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/sched.h>
  27 #include <linux/poll.h>
  28 #include <linux/spinlock.h>
  29 #include "tpm.h"
  30
  31 enum tpm_const {
  32         TPM_MINOR = 224,        /* officially assigned */
  33         TPM_BUFSIZE = 2048,
  34         TPM_NUM_DEVICES = 256,
  35         TPM_NUM_MASK_ENTRIES = TPM_NUM_DEVICES / (8 * sizeof(int))
  36 };
  37
  38   /* PCI configuration addresses */
  39 enum tpm_pci_config_addr {
  40         PCI_GEN_PMCON_1 = 0xA0,
  41         PCI_GEN1_DEC = 0xE4,
  42         PCI_LPC_EN = 0xE6,
  43         PCI_GEN2_DEC = 0xEC
  44 };
  45
  46 enum tpm_config {
  47         TPM_LOCK_REG = 0x0D,
  48         TPM_INTERUPT_REG = 0x0A,
  49         TPM_BASE_ADDR_LO = 0x08,
  50         TPM_BASE_ADDR_HI = 0x09,
  51         TPM_UNLOCK_VALUE = 0x55,
  52         TPM_LOCK_VALUE = 0xAA,
  53         TPM_DISABLE_INTERUPT_VALUE = 0x00
  54 };
  55
  56
  57 static LIST_HEAD(tpm_chip_list);
  58 static DEFINE_SPINLOCK(driver_lock);
  59 static int dev_mask[TPM_NUM_MASK_ENTRIES];
  60
  61 static void user_reader_timeout(unsigned long ptr)
  62 {
  63         struct tpm_chip *chip = (struct tpm_chip *) ptr;
  64
  65         down(&chip->buffer_mutex);
  66         atomic_set(&chip->data_pending, 0);
  67         memset(chip->data_buffer, 0, TPM_BUFSIZE);
  68         up(&chip->buffer_mutex);
  69 }
  70
  71 /*
  72  * Initialize the LPC bus and enable the TPM ports
  73  */
  74 int tpm_lpc_bus_init(struct pci_dev *pci_dev, u16 base)
  75 {
  76         u32 lpcenable, tmp;
  77         int is_lpcm = 0;
  78
  79         switch (pci_dev->vendor) {
  80         case PCI_VENDOR_ID_INTEL:
  81                 switch (pci_dev->device) {
  82                 case PCI_DEVICE_ID_INTEL_82801CA_12:
  83                 case PCI_DEVICE_ID_INTEL_82801DB_12:
  84                         is_lpcm = 1;
  85                         break;
  86                 }
  87                 /* init ICH (enable LPC) */
  88                 pci_read_config_dword(pci_dev, PCI_GEN1_DEC, &lpcenable);
  89                 lpcenable |= 0x20000000;
  90                 pci_write_config_dword(pci_dev, PCI_GEN1_DEC, lpcenable);
  91
  92                 if (is_lpcm) {
  93                         pci_read_config_dword(pci_dev, PCI_GEN1_DEC,
  94                                               &lpcenable);
  95                         if ((lpcenable & 0x20000000) == 0) {
  96                                 dev_err(&pci_dev->dev,
  97                                         "cannot enable LPC\n");
  98                                 return -ENODEV;
  99                         }
 100                 }
 101
 102                 /* initialize TPM registers */
 103                 pci_read_config_dword(pci_dev, PCI_GEN2_DEC, &tmp);
 104
 105                 if (!is_lpcm)
 106                         tmp = (tmp & 0xFFFF0000) | (base & 0xFFF0);
 107                 else
 108                         tmp =
 109                             (tmp & 0xFFFF0000) | (base & 0xFFF0) |
 110                             0x00000001;
 111
 112                 pci_write_config_dword(pci_dev, PCI_GEN2_DEC, tmp);
 113
 114                 if (is_lpcm) {
 115                         pci_read_config_dword(pci_dev, PCI_GEN_PMCON_1,
 116                                               &tmp);
 117                         tmp |= 0x00000004;      /* enable CLKRUN */
 118                         pci_write_config_dword(pci_dev, PCI_GEN_PMCON_1,
 119                                                tmp);
 120                 }
 121                 break;
 122         case PCI_VENDOR_ID_AMD:
 123                 /* nothing yet */
 124                 break;
