 385        atomic_set(&ndev->cmd_cnt, 1);
 386        queue_work(ndev->cmd_wq, &ndev->cmd_work);
 387}
 388
 389/* NCI data exchange timer function */
 390static void nci_data_timer(unsigned long arg)
 391{
 392        struct nci_dev *ndev = (void *) arg;
 393
 394        set_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
 395        queue_work(ndev->rx_wq, &ndev->rx_work);
 396}
 397
 398static int nci_dev_up(struct nfc_dev *nfc_dev)
 399{
 400        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 401
 402        return nci_open_device(ndev);
 403}
 404
 405static int nci_dev_down(struct nfc_dev *nfc_dev)
 406{
 407        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 408
 409        return nci_close_device(ndev);
 410}
 411
 412static int nci_set_local_general_bytes(struct nfc_dev *nfc_dev)
 413{
 414        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 415        struct nci_set_config_param param;
 416        __u8 local_gb[NFC_MAX_GT_LEN];
 417        int i;
 418
 419        param.val = nfc_get_local_general_bytes(nfc_dev, &param.len);
 420        if ((param.val == NULL) || (param.len == 0))
 421                return 0;
 422
 423        if (param.len > NFC_MAX_GT_LEN)
 424                return -EINVAL;
 425
 426        for (i = 0; i < param.len; i++)
 427                local_gb[param.len-1-i] = param.val[i];
 428
 429        param.id = NCI_PN_ATR_REQ_GEN_BYTES;
 430        param.val = local_gb;
 431
 432        return nci_request(ndev, nci_set_config_req, (unsigned long)&param,
 433                           msecs_to_jiffies(NCI_SET_CONFIG_TIMEOUT));
 434}
 435
 436static int nci_start_poll(struct nfc_dev *nfc_dev,
 437                          __u32 im_protocols, __u32 tm_protocols)
 438{
 439        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 440        int rc;
 441
 442        if ((atomic_read(&ndev->state) == NCI_DISCOVERY) ||
 443            (atomic_read(&ndev->state) == NCI_W4_ALL_DISCOVERIES)) {
 444                pr_err("unable to start poll, since poll is already active\n");
 445                return -EBUSY;
 446        }
 447
 448        if (ndev->target_active_prot) {
 449                pr_err("there is an active target\n");
 450                return -EBUSY;
 451        }
 452
 453        if ((atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) ||
 454            (atomic_read(&ndev->state) == NCI_POLL_ACTIVE)) {
 455                pr_debug("target active or w4 select, implicitly deactivate\n");
 456
 457                rc = nci_request(ndev, nci_rf_deactivate_req, 0,
 458                                 msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
 459                if (rc)
 460                        return -EBUSY;
 461        }
 462
 463        if (im_protocols & NFC_PROTO_NFC_DEP_MASK) {
 464                rc = nci_set_local_general_bytes(nfc_dev);
 465                if (rc) {
 466                        pr_err("failed to set local general bytes\n");
 467                        return rc;
 468                }
 469        }
 470
 471        rc = nci_request(ndev, nci_rf_discover_req, im_protocols,
 472                         msecs_to_jiffies(NCI_RF_DISC_TIMEOUT));
 473
 474        if (!rc)
 475                ndev->poll_prots = im_protocols;
 476
 477        return rc;
 478}
 479
 480static void nci_stop_poll(struct nfc_dev *nfc_dev)
 481{
 482        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 483
 484        if ((atomic_read(&ndev->state) != NCI_DISCOVERY) &&
 485            (atomic_read(&ndev->state) != NCI_W4_ALL_DISCOVERIES)) {
 486                pr_err("unable to stop poll, since poll is not active\n");
 487                return;
 488        }
 489
 490        nci_request(ndev, nci_rf_deactivate_req, 0,
 491                    msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
 492}
 493
 494static int nci_activate_target(struct nfc_dev *nfc_dev,
 495                               struct nfc_target *target, __u32 protocol)
 496{
