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 = pskb_copy(skb, GFP_KERNEL);
 528
 529         rc = digital_in_send_cmd(ddev, skb, 1500, digital_in_recv_dep_res,
 530                                  data_exch);
 531         if (rc) {
 532                 kfree_skb(skb);
 533                 kfree_skb(ddev->saved_skb);
 534                 ddev->saved_skb = NULL;
 535         }
 536
 537         return rc;
 538 }
 539
 540 static int digital_in_send_nack(struct nfc_digital_dev *ddev,
 541                                 struct digital_data_exch *data_exch)
 542 {
 543         struct digital_dep_req_res *dep_req;
 544         struct sk_buff *skb;
 545         int rc;
 546
 547         skb = digital_skb_alloc(ddev, 1);
 548         if (!skb)
 549                 return -ENOMEM;
 550
 551         skb_push(skb, sizeof(struct digital_dep_req_res));
 552
 553         dep_req = (struct digital_dep_req_res *)skb->data;
 554
 555         dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 556         dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 557         dep_req->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 558                        DIGITAL_NFC_DEP_PFB_NACK_BIT | ddev->curr_nfc_dep_pni;
 559
 560         digital_skb_push_dep_sod(ddev, skb);
 561
 562         ddev->skb_add_crc(skb);
 563
 564         rc = digital_in_send_cmd(ddev, skb, 1500, digital_in_recv_dep_res,
 565                                  data_exch);
 566         if (rc)
 567                 kfree_skb(skb);
 568
 569         return rc;
 570 }
 571
 572 static int digital_in_send_atn(struct nfc_digital_dev *ddev,
 573                                struct digital_data_exch *data_exch)
 574 {
 575         struct digital_dep_req_res *dep_req;
 576         struct sk_buff *skb;
 577         int rc;
 578
 579         skb = digital_skb_alloc(ddev, 1);
 580         if (!skb)
 581                 return -ENOMEM;
 582
 583         skb_push(skb, sizeof(struct digital_dep_req_res));
 584
 585         dep_req = (struct digital_dep_req_res *)skb->data;
 586
 587         dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 588         dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 589         dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
 590
 591         digital_skb_push_dep_sod(ddev, skb);
 592
 593         ddev->skb_add_crc(skb);
 594
 595         rc = digital_in_send_cmd(ddev, skb, 1500, digital_in_recv_dep_res,
 596                                  data_exch);
 597         if (rc)
 598                 kfree_skb(skb);
 599
 600         return rc;
 601 }
 602
 603 static int digital_in_send_rtox(struct nfc_digital_dev *ddev,
 604                                 struct digital_data_exch *data_exch, u8 rtox)
 605 {
 606         struct digital_dep_req_res *dep_req;
 607         struct sk_buff *skb;
 608         int rc;
 609
 610         skb = digital_skb_alloc(ddev, 1);
 611         if (!skb)
 612                 return -ENOMEM;
 613
 614         *skb_put(skb, 1) = rtox;
 615
 616         skb_push(skb, sizeof(struct digital_dep_req_res));
 617
 618         dep_req = (struct digital_dep_req_res *)skb->data;
 619
 620         dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 621         dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 622         dep_req->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU |
 623                        DIGITAL_NFC_DEP_PFB_TIMEOUT_BIT;
 624
 625         digital_skb_push_dep_sod(ddev, skb);
 626
 627         ddev->skb_add_crc(skb);
 628
 629         rc = digital_in_send_cmd(ddev, skb, 1500, digital_in_recv_dep_res,
 630                                  data_exch);
 631         if (rc)
 632                 kfree_skb(skb);
 633
 634         return rc;
 635 }
 636
 637 static int digital_in_send_saved_skb(struct nfc_digital_dev *ddev,
 638                                      struct digital_data_exch *data_exch)
 639 {
 640         int rc;
 641
 642         if (!ddev->saved_skb)
 643                 return -EINVAL;
 644
 645         skb_get(ddev->saved_skb);
 646
 647         rc = digital_in_send_cmd(ddev, ddev->saved_skb, 1500,
 648                                  digital_in_recv_dep_res, data_exch);
 649         if (rc)
 650                 kfree_skb(ddev->saved_skb);
 651
 652         return rc;
 653 }
 654
 655 static void digital_in_recv_dep_res(struct nfc_digital_dev *ddev, void *arg,
