drivers/nfc/st21nfca/st21nfca.c

   1 /*
   2  * HCI based Driver for STMicroelectronics NFC Chip
   3  *
   4  * Copyright (C) 2014  STMicroelectronics SAS. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/nfc.h>
  21 #include <net/nfc/hci.h>
  22 #include <net/nfc/llc.h>
  23
  24 #include "st21nfca.h"
  25
  26 #define DRIVER_DESC "HCI NFC driver for ST21NFCA"
  27
  28 #define FULL_VERSION_LEN 3
  29
  30 /* Proprietary gates, events, commands and registers */
  31
  32 /* Commands that apply to all RF readers */
  33 #define ST21NFCA_RF_READER_CMD_PRESENCE_CHECK   0x30
  34
  35 #define ST21NFCA_RF_READER_ISO15693_GATE        0x12
  36 #define ST21NFCA_RF_READER_ISO15693_INVENTORY 0x01
  37
  38 /*
  39  * Reader gate for communication with contact-less cards using Type A
  40  * protocol ISO14443-3 but not compliant with ISO14443-4
  41  */
  42 #define ST21NFCA_RF_READER_14443_3_A_GATE       0x15
  43 #define ST21NFCA_RF_READER_14443_3_A_UID        0x02
  44 #define ST21NFCA_RF_READER_14443_3_A_ATQA       0x03
  45 #define ST21NFCA_RF_READER_14443_3_A_SAK        0x04
  46
  47 #define ST21NFCA_DEVICE_MGNT_GATE               0x01
  48 #define ST21NFCA_DEVICE_MGNT_PIPE               0x02
  49
  50 #define ST21NFCA_DM_GETINFO         0x13
  51 #define ST21NFCA_DM_GETINFO_PIPE_LIST       0x02
  52 #define ST21NFCA_DM_GETINFO_PIPE_INFO       0x01
  53 #define ST21NFCA_DM_PIPE_CREATED        0x02
  54 #define ST21NFCA_DM_PIPE_OPEN           0x04
  55 #define ST21NFCA_DM_RF_ACTIVE           0x80
  56
  57 #define ST21NFCA_DM_IS_PIPE_OPEN(p) \
  58         ((p & 0x0f) == (ST21NFCA_DM_PIPE_CREATED | ST21NFCA_DM_PIPE_OPEN))
  59
  60 #define ST21NFCA_NFC_MODE       0x03    /* NFC_MODE parameter*/
  61
  62 static DECLARE_BITMAP(dev_mask, ST21NFCA_NUM_DEVICES);
  63
  64 static struct nfc_hci_gate st21nfca_gates[] = {
  65         {NFC_HCI_ADMIN_GATE, NFC_HCI_ADMIN_PIPE},
  66         {NFC_HCI_LOOPBACK_GATE, NFC_HCI_INVALID_PIPE},
  67         {NFC_HCI_ID_MGMT_GATE, NFC_HCI_INVALID_PIPE},
  68         {NFC_HCI_LINK_MGMT_GATE, NFC_HCI_LINK_MGMT_PIPE},
  69         {NFC_HCI_RF_READER_B_GATE, NFC_HCI_INVALID_PIPE},
  70         {NFC_HCI_RF_READER_A_GATE, NFC_HCI_INVALID_PIPE},
  71         {ST21NFCA_DEVICE_MGNT_GATE, ST21NFCA_DEVICE_MGNT_PIPE},
  72         {ST21NFCA_RF_READER_F_GATE, NFC_HCI_INVALID_PIPE},
  73         {ST21NFCA_RF_READER_14443_3_A_GATE, NFC_HCI_INVALID_PIPE},
  74         {ST21NFCA_RF_READER_ISO15693_GATE, NFC_HCI_INVALID_PIPE},
  75 };
  76
  77 struct st21nfca_pipe_info {
  78         u8 pipe_state;
  79         u8 src_host_id;
  80         u8 src_gate_id;
  81         u8 dst_host_id;
  82         u8 dst_gate_id;
  83 } __packed;
  84
  85 /* Largest headroom needed for outgoing custom commands */
  86 #define ST21NFCA_CMDS_HEADROOM  7
  87
  88 static int st21nfca_hci_load_session(struct nfc_hci_dev *hdev)
  89 {
  90         int i, j, r;
  91         struct sk_buff *skb_pipe_list, *skb_pipe_info;
  92         struct st21nfca_pipe_info *info;
  93
  94         u8 pipe_list[] = { ST21NFCA_DM_GETINFO_PIPE_LIST,
  95                 NFC_HCI_TERMINAL_HOST_ID
  96         };
  97         u8 pipe_info[] = { ST21NFCA_DM_GETINFO_PIPE_INFO,
  98                 NFC_HCI_TERMINAL_HOST_ID, 0
  99         };
 100
 101         skb_pipe_list = alloc_skb(ST21NFCA_HCI_LLC_MAX_SIZE, GFP_KERNEL);
 102         if (!skb_pipe_list) {
 103                 r = -ENOMEM;