 125         }
 126
 127         tpm_write_index(TPM_LOCK_REG, TPM_UNLOCK_VALUE);
 128         tpm_write_index(TPM_INTERUPT_REG, TPM_DISABLE_INTERUPT_VALUE);
 129         tpm_write_index(TPM_BASE_ADDR_LO, base);
 130         tpm_write_index(TPM_BASE_ADDR_HI, (base & 0xFF00) >> 8);
 131         tpm_write_index(TPM_LOCK_REG, TPM_LOCK_VALUE);
 132
 133         return 0;
 134 }
 135
 136 EXPORT_SYMBOL_GPL(tpm_lpc_bus_init);
 137
 138 /*
 139  * Internal kernel interface to transmit TPM commands
 140  */
 141 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
 142                             size_t bufsiz)
 143 {
 144         ssize_t len;
 145         u32 count;
 146         unsigned long stop;
 147
 148         count = be32_to_cpu(*((__be32 *) (buf + 2)));
 149
 150         if (count == 0)
 151                 return -ENODATA;
 152         if (count > bufsiz) {
 153                 dev_err(&chip->pci_dev->dev,
 154                         "invalid count value %x %zx \n", count, bufsiz);
 155                 return -E2BIG;
 156         }
 157
 158         down(&chip->tpm_mutex);
 159
 160         if ((len = chip->vendor->send(chip, (u8 *) buf, count)) < 0) {
 161                 dev_err(&chip->pci_dev->dev,
 162                         "tpm_transmit: tpm_send: error %zd\n", len);
 163                 return len;
 164         }
 165
 166         stop = jiffies + 2 * 60 * HZ;
 167         do {
 168                 u8 status = inb(chip->vendor->base + 1);
 169                 if ((status & chip->vendor->req_complete_mask) ==
 170                     chip->vendor->req_complete_val) {
 171                         goto out_recv;
 172                 }
 173                 msleep(TPM_TIMEOUT); /* CHECK */
 174                 rmb();
 175         } while (time_before(jiffies, stop));
 176
 177
 178         chip->vendor->cancel(chip);
 179         dev_err(&chip->pci_dev->dev, "Time expired\n");
 180         up(&chip->tpm_mutex);
 181         return -EIO;
 182
 183 out_recv:
 184         len = chip->vendor->recv(chip, (u8 *) buf, bufsiz);
 185         if (len < 0)
 186                 dev_err(&chip->pci_dev->dev,
 187                         "tpm_transmit: tpm_recv: error %zd\n", len);
 188         up(&chip->tpm_mutex);
 189         return len;
 190 }
 191
 192 #define TPM_DIGEST_SIZE 20
 193 #define CAP_PCR_RESULT_SIZE 18
 194 static const u8 cap_pcr[] = {
 195         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 196         0, 0, 0, 22,            /* length */
 197         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 198         0, 0, 0, 5,
 199         0, 0, 0, 4,
 200         0, 0, 1, 1
 201 };
 202
 203 #define READ_PCR_RESULT_SIZE 30
 204 static const u8 pcrread[] = {
 205         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 206         0, 0, 0, 14,            /* length */
 207         0, 0, 0, 21,            /* TPM_ORD_PcrRead */
 208         0, 0, 0, 0              /* PCR index */
 209 };
 210
 211 static ssize_t show_pcrs(struct device *dev, struct device_attribute *attr, char *buf)
 212 {
 213         u8 data[READ_PCR_RESULT_SIZE];
 214         ssize_t len;
 215         int i, j, num_pcrs;
 216         __be32 index;
 217         char *str = buf;
 218
 219         struct tpm_chip *chip =
 220             pci_get_drvdata(to_pci_dev(dev));
 221         if (chip == NULL)
 222                 return -ENODEV;
 223
 224         memcpy(data, cap_pcr, sizeof(cap_pcr));
 225         if ((len = tpm_transmit(chip, data, sizeof(data)))
 226             < CAP_PCR_RESULT_SIZE)
 227                 return len;
 228
 229         num_pcrs = be32_to_cpu(*((__be32 *) (data + 14)));
 230
 231         for (i = 0; i < num_pcrs; i++) {
