drivers/char/tpm/tpm-interface.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 #include <linux/freezer.h>
  31
  32 #include "tpm.h"
  33 #include "tpm_eventlog.h"
  34
  35 enum tpm_duration {
  36         TPM_SHORT = 0,
  37         TPM_MEDIUM = 1,
  38         TPM_LONG = 2,
  39         TPM_UNDEFINED,
  40 };
  41
  42 #define TPM_MAX_ORDINAL 243
  43 #define TSC_MAX_ORDINAL 12
  44 #define TPM_PROTECTED_COMMAND 0x00
  45 #define TPM_CONNECTION_COMMAND 0x40
  46
  47 /*
  48  * Bug workaround - some TPM's don't flush the most
  49  * recently changed pcr on suspend, so force the flush
  50  * with an extend to the selected _unused_ non-volatile pcr.
  51  */
  52 static int tpm_suspend_pcr;
  53 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  54 MODULE_PARM_DESC(suspend_pcr,
  55                  "PCR to use for dummy writes to faciltate flush on suspend.");
  56
  57 static LIST_HEAD(tpm_chip_list);
  58 static DEFINE_SPINLOCK(driver_lock);
  59 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  60
  61 /*
  62  * Array with one entry per ordinal defining the maximum amount
  63  * of time the chip could take to return the result.  The ordinal
  64  * designation of short, medium or long is defined in a table in
  65  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  66  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  67  * from the chip during initialization with a call to tpm_get_timeouts.
  68  */
  69 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  70         TPM_UNDEFINED,          /* 0 */
  71         TPM_UNDEFINED,
  72         TPM_UNDEFINED,
  73         TPM_UNDEFINED,
  74         TPM_UNDEFINED,
  75         TPM_UNDEFINED,          /* 5 */
  76         TPM_UNDEFINED,
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,
  79         TPM_UNDEFINED,
  80         TPM_SHORT,              /* 10 */
  81         TPM_SHORT,
  82         TPM_MEDIUM,
  83         TPM_LONG,
  84         TPM_LONG,
  85         TPM_MEDIUM,             /* 15 */
  86         TPM_SHORT,
  87         TPM_SHORT,
  88         TPM_MEDIUM,
  89         TPM_LONG,
  90         TPM_SHORT,              /* 20 */
  91         TPM_SHORT,
  92         TPM_MEDIUM,
  93         TPM_MEDIUM,
  94         TPM_MEDIUM,
  95         TPM_SHORT,              /* 25 */
  96         TPM_SHORT,
  97         TPM_MEDIUM,
  98         TPM_SHORT,
  99         TPM_SHORT,
 100         TPM_MEDIUM,             /* 30 */
 101         TPM_LONG,
 102         TPM_MEDIUM,
 103         TPM_SHORT,
 104         TPM_SHORT,
 105         TPM_SHORT,              /* 35 */
 106         TPM_MEDIUM,
 107         TPM_MEDIUM,
 108         TPM_UNDEFINED,
 109         TPM_UNDEFINED,
 110         TPM_MEDIUM,             /* 40 */
 111         TPM_LONG,
 112         TPM_MEDIUM,
 113         TPM_SHORT,
 114         TPM_SHORT,
 115         TPM_SHORT,              /* 45 */
 116         TPM_SHORT,
 117         TPM_SHORT,
 118         TPM_SHORT,
 119         TPM_LONG,
 120         TPM_MEDIUM,             /* 50 */
 121         TPM_MEDIUM,
 122         TPM_UNDEFINED,
 123         TPM_UNDEFINED,
 124         TPM_UNDEFINED,
 125         TPM_UNDEFINED,          /* 55 */
 126         TPM_UNDEFINED,
 127         TPM_UNDEFINED,
 128         TPM_UNDEFINED,
 129         TPM_UNDEFINED,
 130         TPM_MEDIUM,             /* 60 */
 131         TPM_MEDIUM,
 132         TPM_MEDIUM,
 133         TPM_SHORT,
 134         TPM_SHORT,
 135         TPM_MEDIUM,             /* 65 */
 136         TPM_UNDEFINED,
 137         TPM_UNDEFINED,
 138         TPM_UNDEFINED,
 139         TPM_UNDEFINED,
 140         TPM_SHORT,              /* 70 */
 141         TPM_SHORT,
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,          /* 75 */
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_UNDEFINED,
 149         TPM_UNDEFINED,
 150         TPM_LONG,               /* 80 */
 151         TPM_UNDEFINED,
 152         TPM_MEDIUM,
 153         TPM_LONG,
 154         TPM_SHORT,
 155         TPM_UNDEFINED,          /* 85 */
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_UNDEFINED,
 159         TPM_UNDEFINED,
 160         TPM_SHORT,              /* 90 */
 161         TPM_SHORT,
 162         TPM_SHORT,
 163         TPM_SHORT,
 164         TPM_SHORT,
 165         TPM_UNDEFINED,          /* 95 */
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_UNDEFINED,
 169         TPM_UNDEFINED,
 170         TPM_MEDIUM,             /* 100 */
 171         TPM_SHORT,
 172         TPM_SHORT,
 173         TPM_UNDEFINED,
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,          /* 105 */
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_UNDEFINED,
 179         TPM_UNDEFINED,
 180         TPM_SHORT,              /* 110 */
 181         TPM_SHORT,
 182         TPM_SHORT,
 183         TPM_SHORT,
 184         TPM_SHORT,
 185         TPM_SHORT,              /* 115 */
 186         TPM_SHORT,
 187         TPM_SHORT,
 188         TPM_UNDEFINED,
 189         TPM_UNDEFINED,
 190         TPM_LONG,               /* 120 */
 191         TPM_LONG,
 192         TPM_MEDIUM,
 193         TPM_UNDEFINED,
 194         TPM_SHORT,
 195         TPM_SHORT,              /* 125 */
 196         TPM_SHORT,
 197         TPM_LONG,
 198         TPM_SHORT,
 199         TPM_SHORT,
 200         TPM_SHORT,              /* 130 */
 201         TPM_MEDIUM,
 202         TPM_UNDEFINED,
 203         TPM_SHORT,
 204         TPM_MEDIUM,
 205         TPM_UNDEFINED,          /* 135 */
 206         TPM_UNDEFINED,
 207         TPM_UNDEFINED,
 208         TPM_UNDEFINED,
 209         TPM_UNDEFINED,
 210         TPM_SHORT,              /* 140 */
 211         TPM_SHORT,
 212         TPM_UNDEFINED,
