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 <= 0)
 370                 return 2 * 60 * HZ;
 371         else
 372                 return duration;
 373 }
 374 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 375
 376 /*
 377  * Internal kernel interface to transmit TPM commands
 378  */
 379 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 380                             size_t bufsiz)
 381 {
 382         ssize_t rc;
 383         u32 count, ordinal;
 384         unsigned long stop;
 385
 386         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 387         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 388         if (count == 0)
 389                 return -ENODATA;
 390         if (count > bufsiz) {
 391                 dev_err(chip->dev,
 392                         "invalid count value %x %zx \n", count, bufsiz);
 393                 return -E2BIG;
 394         }
 395
 396         mutex_lock(&chip->tpm_mutex);
 397
 398         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 399                 dev_err(chip->dev,
 400                         "tpm_transmit: tpm_send: error %zd\n", rc);
 401                 goto out;
 402         }
 403
 404         if (chip->vendor.irq)
 405                 goto out_recv;
 406
 407         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 408         do {
 409                 u8 status = chip->vendor.status(chip);
 410                 if ((status & chip->vendor.req_complete_mask) ==
 411                     chip->vendor.req_complete_val)
 412                         goto out_recv;
 413
 414                 if ((status == chip->vendor.req_canceled)) {
 415                         dev_err(chip->dev, "Operation Canceled\n");
 416                         rc = -ECANCELED;
 417                         goto out;
 418                 }
 419
 420                 msleep(TPM_TIMEOUT);    /* CHECK */
 421                 rmb();
 422         } while (time_before(jiffies, stop));
 423
 424         chip->vendor.cancel(chip);
 425         dev_err(chip->dev, "Operation Timed out\n");
 426         rc = -ETIME;
 427         goto out;
 428
 429 out_recv:
 430         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 431         if (rc < 0)
 432                 dev_err(chip->dev,
 433                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 434 out:
 435         mutex_unlock(&chip->tpm_mutex);
 436         return rc;
 437 }
 438
 439 #define TPM_DIGEST_SIZE 20
 440 #define TPM_ERROR_SIZE 10
 441 #define TPM_RET_CODE_IDX 6
 442
 443 enum tpm_capabilities {
 444         TPM_CAP_FLAG = cpu_to_be32(4),
 445         TPM_CAP_PROP = cpu_to_be32(5),
 446         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 447         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 448 };
 449
 450 enum tpm_sub_capabilities {
 451         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 452         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 453         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 454         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 455         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 456         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 457         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 458
 459 };
 460
 461 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 462                             int len, const char *desc)
 463 {
 464         int err;
 465
 466         len = tpm_transmit(chip,(u8 *) cmd, len);
 467         if (len <  0)
 468                 return len;
 469         if (len == TPM_ERROR_SIZE) {
 470                 err = be32_to_cpu(cmd->header.out.return_code);
 471                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 472                 return err;
 473         }
 474         return 0;
 475 }
 476
 477 #define TPM_INTERNAL_RESULT_SIZE 200
 478 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 479 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 480
 481 static const struct tpm_input_header tpm_getcap_header = {
 482         .tag = TPM_TAG_RQU_COMMAND,
 483         .length = cpu_to_be32(22),
 484         .ordinal = TPM_ORD_GET_CAP
 485 };
 486
 487 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 488                    const char *desc)
 489 {
 490         struct tpm_cmd_t tpm_cmd;
 491         int rc;
 492         struct tpm_chip *chip = dev_get_drvdata(dev);
 493
 494         tpm_cmd.header.in = tpm_getcap_header;
 495         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 496                 tpm_cmd.params.getcap_in.cap = subcap_id;
 497                 /*subcap field not necessary */
 498                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 499                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 500         } else {
 501                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 502                     subcap_id == TPM_CAP_FLAG_VOL)
 503                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 504                 else