 656                                     struct sk_buff *resp)
 657 {
 658         struct digital_data_exch *data_exch = arg;
 659         struct digital_dep_req_res *dep_res;
 660         u8 pfb;
 661         uint size;
 662         int rc;
 663
 664         if (IS_ERR(resp)) {
 665                 rc = PTR_ERR(resp);
 666                 resp = NULL;
 667
 668                 if ((rc == -EIO || (rc == -ETIMEDOUT && ddev->nack_count)) &&
 669                     (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 670                         ddev->atn_count = 0;
 671
 672                         rc = digital_in_send_nack(ddev, data_exch);
 673                         if (rc)
 674                                 goto error;
 675
 676                         return;
 677                 } else if ((rc == -ETIMEDOUT) &&
 678                            (ddev->atn_count++ < DIGITAL_NFC_DEP_N_RETRY_ATN)) {
 679                         ddev->nack_count = 0;
 680
 681                         rc = digital_in_send_atn(ddev, data_exch);
 682                         if (rc)
 683                                 goto error;
 684
 685                         return;
 686                 }
 687
 688                 goto exit;
 689         }
 690
 691         rc = digital_skb_pull_dep_sod(ddev, resp);
 692         if (rc) {
 693                 PROTOCOL_ERR("14.4.1.2");
 694                 goto exit;
 695         }
 696
 697         rc = ddev->skb_check_crc(resp);
 698         if (rc) {
 699                 if ((resp->len >= 4) &&
 700                     (ddev->nack_count++ < DIGITAL_NFC_DEP_N_RETRY_NACK)) {
 701                         ddev->atn_count = 0;
 702
 703                         rc = digital_in_send_nack(ddev, data_exch);
 704                         if (rc)
 705                                 goto error;
 706
 707                         kfree_skb(resp);
 708
 709                         return;
 710                 }
 711
 712                 PROTOCOL_ERR("14.4.1.6");
 713                 goto error;
 714         }
 715
 716         ddev->atn_count = 0;
 717         ddev->nack_count = 0;
 718
 719         if (resp->len > ddev->local_payload_max) {
 720                 rc = -EMSGSIZE;
 721                 goto exit;
 722         }
 723
 724         size = sizeof(struct digital_dep_req_res);
 725         dep_res = (struct digital_dep_req_res *)resp->data;
 726
 727         if (resp->len < size || dep_res->dir != DIGITAL_NFC_DEP_FRAME_DIR_IN ||
 728             dep_res->cmd != DIGITAL_CMD_DEP_RES) {
 729                 rc = -EIO;
 730                 goto error;
 731         }
 732
 733         pfb = dep_res->pfb;
 734
 735         if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
 736                 PROTOCOL_ERR("14.8.2.1");
 737                 rc = -EIO;
 738                 goto error;
 739         }
 740
 741         if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
 742                 rc = -EIO;
 743                 goto exit;
 744         }
 745
 746         if (size > resp->len) {
 747                 rc = -EIO;
 748                 goto error;
 749         }
 750
 751         skb_pull(resp, size);
 752
 753         switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
 754         case DIGITAL_NFC_DEP_PFB_I_PDU:
 755                 if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 756                         PROTOCOL_ERR("14.12.3.3");
 757                         rc = -EIO;
 758                         goto error;
 759                 }
 760
 761                 ddev->curr_nfc_dep_pni =
 762                         DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 763
 764                 kfree_skb(ddev->saved_skb);
 765                 ddev->saved_skb = NULL;
 766
 767                 resp = digital_recv_dep_data_gather(ddev, pfb, resp,
 768                                                     digital_in_send_ack,
 769                                                     data_exch);
 770                 if (IS_ERR(resp)) {
 771                         rc = PTR_ERR(resp);
 772                         resp = NULL;
 773                         goto error;
 774                 }
 775
 776                 /* If resp is NULL then we're still chaining so return and
 777                  * wait for the next part of the PDU.  Else, the PDU is
 778                  * complete so pass it up.