 497        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 498        struct nci_rf_discover_select_param param;
 499        struct nfc_target *nci_target = NULL;
 500        int i;
 501        int rc = 0;
 502
 503        pr_debug("target_idx %d, protocol 0x%x\n", target->idx, protocol);
 504
 505        if ((atomic_read(&ndev->state) != NCI_W4_HOST_SELECT) &&
 506            (atomic_read(&ndev->state) != NCI_POLL_ACTIVE)) {
 507                pr_err("there is no available target to activate\n");
 508                return -EINVAL;
 509        }
 510
 511        if (ndev->target_active_prot) {
 512                pr_err("there is already an active target\n");
 513                return -EBUSY;
 514        }
 515
 516        for (i = 0; i < ndev->n_targets; i++) {
 517                if (ndev->targets[i].idx == target->idx) {
 518                        nci_target = &ndev->targets[i];
 519                        break;
 520                }
 521        }
 522
 523        if (!nci_target) {
 524                pr_err("unable to find the selected target\n");
 525                return -EINVAL;
 526        }
 527
 528        if (!(nci_target->supported_protocols & (1 << protocol))) {
 529                pr_err("target does not support the requested protocol 0x%x\n",
 530                       protocol);
 531                return -EINVAL;
 532        }
 533
 534        if (atomic_read(&ndev->state) == NCI_W4_HOST_SELECT) {
 535                param.rf_discovery_id = nci_target->logical_idx;
 536
 537                if (protocol == NFC_PROTO_JEWEL)
 538                        param.rf_protocol = NCI_RF_PROTOCOL_T1T;
 539                else if (protocol == NFC_PROTO_MIFARE)
 540                        param.rf_protocol = NCI_RF_PROTOCOL_T2T;
 541                else if (protocol == NFC_PROTO_FELICA)
 542                        param.rf_protocol = NCI_RF_PROTOCOL_T3T;
 543                else if (protocol == NFC_PROTO_ISO14443 ||
 544                         protocol == NFC_PROTO_ISO14443_B)
 545                        param.rf_protocol = NCI_RF_PROTOCOL_ISO_DEP;
 546                else
 547                        param.rf_protocol = NCI_RF_PROTOCOL_NFC_DEP;
 548
 549                rc = nci_request(ndev, nci_rf_discover_select_req,
 550                                 (unsigned long)&param,
 551                                 msecs_to_jiffies(NCI_RF_DISC_SELECT_TIMEOUT));
 552        }
 553
 554        if (!rc)
 555                ndev->target_active_prot = protocol;
 556
 557        return rc;
 558}
 559
 560static void nci_deactivate_target(struct nfc_dev *nfc_dev,
 561                                  struct nfc_target *target)
 562{
 563        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 564
 565        pr_debug("entry\n");
 566
 567        if (!ndev->target_active_prot) {
 568                pr_err("unable to deactivate target, no active target\n");
 569                return;
 570        }
 571
 572        ndev->target_active_prot = 0;
 573
 574        if (atomic_read(&ndev->state) == NCI_POLL_ACTIVE) {
 575                nci_request(ndev, nci_rf_deactivate_req, 0,
 576                            msecs_to_jiffies(NCI_RF_DEACTIVATE_TIMEOUT));
 577        }
 578}
 579
 580static int nci_dep_link_up(struct nfc_dev *nfc_dev, struct nfc_target *target,
 581                           __u8 comm_mode, __u8 *gb, size_t gb_len)
 582{
 583        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 584        int rc;
 585
 586        pr_debug("target_idx %d, comm_mode %d\n", target->idx, comm_mode);
 587
 588        rc = nci_activate_target(nfc_dev, target, NFC_PROTO_NFC_DEP);
 589        if (rc)
 590                return rc;
 591
 592        rc = nfc_set_remote_general_bytes(nfc_dev, ndev->remote_gb,
 593                                          ndev->remote_gb_len);
 594        if (!rc)
 595                rc = nfc_dep_link_is_up(nfc_dev, target->idx, NFC_COMM_PASSIVE,
 596                                        NFC_RF_INITIATOR);
 597
 598        return rc;
 599}
 600
 601static int nci_dep_link_down(struct nfc_dev *nfc_dev)
