drivers/nfc/st21nfca/dep.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
   4  */
   5
   6 #include <net/nfc/hci.h>
   7
   8 #include "st21nfca.h"
   9
  10 #define ST21NFCA_NFCIP1_INITIATOR 0x00
  11 #define ST21NFCA_NFCIP1_REQ 0xd4
  12 #define ST21NFCA_NFCIP1_RES 0xd5
  13 #define ST21NFCA_NFCIP1_ATR_REQ 0x00
  14 #define ST21NFCA_NFCIP1_ATR_RES 0x01
  15 #define ST21NFCA_NFCIP1_PSL_REQ 0x04
  16 #define ST21NFCA_NFCIP1_PSL_RES 0x05
  17 #define ST21NFCA_NFCIP1_DEP_REQ 0x06
  18 #define ST21NFCA_NFCIP1_DEP_RES 0x07
  19
  20 #define ST21NFCA_NFC_DEP_PFB_PNI(pfb)     ((pfb) & 0x03)
  21 #define ST21NFCA_NFC_DEP_PFB_TYPE(pfb) ((pfb) & 0xE0)
  22 #define ST21NFCA_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
  23                                 ((pfb) & ST21NFCA_NFC_DEP_PFB_TIMEOUT_BIT)
  24 #define ST21NFCA_NFC_DEP_DID_BIT_SET(pfb) ((pfb) & 0x04)
  25 #define ST21NFCA_NFC_DEP_NAD_BIT_SET(pfb) ((pfb) & 0x08)
  26 #define ST21NFCA_NFC_DEP_PFB_TIMEOUT_BIT 0x10
  27
  28 #define ST21NFCA_NFC_DEP_PFB_IS_TIMEOUT(pfb) \
  29                                 ((pfb) & ST21NFCA_NFC_DEP_PFB_TIMEOUT_BIT)
  30
  31 #define ST21NFCA_NFC_DEP_PFB_I_PDU          0x00
  32 #define ST21NFCA_NFC_DEP_PFB_ACK_NACK_PDU   0x40
  33 #define ST21NFCA_NFC_DEP_PFB_SUPERVISOR_PDU 0x80
  34
  35 #define ST21NFCA_ATR_REQ_MIN_SIZE 17
  36 #define ST21NFCA_ATR_REQ_MAX_SIZE 65
  37 #define ST21NFCA_LR_BITS_PAYLOAD_SIZE_254B 0x30
  38 #define ST21NFCA_GB_BIT  0x02
  39
  40 #define ST21NFCA_EVT_SEND_DATA          0x10
  41 #define ST21NFCA_EVT_FIELD_ON           0x11
  42 #define ST21NFCA_EVT_CARD_DEACTIVATED   0x12
  43 #define ST21NFCA_EVT_CARD_ACTIVATED     0x13
  44 #define ST21NFCA_EVT_FIELD_OFF          0x14
  45
  46 #define ST21NFCA_EVT_CARD_F_BITRATE 0x16
  47 #define ST21NFCA_EVT_READER_F_BITRATE 0x13
  48 #define ST21NFCA_PSL_REQ_SEND_SPEED(brs) (brs & 0x38)
  49 #define ST21NFCA_PSL_REQ_RECV_SPEED(brs) (brs & 0x07)
  50 #define ST21NFCA_PP2LRI(pp) ((pp & 0x30) >> 4)
  51 #define ST21NFCA_CARD_BITRATE_212 0x01
  52 #define ST21NFCA_CARD_BITRATE_424 0x02
  53
  54 #define ST21NFCA_DEFAULT_TIMEOUT 0x0a
  55
  56
  57 #define PROTOCOL_ERR(req) pr_err("%d: ST21NFCA Protocol error: %s\n", \
  58                                  __LINE__, req)
  59
  60 struct st21nfca_atr_req {
  61         u8 length;
  62         u8 cmd0;
  63         u8 cmd1;
  64         u8 nfcid3[NFC_NFCID3_MAXSIZE];
  65         u8 did;
  66         u8 bsi;
  67         u8 bri;
  68         u8 ppi;
  69         u8 gbi[];
  70 } __packed;
  71
  72 struct st21nfca_atr_res {
  73         u8 length;
  74         u8 cmd0;
  75         u8 cmd1;
  76         u8 nfcid3[NFC_NFCID3_MAXSIZE];
  77         u8 did;
  78         u8 bsi;
  79         u8 bri;
  80         u8 to;
  81         u8 ppi;
  82         u8 gbi[];
  83 } __packed;
  84
  85 struct st21nfca_psl_req {
  86         u8 length;
  87         u8 cmd0;
