git.oblomov.eu Git - linux-2.6/blob - drivers/char/tpm/tpm.c

   1 /*
   2  * Copyright (C) 2004 IBM Corporation
   3  *
   4  * Authors:
   5  * Leendert van Doorn <leendert@watson.ibm.com>
   6  * Dave Safford <safford@watson.ibm.com>
   7  * Reiner Sailer <sailer@watson.ibm.com>
   8  * Kylene Hall <kjhall@us.ibm.com>
   9  *
  10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  11  *
  12  * Device driver for TCG/TCPA TPM (trusted platform module).
  13  * Specifications at www.trustedcomputinggroup.org
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License as
  17  * published by the Free Software Foundation, version 2 of the
  18  * License.
  19  *
  20  * Note, the TPM chip is not interrupt driven (only polling)
  21  * and can have very long timeouts (minutes!). Hence the unusual
  22  * calls to msleep.
  23  *
  24  */
  25
  26 #include <linux/poll.h>
  27 #include <linux/mutex.h>
  28 #include <linux/spinlock.h>
  29 #include <linux/smp_lock.h>
  30
  31 #include "tpm.h"
  32
  33 enum tpm_const {
  34         TPM_MINOR = 224,        /* officially assigned */
  35         TPM_BUFSIZE = 2048,
  36         TPM_NUM_DEVICES = 256,
  37 };
  38
  39 enum tpm_duration {
  40         TPM_SHORT = 0,
  41         TPM_MEDIUM = 1,
  42         TPM_LONG = 2,
  43         TPM_UNDEFINED,
  44 };
  45
  46 #define TPM_MAX_ORDINAL 243
  47 #define TPM_MAX_PROTECTED_ORDINAL 12
  48 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
  49
  50 static LIST_HEAD(tpm_chip_list);
  51 static DEFINE_SPINLOCK(driver_lock);
  52 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  53
  54 /*
  55  * Array with one entry per ordinal defining the maximum amount
  56  * of time the chip could take to return the result.  The ordinal
  57  * designation of short, medium or long is defined in a table in
  58  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  59  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  60  * from the chip during initialization with a call to tpm_get_timeouts.
  61  */
  62 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
  63         TPM_UNDEFINED,          /* 0 */
  64         TPM_UNDEFINED,
  65         TPM_UNDEFINED,
  66         TPM_UNDEFINED,
  67         TPM_UNDEFINED,
  68         TPM_UNDEFINED,          /* 5 */
  69         TPM_UNDEFINED,
  70         TPM_UNDEFINED,
  71         TPM_UNDEFINED,
  72         TPM_UNDEFINED,
  73         TPM_SHORT,              /* 10 */
  74         TPM_SHORT,
  75 };
  76
  77 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  78         TPM_UNDEFINED,          /* 0 */
  79         TPM_UNDEFINED,
  80         TPM_UNDEFINED,
  81         TPM_UNDEFINED,
  82         TPM_UNDEFINED,
  83         TPM_UNDEFINED,          /* 5 */
  84         TPM_UNDEFINED,
  85         TPM_UNDEFINED,
  86         TPM_UNDEFINED,
  87         TPM_UNDEFINED,
  88         TPM_SHORT,              /* 10 */
  89         TPM_SHORT,
  90         TPM_MEDIUM,
  91         TPM_LONG,
  92         TPM_LONG,
  93         TPM_MEDIUM,             /* 15 */
  94         TPM_SHORT,
  95         TPM_SHORT,
  96         TPM_MEDIUM,
  97         TPM_LONG,
  98         TPM_SHORT,              /* 20 */
  99         TPM_SHORT,
 100         TPM_MEDIUM,
 101         TPM_MEDIUM,
 102         TPM_MEDIUM,
 103         TPM_SHORT,              /* 25 */
 104         TPM_SHORT,
 105         TPM_MEDIUM,
 106         TPM_SHORT,
 107         TPM_SHORT,
 108         TPM_MEDIUM,             /* 30 */
 109         TPM_LONG,
 110         TPM_MEDIUM,
 111         TPM_SHORT,
 112         TPM_SHORT,
 113         TPM_SHORT,              /* 35 */
 114         TPM_MEDIUM,
 115         TPM_MEDIUM,
 116         TPM_UNDEFINED,
 117         TPM_UNDEFINED,
 118         TPM_MEDIUM,             /* 40 */
 119         TPM_LONG,
 120         TPM_MEDIUM,
 121         TPM_SHORT,
 122         TPM_SHORT,
 123         TPM_SHORT,              /* 45 */
 124         TPM_SHORT,
 125         TPM_SHORT,
 126         TPM_SHORT,
 127         TPM_LONG,
 128         TPM_MEDIUM,             /* 50 */
 129         TPM_MEDIUM,
 130         TPM_UNDEFINED,
 131         TPM_UNDEFINED,
 132         TPM_UNDEFINED,
 133         TPM_UNDEFINED,          /* 55 */
 134         TPM_UNDEFINED,
 135         TPM_UNDEFINED,
 136         TPM_UNDEFINED,
 137         TPM_UNDEFINED,
 138         TPM_MEDIUM,             /* 60 */
 139         TPM_MEDIUM,
 140         TPM_MEDIUM,
 141         TPM_SHORT,
 142         TPM_SHORT,
 143         TPM_MEDIUM,             /* 65 */
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_SHORT,              /* 70 */
 149         TPM_SHORT,
 150         TPM_UNDEFINED,
 151         TPM_UNDEFINED,
 152         TPM_UNDEFINED,
 153         TPM_UNDEFINED,          /* 75 */
 154         TPM_UNDEFINED,
 155         TPM_UNDEFINED,
