linux/net/nfc/digital_dep.c
<<
>>
Prefs
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * NFC Digital Protocol stack
   4 * Copyright (c) 2013, Intel Corporation.
   5 */
   6
   7#define pr_fmt(fmt) "digital: %s: " fmt, __func__
   8
   9#include "digital.h"
  10
  11#define DIGITAL_NFC_DEP_N_RETRY_NACK    2
  12#define DIGITAL_NFC_DEP_N_RETRY_ATN     2
  13
  14#define DIGITAL_NFC_DEP_FRAME_DIR_OUT 0xD4
  15#define DIGITAL_NFC_DEP_FRAME_DIR_IN  0xD5
  16
  17#define DIGITAL_NFC_DEP_NFCA_SOD_SB   0xF0
  18
  19#define DIGITAL_CMD_ATR_REQ 0x00
  20#define DIGITAL_CMD_ATR_RES 0x01
  21#define DIGITAL_CMD_PSL_REQ 0x04
  22#define DIGITAL_CMD_PSL_RES 0x05
  23#define DIGITAL_CMD_DEP_REQ 0x06
  24#define DIGITAL_CMD_DEP_RES 0x07
  25
  26#define DIGITAL_ATR_REQ_MIN_SIZE 16
  27#define DIGITAL_ATR_REQ_MAX_SIZE 64
  28
  29#define DIGITAL_ATR_RES_TO_WT(s)        ((s) & 0xF)
  30
  31#define DIGITAL_DID_MAX 14
  32
  33#define DIGITAL_PAYLOAD_SIZE_MAX        254
  34#define DIGITAL_PAYLOAD_BITS_TO_PP(s)   (((s) & 0x3) << 4)
  35#define DIGITAL_PAYLOAD_PP_TO_BITS(s)   (((s) >> 4) & 0x3)
  36#define DIGITAL_PAYLOAD_BITS_TO_FSL(s)  ((s) & 0x3)
  37#define DIGITAL_PAYLOAD_FSL_TO_BITS(s)  ((s) & 0x3)
  38
  39#define DIGITAL_GB_BIT  0x02
  40
  41#define DIGITAL_NFC_DEP_REQ_RES_HEADROOM        2 /* SoD: [SB (NFC-A)] + LEN */
  42#define DIGITAL_NFC_DEP_REQ_RES_TAILROOM        2 /* EoD: 2-byte CRC */
  43
  44#define DIGITAL_NFC_DEP_PFB_TYPE(pfb) ((pfb) & 0xE0)
  45
  46#define DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT 0x10
  47#define DIGITAL_NFC_DEP_PFB_MI_BIT      0x10
  48#define DIGITAL_NFC_DEP_PFB_NACK_BIT    0x10
  49#define DIGITAL_NFC_DEP_PFB_DID_BIT     0x04
  50
  51#define DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
  52                                ((pfb) & DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT)
  53#define DIGITAL_NFC_DEP_MI_BIT_SET(pfb)  ((pfb) & DIGITAL_NFC_DEP_PFB_MI_BIT)
  54#define DIGITAL_NFC_DEP_NACK_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_NACK_BIT)
  55#define DIGITAL_NFC_DEP_NAD_BIT_SET(pfb) ((pfb) & 0x08)
  56#define DIGITAL_NFC_DEP_DID_BIT_SET(pfb) ((pfb) & DIGITAL_NFC_DEP_PFB_DID_BIT)
  57#define DIGITAL_NFC_DEP_PFB_PNI(pfb)     ((pfb) & 0x03)
  58
  59#define DIGITAL_NFC_DEP_RTOX_VALUE(data) ((data) & 0x3F)
  60#define DIGITAL_NFC_DEP_RTOX_MAX         59
  61
  62#define DIGITAL_NFC_DEP_PFB_I_PDU          0x00
  63#define DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU   0x40
  64#define DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU 0x80
  65
  66struct digital_atr_req {
  67        u8 dir;
  68        u8 cmd;
  69        u8 nfcid3[10];
  70        u8 did;
  71        u8 bs;
  72        u8 br;
  73        u8 pp;
  74        u8 gb[0];
  75} __packed;
  76
  77struct digital_atr_res {
  78        u8 dir;
  79        u8 cmd;
  80        u8 nfcid3[10];
  81        u8 did;
  82        u8 bs;
  83        u8 br;
  84        u8 to;
  85        u8 pp;
  86        u8 gb[0];
  87} __packed;
  88
  89struct digital_psl_req {
  90        u8 dir;
  91        u8 cmd;
  92        u8 did;
  93        u8 brs;
  94        u8 fsl;
  95} __packed;
  96
  97struct digital_psl_res {
  98        u8 dir;
  99        u8 cmd;
 100        u8 did;
 101} __packed;
 102
 103struct digital_dep_req_res {
 104        u8 dir;
 105        u8 cmd;
 106        u8 pfb;
 107} __packed;
 108
 109static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 110                                    struct sk_buff *resp);
 111static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
 112                                    struct sk_buff *resp);
 113
 114static const u8 digital_payload_bits_map[4] = {
 115        [0] = 64,
 116        [1] = 128,
 117        [2] = 192,
 118        [3] = 254
 119};
 120
 121/* Response Waiting Time for ATR_RES PDU in ms
 122 *
 123 * RWT(ATR_RES) = RWT(nfcdep,activation) + dRWT(nfcdep) + dT(nfcdep,initiator)
 124 *
 125 * with:
 126 *  RWT(nfcdep,activation) = 4096 * 2^12 / f(c) s
 127 *  dRWT(nfcdep) = 16 / f(c) s
 128 *  dT(nfcdep,initiator) = 100 ms
 129 *  f(c) = 13560000 Hz
 130 */
 131#define DIGITAL_ATR_RES_RWT 1337
 132
 133/* Response Waiting Time for other DEP PDUs in ms
 134 *
 135 * max_rwt = rwt + dRWT(nfcdep) + dT(nfcdep,initiator)
 136 *
 137 * with:
 138 *  rwt = (256 * 16 / f(c)) * 2^wt s
 139 *  dRWT(nfcdep) = 16 / f(c) s
 140 *  dT(nfcdep,initiator) = 100 ms
 141 *  f(c) = 13560000 Hz
 142 *  0 <= wt <= 14 (given by the target by the TO field of ATR_RES response)
 143 */
 144#define DIGITAL_NFC_DEP_IN_MAX_WT 14
 145#define DIGITAL_NFC_DEP_TG_MAX_WT 14
 146static const u16 digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT + 1] = {
 147        100,  101,  101,  102,  105,
 148        110,  119,  139,  177,  255,
 149        409,  719, 1337, 2575, 5049,
 150};
 151
 152static u8 digital_payload_bits_to_size(u8 payload_bits)
 153{
 154        if (payload_bits >= ARRAY_SIZE(digital_payload_bits_map))
 155                return 0;
 156
 157        return digital_payload_bits_map[payload_bits];
 158}
 159
 160static u8 digital_payload_size_to_bits(u8 payload_size)
 161{
 162        int i;
 163
 164        for (i = 0; i < ARRAY_SIZE(digital_payload_bits_map); i++)
 165                if (digital_payload_bits_map[i] == payload_size)
 166                        return i;
 167
 168        return 0xff;
 169}
 170
 171static void digital_skb_push_dep_sod(struct nfc_digital_dev *ddev,
 172                                     struct sk_buff *skb)
 173{
 174        skb_push(skb, sizeof(u8));
 175
 176        skb->data[0] = skb->len;
 177
 178        if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)
 179                *(u8 *)skb_push(skb, sizeof(u8)) = DIGITAL_NFC_DEP_NFCA_SOD_SB;
 180}
 181
 182static int digital_skb_pull_dep_sod(struct nfc_digital_dev *ddev,
 183                                    struct sk_buff *skb)
 184{
 185        u8 size;
 186
 187        if (skb->len < 2)
 188                return -EIO;
 189
 190        if (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)
 191                skb_pull(skb, sizeof(u8));
 192
 193        size = skb->data[0];
 194        if (size != skb->len)
 195                return -EIO;
 196
 197        skb_pull(skb, sizeof(u8));
 198
 199        return 0;
 200}
 201
 202static struct sk_buff *
 203digital_send_dep_data_prep(struct nfc_digital_dev *ddev, struct sk_buff *skb,
 204                           struct digital_dep_req_res *dep_req_res,
 205                           struct digital_data_exch *data_exch)
 206{
 207        struct sk_buff *new_skb;
 208
 209        if (skb->len > ddev->remote_payload_max) {
 210                dep_req_res->pfb |= DIGITAL_NFC_DEP_PFB_MI_BIT;
 211
 212                new_skb = digital_skb_alloc(ddev, ddev->remote_payload_max);
 213                if (!new_skb) {
