drivers/tpm/tpm_tis_i2c.c

   1 /*
   2  * Copyright (C) 2011 Infineon Technologies
   3  *
   4  * Authors:
   5  * Peter Huewe <huewe.external@infineon.com>
   6  *
   7  * Description:
   8  * Device driver for TCG/TCPA TPM (trusted platform module).
   9  * Specifications at www.trustedcomputinggroup.org
  10  *
  11  * This device driver implements the TPM interface as defined in
  12  * the TCG TPM Interface Spec version 1.2, revision 1.0 and the
  13  * Infineon I2C Protocol Stack Specification v0.20.
  14  *
  15  * It is based on the Linux kernel driver tpm.c from Leendert van
  16  * Dorn, Dave Safford, Reiner Sailer, and Kyleen Hall.
  17  *
  18  * Version: 2.1.1
  19  *
  20  * See file CREDITS for list of people who contributed to this
  21  * project.
  22  *
  23  * This program is free software; you can redistribute it and/or
  24  * modify it under the terms of the GNU General Public License as
  25  * published by the Free Software Foundation, version 2 of the
  26  * License.
  27  *
  28  * This program is distributed in the hope that it will be useful,
  29  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  30  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  31  * GNU General Public License for more details.
  32  *
  33  * You should have received a copy of the GNU General Public License
  34  * along with this program; if not, write to the Free Software
  35  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  36  * MA 02111-1307 USA
  37  */
  38
  39 #include <common.h>
  40 #include <dm.h>
  41 #include <fdtdec.h>
  42 #include <linux/compiler.h>
  43 #include <i2c.h>
  44 #include <tpm.h>
  45 #include <asm-generic/errno.h>
  46 #include <linux/types.h>
  47 #include <linux/unaligned/be_byteshift.h>
  48
  49 #include "tpm_private.h"
  50
  51 DECLARE_GLOBAL_DATA_PTR;
  52
  53 /* Address of the TPM on the I2C bus */
  54 #define TPM_I2C_ADDR            0x20
  55
  56 /* Max buffer size supported by our tpm */
  57 #define TPM_DEV_BUFSIZE         1260
  58
  59 /* Max number of iterations after i2c NAK */
  60 #define MAX_COUNT               3
  61
  62 /*
  63  * Max number of iterations after i2c NAK for 'long' commands
  64  *
  65  * We need this especially for sending TPM_READY, since the cleanup after the
  66  * transtion to the ready state may take some time, but it is unpredictable
  67  * how long it will take.
  68  */
  69 #define MAX_COUNT_LONG          50
  70
  71 #define SLEEP_DURATION          60      /* in usec */
  72 #define SLEEP_DURATION_LONG     210     /* in usec */
  73
  74 #define TPM_HEADER_SIZE         10
  75
  76 /*
  77  * Expected value for DIDVID register
  78  *
  79  * The only device the system knows about at this moment is Infineon slb9635.
