drivers/char/tpm/tpm_i2c_stm_st33.c

   1 /*
   2  * STMicroelectronics TPM I2C Linux driver for TPM ST33ZP24
   3  * Copyright (C) 2009, 2010  STMicroelectronics
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * STMicroelectronics version 1.2.0, Copyright (C) 2010
  20  * STMicroelectronics comes with ABSOLUTELY NO WARRANTY.
  21  * This is free software, and you are welcome to redistribute it
  22  * under certain conditions.
  23  *
  24  * @Author: Christophe RICARD tpmsupport@st.com
  25  *
  26  * @File: tpm_stm_st33_i2c.c
  27  *
  28  * @Synopsis:
  29  *      09/15/2010:     First shot driver tpm_tis driver for
  30                          lpc is used as model.
  31  */
  32
  33 #include <linux/pci.h>
  34 #include <linux/module.h>
  35 #include <linux/platform_device.h>
  36 #include <linux/i2c.h>
  37 #include <linux/fs.h>
  38 #include <linux/miscdevice.h>
  39 #include <linux/kernel.h>
  40 #include <linux/delay.h>
  41 #include <linux/init.h>
  42 #include <linux/wait.h>
  43 #include <linux/string.h>
  44 #include <linux/interrupt.h>
  45 #include <linux/spinlock.h>
  46 #include <linux/sysfs.h>
  47 #include <linux/gpio.h>
  48 #include <linux/sched.h>
  49 #include <linux/uaccess.h>
  50 #include <linux/io.h>
  51 #include <linux/slab.h>
  52
  53 #include "tpm.h"
  54 #include "tpm_i2c_stm_st33.h"
  55
  56 enum stm33zp24_access {
  57         TPM_ACCESS_VALID = 0x80,
  58         TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
  59         TPM_ACCESS_REQUEST_PENDING = 0x04,
  60         TPM_ACCESS_REQUEST_USE = 0x02,
  61 };
  62
  63 enum stm33zp24_status {
  64         TPM_STS_VALID = 0x80,
  65         TPM_STS_COMMAND_READY = 0x40,
  66         TPM_STS_GO = 0x20,
  67         TPM_STS_DATA_AVAIL = 0x10,
  68         TPM_STS_DATA_EXPECT = 0x08,
  69 };
  70
  71 enum stm33zp24_int_flags {
  72         TPM_GLOBAL_INT_ENABLE = 0x80,
  73         TPM_INTF_CMD_READY_INT = 0x080,
  74         TPM_INTF_FIFO_AVALAIBLE_INT = 0x040,
  75         TPM_INTF_WAKE_UP_READY_INT = 0x020,
  76         TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
  77         TPM_INTF_STS_VALID_INT = 0x002,
  78         TPM_INTF_DATA_AVAIL_INT = 0x001,
  79 };
  80
  81 enum tis_defaults {
  82         TIS_SHORT_TIMEOUT = 750,
  83         TIS_LONG_TIMEOUT = 2000,
  84 };
  85
  86 /*
  87  * write8_reg
  88  * Send byte to the TIS register according to the ST33ZP24 I2C protocol.
  89  * @param: tpm_register, the tpm tis register where the data should be written
  90  * @param: tpm_data, the tpm_data to write inside the tpm_register
  91  * @param: tpm_size, The length of the data
  92  * @return: Returns negative errno, or else the number of bytes written.
  93  */
  94 static int write8_reg(struct i2c_client *client, u8 tpm_register,
  95                       u8 *tpm_data, u16 tpm_size)
  96 {
  97         struct st33zp24_platform_data *pin_infos;
  98
  99         pin_infos = client->dev.platform_data;
 100
 101         pin_infos->tpm_i2c_buffer[0][0] = tpm_register;
 102         memcpy(&pin_infos->tpm_i2c_buffer[0][1], tpm_data, tpm_size);
 103         return i2c_master_send(client, pin_infos->tpm_i2c_buffer[0],
 104                                 tpm_size + 1);
 105 } /* write8_reg() */
 106
 107 /*
 108  * read8_reg
 109  * Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
 110  * @param: tpm_register, the tpm tis register where the data should be read
 111  * @param: tpm_data, the TPM response
 112  * @param: tpm_size, tpm TPM response size to read.