 779                  */
 780                 if (!resp)
 781                         return;
 782
 783                 rc = 0;
 784                 break;
 785
 786         case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
 787                 if (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni) {
 788                         PROTOCOL_ERR("14.12.3.3");
 789                         rc = -EIO;
 790                         goto exit;
 791                 }
 792
 793                 ddev->curr_nfc_dep_pni =
 794                         DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 795
 796                 if (ddev->chaining_skb && !DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) {
 797                         kfree_skb(ddev->saved_skb);
 798                         ddev->saved_skb = NULL;
 799
 800                         rc = digital_in_send_dep_req(ddev, NULL,
 801                                                      ddev->chaining_skb,
 802                                                      ddev->data_exch);
 803                         if (rc)
 804                                 goto error;
 805
 806                         return;
 807                 }
 808
 809                 pr_err("Received a ACK/NACK PDU\n");
 810                 rc = -EINVAL;
 811                 goto exit;
 812
 813         case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
 814                 if (!DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) { /* ATN */
 815                         rc = digital_in_send_saved_skb(ddev, data_exch);
 816                         if (rc)
 817                                 goto error;
 818
 819                         return;
 820                 }
 821
 822                 rc = digital_in_send_rtox(ddev, data_exch, resp->data[0]);
 823                 if (rc)
 824                         goto error;
 825
 826                 kfree_skb(resp);
 827                 return;
 828         }
 829
 830 exit:
 831         data_exch->cb(data_exch->cb_context, resp, rc);
 832
 833 error:
 834         kfree(data_exch);
 835
 836         kfree_skb(ddev->chaining_skb);
 837         ddev->chaining_skb = NULL;
 838
 839         kfree_skb(ddev->saved_skb);
 840         ddev->saved_skb = NULL;
 841
 842         if (rc)
 843                 kfree_skb(resp);
 844 }
 845
 846 int digital_in_send_dep_req(struct nfc_digital_dev *ddev,
 847                             struct nfc_target *target, struct sk_buff *skb,
 848                             struct digital_data_exch *data_exch)
 849 {
 850         struct digital_dep_req_res *dep_req;
 851         struct sk_buff *chaining_skb, *tmp_skb;
 852         int rc;
 853
 854         skb_push(skb, sizeof(struct digital_dep_req_res));
 855
 856         dep_req = (struct digital_dep_req_res *)skb->data;
 857
 858         dep_req->dir = DIGITAL_NFC_DEP_FRAME_DIR_OUT;
 859         dep_req->cmd = DIGITAL_CMD_DEP_REQ;
 860         dep_req->pfb = ddev->curr_nfc_dep_pni;
 861
 862         ddev->atn_count = 0;
 863         ddev->nack_count = 0;
 864
 865         chaining_skb = ddev->chaining_skb;
 866
 867         tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_req, data_exch);
 868         if (IS_ERR(tmp_skb))
 869                 return PTR_ERR(tmp_skb);
 870
 871         digital_skb_push_dep_sod(ddev, tmp_skb);
 872
 873         ddev->skb_add_crc(tmp_skb);
 874
 875         ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
 876
 877         rc = digital_in_send_cmd(ddev, tmp_skb, 1500, digital_in_recv_dep_res,
 878                                  data_exch);
 879         if (rc) {
 880                 if (tmp_skb != skb)
 881                         kfree_skb(tmp_skb);
 882
 883                 kfree_skb(chaining_skb);
 884                 ddev->chaining_skb = NULL;
 885
 886                 kfree_skb(ddev->saved_skb);
 887                 ddev->saved_skb = NULL;
 888         }
 889
 890         return rc;
 891 }
 892
 893 static void digital_tg_set_rf_tech(struct nfc_digital_dev *ddev, u8 rf_tech)
 894 {
 895         ddev->curr_rf_tech = rf_tech;
 896
 897         ddev->skb_add_crc = digital_skb_add_crc_none;
 898         ddev->skb_check_crc = digital_skb_check_crc_none;
 899
 900         if (DIGITAL_DRV_CAPS_TG_CRC(ddev))
 901                 return;
 902
 903         switch (ddev->curr_rf_tech) {