 213         TPM_UNDEFINED,
 214         TPM_UNDEFINED,
 215         TPM_UNDEFINED,          /* 145 */
 216         TPM_UNDEFINED,
 217         TPM_UNDEFINED,
 218         TPM_UNDEFINED,
 219         TPM_UNDEFINED,
 220         TPM_SHORT,              /* 150 */
 221         TPM_MEDIUM,
 222         TPM_MEDIUM,
 223         TPM_SHORT,
 224         TPM_SHORT,
 225         TPM_UNDEFINED,          /* 155 */
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_UNDEFINED,
 229         TPM_UNDEFINED,
 230         TPM_SHORT,              /* 160 */
 231         TPM_SHORT,
 232         TPM_SHORT,
 233         TPM_SHORT,
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,          /* 165 */
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_UNDEFINED,
 239         TPM_UNDEFINED,
 240         TPM_LONG,               /* 170 */
 241         TPM_UNDEFINED,
 242         TPM_UNDEFINED,
 243         TPM_UNDEFINED,
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,          /* 175 */
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_UNDEFINED,
 249         TPM_UNDEFINED,
 250         TPM_MEDIUM,             /* 180 */
 251         TPM_SHORT,
 252         TPM_MEDIUM,
 253         TPM_MEDIUM,
 254         TPM_MEDIUM,
 255         TPM_MEDIUM,             /* 185 */
 256         TPM_SHORT,
 257         TPM_UNDEFINED,
 258         TPM_UNDEFINED,
 259         TPM_UNDEFINED,
 260         TPM_UNDEFINED,          /* 190 */
 261         TPM_UNDEFINED,
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,          /* 195 */
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_UNDEFINED,
 269         TPM_UNDEFINED,
 270         TPM_SHORT,              /* 200 */
 271         TPM_UNDEFINED,
 272         TPM_UNDEFINED,
 273         TPM_UNDEFINED,
 274         TPM_SHORT,
 275         TPM_SHORT,              /* 205 */
 276         TPM_SHORT,
 277         TPM_SHORT,
 278         TPM_SHORT,
 279         TPM_SHORT,
 280         TPM_MEDIUM,             /* 210 */
 281         TPM_UNDEFINED,
 282         TPM_MEDIUM,
 283         TPM_MEDIUM,
 284         TPM_MEDIUM,
 285         TPM_UNDEFINED,          /* 215 */
 286         TPM_MEDIUM,
 287         TPM_UNDEFINED,
 288         TPM_UNDEFINED,
 289         TPM_SHORT,
 290         TPM_SHORT,              /* 220 */
 291         TPM_SHORT,
 292         TPM_SHORT,
 293         TPM_SHORT,
 294         TPM_SHORT,
 295         TPM_UNDEFINED,          /* 225 */
 296         TPM_UNDEFINED,
 297         TPM_UNDEFINED,
 298         TPM_UNDEFINED,
 299         TPM_UNDEFINED,
 300         TPM_SHORT,              /* 230 */
 301         TPM_LONG,
 302         TPM_MEDIUM,
 303         TPM_UNDEFINED,
 304         TPM_UNDEFINED,
 305         TPM_UNDEFINED,          /* 235 */
 306         TPM_UNDEFINED,
 307         TPM_UNDEFINED,
 308         TPM_UNDEFINED,
 309         TPM_UNDEFINED,
 310         TPM_SHORT,              /* 240 */
 311         TPM_UNDEFINED,
 312         TPM_MEDIUM,
 313 };
 314
 315 /*
 316  * Returns max number of jiffies to wait
 317  */
 318 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 319                                            u32 ordinal)
 320 {
 321         int duration_idx = TPM_UNDEFINED;
 322         int duration = 0;
 323         u8 category = (ordinal >> 24) & 0xFF;
 324
 325         if ((category == TPM_PROTECTED_COMMAND && ordinal < TPM_MAX_ORDINAL) ||
 326             (category == TPM_CONNECTION_COMMAND && ordinal < TSC_MAX_ORDINAL))
 327                 duration_idx = tpm_ordinal_duration[ordinal];
 328
 329         if (duration_idx != TPM_UNDEFINED)
 330                 duration = chip->vendor.duration[duration_idx];
 331         if (duration <= 0)
 332                 return 2 * 60 * HZ;
 333         else
 334                 return duration;
 335 }
 336 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 337
 338 /*
 339  * Internal kernel interface to transmit TPM commands
 340  */
 341 ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 342                      size_t bufsiz)
 343 {
 344         ssize_t rc;
 345         u32 count, ordinal;
 346         unsigned long stop;
 347
 348         if (bufsiz > TPM_BUFSIZE)
 349                 bufsiz = TPM_BUFSIZE;
 350
 351         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 352         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 353         if (count == 0)
 354                 return -ENODATA;
 355         if (count > bufsiz) {
 356                 dev_err(chip->dev,
 357                         "invalid count value %x %zx\n", count, bufsiz);
 358                 return -E2BIG;
 359         }
 360
 361         mutex_lock(&chip->tpm_mutex);
 362
 363         rc = chip->vendor.send(chip, (u8 *) buf, count);
 364         if (rc < 0) {
 365                 dev_err(chip->dev,
 366                         "tpm_transmit: tpm_send: error %zd\n", rc);
 367                 goto out;
 368         }
 369
 370         if (chip->vendor.irq)
 371                 goto out_recv;
 372
 373         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 374         do {
 375                 u8 status = chip->vendor.status(chip);
 376                 if ((status & chip->vendor.req_complete_mask) ==
 377                     chip->vendor.req_complete_val)
 378                         goto out_recv;
 379
 380                 if (chip->vendor.req_canceled(chip, status)) {
 381                         dev_err(chip->dev, "Operation Canceled\n");
 382                         rc = -ECANCELED;
 383                         goto out;
 384                 }
 385
 386                 msleep(TPM_TIMEOUT);    /* CHECK */
 387                 rmb();
 388         } while (time_before(jiffies, stop));
