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         if (bufsiz > TPM_BUFSIZE)
 387                 bufsiz = TPM_BUFSIZE;
 388
 389         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 390         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 391         if (count == 0)
 392                 return -ENODATA;
 393         if (count > bufsiz) {
 394                 dev_err(chip->dev,
 395                         "invalid count value %x %zx \n", count, bufsiz);
 396                 return -E2BIG;
 397         }
 398
 399         mutex_lock(&chip->tpm_mutex);
 400
 401         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 402                 dev_err(chip->dev,
 403                         "tpm_transmit: tpm_send: error %zd\n", rc);
 404                 goto out;
 405         }
 406
 407         if (chip->vendor.irq)
 408                 goto out_recv;
 409
 410         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 411         do {
 412                 u8 status = chip->vendor.status(chip);
 413                 if ((status & chip->vendor.req_complete_mask) ==
 414                     chip->vendor.req_complete_val)
 415                         goto out_recv;
 416
 417                 if ((status == chip->vendor.req_canceled)) {
 418                         dev_err(chip->dev, "Operation Canceled\n");
 419                         rc = -ECANCELED;
 420                         goto out;
 421                 }
 422
 423                 msleep(TPM_TIMEOUT);    /* CHECK */
 424                 rmb();
 425         } while (time_before(jiffies, stop));
 426
 427         chip->vendor.cancel(chip);
 428         dev_err(chip->dev, "Operation Timed out\n");
 429         rc = -ETIME;
 430         goto out;
 431
 432 out_recv:
 433         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 434         if (rc < 0)
 435                 dev_err(chip->dev,
 436                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 437 out:
 438         mutex_unlock(&chip->tpm_mutex);
 439         return rc;
 440 }
 441
 442 #define TPM_DIGEST_SIZE 20
 443 #define TPM_ERROR_SIZE 10
 444 #define TPM_RET_CODE_IDX 6
 445
 446 enum tpm_capabilities {
 447         TPM_CAP_FLAG = cpu_to_be32(4),
 448         TPM_CAP_PROP = cpu_to_be32(5),
 449         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 450         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 451 };
 452
 453 enum tpm_sub_capabilities {
 454         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 455         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 456         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 457         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 458         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 459         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 460         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 461
 462 };
 463
 464 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 465                             int len, const char *desc)
 466 {
 467         int err;
 468
 469         len = tpm_transmit(chip,(u8 *) cmd, len);
 470         if (len <  0)
 471                 return len;
 472         if (len == TPM_ERROR_SIZE) {
 473                 err = be32_to_cpu(cmd->header.out.return_code);
 474                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 475                 return err;
 476         }
 477         return 0;
 478 }
 479
 480 #define TPM_INTERNAL_RESULT_SIZE 200
 481 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 482 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 483
 484 static const struct tpm_input_header tpm_getcap_header = {
 485         .tag = TPM_TAG_RQU_COMMAND,
 486         .length = cpu_to_be32(22),
 487         .ordinal = TPM_ORD_GET_CAP
 488 };
 489
 490 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 491                    const char *desc)
 492 {
 493         struct tpm_cmd_t tpm_cmd;
 494         int rc;
 495         struct tpm_chip *chip = dev_get_drvdata(dev);
 496
 497         tpm_cmd.header.in = tpm_getcap_header;
 498         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 499                 tpm_cmd.params.getcap_in.cap = subcap_id;
 500                 /*subcap field not necessary */
 501                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 502                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 503         } else {
 504                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 505                     subcap_id == TPM_CAP_FLAG_VOL)
 506                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 507                 else
 508                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 509                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 510                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 511         }
 512         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 513         if (!rc)
 514                 *cap = tpm_cmd.params.getcap_out.cap;