 232                 memcpy(data, pcrread, sizeof(pcrread));
 233                 index = cpu_to_be32(i);
 234                 memcpy(data + 10, &index, 4);
 235                 if ((len = tpm_transmit(chip, data, sizeof(data)))
 236                     < READ_PCR_RESULT_SIZE)
 237                         return len;
 238                 str += sprintf(str, "PCR-%02d: ", i);
 239                 for (j = 0; j < TPM_DIGEST_SIZE; j++)
 240                         str += sprintf(str, "%02X ", *(data + 10 + j));
 241                 str += sprintf(str, "\n");
 242         }
 243         return str - buf;
 244 }
 245
 246 static DEVICE_ATTR(pcrs, S_IRUGO, show_pcrs, NULL);
 247
 248 #define  READ_PUBEK_RESULT_SIZE 314
 249 static const u8 readpubek[] = {
 250         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 251         0, 0, 0, 30,            /* length */
 252         0, 0, 0, 124,           /* TPM_ORD_ReadPubek */
 253 };
 254
 255 static ssize_t show_pubek(struct device *dev, struct device_attribute *attr, char *buf)
 256 {
 257         u8 *data;
 258         ssize_t len;
 259         int i, rc;
 260         char *str = buf;
 261
 262         struct tpm_chip *chip =
 263             pci_get_drvdata(to_pci_dev(dev));
 264         if (chip == NULL)
 265                 return -ENODEV;
 266
 267         data = kmalloc(READ_PUBEK_RESULT_SIZE, GFP_KERNEL);
 268         if (!data)
 269                 return -ENOMEM;
 270
 271         memcpy(data, readpubek, sizeof(readpubek));
 272         memset(data + sizeof(readpubek), 0, 20);        /* zero nonce */
 273
 274         if ((len = tpm_transmit(chip, data, READ_PUBEK_RESULT_SIZE)) <
 275             READ_PUBEK_RESULT_SIZE) {
 276                 rc = len;
 277                 goto out;
 278         }
 279
 280         /*
 281            ignore header 10 bytes
 282            algorithm 32 bits (1 == RSA )
 283            encscheme 16 bits
 284            sigscheme 16 bits
 285            parameters (RSA 12->bytes: keybit, #primes, expbit)
 286            keylenbytes 32 bits
 287            256 byte modulus
 288            ignore checksum 20 bytes
 289          */
 290
 291         str +=
 292             sprintf(str,
 293                     "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
 294                     "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
 295                     " %02X %02X %02X %02X %02X %02X %02X %02X\n"
 296                     "Modulus length: %d\nModulus: \n",
 297                     data[10], data[11], data[12], data[13], data[14],
 298                     data[15], data[16], data[17], data[22], data[23],
 299                     data[24], data[25], data[26], data[27], data[28],
 300                     data[29], data[30], data[31], data[32], data[33],
 301                     be32_to_cpu(*((__be32 *) (data + 32))));
 302
 303         for (i = 0; i < 256; i++) {
 304                 str += sprintf(str, "%02X ", data[i + 39]);
 305                 if ((i + 1) % 16 == 0)
 306                         str += sprintf(str, "\n");
 307         }
 308         rc = str - buf;
 309 out:
 310         kfree(data);
 311         return rc;
 312 }
 313
 314 static DEVICE_ATTR(pubek, S_IRUGO, show_pubek, NULL);
 315
 316 #define CAP_VER_RESULT_SIZE 18
 317 static const u8 cap_version[] = {
 318         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 319         0, 0, 0, 18,            /* length */
 320         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 321         0, 0, 0, 6,
 322         0, 0, 0, 0
 323 };
 324
 325 #define CAP_MANUFACTURER_RESULT_SIZE 18
 326 static const u8 cap_manufacturer[] = {
 327         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 328         0, 0, 0, 22,            /* length */