 389
 390         chip->vendor.cancel(chip);
 391         dev_err(chip->dev, "Operation Timed out\n");
 392         rc = -ETIME;
 393         goto out;
 394
 395 out_recv:
 396         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 397         if (rc < 0)
 398                 dev_err(chip->dev,
 399                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 400 out:
 401         mutex_unlock(&chip->tpm_mutex);
 402         return rc;
 403 }
 404
 405 #define TPM_DIGEST_SIZE 20
 406 #define TPM_RET_CODE_IDX 6
 407
 408 enum tpm_capabilities {
 409         TPM_CAP_FLAG = cpu_to_be32(4),
 410         TPM_CAP_PROP = cpu_to_be32(5),
 411         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 412         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 413 };
 414
 415 enum tpm_sub_capabilities {
 416         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 417         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 418         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 419         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 420         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 421         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 422         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 423
 424 };
 425
 426 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 427                             int len, const char *desc)
 428 {
 429         int err;
 430
 431         len = tpm_transmit(chip, (u8 *) cmd, len);
 432         if (len <  0)
 433                 return len;
 434         else if (len < TPM_HEADER_SIZE)
 435                 return -EFAULT;
 436
 437         err = be32_to_cpu(cmd->header.out.return_code);
 438         if (err != 0 && desc)
 439                 dev_err(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 440
 441         return err;
 442 }
 443
 444 #define TPM_INTERNAL_RESULT_SIZE 200
 445 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 446 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 447 #define TPM_ORD_GET_RANDOM cpu_to_be32(70)
 448
 449 static const struct tpm_input_header tpm_getcap_header = {
 450         .tag = TPM_TAG_RQU_COMMAND,
 451         .length = cpu_to_be32(22),
 452         .ordinal = TPM_ORD_GET_CAP
 453 };
 454
 455 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 456                    const char *desc)
 457 {
 458         struct tpm_cmd_t tpm_cmd;
 459         int rc;
 460         struct tpm_chip *chip = dev_get_drvdata(dev);
 461
 462         tpm_cmd.header.in = tpm_getcap_header;
 463         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 464                 tpm_cmd.params.getcap_in.cap = subcap_id;
 465                 /*subcap field not necessary */
 466                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 467                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 468         } else {
 469                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 470                     subcap_id == TPM_CAP_FLAG_VOL)
 471                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 472                 else
 473                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 474                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 475                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 476         }
 477         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 478         if (!rc)
 479                 *cap = tpm_cmd.params.getcap_out.cap;
 480         return rc;
 481 }
 482
 483 void tpm_gen_interrupt(struct tpm_chip *chip)
 484 {
 485         struct  tpm_cmd_t tpm_cmd;
 486         ssize_t rc;
 487
 488         tpm_cmd.header.in = tpm_getcap_header;
 489         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 490         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 491         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 492
 493         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 494                         "attempting to determine the timeouts");
 495 }
 496 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 497
 498 #define TPM_ORD_STARTUP cpu_to_be32(153)
 499 #define TPM_ST_CLEAR cpu_to_be16(1)
 500 #define TPM_ST_STATE cpu_to_be16(2)
 501 #define TPM_ST_DEACTIVATED cpu_to_be16(3)
 502 static const struct tpm_input_header tpm_startup_header = {
 503         .tag = TPM_TAG_RQU_COMMAND,
 504         .length = cpu_to_be32(12),
 505         .ordinal = TPM_ORD_STARTUP
 506 };
 507
 508 static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
 509 {
 510         struct tpm_cmd_t start_cmd;
 511         start_cmd.header.in = tpm_startup_header;
 512         start_cmd.params.startup_in.startup_type = startup_type;
 513         return transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
 514                             "attempting to start the TPM");
 515 }
 516
 517 int tpm_get_timeouts(struct tpm_chip *chip)
 518 {
 519         struct tpm_cmd_t tpm_cmd;
 520         struct timeout_t *timeout_cap;
 521         struct duration_t *duration_cap;
 522         ssize_t rc;
 523         u32 timeout;
 524         unsigned int scale = 1;
 525
 526         tpm_cmd.header.in = tpm_getcap_header;
 527         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 528         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 529         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 530         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
 531
 532         if (rc == TPM_ERR_INVALID_POSTINIT) {
 533                 /* The TPM is not started, we are the first to talk to it.