  80  */
  81 #define TPM_TIS_I2C_DID_VID     0x000b15d1L
  82
  83 enum tis_access {
  84         TPM_ACCESS_VALID                = 0x80,
  85         TPM_ACCESS_ACTIVE_LOCALITY      = 0x20,
  86         TPM_ACCESS_REQUEST_PENDING      = 0x04,
  87         TPM_ACCESS_REQUEST_USE          = 0x02,
  88 };
  89
  90 enum tis_status {
  91         TPM_STS_VALID                   = 0x80,
  92         TPM_STS_COMMAND_READY           = 0x40,
  93         TPM_STS_GO                      = 0x20,
  94         TPM_STS_DATA_AVAIL              = 0x10,
  95         TPM_STS_DATA_EXPECT             = 0x08,
  96 };
  97
  98 enum tis_defaults {
  99         TIS_SHORT_TIMEOUT               = 750,  /* ms */
 100         TIS_LONG_TIMEOUT                = 2000, /* ms */
 101 };
 102
 103 /* expected value for DIDVID register */
 104 #define TPM_TIS_I2C_DID_VID_9635 0x000b15d1L
 105 #define TPM_TIS_I2C_DID_VID_9645 0x001a15d1L
 106
 107 enum i2c_chip_type {
 108         SLB9635,
 109         SLB9645,
 110         UNKNOWN,
 111 };
 112
 113 static const char * const chip_name[] = {
 114         [SLB9635] = "slb9635tt",
 115         [SLB9645] = "slb9645tt",
 116         [UNKNOWN] = "unknown/fallback to slb9635",
 117 };
 118
 119 #define TPM_ACCESS(l)                   (0x0000 | ((l) << 4))
 120 #define TPM_STS(l)                      (0x0001 | ((l) << 4))
 121 #define TPM_DATA_FIFO(l)                (0x0005 | ((l) << 4))
 122 #define TPM_DID_VID(l)                  (0x0006 | ((l) << 4))
 123
 124 /* Structure to store I2C TPM specific stuff */
 125 struct tpm_dev {
 126 #ifdef CONFIG_DM_I2C
 127         struct udevice *dev;
 128 #else
 129         uint addr;
 130 #endif
 131         u8 buf[TPM_DEV_BUFSIZE + sizeof(u8)];  /* Max buffer size + addr */
 132         enum i2c_chip_type chip_type;
 133 };
 134
 135 static struct tpm_dev tpm_dev = {
 136 #ifndef CONFIG_DM_I2C
 137         .addr = TPM_I2C_ADDR
 138 #endif
 139 };
 140
 141 static struct tpm_dev tpm_dev;
 142
 143 /*
 144  * iic_tpm_read() - read from TPM register
 145  * @addr: register address to read from
 146  * @buffer: provided by caller
 147  * @len: number of bytes to read
 148  *
 149  * Read len bytes from TPM register and put them into
 150  * buffer (little-endian format, i.e. first byte is put into buffer[0]).
 151  *
 152  * NOTE: TPM is big-endian for multi-byte values. Multi-byte
 153  * values have to be swapped.
 154  *
 155  * Return -EIO on error, 0 on success.
 156  */
 157 static int iic_tpm_read(u8 addr, u8 *buffer, size_t len)
 158 {
 159         int rc;
 160         int count;
 161         uint32_t addrbuf = addr;
 162
 163         if ((tpm_dev.chip_type == SLB9635) || (tpm_dev.chip_type == UNKNOWN)) {
 164                 /* slb9635 protocol should work in both cases */
 165                 for (count = 0; count < MAX_COUNT; count++) {
 166 #ifdef CONFIG_DM_I2C
 167                         rc = dm_i2c_write(tpm_dev.dev, 0, (uchar *)&addrbuf, 1);
 168 #else
 169                         rc = i2c_write(tpm_dev.addr, 0, 0,
 170                                        (uchar *)&addrbuf, 1);
 171 #endif
 172                         if (rc == 0)
 173                                 break;  /* Success, break to skip sleep */
 174                         udelay(SLEEP_DURATION);
 175                 }
 176                 if (rc)
 177                         return -rc;
 178
 179                 /* After the TPM has successfully received the register address
 180                  * it needs some time, thus we're sleeping here again, before
 181                  * retrieving the data
 182                  */
 183                 for (count = 0; count < MAX_COUNT; count++) {
 184                         udelay(SLEEP_DURATION);
 185 #ifdef CONFIG_DM_I2C
 186                         rc = dm_i2c_read(tpm_dev.dev, 0, buffer, len);
 187 #else
 188                         rc = i2c_read(tpm_dev.addr, 0, 0, buffer, len);
 189 #endif
 190                         if (rc == 0)
 191                                 break;  /* success, break to skip sleep */
 192                 }
 193         } else {
 194                 /*
 195                  * Use a combined read for newer chips.
 196                  * Unfortunately the smbus functions are not suitable due to
 197                  * the 32 byte limit of the smbus.
 198                  * Retries should usually not be needed, but are kept just to
 199                  * be safe on the safe side.