 113  * @return: number of byte read successfully: should be one if success.
 114  */
 115 static int read8_reg(struct i2c_client *client, u8 tpm_register,
 116                     u8 *tpm_data, int tpm_size)
 117 {
 118         u8 status = 0;
 119         u8 data;
 120
 121         data = TPM_DUMMY_BYTE;
 122         status = write8_reg(client, tpm_register, &data, 1);
 123         if (status == 2)
 124                 status = i2c_master_recv(client, tpm_data, tpm_size);
 125         return status;
 126 } /* read8_reg() */
 127
 128 /*
 129  * I2C_WRITE_DATA
 130  * Send byte to the TIS register according to the ST33ZP24 I2C protocol.
 131  * @param: client, the chip description
 132  * @param: tpm_register, the tpm tis register where the data should be written
 133  * @param: tpm_data, the tpm_data to write inside the tpm_register
 134  * @param: tpm_size, The length of the data
 135  * @return: number of byte written successfully: should be one if success.
 136  */
 137 #define I2C_WRITE_DATA(client, tpm_register, tpm_data, tpm_size) \
 138         (write8_reg(client, tpm_register | \
 139         TPM_WRITE_DIRECTION, tpm_data, tpm_size))
 140
 141 /*
 142  * I2C_READ_DATA
 143  * Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
 144  * @param: tpm, the chip description
 145  * @param: tpm_register, the tpm tis register where the data should be read
 146  * @param: tpm_data, the TPM response
 147  * @param: tpm_size, tpm TPM response size to read.
 148  * @return: number of byte read successfully: should be one if success.
 149  */
 150 #define I2C_READ_DATA(client, tpm_register, tpm_data, tpm_size) \
 151         (read8_reg(client, tpm_register, tpm_data, tpm_size))
 152
 153 /*
 154  * clear_interruption
 155  * clear the TPM interrupt register.
 156  * @param: tpm, the chip description
 157  */
 158 static void clear_interruption(struct i2c_client *client)
 159 {
 160         u8 interrupt;
 161         I2C_READ_DATA(client, TPM_INT_STATUS, &interrupt, 1);
 162         I2C_WRITE_DATA(client, TPM_INT_STATUS, &interrupt, 1);
 163         I2C_READ_DATA(client, TPM_INT_STATUS, &interrupt, 1);
 164 } /* clear_interruption() */
 165
 166 /*
 167  * _wait_for_interrupt_serirq_timeout
 168  * @param: tpm, the chip description
 169  * @param: timeout, the timeout of the interrupt
 170  * @return: the status of the interruption.
 171  */
 172 static long _wait_for_interrupt_serirq_timeout(struct tpm_chip *chip,
 173                                                 unsigned long timeout)
 174 {
 175         long status;
 176         struct i2c_client *client;
 177         struct st33zp24_platform_data *pin_infos;
 178
 179         client = (struct i2c_client *)TPM_VPRIV(chip);
 180         pin_infos = client->dev.platform_data;
 181
 182         status = wait_for_completion_interruptible_timeout(
 183                                         &pin_infos->irq_detection,
 184                                                 timeout);
 185         if (status > 0)
 186                 enable_irq(gpio_to_irq(pin_infos->io_serirq));
 187         gpio_direction_input(pin_infos->io_serirq);
 188
 189         return status;
 190 } /* wait_for_interrupt_serirq_timeout() */
 191
 192 static int wait_for_serirq_timeout(struct tpm_chip *chip, bool condition,
 193                                  unsigned long timeout)
 194 {
 195         int status = 2;
 196         struct i2c_client *client;
 197
 198         client = (struct i2c_client *)TPM_VPRIV(chip);
 199
 200         status = _wait_for_interrupt_serirq_timeout(chip, timeout);
 201         if (!status) {
 202                 status = -EBUSY;
 203         } else {
 204                 clear_interruption(client);
 205                 if (condition)
 206                         status = 1;
 207         }
 208         return status;
 209 }
 210
 211 /*
 212  * tpm_stm_i2c_cancel, cancel is not implemented.
