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/slab.h>
  28 #include <linux/mutex.h>
  29 #include <linux/spinlock.h>
  30
  31 #include "tpm.h"
  32
  33 enum tpm_const {
  34         TPM_MINOR = 224,        /* officially assigned */
  35         TPM_BUFSIZE = 4096,
  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 /*
  51  * Bug workaround - some TPM's don't flush the most
  52  * recently changed pcr on suspend, so force the flush
  53  * with an extend to the selected _unused_ non-volatile pcr.
  54  */
  55 static int tpm_suspend_pcr;
  56 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  57 MODULE_PARM_DESC(suspend_pcr,
  58                  "PCR to use for dummy writes to faciltate flush on suspend.");
  59
  60 static LIST_HEAD(tpm_chip_list);
  61 static DEFINE_SPINLOCK(driver_lock);
  62 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  63
  64 /*
  65  * Array with one entry per ordinal defining the maximum amount
  66  * of time the chip could take to return the result.  The ordinal
  67  * designation of short, medium or long is defined in a table in
  68  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  69  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  70  * from the chip during initialization with a call to tpm_get_timeouts.
  71  */
  72 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
  73         TPM_UNDEFINED,          /* 0 */
  74         TPM_UNDEFINED,
  75         TPM_UNDEFINED,
  76         TPM_UNDEFINED,
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,          /* 5 */
  79         TPM_UNDEFINED,
  80         TPM_UNDEFINED,
  81         TPM_UNDEFINED,
  82         TPM_UNDEFINED,
  83         TPM_SHORT,              /* 10 */
  84         TPM_SHORT,
  85 };
  86
  87 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  88         TPM_UNDEFINED,          /* 0 */
  89         TPM_UNDEFINED,
  90         TPM_UNDEFINED,
  91         TPM_UNDEFINED,
  92         TPM_UNDEFINED,
  93         TPM_UNDEFINED,          /* 5 */
  94         TPM_UNDEFINED,
  95         TPM_UNDEFINED,
  96         TPM_UNDEFINED,
  97         TPM_UNDEFINED,
  98         TPM_SHORT,              /* 10 */
  99         TPM_SHORT,
 100         TPM_MEDIUM,
 101         TPM_LONG,
 102         TPM_LONG,
 103         TPM_MEDIUM,             /* 15 */
 104         TPM_SHORT,
 105         TPM_SHORT,
 106         TPM_MEDIUM,
 107         TPM_LONG,
 108         TPM_SHORT,              /* 20 */
 109         TPM_SHORT,
 110         TPM_MEDIUM,
 111         TPM_MEDIUM,
 112         TPM_MEDIUM,
 113         TPM_SHORT,              /* 25 */
 114         TPM_SHORT,
 115         TPM_MEDIUM,
 116         TPM_SHORT,
 117         TPM_SHORT,
 118         TPM_MEDIUM,             /* 30 */
 119         TPM_LONG,
 120         TPM_MEDIUM,
 121         TPM_SHORT,
 122         TPM_SHORT,
 123         TPM_SHORT,              /* 35 */
 124         TPM_MEDIUM,
 125         TPM_MEDIUM,
 126         TPM_UNDEFINED,
 127         TPM_UNDEFINED,
 128         TPM_MEDIUM,             /* 40 */
 129         TPM_LONG,
 130         TPM_MEDIUM,
 131         TPM_SHORT,
 132         TPM_SHORT,
 133         TPM_SHORT,              /* 45 */
 134         TPM_SHORT,
 135         TPM_SHORT,
 136         TPM_SHORT,
 137         TPM_LONG,
 138         TPM_MEDIUM,             /* 50 */
 139         TPM_MEDIUM,
 140         TPM_UNDEFINED,
 141         TPM_UNDEFINED,
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,          /* 55 */
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_MEDIUM,             /* 60 */
 149         TPM_MEDIUM,
 150         TPM_MEDIUM,
 151         TPM_SHORT,
 152         TPM_SHORT,
 153         TPM_MEDIUM,             /* 65 */
 154         TPM_UNDEFINED,
 155         TPM_UNDEFINED,
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_SHORT,              /* 70 */
 159         TPM_SHORT,
 160         TPM_UNDEFINED,
 161         TPM_UNDEFINED,
 162         TPM_UNDEFINED,
 163         TPM_UNDEFINED,          /* 75 */
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_LONG,               /* 80 */
 169         TPM_UNDEFINED,
 170         TPM_MEDIUM,
 171         TPM_LONG,
 172         TPM_SHORT,
 173         TPM_UNDEFINED,          /* 85 */
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_SHORT,              /* 90 */
 179         TPM_SHORT,
 180         TPM_SHORT,
 181         TPM_SHORT,
 182         TPM_SHORT,
 183         TPM_UNDEFINED,          /* 95 */
 184         TPM_UNDEFINED,
 185         TPM_UNDEFINED,
 186         TPM_UNDEFINED,
 187         TPM_UNDEFINED,
 188         TPM_MEDIUM,             /* 100 */
 189         TPM_SHORT,
 190         TPM_SHORT,
 191         TPM_UNDEFINED,
 192         TPM_UNDEFINED,
 193         TPM_UNDEFINED,          /* 105 */
 194         TPM_UNDEFINED,
 195         TPM_UNDEFINED,
 196         TPM_UNDEFINED,
 197         TPM_UNDEFINED,
 198         TPM_SHORT,              /* 110 */
 199         TPM_SHORT,
 200         TPM_SHORT,
 201         TPM_SHORT,
 202         TPM_SHORT,
 203         TPM_SHORT,              /* 115 */
 204         TPM_SHORT,
 205         TPM_SHORT,
 206         TPM_UNDEFINED,
 207         TPM_UNDEFINED,
 208         TPM_LONG,               /* 120 */
 209         TPM_LONG,
 210         TPM_MEDIUM,
 211         TPM_UNDEFINED,
 212         TPM_SHORT,
 213         TPM_SHORT,              /* 125 */
 214         TPM_SHORT,