 214                        kfree_skb(ddev->chaining_skb);
 215                        ddev->chaining_skb = NULL;
 216
 217                        return ERR_PTR(-ENOMEM);
 218                }
 219
 220                skb_put_data(new_skb, skb->data, ddev->remote_payload_max);
 221                skb_pull(skb, ddev->remote_payload_max);
 222
 223                ddev->chaining_skb = skb;
 224                ddev->data_exch = data_exch;
 225        } else {
 226                ddev->chaining_skb = NULL;
 227                new_skb = skb;
 228        }
 229
 230        return new_skb;
 231}
 232
 233static struct sk_buff *
 234digital_recv_dep_data_gather(struct nfc_digital_dev *ddev, u8 pfb,
 235                             struct sk_buff *resp,
 236                             int (*send_ack)(struct nfc_digital_dev *ddev,
 237                                             struct digital_data_exch
 238                                                             *data_exch),
 239                             struct digital_data_exch *data_exch)
 240{
 241        struct sk_buff *new_skb;
 242        int rc;
 243
 244        if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb) && (!ddev->chaining_skb)) {
 245                ddev->chaining_skb =
 246                        nfc_alloc_recv_skb(8 * ddev->local_payload_max,
 247                                           GFP_KERNEL);
 248                if (!ddev->chaining_skb) {
 249                        rc = -ENOMEM;
 250                        goto error;
 251                }
 252        }
 253
 254        if (ddev->chaining_skb) {
 255                if (resp->len > skb_tailroom(ddev->chaining_skb)) {
 256                        new_skb = skb_copy_expand(ddev->chaining_skb,
 257                                                  skb_headroom(
 258                                                          ddev->chaining_skb),
 259                                                  8 * ddev->local_payload_max,
 260                                                  GFP_KERNEL);
 261                        if (!new_skb) {
 262                                rc = -ENOMEM;
 263                                goto error;
 264                        }
 265
 266                        kfree_skb(ddev->chaining_skb);
 267                        ddev->chaining_skb = new_skb;
 268                }
 269
 270                skb_put_data(ddev->chaining_skb, resp->data, resp->len);
 271
 272                kfree_skb(resp);
 273                resp = NULL;
 274
 275                if (DIGITAL_NFC_DEP_MI_BIT_SET(pfb)) {
 276                        rc = send_ack(ddev, data_exch);
 277                        if (rc)
 278                                goto error;
 279
 280                        return NULL;
 281                }
 282
 283                resp = ddev->chaining_skb;
 284                ddev->chaining_skb = NULL;
 285        }
 286
 287        return resp;
 288
 289error:
 290        kfree_skb(resp);
 291
 292        kfree_skb(ddev->chaining_skb);
 293        ddev->chaining_skb = NULL;
 294
 295        return ERR_PTR(rc);
 296}
 297
 298static void digital_in_recv_psl_res(struct nfc_digital_dev *ddev, void *arg,
 299                                    struct sk_buff *resp)
 300{
 301        struct nfc_target *target = arg;
 302        struct digital_psl_res *psl_res;
 303        int rc;
 304
 305        if (IS_ERR(resp)) {
 306                rc = PTR_ERR(resp);
 307                resp = NULL;
 308                goto exit;
 309        }
 310
 311        rc = ddev->skb_check_crc(resp);
 312        if (rc) {
 313                PROTOCOL_ERR("14.4.1.6");
 314                goto exit;
 315        }
 316
 317        rc = digital_skb_pull_dep_sod(ddev, resp);
 318        if (rc) {
 319                PROTOCOL_ERR("14.4.1.2");
 320                goto exit;
 321        }
 322
 323        psl_res = (struct digital_psl_res *)resp->data;
 324
 325        if ((resp->len != sizeof(*psl_res)) ||
 326            (psl_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN) ||
 327            (psl_res->cmd != DIGITAL_CMD_PSL_RES)) {
 328                rc = -EIO;
 329                goto exit;
 330        }
 331
 332        rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH,
 333                                     NFC_DIGITAL_RF_TECH_424F);
 334        if (rc)
 335                goto exit;
 336
 337        rc = digital_in_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
 338                                     NFC_DIGITAL_FRAMING_NFCF_NFC_DEP);
 339        if (rc)
 340                goto exit;
 341
 342        if (!DIGITAL_DRV_CAPS_IN_CRC(ddev) &&
 343            (ddev->curr_rf_tech == NFC_DIGITAL_RF_TECH_106A)) {
 344                ddev->skb_add_crc = digital_skb_add_crc_f;
 345                ddev->skb_check_crc = digital_skb_check_crc_f;
 346        }
 347
 348        ddev->curr_rf_tech = NFC_DIGITAL_RF_TECH_424F;
 349
 350        nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE,
 351                           NFC_RF_INITIATOR);
 352
 353        ddev->curr_nfc_dep_pni = 0;
 354
 355exit:
 356        dev_kfree_skb(resp);
 357
 358        if (rc)
 359                ddev->curr_protocol = 0;
 360}
 361
 362static int digital_in_send_psl_req(struct nfc_digital_dev *ddev,
 363                                   struct nfc_target *target)
 364{
 365        struct sk_buff *skb;
 366        struct digital_psl_req *psl_req;
 367        int rc;
 368        u8 payload_size, payload_bits;
 369
 370        skb = digital_skb_alloc(ddev, sizeof(*psl_req));
 371        if (!skb)
 372                return -ENOMEM;
 373
 374        skb_put(skb, sizeof(*psl_req));
 375
 376        psl_req = (struct digital_psl_req *)skb->data;
 377
 378        psl_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 379        psl_req->cmd = DIGITAL_CMD_PSL_REQ;
 380        psl_req->did = 0;
 381        psl_req->brs = (0x2 << 3) | 0x2; /* 424F both directions */
 382
 383        payload_size = min(ddev->local_payload_max, ddev->remote_payload_max);
 384        payload_bits = digital_payload_size_to_bits(payload_size);
 385        psl_req->fsl = DIGITAL_PAYLOAD_BITS_TO_FSL(payload_bits);
 386
 387        ddev->local_payload_max = payload_size;
 388        ddev->remote_payload_max = payload_size;
 389
 390        digital_skb_push_dep_sod(ddev, skb);
 391
 392        ddev->skb_add_crc(skb);
 393
 394        rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 395                                 digital_in_recv_psl_res, target);
 396        if (rc)
 397                kfree_skb(skb);
 398
 399        return rc;
 400}
 401
 402static void digital_in_recv_atr_res(struct nfc_digital_dev *ddev, void *arg,
 403                                 struct sk_buff *resp)
 404{
 405        struct nfc_target *target = arg;
 406        struct digital_atr_res *atr_res;
