net/nfc/digital_dep.c

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