 329         0, 0, 0, 101,           /* TPM_ORD_GetCapability */
 330         0, 0, 0, 5,
 331         0, 0, 0, 4,
 332         0, 0, 1, 3
 333 };
 334
 335 static ssize_t show_caps(struct device *dev, struct device_attribute *attr, char *buf)
 336 {
 337         u8 data[sizeof(cap_manufacturer)];
 338         ssize_t len;
 339         char *str = buf;
 340
 341         struct tpm_chip *chip =
 342             pci_get_drvdata(to_pci_dev(dev));
 343         if (chip == NULL)
 344                 return -ENODEV;
 345
 346         memcpy(data, cap_manufacturer, sizeof(cap_manufacturer));
 347
 348         if ((len = tpm_transmit(chip, data, sizeof(data))) <
 349             CAP_MANUFACTURER_RESULT_SIZE)
 350                 return len;
 351
 352         str += sprintf(str, "Manufacturer: 0x%x\n",
 353                        be32_to_cpu(*((__be32 *) (data + 14))));
 354
 355         memcpy(data, cap_version, sizeof(cap_version));
 356
 357         if ((len = tpm_transmit(chip, data, sizeof(data))) <
 358             CAP_VER_RESULT_SIZE)
 359                 return len;
 360
 361         str +=
 362             sprintf(str, "TCG version: %d.%d\nFirmware version: %d.%d\n",
 363                     (int) data[14], (int) data[15], (int) data[16],
 364                     (int) data[17]);
 365
 366         return str - buf;
 367 }
 368
 369 static DEVICE_ATTR(caps, S_IRUGO, show_caps, NULL);
 370
 371 /*
 372  * Device file system interface to the TPM
 373  */
 374 int tpm_open(struct inode *inode, struct file *file)
 375 {
 376         int rc = 0, minor = iminor(inode);
 377         struct tpm_chip *chip = NULL, *pos;
 378
 379         spin_lock(&driver_lock);
 380
 381         list_for_each_entry(pos, &tpm_chip_list, list) {
 382                 if (pos->vendor->miscdev.minor == minor) {
 383                         chip = pos;
 384                         break;
 385                 }
 386         }
 387
 388         if (chip == NULL) {
 389                 rc = -ENODEV;
 390                 goto err_out;
 391         }
 392
 393         if (chip->num_opens) {
 394                 dev_dbg(&chip->pci_dev->dev,
 395                         "Another process owns this TPM\n");
 396                 rc = -EBUSY;
 397                 goto err_out;
 398         }
 399
 400         chip->num_opens++;
 401         pci_dev_get(chip->pci_dev);
 402
 403         spin_unlock(&driver_lock);
 404
 405         chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 406         if (chip->data_buffer == NULL) {
 407                 chip->num_opens--;
 408                 pci_dev_put(chip->pci_dev);
 409                 return -ENOMEM;
 410         }
 411
 412         atomic_set(&chip->data_pending, 0);
 413
 414         file->private_data = chip;
 415         return 0;
 416
 417 err_out:
 418         spin_unlock(&driver_lock);
 419         return rc;
 420 }
 421
 422 EXPORT_SYMBOL_GPL(tpm_open);
 423
 424 int tpm_release(struct inode *inode, struct file *file)
 425 {
 426         struct tpm_chip *chip = file->private_data;
 427
 428         file->private_data = NULL;
 429
 430         spin_lock(&driver_lock);
 431         chip->num_opens--;
 432         del_singleshot_timer_sync(&chip->user_read_timer);
 433         atomic_set(&chip->data_pending, 0);
 434
 435         pci_dev_put(chip->pci_dev);
 436         return 0;
 437 }
 438
 439 EXPORT_SYMBOL_GPL(tpm_release);
 440
 441 ssize_t tpm_write(struct file * file, const char __user * buf,
 442                   size_t size, loff_t * off)
 443 {
 444         struct tpm_chip *chip = file->private_data;
 445         int in_size = size, out_size;
 446