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_LONG,               /* 80 */
 159         TPM_UNDEFINED,
 160         TPM_MEDIUM,
 161         TPM_LONG,
 162         TPM_SHORT,
 163         TPM_UNDEFINED,          /* 85 */
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_SHORT,              /* 90 */
 169         TPM_SHORT,
 170         TPM_SHORT,
 171         TPM_SHORT,
 172         TPM_SHORT,
 173         TPM_UNDEFINED,          /* 95 */
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_MEDIUM,             /* 100 */
 179         TPM_SHORT,
 180         TPM_SHORT,
 181         TPM_UNDEFINED,
 182         TPM_UNDEFINED,
 183         TPM_UNDEFINED,          /* 105 */
 184         TPM_UNDEFINED,
 185         TPM_UNDEFINED,
 186         TPM_UNDEFINED,
 187         TPM_UNDEFINED,
 188         TPM_SHORT,              /* 110 */
 189         TPM_SHORT,
 190         TPM_SHORT,
 191         TPM_SHORT,
 192         TPM_SHORT,
 193         TPM_SHORT,              /* 115 */
 194         TPM_SHORT,
 195         TPM_SHORT,
 196         TPM_UNDEFINED,
 197         TPM_UNDEFINED,
 198         TPM_LONG,               /* 120 */
 199         TPM_LONG,
 200         TPM_MEDIUM,
 201         TPM_UNDEFINED,
 202         TPM_SHORT,
 203         TPM_SHORT,              /* 125 */
 204         TPM_SHORT,
 205         TPM_LONG,
 206         TPM_SHORT,
 207         TPM_SHORT,
 208         TPM_SHORT,              /* 130 */
 209         TPM_MEDIUM,
 210         TPM_UNDEFINED,
 211         TPM_SHORT,
 212         TPM_MEDIUM,
 213         TPM_UNDEFINED,          /* 135 */
 214         TPM_UNDEFINED,
 215         TPM_UNDEFINED,
 216         TPM_UNDEFINED,
 217         TPM_UNDEFINED,
 218         TPM_SHORT,              /* 140 */
 219         TPM_SHORT,
 220         TPM_UNDEFINED,
 221         TPM_UNDEFINED,
 222         TPM_UNDEFINED,
 223         TPM_UNDEFINED,          /* 145 */
 224         TPM_UNDEFINED,
 225         TPM_UNDEFINED,
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_SHORT,              /* 150 */
 229         TPM_MEDIUM,
 230         TPM_MEDIUM,
 231         TPM_SHORT,
 232         TPM_SHORT,
 233         TPM_UNDEFINED,          /* 155 */
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_SHORT,              /* 160 */
 239         TPM_SHORT,
 240         TPM_SHORT,
 241         TPM_SHORT,
 242         TPM_UNDEFINED,
 243         TPM_UNDEFINED,          /* 165 */
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_LONG,               /* 170 */
 249         TPM_UNDEFINED,
 250         TPM_UNDEFINED,
 251         TPM_UNDEFINED,
 252         TPM_UNDEFINED,
 253         TPM_UNDEFINED,          /* 175 */
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,
 256         TPM_UNDEFINED,
 257         TPM_UNDEFINED,
 258         TPM_MEDIUM,             /* 180 */
 259         TPM_SHORT,
 260         TPM_MEDIUM,
 261         TPM_MEDIUM,
 262         TPM_MEDIUM,
 263         TPM_MEDIUM,             /* 185 */
 264         TPM_SHORT,
 265         TPM_UNDEFINED,
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_UNDEFINED,          /* 190 */
 269         TPM_UNDEFINED,
 270         TPM_UNDEFINED,
 271         TPM_UNDEFINED,
 272         TPM_UNDEFINED,
 273         TPM_UNDEFINED,          /* 195 */
 274         TPM_UNDEFINED,
 275         TPM_UNDEFINED,
 276         TPM_UNDEFINED,
 277         TPM_UNDEFINED,
 278         TPM_SHORT,              /* 200 */
 279         TPM_UNDEFINED,
 280         TPM_UNDEFINED,
 281         TPM_UNDEFINED,
 282         TPM_SHORT,
 283         TPM_SHORT,              /* 205 */
 284         TPM_SHORT,
 285         TPM_SHORT,
 286         TPM_SHORT,
 287         TPM_SHORT,
 288         TPM_MEDIUM,             /* 210 */
 289         TPM_UNDEFINED,
 290         TPM_MEDIUM,
 291         TPM_MEDIUM,
 292         TPM_MEDIUM,
 293         TPM_UNDEFINED,          /* 215 */
 294         TPM_MEDIUM,
 295         TPM_UNDEFINED,
 296         TPM_UNDEFINED,
 297         TPM_SHORT,
 298         TPM_SHORT,              /* 220 */
 299         TPM_SHORT,
 300         TPM_SHORT,
 301         TPM_SHORT,
 302         TPM_SHORT,
 303         TPM_UNDEFINED,          /* 225 */
 304         TPM_UNDEFINED,
 305         TPM_UNDEFINED,
 306         TPM_UNDEFINED,
 307         TPM_UNDEFINED,
 308         TPM_SHORT,              /* 230 */
 309         TPM_LONG,
 310         TPM_MEDIUM,
 311         TPM_UNDEFINED,
 312         TPM_UNDEFINED,
 313         TPM_UNDEFINED,          /* 235 */
 314         TPM_UNDEFINED,
 315         TPM_UNDEFINED,
 316         TPM_UNDEFINED,
 317         TPM_UNDEFINED,
 318         TPM_SHORT,              /* 240 */
 319         TPM_UNDEFINED,
 320         TPM_MEDIUM,
 321 };
 322
 323 static void user_reader_timeout(unsigned long ptr)
 324 {
 325         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 326