  88         u8 cmd1;
  89         u8 did;
  90         u8 brs;
  91         u8 fsl;
  92 } __packed;
  93
  94 struct st21nfca_psl_res {
  95         u8 length;
  96         u8 cmd0;
  97         u8 cmd1;
  98         u8 did;
  99 } __packed;
 100
 101 struct st21nfca_dep_req_res {
 102         u8 length;
 103         u8 cmd0;
 104         u8 cmd1;
 105         u8 pfb;
 106         u8 did;
 107         u8 nad;
 108 } __packed;
 109
 110 static void st21nfca_tx_work(struct work_struct *work)
 111 {
 112         struct st21nfca_hci_info *info = container_of(work,
 113                                                 struct st21nfca_hci_info,
 114                                                 dep_info.tx_work);
 115
 116         struct nfc_dev *dev;
 117         struct sk_buff *skb;
 118
 119         if (info) {
 120                 dev = info->hdev->ndev;
 121                 skb = info->dep_info.tx_pending;
 122
 123                 device_lock(&dev->dev);
 124
 125                 nfc_hci_send_cmd_async(info->hdev, ST21NFCA_RF_READER_F_GATE,
 126                                 ST21NFCA_WR_XCHG_DATA, skb->data, skb->len,
 127                                 info->async_cb, info);
 128                 device_unlock(&dev->dev);
 129                 kfree_skb(skb);
 130         }
 131 }
 132
 133 static void st21nfca_im_send_pdu(struct st21nfca_hci_info *info,
 134                                                 struct sk_buff *skb)
 135 {
 136         info->dep_info.tx_pending = skb;
 137         schedule_work(&info->dep_info.tx_work);
 138 }
 139
 140 static int st21nfca_tm_send_atr_res(struct nfc_hci_dev *hdev,
 141                                     struct st21nfca_atr_req *atr_req)
 142 {
 143         struct st21nfca_atr_res *atr_res;
 144         struct sk_buff *skb;
 145         size_t gb_len;
 146         int r;
 147         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 148
 149         gb_len = atr_req->length - sizeof(struct st21nfca_atr_req);
 150         skb = alloc_skb(atr_req->length + 1, GFP_KERNEL);
 151         if (!skb)
 152                 return -ENOMEM;
 153
 154         skb_put(skb, sizeof(struct st21nfca_atr_res));
 155
 156         atr_res = (struct st21nfca_atr_res *)skb->data;
 157         memset(atr_res, 0, sizeof(struct st21nfca_atr_res));
 158
 159         atr_res->length = atr_req->length + 1;
 160         atr_res->cmd0 = ST21NFCA_NFCIP1_RES;
 161         atr_res->cmd1 = ST21NFCA_NFCIP1_ATR_RES;
 162
 163         memcpy(atr_res->nfcid3, atr_req->nfcid3, 6);
 164         atr_res->bsi = 0x00;
 165         atr_res->bri = 0x00;
 166         atr_res->to = ST21NFCA_DEFAULT_TIMEOUT;
 167         atr_res->ppi = ST21NFCA_LR_BITS_PAYLOAD_SIZE_254B;
 168
 169         if (gb_len) {
 170                 skb_put(skb, gb_len);
 171
 172                 atr_res->ppi |= ST21NFCA_GB_BIT;
 173                 memcpy(atr_res->gbi, atr_req->gbi, gb_len);