 602{
 603        pr_debug("entry\n");
 604
 605        nci_deactivate_target(nfc_dev, NULL);
 606
 607        return 0;
 608}
 609
 610
 611static int nci_transceive(struct nfc_dev *nfc_dev, struct nfc_target *target,
 612                          struct sk_buff *skb,
 613                          data_exchange_cb_t cb, void *cb_context)
 614{
 615        struct nci_dev *ndev = nfc_get_drvdata(nfc_dev);
 616        int rc;
 617
 618        pr_debug("target_idx %d, len %d\n", target->idx, skb->len);
 619
 620        if (!ndev->target_active_prot) {
 621                pr_err("unable to exchange data, no active target\n");
 622                return -EINVAL;
 623        }
 624
 625        if (test_and_set_bit(NCI_DATA_EXCHANGE, &ndev->flags))
 626                return -EBUSY;
 627
 628        /* store cb and context to be used on receiving data */
 629        ndev->data_exchange_cb = cb;
 630        ndev->data_exchange_cb_context = cb_context;
 631
 632        rc = nci_send_data(ndev, NCI_STATIC_RF_CONN_ID, skb);
 633        if (rc)
 634                clear_bit(NCI_DATA_EXCHANGE, &ndev->flags);
 635
 636        return rc;
 637}
 638
 639static struct nfc_ops nci_nfc_ops = {
 640        .dev_up = nci_dev_up,
 641        .dev_down = nci_dev_down,
 642        .start_poll = nci_start_poll,
 643        .stop_poll = nci_stop_poll,
 644        .dep_link_up = nci_dep_link_up,
 645        .dep_link_down = nci_dep_link_down,
 646        .activate_target = nci_activate_target,
 647        .deactivate_target = nci_deactivate_target,
 648        .im_transceive = nci_transceive,
 649};
 650
 651/* ---- Interface to NCI drivers ---- */
 652
 653/**
 654 * nci_allocate_device - allocate a new nci device
 655 *
 656 * @ops: device operations
 657 * @supported_protocols: NFC protocols supported by the device
 658 */
 659struct nci_dev *nci_allocate_device(struct nci_ops *ops,
 660                                    __u32 supported_protocols,
 661                                    __u32 supported_se,
 662                                    int tx_headroom, int tx_tailroom)
 663{
 664        struct nci_dev *ndev;
 665
 666        pr_debug("supported_protocols 0x%x\n", supported_protocols);
 667
 668        if (!ops->open || !ops->close || !ops->send)
 669                return NULL;
 670
 671        if (!supported_protocols)
 672                return NULL;
 673
 674        ndev = kzalloc(sizeof(struct nci_dev), GFP_KERNEL);
 675        if (!ndev)
 676                return NULL;
 677
 678        ndev->ops = ops;
 679        ndev->tx_headroom = tx_headroom;
 680        ndev->tx_tailroom = tx_tailroom;
 681
 682        ndev->nfc_dev = nfc_allocate_device(&nci_nfc_ops,
 683                                            supported_protocols,
 684                                            supported_se,
 685                                            tx_headroom + NCI_DATA_HDR_SIZE,
 686                                            tx_tailroom);
 687        if (!ndev->nfc_dev)
 688                goto free_exit;
 689
 690        nfc_set_drvdata(ndev->nfc_dev, ndev);
 691
 692        return ndev;
 693
 694free_exit:
 695        kfree(ndev);
 696        return NULL;
 697}
 698EXPORT_SYMBOL(nci_allocate_device);
 699
 700/**
 701 * nci_free_device - deallocate nci device
 702 *
 703 * @ndev: The nci device to deallocate
 704 */
 705void nci_free_device(struct nci_dev *ndev)
 706{
 707        nfc_free_device(ndev->nfc_dev);
 708        kfree(ndev);
 709}
 710EXPORT_SYMBOL(nci_free_device);
 711
 712/**
 713 * nci_register_device - register a nci device in the nfc subsystem
 714 *
 715 * @dev: The nci device to register
 716 */
 717int nci_register_device(struct nci_dev *ndev)
 718{
 719        int rc;
 720        struct device *dev = &ndev->nfc_dev->dev;
 721        char name[32];
 722
 723        rc = nfc_register_device(ndev->nfc_dev);
 724        if (rc)
 725                goto exit;
 726
 727        ndev->flags = 0;
 728
 729        INIT_WORK(&ndev->cmd_work, nci_cmd_work);