 213  * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
 214  */
 215 static void tpm_stm_i2c_cancel(struct tpm_chip *chip)
 216 {
 217         struct i2c_client *client;
 218         u8 data;
 219
 220         client = (struct i2c_client *)TPM_VPRIV(chip);
 221
 222         data = TPM_STS_COMMAND_READY;
 223         I2C_WRITE_DATA(client, TPM_STS, &data, 1);
 224         if (chip->vendor.irq)
 225                 wait_for_serirq_timeout(chip, 1, chip->vendor.timeout_a);
 226 }       /* tpm_stm_i2c_cancel() */
 227
 228 /*
 229  * tpm_stm_spi_status return the TPM_STS register
 230  * @param: chip, the tpm chip description
 231  * @return: the TPM_STS register value.
 232  */
 233 static u8 tpm_stm_i2c_status(struct tpm_chip *chip)
 234 {
 235         struct i2c_client *client;
 236         u8 data;
 237         client = (struct i2c_client *)TPM_VPRIV(chip);
 238
 239         I2C_READ_DATA(client, TPM_STS, &data, 1);
 240         return data;
 241 }                               /* tpm_stm_i2c_status() */
 242
 243
 244 /*
 245  * check_locality if the locality is active
 246  * @param: chip, the tpm chip description
 247  * @return: the active locality or -EACCESS.
 248  */
 249 static int check_locality(struct tpm_chip *chip)
 250 {
 251         struct i2c_client *client;
 252         u8 data;
 253         u8 status;
 254
 255         client = (struct i2c_client *)TPM_VPRIV(chip);
 256
 257         status = I2C_READ_DATA(client, TPM_ACCESS, &data, 1);
 258         if (status && (data &
 259                 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
 260                 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
 261                 return chip->vendor.locality;
 262
 263         return -EACCES;
 264
 265 } /* check_locality() */
 266
 267 /*
 268  * request_locality request the TPM locality
 269  * @param: chip, the chip description
 270  * @return: the active locality or EACCESS.
 271  */
 272 static int request_locality(struct tpm_chip *chip)
 273 {
 274         unsigned long stop;
 275         long rc;
 276         struct i2c_client *client;
 277         u8 data;
 278
 279         client = (struct i2c_client *)TPM_VPRIV(chip);
 280
 281         if (check_locality(chip) == chip->vendor.locality)
 282                 return chip->vendor.locality;
 283
 284         data = TPM_ACCESS_REQUEST_USE;
 285         rc = I2C_WRITE_DATA(client, TPM_ACCESS, &data, 1);
 286         if (rc < 0)
 287                 goto end;
 288
 289         if (chip->vendor.irq) {
 290                 rc = wait_for_serirq_timeout(chip, (check_locality
 291                                                        (chip) >= 0),
 292                                                       chip->vendor.timeout_a);
 293                 if (rc > 0)
 294                         return chip->vendor.locality;
 295         } else {
 296                 stop = jiffies + chip->vendor.timeout_a;
 297                 do {
 298                         if (check_locality(chip) >= 0)
 299                                 return chip->vendor.locality;
 300                         msleep(TPM_TIMEOUT);
 301                 } while (time_before(jiffies, stop));
 302         }
 303         rc = -EACCES;
 304 end:
 305         return rc;
 306 } /* request_locality() */
 307
 308 /*
 309  * release_locality release the active locality
 310  * @param: chip, the tpm chip description.
 311  */
 312 static void release_locality(struct tpm_chip *chip)
 313 {
 314         struct i2c_client *client;
 315         u8 data;
 316
 317         client = (struct i2c_client *)TPM_VPRIV(chip);
 318         data = TPM_ACCESS_ACTIVE_LOCALITY;
 319
 320         I2C_WRITE_DATA(client, TPM_ACCESS, &data, 1);
 321 }
 322
 323 /*
 324  * get_burstcount return the burstcount address 0x19 0x1A
 325  * @param: chip, the chip description
 326  * return: the burstcount.