 515         return rc;
 516 }
 517
 518 void tpm_gen_interrupt(struct tpm_chip *chip)
 519 {
 520         struct  tpm_cmd_t tpm_cmd;
 521         ssize_t rc;
 522
 523         tpm_cmd.header.in = tpm_getcap_header;
 524         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 525         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 526         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 527
 528         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 529                         "attempting to determine the timeouts");
 530 }
 531 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 532
 533 void tpm_get_timeouts(struct tpm_chip *chip)
 534 {
 535         struct tpm_cmd_t tpm_cmd;
 536         struct timeout_t *timeout_cap;
 537         struct duration_t *duration_cap;
 538         ssize_t rc;
 539         u32 timeout;
 540         unsigned int scale = 1;
 541
 542         tpm_cmd.header.in = tpm_getcap_header;
 543         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 544         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 545         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 546
 547         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 548                         "attempting to determine the timeouts");
 549         if (rc)
 550                 goto duration;
 551
 552         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 553             be32_to_cpu(tpm_cmd.header.out.length)
 554             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 555                 return;
 556
 557         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 558         /* Don't overwrite default if value is 0 */
 559         timeout = be32_to_cpu(timeout_cap->a);
 560         if (timeout && timeout < 1000) {
 561                 /* timeouts in msec rather usec */
 562                 scale = 1000;
 563                 chip->vendor.timeout_adjusted = true;
 564         }
 565         if (timeout)
 566                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 567         timeout = be32_to_cpu(timeout_cap->b);
 568         if (timeout)
 569                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 570         timeout = be32_to_cpu(timeout_cap->c);
 571         if (timeout)
 572                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 573         timeout = be32_to_cpu(timeout_cap->d);
 574         if (timeout)
 575                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 576
 577 duration:
 578         tpm_cmd.header.in = tpm_getcap_header;
 579         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 580         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 581         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 582
 583         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 584                         "attempting to determine the durations");
 585         if (rc)
 586                 return;
 587
 588         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 589             be32_to_cpu(tpm_cmd.header.out.length)
 590             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 591                 return;
 592
 593         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 594         chip->vendor.duration[TPM_SHORT] =
 595             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 596         chip->vendor.duration[TPM_MEDIUM] =
 597             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 598         chip->vendor.duration[TPM_LONG] =
 599             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 600
 601         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 602          * value wrong and apparently reports msecs rather than usecs. So we
 603          * fix up the resulting too-small TPM_SHORT value to make things work.
 604          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 605          */
 606         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 607                 chip->vendor.duration[TPM_SHORT] = HZ;
 608                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 609                 chip->vendor.duration[TPM_LONG] *= 1000;
 610                 chip->vendor.duration_adjusted = true;
 611                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 612         }
 613 }
 614 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 615
 616 void tpm_continue_selftest(struct tpm_chip *chip)
 617 {
 618         u8 data[] = {
 619                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 620                 0, 0, 0, 10,            /* length */
 621                 0, 0, 0, 83,            /* TPM_ORD_ContinueSelfTest */
 622         };
 623
 624         tpm_transmit(chip, data, sizeof(data));
 625 }
 626 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 627
 628 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 629                         char *buf)
 630 {
 631         cap_t cap;
 632         ssize_t rc;
 633