 200                  */
 201                 for (count = 0; count < MAX_COUNT; count++) {
 202 #ifdef CONFIG_DM_I2C
 203                         rc = dm_i2c_read(tpm_dev.dev, addr, buffer, len);
 204 #else
 205                         rc = i2c_read(tpm_dev.addr, addr, 1, buffer, len);
 206 #endif
 207                         if (rc == 0)
 208                                 break;  /* break here to skip sleep */
 209                         udelay(SLEEP_DURATION);
 210                 }
 211         }
 212
 213         /* Take care of 'guard time' */
 214         udelay(SLEEP_DURATION);
 215         if (rc)
 216                 return -rc;
 217
 218         return 0;
 219 }
 220
 221 static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,
 222                 unsigned int sleep_time, u8 max_count)
 223 {
 224         int rc = 0;
 225         int count;
 226
 227         /* Prepare send buffer */
 228 #ifndef CONFIG_DM_I2C
 229         tpm_dev.buf[0] = addr;
 230         memcpy(&(tpm_dev.buf[1]), buffer, len);
 231         buffer = tpm_dev.buf;
 232         len++;
 233 #endif
 234
 235         for (count = 0; count < max_count; count++) {
 236 #ifdef CONFIG_DM_I2C
 237                 rc = dm_i2c_write(tpm_dev.dev, addr, buffer, len);
 238 #else
 239                 rc = i2c_write(tpm_dev.addr, 0, 0, buffer, len);
 240 #endif
 241                 if (rc == 0)
 242                         break;  /* Success, break to skip sleep */
 243                 udelay(sleep_time);
 244         }
 245
 246         /* take care of 'guard time' */
 247         udelay(sleep_time);
 248         if (rc)
 249                 return -rc;
 250
 251         return 0;
 252 }
 253
 254 /*
 255  * iic_tpm_write() - write to TPM register
 256  * @addr: register address to write to
 257  * @buffer: containing data to be written
 258  * @len: number of bytes to write
 259  *
 260  * Write len bytes from provided buffer to TPM register (little
 261  * endian format, i.e. buffer[0] is written as first byte).
 262  *
 263  * NOTE: TPM is big-endian for multi-byte values. Multi-byte
 264  * values have to be swapped.
 265  *
 266  * NOTE: use this function instead of the iic_tpm_write_generic function.
 267  *
 268  * Return -EIO on error, 0 on success
 269  */
 270 static int iic_tpm_write(u8 addr, u8 *buffer, size_t len)
 271 {
 272         return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION,
 273                         MAX_COUNT);
 274 }
 275
 276 /*
 277  * This function is needed especially for the cleanup situation after
 278  * sending TPM_READY
 279  */
 280 static int iic_tpm_write_long(u8 addr, u8 *buffer, size_t len)
 281 {
 282         return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LONG,
 283                         MAX_COUNT_LONG);
 284 }
 285
 286 static int check_locality(struct tpm_chip *chip, int loc)
 287 {
 288         const u8 mask = TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID;
 289         u8 buf;
 290         int rc;
 291
 292         rc = iic_tpm_read(TPM_ACCESS(loc), &buf, 1);
 293         if (rc < 0)
 294                 return rc;
 295
 296         if ((buf & mask) == mask) {
 297                 chip->vendor.locality = loc;
 298                 return loc;
 299         }
 300
 301         return -1;
 302 }
 303
 304 static void release_locality(struct tpm_chip *chip, int loc, int force)
 305 {
 306         const u8 mask = TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID;
 307         u8 buf;
 308
 309         if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0)
 310                 return;
 311
 312         if (force || (buf & mask) == mask) {
 313                 buf = TPM_ACCESS_ACTIVE_LOCALITY;
 314                 iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
 315         }
 316 }
 317
 318 static int request_locality(struct tpm_chip *chip, int loc)
 319 {
 320         unsigned long start, stop;
 321         u8 buf = TPM_ACCESS_REQUEST_USE;
 322         int rc;
 323
 324         if (check_locality(chip, loc) >= 0)