 447         /* cannot perform a write until the read has cleared
 448            either via tpm_read or a user_read_timer timeout */
 449         while (atomic_read(&chip->data_pending) != 0)
 450                 msleep(TPM_TIMEOUT);
 451
 452         down(&chip->buffer_mutex);
 453
 454         if (in_size > TPM_BUFSIZE)
 455                 in_size = TPM_BUFSIZE;
 456
 457         if (copy_from_user
 458             (chip->data_buffer, (void __user *) buf, in_size)) {
 459                 up(&chip->buffer_mutex);
 460                 return -EFAULT;
 461         }
 462
 463         /* atomic tpm command send and result receive */
 464         out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
 465
 466         atomic_set(&chip->data_pending, out_size);
 467         up(&chip->buffer_mutex);
 468
 469         /* Set a timeout by which the reader must come claim the result */
 470         mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
 471
 472         return in_size;
 473 }
 474
 475 EXPORT_SYMBOL_GPL(tpm_write);
 476
 477 ssize_t tpm_read(struct file * file, char __user * buf,
 478                  size_t size, loff_t * off)
 479 {
 480         struct tpm_chip *chip = file->private_data;
 481         int ret_size;
 482
 483         del_singleshot_timer_sync(&chip->user_read_timer);
 484         ret_size = atomic_read(&chip->data_pending);
 485         atomic_set(&chip->data_pending, 0);
 486         if (ret_size > 0) {     /* relay data */
 487                 if (size < ret_size)
 488                         ret_size = size;
 489
 490                 down(&chip->buffer_mutex);
 491                 if (copy_to_user
 492                     ((void __user *) buf, chip->data_buffer, ret_size))
 493                         ret_size = -EFAULT;
 494                 up(&chip->buffer_mutex);
 495         }
 496
 497         return ret_size;
 498 }
 499
 500 EXPORT_SYMBOL_GPL(tpm_read);
 501
 502 void __devexit tpm_remove(struct pci_dev *pci_dev)
 503 {
 504         struct tpm_chip *chip = pci_get_drvdata(pci_dev);
 505
 506         if (chip == NULL) {
 507                 dev_err(&pci_dev->dev, "No device data found\n");
 508                 return;
 509         }
 510
 511         spin_lock(&driver_lock);
 512
 513         list_del(&chip->list);
 514
 515         spin_unlock(&driver_lock);
 516
 517         pci_set_drvdata(pci_dev, NULL);
 518         misc_deregister(&chip->vendor->miscdev);
 519
 520         device_remove_file(&pci_dev->dev, &dev_attr_pubek);
 521         device_remove_file(&pci_dev->dev, &dev_attr_pcrs);
 522         device_remove_file(&pci_dev->dev, &dev_attr_caps);
 523
 524         pci_disable_device(pci_dev);
 525
 526         dev_mask[chip->dev_num / TPM_NUM_MASK_ENTRIES ] &= !(1 << (chip->dev_num % TPM_NUM_MASK_ENTRIES));
 527
 528         kfree(chip);
 529
 530         pci_dev_put(pci_dev);
 531 }
 532
 533 EXPORT_SYMBOL_GPL(tpm_remove);
 534
 535 static u8 savestate[] = {
 536         0, 193,                 /* TPM_TAG_RQU_COMMAND */
 537         0, 0, 0, 10,            /* blob length (in bytes) */
 538         0, 0, 0, 152            /* TPM_ORD_SaveState */
 539 };
 540
 541 /*
 542  * We are about to suspend. Save the TPM state
 543  * so that it can be restored.
 544  */
 545 int tpm_pm_suspend(struct pci_dev *pci_dev, pm_message_t pm_state)
 546 {
 547         struct tpm_chip *chip = pci_get_drvdata(pci_dev);
 548         if (chip == NULL)
 549                 return -ENODEV;
 550
 551         tpm_transmit(chip, savestate, sizeof(savestate));
 552         return 0;
 553 }
 554
 555 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
 556
 557 /*
 558  * Resume from a power safe. The BIOS already restored
 559  * the TPM state.