 730        snprintf(name, sizeof(name), "%s_nci_cmd_wq", dev_name(dev));
 731        ndev->cmd_wq = create_singlethread_workqueue(name);
 732        if (!ndev->cmd_wq) {
 733                rc = -ENOMEM;
 734                goto unreg_exit;
 735        }
 736
 737        INIT_WORK(&ndev->rx_work, nci_rx_work);
 738        snprintf(name, sizeof(name), "%s_nci_rx_wq", dev_name(dev));
 739        ndev->rx_wq = create_singlethread_workqueue(name);
 740        if (!ndev->rx_wq) {
 741                rc = -ENOMEM;
 742                goto destroy_cmd_wq_exit;
 743        }
 744
 745        INIT_WORK(&ndev->tx_work, nci_tx_work);
 746        snprintf(name, sizeof(name), "%s_nci_tx_wq", dev_name(dev));
 747        ndev->tx_wq = create_singlethread_workqueue(name);
 748        if (!ndev->tx_wq) {
 749                rc = -ENOMEM;
 750                goto destroy_rx_wq_exit;
 751        }
 752
 753        skb_queue_head_init(&ndev->cmd_q);
 754        skb_queue_head_init(&ndev->rx_q);
 755        skb_queue_head_init(&ndev->tx_q);
 756
 757        setup_timer(&ndev->cmd_timer, nci_cmd_timer,
 758                    (unsigned long) ndev);
 759        setup_timer(&ndev->data_timer, nci_data_timer,
 760                    (unsigned long) ndev);
 761
 762        mutex_init(&ndev->req_lock);
 763
 764        goto exit;
 765
 766destroy_rx_wq_exit:
 767        destroy_workqueue(ndev->rx_wq);
 768
 769destroy_cmd_wq_exit:
 770        destroy_workqueue(ndev->cmd_wq);
 771
 772unreg_exit:
 773        nfc_unregister_device(ndev->nfc_dev);
 774
 775exit:
 776        return rc;
 777}
 778EXPORT_SYMBOL(nci_register_device);
 779
 780/**
 781 * nci_unregister_device - unregister a nci device in the nfc subsystem
 782 *
 783 * @dev: The nci device to unregister
 784 */
 785void nci_unregister_device(struct nci_dev *ndev)
 786{
 787        nci_close_device(ndev);
 788
 789        destroy_workqueue(ndev->cmd_wq);
 790        destroy_workqueue(ndev->rx_wq);
 791        destroy_workqueue(ndev->tx_wq);
 792
 793        nfc_unregister_device(ndev->nfc_dev);
 794}
 795EXPORT_SYMBOL(nci_unregister_device);
 796
 797/**
 798 * nci_recv_frame - receive frame from NCI drivers
 799 *
 800 * @skb: The sk_buff to receive
 801 */
 802int nci_recv_frame(struct sk_buff *skb)
 803{
 804        struct nci_dev *ndev = (struct nci_dev *) skb->dev;
 805
 806        pr_debug("len %d\n", skb->len);
 807
 808        if (!ndev || (!test_bit(NCI_UP, &ndev->flags) &&
 809            !test_bit(NCI_INIT, &ndev->flags))) {
 810                kfree_skb(skb);
 811                return -ENXIO;
 812        }
 813
 814        /* Queue frame for rx worker thread */
 815        skb_queue_tail(&ndev->rx_q, skb);
 816        queue_work(ndev->rx_wq, &ndev->rx_work);
 817
 818        return 0;
 819}
 820EXPORT_SYMBOL(nci_recv_frame);
 821
 822static int nci_send_frame(struct sk_buff *skb)
 823{
 824        struct nci_dev *ndev = (struct nci_dev *) skb->dev;
 825
 826        pr_debug("len %d\n", skb->len);
 827
 828        if (!ndev) {
 829                kfree_skb(skb);
 830                return -ENODEV;
 831        }
 832
 833        /* Get rid of skb owner, prior to sending to the driver. */
 834        skb_orphan(skb);
 835
 836        return ndev->ops->send(skb);
 837}
 838
 839/* Send NCI command */
 840int nci_send_cmd(struct nci_dev *ndev, __u16 opcode, __u8 plen, void *payload)
 841{
 842        struct nci_ctrl_hdr *hdr;
 843        struct sk_buff *skb;
 844
 845        pr_debug("opcode 0x%x, plen %d\n", opcode, plen);
 846
 847        skb = nci_skb_alloc(ndev, (NCI_CTRL_HDR_SIZE + plen), GFP_KERNEL);
 848        if (!skb) {
 849                pr_err("no memory for command\n");
 850                return -ENOMEM;
 851        }
 852
 853        hdr = (struct nci_ctrl_hdr *) skb_put(skb, NCI_CTRL_HDR_SIZE);
 854        hdr->gid = nci_opcode_gid(opcode);
 855        hdr->oid = nci_opcode_oid(opcode);
 856        hdr->plen = plen;
 857
 858        nci_mt_set((__u8 *)hdr, NCI_MT_CMD_PKT);
 859        nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);
 860
 861        if (plen)