 534                    Execute a startup command. */
 535                 dev_info(chip->dev, "Issuing TPM_STARTUP");
 536                 if (tpm_startup(chip, TPM_ST_CLEAR))
 537                         return rc;
 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                 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 544                                   NULL);
 545         }
 546         if (rc) {
 547                 dev_err(chip->dev,
 548                         "A TPM error (%zd) occurred attempting to determine the timeouts\n",
 549                         rc);
 550                 goto duration;
 551         }
 552
 553         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 554             be32_to_cpu(tpm_cmd.header.out.length)
 555             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 556                 return -EINVAL;
 557
 558         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 559         /* Don't overwrite default if value is 0 */
 560         timeout = be32_to_cpu(timeout_cap->a);
 561         if (timeout && timeout < 1000) {
 562                 /* timeouts in msec rather usec */
 563                 scale = 1000;
 564                 chip->vendor.timeout_adjusted = true;
 565         }
 566         if (timeout)
 567                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 568         timeout = be32_to_cpu(timeout_cap->b);
 569         if (timeout)
 570                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 571         timeout = be32_to_cpu(timeout_cap->c);
 572         if (timeout)
 573                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 574         timeout = be32_to_cpu(timeout_cap->d);
 575         if (timeout)
 576                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 577
 578 duration:
 579         tpm_cmd.header.in = tpm_getcap_header;
 580         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 581         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 582         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 583
 584         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 585                         "attempting to determine the durations");
 586         if (rc)
 587                 return rc;
 588
 589         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 590             be32_to_cpu(tpm_cmd.header.out.length)
 591             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 592                 return -EINVAL;
 593
 594         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 595         chip->vendor.duration[TPM_SHORT] =
 596             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 597         chip->vendor.duration[TPM_MEDIUM] =
 598             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 599         chip->vendor.duration[TPM_LONG] =
 600             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 601
 602         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 603          * value wrong and apparently reports msecs rather than usecs. So we
 604          * fix up the resulting too-small TPM_SHORT value to make things work.
 605          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 606          */
 607         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 608                 chip->vendor.duration[TPM_SHORT] = HZ;
 609                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 610                 chip->vendor.duration[TPM_LONG] *= 1000;
 611                 chip->vendor.duration_adjusted = true;
 612                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 613         }
 614         return 0;
 615 }
 616 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 617
 618 #define TPM_ORD_CONTINUE_SELFTEST 83
 619 #define CONTINUE_SELFTEST_RESULT_SIZE 10
 620
 621 static struct tpm_input_header continue_selftest_header = {
 622         .tag = TPM_TAG_RQU_COMMAND,
 623         .length = cpu_to_be32(10),
 624         .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
 625 };
 626
 627 /**
 628  * tpm_continue_selftest -- run TPM's selftest
 629  * @chip: TPM chip to use
 630  *
 631  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 632  * a TPM error code.
 633  */
 634 static int tpm_continue_selftest(struct tpm_chip *chip)
 635 {
 636         int rc;
 637         struct tpm_cmd_t cmd;
 638
 639         cmd.header.in = continue_selftest_header;
 640         rc = transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
 641                           "continue selftest");
 642         return rc;
 643 }
 644
 645 ssize_t tpm_show_enabled(struct device *dev, struct device_attribute *attr,
 646                         char *buf)
 647 {
 648         cap_t cap;
 649         ssize_t rc;
 650
 651         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 652                          "attempting to determine the permanent enabled state");
 653         if (rc)
 654                 return 0;
 655
 656         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 657         return rc;
 658 }
 659 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 660
 661 ssize_t tpm_show_active(struct device *dev, struct device_attribute *attr,
 662                         char *buf)
 663 {
 664         cap_t cap;
 665         ssize_t rc;
 666
 667         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 668                          "attempting to determine the permanent active state");
 669         if (rc)
 670                 return 0;
 671
 672         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 673         return rc;
 674 }
 675 EXPORT_SYMBOL_GPL(tpm_show_active);
 676
 677 ssize_t tpm_show_owned(struct device *dev, struct device_attribute *attr,
 678                         char *buf)
 679 {
 680         cap_t cap;
 681         ssize_t rc;
 682
 683         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 684                          "attempting to determine the owner state");
 685         if (rc)
 686                 return 0;
 687
 688         rc = sprintf(buf, "%d\n", cap.owned);
 689         return rc;
 690 }
 691 EXPORT_SYMBOL_GPL(tpm_show_owned);
 692
 693 ssize_t tpm_show_temp_deactivated(struct device *dev,
 694                                 struct device_attribute *attr, char *buf)
 695 {
 696         cap_t cap;
 697         ssize_t rc;
 698
 699         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 700                          "attempting to determine the temporary state");
 701         if (rc)
 702                 return 0;
 703
 704         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 705         return rc;
 706 }
 707 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 708
 709 /*
 710  * tpm_chip_find_get - return tpm_chip for given chip number
 711  */
 712 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 713 {
 714         struct tpm_chip *pos, *chip = NULL;
 715
 716         rcu_read_lock();
 717         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 718                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 719                         continue;
 720
 721                 if (try_module_get(pos->dev->driver->owner)) {
 722                         chip = pos;
 723                         break;
 724                 }
 725         }
 726         rcu_read_unlock();
 727         return chip;
 728 }
 729
 730 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 731 #define READ_PCR_RESULT_SIZE 30
 732 static struct tpm_input_header pcrread_header = {
 733         .tag = TPM_TAG_RQU_COMMAND,
 734         .length = cpu_to_be32(14),
 735         .ordinal = TPM_ORDINAL_PCRREAD
 736 };
 737
 738 static int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 739 {
 740         int rc;
 741         struct tpm_cmd_t cmd;
 742
 743         cmd.header.in = pcrread_header;
 744         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 745         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 746                           "attempting to read a pcr value");
 747
 748         if (rc == 0)
 749                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 750                        TPM_DIGEST_SIZE);
 751         return rc;
 752 }
 753
 754 /**
 755  * tpm_pcr_read - read a pcr value
 756  * @chip_num:   tpm idx # or ANY
 757  * @pcr_idx:    pcr idx to retrieve
 758  * @res_buf:    TPM_PCR value
 759  *              size of res_buf is 20 bytes (or NULL if you don't care)
 760  *
 761  * The TPM driver should be built-in, but for whatever reason it
 762  * isn't, protect against the chip disappearing, by incrementing
 763  * the module usage count.