 904         case NFC_DIGITAL_RF_TECH_106A:
 905                 ddev->skb_add_crc = digital_skb_add_crc_a;
 906                 ddev->skb_check_crc = digital_skb_check_crc_a;
 907                 break;
 908
 909         case NFC_DIGITAL_RF_TECH_212F:
 910         case NFC_DIGITAL_RF_TECH_424F:
 911                 ddev->skb_add_crc = digital_skb_add_crc_f;
 912                 ddev->skb_check_crc = digital_skb_check_crc_f;
 913                 break;
 914
 915         default:
 916                 break;
 917         }
 918 }
 919
 920 static int digital_tg_send_ack(struct nfc_digital_dev *ddev,
 921                                struct digital_data_exch *data_exch)
 922 {
 923         struct digital_dep_req_res *dep_res;
 924         struct sk_buff *skb;
 925         int rc;
 926
 927         skb = digital_skb_alloc(ddev, 1);
 928         if (!skb)
 929                 return -ENOMEM;
 930
 931         skb_push(skb, sizeof(struct digital_dep_req_res));
 932
 933         dep_res = (struct digital_dep_req_res *)skb->data;
 934
 935         dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
 936         dep_res->cmd = DIGITAL_CMD_DEP_RES;
 937         dep_res->pfb = DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU |
 938                        ddev->curr_nfc_dep_pni;
 939
 940         if (ddev->did) {
 941                 dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
 942
 943                 memcpy(skb_put(skb, sizeof(ddev->did)), &ddev->did,
 944                        sizeof(ddev->did));
 945         }
 946
 947         ddev->curr_nfc_dep_pni =
 948                 DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
 949
 950         digital_skb_push_dep_sod(ddev, skb);
 951
 952         ddev->skb_add_crc(skb);
 953
 954         ddev->saved_skb = pskb_copy(skb, GFP_KERNEL);
 955
 956         rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
 957                                  data_exch);
 958         if (rc) {
 959                 kfree_skb(skb);
 960                 kfree_skb(ddev->saved_skb);
 961                 ddev->saved_skb = NULL;
 962         }
 963
 964         return rc;
 965 }
 966
 967 static int digital_tg_send_atn(struct nfc_digital_dev *ddev)
 968 {
 969         struct digital_dep_req_res *dep_res;
 970         struct sk_buff *skb;
 971         int rc;
 972
 973         skb = digital_skb_alloc(ddev, 1);
 974         if (!skb)
 975                 return -ENOMEM;
 976
 977         skb_push(skb, sizeof(struct digital_dep_req_res));
 978
 979         dep_res = (struct digital_dep_req_res *)skb->data;
 980
 981         dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
 982         dep_res->cmd = DIGITAL_CMD_DEP_RES;
 983         dep_res->pfb = DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU;
 984
 985         if (ddev->did) {
 986                 dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
 987
 988                 memcpy(skb_put(skb, sizeof(ddev->did)), &ddev->did,
 989                        sizeof(ddev->did));
 990         }
 991
 992         digital_skb_push_dep_sod(ddev, skb);
 993
 994         ddev->skb_add_crc(skb);
 995
 996         rc = digital_tg_send_cmd(ddev, skb, 1500, digital_tg_recv_dep_req,
 997                                  NULL);
 998         if (rc)
 999                 kfree_skb(skb);
1000
1001         return rc;
1002 }
1003
1004 static int digital_tg_send_saved_skb(struct nfc_digital_dev *ddev)
1005 {
1006         int rc;
1007
1008         if (!ddev->saved_skb)
1009                 return -EINVAL;
1010
1011         skb_get(ddev->saved_skb);
1012
1013         rc = digital_tg_send_cmd(ddev, ddev->saved_skb, 1500,
1014                                  digital_tg_recv_dep_req, NULL);
1015         if (rc)
1016                 kfree_skb(ddev->saved_skb);
1017
1018         return rc;
1019 }
1020
1021 static void digital_tg_recv_dep_req(struct nfc_digital_dev *ddev, void *arg,
1022                                     struct sk_buff *resp)
1023 {
1024         int rc;
1025         struct digital_dep_req_res *dep_req;
1026         u8 pfb;
1027         size_t size;
1028
1029         if (IS_ERR(resp)) {
1030                 rc = PTR_ERR(resp);
1031                 resp = NULL;
1032                 goto exit;
1033         }
1034
1035         rc = ddev->skb_check_crc(resp);
1036         if (rc) {