 215         TPM_LONG,
 216         TPM_SHORT,
 217         TPM_SHORT,
 218         TPM_SHORT,              /* 130 */
 219         TPM_MEDIUM,
 220         TPM_UNDEFINED,
 221         TPM_SHORT,
 222         TPM_MEDIUM,
 223         TPM_UNDEFINED,          /* 135 */
 224         TPM_UNDEFINED,
 225         TPM_UNDEFINED,
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_SHORT,              /* 140 */
 229         TPM_SHORT,
 230         TPM_UNDEFINED,
 231         TPM_UNDEFINED,
 232         TPM_UNDEFINED,
 233         TPM_UNDEFINED,          /* 145 */
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_SHORT,              /* 150 */
 239         TPM_MEDIUM,
 240         TPM_MEDIUM,
 241         TPM_SHORT,
 242         TPM_SHORT,
 243         TPM_UNDEFINED,          /* 155 */
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_SHORT,              /* 160 */
 249         TPM_SHORT,
 250         TPM_SHORT,
 251         TPM_SHORT,
 252         TPM_UNDEFINED,
 253         TPM_UNDEFINED,          /* 165 */
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,
 256         TPM_UNDEFINED,
 257         TPM_UNDEFINED,
 258         TPM_LONG,               /* 170 */
 259         TPM_UNDEFINED,
 260         TPM_UNDEFINED,
 261         TPM_UNDEFINED,
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,          /* 175 */
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_MEDIUM,             /* 180 */
 269         TPM_SHORT,
 270         TPM_MEDIUM,
 271         TPM_MEDIUM,
 272         TPM_MEDIUM,
 273         TPM_MEDIUM,             /* 185 */
 274         TPM_SHORT,
 275         TPM_UNDEFINED,
 276         TPM_UNDEFINED,
 277         TPM_UNDEFINED,
 278         TPM_UNDEFINED,          /* 190 */
 279         TPM_UNDEFINED,
 280         TPM_UNDEFINED,
 281         TPM_UNDEFINED,
 282         TPM_UNDEFINED,
 283         TPM_UNDEFINED,          /* 195 */
 284         TPM_UNDEFINED,
 285         TPM_UNDEFINED,
 286         TPM_UNDEFINED,
 287         TPM_UNDEFINED,
 288         TPM_SHORT,              /* 200 */
 289         TPM_UNDEFINED,
 290         TPM_UNDEFINED,
 291         TPM_UNDEFINED,
 292         TPM_SHORT,
 293         TPM_SHORT,              /* 205 */
 294         TPM_SHORT,
 295         TPM_SHORT,
 296         TPM_SHORT,
 297         TPM_SHORT,
 298         TPM_MEDIUM,             /* 210 */
 299         TPM_UNDEFINED,
 300         TPM_MEDIUM,
 301         TPM_MEDIUM,
 302         TPM_MEDIUM,
 303         TPM_UNDEFINED,          /* 215 */
 304         TPM_MEDIUM,
 305         TPM_UNDEFINED,
 306         TPM_UNDEFINED,
 307         TPM_SHORT,
 308         TPM_SHORT,              /* 220 */
 309         TPM_SHORT,
 310         TPM_SHORT,
 311         TPM_SHORT,
 312         TPM_SHORT,
 313         TPM_UNDEFINED,          /* 225 */
 314         TPM_UNDEFINED,
 315         TPM_UNDEFINED,
 316         TPM_UNDEFINED,
 317         TPM_UNDEFINED,
 318         TPM_SHORT,              /* 230 */
 319         TPM_LONG,
 320         TPM_MEDIUM,
 321         TPM_UNDEFINED,
 322         TPM_UNDEFINED,
 323         TPM_UNDEFINED,          /* 235 */
 324         TPM_UNDEFINED,
 325         TPM_UNDEFINED,
 326         TPM_UNDEFINED,
 327         TPM_UNDEFINED,
 328         TPM_SHORT,              /* 240 */
 329         TPM_UNDEFINED,
 330         TPM_MEDIUM,
 331 };
 332
 333 static void user_reader_timeout(unsigned long ptr)
 334 {
 335         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 336
 337         schedule_work(&chip->work);
 338 }
 339
 340 static void timeout_work(struct work_struct *work)
 341 {
 342         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 343
 344         mutex_lock(&chip->buffer_mutex);
 345         atomic_set(&chip->data_pending, 0);
 346         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 347         mutex_unlock(&chip->buffer_mutex);
 348 }
 349
 350 /*
 351  * Returns max number of jiffies to wait
 352  */
 353 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 354                                            u32 ordinal)
 355 {
 356         int duration_idx = TPM_UNDEFINED;
 357         int duration = 0;
 358
 359         if (ordinal < TPM_MAX_ORDINAL)
 360                 duration_idx = tpm_ordinal_duration[ordinal];
 361         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 362                  TPM_MAX_PROTECTED_ORDINAL)
 363                 duration_idx =
 364                     tpm_protected_ordinal_duration[ordinal &
 365                                                    TPM_PROTECTED_ORDINAL_MASK];
 366
 367         if (duration_idx != TPM_UNDEFINED) {
 368                 duration = chip->vendor.duration[duration_idx];
 369                 /* if duration is 0, it's because chip->vendor.duration wasn't */
 370                 /* filled yet, so we set the lowest timeout just to give enough */
 371                 /* time for tpm_get_timeouts() to succeed */
 372                 return (duration <= 0 ? HZ : duration);
 373         } else
 374                 return 2 * 60 * HZ;
 375 }
 376 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 377
 378 /*
 379  * Internal kernel interface to transmit TPM commands
 380  */
 381 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 382                             size_t bufsiz)
 383 {
 384         ssize_t rc;
 385         u32 count, ordinal;
 386         unsigned long stop;
