drivers/misc/mei/nfc.c

   1 /*
   2  *
   3  * Intel Management Engine Interface (Intel MEI) Linux driver
   4  * Copyright (c) 2003-2013, Intel Corporation.
   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 it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  */
  16
  17 #include <linux/kernel.h>
  18 #include <linux/sched.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/device.h>
  22 #include <linux/slab.h>
  23
  24 #include <linux/mei_cl_bus.h>
  25
  26 #include "mei_dev.h"
  27 #include "client.h"
  28
  29 struct mei_nfc_cmd {
  30         u8 command;
  31         u8 status;
  32         u16 req_id;
  33         u32 reserved;
  34         u16 data_size;
  35         u8 sub_command;
  36         u8 data[];
  37 } __packed;
  38
  39 struct mei_nfc_reply {
  40         u8 command;
  41         u8 status;
  42         u16 req_id;
  43         u32 reserved;
  44         u16 data_size;
  45         u8 sub_command;
  46         u8 reply_status;
  47         u8 data[];
  48 } __packed;
  49
  50 struct mei_nfc_if_version {
  51         u8 radio_version_sw[3];
  52         u8 reserved[3];
  53         u8 radio_version_hw[3];
  54         u8 i2c_addr;
  55         u8 fw_ivn;
  56         u8 vendor_id;
  57         u8 radio_type;
  58 } __packed;
  59
  60 struct mei_nfc_connect {
  61         u8 fw_ivn;
  62         u8 vendor_id;
  63 } __packed;
  64
  65 struct mei_nfc_connect_resp {
  66         u8 fw_ivn;
  67         u8 vendor_id;
  68         u16 me_major;
  69         u16 me_minor;
  70         u16 me_hotfix;
  71         u16 me_build;
  72 } __packed;
  73
  74 struct mei_nfc_hci_hdr {
  75         u8 cmd;
  76         u8 status;
  77         u16 req_id;
  78         u32 reserved;
  79         u16 data_size;
  80 } __packed;
  81
  82 #define MEI_NFC_CMD_MAINTENANCE 0x00
  83 #define MEI_NFC_CMD_HCI_SEND 0x01
  84 #define MEI_NFC_CMD_HCI_RECV 0x02
  85
  86 #define MEI_NFC_SUBCMD_CONNECT    0x00
  87 #define MEI_NFC_SUBCMD_IF_VERSION 0x01
  88
  89 #define MEI_NFC_HEADER_SIZE 10
  90
  91 /**
  92  * struct mei_nfc_dev - NFC mei device
  93  *
  94  * @cl: NFC host client
  95  * @cl_info: NFC info host client
  96  * @init_work: perform connection to the info client
  97  * @send_wq: send completion wait queue
  98  * @fw_ivn: NFC Interface Version Number
  99  * @vendor_id: NFC manufacturer ID
 100  * @radio_type: NFC radio type
 101  * @bus_name: bus name
 102  *
 103  * @req_id:  message counter
 104  * @recv_req_id: reception message counter
 105  */
 106 struct mei_nfc_dev {
 107         struct mei_cl *cl;
 108         struct mei_cl *cl_info;
 109         struct work_struct init_work;
 110         wait_queue_head_t send_wq;
 111         u8 fw_ivn;
 112         u8 vendor_id;
 113         u8 radio_type;
 114         char *bus_name;
 115
 116         u16 req_id;
 117         u16 recv_req_id;
 118 };
 119
 120 static struct mei_nfc_dev nfc_dev;
 121
 122 /* UUIDs for NFC F/W clients */
 123 const uuid_le mei_nfc_guid = UUID_LE(0x0bb17a78, 0x2a8e, 0x4c50,
 124                                      0x94, 0xd4, 0x50, 0x26,
 125                                      0x67, 0x23, 0x77, 0x5c);
 126
 127 static const uuid_le mei_nfc_info_guid = UUID_LE(0xd2de1625, 0x382d, 0x417d,
 128                                         0x48, 0xa4, 0xef, 0xab,
 129                                         0xba, 0x8a, 0x12, 0x06);
 130
 131 /* Vendors */