 327  */
 328 static int get_burstcount(struct tpm_chip *chip)
 329 {
 330         unsigned long stop;
 331         int burstcnt, status;
 332         u8 tpm_reg, temp;
 333
 334         struct i2c_client *client = (struct i2c_client *)TPM_VPRIV(chip);
 335
 336         stop = jiffies + chip->vendor.timeout_d;
 337         do {
 338                 tpm_reg = TPM_STS + 1;
 339                 status = I2C_READ_DATA(client, tpm_reg, &temp, 1);
 340                 if (status < 0)
 341                         goto end;
 342
 343                 tpm_reg = tpm_reg + 1;
 344                 burstcnt = temp;
 345                 status = I2C_READ_DATA(client, tpm_reg, &temp, 1);
 346                 if (status < 0)
 347                         goto end;
 348
 349                 burstcnt |= temp << 8;
 350                 if (burstcnt)
 351                         return burstcnt;
 352                 msleep(TPM_TIMEOUT);
 353         } while (time_before(jiffies, stop));
 354
 355 end:
 356         return -EBUSY;
 357 } /* get_burstcount() */
 358
 359 /*
 360  * wait_for_stat wait for a TPM_STS value
 361  * @param: chip, the tpm chip description
 362  * @param: mask, the value mask to wait
 363  * @param: timeout, the timeout
 364  * @param: queue, the wait queue.
 365  * @return: the tpm status, 0 if success, -ETIME if timeout is reached.
 366  */
 367 static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
 368                          wait_queue_head_t *queue)
 369 {
 370         unsigned long stop;
 371         long rc;
 372         u8 status;
 373
 374          if (chip->vendor.irq) {
 375                 rc = wait_for_serirq_timeout(chip, ((tpm_stm_i2c_status
 376                                                         (chip) & mask) ==
 377                                                        mask), timeout);
 378                 if (rc > 0)
 379                         return 0;
 380         } else {
 381                 stop = jiffies + timeout;
 382                 do {
 383                         msleep(TPM_TIMEOUT);
 384                         status = tpm_stm_i2c_status(chip);
 385                         if ((status & mask) == mask)
 386                                 return 0;
 387                 } while (time_before(jiffies, stop));
 388         }
 389         return -ETIME;
 390 } /* wait_for_stat() */
 391
 392 /*
 393  * recv_data receive data
 394  * @param: chip, the tpm chip description
 395  * @param: buf, the buffer where the data are received
 396  * @param: count, the number of data to receive
 397  * @return: the number of bytes read from TPM FIFO.
 398  */
 399 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 400 {
 401         int size = 0, burstcnt, len;
 402         struct i2c_client *client;
 403
 404         client = (struct i2c_client *)TPM_VPRIV(chip);
 405
 406         while (size < count &&
 407                wait_for_stat(chip,
 408                              TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 409                              chip->vendor.timeout_c,
 410                              &chip->vendor.read_queue)
 411                == 0) {
 412                 burstcnt = get_burstcount(chip);
 413                 if (burstcnt < 0)
 414                         return burstcnt;
 415                 len = min_t(int, burstcnt, count - size);
 416                 I2C_READ_DATA(client, TPM_DATA_FIFO, buf + size, len);
 417                 size += len;
 418         }
 419         return size;
 420 }
 421
 422 /*
 423  * tpm_ioserirq_handler the serirq irq handler
 424  * @param: irq, the tpm chip description
 425  * @param: dev_id, the description of the chip
 426  * @return: the status of the handler.
 427  */
 428 static irqreturn_t tpm_ioserirq_handler(int irq, void *dev_id)
 429 {
 430         struct tpm_chip *chip = dev_id;
 431         struct i2c_client *client;
 432         struct st33zp24_platform_data *pin_infos;
 433
 434         disable_irq_nosync(irq);
 435
 436         client = (struct i2c_client *)TPM_VPRIV(chip);
 437         pin_infos = client->dev.platform_data;
 438
 439         complete(&pin_infos->irq_detection);
 440         return IRQ_HANDLED;
 441 } /* tpm_ioserirq_handler() */
 442
 443
 444 /*
 445  * tpm_stm_i2c_send send TPM commands through the I2C bus.
 446  *
 447  * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
 448  * @param: buf, the buffer to send.
 449  * @param: count, the number of bytes to send.
 450  * @return: In case of success the number of bytes sent.
 451  *                      In other case, a < 0 value describing the issue.