 387
 388         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 389         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 390         if (count == 0)
 391                 return -ENODATA;
 392         if (count > bufsiz) {
 393                 dev_err(chip->dev,
 394                         "invalid count value %x %zx \n", count, bufsiz);
 395                 return -E2BIG;
 396         }
 397
 398         mutex_lock(&chip->tpm_mutex);
 399
 400         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 401                 dev_err(chip->dev,
 402                         "tpm_transmit: tpm_send: error %zd\n", rc);
 403                 goto out;
 404         }
 405
 406         if (chip->vendor.irq)
 407                 goto out_recv;
 408
 409         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 410         do {
 411                 u8 status = chip->vendor.status(chip);
 412                 if ((status & chip->vendor.req_complete_mask) ==
 413                     chip->vendor.req_complete_val)
 414                         goto out_recv;
 415
 416                 if ((status == chip->vendor.req_canceled)) {
 417                         dev_err(chip->dev, "Operation Canceled\n");
 418                         rc = -ECANCELED;
 419                         goto out;
 420                 }
 421
 422                 msleep(TPM_TIMEOUT);    /* CHECK */
 423                 rmb();
 424         } while (time_before(jiffies, stop));
 425
 426         chip->vendor.cancel(chip);
 427         dev_err(chip->dev, "Operation Timed out\n");
 428         rc = -ETIME;
 429         goto out;
 430
 431 out_recv:
 432         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 433         if (rc < 0)
 434                 dev_err(chip->dev,
 435                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 436 out:
 437         mutex_unlock(&chip->tpm_mutex);
 438         return rc;
 439 }
 440
 441 #define TPM_DIGEST_SIZE 20
 442 #define TPM_ERROR_SIZE 10
 443 #define TPM_RET_CODE_IDX 6
 444
 445 enum tpm_capabilities {
 446         TPM_CAP_FLAG = cpu_to_be32(4),
 447         TPM_CAP_PROP = cpu_to_be32(5),
 448         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 449         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 450 };
 451
 452 enum tpm_sub_capabilities {
 453         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 454         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 455         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 456         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 457         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 458         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 459         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 460
 461 };
 462
 463 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 464                             int len, const char *desc)
 465 {
 466         int err;
 467
 468         len = tpm_transmit(chip,(u8 *) cmd, len);
 469         if (len <  0)
 470                 return len;
 471         if (len == TPM_ERROR_SIZE) {
 472                 err = be32_to_cpu(cmd->header.out.return_code);
 473                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 474                 return err;
 475         }
 476         return 0;
 477 }
 478
 479 #define TPM_INTERNAL_RESULT_SIZE 200
 480 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 481 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 482
 483 static const struct tpm_input_header tpm_getcap_header = {
 484         .tag = TPM_TAG_RQU_COMMAND,
 485         .length = cpu_to_be32(22),
 486         .ordinal = TPM_ORD_GET_CAP
 487 };
 488
 489 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 490                    const char *desc)
 491 {
 492         struct tpm_cmd_t tpm_cmd;
 493         int rc;
 494         struct tpm_chip *chip = dev_get_drvdata(dev);
 495
 496         tpm_cmd.header.in = tpm_getcap_header;
 497         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 498                 tpm_cmd.params.getcap_in.cap = subcap_id;
 499                 /*subcap field not necessary */
 500                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 501                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 502         } else {
 503                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 504                     subcap_id == TPM_CAP_FLAG_VOL)
 505                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 506                 else
 507                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 508                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 509                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 510         }
 511         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 512         if (!rc)
 513                 *cap = tpm_cmd.params.getcap_out.cap;
 514         return rc;
 515 }
 516
 517 void tpm_gen_interrupt(struct tpm_chip *chip)
 518 {
 519         struct  tpm_cmd_t tpm_cmd;
 520         ssize_t rc;
 521
 522         tpm_cmd.header.in = tpm_getcap_header;
 523         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 524         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 525         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 526