 634         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 635                          "attempting to determine the permanent enabled state");
 636         if (rc)
 637                 return 0;
 638
 639         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 640         return rc;
 641 }
 642 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 643
 644 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 645                         char *buf)
 646 {
 647         cap_t cap;
 648         ssize_t rc;
 649
 650         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 651                          "attempting to determine the permanent active state");
 652         if (rc)
 653                 return 0;
 654
 655         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 656         return rc;
 657 }
 658 EXPORT_SYMBOL_GPL(tpm_show_active);
 659
 660 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 661                         char *buf)
 662 {
 663         cap_t cap;
 664         ssize_t rc;
 665
 666         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 667                          "attempting to determine the owner state");
 668         if (rc)
 669                 return 0;
 670
 671         rc = sprintf(buf, "%d\n", cap.owned);
 672         return rc;
 673 }
 674 EXPORT_SYMBOL_GPL(tpm_show_owned);
 675
 676 ssize_t tpm_show_temp_deactivated(struct device * dev,
 677                                 struct device_attribute * attr, char *buf)
 678 {
 679         cap_t cap;
 680         ssize_t rc;
 681
 682         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 683                          "attempting to determine the temporary state");
 684         if (rc)
 685                 return 0;
 686
 687         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 688         return rc;
 689 }
 690 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 691
 692 /*
 693  * tpm_chip_find_get - return tpm_chip for given chip number
 694  */
 695 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 696 {
 697         struct tpm_chip *pos, *chip = NULL;
 698
 699         rcu_read_lock();
 700         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 701                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 702                         continue;
 703
 704                 if (try_module_get(pos->dev->driver->owner)) {
 705                         chip = pos;
 706                         break;
 707                 }
 708         }
 709         rcu_read_unlock();
 710         return chip;
 711 }
 712
 713 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 714 #define READ_PCR_RESULT_SIZE 30
 715 static struct tpm_input_header pcrread_header = {
 716         .tag = TPM_TAG_RQU_COMMAND,
 717         .length = cpu_to_be32(14),
 718         .ordinal = TPM_ORDINAL_PCRREAD
 719 };
 720
 721 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 722 {
 723         int rc;
 724         struct tpm_cmd_t cmd;
 725
 726         cmd.header.in = pcrread_header;
 727         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 728         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 729                           "attempting to read a pcr value");
 730
 731         if (rc == 0)
 732                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 733                        TPM_DIGEST_SIZE);
 734         return rc;
 735 }
 736
 737 /**
 738  * tpm_pcr_read - read a pcr value
 739  * @chip_num:   tpm idx # or ANY
 740  * @pcr_idx:    pcr idx to retrieve
 741  * @res_buf:    TPM_PCR value
 742  *              size of res_buf is 20 bytes (or NULL if you don't care)
 743  *
 744  * The TPM driver should be built-in, but for whatever reason it
 745  * isn't, protect against the chip disappearing, by incrementing
 746  * the module usage count.
 747  */
 748 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 749 {
 750         struct tpm_chip *chip;
 751         int rc;
 752
 753         chip = tpm_chip_find_get(chip_num);
 754         if (chip == NULL)
 755                 return -ENODEV;
 756         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 757         tpm_chip_put(chip);
 758         return rc;
 759 }
 760 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 761
 762 /**
 763  * tpm_pcr_extend - extend pcr value with hash
 764  * @chip_num:   tpm idx # or AN&
 765  * @pcr_idx:    pcr idx to extend
 766  * @hash:       hash value used to extend pcr value
 767  *
 768  * The TPM driver should be built-in, but for whatever reason it
 769  * isn't, protect against the chip disappearing, by incrementing
 770  * the module usage count.
 771  */
 772 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 773 #define EXTEND_PCR_RESULT_SIZE 34
 774 static struct tpm_input_header pcrextend_header = {
 775         .tag = TPM_TAG_RQU_COMMAND,
 776         .length = cpu_to_be32(34),
 777         .ordinal = TPM_ORD_PCR_EXTEND
 778 };
 779
 780 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 781 {
 782         struct tpm_cmd_t cmd;
 783         int rc;
 784         struct tpm_chip *chip;
 785