 104                 goto free_list;
 105         }
 106
 107         skb_pipe_info = alloc_skb(ST21NFCA_HCI_LLC_MAX_SIZE, GFP_KERNEL);
 108         if (!skb_pipe_info) {
 109                 r = -ENOMEM;
 110                 goto free_info;
 111         }
 112
 113         /* On ST21NFCA device pipes number are dynamics
 114          * A maximum of 16 pipes can be created at the same time
 115          * If pipes are already created, hci_dev_up will fail.
 116          * Doing a clear all pipe is a bad idea because:
 117          * - It does useless EEPROM cycling
 118          * - It might cause issue for secure elements support
 119          * (such as removing connectivity or APDU reader pipe)
 120          * A better approach on ST21NFCA is to:
 121          * - get a pipe list for each host.
 122          * (eg: NFC_HCI_HOST_CONTROLLER_ID for now).
 123          * (TODO Later on UICC HOST and eSE HOST)
 124          * - get pipe information
 125          * - match retrieved pipe list in st21nfca_gates
 126          * ST21NFCA_DEVICE_MGNT_GATE is a proprietary gate
 127          * with ST21NFCA_DEVICE_MGNT_PIPE.
 128          * Pipe can be closed and need to be open.
 129          */
 130         r = nfc_hci_connect_gate(hdev, NFC_HCI_HOST_CONTROLLER_ID,
 131                 ST21NFCA_DEVICE_MGNT_GATE, ST21NFCA_DEVICE_MGNT_PIPE);
 132         if (r < 0)
 133                 goto free_info;
 134
 135         /* Get pipe list */
 136         r = nfc_hci_send_cmd(hdev, ST21NFCA_DEVICE_MGNT_GATE,
 137                         ST21NFCA_DM_GETINFO, pipe_list, sizeof(pipe_list),
 138                         &skb_pipe_list);
 139         if (r < 0)
 140                 goto free_info;
 141
 142         /* Complete the existing gate_pipe table */
 143         for (i = 0; i < skb_pipe_list->len; i++) {
 144                 pipe_info[2] = skb_pipe_list->data[i];
 145                 r = nfc_hci_send_cmd(hdev, ST21NFCA_DEVICE_MGNT_GATE,
 146                                         ST21NFCA_DM_GETINFO, pipe_info,
 147                                         sizeof(pipe_info), &skb_pipe_info);
 148
 149                 if (r)
 150                         continue;
 151
 152                 /*
 153                  * Match pipe ID and gate ID
 154                  * Output format from ST21NFC_DM_GETINFO is:
 155                  * - pipe state (1byte)
 156                  * - source hid (1byte)
 157                  * - source gid (1byte)
 158                  * - destination hid (1byte)
 159                  * - destination gid (1byte)
 160                  */
 161                 info = (struct st21nfca_pipe_info *) skb_pipe_info->data;
 162                 for (j = 0; (j < ARRAY_SIZE(st21nfca_gates)) &&
 163                         (st21nfca_gates[j].gate != info->dst_gate_id);
 164                         j++)
 165                         ;
 166
 167                 if (j < ARRAY_SIZE(st21nfca_gates) &&
 168                         st21nfca_gates[j].gate == info->dst_gate_id &&
 169                         ST21NFCA_DM_IS_PIPE_OPEN(info->pipe_state)) {
 170                         st21nfca_gates[j].pipe = pipe_info[2];
 171                         hdev->gate2pipe[st21nfca_gates[j].gate] =
 172                                 st21nfca_gates[j].pipe;
 173                 }
 174         }
 175
 176         /*
 177          * 3 gates have a well known pipe ID.
