drivers/char/tpm/tpm.c

   1 /*
   2  * Copyright (C) 2004 IBM Corporation
   3  *
   4  * Authors:
   5  * Leendert van Doorn <leendert@watson.ibm.com>
   6  * Dave Safford <safford@watson.ibm.com>
   7  * Reiner Sailer <sailer@watson.ibm.com>
   8  * Kylene Hall <kjhall@us.ibm.com>
   9  *
  10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  11  *
  12  * Device driver for TCG/TCPA TPM (trusted platform module).
  13  * Specifications at www.trustedcomputinggroup.org
  14  *
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License as
  17  * published by the Free Software Foundation, version 2 of the
  18  * License.
  19  *
  20  * Note, the TPM chip is not interrupt driven (only polling)
  21  * and can have very long timeouts (minutes!). Hence the unusual
  22  * calls to msleep.
  23  *
  24  */
  25
  26 #include <linux/poll.h>
  27 #include <linux/slab.h>
  28 #include <linux/mutex.h>
  29 #include <linux/spinlock.h>
  30
  31 #include "tpm.h"
  32
  33 enum tpm_const {
  34         TPM_MINOR = 224,        /* officially assigned */
  35         TPM_BUFSIZE = 4096,
  36         TPM_NUM_DEVICES = 256,
  37 };
  38
  39 enum tpm_duration {
  40         TPM_SHORT = 0,
  41         TPM_MEDIUM = 1,
  42         TPM_LONG = 2,
  43         TPM_UNDEFINED,
  44 };
  45
  46 #define TPM_MAX_ORDINAL 243
  47 #define TPM_MAX_PROTECTED_ORDINAL 12
  48 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
  49
  50 /*
  51  * Bug workaround - some TPM's don't flush the most
  52  * recently changed pcr on suspend, so force the flush
  53  * with an extend to the selected _unused_ non-volatile pcr.
  54  */
  55 static int tpm_suspend_pcr;
  56 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
  57 MODULE_PARM_DESC(suspend_pcr,
  58                  "PCR to use for dummy writes to faciltate flush on suspend.");
  59
  60 static LIST_HEAD(tpm_chip_list);
  61 static DEFINE_SPINLOCK(driver_lock);
  62 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
  63
  64 /*
  65  * Array with one entry per ordinal defining the maximum amount
  66  * of time the chip could take to return the result.  The ordinal
  67  * designation of short, medium or long is defined in a table in
  68  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
  69  * values of the SHORT, MEDIUM, and LONG durations are retrieved
  70  * from the chip during initialization with a call to tpm_get_timeouts.
  71  */
  72 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
  73         TPM_UNDEFINED,          /* 0 */
  74         TPM_UNDEFINED,
  75         TPM_UNDEFINED,
  76         TPM_UNDEFINED,
  77         TPM_UNDEFINED,
  78         TPM_UNDEFINED,          /* 5 */
  79         TPM_UNDEFINED,
  80         TPM_UNDEFINED,
  81         TPM_UNDEFINED,
  82         TPM_UNDEFINED,
  83         TPM_SHORT,              /* 10 */
  84         TPM_SHORT,
  85 };
  86
  87 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
  88         TPM_UNDEFINED,          /* 0 */
  89         TPM_UNDEFINED,
  90         TPM_UNDEFINED,
  91         TPM_UNDEFINED,
  92         TPM_UNDEFINED,
  93         TPM_UNDEFINED,          /* 5 */
  94         TPM_UNDEFINED,
  95         TPM_UNDEFINED,
  96         TPM_UNDEFINED,
  97         TPM_UNDEFINED,
  98         TPM_SHORT,              /* 10 */
  99         TPM_SHORT,
 100         TPM_MEDIUM,
 101         TPM_LONG,
 102         TPM_LONG,
 103         TPM_MEDIUM,             /* 15 */
 104         TPM_SHORT,
 105         TPM_SHORT,
 106         TPM_MEDIUM,
 107         TPM_LONG,
 108         TPM_SHORT,              /* 20 */
 109         TPM_SHORT,
 110         TPM_MEDIUM,
 111         TPM_MEDIUM,
 112         TPM_MEDIUM,
 113         TPM_SHORT,              /* 25 */
 114         TPM_SHORT,
 115         TPM_MEDIUM,
 116         TPM_SHORT,
 117         TPM_SHORT,
 118         TPM_MEDIUM,             /* 30 */
 119         TPM_LONG,
 120         TPM_MEDIUM,
 121         TPM_SHORT,
 122         TPM_SHORT,
 123         TPM_SHORT,              /* 35 */
 124         TPM_MEDIUM,
 125         TPM_MEDIUM,
 126         TPM_UNDEFINED,
 127         TPM_UNDEFINED,
 128         TPM_MEDIUM,             /* 40 */
 129         TPM_LONG,
 130         TPM_MEDIUM,
 131         TPM_SHORT,
 132         TPM_SHORT,
 133         TPM_SHORT,              /* 45 */
 134         TPM_SHORT,
 135         TPM_SHORT,
 136         TPM_SHORT,
 137         TPM_LONG,
 138         TPM_MEDIUM,             /* 50 */
 139         TPM_MEDIUM,
 140         TPM_UNDEFINED,
 141         TPM_UNDEFINED,
 142         TPM_UNDEFINED,
 143         TPM_UNDEFINED,          /* 55 */
 144         TPM_UNDEFINED,
 145         TPM_UNDEFINED,
 146         TPM_UNDEFINED,
 147         TPM_UNDEFINED,
 148         TPM_MEDIUM,             /* 60 */
 149         TPM_MEDIUM,
 150         TPM_MEDIUM,
 151         TPM_SHORT,
 152         TPM_SHORT,
 153         TPM_MEDIUM,             /* 65 */
 154         TPM_UNDEFINED,
 155         TPM_UNDEFINED,
 156         TPM_UNDEFINED,
 157         TPM_UNDEFINED,
 158         TPM_SHORT,              /* 70 */
 159         TPM_SHORT,
 160         TPM_UNDEFINED,
 161         TPM_UNDEFINED,
 162         TPM_UNDEFINED,
 163         TPM_UNDEFINED,          /* 75 */
 164         TPM_UNDEFINED,
 165         TPM_UNDEFINED,