 452  */
 453 static int tpm_stm_i2c_send(struct tpm_chip *chip, unsigned char *buf,
 454                             size_t len)
 455 {
 456         u32 status, i, size;
 457         int burstcnt = 0;
 458         int ret;
 459         u8 data;
 460         struct i2c_client *client;
 461
 462         if (chip == NULL)
 463                 return -EBUSY;
 464         if (len < TPM_HEADER_SIZE)
 465                 return -EBUSY;
 466
 467         client = (struct i2c_client *)TPM_VPRIV(chip);
 468
 469         client->flags = 0;
 470
 471         ret = request_locality(chip);
 472         if (ret < 0)
 473                 return ret;
 474
 475         status = tpm_stm_i2c_status(chip);
 476         if ((status & TPM_STS_COMMAND_READY) == 0) {
 477                 tpm_stm_i2c_cancel(chip);
 478                 if (wait_for_stat
 479                     (chip, TPM_STS_COMMAND_READY, chip->vendor.timeout_b,
 480                      &chip->vendor.int_queue) < 0) {
 481                         ret = -ETIME;
 482                         goto out_err;
 483                 }
 484         }
 485
 486         for (i = 0; i < len - 1;) {
 487                 burstcnt = get_burstcount(chip);
 488                 if (burstcnt < 0)
 489                         return burstcnt;
 490                 size = min_t(int, len - i - 1, burstcnt);
 491                 ret = I2C_WRITE_DATA(client, TPM_DATA_FIFO, buf, size);
 492                 if (ret < 0)
 493                         goto out_err;
 494
 495                 i += size;
 496         }
 497
 498         status = tpm_stm_i2c_status(chip);
 499         if ((status & TPM_STS_DATA_EXPECT) == 0) {
 500                 ret = -EIO;
 501                 goto out_err;
 502         }
 503
 504         ret = I2C_WRITE_DATA(client, TPM_DATA_FIFO, buf + len - 1, 1);
 505         if (ret < 0)
 506                 goto out_err;
 507
 508         status = tpm_stm_i2c_status(chip);
 509         if ((status & TPM_STS_DATA_EXPECT) != 0) {
 510                 ret = -EIO;
 511                 goto out_err;
 512         }
 513
 514         data = TPM_STS_GO;
 515         I2C_WRITE_DATA(client, TPM_STS, &data, 1);
 516
 517         return len;
 518 out_err:
 519         tpm_stm_i2c_cancel(chip);
 520         release_locality(chip);
 521         return ret;
 522 }
 523
 524 /*
 525  * tpm_stm_i2c_recv received TPM response through the I2C bus.
 526  * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
 527  * @param: buf, the buffer to store datas.
 528  * @param: count, the number of bytes to send.
 529  * @return: In case of success the number of bytes received.
 530  *              In other case, a < 0 value describing the issue.
 531  */
 532 static int tpm_stm_i2c_recv(struct tpm_chip *chip, unsigned char *buf,
 533                             size_t count)
 534 {
 535         int size = 0;
 536         int expected;
 537
 538         if (chip == NULL)
 539                 return -EBUSY;
 540
 541         if (count < TPM_HEADER_SIZE) {
 542                 size = -EIO;
 543                 goto out;
 544         }
 545
 546         size = recv_data(chip, buf, TPM_HEADER_SIZE);
 547         if (size < TPM_HEADER_SIZE) {
 548                 dev_err(chip->dev, "Unable to read header\n");
 549                 goto out;
 550         }
 551
 552         expected = be32_to_cpu(*(__be32 *)(buf + 2));
 553         if (expected > count) {
 554                 size = -EIO;
 555                 goto out;
 556         }
 557
 558         size += recv_data(chip, &buf[TPM_HEADER_SIZE],
 559                                         expected - TPM_HEADER_SIZE);
 560         if (size < expected) {
 561                 dev_err(chip->dev, "Unable to read remainder of result\n");
 562                 size = -ETIME;
 563                 goto out;
 564         }
 565
 566 out:
 567         chip->vendor.cancel(chip);
 568         release_locality(chip);
 569         return size;
 570 }
 571
 572 static bool tpm_st33_i2c_req_canceled(struct tpm_chip *chip, u8 status)
 573 {
 574         return (status == TPM_STS_COMMAND_READY);