 174                 r = nfc_set_remote_general_bytes(hdev->ndev, atr_res->gbi,
 175                                                   gb_len);
 176                 if (r < 0) {
 177                         kfree_skb(skb);
 178                         return r;
 179                 }
 180         }
 181
 182         info->dep_info.curr_nfc_dep_pni = 0;
 183
 184         r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
 185                                 ST21NFCA_EVT_SEND_DATA, skb->data, skb->len);
 186         kfree_skb(skb);
 187         return r;
 188 }
 189
 190 static int st21nfca_tm_recv_atr_req(struct nfc_hci_dev *hdev,
 191                                     struct sk_buff *skb)
 192 {
 193         struct st21nfca_atr_req *atr_req;
 194         size_t gb_len;
 195         int r;
 196
 197         skb_trim(skb, skb->len - 1);
 198
 199         if (!skb->len)
 200                 return -EIO;
 201
 202         if (skb->len < ST21NFCA_ATR_REQ_MIN_SIZE)
 203                 return -EPROTO;
 204
 205         atr_req = (struct st21nfca_atr_req *)skb->data;
 206
 207         if (atr_req->length < sizeof(struct st21nfca_atr_req))
 208                 return -EPROTO;
 209
 210         r = st21nfca_tm_send_atr_res(hdev, atr_req);
 211         if (r)
 212                 return r;
 213
 214         gb_len = skb->len - sizeof(struct st21nfca_atr_req);
 215
 216         r = nfc_tm_activated(hdev->ndev, NFC_PROTO_NFC_DEP_MASK,
 217                               NFC_COMM_PASSIVE, atr_req->gbi, gb_len);
 218         if (r)
 219                 return r;
 220
 221         return 0;
 222 }
 223
 224 static int st21nfca_tm_send_psl_res(struct nfc_hci_dev *hdev,
 225                                     struct st21nfca_psl_req *psl_req)
 226 {
 227         struct st21nfca_psl_res *psl_res;
 228         struct sk_buff *skb;
 229         u8 bitrate[2] = {0, 0};
 230         int r;
 231
 232         skb = alloc_skb(sizeof(struct st21nfca_psl_res), GFP_KERNEL);
 233         if (!skb)
 234                 return -ENOMEM;
 235         skb_put(skb, sizeof(struct st21nfca_psl_res));
 236
 237         psl_res = (struct st21nfca_psl_res *)skb->data;
 238
 239         psl_res->length = sizeof(struct st21nfca_psl_res);
 240         psl_res->cmd0 = ST21NFCA_NFCIP1_RES;
 241         psl_res->cmd1 = ST21NFCA_NFCIP1_PSL_RES;
 242         psl_res->did = psl_req->did;
 243
 244         r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
 245                                 ST21NFCA_EVT_SEND_DATA, skb->data, skb->len);
 246         if (r < 0)
 247                 goto error;
 248
 249         /*
 250          * ST21NFCA only support P2P passive.
 251          * PSL_REQ BRS value != 0 has only a meaning to
 252          * change technology to type F.
 253          * We change to BITRATE 424Kbits.
 254          * In other case switch to BITRATE 106Kbits.
