drivers/tpm/tpm_tis_st33zp24_spi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * STMicroelectronics TPM ST33ZP24 SPI UBOOT driver
   4  *
   5  * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
   6  * Author(s): Christophe Ricard <christophe-h.ricard@st.com> for STMicroelectronics.
   7  *
   8  * Description: Device driver for ST33ZP24 SPI TPM TCG.
   9  *
  10  * This device driver implements the TPM interface as defined in
  11  * the TCG TPM Interface Spec version 1.21, revision 1.0 and the
  12  * STMicroelectronics Protocol Stack Specification version 1.2.0.
  13  */
  14
  15 #include <common.h>
  16 #include <dm.h>
  17 #include <fdtdec.h>
  18 #include <log.h>
  19 #include <spi.h>
  20 #include <tpm-v1.h>
  21 #include <errno.h>
  22 #include <linux/types.h>
  23 #include <asm/unaligned.h>
  24 #include <linux/compat.h>
  25
  26 #include "tpm_tis.h"
  27 #include "tpm_internal.h"
  28
  29 #define TPM_ACCESS                      0x0
  30 #define TPM_STS                         0x18
  31 #define TPM_DATA_FIFO                   0x24
  32
  33 #define LOCALITY0                       0
  34
  35 #define TPM_DATA_FIFO                           0x24
  36 #define TPM_INTF_CAPABILITY                     0x14
  37
  38 #define TPM_DUMMY_BYTE                          0x00
  39 #define TPM_WRITE_DIRECTION                     0x80
  40
  41 #define MAX_SPI_LATENCY                         15
  42 #define LOCALITY0                               0
  43
  44 #define ST33ZP24_OK                                     0x5A
  45 #define ST33ZP24_UNDEFINED_ERR                          0x80
  46 #define ST33ZP24_BADLOCALITY                            0x81
  47 #define ST33ZP24_TISREGISTER_UKNOWN                     0x82
  48 #define ST33ZP24_LOCALITY_NOT_ACTIVATED                 0x83
  49 #define ST33ZP24_HASH_END_BEFORE_HASH_START             0x84
  50 #define ST33ZP24_BAD_COMMAND_ORDER                      0x85
  51 #define ST33ZP24_INCORECT_RECEIVED_LENGTH               0x86
  52 #define ST33ZP24_TPM_FIFO_OVERFLOW                      0x89
  53 #define ST33ZP24_UNEXPECTED_READ_FIFO                   0x8A
  54 #define ST33ZP24_UNEXPECTED_WRITE_FIFO                  0x8B
  55 #define ST33ZP24_CMDRDY_SET_WHEN_PROCESSING_HASH_END    0x90
  56 #define ST33ZP24_DUMMY_BYTES                            0x00
  57
  58 /*
  59  * TPM command can be up to 2048 byte, A TPM response can be up to
  60  * 1024 byte.
  61  * Between command and response, there are latency byte (up to 15
  62  * usually on st33zp24 2 are enough).
  63  *
  64  * Overall when sending a command and expecting an answer we need if
  65  * worst case:
  66  * 2048 (for the TPM command) + 1024 (for the TPM answer).  We need
  67  * some latency byte before the answer is available (max 15).
  68  * We have 2048 + 1024 + 15.
  69  */
  70 #define ST33ZP24_SPI_BUFFER_SIZE (TPM_BUFSIZE + (TPM_BUFSIZE / 2) +\
  71                                   MAX_SPI_LATENCY)
  72
  73 struct st33zp24_spi_phy {
  74         int latency;
  75
  76         u8 tx_buf[ST33ZP24_SPI_BUFFER_SIZE];
  77         u8 rx_buf[ST33ZP24_SPI_BUFFER_SIZE];
  78 };
  79
  80 static int st33zp24_spi_status_to_errno(u8 code)
  81 {
  82         switch (code) {
  83         case ST33ZP24_OK:
  84                 return 0;
  85         case ST33ZP24_UNDEFINED_ERR:
  86         case ST33ZP24_BADLOCALITY:
  87         case ST33ZP24_TISREGISTER_UKNOWN:
  88         case ST33ZP24_LOCALITY_NOT_ACTIVATED:
  89         case ST33ZP24_HASH_END_BEFORE_HASH_START:
  90         case ST33ZP24_BAD_COMMAND_ORDER:
  91         case ST33ZP24_UNEXPECTED_READ_FIFO:
  92         case ST33ZP24_UNEXPECTED_WRITE_FIFO:
  93         case ST33ZP24_CMDRDY_SET_WHEN_PROCESSING_HASH_END:
  94                 return -EPROTO;
  95         case ST33ZP24_INCORECT_RECEIVED_LENGTH:
  96         case ST33ZP24_TPM_FIFO_OVERFLOW:
  97                 return -EMSGSIZE;
  98         case ST33ZP24_DUMMY_BYTES:
  99                 return -ENOSYS;
 100         }
 101         return code;
 102 }
 103
 104 /*
 105  * st33zp24_spi_send
 106  * Send byte to TPM register according to the ST33ZP24 SPI protocol.