 575 }
 576
 577 static const struct file_operations tpm_st33_i2c_fops = {
 578         .owner = THIS_MODULE,
 579         .llseek = no_llseek,
 580         .read = tpm_read,
 581         .write = tpm_write,
 582         .open = tpm_open,
 583         .release = tpm_release,
 584 };
 585
 586 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
 587 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
 588 static DEVICE_ATTR(enabled, S_IRUGO, tpm_show_enabled, NULL);
 589 static DEVICE_ATTR(active, S_IRUGO, tpm_show_active, NULL);
 590 static DEVICE_ATTR(owned, S_IRUGO, tpm_show_owned, NULL);
 591 static DEVICE_ATTR(temp_deactivated, S_IRUGO, tpm_show_temp_deactivated, NULL);
 592 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps, NULL);
 593 static DEVICE_ATTR(cancel, S_IWUSR | S_IWGRP, NULL, tpm_store_cancel);
 594
 595 static struct attribute *stm_tpm_attrs[] = {
 596         &dev_attr_pubek.attr,
 597         &dev_attr_pcrs.attr,
 598         &dev_attr_enabled.attr,
 599         &dev_attr_active.attr,
 600         &dev_attr_owned.attr,
 601         &dev_attr_temp_deactivated.attr,
 602         &dev_attr_caps.attr,
 603         &dev_attr_cancel.attr, NULL,
 604 };
 605
 606 static struct attribute_group stm_tpm_attr_grp = {
 607         .attrs = stm_tpm_attrs
 608 };
 609
 610 static struct tpm_vendor_specific st_i2c_tpm = {
 611         .send = tpm_stm_i2c_send,
 612         .recv = tpm_stm_i2c_recv,
 613         .cancel = tpm_stm_i2c_cancel,
 614         .status = tpm_stm_i2c_status,
 615         .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 616         .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 617         .req_canceled = tpm_st33_i2c_req_canceled,
 618         .attr_group = &stm_tpm_attr_grp,
 619         .miscdev = {.fops = &tpm_st33_i2c_fops,},
 620 };
 621
 622 static int interrupts;
 623 module_param(interrupts, int, 0444);
 624 MODULE_PARM_DESC(interrupts, "Enable interrupts");
 625
 626 static int power_mgt = 1;
 627 module_param(power_mgt, int, 0444);
 628 MODULE_PARM_DESC(power_mgt, "Power Management");
 629
 630 /*
 631  * tpm_st33_i2c_probe initialize the TPM device
 632  * @param: client, the i2c_client drescription (TPM I2C description).
 633  * @param: id, the i2c_device_id struct.
 634  * @return: 0 in case of success.
 635  *       -1 in other case.
 636  */
 637 static int
 638 tpm_st33_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id)
 639 {
 640         int err;
 641         u8 intmask;
 642         struct tpm_chip *chip;
 643         struct st33zp24_platform_data *platform_data;
 644
 645         if (client == NULL) {
 646                 pr_info("%s: i2c client is NULL. Device not accessible.\n",
 647                         __func__);
 648                 err = -ENODEV;
 649                 goto end;
 650         }
 651
 652         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 653                 dev_info(&client->dev, "client not i2c capable\n");
 654                 err = -ENODEV;
 655                 goto end;
 656         }
 657
 658         chip = tpm_register_hardware(&client->dev, &st_i2c_tpm);
 659         if (!chip) {
 660                 dev_info(&client->dev, "fail chip\n");
 661                 err = -ENODEV;
 662                 goto end;
 663         }
 664
 665         platform_data = client->dev.platform_data;
 666
 667         if (!platform_data) {
 668                 dev_info(&client->dev, "chip not available\n");
 669                 err = -ENODEV;
 670                 goto _tpm_clean_answer;
 671         }
 672
 673         platform_data->tpm_i2c_buffer[0] =
 674             kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 675         if (platform_data->tpm_i2c_buffer[0] == NULL) {
 676                 err = -ENOMEM;
 677                 goto _tpm_clean_answer;
 678         }
 679         platform_data->tpm_i2c_buffer[1] =
 680             kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 681         if (platform_data->tpm_i2c_buffer[1] == NULL) {
 682                 err = -ENOMEM;