1037                 PROTOCOL_ERR("14.4.1.6");
1038                 goto exit;
1039         }
1040
1041         rc = digital_skb_pull_dep_sod(ddev, resp);
1042         if (rc) {
1043                 PROTOCOL_ERR("14.4.1.2");
1044                 goto exit;
1045         }
1046
1047         if (resp->len > ddev->local_payload_max) {
1048                 rc = -EMSGSIZE;
1049                 goto exit;
1050         }
1051
1052         size = sizeof(struct digital_dep_req_res);
1053         dep_req = (struct digital_dep_req_res *)resp->data;
1054
1055         if (resp->len < size || dep_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1056             dep_req->cmd != DIGITAL_CMD_DEP_REQ) {
1057                 rc = -EIO;
1058                 goto exit;
1059         }
1060
1061         pfb = dep_req->pfb;
1062
1063         if (DIGITAL_NFC_DEP_DID_BIT_SET(pfb)) {
1064                 if (ddev->did && (ddev->did == resp->data[3])) {
1065                         size++;
1066                 } else {
1067                         rc = -EIO;
1068                         goto exit;
1069                 }
1070         } else if (ddev->did) {
1071                 rc = -EIO;
1072                 goto exit;
1073         }
1074
1075         if (DIGITAL_NFC_DEP_NAD_BIT_SET(pfb)) {
1076                 rc = -EIO;
1077                 goto exit;
1078         }
1079
1080         if (size > resp->len) {
1081                 rc = -EIO;
1082                 goto exit;
1083         }
1084
1085         skb_pull(resp, size);
1086
1087         switch (DIGITAL_NFC_DEP_PFB_TYPE(pfb)) {
1088         case DIGITAL_NFC_DEP_PFB_I_PDU:
1089                 pr_debug("DIGITAL_NFC_DEP_PFB_I_PDU\n");
1090
1091                 if ((ddev->atn_count && (DIGITAL_NFC_DEP_PFB_PNI(pfb - 1) !=
1092                                                 ddev->curr_nfc_dep_pni)) ||
1093                     (DIGITAL_NFC_DEP_PFB_PNI(pfb) != ddev->curr_nfc_dep_pni)) {
1094                         PROTOCOL_ERR("14.12.3.4");
1095                         rc = -EIO;
1096                         goto exit;
1097                 }
1098
1099                 if (ddev->atn_count) {
1100                         ddev->atn_count = 0;
1101
1102                         rc = digital_tg_send_saved_skb(ddev);
1103                         if (rc)
1104                                 goto exit;
1105
1106                         return;
1107                 }
1108
1109                 kfree_skb(ddev->saved_skb);
1110                 ddev->saved_skb = NULL;
1111
1112                 resp = digital_recv_dep_data_gather(ddev, pfb, resp,
1113                                                     digital_tg_send_ack, NULL);
1114                 if (IS_ERR(resp)) {
1115                         rc = PTR_ERR(resp);
1116                         resp = NULL;
1117                         goto exit;
1118                 }
1119
1120                 /* If resp is NULL then we're still chaining so return and
1121                  * wait for the next part of the PDU.  Else, the PDU is
1122                  * complete so pass it up.
1123                  */
1124                 if (!resp)
1125                         return;
1126
1127                 rc = 0;
1128                 break;
1129         case DIGITAL_NFC_DEP_PFB_ACK_NACK_PDU:
1130                 if (!DIGITAL_NFC_DEP_NACK_BIT_SET(pfb)) { /* ACK */
1131                         if ((ddev->atn_count &&
1132                              (DIGITAL_NFC_DEP_PFB_PNI(pfb - 1) !=
1133                                                 ddev->curr_nfc_dep_pni)) ||
1134                             (DIGITAL_NFC_DEP_PFB_PNI(pfb) !=
1135                                                 ddev->curr_nfc_dep_pni) ||
1136                             !ddev->chaining_skb || !ddev->saved_skb) {
1137                                 rc = -EIO;
1138                                 goto exit;
1139                         }
1140
1141                         if (ddev->atn_count) {
1142                                 ddev->atn_count = 0;
1143
1144                                 rc = digital_tg_send_saved_skb(ddev);
1145                                 if (rc)
1146                                         goto exit;
1147
1148                                 return;
1149                         }
1150
1151                         kfree_skb(ddev->saved_skb);