 862                memcpy(skb_put(skb, plen), payload, plen);
 863
 864        skb->dev = (void *) ndev;
 865
 866        skb_queue_tail(&ndev->cmd_q, skb);
 867        queue_work(ndev->cmd_wq, &ndev->cmd_work);
 868
 869        return 0;
 870}
 871
 872/* ---- NCI TX Data worker thread ---- */
 873
 874static void nci_tx_work(struct work_struct *work)
 875{
 876        struct nci_dev *ndev = container_of(work, struct nci_dev, tx_work);
 877        struct sk_buff *skb;
 878
 879        pr_debug("credits_cnt %d\n", atomic_read(&ndev->credits_cnt));
 880
 881        /* Send queued tx data */
 882        while (atomic_read(&ndev->credits_cnt)) {
 883                skb = skb_dequeue(&ndev->tx_q);
 884                if (!skb)
 885                        return;
 886
 887                /* Check if data flow control is used */
 888                if (atomic_read(&ndev->credits_cnt) !=
 889                    NCI_DATA_FLOW_CONTROL_NOT_USED)
 890                        atomic_dec(&ndev->credits_cnt);
 891
 892                pr_debug("NCI TX: MT=data, PBF=%d, conn_id=%d, plen=%d\n",
 893                         nci_pbf(skb->data),
 894                         nci_conn_id(skb->data),
 895                         nci_plen(skb->data));
 896
 897                nci_send_frame(skb);
 898
 899                mod_timer(&ndev->data_timer,
 900                          jiffies + msecs_to_jiffies(NCI_DATA_TIMEOUT));
 901        }
 902}
 903
 904/* ----- NCI RX worker thread (data & control) ----- */
 905
 906static void nci_rx_work(struct work_struct *work)
 907{
 908        struct nci_dev *ndev = container_of(work, struct nci_dev, rx_work);
 909        struct sk_buff *skb;
 910
 911        while ((skb = skb_dequeue(&ndev->rx_q))) {
 912                /* Process frame */
 913                switch (nci_mt(skb->data)) {
 914                case NCI_MT_RSP_PKT:
 915                        nci_rsp_packet(ndev, skb);
 916                        break;
 917
 918                case NCI_MT_NTF_PKT:
 919                        nci_ntf_packet(ndev, skb);
 920                        break;
 921
 922                case NCI_MT_DATA_PKT:
 923                        nci_rx_data_packet(ndev, skb);
 924                        break;
 925
 926                default:
 927                        pr_err("unknown MT 0x%x\n", nci_mt(skb->data));
 928                        kfree_skb(skb);
 929                        break;
 930                }
 931        }
 932
 933        /* check if a data exchange timout has occurred */
 934        if (test_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags)) {
 935                /* complete the data exchange transaction, if exists */
 936                if (test_bit(NCI_DATA_EXCHANGE, &ndev->flags))
 937                        nci_data_exchange_complete(ndev, NULL, -ETIMEDOUT);
 938
 939                clear_bit(NCI_DATA_EXCHANGE_TO, &ndev->flags);
 940        }
 941}
 942
 943/* ----- NCI TX CMD worker thread ----- */
 944
 945static void nci_cmd_work(struct work_struct *work)
 946{
 947        struct nci_dev *ndev = container_of(work, struct nci_dev, cmd_work);
 948        struct sk_buff *skb;
 949
 950        pr_debug("cmd_cnt %d\n", atomic_read(&ndev->cmd_cnt));
 951
 952        /* Send queued command */
 953        if (atomic_read(&ndev->cmd_cnt)) {
 954                skb = skb_dequeue(&ndev->cmd_q);
 955                if (!skb)
 956                        return;
 957
 958                atomic_dec(&ndev->cmd_cnt);
 959
 960                pr_debug("NCI TX: MT=cmd, PBF=%d, GID=0x%x, OID=0x%x, plen=%d\n",
 961                         nci_pbf(skb->data),
 962                         nci_opcode_gid(nci_opcode(skb->data)),
 963                         nci_opcode_oid(nci_opcode(skb->data)),
 964                         nci_plen(skb->data));
 965
 966                nci_send_frame(skb);
 967
 968                mod_timer(&ndev->cmd_timer,
 969                          jiffies + msecs_to_jiffies(NCI_CMD_TIMEOUT));
 970        }
 971}
 972
 973MODULE_LICENSE("GPL");
 974