 107  * @param: tpm, the chip description
 108  * @param: tpm_register, the tpm tis register where the data should be written
 109  * @param: tpm_data, the tpm_data to write inside the tpm_register
 110  * @param: tpm_size, The length of the data
 111  * @return: should be zero if success else a negative error code.
 112  */
 113 static int st33zp24_spi_write(struct udevice *dev, u8 tpm_register,
 114                               const u8 *tpm_data, size_t tpm_size)
 115 {
 116         int total_length = 0, ret;
 117         struct spi_slave *slave = dev_get_parent_priv(dev);
 118         struct st33zp24_spi_phy *phy = dev_get_platdata(dev);
 119
 120         u8 *tx_buf = (u8 *)phy->tx_buf;
 121         u8 *rx_buf = phy->rx_buf;
 122
 123         tx_buf[total_length++] = TPM_WRITE_DIRECTION | LOCALITY0;
 124         tx_buf[total_length++] = tpm_register;
 125
 126         if (tpm_size > 0 && tpm_register == TPM_DATA_FIFO) {
 127                 tx_buf[total_length++] = tpm_size >> 8;
 128                 tx_buf[total_length++] = tpm_size;
 129         }
 130         memcpy(tx_buf + total_length, tpm_data, tpm_size);
 131         total_length += tpm_size;
 132
 133         memset(tx_buf + total_length, TPM_DUMMY_BYTE, phy->latency);
 134
 135         total_length += phy->latency;
 136
 137         ret = spi_claim_bus(slave);
 138         if (ret < 0)
 139                 return ret;
 140
 141         ret = spi_xfer(slave, total_length * 8, tx_buf, rx_buf,
 142                        SPI_XFER_BEGIN | SPI_XFER_END);
 143         if (ret < 0)
 144                 return ret;
 145
 146         spi_release_bus(slave);
 147
 148         if (ret == 0)
 149                 ret = rx_buf[total_length - 1];
 150
 151         return st33zp24_spi_status_to_errno(ret);
 152 }
 153
 154 /*
 155  * spi_st33zp24_spi_read8_reg
 156  * Recv byte from the TIS register according to the ST33ZP24 SPI protocol.
 157  * @param: tpm, the chip description
 158  * @param: tpm_loc, the locality to read register from
 159  * @param: tpm_register, the tpm tis register where the data should be read
 160  * @param: tpm_data, the TPM response
 161  * @param: tpm_size, tpm TPM response size to read.
 162  * @return: should be zero if success else a negative error code.
 163  */
 164 static u8 st33zp24_spi_read8_reg(struct udevice *dev, u8 tpm_register,
 165                                  u8 *tpm_data, size_t tpm_size)
 166 {
 167         int total_length = 0, ret;
 168         struct spi_slave *slave = dev_get_parent_priv(dev);
 169         struct st33zp24_spi_phy *phy = dev_get_platdata(dev);
 170
 171         u8 *tx_buf = (u8 *)phy->tx_buf;
 172         u8 *rx_buf = phy->rx_buf;
 173
 174         /* Pre-Header */
 175         tx_buf[total_length++] = LOCALITY0;
 176         tx_buf[total_length++] = tpm_register;
 177
 178         memset(&tx_buf[total_length], TPM_DUMMY_BYTE,
 179                phy->latency + tpm_size);
 180         total_length += phy->latency + tpm_size;
 181
 182         ret = spi_claim_bus(slave);
 183         if (ret < 0)
 184                 return 0;
 185
 186         ret = spi_xfer(slave, total_length * 8, tx_buf, rx_buf,
 187                        SPI_XFER_BEGIN | SPI_XFER_END);
 188         if (ret < 0)
 189                 return 0;
 190
 191         spi_release_bus(slave);
 192
 193         if (tpm_size > 0 && ret == 0) {
 194                 ret = rx_buf[total_length - tpm_size - 1];
 195                 memcpy(tpm_data, rx_buf + total_length - tpm_size, tpm_size);
 196         }
 197         return ret;
 198 }
 199
 200 /*
 201  * st33zp24_spi_recv
 202  * Recv byte from the TIS register according to the ST33ZP24 SPI protocol.