1152                         ddev->saved_skb = NULL;
1153
1154                         rc = digital_tg_send_dep_res(ddev, ddev->chaining_skb);
1155                         if (rc)
1156                                 goto exit;
1157                 } else { /* NACK */
1158                         if ((DIGITAL_NFC_DEP_PFB_PNI(pfb + 1) !=
1159                                                 ddev->curr_nfc_dep_pni) ||
1160                             !ddev->saved_skb) {
1161                                 rc = -EIO;
1162                                 goto exit;
1163                         }
1164
1165                         ddev->atn_count = 0;
1166
1167                         rc = digital_tg_send_saved_skb(ddev);
1168                         if (rc)
1169                                 goto exit;
1170                 }
1171
1172                 return;
1173         case DIGITAL_NFC_DEP_PFB_SUPERVISOR_PDU:
1174                 if (DIGITAL_NFC_DEP_PFB_IS_TIMEOUT(pfb)) {
1175                         rc = -EINVAL;
1176                         goto exit;
1177                 }
1178
1179                 rc = digital_tg_send_atn(ddev);
1180                 if (rc)
1181                         goto exit;
1182
1183                 ddev->atn_count++;
1184
1185                 kfree_skb(resp);
1186                 return;
1187         }
1188
1189         rc = nfc_tm_data_received(ddev->nfc_dev, resp);
1190
1191 exit:
1192         kfree_skb(ddev->chaining_skb);
1193         ddev->chaining_skb = NULL;
1194
1195         ddev->atn_count = 0;
1196
1197         kfree_skb(ddev->saved_skb);
1198         ddev->saved_skb = NULL;
1199
1200         if (rc)
1201                 kfree_skb(resp);
1202 }
1203
1204 int digital_tg_send_dep_res(struct nfc_digital_dev *ddev, struct sk_buff *skb)
1205 {
1206         struct digital_dep_req_res *dep_res;
1207         struct sk_buff *chaining_skb, *tmp_skb;
1208         int rc;
1209
1210         skb_push(skb, sizeof(struct digital_dep_req_res));
1211
1212         dep_res = (struct digital_dep_req_res *)skb->data;
1213
1214         dep_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1215         dep_res->cmd = DIGITAL_CMD_DEP_RES;
1216         dep_res->pfb = ddev->curr_nfc_dep_pni;
1217
1218         if (ddev->did) {
1219                 dep_res->pfb |= DIGITAL_NFC_DEP_PFB_DID_BIT;
1220
1221                 memcpy(skb_put(skb, sizeof(ddev->did)), &ddev->did,
1222                        sizeof(ddev->did));
1223         }
1224
1225         ddev->curr_nfc_dep_pni =
1226                 DIGITAL_NFC_DEP_PFB_PNI(ddev->curr_nfc_dep_pni + 1);
1227
1228         chaining_skb = ddev->chaining_skb;
1229
1230         tmp_skb = digital_send_dep_data_prep(ddev, skb, dep_res, NULL);
1231         if (IS_ERR(tmp_skb))
1232                 return PTR_ERR(tmp_skb);
1233
1234         digital_skb_push_dep_sod(ddev, tmp_skb);
1235
1236         ddev->skb_add_crc(tmp_skb);
1237
1238         ddev->saved_skb = pskb_copy(tmp_skb, GFP_KERNEL);
1239
1240         rc = digital_tg_send_cmd(ddev, tmp_skb, 1500, digital_tg_recv_dep_req,
1241                                  NULL);
1242         if (rc) {
1243                 if (tmp_skb != skb)
1244                         kfree_skb(tmp_skb);
1245
1246                 kfree_skb(chaining_skb);
1247                 ddev->chaining_skb = NULL;
1248
1249                 kfree_skb(ddev->saved_skb);
1250                 ddev->saved_skb = NULL;
1251         }
1252
1253         return rc;
1254 }
1255
1256 static void digital_tg_send_psl_res_complete(struct nfc_digital_dev *ddev,
1257                                              void *arg, struct sk_buff *resp)
1258 {
1259         u8 rf_tech = (unsigned long)arg;
1260
1261         if (IS_ERR(resp))
1262                 return;
1263
1264         digital_tg_set_rf_tech(ddev, rf_tech);
1265
1266         digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_RF_TECH, rf_tech);
1267
1268         digital_tg_listen(ddev, 1500, digital_tg_recv_dep_req, NULL);
1269
1270         dev_kfree_skb(resp);
1271 }
1272
1273 static int digital_tg_send_psl_res(struct nfc_digital_dev *ddev, u8 did,
1274                                    u8 rf_tech)
1275 {
1276         struct digital_psl_res *psl_res;
1277         struct sk_buff *skb;
1278         int rc;
1279
1280         skb = digital_skb_alloc(ddev, sizeof(struct digital_psl_res));