 407        u8 gb_len, payload_bits;
 408        u8 wt;
 409        int rc;
 410
 411        if (IS_ERR(resp)) {
 412                rc = PTR_ERR(resp);
 413                resp = NULL;
 414                goto exit;
 415        }
 416
 417        rc = ddev->skb_check_crc(resp);
 418        if (rc) {
 419                PROTOCOL_ERR("14.4.1.6");
 420                goto exit;
 421        }
 422
 423        rc = digital_skb_pull_dep_sod(ddev, resp);
 424        if (rc) {
 425                PROTOCOL_ERR("14.4.1.2");
 426                goto exit;
 427        }
 428
 429        if (resp->len < sizeof(struct digital_atr_res)) {
 430                rc = -EIO;
 431                goto exit;
 432        }
 433
 434        gb_len = resp->len - sizeof(struct digital_atr_res);
 435
 436        atr_res = (struct digital_atr_res *)resp->data;
 437
 438        wt = DIGITAL_ATR_RES_TO_WT(atr_res->to);
 439        if (wt > DIGITAL_NFC_DEP_IN_MAX_WT)
 440                wt = DIGITAL_NFC_DEP_IN_MAX_WT;
 441        ddev->dep_rwt = digital_rwt_map[wt];
 442
 443        payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_res->pp);
 444        ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
 445
 446        if (!ddev->remote_payload_max) {
 447                rc = -EINVAL;
 448                goto exit;
 449        }
 450
 451        rc = nfc_set_remote_general_bytes(ddev->nfc_dev, atr_res->gb, gb_len);
 452        if (rc)
 453                goto exit;
 454
 455        if ((ddev->protocols & NFC_PROTO_FELICA_MASK) &&
 456            (ddev->curr_rf_tech != NFC_DIGITAL_RF_TECH_424F)) {
 457                rc = digital_in_send_psl_req(ddev, target);
 458                if (!rc)
 459                        goto exit;
 460        }
 461
 462        rc = nfc_dep_link_is_up(ddev->nfc_dev, target->idx, NFC_COMM_ACTIVE,
 463                                NFC_RF_INITIATOR);
 464
 465        ddev->curr_nfc_dep_pni = 0;
 466
 467exit:
 468        dev_kfree_skb(resp);
 469
 470        if (rc)
 471                ddev->curr_protocol = 0;
 472}
 473
 474int digital_in_send_atr_req(struct nfc_digital_dev *ddev,
 475                            struct nfc_target *target, __u8 comm_mode, __u8 *gb,
 476                            size_t gb_len)
 477{
 478        struct sk_buff *skb;
 479        struct digital_atr_req *atr_req;
 480        uint size;
 481        int rc;
 482        u8 payload_bits;
 483
 484        size = DIGITAL_ATR_REQ_MIN_SIZE + gb_len;
 485
 486        if (size > DIGITAL_ATR_REQ_MAX_SIZE) {
 487                PROTOCOL_ERR("14.6.1.1");
 488                return -EINVAL;
 489        }
 490
 491        skb = digital_skb_alloc(ddev, size);
 492        if (!skb)
 493                return -ENOMEM;
 494
 495        skb_put(skb, sizeof(struct digital_atr_req));
 496
 497        atr_req = (struct digital_atr_req *)skb->data;
 498        memset(atr_req, 0, sizeof(struct digital_atr_req));
 499
 500        atr_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 501        atr_req->cmd = DIGITAL_CMD_ATR_REQ;
 502        if (target->nfcid2_len)
 503                memcpy(atr_req->nfcid3, target->nfcid2, NFC_NFCID2_MAXSIZE);
 504        else
 505                get_random_bytes(atr_req->nfcid3, NFC_NFCID3_MAXSIZE);
 506
 507        atr_req->did = 0;
 508        atr_req->bs = 0;
 509        atr_req->br = 0;
 510
 511        ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
 512        payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
 513        atr_req->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
 514
 515        if (gb_len) {
 516                atr_req->pp |= DIGITAL_GB_BIT;
 517                skb_put_data(skb, gb, gb_len);
 518        }
 519
 520        digital_skb_push_dep_sod(ddev, skb);
 521
 522        ddev->skb_add_crc(skb);
 523
 524        rc = digital_in_send_cmd(ddev, skb, DIGITAL_ATR_RES_RWT,
 525                                 digital_in_recv_atr_res, target);
 526        if (rc)
 527                kfree_skb(skb);
 528
 529        return rc;
 530}
 531
 532static int digital_in_send_ack(struct nfc_digital_dev *ddev,
 533                               struct digital_data_exch *data_exch)
 534{
 535        struct digital_dep_req_res *dep_req;
 536        struct sk_buff *skb;
 537        int rc;
 538
 539        skb = digital_skb_alloc(ddev, 1);
 540        if (!skb)
 541                return -ENOMEM;
 542
 543        skb_push(skb, sizeof(struct digital_dep_req_res));
 544
 545        dep_req = (struct digital_dep_req_res *)skb->data;
 546
 547        dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 548        dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 549        dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 550                       ddev->curr_nfc_dep_pni;
 551
 552        digital_skb_push_dep_sod(ddev, skb);
 553
 554        ddev->skb_add_crc(skb);
 555
 556        ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
 557
 558        rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 559                                 digital_in_recv_dep_res, data_exch);
 560        if (rc) {
 561                kfree_skb(skb);
 562                kfree_skb(ddev->saved_skb);
 563                ddev->saved_skb = NULL;
 564        }
 565
 566        return rc;
 567}
 568
 569static int digital_in_send_nack(struct nfc_digital_dev *ddev,
 570                                struct digital_data_exch *data_exch)
 571{
 572        struct digital_dep_req_res *dep_req;
 573        struct sk_buff *skb;
 574        int rc;
 575
 576        skb = digital_skb_alloc(ddev, 1);
 577        if (!skb)
 578                return -ENOMEM;
 579
 580        skb_push(skb, sizeof(struct digital_dep_req_res));
 581
 582        dep_req = (struct digital_dep_req_res *)skb->data;
 583
 584        dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 585        dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 586        dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 587                       DIGITAL_NFC_DEP_PFB_NACK_BIT | ddev->curr_nfc_dep_pni;
 588
 589        digital_skb_push_dep_sod(ddev, skb);
 590
 591        ddev->skb_add_crc(skb);
 592
 593        rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 594                                 digital_in_recv_dep_res, data_exch);
 595        if (rc)
 596                kfree_skb(skb);
 597
 598        return rc;
 599}
 600
 601static int digital_in_send_atn(struct nfc_digital_dev *ddev,
 602                               struct digital_data_exch *data_exch)
 603{
 604        struct digital_dep_req_res *dep_req;
 605        struct sk_buff *skb;
 606        int rc;
 607
 608        skb = digital_skb_alloc(ddev, 1);
 609        if (!skb)
 610                return -ENOMEM;
 611
 612        skb_push(skb, sizeof(struct digital_dep_req_res));
 613
 614        dep_req = (struct digital_dep_req_res *)skb->data;