 203  * @param: phy_id, the phy description
 204  * @param: tpm_register, the tpm tis register where the data should be read
 205  * @param: tpm_data, the TPM response
 206  * @param: tpm_size, tpm TPM response size to read.
 207  * @return: number of byte read successfully: should be one if success.
 208  */
 209 static int st33zp24_spi_read(struct udevice *dev, u8 tpm_register,
 210                              u8 *tpm_data, size_t tpm_size)
 211 {
 212         int ret;
 213
 214         ret = st33zp24_spi_read8_reg(dev, tpm_register, tpm_data, tpm_size);
 215         if (!st33zp24_spi_status_to_errno(ret))
 216                 return tpm_size;
 217
 218         return ret;
 219 }
 220
 221 static int st33zp24_spi_evaluate_latency(struct udevice *dev)
 222 {
 223         int latency = 1, status = 0;
 224         u8 data = 0;
 225         struct st33zp24_spi_phy *phy = dev_get_platdata(dev);
 226
 227         while (!status && latency < MAX_SPI_LATENCY) {
 228                 phy->latency = latency;
 229                 status = st33zp24_spi_read8_reg(dev, TPM_INTF_CAPABILITY,
 230                                                 &data, 1);
 231                 latency++;
 232         }
 233         if (status < 0)
 234                 return status;
 235         if (latency == MAX_SPI_LATENCY)
 236                 return -ENODEV;
 237
 238         return latency - 1;
 239 }
 240
 241 /*
 242  * st33zp24_spi_release_locality release the active locality
 243  * @param: chip, the tpm chip description.
 244  */
 245 static void st33zp24_spi_release_locality(struct udevice *dev)
 246 {
 247         u8 data = TPM_ACCESS_ACTIVE_LOCALITY;
 248
 249         st33zp24_spi_write(dev, TPM_ACCESS, &data, 1);
 250 }
 251
 252 /*
 253  * st33zp24_spi_check_locality if the locality is active
 254  * @param: chip, the tpm chip description
 255  * @return: the active locality or -EACCES.
 256  */
 257 static int st33zp24_spi_check_locality(struct udevice *dev)
 258 {
 259         u8 data;
 260         u8 status;
 261         struct tpm_chip *chip = dev_get_priv(dev);
 262
 263         status = st33zp24_spi_read(dev, TPM_ACCESS, &data, 1);
 264         if (status && (data &
 265                 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
 266                 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
 267                 return chip->locality;
 268
 269         return -EACCES;
 270 }
 271
 272 /*
 273  * st33zp24_spi_request_locality request the TPM locality
 274  * @param: chip, the chip description
 275  * @return: the active locality or negative value.
 276  */
 277 static int st33zp24_spi_request_locality(struct udevice *dev)
 278 {
 279         unsigned long start, stop;
 280         long ret;
 281         u8 data;
 282         struct tpm_chip *chip = dev_get_priv(dev);
 283
 284         if (st33zp24_spi_check_locality(dev) == chip->locality)
 285                 return chip->locality;
 286
 287         data = TPM_ACCESS_REQUEST_USE;
 288         ret = st33zp24_spi_write(dev, TPM_ACCESS, &data, 1);
 289         if (ret < 0)
 290                 return ret;
 291
 292         /* wait for locality activated */
 293         start = get_timer(0);
 294         stop = chip->timeout_a;
 295         do {
 296                 if (st33zp24_spi_check_locality(dev) >= 0)
 297                         return chip->locality;
 298                 udelay(TPM_TIMEOUT_MS * 1000);
 299         } while  (get_timer(start) < stop);
 300
 301         return -EACCES;
 302 }
 303
 304 /*
 305  * st33zp24_spi_status return the TPM_STS register
 306  * @param: chip, the tpm chip description
 307  * @return: the TPM_STS register value.
 308  */
 309 static u8 st33zp24_spi_status(struct udevice *dev)
 310 {
 311         u8 data;
 312
 313         st33zp24_spi_read(dev, TPM_STS, &data, 1);
 314         return data;
 315 }
 316
 317 /*
 318  * st33zp24_spi_get_burstcount return the burstcount address 0x19 0x1A
 319  * @param: chip, the chip description
 320  * return: the burstcount or -TPM_DRIVER_ERR in case of error.