 327         schedule_work(&chip->work);
 328 }
 329
 330 static void timeout_work(struct work_struct *work)
 331 {
 332         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 333
 334         mutex_lock(&chip->buffer_mutex);
 335         atomic_set(&chip->data_pending, 0);
 336         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 337         mutex_unlock(&chip->buffer_mutex);
 338 }
 339
 340 /*
 341  * Returns max number of jiffies to wait
 342  */
 343 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 344                                            u32 ordinal)
 345 {
 346         int duration_idx = TPM_UNDEFINED;
 347         int duration = 0;
 348
 349         if (ordinal < TPM_MAX_ORDINAL)
 350                 duration_idx = tpm_ordinal_duration[ordinal];
 351         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 352                  TPM_MAX_PROTECTED_ORDINAL)
 353                 duration_idx =
 354                     tpm_protected_ordinal_duration[ordinal &
 355                                                    TPM_PROTECTED_ORDINAL_MASK];
 356
 357         if (duration_idx != TPM_UNDEFINED)
 358                 duration = chip->vendor.duration[duration_idx];
 359         if (duration <= 0)
 360                 return 2 * 60 * HZ;
 361         else
 362                 return duration;
 363 }
 364 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 365
 366 /*
 367  * Internal kernel interface to transmit TPM commands
 368  */
 369 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 370                             size_t bufsiz)
 371 {
 372         ssize_t rc;
 373         u32 count, ordinal;
 374         unsigned long stop;
 375
 376         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 377         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 378         if (count == 0)
 379                 return -ENODATA;
 380         if (count > bufsiz) {
 381                 dev_err(chip->dev,
 382                         "invalid count value %x %zx \n", count, bufsiz);
 383                 return -E2BIG;
 384         }
 385
 386         mutex_lock(&chip->tpm_mutex);
 387
 388         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 389                 dev_err(chip->dev,
 390                         "tpm_transmit: tpm_send: error %zd\n", rc);
 391                 goto out;
 392         }
 393
 394         if (chip->vendor.irq)
 395                 goto out_recv;
 396
 397         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 398         do {
 399                 u8 status = chip->vendor.status(chip);
 400                 if ((status & chip->vendor.req_complete_mask) ==
 401                     chip->vendor.req_complete_val)
 402                         goto out_recv;
 403
 404                 if ((status == chip->vendor.req_canceled)) {
 405                         dev_err(chip->dev, "Operation Canceled\n");
 406                         rc = -ECANCELED;
 407                         goto out;
 408                 }
 409
 410                 msleep(TPM_TIMEOUT);    /* CHECK */
 411                 rmb();
 412         } while (time_before(jiffies, stop));
 413
 414         chip->vendor.cancel(chip);
 415         dev_err(chip->dev, "Operation Timed out\n");
 416         rc = -ETIME;
 417         goto out;
 418
 419 out_recv:
 420         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 421         if (rc < 0)
 422                 dev_err(chip->dev,
 423                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 424 out:
 425         mutex_unlock(&chip->tpm_mutex);
 426         return rc;
 427 }
 428
 429 #define TPM_DIGEST_SIZE 20
 430 #define TPM_ERROR_SIZE 10
 431 #define TPM_RET_CODE_IDX 6
 432 #define TPM_GET_CAP_RET_SIZE_IDX 10
 433 #define TPM_GET_CAP_RET_UINT32_1_IDX 14
 434 #define TPM_GET_CAP_RET_UINT32_2_IDX 18
 435 #define TPM_GET_CAP_RET_UINT32_3_IDX 22
 436 #define TPM_GET_CAP_RET_UINT32_4_IDX 26
 437 #define TPM_GET_CAP_PERM_DISABLE_IDX 16
 438 #define TPM_GET_CAP_PERM_INACTIVE_IDX 18
 439 #define TPM_GET_CAP_RET_BOOL_1_IDX 14
 440 #define TPM_GET_CAP_TEMP_INACTIVE_IDX 16
 441
 442 #define TPM_CAP_IDX 13
 443 #define TPM_CAP_SUBCAP_IDX 21
 444
 445 enum tpm_capabilities {
 446         TPM_CAP_FLAG = 4,
 447         TPM_CAP_PROP = 5,
 448 };
 449
 450 enum tpm_sub_capabilities {
 451         TPM_CAP_PROP_PCR = 0x1,
 452         TPM_CAP_PROP_MANUFACTURER = 0x3,
 453         TPM_CAP_FLAG_PERM = 0x8,
 454         TPM_CAP_FLAG_VOL = 0x9,
 455         TPM_CAP_PROP_OWNER = 0x11,
 456         TPM_CAP_PROP_TIS_TIMEOUT = 0x15,
 457         TPM_CAP_PROP_TIS_DURATION = 0x20,
 458 };
 459
 460 /*
 461  * This is a semi generic GetCapability command for use
 462  * with the capability type TPM_CAP_PROP or TPM_CAP_FLAG
 463  * and their associated sub_capabilities.