 505                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 506                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 507                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 508         }
 509         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 510         if (!rc)
 511                 *cap = tpm_cmd.params.getcap_out.cap;
 512         return rc;
 513 }
 514
 515 void tpm_gen_interrupt(struct tpm_chip *chip)
 516 {
 517         struct  tpm_cmd_t tpm_cmd;
 518         ssize_t rc;
 519
 520         tpm_cmd.header.in = tpm_getcap_header;
 521         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 522         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 523         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 524
 525         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 526                         "attempting to determine the timeouts");
 527 }
 528 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 529
 530 int tpm_get_timeouts(struct tpm_chip *chip)
 531 {
 532         struct tpm_cmd_t tpm_cmd;
 533         struct timeout_t *timeout_cap;
 534         struct duration_t *duration_cap;
 535         ssize_t rc;
 536         u32 timeout;
 537         unsigned int scale = 1;
 538
 539         tpm_cmd.header.in = tpm_getcap_header;
 540         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 541         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 542         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 543
 544         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 545                         "attempting to determine the timeouts");
 546         if (rc)
 547                 goto duration;
 548
 549         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 550             be32_to_cpu(tpm_cmd.header.out.length)
 551             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 552                 return -EINVAL;
 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 && timeout < 1000) {
 558                 /* timeouts in msec rather usec */
 559                 scale = 1000;
 560                 chip->vendor.timeout_adjusted = true;
 561         }
 562         if (timeout)
 563                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 564         timeout = be32_to_cpu(timeout_cap->b);
 565         if (timeout)
 566                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 567         timeout = be32_to_cpu(timeout_cap->c);
 568         if (timeout)
 569                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 570         timeout = be32_to_cpu(timeout_cap->d);
 571         if (timeout)
 572                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 573
 574 duration:
 575         tpm_cmd.header.in = tpm_getcap_header;
 576         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 577         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 578         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 579
 580         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 581                         "attempting to determine the durations");
 582         if (rc)
 583                 return rc;
 584
 585         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 586             be32_to_cpu(tpm_cmd.header.out.length)
 587             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 588                 return -EINVAL;
 589
 590         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 591         chip->vendor.duration[TPM_SHORT] =
 592             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 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         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 599          * value wrong and apparently reports msecs rather than usecs. So we
 600          * fix up the resulting too-small TPM_SHORT value to make things work.
 601          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 602          */
 603         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 604                 chip->vendor.duration[TPM_SHORT] = HZ;
 605                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 606                 chip->vendor.duration[TPM_LONG] *= 1000;
 607                 chip->vendor.duration_adjusted = true;
 608                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 609         }
 610         return 0;
 611 }
 612 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 613
 614 #define TPM_ORD_CONTINUE_SELFTEST 83
 615 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 616
 617 static struct tpm_input_header continue_selftest_header = {
 618         .tag = TPM_TAG_RQU_COMMAND,
 619         .length = cpu_to_be32(10),
 620         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 621 };
 622
 623 /**
 624  * tpm_continue_selftest -- run TPM's selftest
 625  * @chip: TPM chip to use
 626  *
 627  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 628  * a TPM error code.
 629  */
 630 int tpm_continue_selftest(struct tpm_chip *chip)
 631 {
 632         int rc;
 633         struct tpm_cmd_t cmd;
 634
 635         cmd.header.in = continue_selftest_header;
 636         rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