 683                 goto _tpm_clean_response1;
 684         }
 685
 686         TPM_VPRIV(chip) = client;
 687
 688         chip->vendor.timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
 689         chip->vendor.timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
 690         chip->vendor.timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
 691         chip->vendor.timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
 692
 693         chip->vendor.locality = LOCALITY0;
 694
 695         if (power_mgt) {
 696                 err = gpio_request(platform_data->io_lpcpd, "TPM IO_LPCPD");
 697                 if (err)
 698                         goto _gpio_init1;
 699                 gpio_set_value(platform_data->io_lpcpd, 1);
 700         }
 701
 702         if (interrupts) {
 703                 init_completion(&platform_data->irq_detection);
 704                 if (request_locality(chip) != LOCALITY0) {
 705                         err = -ENODEV;
 706                         goto _tpm_clean_response2;
 707                 }
 708                 err = gpio_request(platform_data->io_serirq, "TPM IO_SERIRQ");
 709                 if (err)
 710                         goto _gpio_init2;
 711
 712                 clear_interruption(client);
 713                 err = request_irq(gpio_to_irq(platform_data->io_serirq),
 714                                 &tpm_ioserirq_handler,
 715                                 IRQF_TRIGGER_HIGH,
 716                                 "TPM SERIRQ management", chip);
 717                 if (err < 0) {
 718                         dev_err(chip->dev , "TPM SERIRQ signals %d not available\n",
 719                                 gpio_to_irq(platform_data->io_serirq));
 720                         goto _irq_set;
 721                 }
 722
 723                 err = I2C_READ_DATA(client, TPM_INT_ENABLE, &intmask, 1);
 724                 if (err < 0)
 725                         goto _irq_set;
 726
 727                 intmask |= TPM_INTF_CMD_READY_INT
 728                         |  TPM_INTF_FIFO_AVALAIBLE_INT
 729                         |  TPM_INTF_WAKE_UP_READY_INT
 730                         |  TPM_INTF_LOCALITY_CHANGE_INT
 731                         |  TPM_INTF_STS_VALID_INT
 732                         |  TPM_INTF_DATA_AVAIL_INT;
 733
 734                 err = I2C_WRITE_DATA(client, TPM_INT_ENABLE, &intmask, 1);
 735                 if (err < 0)
 736                         goto _irq_set;
 737
 738                 intmask = TPM_GLOBAL_INT_ENABLE;
 739                 err = I2C_WRITE_DATA(client, (TPM_INT_ENABLE + 3), &intmask, 1);
 740                 if (err < 0)
 741                         goto _irq_set;
 742
 743                 err = I2C_READ_DATA(client, TPM_INT_STATUS, &intmask, 1);
 744                 if (err < 0)
 745                         goto _irq_set;
 746
 747                 chip->vendor.irq = interrupts;
 748
 749                 tpm_gen_interrupt(chip);
 750         }
 751
 752         tpm_get_timeouts(chip);
 753
 754         dev_info(chip->dev, "TPM I2C Initialized\n");
 755         return 0;
 756 _irq_set:
 757         free_irq(gpio_to_irq(platform_data->io_serirq), (void *)chip);
 758 _gpio_init2:
 759         if (interrupts)
 760                 gpio_free(platform_data->io_serirq);
 761 _gpio_init1:
 762         if (power_mgt)
 763                 gpio_free(platform_data->io_lpcpd);
 764 _tpm_clean_response2:
 765         kzfree(platform_data->tpm_i2c_buffer[1]);
 766         platform_data->tpm_i2c_buffer[1] = NULL;
 767 _tpm_clean_response1:
 768         kzfree(platform_data->tpm_i2c_buffer[0]);
 769         platform_data->tpm_i2c_buffer[0] = NULL;
 770 _tpm_clean_answer:
 771         tpm_remove_hardware(chip->dev);
 772 end:
 773         pr_info("TPM I2C initialisation fail\n");
 774         return err;
 775 }
 776
 777 /*
 778  * tpm_st33_i2c_remove remove the TPM device
 779  * @param: client, the i2c_client drescription (TPM I2C description).
 780                 clear_bit(0, &chip->is_open);
 781  * @return: 0 in case of success.