 321  */
 322 static int st33zp24_spi_get_burstcount(struct udevice *dev)
 323 {
 324         struct tpm_chip *chip = dev_get_priv(dev);
 325         unsigned long start, stop;
 326         int burstcnt, status;
 327         u8 tpm_reg, temp;
 328
 329         /* wait for burstcount */
 330         start = get_timer(0);
 331         stop = chip->timeout_d;
 332         do {
 333                 tpm_reg = TPM_STS + 1;
 334                 status = st33zp24_spi_read(dev, tpm_reg, &temp, 1);
 335                 if (status < 0)
 336                         return -EBUSY;
 337
 338                 tpm_reg = TPM_STS + 2;
 339                 burstcnt = temp;
 340                 status = st33zp24_spi_read(dev, tpm_reg, &temp, 1);
 341                 if (status < 0)
 342                         return -EBUSY;
 343
 344                 burstcnt |= temp << 8;
 345                 if (burstcnt)
 346                         return burstcnt;
 347                 udelay(TIS_SHORT_TIMEOUT_MS * 1000);
 348         } while (get_timer(start) < stop);
 349
 350         return -EBUSY;
 351 }
 352
 353 /*
 354  * st33zp24_spi_cancel, cancel the current command execution or
 355  * set STS to COMMAND READY.
 356  * @param: chip, tpm_chip description.
 357  */
 358 static void st33zp24_spi_cancel(struct udevice *dev)
 359 {
 360         u8 data;
 361
 362         data = TPM_STS_COMMAND_READY;
 363         st33zp24_spi_write(dev, TPM_STS, &data, 1);
 364 }
 365
 366 /*
 367  * st33zp24_spi_wait_for_stat wait for a TPM_STS value
 368  * @param: chip, the tpm chip description
 369  * @param: mask, the value mask to wait
 370  * @param: timeout, the timeout
 371  * @param: status,
 372  * @return: the tpm status, 0 if success, -ETIME if timeout is reached.
 373  */
 374 static int st33zp24_spi_wait_for_stat(struct udevice *dev, u8 mask,
 375                                   unsigned long timeout, int *status)
 376 {
 377         unsigned long start, stop;
 378
 379         /* Check current status */
 380         *status = st33zp24_spi_status(dev);
 381         if ((*status & mask) == mask)
 382                 return 0;
 383
 384         start = get_timer(0);
 385         stop = timeout;
 386         do {
 387                 udelay(TPM_TIMEOUT_MS * 1000);
 388                 *status = st33zp24_spi_status(dev);
 389                 if ((*status & mask) == mask)
 390                         return 0;
 391         } while (get_timer(start) < stop);
 392
 393         return -ETIME;
 394 }
 395
 396 /*
 397  * st33zp24_spi_recv_data receive data
 398  * @param: chip, the tpm chip description
 399  * @param: buf, the buffer where the data are received
 400  * @param: count, the number of data to receive
 401  * @return: the number of bytes read from TPM FIFO.
 402  */
 403 static int st33zp24_spi_recv_data(struct udevice *dev, u8 *buf, size_t count)
 404 {
 405         struct tpm_chip *chip = dev_get_priv(dev);
 406         int size = 0, burstcnt, len, ret, status;
 407
 408         while (size < count &&
 409                st33zp24_spi_wait_for_stat(dev, TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 410                                 chip->timeout_c, &status) == 0) {
 411                 burstcnt = st33zp24_spi_get_burstcount(dev);
 412                 if (burstcnt < 0)
 413                         return burstcnt;
 414                 len = min_t(int, burstcnt, count - size);
 415                 ret = st33zp24_spi_read(dev, TPM_DATA_FIFO, buf + size, len);
 416                 if (ret < 0)
 417                         return ret;
 418
 419                 size += len;
 420         }
 421         return size;
 422 }
 423
 424 /*
 425  * st33zp24_spi_recv received TPM response through TPM phy.
 426  * @param: chip, tpm_chip description.
 427  * @param: buf, the buffer to store data.
 428  * @param: count, the number of bytes that can received (sizeof buf).
 429  * @return: Returns zero in case of success else -EIO.