 464  */
 465
 466 static const u8 tpm_cap[] = {
 467         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 468         0, 0, 0, 22,            /* length */
 469         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 470         0, 0, 0, 0,             /* TPM_CAP_<TYPE> */
 471         0, 0, 0, 4,             /* TPM_CAP_SUB_<TYPE> size */
 472         0, 0, 1, 0              /* TPM_CAP_SUB_<TYPE> */
 473 };
 474
 475 static ssize_t transmit_cmd(struct tpm_chip *chip, u8 *data, int len,
 476                             char *desc)
 477 {
 478         int err;
 479
 480         len = tpm_transmit(chip, data, len);
 481         if (len <  0)
 482                 return len;
 483         if (len == TPM_ERROR_SIZE) {
 484                 err = be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX)));
 485                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 486                 return err;
 487         }
 488         return 0;
 489 }
 490
 491 void tpm_gen_interrupt(struct tpm_chip *chip)
 492 {
 493         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
 494         ssize_t rc;
 495
 496         memcpy(data, tpm_cap, sizeof(tpm_cap));
 497         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 498         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
 499
 500         rc = transmit_cmd(chip, data, sizeof(data),
 501                         "attempting to determine the timeouts");
 502 }
 503 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 504
 505 void tpm_get_timeouts(struct tpm_chip *chip)
 506 {
 507         u8 data[max_t(int, ARRAY_SIZE(tpm_cap), 30)];
 508         ssize_t rc;
 509         u32 timeout;
 510
 511         memcpy(data, tpm_cap, sizeof(tpm_cap));
 512         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 513         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_TIMEOUT;
 514
 515         rc = transmit_cmd(chip, data, sizeof(data),
 516                         "attempting to determine the timeouts");
 517         if (rc)
 518                 goto duration;
 519
 520         if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
 521             != 4 * sizeof(u32))
 522                 goto duration;
 523
 524         /* Don't overwrite default if value is 0 */
 525         timeout =
 526             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX)));
 527         if (timeout)
 528                 chip->vendor.timeout_a = msecs_to_jiffies(timeout);
 529         timeout =
 530             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_2_IDX)));
 531         if (timeout)
 532                 chip->vendor.timeout_b = msecs_to_jiffies(timeout);
 533         timeout =
 534             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_3_IDX)));
 535         if (timeout)
 536                 chip->vendor.timeout_c = msecs_to_jiffies(timeout);
 537         timeout =
 538             be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_4_IDX)));
 539         if (timeout)
 540                 chip->vendor.timeout_d = msecs_to_jiffies(timeout);
 541
 542 duration:
 543         memcpy(data, tpm_cap, sizeof(tpm_cap));
 544         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 545         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_TIS_DURATION;
 546
 547         rc = transmit_cmd(chip, data, sizeof(data),
 548                         "attempting to determine the durations");
 549         if (rc)
 550                 return;
 551
 552         if (be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_SIZE_IDX)))
 553             != 3 * sizeof(u32))
 554                 return;
 555
 556         chip->vendor.duration[TPM_SHORT] =
 557             msecs_to_jiffies(be32_to_cpu
 558                              (*((__be32 *) (data +
 559                                             TPM_GET_CAP_RET_UINT32_1_IDX))));
 560         chip->vendor.duration[TPM_MEDIUM] =
 561             msecs_to_jiffies(be32_to_cpu
 562                              (*((__be32 *) (data +
 563                                             TPM_GET_CAP_RET_UINT32_2_IDX))));
 564         chip->vendor.duration[TPM_LONG] =
 565             msecs_to_jiffies(be32_to_cpu
 566                              (*((__be32 *) (data +
 567                                             TPM_GET_CAP_RET_UINT32_3_IDX))));
 568 }
 569 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 570
 571 void tpm_continue_selftest(struct tpm_chip *chip)
 572 {
 573         u8 data[] = {
 574                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 575                 0, 0, 0, 10,            /* length */
 576                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
 577         };
 578
 579         tpm_transmit(chip, data, sizeof(data));
 580 }
 581 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 582
 583 #define  TPM_INTERNAL_RESULT_SIZE 200
 584
 585 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 586                         char *buf)
 587 {
 588         u8 *data;
 589         ssize_t rc;
 590
 591         struct tpm_chip *chip = dev_get_drvdata(dev);
 592         if (chip == NULL)
 593                 return -ENODEV;
 594
 595         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 596         if (!data)
 597                 return -ENOMEM;
 598
 599         memcpy(data, tpm_cap, sizeof(tpm_cap));
 600         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 601         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
 602
 603         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 604                         "attemtping to determine the permanent enabled state");
 605         if (rc) {
 606                 kfree(data);
 607                 return 0;
 608         }
 609
 610         rc = sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_DISABLE_IDX]);
 611