 325                 return loc;  /* We already have the locality */
 326
 327         rc = iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
 328         if (rc)
 329                 return rc;
 330
 331         /* Wait for burstcount */
 332         start = get_timer(0);
 333         stop = chip->vendor.timeout_a;
 334         do {
 335                 if (check_locality(chip, loc) >= 0)
 336                         return loc;
 337                 udelay(TPM_TIMEOUT * 1000);
 338         } while (get_timer(start) < stop);
 339
 340         return -1;
 341 }
 342
 343 static u8 tpm_tis_i2c_status(struct tpm_chip *chip)
 344 {
 345         /* NOTE: Since i2c read may fail, return 0 in this case --> time-out */
 346         u8 buf;
 347
 348         if (iic_tpm_read(TPM_STS(chip->vendor.locality), &buf, 1) < 0)
 349                 return 0;
 350         else
 351                 return buf;
 352 }
 353
 354 static void tpm_tis_i2c_ready(struct tpm_chip *chip)
 355 {
 356         int rc;
 357
 358         /* This causes the current command to be aborted */
 359         u8 buf = TPM_STS_COMMAND_READY;
 360
 361         debug("%s\n", __func__);
 362         rc = iic_tpm_write_long(TPM_STS(chip->vendor.locality), &buf, 1);
 363         if (rc)
 364                 debug("%s: rc=%d\n", __func__, rc);
 365 }
 366
 367 static ssize_t get_burstcount(struct tpm_chip *chip)
 368 {
 369         unsigned long start, stop;
 370         ssize_t burstcnt;
 371         u8 addr, buf[3];
 372
 373         /* Wait for burstcount */
 374         /* XXX: Which timeout value? Spec has 2 answers (c & d) */
 375         start = get_timer(0);
 376         stop = chip->vendor.timeout_d;
 377         do {
 378                 /* Note: STS is little endian */
 379                 addr = TPM_STS(chip->vendor.locality) + 1;
 380                 if (iic_tpm_read(addr, buf, 3) < 0)
 381                         burstcnt = 0;
 382                 else
 383                         burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0];
 384
 385                 if (burstcnt)
 386                         return burstcnt;
 387                 udelay(TPM_TIMEOUT * 1000);
 388         } while (get_timer(start) < stop);
 389
 390         return -EBUSY;
 391 }
 392
 393 static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
 394                 int *status)
 395 {
 396         unsigned long start, stop;
 397
 398         /* Check current status */
 399         *status = tpm_tis_i2c_status(chip);
 400         if ((*status & mask) == mask)
 401                 return 0;
 402
 403         start = get_timer(0);
 404         stop = timeout;
 405         do {
 406                 udelay(TPM_TIMEOUT * 1000);
 407                 *status = tpm_tis_i2c_status(chip);
 408                 if ((*status & mask) == mask)
 409                         return 0;
 410         } while (get_timer(start) < stop);
 411
 412         return -ETIME;
 413 }
 414
 415 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 416 {
 417         size_t size = 0;
 418         ssize_t burstcnt;
 419         int rc;
 420
 421         while (size < count) {
 422                 burstcnt = get_burstcount(chip);
 423
 424                 /* burstcount < 0 -> tpm is busy */
 425                 if (burstcnt < 0)
 426                         return burstcnt;
 427
 428                 /* Limit received data to max left */
 429                 if (burstcnt > (count - size))
 430                         burstcnt = count - size;
 431
 432                 rc = iic_tpm_read(TPM_DATA_FIFO(chip->vendor.locality),
 433                                 &(buf[size]), burstcnt);
 434                 if (rc == 0)
 435                         size += burstcnt;
 436         }
 437
 438         return size;
 439 }
 440
 441 static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count)
 442 {
 443         int size = 0;
 444         int expected, status;
 445
 446         if (count < TPM_HEADER_SIZE) {
 447                 size = -EIO;
 448                 goto out;
 449         }
 450