 178          * They will never appear in the pipe list
 179          */
 180         if (skb_pipe_list->len + 3 < ARRAY_SIZE(st21nfca_gates)) {
 181                 for (i = skb_pipe_list->len + 3;
 182                                 i < ARRAY_SIZE(st21nfca_gates); i++) {
 183                         r = nfc_hci_connect_gate(hdev,
 184                                         NFC_HCI_HOST_CONTROLLER_ID,
 185                                         st21nfca_gates[i].gate,
 186                                         st21nfca_gates[i].pipe);
 187                         if (r < 0)
 188                                 goto free_info;
 189                 }
 190         }
 191
 192         memcpy(hdev->init_data.gates, st21nfca_gates, sizeof(st21nfca_gates));
 193 free_info:
 194         kfree_skb(skb_pipe_info);
 195 free_list:
 196         kfree_skb(skb_pipe_list);
 197         return r;
 198 }
 199
 200 static int st21nfca_hci_open(struct nfc_hci_dev *hdev)
 201 {
 202         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 203         int r;
 204
 205         mutex_lock(&info->info_lock);
 206
 207         if (info->state != ST21NFCA_ST_COLD) {
 208                 r = -EBUSY;
 209                 goto out;
 210         }
 211
 212         r = info->phy_ops->enable(info->phy_id);
 213
 214         if (r == 0)
 215                 info->state = ST21NFCA_ST_READY;
 216
 217 out:
 218         mutex_unlock(&info->info_lock);
 219         return r;
 220 }
 221
 222 static void st21nfca_hci_close(struct nfc_hci_dev *hdev)
 223 {
 224         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 225
 226         mutex_lock(&info->info_lock);
 227
 228         if (info->state == ST21NFCA_ST_COLD)
 229                 goto out;
 230
 231         info->phy_ops->disable(info->phy_id);
 232         info->state = ST21NFCA_ST_COLD;
 233
 234 out:
 235         mutex_unlock(&info->info_lock);
 236 }
 237
 238 static int st21nfca_hci_ready(struct nfc_hci_dev *hdev)
 239 {
 240         struct sk_buff *skb;
 241
 242         u8 param;
 243         int r;
 244
 245         param = NFC_HCI_UICC_HOST_ID;
 246         r = nfc_hci_set_param(hdev, NFC_HCI_ADMIN_GATE,
 247                               NFC_HCI_ADMIN_WHITELIST, &param, 1);
 248         if (r < 0)
 249                 return r;
 250
 251         /* Set NFC_MODE in device management gate to enable */
 252         r = nfc_hci_get_param(hdev, ST21NFCA_DEVICE_MGNT_GATE,
 253                               ST21NFCA_NFC_MODE, &skb);
 254         if (r < 0)
 255                 return r;
 256
 257         if (skb->data[0] == 0) {
 258                 kfree_skb(skb);
 259                 param = 1;
 260
 261                 r = nfc_hci_set_param(hdev, ST21NFCA_DEVICE_MGNT_GATE,
 262                                         ST21NFCA_NFC_MODE, &param, 1);
 263                 if (r < 0)
 264                         return r;
 265         }
 266
 267         r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
 268                                NFC_HCI_EVT_END_OPERATION, NULL, 0);
 269         if (r < 0)
 270                 return r;
 271
 272         r = nfc_hci_get_param(hdev, NFC_HCI_ID_MGMT_GATE,
 273                               NFC_HCI_ID_MGMT_VERSION_SW, &skb);
 274         if (r < 0)
 275                 return r;
 276
 277         if (skb->len != FULL_VERSION_LEN) {
 278                 kfree_skb(skb);
 279                 return -EINVAL;
 280         }
 281
 282         print_hex_dump(KERN_DEBUG, "FULL VERSION SOFTWARE INFO: ",
 283                        DUMP_PREFIX_NONE, 16, 1,
 284                        skb->data, FULL_VERSION_LEN, false);
 285
 286         kfree_skb(skb);
 287
 288         return 0;
 289 }
 290
 291 static int st21nfca_hci_xmit(struct nfc_hci_dev *hdev, struct sk_buff *skb)
 292 {
 293         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 294