 615
 616        dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 617        dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 618        dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
 619
 620        digital_skb_push_dep_sod(ddev, skb);
 621
 622        ddev->skb_add_crc(skb);
 623
 624        rc = digital_in_send_cmd(ddev, skb, ddev->dep_rwt,
 625                                 digital_in_recv_dep_res, data_exch);
 626        if (rc)
 627                kfree_skb(skb);
 628
 629        return rc;
 630}
 631
 632static int digital_in_send_rtox(struct nfc_digital_dev *ddev,
 633                                struct digital_data_exch *data_exch, u8 rtox)
 634{
 635        struct digital_dep_req_res *dep_req;
 636        struct sk_buff *skb;
 637        int rc;
 638        u16 rwt_int;
 639
 640        rwt_int = ddev->dep_rwt * rtox;
 641        if (rwt_int > digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT])
 642                rwt_int = digital_rwt_map[DIGITAL_NFC_DEP_IN_MAX_WT];
 643
 644        skb = digital_skb_alloc(ddev, 1);
 645        if (!skb)
 646                return -ENOMEM;
 647
 648        skb_put_u8(skb, rtox);
 649
 650        skb_push(skb, sizeof(struct digital_dep_req_res));
 651
 652        dep_req = (struct digital_dep_req_res *)skb->data;
 653
 654        dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 655        dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 656        dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU |
 657                       DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT;
 658
 659        digital_skb_push_dep_sod(ddev, skb);
 660
 661        ddev->skb_add_crc(skb);
 662
 663        rc = digital_in_send_cmd(ddev, skb, rwt_int,
 664                                 digital_in_recv_dep_res, data_exch);
 665        if (rc)
 666                kfree_skb(skb);
 667
 668        return rc;
 669}
 670
 671static int digital_in_send_saved_skb(struct nfc_digital_dev *ddev,
 672                                     struct digital_data_exch *data_exch)
 673{
 674        int rc;
 675
 676        if (!ddev->saved_skb)
 677                return -EINVAL;
 678
 679        skb_get(ddev->saved_skb);
 680
 681        rc = digital_in_send_cmd(ddev, ddev->saved_skb, ddev->dep_rwt,
 682                                 digital_in_recv_dep_res, data_exch);
 683        if (rc)
 684                kfree_skb(ddev->saved_skb);
 685
 686        return rc;
 687}
 688
 689static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 690                                    struct sk_buff *resp)
 691{
 692        struct digital_data_exch *data_exch = arg;
 693        struct digital_dep_req_res *dep_res;
 694        u8 pfb;
 695        uint size;
 696        int rc;
 697        u8 rtox;
 698
 699        if (IS_ERR(resp)) {
 700                rc = PTR_ERR(resp);
 701                resp = NULL;
 702
 703                if ((rc == -EIO || (rc == -ETIMEDOUT && ddev->nack_count)) &&
 704                    (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 705                        ddev->atn_count = 0;
 706
 707                        rc = digital_in_send_nack(ddev, data_exch);
 708                        if (rc)
 709                                goto error;
 710
 711                        return;
 712                } else if ((rc == -ETIMEDOUT) &&
 713                           (ddev->atn_count++ < DIGITAL_NFC_DEP_N_RETRY_ATN)) {
 714                        ddev->nack_count = 0;
 715
 716                        rc = digital_in_send_atn(ddev, data_exch);
 717                        if (rc)
 718                                goto error;
 719
 720                        return;
 721                }
 722
 723                goto exit;
 724        }
 725
 726        rc = digital_skb_pull_dep_sod(ddev, resp);
 727        if (rc) {
 728                PROTOCOL_ERR("14.4.1.2");
 729                goto exit;
 730        }
 731
 732        rc = ddev->skb_check_crc(resp);
 733        if (rc) {
 734                if ((resp->len >= 4) &&
 735                    (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 736                        ddev->atn_count = 0;
 737
 738                        rc = digital_in_send_nack(ddev, data_exch);
 739                        if (rc)
 740                                goto error;
 741
 742                        kfree_skb(resp);
 743
 744                        return;
 745                }
 746
 747                PROTOCOL_ERR("14.4.1.6");
 748                goto error;
 749        }
 750
 751        ddev->atn_count = 0;
 752        ddev->nack_count = 0;
 753
 754        if (resp->len > ddev->local_payload_max) {
 755                rc = -EMSGSIZE;
 756                goto exit;
 757        }
 758
 759        size = sizeof(struct digital_dep_req_res);
 760        dep_res = (struct digital_dep_req_res *)resp->data;
 761
 762        if (resp->len < size || dep_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN ||
 763            dep_res->cmd != DIGITAL_CMD_DEP_RES) {
 764                rc = -EIO;
 765                goto error;
 766        }
 767
 768        pfb = dep_res->pfb;
 769
 770        if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
 771                PROTOCOL_ERR("14.8.2.1");
 772                rc = -EIO;
 773                goto error;
 774        }
 775
 776        if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
 777                rc = -EIO;
 778                goto exit;
 779        }
 780
 781        if (size > resp->len) {
 782                rc = -EIO;
 783                goto error;
 784        }
 785
 786        skb_pull(resp, size);
 787
 788        switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
 789        case DIGITAL_NFC_DEP_PFB_I_PDU:
 790                if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 791                        PROTOCOL_ERR("14.12.3.3");
 792                        rc = -EIO;
 793                        goto error;
 794                }
 795
 796                ddev->curr_nfc_dep_pni =
 797                        DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 798
 799                kfree_skb(ddev->saved_skb);
 800                ddev->saved_skb = NULL;
 801
 802                resp = digital_recv_dep_data_gather(ddev, pfb, resp,
 803                                                    digital_in_send_ack,
 804                                                    data_exch);
 805                if (IS_ERR(resp)) {
 806                        rc = PTR_ERR(resp);
 807                        resp = NULL;
 808                        goto error;
 809                }
 810
 811                /* If resp is NULL then we're still chaining so return and
 812                 * wait for the next part of the PDU.  Else, the PDU is
 813                 * complete so pass it up.