 132 #define MEI_NFC_VENDOR_INSIDE 0x00
 133 #define MEI_NFC_VENDOR_NXP    0x01
 134
 135 /* Radio types */
 136 #define MEI_NFC_VENDOR_INSIDE_UREAD 0x00
 137 #define MEI_NFC_VENDOR_NXP_PN544    0x01
 138
 139 static void mei_nfc_free(struct mei_nfc_dev *ndev)
 140 {
 141         if (ndev->cl) {
 142                 list_del(&ndev->cl->device_link);
 143                 mei_cl_unlink(ndev->cl);
 144                 kfree(ndev->cl);
 145         }
 146
 147         if (ndev->cl_info) {
 148                 list_del(&ndev->cl_info->device_link);
 149                 mei_cl_unlink(ndev->cl_info);
 150                 kfree(ndev->cl_info);
 151         }
 152
 153         memset(ndev, 0, sizeof(struct mei_nfc_dev));
 154 }
 155
 156 static int mei_nfc_build_bus_name(struct mei_nfc_dev *ndev)
 157 {
 158         struct mei_device *dev;
 159
 160         if (!ndev->cl)
 161                 return -ENODEV;
 162
 163         dev = ndev->cl->dev;
 164
 165         switch (ndev->vendor_id) {
 166         case MEI_NFC_VENDOR_INSIDE:
 167                 switch (ndev->radio_type) {
 168                 case MEI_NFC_VENDOR_INSIDE_UREAD:
 169                         ndev->bus_name = "microread";
 170                         return 0;
 171
 172                 default:
 173                         dev_err(dev->dev, "Unknown radio type 0x%x\n",
 174                                 ndev->radio_type);
 175
 176                         return -EINVAL;
 177                 }
 178
 179         case MEI_NFC_VENDOR_NXP:
 180                 switch (ndev->radio_type) {
 181                 case MEI_NFC_VENDOR_NXP_PN544:
 182                         ndev->bus_name = "pn544";
 183                         return 0;
 184                 default:
 185                         dev_err(dev->dev, "Unknown radio type 0x%x\n",
 186                                 ndev->radio_type);
 187
 188                         return -EINVAL;
 189                 }
 190
 191         default:
 192                 dev_err(dev->dev, "Unknown vendor ID 0x%x\n",
 193                         ndev->vendor_id);
 194
 195                 return -EINVAL;
 196         }
 197
 198         return 0;
 199 }
 200
 201 static int mei_nfc_connect(struct mei_nfc_dev *ndev)
 202 {
 203         struct mei_device *dev;
 204         struct mei_cl *cl;
 205         struct mei_nfc_cmd *cmd, *reply;
 206         struct mei_nfc_connect *connect;
 207         struct mei_nfc_connect_resp *connect_resp;
 208         size_t connect_length, connect_resp_length;
 209         int bytes_recv, ret;
 210
 211         cl = ndev->cl;
 212         dev = cl->dev;
 213
 214         connect_length = sizeof(struct mei_nfc_cmd) +
 215                         sizeof(struct mei_nfc_connect);
 216
 217         connect_resp_length = sizeof(struct mei_nfc_cmd) +
 218                         sizeof(struct mei_nfc_connect_resp);
 219
 220         cmd = kzalloc(connect_length, GFP_KERNEL);
 221         if (!cmd)
 222                 return -ENOMEM;
 223         connect = (struct mei_nfc_connect *)cmd->data;
 224
 225         reply = kzalloc(connect_resp_length, GFP_KERNEL);
 226         if (!reply) {
 227                 kfree(cmd);
 228                 return -ENOMEM;
 229         }
 230
 231         connect_resp = (struct mei_nfc_connect_resp *)reply->data;
 232
 233         cmd->command = MEI_NFC_CMD_MAINTENANCE;
 234         cmd->data_size = 3;