 527         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 528                         "attempting to determine the timeouts");
 529 }
 530 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 531
 532 void tpm_get_timeouts(struct tpm_chip *chip)
 533 {
 534         struct tpm_cmd_t tpm_cmd;
 535         struct timeout_t *timeout_cap;
 536         struct duration_t *duration_cap;
 537         ssize_t rc;
 538         u32 timeout;
 539
 540         tpm_cmd.header.in = tpm_getcap_header;
 541         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 542         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 543         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 544
 545         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 546                         "attempting to determine the timeouts");
 547         if (rc)
 548                 goto duration;
 549
 550         if (be32_to_cpu(tpm_cmd.header.out.length)
 551             != 4 * sizeof(u32))
 552                 goto duration;
 553
 554         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 555         /* Don't overwrite default if value is 0 */
 556         timeout = be32_to_cpu(timeout_cap->a);
 557         if (timeout)
 558                 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
 559         timeout = be32_to_cpu(timeout_cap->b);
 560         if (timeout)
 561                 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
 562         timeout = be32_to_cpu(timeout_cap->c);
 563         if (timeout)
 564                 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
 565         timeout = be32_to_cpu(timeout_cap->d);
 566         if (timeout)
 567                 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
 568
 569 duration:
 570         tpm_cmd.header.in = tpm_getcap_header;
 571         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 572         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 573         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 574
 575         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 576                         "attempting to determine the durations");
 577         if (rc)
 578                 return;
 579
 580         if (be32_to_cpu(tpm_cmd.header.out.return_code)
 581             != 3 * sizeof(u32))
 582                 return;
 583         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 584         chip->vendor.duration[TPM_SHORT] =
 585             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 586         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 587          * value wrong and apparently reports msecs rather than usecs. So we
 588          * fix up the resulting too-small TPM_SHORT value to make things work.
 589          */
 590         if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
 591                 chip->vendor.duration[TPM_SHORT] = HZ;
 592
 593         chip->vendor.duration[TPM_MEDIUM] =
 594             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 595         chip->vendor.duration[TPM_LONG] =
 596             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 597 }
 598 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 599
 600 void tpm_continue_selftest(struct tpm_chip *chip)
 601 {
 602         u8 data[] = {
 603                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 604                 0, 0, 0, 10,            /* length */
 605                 0, 0, 0, 83,            /* TPM_ORD_GetCapability */
 606         };
 607
 608         tpm_transmit(chip, data, sizeof(data));
 609 }
 610 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 611
 612 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 613                         char *buf)
 614 {
 615         cap_t cap;
 616         ssize_t rc;
 617
 618         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 619                          "attempting to determine the permanent enabled state");
 620         if (rc)
 621                 return 0;
 622
 623         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 624         return rc;
 625 }
 626 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 627
 628 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 629                         char *buf)
 630 {
 631         cap_t cap;
 632         ssize_t rc;
 633
 634         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 635                          "attempting to determine the permanent active state");
 636         if (rc)
 637                 return 0;
 638
 639         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 640         return rc;
 641 }
 642 EXPORT_SYMBOL_GPL(tpm_show_active);
 643
 644 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 645                         char *buf)
 646 {
 647         cap_t cap;
 648         ssize_t rc;
 649
 650         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 651                          "attempting to determine the owner state");
 652         if (rc)
 653                 return 0;
 654
 655         rc = sprintf(buf, "%d\n", cap.owned);
 656         return rc;
 657 }
 658 EXPORT_SYMBOL_GPL(tpm_show_owned);
 659
 660 ssize_t tpm_show_temp_deactivated(struct device * dev,
 661                                 struct device_attribute * attr, char *buf)
 662 {
 663         cap_t cap;