 166         TPM_UNDEFINED,
 167         TPM_UNDEFINED,
 168         TPM_LONG,               /* 80 */
 169         TPM_UNDEFINED,
 170         TPM_MEDIUM,
 171         TPM_LONG,
 172         TPM_SHORT,
 173         TPM_UNDEFINED,          /* 85 */
 174         TPM_UNDEFINED,
 175         TPM_UNDEFINED,
 176         TPM_UNDEFINED,
 177         TPM_UNDEFINED,
 178         TPM_SHORT,              /* 90 */
 179         TPM_SHORT,
 180         TPM_SHORT,
 181         TPM_SHORT,
 182         TPM_SHORT,
 183         TPM_UNDEFINED,          /* 95 */
 184         TPM_UNDEFINED,
 185         TPM_UNDEFINED,
 186         TPM_UNDEFINED,
 187         TPM_UNDEFINED,
 188         TPM_MEDIUM,             /* 100 */
 189         TPM_SHORT,
 190         TPM_SHORT,
 191         TPM_UNDEFINED,
 192         TPM_UNDEFINED,
 193         TPM_UNDEFINED,          /* 105 */
 194         TPM_UNDEFINED,
 195         TPM_UNDEFINED,
 196         TPM_UNDEFINED,
 197         TPM_UNDEFINED,
 198         TPM_SHORT,              /* 110 */
 199         TPM_SHORT,
 200         TPM_SHORT,
 201         TPM_SHORT,
 202         TPM_SHORT,
 203         TPM_SHORT,              /* 115 */
 204         TPM_SHORT,
 205         TPM_SHORT,
 206         TPM_UNDEFINED,
 207         TPM_UNDEFINED,
 208         TPM_LONG,               /* 120 */
 209         TPM_LONG,
 210         TPM_MEDIUM,
 211         TPM_UNDEFINED,
 212         TPM_SHORT,
 213         TPM_SHORT,              /* 125 */
 214         TPM_SHORT,
 215         TPM_LONG,
 216         TPM_SHORT,
 217         TPM_SHORT,
 218         TPM_SHORT,              /* 130 */
 219         TPM_MEDIUM,
 220         TPM_UNDEFINED,
 221         TPM_SHORT,
 222         TPM_MEDIUM,
 223         TPM_UNDEFINED,          /* 135 */
 224         TPM_UNDEFINED,
 225         TPM_UNDEFINED,
 226         TPM_UNDEFINED,
 227         TPM_UNDEFINED,
 228         TPM_SHORT,              /* 140 */
 229         TPM_SHORT,
 230         TPM_UNDEFINED,
 231         TPM_UNDEFINED,
 232         TPM_UNDEFINED,
 233         TPM_UNDEFINED,          /* 145 */
 234         TPM_UNDEFINED,
 235         TPM_UNDEFINED,
 236         TPM_UNDEFINED,
 237         TPM_UNDEFINED,
 238         TPM_SHORT,              /* 150 */
 239         TPM_MEDIUM,
 240         TPM_MEDIUM,
 241         TPM_SHORT,
 242         TPM_SHORT,
 243         TPM_UNDEFINED,          /* 155 */
 244         TPM_UNDEFINED,
 245         TPM_UNDEFINED,
 246         TPM_UNDEFINED,
 247         TPM_UNDEFINED,
 248         TPM_SHORT,              /* 160 */
 249         TPM_SHORT,
 250         TPM_SHORT,
 251         TPM_SHORT,
 252         TPM_UNDEFINED,
 253         TPM_UNDEFINED,          /* 165 */
 254         TPM_UNDEFINED,
 255         TPM_UNDEFINED,
 256         TPM_UNDEFINED,
 257         TPM_UNDEFINED,
 258         TPM_LONG,               /* 170 */
 259         TPM_UNDEFINED,
 260         TPM_UNDEFINED,
 261         TPM_UNDEFINED,
 262         TPM_UNDEFINED,
 263         TPM_UNDEFINED,          /* 175 */
 264         TPM_UNDEFINED,
 265         TPM_UNDEFINED,
 266         TPM_UNDEFINED,
 267         TPM_UNDEFINED,
 268         TPM_MEDIUM,             /* 180 */
 269         TPM_SHORT,
 270         TPM_MEDIUM,
 271         TPM_MEDIUM,
 272         TPM_MEDIUM,
 273         TPM_MEDIUM,             /* 185 */
 274         TPM_SHORT,
 275         TPM_UNDEFINED,
 276         TPM_UNDEFINED,
 277         TPM_UNDEFINED,
 278         TPM_UNDEFINED,          /* 190 */
 279         TPM_UNDEFINED,
 280         TPM_UNDEFINED,
 281         TPM_UNDEFINED,
 282         TPM_UNDEFINED,
 283         TPM_UNDEFINED,          /* 195 */
 284         TPM_UNDEFINED,
 285         TPM_UNDEFINED,
 286         TPM_UNDEFINED,
 287         TPM_UNDEFINED,
 288         TPM_SHORT,              /* 200 */
 289         TPM_UNDEFINED,
 290         TPM_UNDEFINED,
 291         TPM_UNDEFINED,
 292         TPM_SHORT,
 293         TPM_SHORT,              /* 205 */
 294         TPM_SHORT,
 295         TPM_SHORT,
 296         TPM_SHORT,
 297         TPM_SHORT,
 298         TPM_MEDIUM,             /* 210 */
 299         TPM_UNDEFINED,
 300         TPM_MEDIUM,
 301         TPM_MEDIUM,
 302         TPM_MEDIUM,
 303         TPM_UNDEFINED,          /* 215 */
 304         TPM_MEDIUM,
 305         TPM_UNDEFINED,
 306         TPM_UNDEFINED,
 307         TPM_SHORT,
 308         TPM_SHORT,              /* 220 */
 309         TPM_SHORT,
 310         TPM_SHORT,
 311         TPM_SHORT,
 312         TPM_SHORT,
 313         TPM_UNDEFINED,          /* 225 */
 314         TPM_UNDEFINED,
 315         TPM_UNDEFINED,
 316         TPM_UNDEFINED,
 317         TPM_UNDEFINED,
 318         TPM_SHORT,              /* 230 */
 319         TPM_LONG,
 320         TPM_MEDIUM,
 321         TPM_UNDEFINED,
 322         TPM_UNDEFINED,
 323         TPM_UNDEFINED,          /* 235 */
 324         TPM_UNDEFINED,
 325         TPM_UNDEFINED,
 326         TPM_UNDEFINED,
 327         TPM_UNDEFINED,
 328         TPM_SHORT,              /* 240 */
 329         TPM_UNDEFINED,
 330         TPM_MEDIUM,
 331 };
 332
 333 static void user_reader_timeout(unsigned long ptr)
 334 {
 335         struct tpm_chip *chip = (struct tpm_chip *) ptr;
 336
 337         schedule_work(&chip->work);
 338 }
 339
 340 static void timeout_work(struct work_struct *work)