 764  */
 765 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 766 {
 767         struct tpm_chip *chip;
 768         int rc;
 769
 770         chip = tpm_chip_find_get(chip_num);
 771         if (chip == NULL)
 772                 return -ENODEV;
 773         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 774         tpm_chip_put(chip);
 775         return rc;
 776 }
 777 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 778
 779 /**
 780  * tpm_pcr_extend - extend pcr value with hash
 781  * @chip_num:   tpm idx # or AN&
 782  * @pcr_idx:    pcr idx to extend
 783  * @hash:       hash value used to extend pcr value
 784  *
 785  * The TPM driver should be built-in, but for whatever reason it
 786  * isn't, protect against the chip disappearing, by incrementing
 787  * the module usage count.
 788  */
 789 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 790 #define EXTEND_PCR_RESULT_SIZE 34
 791 static struct tpm_input_header pcrextend_header = {
 792         .tag = TPM_TAG_RQU_COMMAND,
 793         .length = cpu_to_be32(34),
 794         .ordinal = TPM_ORD_PCR_EXTEND
 795 };
 796
 797 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 798 {
 799         struct tpm_cmd_t cmd;
 800         int rc;
 801         struct tpm_chip *chip;
 802
 803         chip = tpm_chip_find_get(chip_num);
 804         if (chip == NULL)
 805                 return -ENODEV;
 806
 807         cmd.header.in = pcrextend_header;
 808         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 809         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 810         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 811                           "attempting extend a PCR value");
 812
 813         tpm_chip_put(chip);
 814         return rc;
 815 }
 816 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 817
 818 /**
 819  * tpm_do_selftest - have the TPM continue its selftest and wait until it
 820  *                   can receive further commands
 821  * @chip: TPM chip to use
 822  *
 823  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
 824  * a TPM error code.
 825  */
 826 int tpm_do_selftest(struct tpm_chip *chip)
 827 {
 828         int rc;
 829         unsigned int loops;
 830         unsigned int delay_msec = 100;
 831         unsigned long duration;
 832         struct tpm_cmd_t cmd;
 833
 834         duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
 835
 836         loops = jiffies_to_msecs(duration) / delay_msec;
 837
 838         rc = tpm_continue_selftest(chip);
 839         /* This may fail if there was no TPM driver during a suspend/resume
 840          * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
 841          */
 842         if (rc)
 843                 return rc;
 844
 845         do {
 846                 /* Attempt to read a PCR value */
 847                 cmd.header.in = pcrread_header;
 848                 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
 849                 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
 850                 /* Some buggy TPMs will not respond to tpm_tis_ready() for
 851                  * around 300ms while the self test is ongoing, keep trying
 852                  * until the self test duration expires. */
 853                 if (rc == -ETIME) {
 854                         dev_info(chip->dev, HW_ERR "TPM command timed out during continue self test");
 855                         msleep(delay_msec);
 856                         continue;
 857                 }
 858
 859                 if (rc < TPM_HEADER_SIZE)
 860                         return -EFAULT;
 861
 862                 rc = be32_to_cpu(cmd.header.out.return_code);
 863                 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
 864                         dev_info(chip->dev,
 865                                  "TPM is disabled/deactivated (0x%X)\n", rc);
 866                         /* TPM is disabled and/or deactivated; driver can
 867                          * proceed and TPM does handle commands for
 868                          * suspend/resume correctly
 869                          */
 870                         return 0;
 871                 }
 872                 if (rc != TPM_WARN_DOING_SELFTEST)
 873                         return rc;
 874                 msleep(delay_msec);
 875         } while (--loops > 0);
 876
 877         return rc;
 878 }
 879 EXPORT_SYMBOL_GPL(tpm_do_selftest);
 880
 881 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 882 {
 883         struct tpm_chip *chip;
 884         int rc;
 885
 886         chip = tpm_chip_find_get(chip_num);
 887         if (chip == NULL)
 888                 return -ENODEV;
 889
 890         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 891
 892         tpm_chip_put(chip);
 893         return rc;
 894 }
 895 EXPORT_SYMBOL_GPL(tpm_send);
 896
 897 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 898                       char *buf)
 899 {
 900         cap_t cap;
 901         u8 digest[TPM_DIGEST_SIZE];
 902         ssize_t rc;
 903         int i, j, num_pcrs;
 904         char *str = buf;
 905         struct tpm_chip *chip = dev_get_drvdata(dev);
 906
 907         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 908                         "attempting to determine the number of PCRS");
 909         if (rc)
 910                 return 0;
 911
 912         num_pcrs = be32_to_cpu(cap.num_pcrs);
 913         for (i = 0; i < num_pcrs; i++) {
 914                 rc = __tpm_pcr_read(chip, i, digest);
 915                 if (rc)
 916                         break;
 917                 str += sprintf(str, "PCR-%02d: ", i);
 918                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 919                         str += sprintf(str, "%02X ", digest[j]);