 664         ssize_t rc;
 665
 666         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 667                          "attempting to determine the temporary state");
 668         if (rc)
 669                 return 0;
 670
 671         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 672         return rc;
 673 }
 674 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 675
 676 /*
 677  * tpm_chip_find_get - return tpm_chip for given chip number
 678  */
 679 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 680 {
 681         struct tpm_chip *pos, *chip = NULL;
 682
 683         rcu_read_lock();
 684         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 685                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 686                         continue;
 687
 688                 if (try_module_get(pos->dev->driver->owner)) {
 689                         chip = pos;
 690                         break;
 691                 }
 692         }
 693         rcu_read_unlock();
 694         return chip;
 695 }
 696
 697 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 698 #define READ_PCR_RESULT_SIZE 30
 699 static struct tpm_input_header pcrread_header = {
 700         .tag = TPM_TAG_RQU_COMMAND,
 701         .length = cpu_to_be32(14),
 702         .ordinal = TPM_ORDINAL_PCRREAD
 703 };
 704
 705 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 706 {
 707         int rc;
 708         struct tpm_cmd_t cmd;
 709
 710         cmd.header.in = pcrread_header;
 711         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 712         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 713                           "attempting to read a pcr value");
 714
 715         if (rc == 0)
 716                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 717                        TPM_DIGEST_SIZE);
 718         return rc;
 719 }
 720
 721 /**
 722  * tpm_pcr_read - read a pcr value
 723  * @chip_num:   tpm idx # or ANY
 724  * @pcr_idx:    pcr idx to retrieve
 725  * @res_buf:    TPM_PCR value
 726  *              size of res_buf is 20 bytes (or NULL if you don't care)
 727  *
 728  * The TPM driver should be built-in, but for whatever reason it
 729  * isn't, protect against the chip disappearing, by incrementing
 730  * the module usage count.
 731  */
 732 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 733 {
 734         struct tpm_chip *chip;
 735         int rc;
 736
 737         chip = tpm_chip_find_get(chip_num);
 738         if (chip == NULL)
 739                 return -ENODEV;
 740         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 741         tpm_chip_put(chip);
 742         return rc;
 743 }
 744 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 745
 746 /**
 747  * tpm_pcr_extend - extend pcr value with hash
 748  * @chip_num:   tpm idx # or AN&
 749  * @pcr_idx:    pcr idx to extend
 750  * @hash:       hash value used to extend pcr value
 751  *
 752  * The TPM driver should be built-in, but for whatever reason it
 753  * isn't, protect against the chip disappearing, by incrementing
 754  * the module usage count.
 755  */
 756 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 757 #define EXTEND_PCR_RESULT_SIZE 34
 758 static struct tpm_input_header pcrextend_header = {
 759         .tag = TPM_TAG_RQU_COMMAND,
 760         .length = cpu_to_be32(34),
 761         .ordinal = TPM_ORD_PCR_EXTEND
 762 };
 763
 764 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 765 {
 766         struct tpm_cmd_t cmd;
 767         int rc;
 768         struct tpm_chip *chip;
 769
 770         chip = tpm_chip_find_get(chip_num);
 771         if (chip == NULL)
 772                 return -ENODEV;
 773
 774         cmd.header.in = pcrextend_header;
 775         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 776         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 777         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 778                           "attempting extend a PCR value");
 779
 780         tpm_chip_put(chip);
 781         return rc;
 782 }
 783 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 784
 785 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 786 {
 787         struct tpm_chip *chip;
 788         int rc;
 789
 790         chip = tpm_chip_find_get(chip_num);
 791         if (chip == NULL)
 792                 return -ENODEV;
 793
 794         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 795
 796         tpm_chip_put(chip);
 797         return rc;
 798 }
 799 EXPORT_SYMBOL_GPL(tpm_send);
 800
 801 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 802                       char *buf)
 803 {
 804         cap_t cap;
 805         u8 digest[TPM_DIGEST_SIZE];
 806         ssize_t rc;
 807         int i, j, num_pcrs;
 808         char *str = buf;
 809         struct tpm_chip *chip = dev_get_drvdata(dev);
 810
 811         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 812                         "attempting to determine the number of PCRS");
 813         if (rc)
 814                 return 0;
 815
 816         num_pcrs = be32_to_cpu(cap.num_pcrs);
 817         for (i = 0; i < num_pcrs; i++) {
 818                 rc = __tpm_pcr_read(chip, i, digest);
 819                 if (rc)
 820                         break;
 821                 str += sprintf(str, "PCR-%02d: ", i);