 341 {
 342         struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
 343
 344         mutex_lock(&chip->buffer_mutex);
 345         atomic_set(&chip->data_pending, 0);
 346         memset(chip->data_buffer, 0, TPM_BUFSIZE);
 347         mutex_unlock(&chip->buffer_mutex);
 348 }
 349
 350 /*
 351  * Returns max number of jiffies to wait
 352  */
 353 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
 354                                            u32 ordinal)
 355 {
 356         int duration_idx = TPM_UNDEFINED;
 357         int duration = 0;
 358
 359         if (ordinal < TPM_MAX_ORDINAL)
 360                 duration_idx = tpm_ordinal_duration[ordinal];
 361         else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
 362                  TPM_MAX_PROTECTED_ORDINAL)
 363                 duration_idx =
 364                     tpm_protected_ordinal_duration[ordinal &
 365                                                    TPM_PROTECTED_ORDINAL_MASK];
 366
 367         if (duration_idx != TPM_UNDEFINED)
 368                 duration = chip->vendor.duration[duration_idx];
 369         if (duration <= 0)
 370                 return 2 * 60 * HZ;
 371         else
 372                 return duration;
 373 }
 374 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
 375
 376 /*
 377  * Internal kernel interface to transmit TPM commands
 378  */
 379 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 380                             size_t bufsiz)
 381 {
 382         ssize_t rc;
 383         u32 count, ordinal;
 384         unsigned long stop;
 385
 386         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 387         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 388         if (count == 0)
 389                 return -ENODATA;
 390         if (count > bufsiz) {
 391                 dev_err(chip->dev,
 392                         "invalid count value %x %zx \n", count, bufsiz);
 393                 return -E2BIG;
 394         }
 395
 396         mutex_lock(&chip->tpm_mutex);
 397
 398         if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
 399                 dev_err(chip->dev,
 400                         "tpm_transmit: tpm_send: error %zd\n", rc);
 401                 goto out;
 402         }
 403
 404         if (chip->vendor.irq)
 405                 goto out_recv;
 406
 407         stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
 408         do {
 409                 u8 status = chip->vendor.status(chip);
 410                 if ((status & chip->vendor.req_complete_mask) ==
 411                     chip->vendor.req_complete_val)
 412                         goto out_recv;
 413
 414                 if ((status == chip->vendor.req_canceled)) {
 415                         dev_err(chip->dev, "Operation Canceled\n");
 416                         rc = -ECANCELED;
 417                         goto out;
 418                 }
 419
 420                 msleep(TPM_TIMEOUT);    /* CHECK */
 421                 rmb();
 422         } while (time_before(jiffies, stop));
 423
 424         chip->vendor.cancel(chip);
 425         dev_err(chip->dev, "Operation Timed out\n");
 426         rc = -ETIME;
 427         goto out;
 428
 429 out_recv:
 430         rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
 431         if (rc < 0)
 432                 dev_err(chip->dev,
 433                         "tpm_transmit: tpm_recv: error %zd\n", rc);
 434 out:
 435         mutex_unlock(&chip->tpm_mutex);
 436         return rc;
 437 }
 438
 439 #define TPM_DIGEST_SIZE 20
 440 #define TPM_ERROR_SIZE 10
 441 #define TPM_RET_CODE_IDX 6
 442
 443 enum tpm_capabilities {
 444         TPM_CAP_FLAG = cpu_to_be32(4),
 445         TPM_CAP_PROP = cpu_to_be32(5),
 446         CAP_VERSION_1_1 = cpu_to_be32(0x06),
 447         CAP_VERSION_1_2 = cpu_to_be32(0x1A)
 448 };
 449
 450 enum tpm_sub_capabilities {
 451         TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
 452         TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
 453         TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
 454         TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
 455         TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
 456         TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
 457         TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
 458
 459 };
 460
 461 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
 462                             int len, const char *desc)
 463 {
 464         int err;
 465
 466         len = tpm_transmit(chip,(u8 *) cmd, len);
 467         if (len <  0)
 468                 return len;
 469         if (len == TPM_ERROR_SIZE) {
 470                 err = be32_to_cpu(cmd->header.out.return_code);
 471                 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
 472                 return err;
 473         }
 474         return 0;
 475 }
 476
 477 #define TPM_INTERNAL_RESULT_SIZE 200
 478 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
 479 #define TPM_ORD_GET_CAP cpu_to_be32(101)
 480
 481 static const struct tpm_input_header tpm_getcap_header = {
 482         .tag = TPM_TAG_RQU_COMMAND,
 483         .length = cpu_to_be32(22),
 484         .ordinal = TPM_ORD_GET_CAP