 637                           "continue selftest");
 638         return rc;
 639 }
 640 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 641
 642 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 643                         char *buf)
 644 {
 645         cap_t cap;
 646         ssize_t rc;
 647
 648         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 649                          "attempting to determine the permanent enabled state");
 650         if (rc)
 651                 return 0;
 652
 653         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 654         return rc;
 655 }
 656 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 657
 658 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 659                         char *buf)
 660 {
 661         cap_t cap;
 662         ssize_t rc;
 663
 664         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 665                          "attempting to determine the permanent active state");
 666         if (rc)
 667                 return 0;
 668
 669         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 670         return rc;
 671 }
 672 EXPORT_SYMBOL_GPL(tpm_show_active);
 673
 674 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 675                         char *buf)
 676 {
 677         cap_t cap;
 678         ssize_t rc;
 679
 680         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 681                          "attempting to determine the owner state");
 682         if (rc)
 683                 return 0;
 684
 685         rc = sprintf(buf, "%d\n", cap.owned);
 686         return rc;
 687 }
 688 EXPORT_SYMBOL_GPL(tpm_show_owned);
 689
 690 ssize_t tpm_show_temp_deactivated(struct device * dev,
 691                                 struct device_attribute * attr, char *buf)
 692 {
 693         cap_t cap;
 694         ssize_t rc;
 695
 696         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 697                          "attempting to determine the temporary state");
 698         if (rc)
 699                 return 0;
 700
 701         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 702         return rc;
 703 }
 704 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 705
 706 /*
 707  * tpm_chip_find_get - return tpm_chip for given chip number
 708  */
 709 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 710 {
 711         struct tpm_chip *pos, *chip = NULL;
 712
 713         rcu_read_lock();
 714         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 715                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 716                         continue;
 717
 718                 if (try_module_get(pos->dev->driver->owner)) {
 719                         chip = pos;
 720                         break;
 721                 }
 722         }
 723         rcu_read_unlock();
 724         return chip;
 725 }
 726
 727 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 728 #define READ_PCR_RESULT_SIZE 30
 729 static struct tpm_input_header pcrread_header = {
 730         .tag = TPM_TAG_RQU_COMMAND,
 731         .length = cpu_to_be32(14),
 732         .ordinal = TPM_ORDINAL_PCRREAD
 733 };
 734
 735 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 736 {
 737         int rc;
 738         struct tpm_cmd_t cmd;
 739
 740         cmd.header.in = pcrread_header;
 741         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 742         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 743                           "attempting to read a pcr value");
 744
 745         if (rc == 0)
 746                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 747                        TPM_DIGEST_SIZE);
 748         return rc;
 749 }
 750
 751 /**
 752  * tpm_pcr_read - read a pcr value
 753  * @chip_num:   tpm idx # or ANY
 754  * @pcr_idx:    pcr idx to retrieve
 755  * @res_buf:    TPM_PCR value
 756  *              size of res_buf is 20 bytes (or NULL if you don't care)
 757  *
 758  * The TPM driver should be built-in, but for whatever reason it
 759  * isn't, protect against the chip disappearing, by incrementing
 760  * the module usage count.
 761  */
 762 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 763 {
 764         struct tpm_chip *chip;
 765         int rc;
 766
 767         chip = tpm_chip_find_get(chip_num);
 768         if (chip == NULL)
 769                 return -ENODEV;
 770         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 771         tpm_chip_put(chip);
 772         return rc;
 773 }
 774 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 775
 776 /**
 777  * tpm_pcr_extend - extend pcr value with hash
 778  * @chip_num:   tpm idx # or AN&
 779  * @pcr_idx:    pcr idx to extend
 780  * @hash:       hash value used to extend pcr value
 781  *
 782  * The TPM driver should be built-in, but for whatever reason it
 783  * isn't, protect against the chip disappearing, by incrementing
 784  * the module usage count.
 785  */
 786 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 787 #define EXTEND_PCR_RESULT_SIZE 34
 788 static struct tpm_input_header pcrextend_header = {