 822                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 823                         str += sprintf(str, "%02X ", digest[j]);
 824                 str += sprintf(str, "\n");
 825         }
 826         return str - buf;
 827 }
 828 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 829
 830 #define  READ_PUBEK_RESULT_SIZE 314
 831 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 832 struct tpm_input_header tpm_readpubek_header = {
 833         .tag = TPM_TAG_RQU_COMMAND,
 834         .length = cpu_to_be32(30),
 835         .ordinal = TPM_ORD_READPUBEK
 836 };
 837
 838 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 839                        char *buf)
 840 {
 841         u8 *data;
 842         struct tpm_cmd_t tpm_cmd;
 843         ssize_t err;
 844         int i, rc;
 845         char *str = buf;
 846
 847         struct tpm_chip *chip = dev_get_drvdata(dev);
 848
 849         tpm_cmd.header.in = tpm_readpubek_header;
 850         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 851                         "attempting to read the PUBEK");
 852         if (err)
 853                 goto out;
 854
 855         /*
 856            ignore header 10 bytes
 857            algorithm 32 bits (1 == RSA )
 858            encscheme 16 bits
 859            sigscheme 16 bits
 860            parameters (RSA 12->bytes: keybit, #primes, expbit)
 861            keylenbytes 32 bits
 862            256 byte modulus
 863            ignore checksum 20 bytes
 864          */
 865         data = tpm_cmd.params.readpubek_out_buffer;
 866         str +=
 867             sprintf(str,
 868                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
 869                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
 870                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
 871                     "Modulus length: %d\nModulus: \n",
 872                     data[10], data[11], data[12], data[13], data[14],
 873                     data[15], data[16], data[17], data[22], data[23],
 874                     data[24], data[25], data[26], data[27], data[28],
 875                     data[29], data[30], data[31], data[32], data[33],
 876                     be32_to_cpu(*((__be32 *) (data + 34))));
 877
 878         for (i = 0; i < 256; i++) {
 879                 str += sprintf(str, "%02X ", data[i + 38]);
 880                 if ((i + 1) % 16 == 0)
 881                         str += sprintf(str, "\n");
 882         }
 883 out:
 884         rc = str - buf;
 885         return rc;
 886 }
 887 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 888
 889
 890 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 891                       char *buf)
 892 {
 893         cap_t cap;
 894         ssize_t rc;
 895         char *str = buf;
 896
 897         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 898                         "attempting to determine the manufacturer");
 899         if (rc)
 900                 return 0;
 901         str += sprintf(str, "Manufacturer: 0x%x\n",
 902                        be32_to_cpu(cap.manufacturer_id));
 903
 904         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
 905                         "attempting to determine the 1.1 version");
 906         if (rc)
 907                 return 0;
 908         str += sprintf(str,
 909                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 910                        cap.tpm_version.Major, cap.tpm_version.Minor,
 911                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
 912         return str - buf;
 913 }
 914 EXPORT_SYMBOL_GPL(tpm_show_caps);
 915
 916 ssize_t tpm_show_caps_1_2(struct device * dev,
 917                           struct device_attribute * attr, char *buf)
 918 {
 919         cap_t cap;
 920         ssize_t rc;
 921         char *str = buf;
 922
 923         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 924                         "attempting to determine the manufacturer");
 925         if (rc)
 926                 return 0;
 927         str += sprintf(str, "Manufacturer: 0x%x\n",
 928                        be32_to_cpu(cap.manufacturer_id));
 929         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
 930                          "attempting to determine the 1.2 version");
 931         if (rc)
 932                 return 0;
 933         str += sprintf(str,
 934                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 935                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
 936                        cap.tpm_version_1_2.revMajor,
 937                        cap.tpm_version_1_2.revMinor);
 938         return str - buf;
 939 }
 940 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 941
 942 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 943                         const char *buf, size_t count)
 944 {
 945         struct tpm_chip *chip = dev_get_drvdata(dev);
 946         if (chip == NULL)
 947                 return 0;
 948
 949         chip->vendor.cancel(chip);
 950         return count;
 951 }
 952 EXPORT_SYMBOL_GPL(tpm_store_cancel);
 953
 954 /*
 955  * Device file system interface to the TPM
 956  *
 957  * It's assured that the chip will be opened just once,
 958  * by the check of is_open variable, which is protected
 959  * by driver_lock.