 295         return info->phy_ops->write(info->phy_id, skb);
 296 }
 297
 298 static int st21nfca_hci_start_poll(struct nfc_hci_dev *hdev,
 299                                    u32 im_protocols, u32 tm_protocols)
 300 {
 301         int r;
 302
 303         pr_info(DRIVER_DESC ": %s protocols 0x%x 0x%x\n",
 304                 __func__, im_protocols, tm_protocols);
 305
 306         r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
 307                                NFC_HCI_EVT_END_OPERATION, NULL, 0);
 308         if (r < 0)
 309                 return r;
 310         if (im_protocols) {
 311                 /*
 312                  * enable polling according to im_protocols & tm_protocols
 313                  * - CLOSE pipe according to im_protocols & tm_protocols
 314                  */
 315                 if ((NFC_HCI_RF_READER_B_GATE & im_protocols) == 0) {
 316                         r = nfc_hci_disconnect_gate(hdev,
 317                                         NFC_HCI_RF_READER_B_GATE);
 318                         if (r < 0)
 319                                 return r;
 320                 }
 321
 322                 if ((NFC_HCI_RF_READER_A_GATE & im_protocols) == 0) {
 323                         r = nfc_hci_disconnect_gate(hdev,
 324                                         NFC_HCI_RF_READER_A_GATE);
 325                         if (r < 0)
 326                                 return r;
 327                 }
 328
 329                 if ((ST21NFCA_RF_READER_F_GATE & im_protocols) == 0) {
 330                         r = nfc_hci_disconnect_gate(hdev,
 331                                         ST21NFCA_RF_READER_F_GATE);
 332                         if (r < 0)
 333                                 return r;
 334                 }
 335
 336                 if ((ST21NFCA_RF_READER_14443_3_A_GATE & im_protocols) == 0) {
 337                         r = nfc_hci_disconnect_gate(hdev,
 338                                         ST21NFCA_RF_READER_14443_3_A_GATE);
 339                         if (r < 0)
 340                                 return r;
 341                 }
 342
 343                 if ((ST21NFCA_RF_READER_ISO15693_GATE & im_protocols) == 0) {
 344                         r = nfc_hci_disconnect_gate(hdev,
 345                                         ST21NFCA_RF_READER_ISO15693_GATE);
 346                         if (r < 0)
 347                                 return r;
 348                 }
 349
 350                 r = nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
 351                                        NFC_HCI_EVT_READER_REQUESTED, NULL, 0);
 352                 if (r < 0)
 353                         nfc_hci_send_event(hdev, NFC_HCI_RF_READER_A_GATE,
 354                                            NFC_HCI_EVT_END_OPERATION, NULL, 0);
 355         }
 356         return r;
 357 }
 358
 359 static int st21nfca_get_iso14443_3_atqa(struct nfc_hci_dev *hdev, u16 *atqa)
 360 {
 361         int r;
 362         struct sk_buff *atqa_skb = NULL;
 363
 364         r = nfc_hci_get_param(hdev, ST21NFCA_RF_READER_14443_3_A_GATE,
 365                               ST21NFCA_RF_READER_14443_3_A_ATQA, &atqa_skb);
 366         if (r < 0)
 367                 goto exit;
 368
 369         if (atqa_skb->len != 2) {
 370                 r = -EPROTO;
 371                 goto exit;
 372         }
 373
 374         *atqa = be16_to_cpu(*(__be16 *) atqa_skb->data);
 375
 376 exit:
 377         kfree_skb(atqa_skb);
 378         return r;
 379 }
 380
 381 static int st21nfca_get_iso14443_3_sak(struct nfc_hci_dev *hdev, u8 *sak)
 382 {
 383         int r;
 384         struct sk_buff *sak_skb = NULL;
 385
 386         r = nfc_hci_get_param(hdev, ST21NFCA_RF_READER_14443_3_A_GATE,
 387                               ST21NFCA_RF_READER_14443_3_A_SAK, &sak_skb);
 388         if (r < 0)