 920                 str += sprintf(str, "\n");
 921         }
 922         return str - buf;
 923 }
 924 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 925
 926 #define  READ_PUBEK_RESULT_SIZE 314
 927 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 928 static struct tpm_input_header tpm_readpubek_header = {
 929         .tag = TPM_TAG_RQU_COMMAND,
 930         .length = cpu_to_be32(30),
 931         .ordinal = TPM_ORD_READPUBEK
 932 };
 933
 934 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 935                        char *buf)
 936 {
 937         u8 *data;
 938         struct tpm_cmd_t tpm_cmd;
 939         ssize_t err;
 940         int i, rc;
 941         char *str = buf;
 942
 943         struct tpm_chip *chip = dev_get_drvdata(dev);
 944
 945         tpm_cmd.header.in = tpm_readpubek_header;
 946         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 947                         "attempting to read the PUBEK");
 948         if (err)
 949                 goto out;
 950
 951         /*
 952            ignore header 10 bytes
 953            algorithm 32 bits (1 == RSA )
 954            encscheme 16 bits
 955            sigscheme 16 bits
 956            parameters (RSA 12->bytes: keybit, #primes, expbit)
 957            keylenbytes 32 bits
 958            256 byte modulus
 959            ignore checksum 20 bytes
 960          */
 961         data = tpm_cmd.params.readpubek_out_buffer;
 962         str +=
 963             sprintf(str,
 964                     "Algorithm: %02X %02X %02X %02X\n"
 965                     "Encscheme: %02X %02X\n"
 966                     "Sigscheme: %02X %02X\n"
 967                     "Parameters: %02X %02X %02X %02X "
 968                     "%02X %02X %02X %02X "
 969                     "%02X %02X %02X %02X\n"
 970                     "Modulus length: %d\n"
 971                     "Modulus:\n",
 972                     data[0], data[1], data[2], data[3],
 973                     data[4], data[5],
 974                     data[6], data[7],
 975                     data[12], data[13], data[14], data[15],
 976                     data[16], data[17], data[18], data[19],
 977                     data[20], data[21], data[22], data[23],
 978                     be32_to_cpu(*((__be32 *) (data + 24))));
 979
 980         for (i = 0; i < 256; i++) {
 981                 str += sprintf(str, "%02X ", data[i + 28]);
 982                 if ((i + 1) % 16 == 0)
 983                         str += sprintf(str, "\n");
 984         }
 985 out:
 986         rc = str - buf;
 987         return rc;
 988 }
 989 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 990
 991
 992 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 993                       char *buf)
 994 {
 995         cap_t cap;
 996         ssize_t rc;
 997         char *str = buf;
 998
 999         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
1000                         "attempting to determine the manufacturer");
1001         if (rc)
1002                 return 0;
1003         str += sprintf(str, "Manufacturer: 0x%x\n",
1004                        be32_to_cpu(cap.manufacturer_id));
1005
1006         /* Try to get a TPM version 1.2 TPM_CAP_VERSION_INFO */
1007         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
1008                          "attempting to determine the 1.2 version");
1009         if (!rc) {
1010                 str += sprintf(str,
1011                                "TCG version: %d.%d\nFirmware version: %d.%d\n",
1012                                cap.tpm_version_1_2.Major,
1013                                cap.tpm_version_1_2.Minor,
1014                                cap.tpm_version_1_2.revMajor,
1015                                cap.tpm_version_1_2.revMinor);
1016         } else {
1017                 /* Otherwise just use TPM_STRUCT_VER */
1018                 rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
1019                                 "attempting to determine the 1.1 version");
1020                 if (rc)
1021                         return 0;
1022                 str += sprintf(str,
1023                                "TCG version: %d.%d\nFirmware version: %d.%d\n",
1024                                cap.tpm_version.Major,
1025                                cap.tpm_version.Minor,
1026                                cap.tpm_version.revMajor,
1027                                cap.tpm_version.revMinor);
1028         }
1029
1030         return str - buf;
1031 }
1032 EXPORT_SYMBOL_GPL(tpm_show_caps);
1033
1034 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
1035                           char *buf)
1036 {
1037         struct tpm_chip *chip = dev_get_drvdata(dev);
1038
1039         if (chip->vendor.duration[TPM_LONG] == 0)
1040                 return 0;
1041
1042         return sprintf(buf, "%d %d %d [%s]\n",
1043                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
1044                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
1045                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
1046                        chip->vendor.duration_adjusted
1047                        ? "adjusted" : "original");
1048 }
1049 EXPORT_SYMBOL_GPL(tpm_show_durations);
1050
1051 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
1052                           char *buf)
1053 {
1054         struct tpm_chip *chip = dev_get_drvdata(dev);
1055
1056         return sprintf(buf, "%d %d %d %d [%s]\n",
1057                        jiffies_to_usecs(chip->vendor.timeout_a),
1058                        jiffies_to_usecs(chip->vendor.timeout_b),
1059                        jiffies_to_usecs(chip->vendor.timeout_c),