 451         /* Read first 10 bytes, including tag, paramsize, and result */
 452         size = recv_data(chip, buf, TPM_HEADER_SIZE);
 453         if (size < TPM_HEADER_SIZE) {
 454                 error("Unable to read header\n");
 455                 goto out;
 456         }
 457
 458         expected = get_unaligned_be32(buf + TPM_RSP_SIZE_BYTE);
 459         if ((size_t)expected > count) {
 460                 error("Error size=%x, expected=%x, count=%x\n", size, expected,
 461                       count);
 462                 size = -EIO;
 463                 goto out;
 464         }
 465
 466         size += recv_data(chip, &buf[TPM_HEADER_SIZE],
 467                         expected - TPM_HEADER_SIZE);
 468         if (size < expected) {
 469                 error("Unable to read remainder of result\n");
 470                 size = -ETIME;
 471                 goto out;
 472         }
 473
 474         wait_for_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c, &status);
 475         if (status & TPM_STS_DATA_AVAIL) {  /* Retry? */
 476                 error("Error left over data\n");
 477                 size = -EIO;
 478                 goto out;
 479         }
 480
 481 out:
 482         tpm_tis_i2c_ready(chip);
 483         /*
 484          * The TPM needs some time to clean up here,
 485          * so we sleep rather than keeping the bus busy
 486          */
 487         udelay(2000);
 488         release_locality(chip, chip->vendor.locality, 0);
 489
 490         return size;
 491 }
 492
 493 static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
 494 {
 495         int rc, status;
 496         size_t burstcnt;
 497         size_t count = 0;
 498         int retry = 0;
 499         u8 sts = TPM_STS_GO;
 500
 501         debug("%s: len=%d\n", __func__, len);
 502         if (len > TPM_DEV_BUFSIZE)
 503                 return -E2BIG;  /* Command is too long for our tpm, sorry */
 504
 505         if (request_locality(chip, 0) < 0)
 506                 return -EBUSY;
 507
 508         status = tpm_tis_i2c_status(chip);
 509         if ((status & TPM_STS_COMMAND_READY) == 0) {
 510                 tpm_tis_i2c_ready(chip);
 511                 if (wait_for_stat(chip, TPM_STS_COMMAND_READY,
 512                                   chip->vendor.timeout_b, &status) < 0) {
 513                         rc = -ETIME;
 514                         goto out_err;
 515                 }
 516         }
 517
 518         burstcnt = get_burstcount(chip);
 519
 520         /* burstcount < 0 -> tpm is busy */
 521         if (burstcnt < 0)
 522                 return burstcnt;
 523
 524         while (count < len) {
 525                 udelay(300);
 526                 if (burstcnt > len - count)
 527                         burstcnt = len - count;
 528
 529 #ifdef CONFIG_TPM_TIS_I2C_BURST_LIMITATION
 530                 if (retry && burstcnt > CONFIG_TPM_TIS_I2C_BURST_LIMITATION)
 531                         burstcnt = CONFIG_TPM_TIS_I2C_BURST_LIMITATION;
 532 #endif /* CONFIG_TPM_TIS_I2C_BURST_LIMITATION */
 533
 534                 rc = iic_tpm_write(TPM_DATA_FIFO(chip->vendor.locality),
 535                                 &(buf[count]), burstcnt);
 536                 if (rc == 0)
 537                         count += burstcnt;
 538                 else {
 539                         debug("%s: error\n", __func__);
 540                         if (retry++ > 10) {
 541                                 rc = -EIO;
 542                                 goto out_err;
 543                         }
 544                         rc = wait_for_stat(chip, TPM_STS_VALID,
 545                                            chip->vendor.timeout_c, &status);
 546                         if (rc)
 547                                 goto out_err;
 548
 549                         if ((status & TPM_STS_DATA_EXPECT) == 0) {
 550                                 rc = -EIO;
 551                                 goto out_err;
 552                         }
 553                 }
 554         }
 555
 556         /* Go and do it */