 430  */
 431 static int st33zp24_spi_recv(struct udevice *dev, u8 *buf, size_t count)
 432 {
 433         struct tpm_chip *chip = dev_get_priv(dev);
 434         int size;
 435         unsigned int expected;
 436
 437         if (!chip)
 438                 return -ENODEV;
 439
 440         if (count < TPM_HEADER_SIZE) {
 441                 size = -EIO;
 442                 goto out;
 443         }
 444
 445         size = st33zp24_spi_recv_data(dev, buf, TPM_HEADER_SIZE);
 446         if (size < TPM_HEADER_SIZE) {
 447                 debug("TPM error, unable to read header\n");
 448                 goto out;
 449         }
 450
 451         expected = get_unaligned_be32(buf + 2);
 452         if (expected > count || expected < TPM_HEADER_SIZE) {
 453                 size = -EIO;
 454                 goto out;
 455         }
 456
 457         size += st33zp24_spi_recv_data(dev, &buf[TPM_HEADER_SIZE],
 458                                    expected - TPM_HEADER_SIZE);
 459         if (size < expected) {
 460                 debug("TPM error, unable to read remaining bytes of result\n");
 461                 size = -EIO;
 462                 goto out;
 463         }
 464
 465 out:
 466         st33zp24_spi_cancel(dev);
 467         st33zp24_spi_release_locality(dev);
 468
 469         return size;
 470 }
 471
 472 /*
 473  * st33zp24_spi_send send TPM commands through TPM phy.
 474  * @param: chip, tpm_chip description.
 475  * @param: buf, the buffer to send.
 476  * @param: len, the number of bytes to send.
 477  * @return: Returns zero in case of success else the negative error code.
 478  */
 479 static int st33zp24_spi_send(struct udevice *dev, const u8 *buf, size_t len)
 480 {
 481         struct tpm_chip *chip = dev_get_priv(dev);
 482         u32 i, size;
 483         int burstcnt, ret, status;
 484         u8 data, tpm_stat;
 485
 486         if (!chip)
 487                 return -ENODEV;
 488         if (len < TPM_HEADER_SIZE)
 489                 return -EIO;
 490
 491         ret = st33zp24_spi_request_locality(dev);
 492         if (ret < 0)
 493                 return ret;
 494
 495         tpm_stat = st33zp24_spi_status(dev);
 496         if ((tpm_stat & TPM_STS_COMMAND_READY) == 0) {
 497                 st33zp24_spi_cancel(dev);
 498                 if (st33zp24_spi_wait_for_stat(dev, TPM_STS_COMMAND_READY,
 499                                                chip->timeout_b, &status) < 0) {
 500                         ret = -ETIME;
 501                         goto out_err;
 502                 }
 503         }
 504
 505         for (i = 0; i < len - 1;) {
 506                 burstcnt = st33zp24_spi_get_burstcount(dev);
 507                 if (burstcnt < 0)
 508                         return burstcnt;
 509
 510                 size = min_t(int, len - i - 1, burstcnt);
 511                 ret = st33zp24_spi_write(dev, TPM_DATA_FIFO, buf + i, size);
 512                 if (ret < 0)
 513                         goto out_err;
 514
 515                 i += size;
 516         }
 517
 518         tpm_stat = st33zp24_spi_status(dev);
 519         if ((tpm_stat & TPM_STS_DATA_EXPECT) == 0) {
 520                 ret = -EIO;
 521                 goto out_err;
 522         }
 523
 524         ret = st33zp24_spi_write(dev, TPM_DATA_FIFO, buf + len - 1, 1);
 525         if (ret < 0)
 526                 goto out_err;
 527
 528         tpm_stat = st33zp24_spi_status(dev);
 529         if ((tpm_stat & TPM_STS_DATA_EXPECT) != 0) {
 530                 ret = -EIO;
 531                 goto out_err;
 532         }
 533
 534         data = TPM_STS_GO;
 535         ret = st33zp24_spi_write(dev, TPM_STS, &data, 1);
 536         if (ret < 0)
 537                 goto out_err;
 538
 539         return len;
 540
 541 out_err:
 542         st33zp24_spi_cancel(dev);
 543         st33zp24_spi_release_locality(dev);
 544
 545         return ret;
 546 }
 547
 548 static int st33zp24_spi_cleanup(struct udevice *dev)
 549 {
 550         st33zp24_spi_cancel(dev);
 551         /*
 552          * The TPM needs some time to clean up here,
 553          * so we sleep rather than keeping the bus busy
 554          */
 555         mdelay(2);
 556         st33zp24_spi_release_locality(dev);
 557
 558         return 0;
 559 }
 560
 561 static int st33zp24_spi_init(struct udevice *dev)
 562 {
 563         struct tpm_chip *chip = dev_get_priv(dev);
 564         struct st33zp24_spi_phy *phy = dev_get_platdata(dev);
 565
 566         chip->is_open = 1;
 567
 568         /* Default timeouts - these could move to the device tree */
 569         chip->timeout_a = TIS_SHORT_TIMEOUT_MS;
 570         chip->timeout_b = TIS_LONG_TIMEOUT_MS;
 571         chip->timeout_c = TIS_SHORT_TIMEOUT_MS;
 572         chip->timeout_d = TIS_SHORT_TIMEOUT_MS;
 573
 574         chip->locality = LOCALITY0;
 575
 576         phy->latency = st33zp24_spi_evaluate_latency(dev);
 577         if (phy->latency <= 0)
 578                 return -ENODEV;
 579
 580         /*
 581          * A timeout query to TPM can be placed here.