1060                        jiffies_to_usecs(chip->vendor.timeout_d),
1061                        chip->vendor.timeout_adjusted
1062                        ? "adjusted" : "original");
1063 }
1064 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
1065
1066 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
1067                         const char *buf, size_t count)
1068 {
1069         struct tpm_chip *chip = dev_get_drvdata(dev);
1070         if (chip == NULL)
1071                 return 0;
1072
1073         chip->vendor.cancel(chip);
1074         return count;
1075 }
1076 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1077
1078 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
1079                                         bool check_cancel, bool *canceled)
1080 {
1081         u8 status = chip->vendor.status(chip);
1082
1083         *canceled = false;
1084         if ((status & mask) == mask)
1085                 return true;
1086         if (check_cancel && chip->vendor.req_canceled(chip, status)) {
1087                 *canceled = true;
1088                 return true;
1089         }
1090         return false;
1091 }
1092
1093 int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
1094                       wait_queue_head_t *queue, bool check_cancel)
1095 {
1096         unsigned long stop;
1097         long rc;
1098         u8 status;
1099         bool canceled = false;
1100
1101         /* check current status */
1102         status = chip->vendor.status(chip);
1103         if ((status & mask) == mask)
1104                 return 0;
1105
1106         stop = jiffies + timeout;
1107
1108         if (chip->vendor.irq) {
1109 again:
1110                 timeout = stop - jiffies;
1111                 if ((long)timeout <= 0)
1112                         return -ETIME;
1113                 rc = wait_event_interruptible_timeout(*queue,
1114                         wait_for_tpm_stat_cond(chip, mask, check_cancel,
1115                                                &canceled),
1116                         timeout);
1117                 if (rc > 0) {
1118                         if (canceled)
1119                                 return -ECANCELED;
1120                         return 0;
1121                 }
1122                 if (rc == -ERESTARTSYS && freezing(current)) {
1123                         clear_thread_flag(TIF_SIGPENDING);
1124                         goto again;
1125                 }
1126         } else {
1127                 do {
1128                         msleep(TPM_TIMEOUT);
1129                         status = chip->vendor.status(chip);
1130                         if ((status & mask) == mask)
1131                                 return 0;
1132                 } while (time_before(jiffies, stop));
1133         }
1134         return -ETIME;
1135 }
1136 EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1137
1138 void tpm_remove_hardware(struct device *dev)
1139 {
1140         struct tpm_chip *chip = dev_get_drvdata(dev);
1141
1142         if (chip == NULL) {
1143                 dev_err(dev, "No device data found\n");
1144                 return;
1145         }
1146
1147         spin_lock(&driver_lock);
1148         list_del_rcu(&chip->list);
1149         spin_unlock(&driver_lock);
1150         synchronize_rcu();
1151
1152         tpm_dev_del_device(chip);
1153         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1154         tpm_remove_ppi(&dev->kobj);
1155         tpm_bios_log_teardown(chip->bios_dir);
1156
1157         /* write it this way to be explicit (chip->dev == dev) */
1158         put_device(chip->dev);
1159 }
1160 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1161
1162 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1163 #define SAVESTATE_RESULT_SIZE 10
1164
1165 static struct tpm_input_header savestate_header = {
1166         .tag = TPM_TAG_RQU_COMMAND,
1167         .length = cpu_to_be32(10),
1168         .ordinal = TPM_ORD_SAVESTATE
1169 };
1170
1171 /*
1172  * We are about to suspend. Save the TPM state
1173  * so that it can be restored.
1174  */
1175 int tpm_pm_suspend(struct device *dev)
1176 {
1177         struct tpm_chip *chip = dev_get_drvdata(dev);
1178         struct tpm_cmd_t cmd;
1179         int rc, try;
1180
1181         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1182
1183         if (chip == NULL)
1184                 return -ENODEV;
1185
1186         /* for buggy tpm, flush pcrs with extend to selected dummy */
1187         if (tpm_suspend_pcr) {
1188                 cmd.header.in = pcrextend_header;
1189                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1190                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1191                        TPM_DIGEST_SIZE);
1192                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1193                                   "extending dummy pcr before suspend");
1194         }
1195
1196         /* now do the actual savestate */
1197         for (try = 0; try < TPM_RETRY; try++) {
1198                 cmd.header.in = savestate_header;
1199                 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
1200
1201                 /*
1202                  * If the TPM indicates that it is too busy to respond to
1203                  * this command then retry before giving up.  It can take
1204                  * several seconds for this TPM to be ready.
1205                  *
1206                  * This can happen if the TPM has already been sent the
1207                  * SaveState command before the driver has loaded.  TCG 1.2
1208                  * specification states that any communication after SaveState
1209                  * may cause the TPM to invalidate previously saved state.