 814                 */
 815                if (!resp)
 816                        return;
 817
 818                rc = 0;
 819                break;
 820
 821        case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
 822                if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) {
 823                        PROTOCOL_ERR("14.12.4.5");
 824                        rc = -EIO;
 825                        goto exit;
 826                }
 827
 828                if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 829                        PROTOCOL_ERR("14.12.3.3");
 830                        rc = -EIO;
 831                        goto exit;
 832                }
 833
 834                ddev->curr_nfc_dep_pni =
 835                        DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 836
 837                if (!ddev->chaining_skb) {
 838                        PROTOCOL_ERR("14.12.4.3");
 839                        rc = -EIO;
 840                        goto exit;
 841                }
 842
 843                /* The initiator has received a valid ACK. Free the last sent
 844                 * PDU and keep on sending chained skb.
 845                 */
 846                kfree_skb(ddev->saved_skb);
 847                ddev->saved_skb = NULL;
 848
 849                rc = digital_in_send_dep_req(ddev, NULL,
 850                                             ddev->chaining_skb,
 851                                             ddev->data_exch);
 852                if (rc)
 853                        goto error;
 854
 855                goto free_resp;
 856
 857        case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
 858                if (!DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) { /* ATN */
 859                        rc = digital_in_send_saved_skb(ddev, data_exch);
 860                        if (rc)
 861                                goto error;
 862
 863                        goto free_resp;
 864                }
 865
 866                if (ddev->atn_count || ddev->nack_count) {
 867                        PROTOCOL_ERR("14.12.4.4");
 868                        rc = -EIO;
 869                        goto error;
 870                }
 871
 872                rtox = DIGITAL_NFC_DEP_RTOX_VALUE(resp->data[0]);
 873                if (!rtox || rtox > DIGITAL_NFC_DEP_RTOX_MAX) {
 874                        PROTOCOL_ERR("14.8.4.1");
 875                        rc = -EIO;
 876                        goto error;
 877                }
 878
 879                rc = digital_in_send_rtox(ddev, data_exch, rtox);
 880                if (rc)
 881                        goto error;
 882
 883                goto free_resp;
 884        }
 885
 886exit:
 887        data_exch->cb(data_exch->cb_context, resp, rc);
 888
 889error:
 890        kfree(data_exch);
 891
 892        kfree_skb(ddev->chaining_skb);
 893        ddev->chaining_skb = NULL;
 894
 895        kfree_skb(ddev->saved_skb);
 896        ddev->saved_skb = NULL;
 897
 898        if (rc)
 899                kfree_skb(resp);
 900
 901        return;
 902
 903free_resp:
 904        dev_kfree_skb(resp);
 905}
 906
 907int digital_in_send_dep_req(struct nfc_digital_dev *ddev,
 908                            struct nfc_target *target, struct sk_buff *skb,
 909                            struct digital_data_exch *data_exch)
 910{
 911        struct digital_dep_req_res *dep_req;
 912        struct sk_buff *chaining_skb, *tmp_skb;
 913        int rc;
 914
 915        skb_push(skb, sizeof(struct digital_dep_req_res));
 916
 917        dep_req = (struct digital_dep_req_res *)skb->data;
 918
 919        dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 920        dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 921        dep_req->pfb = ddev->curr_nfc_dep_pni;
 922
 923        ddev->atn_count = 0;
 924        ddev->nack_count = 0;
 925
 926        chaining_skb = ddev->chaining_skb;
 927
 928        tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_req, data_exch);
 929        if (IS_ERR(tmp_skb))
 930                return PTR_ERR(tmp_skb);
 931
 932        digital_skb_push_dep_sod(ddev, tmp_skb);
 933
 934        ddev->skb_add_crc(tmp_skb);
 935
 936        ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
 937
 938        rc = digital_in_send_cmd(ddev, tmp_skb, ddev->dep_rwt,
 939                                 digital_in_recv_dep_res, data_exch);
 940        if (rc) {
 941                if (tmp_skb != skb)
 942                        kfree_skb(tmp_skb);
 943
 944                kfree_skb(chaining_skb);
 945                ddev->chaining_skb = NULL;
 946
 947                kfree_skb(ddev->saved_skb);
 948                ddev->saved_skb = NULL;
 949        }
 950
 951        return rc;
 952}
 953
 954static void digital_tg_set_rf_tech(struct nfc_digital_dev *ddev, u8 rf_tech)
 955{
 956        ddev->curr_rf_tech = rf_tech;
 957
 958        ddev->skb_add_crc = digital_skb_add_crc_none;
 959        ddev->skb_check_crc = digital_skb_check_crc_none;
 960
 961        if (DIGITAL_DRV_CAPS_TG_CRC(ddev))
 962                return;
 963
 964        switch (ddev->curr_rf_tech) {
 965        case NFC_DIGITAL_RF_TECH_106A:
 966                ddev->skb_add_crc = digital_skb_add_crc_a;
 967                ddev->skb_check_crc = digital_skb_check_crc_a;
 968                break;
 969
 970        case NFC_DIGITAL_RF_TECH_212F:
 971        case NFC_DIGITAL_RF_TECH_424F:
 972                ddev->skb_add_crc = digital_skb_add_crc_f;
 973                ddev->skb_check_crc = digital_skb_check_crc_f;
 974                break;
 975
 976        default:
 977                break;
 978        }
 979}
 980
 981static int digital_tg_send_ack(struct nfc_digital_dev *ddev,
 982                               struct digital_data_exch *data_exch)
 983{
 984        struct digital_dep_req_res *dep_res;
 985        struct sk_buff *skb;
 986        int rc;
 987
 988        skb = digital_skb_alloc(ddev, 1);
 989        if (!skb)
 990                return -ENOMEM;
 991
 992        skb_push(skb, sizeof(struct digital_dep_req_res));
 993
 994        dep_res = (struct digital_dep_req_res *)skb->data;
 995
 996        dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
 997        dep_res->cmd = DIGITAL_CMD_DEP_RES;
 998        dep_res->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 999                       ddev->curr_nfc_dep_pni;
1000
1001        if (ddev->did) {
1002                dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1003
1004                skb_put_data(skb, &ddev->did, sizeof(ddev->did));
1005        }
1006
1007        ddev->curr_nfc_dep_pni =
1008                DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1009
1010        digital_skb_push_dep_sod(ddev, skb);
1011
1012        ddev->skb_add_crc(skb);
1013
1014        ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
1015
1016        rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
1017                                 data_exch);
1018        if (rc) {
1019                kfree_skb(skb);
1020                kfree_skb(ddev->saved_skb);
1021                ddev->saved_skb = NULL;
1022        }
1023