 485 };
 486
 487 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
 488                    const char *desc)
 489 {
 490         struct tpm_cmd_t tpm_cmd;
 491         int rc;
 492         struct tpm_chip *chip = dev_get_drvdata(dev);
 493
 494         tpm_cmd.header.in = tpm_getcap_header;
 495         if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
 496                 tpm_cmd.params.getcap_in.cap = subcap_id;
 497                 /*subcap field not necessary */
 498                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
 499                 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
 500         } else {
 501                 if (subcap_id == TPM_CAP_FLAG_PERM ||
 502                     subcap_id == TPM_CAP_FLAG_VOL)
 503                         tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
 504                 else
 505                         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 506                 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 507                 tpm_cmd.params.getcap_in.subcap = subcap_id;
 508         }
 509         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
 510         if (!rc)
 511                 *cap = tpm_cmd.params.getcap_out.cap;
 512         return rc;
 513 }
 514
 515 void tpm_gen_interrupt(struct tpm_chip *chip)
 516 {
 517         struct  tpm_cmd_t tpm_cmd;
 518         ssize_t rc;
 519
 520         tpm_cmd.header.in = tpm_getcap_header;
 521         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 522         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 523         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 524
 525         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 526                         "attempting to determine the timeouts");
 527 }
 528 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
 529
 530 void tpm_get_timeouts(struct tpm_chip *chip)
 531 {
 532         struct tpm_cmd_t tpm_cmd;
 533         struct timeout_t *timeout_cap;
 534         struct duration_t *duration_cap;
 535         ssize_t rc;
 536         u32 timeout;
 537         unsigned int scale = 1;
 538
 539         tpm_cmd.header.in = tpm_getcap_header;
 540         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 541         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 542         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
 543
 544         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 545                         "attempting to determine the timeouts");
 546         if (rc)
 547                 goto duration;
 548
 549         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 550             be32_to_cpu(tpm_cmd.header.out.length)
 551             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
 552                 return;
 553
 554         timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
 555         /* Don't overwrite default if value is 0 */
 556         timeout = be32_to_cpu(timeout_cap->a);
 557         if (timeout && timeout < 1000) {
 558                 /* timeouts in msec rather usec */
 559                 scale = 1000;
 560                 chip->vendor.timeout_adjusted = true;
 561         }
 562         if (timeout)
 563                 chip->vendor.timeout_a = usecs_to_jiffies(timeout * scale);
 564         timeout = be32_to_cpu(timeout_cap->b);
 565         if (timeout)
 566                 chip->vendor.timeout_b = usecs_to_jiffies(timeout * scale);
 567         timeout = be32_to_cpu(timeout_cap->c);
 568         if (timeout)
 569                 chip->vendor.timeout_c = usecs_to_jiffies(timeout * scale);
 570         timeout = be32_to_cpu(timeout_cap->d);
 571         if (timeout)
 572                 chip->vendor.timeout_d = usecs_to_jiffies(timeout * scale);
 573
 574 duration:
 575         tpm_cmd.header.in = tpm_getcap_header;
 576         tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
 577         tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
 578         tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
 579
 580         rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
 581                         "attempting to determine the durations");
 582         if (rc)
 583                 return;
 584
 585         if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
 586             be32_to_cpu(tpm_cmd.header.out.length)
 587             != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
 588                 return;
 589
 590         duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
 591         chip->vendor.duration[TPM_SHORT] =
 592             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
 593         chip->vendor.duration[TPM_MEDIUM] =
 594             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
 595         chip->vendor.duration[TPM_LONG] =
 596             usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
 597
 598         /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
 599          * value wrong and apparently reports msecs rather than usecs. So we
 600          * fix up the resulting too-small TPM_SHORT value to make things work.
 601          * We also scale the TPM_MEDIUM and -_LONG values by 1000.