 789         .tag = TPM_TAG_RQU_COMMAND,
 790         .length = cpu_to_be32(34),
 791         .ordinal = TPM_ORD_PCR_EXTEND
 792 };
 793
 794 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 795 {
 796         struct tpm_cmd_t cmd;
 797         int rc;
 798         struct tpm_chip *chip;
 799
 800         chip = tpm_chip_find_get(chip_num);
 801         if (chip == NULL)
 802                 return -ENODEV;
 803
 804         cmd.header.in = pcrextend_header;
 805         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 806         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 807         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 808                           "attempting extend a PCR value");
 809
 810         tpm_chip_put(chip);
 811         return rc;
 812 }
 813 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 814
 815 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 816 {
 817         struct tpm_chip *chip;
 818         int rc;
 819
 820         chip = tpm_chip_find_get(chip_num);
 821         if (chip == NULL)
 822                 return -ENODEV;
 823
 824         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 825
 826         tpm_chip_put(chip);
 827         return rc;
 828 }
 829 EXPORT_SYMBOL_GPL(tpm_send);
 830
 831 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 832                       char *buf)
 833 {
 834         cap_t cap;
 835         u8 digest[TPM_DIGEST_SIZE];
 836         ssize_t rc;
 837         int i, j, num_pcrs;
 838         char *str = buf;
 839         struct tpm_chip *chip = dev_get_drvdata(dev);
 840
 841         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 842                         "attempting to determine the number of PCRS");
 843         if (rc)
 844                 return 0;
 845
 846         num_pcrs = be32_to_cpu(cap.num_pcrs);
 847         for (i = 0; i < num_pcrs; i++) {
 848                 rc = __tpm_pcr_read(chip, i, digest);
 849                 if (rc)
 850                         break;
 851                 str += sprintf(str, "PCR-%02d: ", i);
 852                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 853                         str += sprintf(str, "%02X ", digest[j]);
 854                 str += sprintf(str, "\n");
 855         }
 856         return str - buf;
 857 }
 858 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 859
 860 #define  READ_PUBEK_RESULT_SIZE 314
 861 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 862 struct tpm_input_header tpm_readpubek_header = {
 863         .tag = TPM_TAG_RQU_COMMAND,
 864         .length = cpu_to_be32(30),
 865         .ordinal = TPM_ORD_READPUBEK
 866 };
 867
 868 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 869                        char *buf)
 870 {
 871         u8 *data;
 872         struct tpm_cmd_t tpm_cmd;
 873         ssize_t err;
 874         int i, rc;
 875         char *str = buf;
 876
 877         struct tpm_chip *chip = dev_get_drvdata(dev);
 878
 879         tpm_cmd.header.in = tpm_readpubek_header;
 880         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 881                         "attempting to read the PUBEK");
 882         if (err)
 883                 goto out;
 884
 885         /*
 886            ignore header 10 bytes
 887            algorithm 32 bits (1 == RSA )
 888            encscheme 16 bits
 889            sigscheme 16 bits
 890            parameters (RSA 12->bytes: keybit, #primes, expbit)
 891            keylenbytes 32 bits
 892            256 byte modulus
 893            ignore checksum 20 bytes
 894          */
 895         data = tpm_cmd.params.readpubek_out_buffer;
 896         str +=
 897             sprintf(str,
 898                     "Algorithm: %02X %02X %02X %02X\n"
 899                     "Encscheme: %02X %02X\n"
 900                     "Sigscheme: %02X %02X\n"
 901                     "Parameters: %02X %02X %02X %02X "
 902                     "%02X %02X %02X %02X "
 903                     "%02X %02X %02X %02X\n"
 904                     "Modulus length: %d\n"
 905                     "Modulus:\n",
 906                     data[0], data[1], data[2], data[3],
 907                     data[4], data[5],
 908                     data[6], data[7],
 909                     data[12], data[13], data[14], data[15],
 910                     data[16], data[17], data[18], data[19],
 911                     data[20], data[21], data[22], data[23],
 912                     be32_to_cpu(*((__be32 *) (data + 24))));
 913
 914         for (i = 0; i < 256; i++) {
 915                 str += sprintf(str, "%02X ", data[i + 28]);
 916                 if ((i + 1) % 16 == 0)
 917                         str += sprintf(str, "\n");
 918         }
 919 out:
 920         rc = str - buf;
 921         return rc;
 922 }
 923 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 924
 925
 926 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 927                       char *buf)
 928 {
 929         cap_t cap;
 930         ssize_t rc;
 931         char *str = buf;
 932
 933         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 934                         "attempting to determine the manufacturer");