 786         chip = tpm_chip_find_get(chip_num);
 787         if (chip == NULL)
 788                 return -ENODEV;
 789
 790         cmd.header.in = pcrextend_header;
 791         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 792         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 793         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 794                           "attempting extend a PCR value");
 795
 796         tpm_chip_put(chip);
 797         return rc;
 798 }
 799 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 800
 801 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 802 {
 803         struct tpm_chip *chip;
 804         int rc;
 805
 806         chip = tpm_chip_find_get(chip_num);
 807         if (chip == NULL)
 808                 return -ENODEV;
 809
 810         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 811
 812         tpm_chip_put(chip);
 813         return rc;
 814 }
 815 EXPORT_SYMBOL_GPL(tpm_send);
 816
 817 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 818                       char *buf)
 819 {
 820         cap_t cap;
 821         u8 digest[TPM_DIGEST_SIZE];
 822         ssize_t rc;
 823         int i, j, num_pcrs;
 824         char *str = buf;
 825         struct tpm_chip *chip = dev_get_drvdata(dev);
 826
 827         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 828                         "attempting to determine the number of PCRS");
 829         if (rc)
 830                 return 0;
 831
 832         num_pcrs = be32_to_cpu(cap.num_pcrs);
 833         for (i = 0; i < num_pcrs; i++) {
 834                 rc = __tpm_pcr_read(chip, i, digest);
 835                 if (rc)
 836                         break;
 837                 str += sprintf(str, "PCR-%02d: ", i);
 838                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 839                         str += sprintf(str, "%02X ", digest[j]);
 840                 str += sprintf(str, "\n");
 841         }
 842         return str - buf;
 843 }
 844 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 845
 846 #define  READ_PUBEK_RESULT_SIZE 314
 847 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 848 struct tpm_input_header tpm_readpubek_header = {
 849         .tag = TPM_TAG_RQU_COMMAND,
 850         .length = cpu_to_be32(30),
 851         .ordinal = TPM_ORD_READPUBEK
 852 };
 853
 854 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 855                        char *buf)
 856 {
 857         u8 *data;
 858         struct tpm_cmd_t tpm_cmd;
 859         ssize_t err;
 860         int i, rc;
 861         char *str = buf;
 862
 863         struct tpm_chip *chip = dev_get_drvdata(dev);
 864
 865         tpm_cmd.header.in = tpm_readpubek_header;
 866         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 867                         "attempting to read the PUBEK");
 868         if (err)
 869                 goto out;
 870
 871         /*
 872            ignore header 10 bytes
 873            algorithm 32 bits (1 == RSA )
 874            encscheme 16 bits
 875            sigscheme 16 bits
 876            parameters (RSA 12->bytes: keybit, #primes, expbit)
 877            keylenbytes 32 bits
 878            256 byte modulus
 879            ignore checksum 20 bytes
 880          */
 881         data = tpm_cmd.params.readpubek_out_buffer;
 882         str +=
 883             sprintf(str,
 884                     "Algorithm: %02X %02X %02X %02X\n"
 885                     "Encscheme: %02X %02X\n"
 886                     "Sigscheme: %02X %02X\n"
 887                     "Parameters: %02X %02X %02X %02X "
 888                     "%02X %02X %02X %02X "
 889                     "%02X %02X %02X %02X\n"
 890                     "Modulus length: %d\n"
 891                     "Modulus:\n",
 892                     data[0], data[1], data[2], data[3],
 893                     data[4], data[5],
 894                     data[6], data[7],
 895                     data[12], data[13], data[14], data[15],
 896                     data[16], data[17], data[18], data[19],
 897                     data[20], data[21], data[22], data[23],
 898                     be32_to_cpu(*((__be32 *) (data + 24))));
 899
 900         for (i = 0; i < 256; i++) {
 901                 str += sprintf(str, "%02X ", data[i + 28]);
 902                 if ((i + 1) % 16 == 0)
 903                         str += sprintf(str, "\n");
 904         }
 905 out:
 906         rc = str - buf;
 907         return rc;
 908 }
 909 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 910
 911
 912 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 913                       char *buf)
 914 {
 915         cap_t cap;
 916         ssize_t rc;
 917         char *str = buf;
 918
 919         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 920                         "attempting to determine the manufacturer");
 921         if (rc)
 922                 return 0;
 923         str += sprintf(str, "Manufacturer: 0x%x\n",
 924                        be32_to_cpu(cap.manufacturer_id));
 925