 560  */
 561 int tpm_pm_resume(struct pci_dev *pci_dev)
 562 {
 563         struct tpm_chip *chip = pci_get_drvdata(pci_dev);
 564
 565         if (chip == NULL)
 566                 return -ENODEV;
 567
 568         spin_lock(&driver_lock);
 569         tpm_lpc_bus_init(pci_dev, chip->vendor->base);
 570         spin_unlock(&driver_lock);
 571
 572         return 0;
 573 }
 574
 575 EXPORT_SYMBOL_GPL(tpm_pm_resume);
 576
 577 /*
 578  * Called from tpm_<specific>.c probe function only for devices
 579  * the driver has determined it should claim.  Prior to calling
 580  * this function the specific probe function has called pci_enable_device
 581  * upon errant exit from this function specific probe function should call
 582  * pci_disable_device
 583  */
 584 int tpm_register_hardware(struct pci_dev *pci_dev,
 585                           struct tpm_vendor_specific *entry)
 586 {
 587         char devname[7];
 588         struct tpm_chip *chip;
 589         int i, j;
 590
 591         /* Driver specific per-device data */
 592         chip = kmalloc(sizeof(*chip), GFP_KERNEL);
 593         if (chip == NULL)
 594                 return -ENOMEM;
 595
 596         memset(chip, 0, sizeof(struct tpm_chip));
 597
 598         init_MUTEX(&chip->buffer_mutex);
 599         init_MUTEX(&chip->tpm_mutex);
 600         INIT_LIST_HEAD(&chip->list);
 601
 602         init_timer(&chip->user_read_timer);
 603         chip->user_read_timer.function = user_reader_timeout;
 604         chip->user_read_timer.data = (unsigned long) chip;
 605
 606         chip->vendor = entry;
 607
 608         chip->dev_num = -1;
 609
 610         for (i = 0; i < TPM_NUM_MASK_ENTRIES; i++)
 611                 for (j = 0; j < 8 * sizeof(int); j++)
 612                         if ((dev_mask[i] & (1 << j)) == 0) {
 613                                 chip->dev_num =
 614                                     i * TPM_NUM_MASK_ENTRIES + j;
 615                                 dev_mask[i] |= 1 << j;
 616                                 goto dev_num_search_complete;
 617                         }
 618
 619 dev_num_search_complete:
 620         if (chip->dev_num < 0) {
 621                 dev_err(&pci_dev->dev,
 622                         "No available tpm device numbers\n");
 623                 kfree(chip);
 624                 return -ENODEV;
 625         } else if (chip->dev_num == 0)
 626                 chip->vendor->miscdev.minor = TPM_MINOR;
 627         else
 628                 chip->vendor->miscdev.minor = MISC_DYNAMIC_MINOR;
 629
 630         snprintf(devname, sizeof(devname), "%s%d", "tpm", chip->dev_num);
 631         chip->vendor->miscdev.name = devname;
 632
 633         chip->vendor->miscdev.dev = &(pci_dev->dev);
 634         chip->pci_dev = pci_dev_get(pci_dev);
 635
 636         if (misc_register(&chip->vendor->miscdev)) {
 637                 dev_err(&chip->pci_dev->dev,
 638                         "unable to misc_register %s, minor %d\n",
 639                         chip->vendor->miscdev.name,
 640                         chip->vendor->miscdev.minor);
 641                 pci_dev_put(pci_dev);
 642                 kfree(chip);
 643                 dev_mask[i] &= !(1 << j);
 644                 return -ENODEV;
 645         }
 646
 647         pci_set_drvdata(pci_dev, chip);
 648
 649         list_add(&chip->list, &tpm_chip_list);
 650
 651         device_create_file(&pci_dev->dev, &dev_attr_pubek);
 652         device_create_file(&pci_dev->dev, &dev_attr_pcrs);
 653         device_create_file(&pci_dev->dev, &dev_attr_caps);
 654
 655         return 0;
 656 }
 657
 658 EXPORT_SYMBOL_GPL(tpm_register_hardware);
 659
 660 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 661 MODULE_DESCRIPTION("TPM Driver");
 662 MODULE_VERSION("2.0");
 663 MODULE_LICENSE("GPL");