 557         iic_tpm_write(TPM_STS(chip->vendor.locality), &sts, 1);
 558         debug("done\n");
 559
 560         return len;
 561
 562 out_err:
 563         debug("%s: out_err\n", __func__);
 564         tpm_tis_i2c_ready(chip);
 565         /*
 566          * The TPM needs some time to clean up here,
 567          * so we sleep rather than keeping the bus busy
 568          */
 569         udelay(2000);
 570         release_locality(chip, chip->vendor.locality, 0);
 571
 572         return rc;
 573 }
 574
 575 static struct tpm_vendor_specific tpm_tis_i2c = {
 576         .status = tpm_tis_i2c_status,
 577         .recv = tpm_tis_i2c_recv,
 578         .send = tpm_tis_i2c_send,
 579         .cancel = tpm_tis_i2c_ready,
 580         .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 581         .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 582         .req_canceled = TPM_STS_COMMAND_READY,
 583 };
 584
 585
 586 static enum i2c_chip_type tpm_vendor_chip_type(void)
 587 {
 588 #ifdef CONFIG_OF_CONTROL
 589         const void *blob = gd->fdt_blob;
 590
 591         if (fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9645_TPM) >= 0)
 592                 return SLB9645;
 593
 594         if (fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9635_TPM) >= 0)
 595                 return SLB9635;
 596 #endif
 597         return UNKNOWN;
 598 }
 599
 600 static int tpm_vendor_init_common(void)
 601 {
 602         struct tpm_chip *chip;
 603         u32 vendor;
 604         u32 expected_did_vid;
 605
 606         tpm_dev.chip_type = tpm_vendor_chip_type();
 607
 608         chip = tpm_register_hardware(&tpm_tis_i2c);
 609         if (chip < 0)
 610                 return -ENODEV;
 611
 612         /* Disable interrupts (not supported) */
 613         chip->vendor.irq = 0;
 614
 615         /* Default timeouts */
 616         chip->vendor.timeout_a = TIS_SHORT_TIMEOUT;
 617         chip->vendor.timeout_b = TIS_LONG_TIMEOUT;
 618         chip->vendor.timeout_c = TIS_SHORT_TIMEOUT;
 619         chip->vendor.timeout_d = TIS_SHORT_TIMEOUT;
 620
 621         if (request_locality(chip, 0) < 0)
 622                 return  -ENODEV;
 623
 624         /* Read four bytes from DID_VID register */
 625         if (iic_tpm_read(TPM_DID_VID(0), (uchar *)&vendor, 4) < 0) {
 626                 release_locality(chip, 0, 1);
 627                 return -EIO;
 628         }
 629
 630         if (tpm_dev.chip_type == SLB9635) {
 631                 vendor = be32_to_cpu(vendor);
 632                 expected_did_vid = TPM_TIS_I2C_DID_VID_9635;
 633         } else {
 634                 /* device id and byte order has changed for newer i2c tpms */
 635                 expected_did_vid = TPM_TIS_I2C_DID_VID_9645;
 636         }
 637
 638         if (tpm_dev.chip_type != UNKNOWN && vendor != expected_did_vid) {
 639                 error("Vendor id did not match! ID was %08x\n", vendor);
 640                 return -ENODEV;
 641         }
 642
 643         debug("1.2 TPM (chip type %s device-id 0x%X)\n",
 644               chip_name[tpm_dev.chip_type], vendor >> 16);
 645
 646         /*
 647          * A timeout query to TPM can be placed here.
 648          * Standard timeout values are used so far
 649          */
 650
 651         return 0;
 652 }
 653
 654 #ifdef CONFIG_DM_I2C
 655 /* Initialisation of i2c tpm */
 656 int tpm_vendor_init_dev(struct udevice *dev)
 657 {
 658         tpm_dev.dev = dev;
 659         return tpm_vendor_init_common();
 660 }
 661 #else
 662 /* Initialisation of i2c tpm */
 663 int tpm_vendor_init(uint32_t dev_addr)
 664 {
 665         uint old_addr;
 666         int rc = 0;
 667
 668         old_addr = tpm_dev.addr;
 669         if (dev_addr != 0)
 670                 tpm_dev.addr = dev_addr;
 671
 672         rc = tpm_vendor_init_common();
 673         if (rc)
 674                 tpm_dev.addr = old_addr;
 675
 676         return rc;
 677 }
 678 #endif
 679
 680 void tpm_vendor_cleanup(struct tpm_chip *chip)
 681 {
 682         release_locality(chip, chip->vendor.locality, 1);
 683 }