 582          * Standard timeout values are used so far
 583          */
 584
 585         return 0;
 586 }
 587
 588 static int st33zp24_spi_open(struct udevice *dev)
 589 {
 590         struct tpm_chip *chip = dev_get_priv(dev);
 591         int rc;
 592
 593         debug("%s: start\n", __func__);
 594         if (chip->is_open)
 595                 return -EBUSY;
 596
 597         rc = st33zp24_spi_init(dev);
 598         if (rc < 0)
 599                 chip->is_open = 0;
 600
 601         return rc;
 602 }
 603
 604 static int st33zp24_spi_close(struct udevice *dev)
 605 {
 606         struct tpm_chip *chip = dev_get_priv(dev);
 607
 608         if (chip->is_open) {
 609                 st33zp24_spi_release_locality(dev);
 610                 chip->is_open = 0;
 611                 chip->vend_dev = 0;
 612         }
 613
 614         return 0;
 615 }
 616
 617 static int st33zp24_spi_get_desc(struct udevice *dev, char *buf, int size)
 618 {
 619         struct tpm_chip *chip = dev_get_priv(dev);
 620
 621         if (size < 50)
 622                 return -ENOSPC;
 623
 624         return snprintf(buf, size, "1.2 TPM (%s, chip type %s device-id 0x%x)",
 625                         chip->is_open ? "open" : "closed",
 626                         dev->name,
 627                         chip->vend_dev >> 16);
 628 }
 629
 630 const struct tpm_ops st33zp24_spi_tpm_ops = {
 631         .open = st33zp24_spi_open,
 632         .close = st33zp24_spi_close,
 633         .recv = st33zp24_spi_recv,
 634         .send = st33zp24_spi_send,
 635         .cleanup = st33zp24_spi_cleanup,
 636         .get_desc = st33zp24_spi_get_desc,
 637 };
 638
 639 static int st33zp24_spi_probe(struct udevice *dev)
 640 {
 641         struct tpm_chip_priv *uc_priv = dev_get_uclass_priv(dev);
 642
 643         uc_priv->duration_ms[TPM_SHORT] = TIS_SHORT_TIMEOUT_MS;
 644         uc_priv->duration_ms[TPM_MEDIUM] = TIS_LONG_TIMEOUT_MS;
 645         uc_priv->duration_ms[TPM_LONG] = TIS_LONG_TIMEOUT_MS;
 646         uc_priv->retry_time_ms = TPM_TIMEOUT_MS;
 647
 648         debug("ST33ZP24 SPI TPM from STMicroelectronics found\n");
 649
 650         return 0;
 651 }
 652
 653 static int st33zp24_spi_remove(struct udevice *dev)
 654 {
 655         st33zp24_spi_release_locality(dev);
 656
 657         return 0;
 658 }
 659
 660 static const struct udevice_id st33zp24_spi_ids[] = {
 661         { .compatible = "st,st33zp24-spi" },
 662         { }
 663 };
 664
 665 U_BOOT_DRIVER(st33zp24_spi_spi) = {
 666         .name   = "st33zp24-spi",
 667         .id     = UCLASS_TPM,
 668         .of_match = of_match_ptr(st33zp24_spi_ids),
 669         .probe  = st33zp24_spi_probe,
 670         .remove = st33zp24_spi_remove,
 671         .ops = &st33zp24_spi_tpm_ops,
 672         .priv_auto_alloc_size = sizeof(struct tpm_chip),
 673         .platdata_auto_alloc_size = sizeof(struct st33zp24_spi_phy),
 674 };