 926         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
 927                         "attempting to determine the 1.1 version");
 928         if (rc)
 929                 return 0;
 930         str += sprintf(str,
 931                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 932                        cap.tpm_version.Major, cap.tpm_version.Minor,
 933                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
 934         return str - buf;
 935 }
 936 EXPORT_SYMBOL_GPL(tpm_show_caps);
 937
 938 ssize_t tpm_show_caps_1_2(struct device * dev,
 939                           struct device_attribute * attr, char *buf)
 940 {
 941         cap_t cap;
 942         ssize_t rc;
 943         char *str = buf;
 944
 945         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 946                         "attempting to determine the manufacturer");
 947         if (rc)
 948                 return 0;
 949         str += sprintf(str, "Manufacturer: 0x%x\n",
 950                        be32_to_cpu(cap.manufacturer_id));
 951         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
 952                          "attempting to determine the 1.2 version");
 953         if (rc)
 954                 return 0;
 955         str += sprintf(str,
 956                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 957                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
 958                        cap.tpm_version_1_2.revMajor,
 959                        cap.tpm_version_1_2.revMinor);
 960         return str - buf;
 961 }
 962 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 963
 964 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
 965                           char *buf)
 966 {
 967         struct tpm_chip *chip = dev_get_drvdata(dev);
 968
 969         if (chip->vendor.duration[TPM_LONG] == 0)
 970                 return 0;
 971
 972         return sprintf(buf, "%d %d %d [%s]\n",
 973                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
 974                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
 975                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
 976                        chip->vendor.duration_adjusted
 977                        ? "adjusted" : "original");
 978 }
 979 EXPORT_SYMBOL_GPL(tpm_show_durations);
 980
 981 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
 982                           char *buf)
 983 {
 984         struct tpm_chip *chip = dev_get_drvdata(dev);
 985
 986         return sprintf(buf, "%d %d %d %d [%s]\n",
 987                        jiffies_to_usecs(chip->vendor.timeout_a),
 988                        jiffies_to_usecs(chip->vendor.timeout_b),
 989                        jiffies_to_usecs(chip->vendor.timeout_c),
 990                        jiffies_to_usecs(chip->vendor.timeout_d),
 991                        chip->vendor.timeout_adjusted
 992                        ? "adjusted" : "original");
 993 }
 994 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
 995
 996 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 997                         const char *buf, size_t count)
 998 {
 999         struct tpm_chip *chip = dev_get_drvdata(dev);
1000         if (chip == NULL)
1001                 return 0;
1002
1003         chip->vendor.cancel(chip);
1004         return count;
1005 }
1006 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1007
1008 /*
1009  * Device file system interface to the TPM
1010  *
1011  * It's assured that the chip will be opened just once,
1012  * by the check of is_open variable, which is protected
1013  * by driver_lock.
1014  */
1015 int tpm_open(struct inode *inode, struct file *file)
1016 {
1017         int minor = iminor(inode);
1018         struct tpm_chip *chip = NULL, *pos;
1019
1020         rcu_read_lock();
1021         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1022                 if (pos->vendor.miscdev.minor == minor) {
1023                         chip = pos;
1024                         get_device(chip->dev);
1025                         break;
1026                 }
1027         }
1028         rcu_read_unlock();
1029
1030         if (!chip)
1031                 return -ENODEV;
1032
1033         if (test_and_set_bit(0, &chip->is_open)) {
1034                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1035                 put_device(chip->dev);
1036                 return -EBUSY;
1037         }
1038
1039         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1040         if (chip->data_buffer == NULL) {
1041                 clear_bit(0, &chip->is_open);
1042                 put_device(chip->dev);
1043                 return -ENOMEM;
1044         }
1045
1046         atomic_set(&chip->data_pending, 0);
1047
1048         file->private_data = chip;
1049         return 0;
1050 }
1051 EXPORT_SYMBOL_GPL(tpm_open);
1052
1053 /*
1054  * Called on file close
1055  */
1056 int tpm_release(struct inode *inode, struct file *file)
1057 {
1058         struct tpm_chip *chip = file->private_data;
1059
1060         del_singleshot_timer_sync(&chip->user_read_timer);