 612         kfree(data);
 613         return rc;
 614 }
 615 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 616
 617 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 618                         char *buf)
 619 {
 620         u8 *data;
 621         ssize_t rc;
 622
 623         struct tpm_chip *chip = dev_get_drvdata(dev);
 624         if (chip == NULL)
 625                 return -ENODEV;
 626
 627         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 628         if (!data)
 629                 return -ENOMEM;
 630
 631         memcpy(data, tpm_cap, sizeof(tpm_cap));
 632         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 633         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_PERM;
 634
 635         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 636                         "attemtping to determine the permanent active state");
 637         if (rc) {
 638                 kfree(data);
 639                 return 0;
 640         }
 641
 642         rc = sprintf(buf, "%d\n", !data[TPM_GET_CAP_PERM_INACTIVE_IDX]);
 643
 644         kfree(data);
 645         return rc;
 646 }
 647 EXPORT_SYMBOL_GPL(tpm_show_active);
 648
 649 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 650                         char *buf)
 651 {
 652         u8 *data;
 653         ssize_t rc;
 654
 655         struct tpm_chip *chip = dev_get_drvdata(dev);
 656         if (chip == NULL)
 657                 return -ENODEV;
 658
 659         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 660         if (!data)
 661                 return -ENOMEM;
 662
 663         memcpy(data, tpm_cap, sizeof(tpm_cap));
 664         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 665         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_OWNER;
 666
 667         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 668                         "attempting to determine the owner state");
 669         if (rc) {
 670                 kfree(data);
 671                 return 0;
 672         }
 673
 674         rc = sprintf(buf, "%d\n", data[TPM_GET_CAP_RET_BOOL_1_IDX]);
 675
 676         kfree(data);
 677         return rc;
 678 }
 679 EXPORT_SYMBOL_GPL(tpm_show_owned);
 680
 681 ssize_t tpm_show_temp_deactivated(struct device * dev,
 682                                 struct device_attribute * attr, char *buf)
 683 {
 684         u8 *data;
 685         ssize_t rc;
 686
 687         struct tpm_chip *chip = dev_get_drvdata(dev);
 688         if (chip == NULL)
 689                 return -ENODEV;
 690
 691         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 692         if (!data)
 693                 return -ENOMEM;
 694
 695         memcpy(data, tpm_cap, sizeof(tpm_cap));
 696         data[TPM_CAP_IDX] = TPM_CAP_FLAG;
 697         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_FLAG_VOL;
 698
 699         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 700                         "attempting to determine the temporary state");
 701         if (rc) {
 702                 kfree(data);
 703                 return 0;
 704         }
 705
 706         rc = sprintf(buf, "%d\n", data[TPM_GET_CAP_TEMP_INACTIVE_IDX]);
 707
 708         kfree(data);
 709         return rc;
 710 }
 711 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 712
 713 static const u8 pcrread[] = {
 714         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 715         0, 0, 0, 14,            /* length */
 716         0, 0, 0, 21,            /* TPM_ORD_PcrRead */
 717         0, 0, 0, 0              /* PCR index */
 718 };
 719
 720 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 721                       char *buf)
 722 {
 723         u8 *data;
 724         ssize_t rc;
 725         int i, j, num_pcrs;
 726         __be32 index;
 727         char *str = buf;
 728
 729         struct tpm_chip *chip = dev_get_drvdata(dev);
 730         if (chip == NULL)
 731                 return -ENODEV;
 732
 733         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 734         if (!data)
 735                 return -ENOMEM;
 736
 737         memcpy(data, tpm_cap, sizeof(tpm_cap));
 738         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 739         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_PCR;
 740
 741         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 742                         "attempting to determine the number of PCRS");
 743         if (rc) {
 744                 kfree(data);
 745                 return 0;
 746         }
 747
 748         num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
 749         for (i = 0; i < num_pcrs; i++) {
 750                 memcpy(data, pcrread, sizeof(pcrread));
 751                 index = cpu_to_be32(i);
 752                 memcpy(data + 10, &index, 4);
 753                 rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 754                                 "attempting to read a PCR");
 755                 if (rc)
 756                         goto out;
 757                 str += sprintf(str, "PCR-%02d: ", i);
 758                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 759                         str += sprintf(str, "%02X ", *(data + 10 + j));
 760                 str += sprintf(str, "\n");
 761         }
 762 out:
 763         kfree(data);
 764         return str - buf;
 765 }
 766 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 767
 768 #define  READ_PUBEK_RESULT_SIZE 314
 769 static const u8 readpubek[] = {
 770         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 771         0, 0, 0, 30,            /* length */
 772         0, 0, 0, 124,           /* TPM_ORD_ReadPubek */
 773 };
 774
 775 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 776                        char *buf)
 777 {
 778         u8 *data;
 779         ssize_t err;
 780         int i, rc;