1210                  */
1211                 if (rc != TPM_WARN_RETRY)
1212                         break;
1213                 msleep(TPM_TIMEOUT_RETRY);
1214         }
1215
1216         if (rc)
1217                 dev_err(chip->dev,
1218                         "Error (%d) sending savestate before suspend\n", rc);
1219         else if (try > 0)
1220                 dev_warn(chip->dev, "TPM savestate took %dms\n",
1221                          try * TPM_TIMEOUT_RETRY);
1222
1223         return rc;
1224 }
1225 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1226
1227 /*
1228  * Resume from a power safe. The BIOS already restored
1229  * the TPM state.
1230  */
1231 int tpm_pm_resume(struct device *dev)
1232 {
1233         struct tpm_chip *chip = dev_get_drvdata(dev);
1234
1235         if (chip == NULL)
1236                 return -ENODEV;
1237
1238         return 0;
1239 }
1240 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1241
1242 #define TPM_GETRANDOM_RESULT_SIZE       18
1243 static struct tpm_input_header tpm_getrandom_header = {
1244         .tag = TPM_TAG_RQU_COMMAND,
1245         .length = cpu_to_be32(14),
1246         .ordinal = TPM_ORD_GET_RANDOM
1247 };
1248
1249 /**
1250  * tpm_get_random() - Get random bytes from the tpm's RNG
1251  * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1252  * @out: destination buffer for the random bytes
1253  * @max: the max number of bytes to write to @out
1254  *
1255  * Returns < 0 on error and the number of bytes read on success
1256  */
1257 int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1258 {
1259         struct tpm_chip *chip;
1260         struct tpm_cmd_t tpm_cmd;
1261         u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1262         int err, total = 0, retries = 5;
1263         u8 *dest = out;
1264
1265         chip = tpm_chip_find_get(chip_num);
1266         if (chip == NULL)
1267                 return -ENODEV;
1268
1269         if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1270                 return -EINVAL;
1271
1272         do {
1273                 tpm_cmd.header.in = tpm_getrandom_header;
1274                 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1275
1276                 err = transmit_cmd(chip, &tpm_cmd,
1277                                    TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1278                                    "attempting get random");
1279                 if (err)
1280                         break;
1281
1282                 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1283                 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1284
1285                 dest += recd;
1286                 total += recd;
1287                 num_bytes -= recd;
1288         } while (retries-- && total < max);
1289
1290         return total ? total : -EIO;
1291 }
1292 EXPORT_SYMBOL_GPL(tpm_get_random);
1293
1294 /* In case vendor provided release function, call it too.*/
1295
1296 void tpm_dev_vendor_release(struct tpm_chip *chip)
1297 {
1298         if (!chip)
1299                 return;
1300
1301         if (chip->vendor.release)
1302                 chip->vendor.release(chip->dev);
1303
1304         clear_bit(chip->dev_num, dev_mask);
1305 }
1306 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1307
1308
1309 /*
1310  * Once all references to platform device are down to 0,
1311  * release all allocated structures.
1312  */
1313 static void tpm_dev_release(struct device *dev)
1314 {
1315         struct tpm_chip *chip = dev_get_drvdata(dev);
1316
1317         if (!chip)
1318                 return;
1319
1320         tpm_dev_vendor_release(chip);
1321
1322         chip->release(dev);
1323         kfree(chip);
1324 }
1325
1326 /*
1327  * Called from tpm_<specific>.c probe function only for devices
1328  * the driver has determined it should claim.  Prior to calling
1329  * this function the specific probe function has called pci_enable_device
1330  * upon errant exit from this function specific probe function should call
1331  * pci_disable_device
1332  */
1333 struct tpm_chip *tpm_register_hardware(struct device *dev,
1334                                         const struct tpm_vendor_specific *entry)
1335 {
1336         struct tpm_chip *chip;
1337
1338         /* Driver specific per-device data */
1339         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1340
1341         if (chip == NULL)
1342                 return NULL;
1343
1344         mutex_init(&chip->tpm_mutex);
1345         INIT_LIST_HEAD(&chip->list);
1346
1347         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1348
1349         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1350
1351         if (chip->dev_num >= TPM_NUM_DEVICES) {
1352                 dev_err(dev, "No available tpm device numbers\n");
1353                 goto out_free;
1354         }
1355
1356         set_bit(chip->dev_num, dev_mask);
1357
1358         scnprintf(chip->devname, sizeof(chip->devname), "%s%d", "tpm",
1359                   chip->dev_num);
1360
1361         chip->dev = get_device(dev);
1362         chip->release = dev->release;
1363         dev->release = tpm_dev_release;
1364         dev_set_drvdata(dev, chip);
1365
1366         if (tpm_dev_add_device(chip))
1367                 goto put_device;
1368
1369         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group))
1370                 goto del_misc;
1371
1372         if (tpm_add_ppi(&dev->kobj))
1373                 goto del_misc;
1374
1375         chip->bios_dir = tpm_bios_log_setup(chip->devname);
1376
1377         /* Make chip available */
1378         spin_lock(&driver_lock);
1379         list_add_rcu(&chip->list, &tpm_chip_list);
1380         spin_unlock(&driver_lock);
1381
1382         return chip;
1383
1384 del_misc:
1385         tpm_dev_del_device(chip);
1386 put_device:
1387         put_device(chip->dev);
1388 out_free:
1389         kfree(chip);
1390         return NULL;
1391 }
1392 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1393
1394 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1395 MODULE_DESCRIPTION("TPM Driver");
1396 MODULE_VERSION("2.0");
1397 MODULE_LICENSE("GPL");