1061         flush_work_sync(&chip->work);
1062         file->private_data = NULL;
1063         atomic_set(&chip->data_pending, 0);
1064         kfree(chip->data_buffer);
1065         clear_bit(0, &chip->is_open);
1066         put_device(chip->dev);
1067         return 0;
1068 }
1069 EXPORT_SYMBOL_GPL(tpm_release);
1070
1071 ssize_t tpm_write(struct file *file, const char __user *buf,
1072                   size_t size, loff_t *off)
1073 {
1074         struct tpm_chip *chip = file->private_data;
1075         size_t in_size = size, out_size;
1076
1077         /* cannot perform a write until the read has cleared
1078            either via tpm_read or a user_read_timer timeout */
1079         while (atomic_read(&chip->data_pending) != 0)
1080                 msleep(TPM_TIMEOUT);
1081
1082         mutex_lock(&chip->buffer_mutex);
1083
1084         if (in_size > TPM_BUFSIZE)
1085                 in_size = TPM_BUFSIZE;
1086
1087         if (copy_from_user
1088             (chip->data_buffer, (void __user *) buf, in_size)) {
1089                 mutex_unlock(&chip->buffer_mutex);
1090                 return -EFAULT;
1091         }
1092
1093         /* atomic tpm command send and result receive */
1094         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1095
1096         atomic_set(&chip->data_pending, out_size);
1097         mutex_unlock(&chip->buffer_mutex);
1098
1099         /* Set a timeout by which the reader must come claim the result */
1100         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1101
1102         return in_size;
1103 }
1104 EXPORT_SYMBOL_GPL(tpm_write);
1105
1106 ssize_t tpm_read(struct file *file, char __user *buf,
1107                  size_t size, loff_t *off)
1108 {
1109         struct tpm_chip *chip = file->private_data;
1110         ssize_t ret_size;
1111         int rc;
1112
1113         del_singleshot_timer_sync(&chip->user_read_timer);
1114         flush_work_sync(&chip->work);
1115         ret_size = atomic_read(&chip->data_pending);
1116         atomic_set(&chip->data_pending, 0);
1117         if (ret_size > 0) {     /* relay data */
1118                 if (size < ret_size)
1119                         ret_size = size;
1120
1121                 mutex_lock(&chip->buffer_mutex);
1122                 rc = copy_to_user(buf, chip->data_buffer, ret_size);
1123                 memset(chip->data_buffer, 0, ret_size);
1124                 if (rc)
1125                         ret_size = -EFAULT;
1126
1127                 mutex_unlock(&chip->buffer_mutex);
1128         }
1129
1130         return ret_size;
1131 }
1132 EXPORT_SYMBOL_GPL(tpm_read);
1133
1134 void tpm_remove_hardware(struct device *dev)
1135 {
1136         struct tpm_chip *chip = dev_get_drvdata(dev);
1137
1138         if (chip == NULL) {
1139                 dev_err(dev, "No device data found\n");
1140                 return;
1141         }
1142
1143         spin_lock(&driver_lock);
1144         list_del_rcu(&chip->list);
1145         spin_unlock(&driver_lock);
1146         synchronize_rcu();
1147
1148         misc_deregister(&chip->vendor.miscdev);
1149         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1150         tpm_bios_log_teardown(chip->bios_dir);
1151
1152         /* write it this way to be explicit (chip->dev == dev) */
1153         put_device(chip->dev);
1154 }
1155 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1156
1157 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1158 #define SAVESTATE_RESULT_SIZE 10
1159
1160 static struct tpm_input_header savestate_header = {
1161         .tag = TPM_TAG_RQU_COMMAND,
1162         .length = cpu_to_be32(10),
1163         .ordinal = TPM_ORD_SAVESTATE
1164 };
1165
1166 /*
1167  * We are about to suspend. Save the TPM state
1168  * so that it can be restored.
1169  */
1170 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1171 {
1172         struct tpm_chip *chip = dev_get_drvdata(dev);
1173         struct tpm_cmd_t cmd;
1174         int rc;
1175
1176         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1177
1178         if (chip == NULL)
1179                 return -ENODEV;
1180
1181         /* for buggy tpm, flush pcrs with extend to selected dummy */
1182         if (tpm_suspend_pcr) {
1183                 cmd.header.in = pcrextend_header;
1184                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1185                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1186                        TPM_DIGEST_SIZE);
1187                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1188                                   "extending dummy pcr before suspend");
1189         }
1190
1191         /* now do the actual savestate */
1192         cmd.header.in = savestate_header;
1193         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1194                           "sending savestate before suspend");
1195         return rc;
1196 }
1197 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1198
1199 /*
1200  * Resume from a power safe. The BIOS already restored
1201  * the TPM state.