 235         cmd->sub_command = MEI_NFC_SUBCMD_CONNECT;
 236         connect->fw_ivn = ndev->fw_ivn;
 237         connect->vendor_id = ndev->vendor_id;
 238
 239         ret = __mei_cl_send(cl, (u8 *)cmd, connect_length);
 240         if (ret < 0) {
 241                 dev_err(dev->dev, "Could not send connect cmd\n");
 242                 goto err;
 243         }
 244
 245         bytes_recv = __mei_cl_recv(cl, (u8 *)reply, connect_resp_length);
 246         if (bytes_recv < 0) {
 247                 dev_err(dev->dev, "Could not read connect response\n");
 248                 ret = bytes_recv;
 249                 goto err;
 250         }
 251
 252         dev_info(dev->dev, "IVN 0x%x Vendor ID 0x%x\n",
 253                  connect_resp->fw_ivn, connect_resp->vendor_id);
 254
 255         dev_info(dev->dev, "ME FW %d.%d.%d.%d\n",
 256                 connect_resp->me_major, connect_resp->me_minor,
 257                 connect_resp->me_hotfix, connect_resp->me_build);
 258
 259         ret = 0;
 260
 261 err:
 262         kfree(reply);
 263         kfree(cmd);
 264
 265         return ret;
 266 }
 267
 268 static int mei_nfc_if_version(struct mei_nfc_dev *ndev)
 269 {
 270         struct mei_device *dev;
 271         struct mei_cl *cl;
 272
 273         struct mei_nfc_cmd cmd;
 274         struct mei_nfc_reply *reply = NULL;
 275         struct mei_nfc_if_version *version;
 276         size_t if_version_length;
 277         int bytes_recv, ret;
 278
 279         cl = ndev->cl_info;
 280         dev = cl->dev;
 281
 282         memset(&cmd, 0, sizeof(struct mei_nfc_cmd));
 283         cmd.command = MEI_NFC_CMD_MAINTENANCE;
 284         cmd.data_size = 1;
 285         cmd.sub_command = MEI_NFC_SUBCMD_IF_VERSION;
 286
 287         ret = __mei_cl_send(cl, (u8 *)&cmd, sizeof(struct mei_nfc_cmd));
 288         if (ret < 0) {
 289                 dev_err(dev->dev, "Could not send IF version cmd\n");
 290                 return ret;
 291         }
 292
 293         /* to be sure on the stack we alloc memory */
 294         if_version_length = sizeof(struct mei_nfc_reply) +
 295                 sizeof(struct mei_nfc_if_version);
 296
 297         reply = kzalloc(if_version_length, GFP_KERNEL);
 298         if (!reply)
 299                 return -ENOMEM;
 300
 301         bytes_recv = __mei_cl_recv(cl, (u8 *)reply, if_version_length);
 302         if (bytes_recv < 0 || bytes_recv < sizeof(struct mei_nfc_reply)) {
 303                 dev_err(dev->dev, "Could not read IF version\n");
 304                 ret = -EIO;
 305                 goto err;
 306         }
 307
 308         version = (struct mei_nfc_if_version *)reply->data;
 309
 310         ndev->fw_ivn = version->fw_ivn;
 311         ndev->vendor_id = version->vendor_id;
 312         ndev->radio_type = version->radio_type;
 313
 314 err:
 315         kfree(reply);
 316         return ret;
 317 }
 318
 319 static int mei_nfc_enable(struct mei_cl_device *cldev)
 320 {
 321         struct mei_device *dev;
 322         struct mei_nfc_dev *ndev = &nfc_dev;
 323         int ret;
 324
 325         dev = ndev->cl->dev;
 326
 327         ret = mei_nfc_connect(ndev);
 328         if (ret < 0) {
 329                 dev_err(dev->dev, "Could not connect to NFC");
 330                 return ret;
 331         }
 332
 333         return 0;
 334 }
 335
 336 static int mei_nfc_disable(struct mei_cl_device *cldev)