 935         if (rc)
 936                 return 0;
 937         str += sprintf(str, "Manufacturer: 0x%x\n",
 938                        be32_to_cpu(cap.manufacturer_id));
 939
 940         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
 941                         "attempting to determine the 1.1 version");
 942         if (rc)
 943                 return 0;
 944         str += sprintf(str,
 945                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 946                        cap.tpm_version.Major, cap.tpm_version.Minor,
 947                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
 948         return str - buf;
 949 }
 950 EXPORT_SYMBOL_GPL(tpm_show_caps);
 951
 952 ssize_t tpm_show_caps_1_2(struct device * dev,
 953                           struct device_attribute * attr, char *buf)
 954 {
 955         cap_t cap;
 956         ssize_t rc;
 957         char *str = buf;
 958
 959         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 960                         "attempting to determine the manufacturer");
 961         if (rc)
 962                 return 0;
 963         str += sprintf(str, "Manufacturer: 0x%x\n",
 964                        be32_to_cpu(cap.manufacturer_id));
 965         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
 966                          "attempting to determine the 1.2 version");
 967         if (rc)
 968                 return 0;
 969         str += sprintf(str,
 970                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 971                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
 972                        cap.tpm_version_1_2.revMajor,
 973                        cap.tpm_version_1_2.revMinor);
 974         return str - buf;
 975 }
 976 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 977
 978 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
 979                           char *buf)
 980 {
 981         struct tpm_chip *chip = dev_get_drvdata(dev);
 982
 983         if (chip->vendor.duration[TPM_LONG] == 0)
 984                 return 0;
 985
 986         return sprintf(buf, "%d %d %d [%s]\n",
 987                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
 988                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
 989                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
 990                        chip->vendor.duration_adjusted
 991                        ? "adjusted" : "original");
 992 }
 993 EXPORT_SYMBOL_GPL(tpm_show_durations);
 994
 995 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
 996                           char *buf)
 997 {
 998         struct tpm_chip *chip = dev_get_drvdata(dev);
 999
1000         return sprintf(buf, "%d %d %d %d [%s]\n",
1001                        jiffies_to_usecs(chip->vendor.timeout_a),
1002                        jiffies_to_usecs(chip->vendor.timeout_b),
1003                        jiffies_to_usecs(chip->vendor.timeout_c),
1004                        jiffies_to_usecs(chip->vendor.timeout_d),
1005                        chip->vendor.timeout_adjusted
1006                        ? "adjusted" : "original");
1007 }
1008 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1009
1010 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1011                         const char *buf, size_t count)
1012 {
1013         struct tpm_chip *chip = dev_get_drvdata(dev);
1014         if (chip == NULL)
1015                 return 0;
1016
1017         chip->vendor.cancel(chip);
1018         return count;
1019 }
1020 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1021
1022 /*
1023  * Device file system interface to the TPM
1024  *
1025  * It's assured that the chip will be opened just once,
1026  * by the check of is_open variable, which is protected
1027  * by driver_lock.
1028  */
1029 int tpm_open(struct inode *inode, struct file *file)
1030 {
1031         int minor = iminor(inode);
1032         struct tpm_chip *chip = NULL, *pos;
1033
1034         rcu_read_lock();
1035         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1036                 if (pos->vendor.miscdev.minor == minor) {
1037                         chip = pos;
1038                         get_device(chip->dev);
1039                         break;
1040                 }
1041         }
1042         rcu_read_unlock();
1043
1044         if (!chip)
1045                 return -ENODEV;
1046
1047         if (test_and_set_bit(0, &chip->is_open)) {
1048                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1049                 put_device(chip->dev);
1050                 return -EBUSY;
1051         }
1052
1053         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1054         if (chip->data_buffer == NULL) {
1055                 clear_bit(0, &chip->is_open);
1056                 put_device(chip->dev);
1057                 return -ENOMEM;
1058         }
1059
1060         atomic_set(&chip->data_pending, 0);
1061
1062         file->private_data = chip;
1063         return 0;
1064 }
1065 EXPORT_SYMBOL_GPL(tpm_open);
1066
1067 /*
1068  * Called on file close