1202  */
1203 int tpm_pm_resume(struct device *dev)
1204 {
1205         struct tpm_chip *chip = dev_get_drvdata(dev);
1206
1207         if (chip == NULL)
1208                 return -ENODEV;
1209
1210         return 0;
1211 }
1212 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1213
1214 /* In case vendor provided release function, call it too.*/
1215
1216 void tpm_dev_vendor_release(struct tpm_chip *chip)
1217 {
1218         if (chip->vendor.release)
1219                 chip->vendor.release(chip->dev);
1220
1221         clear_bit(chip->dev_num, dev_mask);
1222         kfree(chip->vendor.miscdev.name);
1223 }
1224 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1225
1226
1227 /*
1228  * Once all references to platform device are down to 0,
1229  * release all allocated structures.
1230  */
1231 void tpm_dev_release(struct device *dev)
1232 {
1233         struct tpm_chip *chip = dev_get_drvdata(dev);
1234
1235         tpm_dev_vendor_release(chip);
1236
1237         chip->release(dev);
1238         kfree(chip);
1239 }
1240 EXPORT_SYMBOL_GPL(tpm_dev_release);
1241
1242 /*
1243  * Called from tpm_<specific>.c probe function only for devices
1244  * the driver has determined it should claim.  Prior to calling
1245  * this function the specific probe function has called pci_enable_device
1246  * upon errant exit from this function specific probe function should call
1247  * pci_disable_device
1248  */
1249 struct tpm_chip *tpm_register_hardware(struct device *dev,
1250                                         const struct tpm_vendor_specific *entry)
1251 {
1252 #define DEVNAME_SIZE 7
1253
1254         char *devname;
1255         struct tpm_chip *chip;
1256
1257         /* Driver specific per-device data */
1258         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1259         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1260
1261         if (chip == NULL || devname == NULL)
1262                 goto out_free;
1263
1264         mutex_init(&chip->buffer_mutex);
1265         mutex_init(&chip->tpm_mutex);
1266         INIT_LIST_HEAD(&chip->list);
1267
1268         INIT_WORK(&chip->work, timeout_work);
1269
1270         setup_timer(&chip->user_read_timer, user_reader_timeout,
1271                         (unsigned long)chip);
1272
1273         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1274
1275         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1276
1277         if (chip->dev_num >= TPM_NUM_DEVICES) {
1278                 dev_err(dev, "No available tpm device numbers\n");
1279                 goto out_free;
1280         } else if (chip->dev_num == 0)
1281                 chip->vendor.miscdev.minor = TPM_MINOR;
1282         else
1283                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1284
1285         set_bit(chip->dev_num, dev_mask);
1286
1287         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1288         chip->vendor.miscdev.name = devname;
1289
1290         chip->vendor.miscdev.parent = dev;
1291         chip->dev = get_device(dev);
1292         chip->release = dev->release;
1293         dev->release = tpm_dev_release;
1294         dev_set_drvdata(dev, chip);
1295
1296         if (misc_register(&chip->vendor.miscdev)) {
1297                 dev_err(chip->dev,
1298                         "unable to misc_register %s, minor %d\n",
1299                         chip->vendor.miscdev.name,
1300                         chip->vendor.miscdev.minor);
1301                 put_device(chip->dev);
1302                 return NULL;
1303         }
1304
1305         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1306                 misc_deregister(&chip->vendor.miscdev);
1307                 put_device(chip->dev);
1308
1309                 return NULL;
1310         }
1311
1312         chip->bios_dir = tpm_bios_log_setup(devname);
1313
1314         /* Make chip available */
1315         spin_lock(&driver_lock);
1316         list_add_rcu(&chip->list, &tpm_chip_list);
1317         spin_unlock(&driver_lock);
1318
1319         return chip;
1320
1321 out_free:
1322         kfree(chip);
1323         kfree(devname);
1324         return NULL;
1325 }
1326 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1327
1328 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1329 MODULE_DESCRIPTION("TPM Driver");
1330 MODULE_VERSION("2.0");
1331 MODULE_LICENSE("GPL");