 960  */
 961 int tpm_open(struct inode *inode, struct file *file)
 962 {
 963         int minor = iminor(inode);
 964         struct tpm_chip *chip = NULL, *pos;
 965
 966         rcu_read_lock();
 967         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 968                 if (pos->vendor.miscdev.minor == minor) {
 969                         chip = pos;
 970                         get_device(chip->dev);
 971                         break;
 972                 }
 973         }
 974         rcu_read_unlock();
 975
 976         if (!chip)
 977                 return -ENODEV;
 978
 979         if (test_and_set_bit(0, &chip->is_open)) {
 980                 dev_dbg(chip->dev, "Another process owns this TPM\n");
 981                 put_device(chip->dev);
 982                 return -EBUSY;
 983         }
 984
 985         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 986         if (chip->data_buffer == NULL) {
 987                 clear_bit(0, &chip->is_open);
 988                 put_device(chip->dev);
 989                 return -ENOMEM;
 990         }
 991
 992         atomic_set(&chip->data_pending, 0);
 993
 994         file->private_data = chip;
 995         return 0;
 996 }
 997 EXPORT_SYMBOL_GPL(tpm_open);
 998
 999 /*
1000  * Called on file close
1001  */
1002 int tpm_release(struct inode *inode, struct file *file)
1003 {
1004         struct tpm_chip *chip = file->private_data;
1005
1006         del_singleshot_timer_sync(&chip->user_read_timer);
1007         flush_work_sync(&chip->work);
1008         file->private_data = NULL;
1009         atomic_set(&chip->data_pending, 0);
1010         kfree(chip->data_buffer);
1011         clear_bit(0, &chip->is_open);
1012         put_device(chip->dev);
1013         return 0;
1014 }
1015 EXPORT_SYMBOL_GPL(tpm_release);
1016
1017 ssize_t tpm_write(struct file *file, const char __user *buf,
1018                   size_t size, loff_t *off)
1019 {
1020         struct tpm_chip *chip = file->private_data;
1021         size_t in_size = size, out_size;
1022
1023         /* cannot perform a write until the read has cleared
1024            either via tpm_read or a user_read_timer timeout */
1025         while (atomic_read(&chip->data_pending) != 0)
1026                 msleep(TPM_TIMEOUT);
1027
1028         mutex_lock(&chip->buffer_mutex);
1029
1030         if (in_size > TPM_BUFSIZE)
1031                 in_size = TPM_BUFSIZE;
1032
1033         if (copy_from_user
1034             (chip->data_buffer, (void __user *) buf, in_size)) {
1035                 mutex_unlock(&chip->buffer_mutex);
1036                 return -EFAULT;
1037         }
1038
1039         /* atomic tpm command send and result receive */
1040         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1041
1042         atomic_set(&chip->data_pending, out_size);
1043         mutex_unlock(&chip->buffer_mutex);
1044
1045         /* Set a timeout by which the reader must come claim the result */
1046         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1047
1048         return in_size;
1049 }
1050 EXPORT_SYMBOL_GPL(tpm_write);
1051
1052 ssize_t tpm_read(struct file *file, char __user *buf,
1053                  size_t size, loff_t *off)
1054 {
1055         struct tpm_chip *chip = file->private_data;
1056         ssize_t ret_size;
1057
1058         del_singleshot_timer_sync(&chip->user_read_timer);
1059         flush_work_sync(&chip->work);
1060         ret_size = atomic_read(&chip->data_pending);
1061         atomic_set(&chip->data_pending, 0);
1062         if (ret_size > 0) {     /* relay data */
1063                 if (size < ret_size)
1064                         ret_size = size;
1065
1066                 mutex_lock(&chip->buffer_mutex);
1067                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1068                         ret_size = -EFAULT;
1069                 mutex_unlock(&chip->buffer_mutex);
1070         }
1071
1072         return ret_size;
1073 }
1074 EXPORT_SYMBOL_GPL(tpm_read);
1075
1076 void tpm_remove_hardware(struct device *dev)
1077 {
1078         struct tpm_chip *chip = dev_get_drvdata(dev);
1079
1080         if (chip == NULL) {
1081                 dev_err(dev, "No device data found\n");
1082                 return;
1083         }
1084
1085         spin_lock(&driver_lock);
1086         list_del_rcu(&chip->list);
1087         spin_unlock(&driver_lock);
1088         synchronize_rcu();
1089
1090         misc_deregister(&chip->vendor.miscdev);
1091         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1092         tpm_bios_log_teardown(chip->bios_dir);
1093
1094         /* write it this way to be explicit (chip->dev == dev) */
1095         put_device(chip->dev);
1096 }
1097 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1098
1099 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1100 #define SAVESTATE_RESULT_SIZE 10
1101
1102 static struct tpm_input_header savestate_header = {
1103         .tag = TPM_TAG_RQU_COMMAND,
1104         .length = cpu_to_be32(10),
1105         .ordinal = TPM_ORD_SAVESTATE
1106 };
1107
1108 /*
1109  * We are about to suspend. Save the TPM state
1110  * so that it can be restored.