1024        return rc;
1025}
1026
1027static int digital_tg_send_atn(struct nfc_digital_dev *ddev)
1028{
1029        struct digital_dep_req_res *dep_res;
1030        struct sk_buff *skb;
1031        int rc;
1032
1033        skb = digital_skb_alloc(ddev, 1);
1034        if (!skb)
1035                return -ENOMEM;
1036
1037        skb_push(skb, sizeof(struct digital_dep_req_res));
1038
1039        dep_res = (struct digital_dep_req_res *)skb->data;
1040
1041        dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1042        dep_res->cmd = DIGITAL_CMD_DEP_RES;
1043        dep_res->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
1044
1045        if (ddev->did) {
1046                dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1047
1048                skb_put_data(skb, &ddev->did, sizeof(ddev->did));
1049        }
1050
1051        digital_skb_push_dep_sod(ddev, skb);
1052
1053        ddev->skb_add_crc(skb);
1054
1055        rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
1056                                 NULL);
1057        if (rc)
1058                kfree_skb(skb);
1059
1060        return rc;
1061}
1062
1063static int digital_tg_send_saved_skb(struct nfc_digital_dev *ddev)
1064{
1065        int rc;
1066
1067        if (!ddev->saved_skb)
1068                return -EINVAL;
1069
1070        skb_get(ddev->saved_skb);
1071
1072        rc = digital_tg_send_cmd(ddev, ddev->saved_skb, 1500,
1073                                 digital_tg_recv_dep_req, NULL);
1074        if (rc)
1075                kfree_skb(ddev->saved_skb);
1076
1077        return rc;
1078}
1079
1080static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
1081                                    struct sk_buff *resp)
1082{
1083        int rc;
1084        struct digital_dep_req_res *dep_req;
1085        u8 pfb;
1086        size_t size;
1087
1088        if (IS_ERR(resp)) {
1089                rc = PTR_ERR(resp);
1090                resp = NULL;
1091                goto exit;
1092        }
1093
1094        rc = ddev->skb_check_crc(resp);
1095        if (rc) {
1096                PROTOCOL_ERR("14.4.1.6");
1097                goto exit;
1098        }
1099
1100        rc = digital_skb_pull_dep_sod(ddev, resp);
1101        if (rc) {
1102                PROTOCOL_ERR("14.4.1.2");
1103                goto exit;
1104        }
1105
1106        if (resp->len > ddev->local_payload_max) {
1107                rc = -EMSGSIZE;
1108                goto exit;
1109        }
1110
1111        size = sizeof(struct digital_dep_req_res);
1112        dep_req = (struct digital_dep_req_res *)resp->data;
1113
1114        if (resp->len < size || dep_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1115            dep_req->cmd != DIGITAL_CMD_DEP_REQ) {
1116                rc = -EIO;
1117                goto exit;
1118        }
1119
1120        pfb = dep_req->pfb;
1121
1122        if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
1123                if (ddev->did && (ddev->did == resp->data[3])) {
1124                        size++;
1125                } else {
1126                        rc = -EIO;
1127                        goto exit;
1128                }
1129        } else if (ddev->did) {
1130                rc = -EIO;
1131                goto exit;
1132        }
1133
1134        if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
1135                rc = -EIO;
1136                goto exit;
1137        }
1138
1139        if (size > resp->len) {
1140                rc = -EIO;
1141                goto exit;
1142        }
1143
1144        skb_pull(resp, size);
1145
1146        switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
1147        case DIGITAL_NFC_DEP_PFB_I_PDU:
1148                pr_debug("DIGITAL_NFC_DEP_PFB_I_PDU\n");
1149
1150                if (ddev->atn_count) {
1151                        /* The target has received (and replied to) at least one
1152                         * ATN DEP_REQ.
1153                         */
1154                        ddev->atn_count = 0;
1155
1156                        /* pni of resp PDU equal to the target current pni - 1
1157                         * means resp is the previous DEP_REQ PDU received from
1158                         * the initiator so the target replies with saved_skb
1159                         * which is the previous DEP_RES saved in
1160                         * digital_tg_send_dep_res().
1161                         */
1162                        if (DIGITAL_NFC_DEP_PFB_PNI(pfb) ==
1163                          DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni - 1)) {
1164                                rc = digital_tg_send_saved_skb(ddev);
1165                                if (rc)
1166                                        goto exit;
1167
1168                                goto free_resp;
1169                        }
1170
1171                        /* atn_count > 0 and PDU pni != curr_nfc_dep_pni - 1
1172                         * means the target probably did not received the last
1173                         * DEP_REQ PDU sent by the initiator. The target
1174                         * fallbacks to normal processing then.
1175                         */
1176                }
1177
1178                if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
1179                        PROTOCOL_ERR("14.12.3.4");
1180                        rc = -EIO;
1181                        goto exit;
1182                }
1183
1184                kfree_skb(ddev->saved_skb);
1185                ddev->saved_skb = NULL;
1186
1187                resp = digital_recv_dep_data_gather(ddev, pfb, resp,
1188                                                    digital_tg_send_ack, NULL);
1189                if (IS_ERR(resp)) {
1190                        rc = PTR_ERR(resp);
1191                        resp = NULL;
1192                        goto exit;
1193                }
1194
1195                /* If resp is NULL then we're still chaining so return and
1196                 * wait for the next part of the PDU.  Else, the PDU is
1197                 * complete so pass it up.
1198                 */
1199                if (!resp)
1200                        return;
1201
1202                rc = 0;
1203                break;
1204        case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
1205                if (DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { /* NACK */
1206                        if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) !=
1207                                                ddev->curr_nfc_dep_pni) {
1208                                rc = -EIO;
1209                                goto exit;
1210                        }
1211
1212                        ddev->atn_count = 0;
1213
1214                        rc = digital_tg_send_saved_skb(ddev);
1215                        if (rc)
1216                                goto exit;
1217
1218                        goto free_resp;
1219                }
1220
1221                /* ACK */
1222                if (ddev->atn_count) {
1223                        /* The target has previously recevied one or more ATN
1224                         * PDUs.