 602          */
 603         if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
 604                 chip->vendor.duration[TPM_SHORT] = HZ;
 605                 chip->vendor.duration[TPM_MEDIUM] *= 1000;
 606                 chip->vendor.duration[TPM_LONG] *= 1000;
 607                 chip->vendor.duration_adjusted = true;
 608                 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
 609         }
 610 }
 611 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
 612
 613 void tpm_continue_selftest(struct tpm_chip *chip)
 614 {
 615         u8 data[] = {
 616                 0, 193,                 /* TPM_TAG_RQU_COMMAND */
 617                 0, 0, 0, 10,            /* length */
 618                 0, 0, 0, 83,            /* TPM_ORD_ContinueSelfTest */
 619         };
 620
 621         tpm_transmit(chip, data, sizeof(data));
 622 }
 623 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
 624
 625 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
 626                         char *buf)
 627 {
 628         cap_t cap;
 629         ssize_t rc;
 630
 631         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 632                          "attempting to determine the permanent enabled state");
 633         if (rc)
 634                 return 0;
 635
 636         rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
 637         return rc;
 638 }
 639 EXPORT_SYMBOL_GPL(tpm_show_enabled);
 640
 641 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
 642                         char *buf)
 643 {
 644         cap_t cap;
 645         ssize_t rc;
 646
 647         rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
 648                          "attempting to determine the permanent active state");
 649         if (rc)
 650                 return 0;
 651
 652         rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
 653         return rc;
 654 }
 655 EXPORT_SYMBOL_GPL(tpm_show_active);
 656
 657 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
 658                         char *buf)
 659 {
 660         cap_t cap;
 661         ssize_t rc;
 662
 663         rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
 664                          "attempting to determine the owner state");
 665         if (rc)
 666                 return 0;
 667
 668         rc = sprintf(buf, "%d\n", cap.owned);
 669         return rc;
 670 }
 671 EXPORT_SYMBOL_GPL(tpm_show_owned);
 672
 673 ssize_t tpm_show_temp_deactivated(struct device * dev,
 674                                 struct device_attribute * attr, char *buf)
 675 {
 676         cap_t cap;
 677         ssize_t rc;
 678
 679         rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
 680                          "attempting to determine the temporary state");
 681         if (rc)
 682                 return 0;
 683
 684         rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
 685         return rc;
 686 }
 687 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
 688
 689 /*
 690  * tpm_chip_find_get - return tpm_chip for given chip number
 691  */
 692 static struct tpm_chip *tpm_chip_find_get(int chip_num)
 693 {
 694         struct tpm_chip *pos, *chip = NULL;
 695
 696         rcu_read_lock();
 697         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
 698                 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
 699                         continue;
 700
 701                 if (try_module_get(pos->dev->driver->owner)) {
 702                         chip = pos;
 703                         break;
 704                 }
 705         }
 706         rcu_read_unlock();
 707         return chip;
 708 }
 709
 710 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
 711 #define READ_PCR_RESULT_SIZE 30
 712 static struct tpm_input_header pcrread_header = {
 713         .tag = TPM_TAG_RQU_COMMAND,
 714         .length = cpu_to_be32(14),
 715         .ordinal = TPM_ORDINAL_PCRREAD
 716 };
 717
 718 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
 719 {
 720         int rc;
 721         struct tpm_cmd_t cmd;
 722
 723         cmd.header.in = pcrread_header;
 724         cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
 725         rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
 726                           "attempting to read a pcr value");
 727
 728         if (rc == 0)
 729                 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
 730                        TPM_DIGEST_SIZE);
 731         return rc;
 732 }
 733
 734 /**
 735  * tpm_pcr_read - read a pcr value
 736  * @chip_num:   tpm idx # or ANY
 737  * @pcr_idx:    pcr idx to retrieve
 738  * @res_buf:    TPM_PCR value
 739  *              size of res_buf is 20 bytes (or NULL if you don't care)
 740  *
 741  * The TPM driver should be built-in, but for whatever reason it
 742  * isn't, protect against the chip disappearing, by incrementing
 743  * the module usage count.
 744  */
 745 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
 746 {
 747         struct tpm_chip *chip;
 748         int rc;
 749
 750         chip = tpm_chip_find_get(chip_num);
 751         if (chip == NULL)
 752                 return -ENODEV;
 753         rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
 754         tpm_chip_put(chip);
 755         return rc;
 756 }
 757 EXPORT_SYMBOL_GPL(tpm_pcr_read);
 758
 759 /**
 760  * tpm_pcr_extend - extend pcr value with hash
 761  * @chip_num:   tpm idx # or AN&
 762  * @pcr_idx:    pcr idx to extend
 763  * @hash:       hash value used to extend pcr value
 764  *
 765  * The TPM driver should be built-in, but for whatever reason it
 766  * isn't, protect against the chip disappearing, by incrementing
 767  * the module usage count.