 389                 goto exit;
 390
 391         if (sak_skb->len != 1) {
 392                 r = -EPROTO;
 393                 goto exit;
 394         }
 395
 396         *sak = sak_skb->data[0];
 397
 398 exit:
 399         kfree_skb(sak_skb);
 400         return r;
 401 }
 402
 403 static int st21nfca_get_iso14443_3_uid(struct nfc_hci_dev *hdev, u8 *gate,
 404                                        int *len)
 405 {
 406         int r;
 407         struct sk_buff *uid_skb = NULL;
 408
 409         r = nfc_hci_get_param(hdev, ST21NFCA_RF_READER_14443_3_A_GATE,
 410                               ST21NFCA_RF_READER_14443_3_A_UID, &uid_skb);
 411         if (r < 0)
 412                 goto exit;
 413
 414         if (uid_skb->len == 0 || uid_skb->len > NFC_NFCID1_MAXSIZE) {
 415                 r = -EPROTO;
 416                 goto exit;
 417         }
 418
 419         gate = uid_skb->data;
 420         *len = uid_skb->len;
 421 exit:
 422         kfree_skb(uid_skb);
 423         return r;
 424 }
 425
 426 static int st21nfca_get_iso15693_inventory(struct nfc_hci_dev *hdev,
 427                                            struct nfc_target *target)
 428 {
 429         int r;
 430         struct sk_buff *inventory_skb = NULL;
 431
 432         r = nfc_hci_get_param(hdev, ST21NFCA_RF_READER_ISO15693_GATE,
 433                               ST21NFCA_RF_READER_ISO15693_INVENTORY,
 434                               &inventory_skb);
 435         if (r < 0)
 436                 goto exit;
 437
 438         skb_pull(inventory_skb, 2);
 439
 440         if (inventory_skb->len == 0 ||
 441             inventory_skb->len > NFC_ISO15693_UID_MAXSIZE) {
 442                 r = -EPROTO;
 443                 goto exit;
 444         }
 445
 446         memcpy(target->iso15693_uid, inventory_skb->data, inventory_skb->len);
 447         target->iso15693_dsfid  = inventory_skb->data[1];
 448         target->is_iso15693 = 1;
 449 exit:
 450         kfree_skb(inventory_skb);
 451         return r;
 452 }
 453
 454 static int st21nfca_hci_target_from_gate(struct nfc_hci_dev *hdev, u8 gate,
 455                                          struct nfc_target *target)
 456 {
 457         int r, len;
 458         u16 atqa;
 459         u8 sak;
 460         u8 uid[NFC_NFCID1_MAXSIZE];
 461
 462         switch (gate) {
 463         case ST21NFCA_RF_READER_F_GATE:
 464                 target->supported_protocols = NFC_PROTO_FELICA_MASK;
 465                 break;
 466         case ST21NFCA_RF_READER_14443_3_A_GATE:
 467                 /* ISO14443-3 type 1 or 2 tags */
 468                 r = st21nfca_get_iso14443_3_atqa(hdev, &atqa);
 469                 if (r < 0)
 470                         return r;
 471                 if (atqa == 0x000c) {
 472                         target->supported_protocols = NFC_PROTO_JEWEL_MASK;
 473                         target->sens_res = 0x0c00;
 474                 } else {
 475                         r = st21nfca_get_iso14443_3_sak(hdev, &sak);
 476                         if (r < 0)
 477                                 return r;
 478
 479                         r = st21nfca_get_iso14443_3_uid(hdev, uid, &len);
 480                         if (r < 0)
 481                                 return r;
 482
 483                         target->supported_protocols =
 484                             nfc_hci_sak_to_protocol(sak);
 485                         if (target->supported_protocols == 0xffffffff)
 486                                 return -EPROTO;
 487
 488                         target->sens_res = atqa;
 489                         target->sel_res = sak;
 490                         memcpy(target->nfcid1, uid, len);
 491                         target->nfcid1_len = len;
 492                 }
 493
 494                 break;
 495         case ST21NFCA_RF_READER_ISO15693_GATE:
 496                 target->supported_protocols = NFC_PROTO_ISO15693_MASK;
 497                 r = st21nfca_get_iso15693_inventory(hdev, target);
 498                 if (r < 0)
 499                         return r;
 500                 break;
 501         default:
 502                 return -EPROTO;
 503         }
 504
 505         return 0;
 506 }
 507
 508 #define ST21NFCA_CB_TYPE_READER_ISO15693 1
 509 static void st21nfca_hci_data_exchange_cb(void *context, struct sk_buff *skb,
 510                                           int err)
 511 {
 512         struct st21nfca_hci_info *info = context;
 513
 514         switch (info->async_cb_type) {
 515         case ST21NFCA_CB_TYPE_READER_ISO15693:
 516                 if (err == 0)
 517                         skb_trim(skb, skb->len - 1);
 518                 info->async_cb(info->async_cb_context, skb, err);
 519                 break;
 520         default:
 521                 if (err == 0)
 522                         kfree_skb(skb);
 523                 break;
 524         }
 525 }
 526
 527 /*
 528  * Returns:
 529  * <= 0: driver handled the data exchange
 530  *    1: driver doesn't especially handle, please do standard processing
 531  */
 532 static int st21nfca_hci_im_transceive(struct nfc_hci_dev *hdev,
 533                                       struct nfc_target *target,
 534                                       struct sk_buff *skb,
 535                                       data_exchange_cb_t cb, void *cb_context)
 536 {
 537         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 538
 539         pr_info(DRIVER_DESC ": %s for gate=%d len=%d\n", __func__,
 540                 target->hci_reader_gate, skb->len);
 541
 542         switch (target->hci_reader_gate) {
 543         case ST21NFCA_RF_READER_F_GATE:
 544                 *skb_push(skb, 1) = 0x1a;
 545                 return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
 546                                               ST21NFCA_WR_XCHG_DATA, skb->data,
 547                                               skb->len, cb, cb_context);
 548         case ST21NFCA_RF_READER_14443_3_A_GATE:
 549                 *skb_push(skb, 1) = 0x1a;       /* CTR, see spec:10.2.2.1 */
 550
 551                 return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
 552                                               ST21NFCA_WR_XCHG_DATA, skb->data,
 553                                               skb->len, cb, cb_context);
 554         case ST21NFCA_RF_READER_ISO15693_GATE:
 555                 info->async_cb_type = ST21NFCA_CB_TYPE_READER_ISO15693;
 556                 info->async_cb = cb;
 557                 info->async_cb_context = cb_context;
 558
 559                 *skb_push(skb, 1) = 0x17;
 560
 561                 return nfc_hci_send_cmd_async(hdev, target->hci_reader_gate,
 562                                               ST21NFCA_WR_XCHG_DATA, skb->data,
 563                                               skb->len,
 564                                               st21nfca_hci_data_exchange_cb,
 565                                               info);
 566                 break;
 567         default:
 568                 return 1;
 569         }
 570 }
 571
 572 static int st21nfca_hci_check_presence(struct nfc_hci_dev *hdev,
 573                                        struct nfc_target *target)
 574 {
 575         u8 fwi = 0x11;
 576         switch (target->hci_reader_gate) {
 577         case NFC_HCI_RF_READER_A_GATE:
 578         case NFC_HCI_RF_READER_B_GATE:
 579                 /*
 580                  * PRESENCE_CHECK on those gates is available
 581                  * However, the answer to this command is taking 3 * fwi
 582                  * if the card is no present.
 583                  * Instead, we send an empty I-Frame with a very short
 584                  * configurable fwi ~604µs.