1069  */
1070 int tpm_release(struct inode *inode, struct file *file)
1071 {
1072         struct tpm_chip *chip = file->private_data;
1073
1074         del_singleshot_timer_sync(&chip->user_read_timer);
1075         flush_work_sync(&chip->work);
1076         file->private_data = NULL;
1077         atomic_set(&chip->data_pending, 0);
1078         kfree(chip->data_buffer);
1079         clear_bit(0, &chip->is_open);
1080         put_device(chip->dev);
1081         return 0;
1082 }
1083 EXPORT_SYMBOL_GPL(tpm_release);
1084
1085 ssize_t tpm_write(struct file *file, const char __user *buf,
1086                   size_t size, loff_t *off)
1087 {
1088         struct tpm_chip *chip = file->private_data;
1089         size_t in_size = size, out_size;
1090
1091         /* cannot perform a write until the read has cleared
1092            either via tpm_read or a user_read_timer timeout */
1093         while (atomic_read(&chip->data_pending) != 0)
1094                 msleep(TPM_TIMEOUT);
1095
1096         mutex_lock(&chip->buffer_mutex);
1097
1098         if (in_size > TPM_BUFSIZE)
1099                 in_size = TPM_BUFSIZE;
1100
1101         if (copy_from_user
1102             (chip->data_buffer, (void __user *) buf, in_size)) {
1103                 mutex_unlock(&chip->buffer_mutex);
1104                 return -EFAULT;
1105         }
1106
1107         /* atomic tpm command send and result receive */
1108         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1109
1110         atomic_set(&chip->data_pending, out_size);
1111         mutex_unlock(&chip->buffer_mutex);
1112
1113         /* Set a timeout by which the reader must come claim the result */
1114         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1115
1116         return in_size;
1117 }
1118 EXPORT_SYMBOL_GPL(tpm_write);
1119
1120 ssize_t tpm_read(struct file *file, char __user *buf,
1121                  size_t size, loff_t *off)
1122 {
1123         struct tpm_chip *chip = file->private_data;
1124         ssize_t ret_size;
1125
1126         del_singleshot_timer_sync(&chip->user_read_timer);
1127         flush_work_sync(&chip->work);
1128         ret_size = atomic_read(&chip->data_pending);
1129         atomic_set(&chip->data_pending, 0);
1130         if (ret_size > 0) {     /* relay data */
1131                 if (size < ret_size)
1132                         ret_size = size;
1133
1134                 mutex_lock(&chip->buffer_mutex);
1135                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1136                         ret_size = -EFAULT;
1137                 mutex_unlock(&chip->buffer_mutex);
1138         }
1139
1140         return ret_size;
1141 }
1142 EXPORT_SYMBOL_GPL(tpm_read);
1143
1144 void tpm_remove_hardware(struct device *dev)
1145 {
1146         struct tpm_chip *chip = dev_get_drvdata(dev);
1147
1148         if (chip == NULL) {
1149                 dev_err(dev, "No device data found\n");
1150                 return;
1151         }
1152
1153         spin_lock(&driver_lock);
1154         list_del_rcu(&chip->list);
1155         spin_unlock(&driver_lock);
1156         synchronize_rcu();
1157
1158         misc_deregister(&chip->vendor.miscdev);
1159         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1160         tpm_bios_log_teardown(chip->bios_dir);
1161
1162         /* write it this way to be explicit (chip->dev == dev) */
1163         put_device(chip->dev);
1164 }
1165 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1166
1167 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1168 #define SAVESTATE_RESULT_SIZE 10
1169
1170 static struct tpm_input_header savestate_header = {
1171         .tag = TPM_TAG_RQU_COMMAND,
1172         .length = cpu_to_be32(10),
1173         .ordinal = TPM_ORD_SAVESTATE
1174 };
1175
1176 /*
1177  * We are about to suspend. Save the TPM state
1178  * so that it can be restored.
1179  */
1180 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1181 {
1182         struct tpm_chip *chip = dev_get_drvdata(dev);
1183         struct tpm_cmd_t cmd;
1184         int rc;
1185
1186         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1187
1188         if (chip == NULL)
1189                 return -ENODEV;
1190
1191         /* for buggy tpm, flush pcrs with extend to selected dummy */
1192         if (tpm_suspend_pcr) {
1193                 cmd.header.in = pcrextend_header;
1194                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1195                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1196                        TPM_DIGEST_SIZE);
1197                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1198                                   "extending dummy pcr before suspend");
1199         }
1200
1201         /* now do the actual savestate */
1202         cmd.header.in = savestate_header;
1203         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1204                           "sending savestate before suspend");
1205         return rc;
1206 }
1207 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1208
1209 /*
1210  * Resume from a power safe. The BIOS already restored
1211  * the TPM state.