1281         if (!skb)
1282                 return -ENOMEM;
1283
1284         skb_put(skb, sizeof(struct digital_psl_res));
1285
1286         psl_res = (struct digital_psl_res *)skb->data;
1287
1288         psl_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1289         psl_res->cmd = DIGITAL_CMD_PSL_RES;
1290         psl_res->did = did;
1291
1292         digital_skb_push_dep_sod(ddev, skb);
1293
1294         ddev->skb_add_crc(skb);
1295
1296         ddev->curr_nfc_dep_pni = 0;
1297
1298         rc = digital_tg_send_cmd(ddev, skb, 0, digital_tg_send_psl_res_complete,
1299                                  (void *)(unsigned long)rf_tech);
1300         if (rc)
1301                 kfree_skb(skb);
1302
1303         return rc;
1304 }
1305
1306 static void digital_tg_recv_psl_req(struct nfc_digital_dev *ddev, void *arg,
1307                                     struct sk_buff *resp)
1308 {
1309         int rc;
1310         struct digital_psl_req *psl_req;
1311         u8 rf_tech;
1312         u8 dsi, payload_size, payload_bits;
1313
1314         if (IS_ERR(resp)) {
1315                 rc = PTR_ERR(resp);
1316                 resp = NULL;
1317                 goto exit;
1318         }
1319
1320         rc = ddev->skb_check_crc(resp);
1321         if (rc) {
1322                 PROTOCOL_ERR("14.4.1.6");
1323                 goto exit;
1324         }
1325
1326         rc = digital_skb_pull_dep_sod(ddev, resp);
1327         if (rc) {
1328                 PROTOCOL_ERR("14.4.1.2");
1329                 goto exit;
1330         }
1331
1332         psl_req = (struct digital_psl_req *)resp->data;
1333
1334         if (resp->len != sizeof(struct digital_psl_req) ||
1335             psl_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1336             psl_req->cmd != DIGITAL_CMD_PSL_REQ) {
1337                 rc = -EIO;
1338                 goto exit;
1339         }
1340
1341         dsi = (psl_req->brs >> 3) & 0x07;
1342         switch (dsi) {
1343         case 0:
1344                 rf_tech = NFC_DIGITAL_RF_TECH_106A;
1345                 break;
1346         case 1:
1347                 rf_tech = NFC_DIGITAL_RF_TECH_212F;
1348                 break;
1349         case 2:
1350                 rf_tech = NFC_DIGITAL_RF_TECH_424F;
1351                 break;
1352         default:
1353                 pr_err("Unsupported dsi value %d\n", dsi);
1354                 goto exit;
1355         }
1356
1357         payload_bits = DIGITAL_PAYLOAD_FSL_TO_BITS(psl_req->fsl);
1358         payload_size = digital_payload_bits_to_size(payload_bits);
1359
1360         if (!payload_size || (payload_size > min(ddev->local_payload_max,
1361                                                  ddev->remote_payload_max))) {
1362                 rc = -EINVAL;
1363                 goto exit;
1364         }
1365
1366         ddev->local_payload_max = payload_size;
1367         ddev->remote_payload_max = payload_size;
1368
1369         rc = digital_tg_send_psl_res(ddev, psl_req->did, rf_tech);
1370
1371 exit:
1372         kfree_skb(resp);
1373 }
1374
1375 static void digital_tg_send_atr_res_complete(struct nfc_digital_dev *ddev,
1376                                              void *arg, struct sk_buff *resp)
1377 {
1378         int offset;
1379
1380         if (IS_ERR(resp)) {
1381                 digital_poll_next_tech(ddev);
1382                 return;
1383         }
1384
1385         offset = 2;
1386         if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB)
1387                 offset++;
1388
1389         ddev->atn_count = 0;
1390
1391         if (resp->data[offset] == DIGITAL_CMD_PSL_REQ)
1392                 digital_tg_recv_psl_req(ddev, arg, resp);
1393         else
1394                 digital_tg_recv_dep_req(ddev, arg, resp);
1395 }
1396
1397 static int digital_tg_send_atr_res(struct nfc_digital_dev *ddev,
1398                                    struct digital_atr_req *atr_req)
1399 {
1400         struct digital_atr_res *atr_res;
1401         struct sk_buff *skb;
1402         u8 *gb, payload_bits;
1403         size_t gb_len;
1404         int rc;
1405
1406         gb = nfc_get_local_general_bytes(ddev->nfc_dev, &gb_len);
1407         if (!gb)
1408                 gb_len = 0;
1409
1410         skb = digital_skb_alloc(ddev, sizeof(struct digital_atr_res) + gb_len);
1411         if (!skb)