 585                  */
 586                 return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
 587                                         ST21NFCA_WR_XCHG_DATA, &fwi, 1, NULL);
 588         case ST21NFCA_RF_READER_14443_3_A_GATE:
 589                 return nfc_hci_send_cmd(hdev, target->hci_reader_gate,
 590                                         ST21NFCA_RF_READER_CMD_PRESENCE_CHECK,
 591                                         NULL, 0, NULL);
 592         default:
 593                 return -EOPNOTSUPP;
 594         }
 595 }
 596
 597 static struct nfc_hci_ops st21nfca_hci_ops = {
 598         .open = st21nfca_hci_open,
 599         .close = st21nfca_hci_close,
 600         .load_session = st21nfca_hci_load_session,
 601         .hci_ready = st21nfca_hci_ready,
 602         .xmit = st21nfca_hci_xmit,
 603         .start_poll = st21nfca_hci_start_poll,
 604         .target_from_gate = st21nfca_hci_target_from_gate,
 605         .im_transceive = st21nfca_hci_im_transceive,
 606         .check_presence = st21nfca_hci_check_presence,
 607 };
 608
 609 int st21nfca_hci_probe(void *phy_id, struct nfc_phy_ops *phy_ops,
 610                        char *llc_name, int phy_headroom, int phy_tailroom,
 611                        int phy_payload, struct nfc_hci_dev **hdev)
 612 {
 613         struct st21nfca_hci_info *info;
 614         int r = 0;
 615         int dev_num;
 616         u32 protocols;
 617         struct nfc_hci_init_data init_data;
 618         unsigned long quirks = 0;
 619
 620         info = kzalloc(sizeof(struct st21nfca_hci_info), GFP_KERNEL);
 621         if (!info) {
 622                 r = -ENOMEM;
 623                 goto err_alloc_hdev;
 624         }
 625
 626         info->phy_ops = phy_ops;
 627         info->phy_id = phy_id;
 628         info->state = ST21NFCA_ST_COLD;
 629         mutex_init(&info->info_lock);
 630
 631         init_data.gate_count = ARRAY_SIZE(st21nfca_gates);
 632
 633         memcpy(init_data.gates, st21nfca_gates, sizeof(st21nfca_gates));
 634
 635         /*
 636          * Session id must include the driver name + i2c bus addr
 637          * persistent info to discriminate 2 identical chips
 638          */
 639         dev_num = find_first_zero_bit(dev_mask, ST21NFCA_NUM_DEVICES);
 640         if (dev_num >= ST21NFCA_NUM_DEVICES)
 641                 goto err_alloc_hdev;
 642
 643         scnprintf(init_data.session_id, sizeof(init_data.session_id), "%s%2x",
 644                   "ST21AH", dev_num);
 645
 646         protocols = NFC_PROTO_JEWEL_MASK |
 647             NFC_PROTO_MIFARE_MASK |
 648             NFC_PROTO_FELICA_MASK |
 649             NFC_PROTO_ISO14443_MASK |
 650             NFC_PROTO_ISO14443_B_MASK |
 651             NFC_PROTO_ISO15693_MASK;
 652
 653         set_bit(NFC_HCI_QUIRK_SHORT_CLEAR, &quirks);
 654
 655         info->hdev =
 656             nfc_hci_allocate_device(&st21nfca_hci_ops, &init_data, quirks,
 657                                     protocols, llc_name,
 658                                     phy_headroom + ST21NFCA_CMDS_HEADROOM,
 659                                     phy_tailroom, phy_payload);
 660
 661         if (!info->hdev) {
 662                 pr_err("Cannot allocate nfc hdev.\n");
 663                 r = -ENOMEM;
 664                 goto err_alloc_hdev;
 665         }
 666
 667         nfc_hci_set_clientdata(info->hdev, info);
 668
 669         r = nfc_hci_register_device(info->hdev);
 670         if (r)
 671                 goto err_regdev;
 672
 673         *hdev = info->hdev;
 674
 675         return 0;
 676
 677 err_regdev:
 678         nfc_hci_free_device(info->hdev);
 679
 680 err_alloc_hdev:
 681         kfree(info);
 682
 683         return r;
 684 }
 685 EXPORT_SYMBOL(st21nfca_hci_probe);
 686
 687 void st21nfca_hci_remove(struct nfc_hci_dev *hdev)
 688 {
 689         struct st21nfca_hci_info *info = nfc_hci_get_clientdata(hdev);
 690
 691         nfc_hci_unregister_device(hdev);
 692         nfc_hci_free_device(hdev);
 693         kfree(info);
 694 }
 695 EXPORT_SYMBOL(st21nfca_hci_remove);
 696
 697 MODULE_LICENSE("GPL");
 698 MODULE_DESCRIPTION(DRIVER_DESC);