 781         char *str = buf;
 782
 783         struct tpm_chip *chip = dev_get_drvdata(dev);
 784         if (chip == NULL)
 785                 return -ENODEV;
 786
 787         data = kzalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
 788         if (!data)
 789                 return -ENOMEM;
 790
 791         memcpy(data, readpubek, sizeof(readpubek));
 792
 793         err = transmit_cmd(chip, data, READ_PUBEK_RESULT_SIZE,
 794                         "attempting to read the PUBEK");
 795         if (err)
 796                 goto out;
 797
 798         /*
 799            ignore header 10 bytes
 800            algorithm 32 bits (1 == RSA )
 801            encscheme 16 bits
 802            sigscheme 16 bits
 803            parameters (RSA 12->bytes: keybit, #primes, expbit)
 804            keylenbytes 32 bits
 805            256 byte modulus
 806            ignore checksum 20 bytes
 807          */
 808
 809         str +=
 810             sprintf(str,
 811                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
 812                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
 813                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
 814                     "Modulus length: %d\nModulus: \n",
 815                     data[10], data[11], data[12], data[13], data[14],
 816                     data[15], data[16], data[17], data[22], data[23],
 817                     data[24], data[25], data[26], data[27], data[28],
 818                     data[29], data[30], data[31], data[32], data[33],
 819                     be32_to_cpu(*((__be32 *) (data + 34))));
 820
 821         for (i = 0; i < 256; i++) {
 822                 str += sprintf(str, "%02X ", data[i + 38]);
 823                 if ((i + 1) % 16 == 0)
 824                         str += sprintf(str, "\n");
 825         }
 826 out:
 827         rc = str - buf;
 828         kfree(data);
 829         return rc;
 830 }
 831 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 832
 833 #define CAP_VERSION_1_1 6
 834 #define CAP_VERSION_1_2 0x1A
 835 #define CAP_VERSION_IDX 13
 836 static const u8 cap_version[] = {
 837         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 838         0, 0, 0, 18,            /* length */
 839         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 840         0, 0, 0, 0,
 841         0, 0, 0, 0
 842 };
 843
 844 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 845                       char *buf)
 846 {
 847         u8 *data;
 848         ssize_t rc;
 849         char *str = buf;
 850
 851         struct tpm_chip *chip = dev_get_drvdata(dev);
 852         if (chip == NULL)
 853                 return -ENODEV;
 854
 855         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 856         if (!data)
 857                 return -ENOMEM;
 858
 859         memcpy(data, tpm_cap, sizeof(tpm_cap));
 860         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 861         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 862
 863         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 864                         "attempting to determine the manufacturer");
 865         if (rc) {
 866                 kfree(data);
 867                 return 0;
 868         }
 869
 870         str += sprintf(str, "Manufacturer: 0x%x\n",
 871                        be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 872
 873         memcpy(data, cap_version, sizeof(cap_version));
 874         data[CAP_VERSION_IDX] = CAP_VERSION_1_1;
 875         rc = transmit_cmd(chip, data, TPM_INTERNAL_RESULT_SIZE,
 876                         "attempting to determine the 1.1 version");
 877         if (rc)
 878                 goto out;
 879
 880         str += sprintf(str,
 881                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 882                        (int) data[14], (int) data[15], (int) data[16],
 883                        (int) data[17]);
 884
 885 out:
 886         kfree(data);
 887         return str - buf;
 888 }
 889 EXPORT_SYMBOL_GPL(tpm_show_caps);
 890
 891 ssize_t tpm_show_caps_1_2(struct device * dev,
 892                           struct device_attribute * attr, char *buf)
 893 {
 894         u8 *data;
 895         ssize_t len;
 896         char *str = buf;
 897
 898         struct tpm_chip *chip = dev_get_drvdata(dev);
 899         if (chip == NULL)
 900                 return -ENODEV;
 901
 902         data = kzalloc(TPM_INTERNAL_RESULT_SIZE, GFP_KERNEL);
 903         if (!data)
 904                 return -ENOMEM;
 905
 906         memcpy(data, tpm_cap, sizeof(tpm_cap));
 907         data[TPM_CAP_IDX] = TPM_CAP_PROP;
 908         data[TPM_CAP_SUBCAP_IDX] = TPM_CAP_PROP_MANUFACTURER;
 909
 910         len = tpm_transmit(chip, data, TPM_INTERNAL_RESULT_SIZE);
 911         if (len <= TPM_ERROR_SIZE) {
 912                 dev_dbg(chip->dev, "A TPM error (%d) occurred "
 913                         "attempting to determine the manufacturer\n",
 914                         be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
 915                 kfree(data);
 916                 return 0;
 917         }
 918
 919         str += sprintf(str, "Manufacturer: 0x%x\n",
 920                        be32_to_cpu(*((__be32 *) (data + TPM_GET_CAP_RET_UINT32_1_IDX))));
 921
 922         memcpy(data, cap_version, sizeof(cap_version));
 923         data[CAP_VERSION_IDX] = CAP_VERSION_1_2;
 924
 925         len = tpm_transmit(chip, data, TPM_INTERNAL_RESULT_SIZE);
 926         if (len <= TPM_ERROR_SIZE) {
 927                 dev_err(chip->dev, "A TPM error (%d) occurred "
 928                         "attempting to determine the 1.2 version\n",
 929                         be32_to_cpu(*((__be32 *) (data + TPM_RET_CODE_IDX))));
 930                 goto out;
 931         }
 932         str += sprintf(str,