 255          */
 256         if (ST21NFCA_PSL_REQ_SEND_SPEED(psl_req->brs) &&
 257             ST21NFCA_PSL_REQ_RECV_SPEED(psl_req->brs)) {
 258                 bitrate[0] = ST21NFCA_CARD_BITRATE_424;
 259                 bitrate[1] = ST21NFCA_CARD_BITRATE_424;
 260         }
 261
 262         /* Send an event to change bitrate change event to card f */
 263         r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
 264                         ST21NFCA_EVT_CARD_F_BITRATE, bitrate, 2);
 265 error:
 266         kfree_skb(skb);
 267         return r;
 268 }
 269
 270 static int st21nfca_tm_recv_psl_req(struct nfc_hci_dev *hdev,
 271                                     struct sk_buff *skb)
 272 {
 273         struct st21nfca_psl_req *psl_req;
 274
 275         skb_trim(skb, skb->len - 1);
 276
 277         if (!skb->len)
 278                 return -EIO;
 279
 280         psl_req = (struct st21nfca_psl_req *)skb->data;
 281
 282         if (skb->len < sizeof(struct st21nfca_psl_req))
 283                 return -EIO;
 284
 285         return st21nfca_tm_send_psl_res(hdev, psl_req);
 286 }
 287
 288 int st21nfca_tm_send_dep_res(struct nfc_hci_dev *hdev, struct sk_buff *skb)
 289 {
 290         int r;
 291         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 292
 293         *(u8 *)skb_push(skb, 1) = info->dep_info.curr_nfc_dep_pni;
 294         *(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_DEP_RES;
 295         *(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_RES;
 296         *(u8 *)skb_push(skb, 1) = skb->len;
 297
 298         r = nfc_hci_send_event(hdev, ST21NFCA_RF_CARD_F_GATE,
 299                         ST21NFCA_EVT_SEND_DATA, skb->data, skb->len);
 300         kfree_skb(skb);
 301
 302         return r;
 303 }
 304 EXPORT_SYMBOL(st21nfca_tm_send_dep_res);
 305
 306 static int st21nfca_tm_recv_dep_req(struct nfc_hci_dev *hdev,
 307                                     struct sk_buff *skb)
 308 {
 309         struct st21nfca_dep_req_res *dep_req;
 310         u8 size;
 311         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 312
 313         skb_trim(skb, skb->len - 1);
 314
 315         size = 4;
 316
 317         dep_req = (struct st21nfca_dep_req_res *)skb->data;
 318         if (skb->len < size)
 319                 return -EIO;
 320
 321         if (ST21NFCA_NFC_DEP_DID_BIT_SET(dep_req->pfb))
 322                 size++;
 323         if (ST21NFCA_NFC_DEP_NAD_BIT_SET(dep_req->pfb))
 324                 size++;
 325
 326         if (skb->len < size)
 327                 return -EIO;
 328
 329         /* Receiving DEP_REQ - Decoding */
 330         switch (ST21NFCA_NFC_DEP_PFB_TYPE(dep_req->pfb)) {
 331         case ST21NFCA_NFC_DEP_PFB_I_PDU:
 332                 info->dep_info.curr_nfc_dep_pni =
 333                                 ST21NFCA_NFC_DEP_PFB_PNI(dep_req->pfb);
 334                 break;
 335         case ST21NFCA_NFC_DEP_PFB_ACK_NACK_PDU:
 336                 pr_err("Received a ACK/NACK PDU\n");
 337                 break;
 338         case ST21NFCA_NFC_DEP_PFB_SUPERVISOR_PDU:
 339                 pr_err("Received a SUPERVISOR PDU\n");
 340                 break;
 341         }
 342
 343         skb_pull(skb, size);
 344
 345         return nfc_tm_data_received(hdev->ndev, skb);
 346 }
 347
 348 static int st21nfca_tm_event_send_data(struct nfc_hci_dev *hdev,
 349                                 struct sk_buff *skb)
 350 {
 351         u8 cmd0, cmd1;
 352         int r;
 353
 354         cmd0 = skb->data[1];
 355         switch (cmd0) {
 356         case ST21NFCA_NFCIP1_REQ:
 357                 cmd1 = skb->data[2];
 358                 switch (cmd1) {
 359                 case ST21NFCA_NFCIP1_ATR_REQ:
 360                         r = st21nfca_tm_recv_atr_req(hdev, skb);
 361                         break;