 782  */
 783 static int tpm_st33_i2c_remove(struct i2c_client *client)
 784 {
 785         struct tpm_chip *chip = (struct tpm_chip *)i2c_get_clientdata(client);
 786         struct st33zp24_platform_data *pin_infos =
 787                 ((struct i2c_client *)TPM_VPRIV(chip))->dev.platform_data;
 788
 789         if (pin_infos != NULL) {
 790                 free_irq(pin_infos->io_serirq, chip);
 791
 792                 gpio_free(pin_infos->io_serirq);
 793                 gpio_free(pin_infos->io_lpcpd);
 794
 795                 tpm_remove_hardware(chip->dev);
 796
 797                 if (pin_infos->tpm_i2c_buffer[1] != NULL) {
 798                         kzfree(pin_infos->tpm_i2c_buffer[1]);
 799                         pin_infos->tpm_i2c_buffer[1] = NULL;
 800                 }
 801                 if (pin_infos->tpm_i2c_buffer[0] != NULL) {
 802                         kzfree(pin_infos->tpm_i2c_buffer[0]);
 803                         pin_infos->tpm_i2c_buffer[0] = NULL;
 804                 }
 805         }
 806
 807         return 0;
 808 }
 809
 810 #ifdef CONFIG_PM_SLEEP
 811 /*
 812  * tpm_st33_i2c_pm_suspend suspend the TPM device
 813  * @param: client, the i2c_client drescription (TPM I2C description).
 814  * @param: mesg, the power management message.
 815  * @return: 0 in case of success.
 816  */
 817 static int tpm_st33_i2c_pm_suspend(struct device *dev)
 818 {
 819         struct st33zp24_platform_data *pin_infos = dev->platform_data;
 820         int ret = 0;
 821
 822         if (power_mgt) {
 823                 gpio_set_value(pin_infos->io_lpcpd, 0);
 824         } else {
 825                 ret = tpm_pm_suspend(dev);
 826         }
 827         return ret;
 828 }                               /* tpm_st33_i2c_suspend() */
 829
 830 /*
 831  * tpm_st33_i2c_pm_resume resume the TPM device
 832  * @param: client, the i2c_client drescription (TPM I2C description).
 833  * @return: 0 in case of success.
 834  */
 835 static int tpm_st33_i2c_pm_resume(struct device *dev)
 836 {
 837         struct tpm_chip *chip = dev_get_drvdata(dev);
 838         struct st33zp24_platform_data *pin_infos = dev->platform_data;
 839
 840         int ret = 0;
 841
 842         if (power_mgt) {
 843                 gpio_set_value(pin_infos->io_lpcpd, 1);
 844                 ret = wait_for_serirq_timeout(chip,
 845                                           (chip->vendor.status(chip) &
 846                                           TPM_STS_VALID) == TPM_STS_VALID,
 847                                           chip->vendor.timeout_b);
 848         } else {
 849                 ret = tpm_pm_resume(dev);
 850                 if (!ret)
 851                         tpm_do_selftest(chip);
 852         }
 853         return ret;
 854 }                               /* tpm_st33_i2c_pm_resume() */
 855 #endif
 856
 857 static const struct i2c_device_id tpm_st33_i2c_id[] = {
 858         {TPM_ST33_I2C, 0},
 859         {}
 860 };
 861 MODULE_DEVICE_TABLE(i2c, tpm_st33_i2c_id);
 862 static SIMPLE_DEV_PM_OPS(tpm_st33_i2c_ops, tpm_st33_i2c_pm_suspend,
 863         tpm_st33_i2c_pm_resume);
 864 static struct i2c_driver tpm_st33_i2c_driver = {
 865         .driver = {
 866                    .owner = THIS_MODULE,
 867                    .name = TPM_ST33_I2C,
 868                    .pm = &tpm_st33_i2c_ops,
 869                    },
 870         .probe = tpm_st33_i2c_probe,
 871         .remove = tpm_st33_i2c_remove,
 872         .id_table = tpm_st33_i2c_id
 873 };
 874
 875 module_i2c_driver(tpm_st33_i2c_driver);
 876
 877 MODULE_AUTHOR("Christophe Ricard (tpmsupport@st.com)");
 878 MODULE_DESCRIPTION("STM TPM I2C ST33 Driver");
 879 MODULE_VERSION("1.2.0");
 880 MODULE_LICENSE("GPL");