1225                         */
1226                        ddev->atn_count = 0;
1227
1228                        /* If the ACK PNI is equal to the target PNI - 1 means
1229                         * that the initiator did not receive the previous PDU
1230                         * sent by the target so re-send it.
1231                         */
1232                        if (DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) ==
1233                                                ddev->curr_nfc_dep_pni) {
1234                                rc = digital_tg_send_saved_skb(ddev);
1235                                if (rc)
1236                                        goto exit;
1237
1238                                goto free_resp;
1239                        }
1240
1241                        /* Otherwise, the target did not receive the previous
1242                         * ACK PDU from the initiator. Fallback to normal
1243                         * processing of chained PDU then.
1244                         */
1245                }
1246
1247                /* Keep on sending chained PDU */
1248                if (!ddev->chaining_skb ||
1249                    DIGITAL_NFC_DEP_PFB_PNI(pfb) !=
1250                                        ddev->curr_nfc_dep_pni) {
1251                        rc = -EIO;
1252                        goto exit;
1253                }
1254
1255                kfree_skb(ddev->saved_skb);
1256                ddev->saved_skb = NULL;
1257
1258                rc = digital_tg_send_dep_res(ddev, ddev->chaining_skb);
1259                if (rc)
1260                        goto exit;
1261
1262                goto free_resp;
1263        case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
1264                if (DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) {
1265                        rc = -EINVAL;
1266                        goto exit;
1267                }
1268
1269                rc = digital_tg_send_atn(ddev);
1270                if (rc)
1271                        goto exit;
1272
1273                ddev->atn_count++;
1274
1275                goto free_resp;
1276        }
1277
1278        rc = nfc_tm_data_received(ddev->nfc_dev, resp);
1279
1280exit:
1281        kfree_skb(ddev->chaining_skb);
1282        ddev->chaining_skb = NULL;
1283
1284        ddev->atn_count = 0;
1285
1286        kfree_skb(ddev->saved_skb);
1287        ddev->saved_skb = NULL;
1288
1289        if (rc)
1290                kfree_skb(resp);
1291
1292        return;
1293
1294free_resp:
1295        dev_kfree_skb(resp);
1296}
1297
1298int digital_tg_send_dep_res(struct nfc_digital_dev *ddev, struct sk_buff *skb)
1299{
1300        struct digital_dep_req_res *dep_res;
1301        struct sk_buff *chaining_skb, *tmp_skb;
1302        int rc;
1303
1304        skb_push(skb, sizeof(struct digital_dep_req_res));
1305
1306        dep_res = (struct digital_dep_req_res *)skb->data;
1307
1308        dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1309        dep_res->cmd = DIGITAL_CMD_DEP_RES;
1310        dep_res->pfb = ddev->curr_nfc_dep_pni;
1311
1312        if (ddev->did) {
1313                dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1314
1315                skb_put_data(skb, &ddev->did, sizeof(ddev->did));
1316        }
1317
1318        ddev->curr_nfc_dep_pni =
1319                DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1320
1321        chaining_skb = ddev->chaining_skb;
1322
1323        tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_res, NULL);
1324        if (IS_ERR(tmp_skb))
1325                return PTR_ERR(tmp_skb);
1326
1327        digital_skb_push_dep_sod(ddev, tmp_skb);
1328
1329        ddev->skb_add_crc(tmp_skb);
1330
1331        ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
1332
1333        rc = digital_tg_send_cmd(ddev, tmp_skb, 1500, digital_tg_recv_dep_req,
1334                                 NULL);
1335        if (rc) {
1336                if (tmp_skb != skb)
1337                        kfree_skb(tmp_skb);
1338
1339                kfree_skb(chaining_skb);
1340                ddev->chaining_skb = NULL;
1341
1342                kfree_skb(ddev->saved_skb);
1343                ddev->saved_skb = NULL;
1344        }
1345
1346        return rc;
1347}
1348
1349static void digital_tg_send_psl_res_complete(struct nfc_digital_dev *ddev,
1350                                             void *arg, struct sk_buff *resp)
1351{
1352        u8 rf_tech = (unsigned long)arg;
1353
1354        if (IS_ERR(resp))
1355                return;
1356
1357        digital_tg_set_rf_tech(ddev, rf_tech);
1358
1359        digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
1360
1361        digital_tg_listen(ddev, 1500, digital_tg_recv_dep_req, NULL);
1362
1363        dev_kfree_skb(resp);
1364}
1365
1366static int digital_tg_send_psl_res(struct nfc_digital_dev *ddev, u8 did,
1367                                   u8 rf_tech)
1368{
1369        struct digital_psl_res *psl_res;
1370        struct sk_buff *skb;
1371        int rc;
1372
1373        skb = digital_skb_alloc(ddev, sizeof(struct digital_psl_res));
1374        if (!skb)
1375                return -ENOMEM;
1376
1377        skb_put(skb, sizeof(struct digital_psl_res));
1378
1379        psl_res = (struct digital_psl_res *)skb->data;
1380
1381        psl_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1382        psl_res->cmd = DIGITAL_CMD_PSL_RES;
1383        psl_res->did = did;
1384
1385        digital_skb_push_dep_sod(ddev, skb);
1386
1387        ddev->skb_add_crc(skb);
1388
1389        ddev->curr_nfc_dep_pni = 0;
1390
1391        rc = digital_tg_send_cmd(ddev, skb, 0, digital_tg_send_psl_res_complete,
1392                                 (void *)(unsigned long)rf_tech);
1393        if (rc)
1394                kfree_skb(skb);
1395
1396        return rc;
1397}
1398
1399static void digital_tg_recv_psl_req(struct nfc_digital_dev *ddev, void *arg,
1400                                    struct sk_buff *resp)
1401{
1402        int rc;
1403        struct digital_psl_req *psl_req;
1404        u8 rf_tech;
1405        u8 dsi, payload_size, payload_bits;
1406
1407        if (IS_ERR(resp)) {
1408                rc = PTR_ERR(resp);
1409                resp = NULL;
1410                goto exit;
1411        }
1412
1413        rc = ddev->skb_check_crc(resp);
1414        if (rc) {
1415                PROTOCOL_ERR("14.4.1.6");
1416                goto exit;
1417        }
1418
1419        rc = digital_skb_pull_dep_sod(ddev, resp);
1420        if (rc) {
1421                PROTOCOL_ERR("14.4.1.2");
1422                goto exit;
1423        }
1424
1425        psl_req = (struct digital_psl_req *)resp->data;
1426
1427        if (resp->len != sizeof(struct digital_psl_req) ||
1428            psl_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1429            psl_req->cmd != DIGITAL_CMD_PSL_REQ) {