 362                 case ST21NFCA_NFCIP1_PSL_REQ:
 363                         r = st21nfca_tm_recv_psl_req(hdev, skb);
 364                         break;
 365                 case ST21NFCA_NFCIP1_DEP_REQ:
 366                         r = st21nfca_tm_recv_dep_req(hdev, skb);
 367                         break;
 368                 default:
 369                         return 1;
 370                 }
 371                 break;
 372         default:
 373                 return 1;
 374         }
 375         return r;
 376 }
 377
 378 /*
 379  * Returns:
 380  * <= 0: driver handled the event, skb consumed
 381  *    1: driver does not handle the event, please do standard processing
 382  */
 383 int st21nfca_dep_event_received(struct nfc_hci_dev *hdev,
 384                                 u8 event, struct sk_buff *skb)
 385 {
 386         int r = 0;
 387         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 388
 389         pr_debug("dep event: %d\n", event);
 390
 391         switch (event) {
 392         case ST21NFCA_EVT_CARD_ACTIVATED:
 393                 info->dep_info.curr_nfc_dep_pni = 0;
 394                 break;
 395         case ST21NFCA_EVT_CARD_DEACTIVATED:
 396                 break;
 397         case ST21NFCA_EVT_FIELD_ON:
 398                 break;
 399         case ST21NFCA_EVT_FIELD_OFF:
 400                 break;
 401         case ST21NFCA_EVT_SEND_DATA:
 402                 r = st21nfca_tm_event_send_data(hdev, skb);
 403                 if (r < 0)
 404                         return r;
 405                 return 0;
 406         default:
 407                 nfc_err(&hdev->ndev->dev, "Unexpected event on card f gate\n");
 408                 return 1;
 409         }
 410         kfree_skb(skb);
 411         return r;
 412 }
 413 EXPORT_SYMBOL(st21nfca_dep_event_received);
 414
 415 static void st21nfca_im_send_psl_req(struct nfc_hci_dev *hdev, u8 did, u8 bsi,
 416                                      u8 bri, u8 lri)
 417 {
 418         struct sk_buff *skb;
 419         struct st21nfca_psl_req *psl_req;
 420         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 421
 422         skb =
 423             alloc_skb(sizeof(struct st21nfca_psl_req) + 1, GFP_KERNEL);
 424         if (!skb)
 425                 return;
 426         skb_reserve(skb, 1);
 427
 428         skb_put(skb, sizeof(struct st21nfca_psl_req));
 429         psl_req = (struct st21nfca_psl_req *) skb->data;
 430
 431         psl_req->length = sizeof(struct st21nfca_psl_req);
 432         psl_req->cmd0 = ST21NFCA_NFCIP1_REQ;
 433         psl_req->cmd1 = ST21NFCA_NFCIP1_PSL_REQ;
 434         psl_req->did = did;
 435         psl_req->brs = (0x30 & bsi << 4) | (bri & 0x03);
 436         psl_req->fsl = lri;
 437
 438         *(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10;
 439
 440         st21nfca_im_send_pdu(info, skb);
 441 }
 442
 443 #define ST21NFCA_CB_TYPE_READER_F 1
 444 static void st21nfca_im_recv_atr_res_cb(void *context, struct sk_buff *skb,
 445                                         int err)
 446 {
 447         struct st21nfca_hci_info *info = context;
 448         struct st21nfca_atr_res *atr_res;
 449         int r;
 450
 451         if (err != 0)
 452                 return;
 453
 454         if (!skb)
 455                 return;
 456
 457         switch (info->async_cb_type) {
 458         case ST21NFCA_CB_TYPE_READER_F:
 459                 skb_trim(skb, skb->len - 1);
 460                 atr_res = (struct st21nfca_atr_res *)skb->data;
 461                 r = nfc_set_remote_general_bytes(info->hdev->ndev,
 462                                 atr_res->gbi,
 463                                 skb->len - sizeof(struct st21nfca_atr_res));
 464                 if (r < 0)
 465                         return;
 466
 467                 if (atr_res->to >= 0x0e)