1212  */
1213 int tpm_pm_resume(struct device *dev)
1214 {
1215         struct tpm_chip *chip = dev_get_drvdata(dev);
1216
1217         if (chip == NULL)
1218                 return -ENODEV;
1219
1220         return 0;
1221 }
1222 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1223
1224 /* In case vendor provided release function, call it too.*/
1225
1226 void tpm_dev_vendor_release(struct tpm_chip *chip)
1227 {
1228         if (chip->vendor.release)
1229                 chip->vendor.release(chip->dev);
1230
1231         clear_bit(chip->dev_num, dev_mask);
1232         kfree(chip->vendor.miscdev.name);
1233 }
1234 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1235
1236
1237 /*
1238  * Once all references to platform device are down to 0,
1239  * release all allocated structures.
1240  */
1241 void tpm_dev_release(struct device *dev)
1242 {
1243         struct tpm_chip *chip = dev_get_drvdata(dev);
1244
1245         tpm_dev_vendor_release(chip);
1246
1247         chip->release(dev);
1248         kfree(chip);
1249 }
1250 EXPORT_SYMBOL_GPL(tpm_dev_release);
1251
1252 /*
1253  * Called from tpm_<specific>.c probe function only for devices
1254  * the driver has determined it should claim.  Prior to calling
1255  * this function the specific probe function has called pci_enable_device
1256  * upon errant exit from this function specific probe function should call
1257  * pci_disable_device
1258  */
1259 struct tpm_chip *tpm_register_hardware(struct device *dev,
1260                                         const struct tpm_vendor_specific *entry)
1261 {
1262 #define DEVNAME_SIZE 7
1263
1264         char *devname;
1265         struct tpm_chip *chip;
1266
1267         /* Driver specific per-device data */
1268         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1269         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1270
1271         if (chip == NULL || devname == NULL)
1272                 goto out_free;
1273
1274         mutex_init(&chip->buffer_mutex);
1275         mutex_init(&chip->tpm_mutex);
1276         INIT_LIST_HEAD(&chip->list);
1277
1278         INIT_WORK(&chip->work, timeout_work);
1279
1280         setup_timer(&chip->user_read_timer, user_reader_timeout,
1281                         (unsigned long)chip);
1282
1283         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1284
1285         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1286
1287         if (chip->dev_num >= TPM_NUM_DEVICES) {
1288                 dev_err(dev, "No available tpm device numbers\n");
1289                 goto out_free;
1290         } else if (chip->dev_num == 0)
1291                 chip->vendor.miscdev.minor = TPM_MINOR;
1292         else
1293                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1294
1295         set_bit(chip->dev_num, dev_mask);
1296
1297         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1298         chip->vendor.miscdev.name = devname;
1299
1300         chip->vendor.miscdev.parent = dev;
1301         chip->dev = get_device(dev);
1302         chip->release = dev->release;
1303         dev->release = tpm_dev_release;
1304         dev_set_drvdata(dev, chip);
1305
1306         if (misc_register(&chip->vendor.miscdev)) {
1307                 dev_err(chip->dev,
1308                         "unable to misc_register %s, minor %d\n",
1309                         chip->vendor.miscdev.name,
1310                         chip->vendor.miscdev.minor);
1311                 put_device(chip->dev);
1312                 return NULL;
1313         }
1314
1315         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1316                 misc_deregister(&chip->vendor.miscdev);
1317                 put_device(chip->dev);
1318
1319                 return NULL;
1320         }
1321
1322         chip->bios_dir = tpm_bios_log_setup(devname);
1323
1324         /* Make chip available */
1325         spin_lock(&driver_lock);
1326         list_add_rcu(&chip->list, &tpm_chip_list);
1327         spin_unlock(&driver_lock);
1328
1329         return chip;
1330
1331 out_free:
1332         kfree(chip);
1333         kfree(devname);
1334         return NULL;
1335 }
1336 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1337
1338 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1339 MODULE_DESCRIPTION("TPM Driver");
1340 MODULE_VERSION("2.0");
1341 MODULE_LICENSE("GPL");