 933                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 934                        (int) data[16], (int) data[17], (int) data[18],
 935                        (int) data[19]);
 936
 937 out:
 938         kfree(data);
 939         return str - buf;
 940 }
 941 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 942
 943 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 944                         const char *buf, size_t count)
 945 {
 946         struct tpm_chip *chip = dev_get_drvdata(dev);
 947         if (chip == NULL)
 948                 return 0;
 949
 950         chip->vendor.cancel(chip);
 951         return count;
 952 }
 953 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 954
 955 /*
 956  * Device file system interface to the TPM
 957  */
 958 int tpm_open(struct inode *inode, struct file *file)
 959 {
 960         int rc = 0, minor = iminor(inode);
 961         struct tpm_chip *chip = NULL, *pos;
 962
 963         lock_kernel();
 964         spin_lock(&driver_lock);
 965
 966         list_for_each_entry(pos, &tpm_chip_list, list) {
 967                 if (pos->vendor.miscdev.minor == minor) {
 968                         chip = pos;
 969                         break;
 970                 }
 971         }
 972
 973         if (chip == NULL) {
 974                 rc = -ENODEV;
 975                 goto err_out;
 976         }
 977
 978         if (chip->num_opens) {
 979                 dev_dbg(chip->dev, "Another process owns this TPM\n");
 980                 rc = -EBUSY;
 981                 goto err_out;
 982         }
 983
 984         chip->num_opens++;
 985         get_device(chip->dev);
 986
 987         spin_unlock(&driver_lock);
 988
 989         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 990         if (chip->data_buffer == NULL) {
 991                 chip->num_opens--;
 992                 put_device(chip->dev);
 993                 unlock_kernel();
 994                 return -ENOMEM;
 995         }
 996
 997         atomic_set(&chip->data_pending, 0);
 998
 999         file->private_data = chip;
1000         unlock_kernel();
1001         return 0;
1002
1003 err_out:
1004         spin_unlock(&driver_lock);
1005         unlock_kernel();
1006         return rc;
1007 }
1008 EXPORT_SYMBOL_GPL(tpm_open);
1009
1010 int tpm_release(struct inode *inode, struct file *file)
1011 {
1012         struct tpm_chip *chip = file->private_data;
1013
1014         flush_scheduled_work();
1015         spin_lock(&driver_lock);
1016         file->private_data = NULL;
1017         del_singleshot_timer_sync(&chip->user_read_timer);
1018         atomic_set(&chip->data_pending, 0);
1019         chip->num_opens--;
1020         put_device(chip->dev);
1021         kfree(chip->data_buffer);
1022         spin_unlock(&driver_lock);
1023         return 0;
1024 }
1025 EXPORT_SYMBOL_GPL(tpm_release);
1026
1027 ssize_t tpm_write(struct file *file, const char __user *buf,
1028                   size_t size, loff_t *off)
1029 {
1030         struct tpm_chip *chip = file->private_data;
1031         size_t in_size = size, out_size;
1032
1033         /* cannot perform a write until the read has cleared
1034            either via tpm_read or a user_read_timer timeout */
1035         while (atomic_read(&chip->data_pending) != 0)
1036                 msleep(TPM_TIMEOUT);
1037
1038         mutex_lock(&chip->buffer_mutex);
1039
1040         if (in_size > TPM_BUFSIZE)
1041                 in_size = TPM_BUFSIZE;
1042
1043         if (copy_from_user
1044             (chip->data_buffer, (void __user *) buf, in_size)) {
1045                 mutex_unlock(&chip->buffer_mutex);
1046                 return -EFAULT;
1047         }
1048
1049         /* atomic tpm command send and result receive */
1050         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1051
1052         atomic_set(&chip->data_pending, out_size);
1053         mutex_unlock(&chip->buffer_mutex);
1054
1055         /* Set a timeout by which the reader must come claim the result */
1056         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1057
1058         return in_size;
1059 }
1060 EXPORT_SYMBOL_GPL(tpm_write);
1061
1062 ssize_t tpm_read(struct file *file, char __user *buf,
1063                  size_t size, loff_t *off)
1064 {
1065         struct tpm_chip *chip = file->private_data;
1066         ssize_t ret_size;
1067
1068         del_singleshot_timer_sync(&chip->user_read_timer);
1069         flush_scheduled_work();
1070         ret_size = atomic_read(&chip->data_pending);
1071         atomic_set(&chip->data_pending, 0);
1072         if (ret_size > 0) {     /* relay data */
1073                 if (size < ret_size)
1074                         ret_size = size;
1075
1076                 mutex_lock(&chip->buffer_mutex);
1077                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1078                         ret_size = -EFAULT;
1079                 mutex_unlock(&chip->buffer_mutex);
1080         }
1081
1082         return ret_size;
1083 }
1084 EXPORT_SYMBOL_GPL(tpm_read);
1085
1086 void tpm_remove_hardware(struct device *dev)
1087 {
1088         struct tpm_chip *chip = dev_get_drvdata(dev);
1089
1090         if (chip == NULL) {
1091                 dev_err(dev, "No device data found\n");
1092                 return;
1093         }
1094
1095         spin_lock(&driver_lock);
1096
1097         list_del(&chip->list);
1098
1099         spin_unlock(&driver_lock);
1100
1101         misc_deregister(&chip->vendor.miscdev);
1102
1103         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1104         tpm_bios_log_teardown(chip->bios_dir);
1105
1106         /* write it this way to be explicit (chip->dev == dev) */
1107         put_device(chip->dev);
1108 }
1109 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1110
1111 /*
1112  * We are about to suspend. Save the TPM state
1113  * so that it can be restored.