 337 {
 338         return 0;
 339 }
 340
 341 static int mei_nfc_send(struct mei_cl_device *cldev, u8 *buf, size_t length)
 342 {
 343         struct mei_device *dev;
 344         struct mei_nfc_dev *ndev;
 345         struct mei_nfc_hci_hdr *hdr;
 346         u8 *mei_buf;
 347         int err;
 348
 349         ndev = (struct mei_nfc_dev *) cldev->priv_data;
 350         dev = ndev->cl->dev;
 351
 352         err = -ENOMEM;
 353         mei_buf = kzalloc(length + MEI_NFC_HEADER_SIZE, GFP_KERNEL);
 354         if (!mei_buf)
 355                 goto out;
 356
 357         hdr = (struct mei_nfc_hci_hdr *) mei_buf;
 358         hdr->cmd = MEI_NFC_CMD_HCI_SEND;
 359         hdr->status = 0;
 360         hdr->req_id = ndev->req_id;
 361         hdr->reserved = 0;
 362         hdr->data_size = length;
 363
 364         memcpy(mei_buf + MEI_NFC_HEADER_SIZE, buf, length);
 365         err = __mei_cl_send(ndev->cl, mei_buf, length + MEI_NFC_HEADER_SIZE);
 366         if (err < 0)
 367                 goto out;
 368
 369         if (!wait_event_interruptible_timeout(ndev->send_wq,
 370                                 ndev->recv_req_id == ndev->req_id, HZ)) {
 371                 dev_err(dev->dev, "NFC MEI command timeout\n");
 372                 err = -ETIME;
 373         } else {
 374                 ndev->req_id++;
 375         }
 376 out:
 377         kfree(mei_buf);
 378         return err;
 379 }
 380
 381 static int mei_nfc_recv(struct mei_cl_device *cldev, u8 *buf, size_t length)
 382 {
 383         struct mei_nfc_dev *ndev;
 384         struct mei_nfc_hci_hdr *hci_hdr;
 385         int received_length;
 386
 387         ndev = (struct mei_nfc_dev *)cldev->priv_data;
 388
 389         received_length = __mei_cl_recv(ndev->cl, buf, length);
 390         if (received_length < 0)
 391                 return received_length;
 392
 393         hci_hdr = (struct mei_nfc_hci_hdr *) buf;
 394
 395         if (hci_hdr->cmd == MEI_NFC_CMD_HCI_SEND) {
 396                 ndev->recv_req_id = hci_hdr->req_id;
 397                 wake_up(&ndev->send_wq);
 398
 399                 return 0;
 400         }
 401
 402         return received_length;
 403 }
 404
 405 static struct mei_cl_ops nfc_ops = {
 406         .enable = mei_nfc_enable,
 407         .disable = mei_nfc_disable,
 408         .send = mei_nfc_send,
 409         .recv = mei_nfc_recv,
 410 };
 411
 412 static void mei_nfc_init(struct work_struct *work)
 413 {
 414         struct mei_device *dev;
 415         struct mei_cl_device *cldev;
 416         struct mei_nfc_dev *ndev;
 417         struct mei_cl *cl_info;
 418
 419         ndev = container_of(work, struct mei_nfc_dev, init_work);
 420
 421         cl_info = ndev->cl_info;
 422         dev = cl_info->dev;
 423
 424         mutex_lock(&dev->device_lock);
 425
 426         if (mei_cl_connect(cl_info, NULL) < 0) {
 427                 mutex_unlock(&dev->device_lock);
 428                 dev_err(dev->dev, "Could not connect to the NFC INFO ME client");
 429
 430                 goto err;
 431         }
 432
 433         mutex_unlock(&dev->device_lock);
 434
 435         if (mei_nfc_if_version(ndev) < 0) {
 436                 dev_err(dev->dev, "Could not get the NFC interface version");
 437
 438                 goto err;
 439         }
 440
 441         dev_info(dev->dev, "NFC MEI VERSION: IVN 0x%x Vendor ID 0x%x Type 0x%x\n",