1430                rc = -EIO;
1431                goto exit;
1432        }
1433
1434        dsi = (psl_req->brs >> 3) & 0x07;
1435        switch (dsi) {
1436        case 0:
1437                rf_tech = NFC_DIGITAL_RF_TECH_106A;
1438                break;
1439        case 1:
1440                rf_tech = NFC_DIGITAL_RF_TECH_212F;
1441                break;
1442        case 2:
1443                rf_tech = NFC_DIGITAL_RF_TECH_424F;
1444                break;
1445        default:
1446                pr_err("Unsupported dsi value %d\n", dsi);
1447                goto exit;
1448        }
1449
1450        payload_bits = DIGITAL_PAYLOAD_FSL_TO_BITS(psl_req->fsl);
1451        payload_size = digital_payload_bits_to_size(payload_bits);
1452
1453        if (!payload_size || (payload_size > min(ddev->local_payload_max,
1454                                                 ddev->remote_payload_max))) {
1455                rc = -EINVAL;
1456                goto exit;
1457        }
1458
1459        ddev->local_payload_max = payload_size;
1460        ddev->remote_payload_max = payload_size;
1461
1462        rc = digital_tg_send_psl_res(ddev, psl_req->did, rf_tech);
1463
1464exit:
1465        kfree_skb(resp);
1466}
1467
1468static void digital_tg_send_atr_res_complete(struct nfc_digital_dev *ddev,
1469                                             void *arg, struct sk_buff *resp)
1470{
1471        int offset;
1472
1473        if (IS_ERR(resp)) {
1474                digital_poll_next_tech(ddev);
1475                return;
1476        }
1477
1478        offset = 2;
1479        if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB)
1480                offset++;
1481
1482        ddev->atn_count = 0;
1483
1484        if (resp->data[offset] == DIGITAL_CMD_PSL_REQ)
1485                digital_tg_recv_psl_req(ddev, arg, resp);
1486        else
1487                digital_tg_recv_dep_req(ddev, arg, resp);
1488}
1489
1490static int digital_tg_send_atr_res(struct nfc_digital_dev *ddev,
1491                                   struct digital_atr_req *atr_req)
1492{
1493        struct digital_atr_res *atr_res;
1494        struct sk_buff *skb;
1495        u8 *gb, payload_bits;
1496        size_t gb_len;
1497        int rc;
1498
1499        gb = nfc_get_local_general_bytes(ddev->nfc_dev, &gb_len);
1500        if (!gb)
1501                gb_len = 0;
1502
1503        skb = digital_skb_alloc(ddev, sizeof(struct digital_atr_res) + gb_len);
1504        if (!skb)
1505                return -ENOMEM;
1506
1507        skb_put(skb, sizeof(struct digital_atr_res));
1508        atr_res = (struct digital_atr_res *)skb->data;
1509
1510        memset(atr_res, 0, sizeof(struct digital_atr_res));
1511
1512        atr_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1513        atr_res->cmd = DIGITAL_CMD_ATR_RES;
1514        memcpy(atr_res->nfcid3, atr_req->nfcid3, sizeof(atr_req->nfcid3));
1515        atr_res->to = DIGITAL_NFC_DEP_TG_MAX_WT;
1516
1517        ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
1518        payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
1519        atr_res->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
1520
1521        if (gb_len) {
1522                skb_put(skb, gb_len);
1523
1524                atr_res->pp |= DIGITAL_GB_BIT;
1525                memcpy(atr_res->gb, gb, gb_len);
1526        }
1527
1528        digital_skb_push_dep_sod(ddev, skb);
1529
1530        ddev->skb_add_crc(skb);
1531
1532        ddev->curr_nfc_dep_pni = 0;
1533
1534        rc = digital_tg_send_cmd(ddev, skb, 999,
1535                                 digital_tg_send_atr_res_complete, NULL);
1536        if (rc)
1537                kfree_skb(skb);
1538
1539        return rc;
1540}
1541
1542void digital_tg_recv_atr_req(struct nfc_digital_dev *ddev, void *arg,
1543                             struct sk_buff *resp)
1544{
1545        int rc;
1546        struct digital_atr_req *atr_req;
1547        size_t gb_len, min_size;
1548        u8 poll_tech_count, payload_bits;
1549
1550        if (IS_ERR(resp)) {
1551                rc = PTR_ERR(resp);
1552                resp = NULL;
1553                goto exit;
1554        }
1555
1556        if (!resp->len) {
1557                rc = -EIO;
1558                goto exit;
1559        }
1560
1561        if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB) {
1562                min_size = DIGITAL_ATR_REQ_MIN_SIZE + 2;
1563                digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_106A);
1564        } else {
1565                min_size = DIGITAL_ATR_REQ_MIN_SIZE + 1;
1566                digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_212F);
1567        }
1568
1569        if (resp->len < min_size) {
1570                rc = -EIO;
1571                goto exit;
1572        }
1573
1574        ddev->curr_protocol = NFC_PROTO_NFC_DEP_MASK;
1575
1576        rc = ddev->skb_check_crc(resp);
1577        if (rc) {
1578                PROTOCOL_ERR("14.4.1.6");
1579                goto exit;
1580        }
1581
1582        rc = digital_skb_pull_dep_sod(ddev, resp);
1583        if (rc) {
1584                PROTOCOL_ERR("14.4.1.2");
1585                goto exit;
1586        }
1587
1588        atr_req = (struct digital_atr_req *)resp->data;
1589
1590        if (atr_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1591            atr_req->cmd != DIGITAL_CMD_ATR_REQ ||
1592            atr_req->did > DIGITAL_DID_MAX) {
1593                rc = -EINVAL;
1594                goto exit;
1595        }
1596
1597        payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_req->pp);
1598        ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
1599
1600        if (!ddev->remote_payload_max) {
1601                rc = -EINVAL;
1602                goto exit;
1603        }
1604
1605        ddev->did = atr_req->did;
1606
1607        rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1608                                     NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED);
1609        if (rc)
1610                goto exit;
1611
1612        rc = digital_tg_send_atr_res(ddev, atr_req);
1613        if (rc)
1614                goto exit;
1615
1616        gb_len = resp->len - sizeof(struct digital_atr_req);
1617
1618        poll_tech_count = ddev->poll_tech_count;
1619        ddev->poll_tech_count = 0;
1620
1621        rc = nfc_tm_activated(ddev->nfc_dev, NFC_PROTO_NFC_DEP_MASK,
1622                              NFC_COMM_PASSIVE, atr_req->gb, gb_len);
1623        if (rc) {
1624                ddev->poll_tech_count = poll_tech_count;
1625                goto exit;
1626        }
1627
1628        rc = 0;
1629exit:
1630        if (rc)
1631                digital_poll_next_tech(ddev);
1632
1633        dev_kfree_skb(resp);
1634}
1635