1412                 return -ENOMEM;
1413
1414         skb_put(skb, sizeof(struct digital_atr_res));
1415         atr_res = (struct digital_atr_res *)skb->data;
1416
1417         memset(atr_res, 0, sizeof(struct digital_atr_res));
1418
1419         atr_res->dir = DIGITAL_NFC_DEP_FRAME_DIR_IN;
1420         atr_res->cmd = DIGITAL_CMD_ATR_RES;
1421         memcpy(atr_res->nfcid3, atr_req->nfcid3, sizeof(atr_req->nfcid3));
1422         atr_res->to = 8;
1423
1424         ddev->local_payload_max = DIGITAL_PAYLOAD_SIZE_MAX;
1425         payload_bits = digital_payload_size_to_bits(ddev->local_payload_max);
1426         atr_res->pp = DIGITAL_PAYLOAD_BITS_TO_PP(payload_bits);
1427
1428         if (gb_len) {
1429                 skb_put(skb, gb_len);
1430
1431                 atr_res->pp |= DIGITAL_GB_BIT;
1432                 memcpy(atr_res->gb, gb, gb_len);
1433         }
1434
1435         digital_skb_push_dep_sod(ddev, skb);
1436
1437         ddev->skb_add_crc(skb);
1438
1439         ddev->curr_nfc_dep_pni = 0;
1440
1441         rc = digital_tg_send_cmd(ddev, skb, 999,
1442                                  digital_tg_send_atr_res_complete, NULL);
1443         if (rc)
1444                 kfree_skb(skb);
1445
1446         return rc;
1447 }
1448
1449 void digital_tg_recv_atr_req(struct nfc_digital_dev *ddev, void *arg,
1450                              struct sk_buff *resp)
1451 {
1452         int rc;
1453         struct digital_atr_req *atr_req;
1454         size_t gb_len, min_size;
1455         u8 poll_tech_count, payload_bits;
1456
1457         if (IS_ERR(resp)) {
1458                 rc = PTR_ERR(resp);
1459                 resp = NULL;
1460                 goto exit;
1461         }
1462
1463         if (!resp->len) {
1464                 rc = -EIO;
1465                 goto exit;
1466         }
1467
1468         if (resp->data[0] == DIGITAL_NFC_DEP_NFCA_SOD_SB) {
1469                 min_size = DIGITAL_ATR_REQ_MIN_SIZE + 2;
1470                 digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_106A);
1471         } else {
1472                 min_size = DIGITAL_ATR_REQ_MIN_SIZE + 1;
1473                 digital_tg_set_rf_tech(ddev, NFC_DIGITAL_RF_TECH_212F);
1474         }
1475
1476         if (resp->len < min_size) {
1477                 rc = -EIO;
1478                 goto exit;
1479         }
1480
1481         ddev->curr_protocol = NFC_PROTO_NFC_DEP_MASK;
1482
1483         rc = ddev->skb_check_crc(resp);
1484         if (rc) {
1485                 PROTOCOL_ERR("14.4.1.6");
1486                 goto exit;
1487         }
1488
1489         rc = digital_skb_pull_dep_sod(ddev, resp);
1490         if (rc) {
1491                 PROTOCOL_ERR("14.4.1.2");
1492                 goto exit;
1493         }
1494
1495         atr_req = (struct digital_atr_req *)resp->data;
1496
1497         if (atr_req->dir != DIGITAL_NFC_DEP_FRAME_DIR_OUT ||
1498             atr_req->cmd != DIGITAL_CMD_ATR_REQ ||
1499             atr_req->did > DIGITAL_DID_MAX) {
1500                 rc = -EINVAL;
1501                 goto exit;
1502         }
1503
1504         payload_bits = DIGITAL_PAYLOAD_PP_TO_BITS(atr_req->pp);
1505         ddev->remote_payload_max = digital_payload_bits_to_size(payload_bits);
1506
1507         if (!ddev->remote_payload_max) {
1508                 rc = -EINVAL;
1509                 goto exit;
1510         }
1511
1512         ddev->did = atr_req->did;
1513
1514         rc = digital_tg_configure_hw(ddev, NFC_DIGITAL_CONFIG_FRAMING,
1515                                      NFC_DIGITAL_FRAMING_NFC_DEP_ACTIVATED);
1516         if (rc)
1517                 goto exit;
1518
1519         rc = digital_tg_send_atr_res(ddev, atr_req);
1520         if (rc)
1521                 goto exit;
1522
1523         gb_len = resp->len - sizeof(struct digital_atr_req);
1524
1525         poll_tech_count = ddev->poll_tech_count;
1526         ddev->poll_tech_count = 0;
1527
1528         rc = nfc_tm_activated(ddev->nfc_dev, NFC_PROTO_NFC_DEP_MASK,
1529                               NFC_COMM_PASSIVE, atr_req->gb, gb_len);
1530         if (rc) {
1531                 ddev->poll_tech_count = poll_tech_count;
1532                 goto exit;
1533         }
1534
1535         rc = 0;
1536 exit:
1537         if (rc)
1538                 digital_poll_next_tech(ddev);
1539
1540         dev_kfree_skb(resp);
1541 }