 768  */
 769 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
 770 #define EXTEND_PCR_RESULT_SIZE 34
 771 static struct tpm_input_header pcrextend_header = {
 772         .tag = TPM_TAG_RQU_COMMAND,
 773         .length = cpu_to_be32(34),
 774         .ordinal = TPM_ORD_PCR_EXTEND
 775 };
 776
 777 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
 778 {
 779         struct tpm_cmd_t cmd;
 780         int rc;
 781         struct tpm_chip *chip;
 782
 783         chip = tpm_chip_find_get(chip_num);
 784         if (chip == NULL)
 785                 return -ENODEV;
 786
 787         cmd.header.in = pcrextend_header;
 788         cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
 789         memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
 790         rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
 791                           "attempting extend a PCR value");
 792
 793         tpm_chip_put(chip);
 794         return rc;
 795 }
 796 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
 797
 798 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
 799 {
 800         struct tpm_chip *chip;
 801         int rc;
 802
 803         chip = tpm_chip_find_get(chip_num);
 804         if (chip == NULL)
 805                 return -ENODEV;
 806
 807         rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
 808
 809         tpm_chip_put(chip);
 810         return rc;
 811 }
 812 EXPORT_SYMBOL_GPL(tpm_send);
 813
 814 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
 815                       char *buf)
 816 {
 817         cap_t cap;
 818         u8 digest[TPM_DIGEST_SIZE];
 819         ssize_t rc;
 820         int i, j, num_pcrs;
 821         char *str = buf;
 822         struct tpm_chip *chip = dev_get_drvdata(dev);
 823
 824         rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
 825                         "attempting to determine the number of PCRS");
 826         if (rc)
 827                 return 0;
 828
 829         num_pcrs = be32_to_cpu(cap.num_pcrs);
 830         for (i = 0; i < num_pcrs; i++) {
 831                 rc = __tpm_pcr_read(chip, i, digest);
 832                 if (rc)
 833                         break;
 834                 str += sprintf(str, "PCR-%02d: ", i);
 835                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 836                         str += sprintf(str, "%02X ", digest[j]);
 837                 str += sprintf(str, "\n");
 838         }
 839         return str - buf;
 840 }
 841 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
 842
 843 #define  READ_PUBEK_RESULT_SIZE 314
 844 #define TPM_ORD_READPUBEK cpu_to_be32(124)
 845 struct tpm_input_header tpm_readpubek_header = {
 846         .tag = TPM_TAG_RQU_COMMAND,
 847         .length = cpu_to_be32(30),
 848         .ordinal = TPM_ORD_READPUBEK
 849 };
 850
 851 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
 852                        char *buf)
 853 {
 854         u8 *data;
 855         struct tpm_cmd_t tpm_cmd;
 856         ssize_t err;
 857         int i, rc;
 858         char *str = buf;
 859
 860         struct tpm_chip *chip = dev_get_drvdata(dev);
 861
 862         tpm_cmd.header.in = tpm_readpubek_header;
 863         err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
 864                         "attempting to read the PUBEK");
 865         if (err)
 866                 goto out;
 867
 868         /*
 869            ignore header 10 bytes
 870            algorithm 32 bits (1 == RSA )
 871            encscheme 16 bits
 872            sigscheme 16 bits
 873            parameters (RSA 12->bytes: keybit, #primes, expbit)
 874            keylenbytes 32 bits
 875            256 byte modulus
 876            ignore checksum 20 bytes
 877          */
 878         data = tpm_cmd.params.readpubek_out_buffer;
 879         str +=
 880             sprintf(str,
 881                     "Algorithm: %02X %02X %02X %02X\n"
 882                     "Encscheme: %02X %02X\n"
 883                     "Sigscheme: %02X %02X\n"
 884                     "Parameters: %02X %02X %02X %02X "
 885                     "%02X %02X %02X %02X "
 886                     "%02X %02X %02X %02X\n"
 887                     "Modulus length: %d\n"
 888                     "Modulus:\n",
 889                     data[0], data[1], data[2], data[3],
 890                     data[4], data[5],
 891                     data[6], data[7],
 892                     data[12], data[13], data[14], data[15],
 893                     data[16], data[17], data[18], data[19],
 894                     data[20], data[21], data[22], data[23],
 895                     be32_to_cpu(*((__be32 *) (data + 24))));
 896
 897         for (i = 0; i < 256; i++) {
 898                 str += sprintf(str, "%02X ", data[i + 28]);
 899                 if ((i + 1) % 16 == 0)
 900                         str += sprintf(str, "\n");
 901         }
 902 out:
 903         rc = str - buf;
 904         return rc;
 905 }
 906 EXPORT_SYMBOL_GPL(tpm_show_pubek);
 907
 908
 909 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
 910                       char *buf)
 911 {
 912         cap_t cap;
 913         ssize_t rc;
 914         char *str = buf;
 915
 916         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 917                         "attempting to determine the manufacturer");
 918         if (rc)
 919                 return 0;
 920         str += sprintf(str, "Manufacturer: 0x%x\n",
 921                        be32_to_cpu(cap.manufacturer_id));
 922
 923         rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
 924                         "attempting to determine the 1.1 version");
 925         if (rc)
 926                 return 0;
 927         str += sprintf(str,
 928                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 929                        cap.tpm_version.Major, cap.tpm_version.Minor,
 930                        cap.tpm_version.revMajor, cap.tpm_version.revMinor);
 931         return str - buf;
 932 }
 933 EXPORT_SYMBOL_GPL(tpm_show_caps);
 934
 935 ssize_t tpm_show_caps_1_2(struct device * dev,
 936                           struct device_attribute * attr, char *buf)
 937 {
 938         cap_t cap;
 939         ssize_t rc;
 940         char *str = buf;
 941
 942         rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
 943                         "attempting to determine the manufacturer");
 944         if (rc)
 945                 return 0;
 946         str += sprintf(str, "Manufacturer: 0x%x\n",
 947                        be32_to_cpu(cap.manufacturer_id));
 948         rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
 949                          "attempting to determine the 1.2 version");
 950         if (rc)
 951                 return 0;
 952         str += sprintf(str,
 953                        "TCG version: %d.%d\nFirmware version: %d.%d\n",
 954                        cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
 955                        cap.tpm_version_1_2.revMajor,
 956                        cap.tpm_version_1_2.revMinor);
 957         return str - buf;
 958 }
 959 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
 960
 961 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
 962                           char *buf)
 963 {
 964         struct tpm_chip *chip = dev_get_drvdata(dev);
 965
 966         if (chip->vendor.duration[TPM_LONG] == 0)
 967                 return 0;
 968
 969         return sprintf(buf, "%d %d %d [%s]\n",
 970                        jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
 971                        jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
 972                        jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
 973                        chip->vendor.duration_adjusted
 974                        ? "adjusted" : "original");
 975 }
 976 EXPORT_SYMBOL_GPL(tpm_show_durations);
 977
 978 ssize_t tpm_show_timeouts(struct device *dev, struct device_attribute *attr,
 979                           char *buf)
 980 {
 981         struct tpm_chip *chip = dev_get_drvdata(dev);
 982
 983         return sprintf(buf, "%d %d %d %d [%s]\n",
 984                        jiffies_to_usecs(chip->vendor.timeout_a),
 985                        jiffies_to_usecs(chip->vendor.timeout_b),
 986                        jiffies_to_usecs(chip->vendor.timeout_c),
 987                        jiffies_to_usecs(chip->vendor.timeout_d),
 988                        chip->vendor.timeout_adjusted
 989                        ? "adjusted" : "original");
 990 }
 991 EXPORT_SYMBOL_GPL(tpm_show_timeouts);
 992
 993 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
 994                         const char *buf, size_t count)
 995 {
 996         struct tpm_chip *chip = dev_get_drvdata(dev);
 997         if (chip == NULL)
 998                 return 0;
 999
1000         chip->vendor.cancel(chip);
1001         return count;
1002 }
1003 EXPORT_SYMBOL_GPL(tpm_store_cancel);
1004
1005 /*
1006  * Device file system interface to the TPM
1007  *
1008  * It's assured that the chip will be opened just once,
1009  * by the check of is_open variable, which is protected
1010  * by driver_lock.