1111  */
1112 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1113 {
1114         struct tpm_chip *chip = dev_get_drvdata(dev);
1115         struct tpm_cmd_t cmd;
1116         int rc;
1117
1118         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1119
1120         if (chip == NULL)
1121                 return -ENODEV;
1122
1123         /* for buggy tpm, flush pcrs with extend to selected dummy */
1124         if (tpm_suspend_pcr) {
1125                 cmd.header.in = pcrextend_header;
1126                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1127                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1128                        TPM_DIGEST_SIZE);
1129                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1130                                   "extending dummy pcr before suspend");
1131         }
1132
1133         /* now do the actual savestate */
1134         cmd.header.in = savestate_header;
1135         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1136                           "sending savestate before suspend");
1137         return rc;
1138 }
1139 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1140
1141 /*
1142  * Resume from a power safe. The BIOS already restored
1143  * the TPM state.
1144  */
1145 int tpm_pm_resume(struct device *dev)
1146 {
1147         struct tpm_chip *chip = dev_get_drvdata(dev);
1148
1149         if (chip == NULL)
1150                 return -ENODEV;
1151
1152         return 0;
1153 }
1154 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1155
1156 /* In case vendor provided release function, call it too.*/
1157
1158 void tpm_dev_vendor_release(struct tpm_chip *chip)
1159 {
1160         if (chip->vendor.release)
1161                 chip->vendor.release(chip->dev);
1162
1163         clear_bit(chip->dev_num, dev_mask);
1164         kfree(chip->vendor.miscdev.name);
1165 }
1166 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1167
1168
1169 /*
1170  * Once all references to platform device are down to 0,
1171  * release all allocated structures.
1172  */
1173 void tpm_dev_release(struct device *dev)
1174 {
1175         struct tpm_chip *chip = dev_get_drvdata(dev);
1176
1177         tpm_dev_vendor_release(chip);
1178
1179         chip->release(dev);
1180         kfree(chip);
1181 }
1182 EXPORT_SYMBOL_GPL(tpm_dev_release);
1183
1184 /*
1185  * Called from tpm_<specific>.c probe function only for devices
1186  * the driver has determined it should claim.  Prior to calling
1187  * this function the specific probe function has called pci_enable_device
1188  * upon errant exit from this function specific probe function should call
1189  * pci_disable_device
1190  */
1191 struct tpm_chip *tpm_register_hardware(struct device *dev,
1192                                         const struct tpm_vendor_specific *entry)
1193 {
1194 #define DEVNAME_SIZE 7
1195
1196         char *devname;
1197         struct tpm_chip *chip;
1198
1199         /* Driver specific per-device data */
1200         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1201         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1202
1203         if (chip == NULL || devname == NULL)
1204                 goto out_free;
1205
1206         mutex_init(&chip->buffer_mutex);
1207         mutex_init(&chip->tpm_mutex);
1208         INIT_LIST_HEAD(&chip->list);
1209
1210         INIT_WORK(&chip->work, timeout_work);
1211
1212         setup_timer(&chip->user_read_timer, user_reader_timeout,
1213                         (unsigned long)chip);
1214
1215         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1216
1217         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1218
1219         if (chip->dev_num >= TPM_NUM_DEVICES) {
1220                 dev_err(dev, "No available tpm device numbers\n");
1221                 goto out_free;
1222         } else if (chip->dev_num == 0)
1223                 chip->vendor.miscdev.minor = TPM_MINOR;
1224         else
1225                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1226
1227         set_bit(chip->dev_num, dev_mask);
1228
1229         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1230         chip->vendor.miscdev.name = devname;
1231
1232         chip->vendor.miscdev.parent = dev;
1233         chip->dev = get_device(dev);
1234         chip->release = dev->release;
1235         dev->release = tpm_dev_release;
1236         dev_set_drvdata(dev, chip);
1237
1238         if (misc_register(&chip->vendor.miscdev)) {
1239                 dev_err(chip->dev,
1240                         "unable to misc_register %s, minor %d\n",
1241                         chip->vendor.miscdev.name,
1242                         chip->vendor.miscdev.minor);
1243                 put_device(chip->dev);
1244                 return NULL;
1245         }
1246
1247         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1248                 misc_deregister(&chip->vendor.miscdev);
1249                 put_device(chip->dev);
1250
1251                 return NULL;
1252         }
1253
1254         chip->bios_dir = tpm_bios_log_setup(devname);
1255
1256         /* Make chip available */
1257         spin_lock(&driver_lock);
1258         list_add_rcu(&chip->list, &tpm_chip_list);
1259         spin_unlock(&driver_lock);
1260
1261         return chip;
1262
1263 out_free:
1264         kfree(chip);
1265         kfree(devname);
1266         return NULL;
1267 }
1268 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1269
1270 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1271 MODULE_DESCRIPTION("TPM Driver");
1272 MODULE_VERSION("2.0");
1273 MODULE_LICENSE("GPL");