 468                         info->dep_info.to = 0x0e;
 469                 else
 470                         info->dep_info.to = atr_res->to + 1;
 471
 472                 info->dep_info.to |= 0x10;
 473
 474                 r = nfc_dep_link_is_up(info->hdev->ndev, info->dep_info.idx,
 475                                         NFC_COMM_PASSIVE, NFC_RF_INITIATOR);
 476                 if (r < 0)
 477                         return;
 478
 479                 info->dep_info.curr_nfc_dep_pni = 0;
 480                 if (ST21NFCA_PP2LRI(atr_res->ppi) != info->dep_info.lri)
 481                         st21nfca_im_send_psl_req(info->hdev, atr_res->did,
 482                                                 atr_res->bsi, atr_res->bri,
 483                                                 ST21NFCA_PP2LRI(atr_res->ppi));
 484                 break;
 485         default:
 486                 kfree_skb(skb);
 487                 break;
 488         }
 489 }
 490
 491 int st21nfca_im_send_atr_req(struct nfc_hci_dev *hdev, u8 *gb, size_t gb_len)
 492 {
 493         struct sk_buff *skb;
 494         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 495         struct st21nfca_atr_req *atr_req;
 496         struct nfc_target *target;
 497         uint size;
 498
 499         info->dep_info.to = ST21NFCA_DEFAULT_TIMEOUT;
 500         size = ST21NFCA_ATR_REQ_MIN_SIZE + gb_len;
 501         if (size > ST21NFCA_ATR_REQ_MAX_SIZE) {
 502                 PROTOCOL_ERR("14.6.1.1");
 503                 return -EINVAL;
 504         }
 505
 506         skb =
 507             alloc_skb(sizeof(struct st21nfca_atr_req) + gb_len + 1, GFP_KERNEL);
 508         if (!skb)
 509                 return -ENOMEM;
 510
 511         skb_reserve(skb, 1);
 512
 513         skb_put(skb, sizeof(struct st21nfca_atr_req));
 514
 515         atr_req = (struct st21nfca_atr_req *)skb->data;
 516         memset(atr_req, 0, sizeof(struct st21nfca_atr_req));
 517
 518         atr_req->cmd0 = ST21NFCA_NFCIP1_REQ;
 519         atr_req->cmd1 = ST21NFCA_NFCIP1_ATR_REQ;
 520         memset(atr_req->nfcid3, 0, NFC_NFCID3_MAXSIZE);
 521         target = hdev->ndev->targets;
 522
 523         if (target->sensf_res_len > 0)
 524                 memcpy(atr_req->nfcid3, target->sensf_res,
 525                                 target->sensf_res_len);
 526         else
 527                 get_random_bytes(atr_req->nfcid3, NFC_NFCID3_MAXSIZE);
 528
 529         atr_req->did = 0x0;
 530
 531         atr_req->bsi = 0x00;
 532         atr_req->bri = 0x00;
 533         atr_req->ppi = ST21NFCA_LR_BITS_PAYLOAD_SIZE_254B;
 534         if (gb_len) {
 535                 atr_req->ppi |= ST21NFCA_GB_BIT;
 536                 skb_put_data(skb, gb, gb_len);
 537         }
 538         atr_req->length = sizeof(struct st21nfca_atr_req) + hdev->gb_len;
 539
 540         *(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10; /* timeout */
 541
 542         info->async_cb_type = ST21NFCA_CB_TYPE_READER_F;
 543         info->async_cb_context = info;
 544         info->async_cb = st21nfca_im_recv_atr_res_cb;
 545         info->dep_info.bri = atr_req->bri;
 546         info->dep_info.bsi = atr_req->bsi;
 547         info->dep_info.lri = ST21NFCA_PP2LRI(atr_req->ppi);
 548
 549         return nfc_hci_send_cmd_async(hdev, ST21NFCA_RF_READER_F_GATE,
 550                                 ST21NFCA_WR_XCHG_DATA, skb->data,
 551                                 skb->len, info->async_cb, info);
 552 }
 553 EXPORT_SYMBOL(st21nfca_im_send_atr_req);
 554
 555 static void st21nfca_im_recv_dep_res_cb(void *context, struct sk_buff *skb,
 556                                         int err)
 557 {
 558         struct st21nfca_hci_info *info = context;
 559         struct st21nfca_dep_req_res *dep_res;
 560
 561         int size;
 562
 563         if (err != 0)