1011  */
1012 int tpm_open(struct inode *inode, struct file *file)
1013 {
1014         int minor = iminor(inode);
1015         struct tpm_chip *chip = NULL, *pos;
1016
1017         rcu_read_lock();
1018         list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
1019                 if (pos->vendor.miscdev.minor == minor) {
1020                         chip = pos;
1021                         get_device(chip->dev);
1022                         break;
1023                 }
1024         }
1025         rcu_read_unlock();
1026
1027         if (!chip)
1028                 return -ENODEV;
1029
1030         if (test_and_set_bit(0, &chip->is_open)) {
1031                 dev_dbg(chip->dev, "Another process owns this TPM\n");
1032                 put_device(chip->dev);
1033                 return -EBUSY;
1034         }
1035
1036         chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1037         if (chip->data_buffer == NULL) {
1038                 clear_bit(0, &chip->is_open);
1039                 put_device(chip->dev);
1040                 return -ENOMEM;
1041         }
1042
1043         atomic_set(&chip->data_pending, 0);
1044
1045         file->private_data = chip;
1046         return 0;
1047 }
1048 EXPORT_SYMBOL_GPL(tpm_open);
1049
1050 /*
1051  * Called on file close
1052  */
1053 int tpm_release(struct inode *inode, struct file *file)
1054 {
1055         struct tpm_chip *chip = file->private_data;
1056
1057         del_singleshot_timer_sync(&chip->user_read_timer);
1058         flush_work_sync(&chip->work);
1059         file->private_data = NULL;
1060         atomic_set(&chip->data_pending, 0);
1061         kfree(chip->data_buffer);
1062         clear_bit(0, &chip->is_open);
1063         put_device(chip->dev);
1064         return 0;
1065 }
1066 EXPORT_SYMBOL_GPL(tpm_release);
1067
1068 ssize_t tpm_write(struct file *file, const char __user *buf,
1069                   size_t size, loff_t *off)
1070 {
1071         struct tpm_chip *chip = file->private_data;
1072         size_t in_size = size, out_size;
1073
1074         /* cannot perform a write until the read has cleared
1075            either via tpm_read or a user_read_timer timeout */
1076         while (atomic_read(&chip->data_pending) != 0)
1077                 msleep(TPM_TIMEOUT);
1078
1079         mutex_lock(&chip->buffer_mutex);
1080
1081         if (in_size > TPM_BUFSIZE)
1082                 in_size = TPM_BUFSIZE;
1083
1084         if (copy_from_user
1085             (chip->data_buffer, (void __user *) buf, in_size)) {
1086                 mutex_unlock(&chip->buffer_mutex);
1087                 return -EFAULT;
1088         }
1089
1090         /* atomic tpm command send and result receive */
1091         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1092
1093         atomic_set(&chip->data_pending, out_size);
1094         mutex_unlock(&chip->buffer_mutex);
1095
1096         /* Set a timeout by which the reader must come claim the result */
1097         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1098
1099         return in_size;
1100 }
1101 EXPORT_SYMBOL_GPL(tpm_write);
1102
1103 ssize_t tpm_read(struct file *file, char __user *buf,
1104                  size_t size, loff_t *off)
1105 {
1106         struct tpm_chip *chip = file->private_data;
1107         ssize_t ret_size;
1108
1109         del_singleshot_timer_sync(&chip->user_read_timer);
1110         flush_work_sync(&chip->work);
1111         ret_size = atomic_read(&chip->data_pending);
1112         atomic_set(&chip->data_pending, 0);
1113         if (ret_size > 0) {     /* relay data */
1114                 if (size < ret_size)
1115                         ret_size = size;
1116
1117                 mutex_lock(&chip->buffer_mutex);
1118                 if (copy_to_user(buf, chip->data_buffer, ret_size))
1119                         ret_size = -EFAULT;
1120                 mutex_unlock(&chip->buffer_mutex);
1121         }
1122
1123         return ret_size;
1124 }
1125 EXPORT_SYMBOL_GPL(tpm_read);
1126
1127 void tpm_remove_hardware(struct device *dev)
1128 {
1129         struct tpm_chip *chip = dev_get_drvdata(dev);
1130
1131         if (chip == NULL) {
1132                 dev_err(dev, "No device data found\n");
1133                 return;
1134         }
1135
1136         spin_lock(&driver_lock);
1137         list_del_rcu(&chip->list);
1138         spin_unlock(&driver_lock);
1139         synchronize_rcu();
1140
1141         misc_deregister(&chip->vendor.miscdev);
1142         sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1143         tpm_bios_log_teardown(chip->bios_dir);
1144
1145         /* write it this way to be explicit (chip->dev == dev) */
1146         put_device(chip->dev);
1147 }
1148 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1149
1150 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1151 #define SAVESTATE_RESULT_SIZE 10
1152
1153 static struct tpm_input_header savestate_header = {
1154         .tag = TPM_TAG_RQU_COMMAND,
1155         .length = cpu_to_be32(10),
1156         .ordinal = TPM_ORD_SAVESTATE
1157 };
1158
1159 /*
1160  * We are about to suspend. Save the TPM state
1161  * so that it can be restored.