1114  */
1115 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1116 {
1117         struct tpm_chip *chip = dev_get_drvdata(dev);
1118         u8 savestate[] = {
1119                 0, 193,         /* TPM_TAG_RQU_COMMAND */
1120                 0, 0, 0, 10,    /* blob length (in bytes) */
1121                 0, 0, 0, 152    /* TPM_ORD_SaveState */
1122         };
1123
1124         if (chip == NULL)
1125                 return -ENODEV;
1126
1127         tpm_transmit(chip, savestate, sizeof(savestate));
1128         return 0;
1129 }
1130 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1131
1132 /*
1133  * Resume from a power safe. The BIOS already restored
1134  * the TPM state.
1135  */
1136 int tpm_pm_resume(struct device *dev)
1137 {
1138         struct tpm_chip *chip = dev_get_drvdata(dev);
1139
1140         if (chip == NULL)
1141                 return -ENODEV;
1142
1143         return 0;
1144 }
1145 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1146
1147 /*
1148  * Once all references to platform device are down to 0,
1149  * release all allocated structures.
1150  * In case vendor provided release function,
1151  * call it too.
1152  */
1153 static void tpm_dev_release(struct device *dev)
1154 {
1155         struct tpm_chip *chip = dev_get_drvdata(dev);
1156
1157         if (chip->vendor.release)
1158                 chip->vendor.release(dev);
1159
1160         chip->release(dev);
1161
1162         clear_bit(chip->dev_num, dev_mask);
1163         kfree(chip->vendor.miscdev.name);
1164         kfree(chip);
1165 }
1166
1167 /*
1168  * Called from tpm_<specific>.c probe function only for devices
1169  * the driver has determined it should claim.  Prior to calling
1170  * this function the specific probe function has called pci_enable_device
1171  * upon errant exit from this function specific probe function should call
1172  * pci_disable_device
1173  */
1174 struct tpm_chip *tpm_register_hardware(struct device *dev, const struct tpm_vendor_specific
1175                                        *entry)
1176 {
1177 #define DEVNAME_SIZE 7
1178
1179         char *devname;
1180         struct tpm_chip *chip;
1181
1182         /* Driver specific per-device data */
1183         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1184         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1185
1186         if (chip == NULL || devname == NULL) {
1187                 kfree(chip);
1188                 kfree(devname);
1189                 return NULL;
1190         }
1191
1192         mutex_init(&chip->buffer_mutex);
1193         mutex_init(&chip->tpm_mutex);
1194         INIT_LIST_HEAD(&chip->list);
1195
1196         INIT_WORK(&chip->work, timeout_work);
1197
1198         setup_timer(&chip->user_read_timer, user_reader_timeout,
1199                         (unsigned long)chip);
1200
1201         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1202
1203         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1204
1205         if (chip->dev_num >= TPM_NUM_DEVICES) {
1206                 dev_err(dev, "No available tpm device numbers\n");
1207                 kfree(chip);
1208                 return NULL;
1209         } else if (chip->dev_num == 0)
1210                 chip->vendor.miscdev.minor = TPM_MINOR;
1211         else
1212                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1213
1214         set_bit(chip->dev_num, dev_mask);
1215
1216         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1217         chip->vendor.miscdev.name = devname;
1218
1219         chip->vendor.miscdev.parent = dev;
1220         chip->dev = get_device(dev);
1221         chip->release = dev->release;
1222         dev->release = tpm_dev_release;
1223         dev_set_drvdata(dev, chip);
1224
1225         if (misc_register(&chip->vendor.miscdev)) {
1226                 dev_err(chip->dev,
1227                         "unable to misc_register %s, minor %d\n",
1228                         chip->vendor.miscdev.name,
1229                         chip->vendor.miscdev.minor);
1230                 put_device(chip->dev);
1231                 return NULL;
1232         }
1233
1234         spin_lock(&driver_lock);
1235
1236         list_add(&chip->list, &tpm_chip_list);
1237
1238         spin_unlock(&driver_lock);
1239
1240         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1241                 list_del(&chip->list);
1242                 misc_deregister(&chip->vendor.miscdev);
1243                 put_device(chip->dev);
1244                 return NULL;
1245         }
1246
1247         chip->bios_dir = tpm_bios_log_setup(devname);
1248
1249         return chip;
1250 }
1251 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1252
1253 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1254 MODULE_DESCRIPTION("TPM Driver");
1255 MODULE_VERSION("2.0");
1256 MODULE_LICENSE("GPL");