 564                 return;
 565
 566         if (!skb)
 567                 return;
 568
 569         switch (info->async_cb_type) {
 570         case ST21NFCA_CB_TYPE_READER_F:
 571                 dep_res = (struct st21nfca_dep_req_res *)skb->data;
 572
 573                 size = 3;
 574                 if (skb->len < size)
 575                         goto exit;
 576
 577                 if (ST21NFCA_NFC_DEP_DID_BIT_SET(dep_res->pfb))
 578                         size++;
 579                 if (ST21NFCA_NFC_DEP_NAD_BIT_SET(dep_res->pfb))
 580                         size++;
 581
 582                 if (skb->len < size)
 583                         goto exit;
 584
 585                 skb_trim(skb, skb->len - 1);
 586
 587                 /* Receiving DEP_REQ - Decoding */
 588                 switch (ST21NFCA_NFC_DEP_PFB_TYPE(dep_res->pfb)) {
 589                 case ST21NFCA_NFC_DEP_PFB_ACK_NACK_PDU:
 590                         pr_err("Received a ACK/NACK PDU\n");
 591                         fallthrough;
 592                 case ST21NFCA_NFC_DEP_PFB_I_PDU:
 593                         info->dep_info.curr_nfc_dep_pni =
 594                             ST21NFCA_NFC_DEP_PFB_PNI(dep_res->pfb + 1);
 595                         size++;
 596                         skb_pull(skb, size);
 597                         nfc_tm_data_received(info->hdev->ndev, skb);
 598                         break;
 599                 case ST21NFCA_NFC_DEP_PFB_SUPERVISOR_PDU:
 600                         pr_err("Received a SUPERVISOR PDU\n");
 601                         skb_pull(skb, size);
 602                         *(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_DEP_REQ;
 603                         *(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_REQ;
 604                         *(u8 *)skb_push(skb, 1) = skb->len;
 605                         *(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10;
 606
 607                         st21nfca_im_send_pdu(info, skb);
 608                         break;
 609                 }
 610
 611                 return;
 612         default:
 613                 break;
 614         }
 615
 616 exit:
 617         kfree_skb(skb);
 618 }
 619
 620 int st21nfca_im_send_dep_req(struct nfc_hci_dev *hdev, struct sk_buff *skb)
 621 {
 622         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 623
 624         info->async_cb_type = ST21NFCA_CB_TYPE_READER_F;
 625         info->async_cb_context = info;
 626         info->async_cb = st21nfca_im_recv_dep_res_cb;
 627
 628         *(u8 *)skb_push(skb, 1) = info->dep_info.curr_nfc_dep_pni;
 629         *(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_DEP_REQ;
 630         *(u8 *)skb_push(skb, 1) = ST21NFCA_NFCIP1_REQ;
 631         *(u8 *)skb_push(skb, 1) = skb->len;
 632
 633         *(u8 *)skb_push(skb, 1) = info->dep_info.to | 0x10;
 634
 635         return nfc_hci_send_cmd_async(hdev, ST21NFCA_RF_READER_F_GATE,
 636                                       ST21NFCA_WR_XCHG_DATA,
 637                                       skb->data, skb->len,
 638                                       info->async_cb, info);
 639 }
 640 EXPORT_SYMBOL(st21nfca_im_send_dep_req);
 641
 642 void st21nfca_dep_init(struct nfc_hci_dev *hdev)
 643 {
 644         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 645
 646         INIT_WORK(&info->dep_info.tx_work, st21nfca_tx_work);
 647         info->dep_info.curr_nfc_dep_pni = 0;
 648         info->dep_info.idx = 0;
 649         info->dep_info.to = ST21NFCA_DEFAULT_TIMEOUT;
 650 }
 651 EXPORT_SYMBOL(st21nfca_dep_init);
 652
 653 void st21nfca_dep_deinit(struct nfc_hci_dev *hdev)
 654 {
 655         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 656
 657         cancel_work_sync(&info->dep_info.tx_work);
 658 }
 659 EXPORT_SYMBOL(st21nfca_dep_deinit);