1162  */
1163 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1164 {
1165         struct tpm_chip *chip = dev_get_drvdata(dev);
1166         struct tpm_cmd_t cmd;
1167         int rc;
1168
1169         u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1170
1171         if (chip == NULL)
1172                 return -ENODEV;
1173
1174         /* for buggy tpm, flush pcrs with extend to selected dummy */
1175         if (tpm_suspend_pcr) {
1176                 cmd.header.in = pcrextend_header;
1177                 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1178                 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1179                        TPM_DIGEST_SIZE);
1180                 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1181                                   "extending dummy pcr before suspend");
1182         }
1183
1184         /* now do the actual savestate */
1185         cmd.header.in = savestate_header;
1186         rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1187                           "sending savestate before suspend");
1188         return rc;
1189 }
1190 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1191
1192 /*
1193  * Resume from a power safe. The BIOS already restored
1194  * the TPM state.
1195  */
1196 int tpm_pm_resume(struct device *dev)
1197 {
1198         struct tpm_chip *chip = dev_get_drvdata(dev);
1199
1200         if (chip == NULL)
1201                 return -ENODEV;
1202
1203         return 0;
1204 }
1205 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1206
1207 /* In case vendor provided release function, call it too.*/
1208
1209 void tpm_dev_vendor_release(struct tpm_chip *chip)
1210 {
1211         if (chip->vendor.release)
1212                 chip->vendor.release(chip->dev);
1213
1214         clear_bit(chip->dev_num, dev_mask);
1215         kfree(chip->vendor.miscdev.name);
1216 }
1217 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1218
1219
1220 /*
1221  * Once all references to platform device are down to 0,
1222  * release all allocated structures.
1223  */
1224 void tpm_dev_release(struct device *dev)
1225 {
1226         struct tpm_chip *chip = dev_get_drvdata(dev);
1227
1228         tpm_dev_vendor_release(chip);
1229
1230         chip->release(dev);
1231         kfree(chip);
1232 }
1233 EXPORT_SYMBOL_GPL(tpm_dev_release);
1234
1235 /*
1236  * Called from tpm_<specific>.c probe function only for devices
1237  * the driver has determined it should claim.  Prior to calling
1238  * this function the specific probe function has called pci_enable_device
1239  * upon errant exit from this function specific probe function should call
1240  * pci_disable_device
1241  */
1242 struct tpm_chip *tpm_register_hardware(struct device *dev,
1243                                         const struct tpm_vendor_specific *entry)
1244 {
1245 #define DEVNAME_SIZE 7
1246
1247         char *devname;
1248         struct tpm_chip *chip;
1249
1250         /* Driver specific per-device data */
1251         chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1252         devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1253
1254         if (chip == NULL || devname == NULL)
1255                 goto out_free;
1256
1257         mutex_init(&chip->buffer_mutex);
1258         mutex_init(&chip->tpm_mutex);
1259         INIT_LIST_HEAD(&chip->list);
1260
1261         INIT_WORK(&chip->work, timeout_work);
1262
1263         setup_timer(&chip->user_read_timer, user_reader_timeout,
1264                         (unsigned long)chip);
1265
1266         memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1267
1268         chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1269
1270         if (chip->dev_num >= TPM_NUM_DEVICES) {
1271                 dev_err(dev, "No available tpm device numbers\n");
1272                 goto out_free;
1273         } else if (chip->dev_num == 0)
1274                 chip->vendor.miscdev.minor = TPM_MINOR;
1275         else
1276                 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1277
1278         set_bit(chip->dev_num, dev_mask);
1279
1280         scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1281         chip->vendor.miscdev.name = devname;
1282
1283         chip->vendor.miscdev.parent = dev;
1284         chip->dev = get_device(dev);
1285         chip->release = dev->release;
1286         dev->release = tpm_dev_release;
1287         dev_set_drvdata(dev, chip);
1288
1289         if (misc_register(&chip->vendor.miscdev)) {
1290                 dev_err(chip->dev,
1291                         "unable to misc_register %s, minor %d\n",
1292                         chip->vendor.miscdev.name,
1293                         chip->vendor.miscdev.minor);
1294                 put_device(chip->dev);
1295                 return NULL;
1296         }
1297
1298         if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1299                 misc_deregister(&chip->vendor.miscdev);
1300                 put_device(chip->dev);
1301
1302                 return NULL;
1303         }
1304
1305         chip->bios_dir = tpm_bios_log_setup(devname);
1306
1307         /* Make chip available */
1308         spin_lock(&driver_lock);
1309         list_add_rcu(&chip->list, &tpm_chip_list);
1310         spin_unlock(&driver_lock);
1311
1312         return chip;
1313
1314 out_free:
1315         kfree(chip);
1316         kfree(devname);
1317         return NULL;
1318 }
1319 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1320
1321 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1322 MODULE_DESCRIPTION("TPM Driver");
1323 MODULE_VERSION("2.0");
1324 MODULE_LICENSE("GPL");