 442                 ndev->fw_ivn, ndev->vendor_id, ndev->radio_type);
 443
 444         mutex_lock(&dev->device_lock);
 445
 446         if (mei_cl_disconnect(cl_info) < 0) {
 447                 mutex_unlock(&dev->device_lock);
 448                 dev_err(dev->dev, "Could not disconnect the NFC INFO ME client");
 449
 450                 goto err;
 451         }
 452
 453         mutex_unlock(&dev->device_lock);
 454
 455         if (mei_nfc_build_bus_name(ndev) < 0) {
 456                 dev_err(dev->dev, "Could not build the bus ID name\n");
 457                 return;
 458         }
 459
 460         cldev = mei_cl_add_device(dev, mei_nfc_guid, ndev->bus_name, &nfc_ops);
 461         if (!cldev) {
 462                 dev_err(dev->dev, "Could not add the NFC device to the MEI bus\n");
 463
 464                 goto err;
 465         }
 466
 467         cldev->priv_data = ndev;
 468
 469
 470         return;
 471
 472 err:
 473         mutex_lock(&dev->device_lock);
 474         mei_nfc_free(ndev);
 475         mutex_unlock(&dev->device_lock);
 476
 477 }
 478
 479
 480 int mei_nfc_host_init(struct mei_device *dev)
 481 {
 482         struct mei_nfc_dev *ndev = &nfc_dev;
 483         struct mei_cl *cl_info, *cl = NULL;
 484         struct mei_me_client *me_cl;
 485         int ret;
 486
 487         /* already initialized */
 488         if (ndev->cl_info)
 489                 return 0;
 490
 491         ndev->cl_info = mei_cl_allocate(dev);
 492         ndev->cl = mei_cl_allocate(dev);
 493
 494         cl = ndev->cl;
 495         cl_info = ndev->cl_info;
 496
 497         if (!cl || !cl_info) {
 498                 ret = -ENOMEM;
 499                 goto err;
 500         }
 501
 502         /* check for valid client id */
 503         me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_info_guid);
 504         if (!me_cl) {
 505                 dev_info(dev->dev, "nfc: failed to find the client\n");
 506                 ret = -ENOTTY;
 507                 goto err;
 508         }
 509
 510         cl_info->me_client_id = me_cl->client_id;
 511         cl_info->cl_uuid = me_cl->props.protocol_name;
 512
 513         ret = mei_cl_link(cl_info, MEI_HOST_CLIENT_ID_ANY);
 514         if (ret)
 515                 goto err;
 516
 517
 518         list_add_tail(&cl_info->device_link, &dev->device_list);
 519
 520         /* check for valid client id */
 521         me_cl = mei_me_cl_by_uuid(dev, &mei_nfc_guid);
 522         if (!me_cl) {
 523                 dev_info(dev->dev, "nfc: failed to find the client\n");
 524                 ret = -ENOTTY;
 525                 goto err;
 526         }
 527
 528         cl->me_client_id = me_cl->client_id;
 529         cl->cl_uuid = me_cl->props.protocol_name;
 530
 531         ret = mei_cl_link(cl, MEI_HOST_CLIENT_ID_ANY);
 532         if (ret)
 533                 goto err;
 534
 535         list_add_tail(&cl->device_link, &dev->device_list);
 536
 537         ndev->req_id = 1;
 538
 539         INIT_WORK(&ndev->init_work, mei_nfc_init);
 540         init_waitqueue_head(&ndev->send_wq);
 541         schedule_work(&ndev->init_work);
 542
 543         return 0;
 544
 545 err:
 546         mei_nfc_free(ndev);
 547
 548         return ret;
 549 }
 550
 551 void mei_nfc_host_exit(struct mei_device *dev)
 552 {
 553         struct mei_nfc_dev *ndev = &nfc_dev;
 554
 555         cancel_work_sync(&ndev->init_work);
 556 }
 557
 558