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/module.h>
  40 #include <linux/kernel.h>
  41 #include <linux/delay.h>
  42 #include <linux/init.h>
  43 #include <linux/wait.h>
  44 #include <linux/string.h>
  45 #include <linux/interrupt.h>
  46 #include <linux/spinlock.h>
  47 #include <linux/sysfs.h>
  48 #include <linux/gpio.h>
  49 #include <linux/sched.h>
  50 #include <linux/uaccess.h>
  51 #include <linux/io.h>
  52 #include <linux/slab.h>
  53 #include <linux/sched.h>
  54
  55 #include "tpm.h"
  56 #include "tpm_i2c_stm_st33.h"
  57
  58 enum stm33zp24_access {
  59         TPM_ACCESS_VALID = 0x80,
  60         TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
  61         TPM_ACCESS_REQUEST_PENDING = 0x04,
  62         TPM_ACCESS_REQUEST_USE = 0x02,
  63 };
  64
  65 enum stm33zp24_status {
  66         TPM_STS_VALID = 0x80,
  67         TPM_STS_COMMAND_READY = 0x40,
  68         TPM_STS_GO = 0x20,
  69         TPM_STS_DATA_AVAIL = 0x10,
  70         TPM_STS_DATA_EXPECT = 0x08,
  71 };
  72
  73 enum stm33zp24_int_flags {
  74         TPM_GLOBAL_INT_ENABLE = 0x80,
  75         TPM_INTF_CMD_READY_INT = 0x080,
  76         TPM_INTF_FIFO_AVALAIBLE_INT = 0x040,
  77         TPM_INTF_WAKE_UP_READY_INT = 0x020,
  78         TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
  79         TPM_INTF_STS_VALID_INT = 0x002,
  80         TPM_INTF_DATA_AVAIL_INT = 0x001,
  81 };
  82
  83 enum tis_defaults {
  84         TIS_SHORT_TIMEOUT = 750,
  85         TIS_LONG_TIMEOUT = 2000,
  86 };
  87
  88 /*
  89  * write8_reg
  90  * Send byte to the TIS register according to the ST33ZP24 I2C protocol.
  91  * @param: tpm_register, the tpm tis register where the data should be written
  92  * @param: tpm_data, the tpm_data to write inside the tpm_register
  93  * @param: tpm_size, The length of the data
  94  * @return: Returns negative errno, or else the number of bytes written.
  95  */
  96 static int write8_reg(struct i2c_client *client, u8 tpm_register,
  97                       u8 *tpm_data, u16 tpm_size)
  98 {
  99         struct st33zp24_platform_data *pin_infos;
 100
 101         pin_infos = client->dev.platform_data;
 102
 103         pin_infos->tpm_i2c_buffer[0][0] = tpm_register;
 104         memcpy(&pin_infos->tpm_i2c_buffer[0][1], tpm_data, tpm_size);
 105         return i2c_master_send(client, pin_infos->tpm_i2c_buffer[0],
 106                                 tpm_size + 1);
 107 } /* write8_reg() */
 108
 109 /*
 110  * read8_reg
 111  * Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
 112  * @param: tpm_register, the tpm tis register where the data should be read
 113  * @param: tpm_data, the TPM response
 114  * @param: tpm_size, tpm TPM response size to read.
 115  * @return: number of byte read successfully: should be one if success.
 116  */
 117 static int read8_reg(struct i2c_client *client, u8 tpm_register,
 118                     u8 *tpm_data, int tpm_size)
 119 {
 120         u8 status = 0;
 121         u8 data;
 122
 123         data = TPM_DUMMY_BYTE;
 124         status = write8_reg(client, tpm_register, &data, 1);
 125         if (status == 2)
 126                 status = i2c_master_recv(client, tpm_data, tpm_size);
 127         return status;
 128 } /* read8_reg() */
 129
 130 /*
 131  * I2C_WRITE_DATA
 132  * Send byte to the TIS register according to the ST33ZP24 I2C protocol.
 133  * @param: client, the chip description
 134  * @param: tpm_register, the tpm tis register where the data should be written
 135  * @param: tpm_data, the tpm_data to write inside the tpm_register
 136  * @param: tpm_size, The length of the data
 137  * @return: number of byte written successfully: should be one if success.
 138  */
 139 #define I2C_WRITE_DATA(client, tpm_register, tpm_data, tpm_size) \
 140         (write8_reg(client, tpm_register | \
 141         TPM_WRITE_DIRECTION, tpm_data, tpm_size))
 142
 143 /*
 144  * I2C_READ_DATA
 145  * Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
 146  * @param: tpm, the chip description
 147  * @param: tpm_register, the tpm tis register where the data should be read
 148  * @param: tpm_data, the TPM response
 149  * @param: tpm_size, tpm TPM response size to read.
 150  * @return: number of byte read successfully: should be one if success.
 151  */
 152 #define I2C_READ_DATA(client, tpm_register, tpm_data, tpm_size) \
 153         (read8_reg(client, tpm_register, tpm_data, tpm_size))
 154
 155 /*
 156  * clear_interruption
 157  * clear the TPM interrupt register.
 158  * @param: tpm, the chip description
 159  */
 160 static void clear_interruption(struct i2c_client *client)
 161 {
 162         u8 interrupt;
 163         I2C_READ_DATA(client, TPM_INT_STATUS, &interrupt, 1);
 164         I2C_WRITE_DATA(client, TPM_INT_STATUS, &interrupt, 1);
 165         I2C_READ_DATA(client, TPM_INT_STATUS, &interrupt, 1);
 166 } /* clear_interruption() */
 167
 168 /*
 169  * _wait_for_interrupt_serirq_timeout
 170  * @param: tpm, the chip description
 171  * @param: timeout, the timeout of the interrupt
 172  * @return: the status of the interruption.
 173  */
 174 static long _wait_for_interrupt_serirq_timeout(struct tpm_chip *chip,
 175                                                 unsigned long timeout)
 176 {
 177         long status;
 178         struct i2c_client *client;
 179         struct st33zp24_platform_data *pin_infos;
 180
 181         client = (struct i2c_client *) TPM_VPRIV(chip);
 182         pin_infos = client->dev.platform_data;
 183
 184         status = wait_for_completion_interruptible_timeout(
 185                                         &pin_infos->irq_detection,
 186                                                 timeout);
 187         if (status > 0)
 188                 enable_irq(gpio_to_irq(pin_infos->io_serirq));
 189         gpio_direction_input(pin_infos->io_serirq);
 190
 191         return status;
 192 } /* wait_for_interrupt_serirq_timeout() */
 193
 194 static int wait_for_serirq_timeout(struct tpm_chip *chip, bool condition,
 195                                  unsigned long timeout)
 196 {
 197         int status = 2;
 198         struct i2c_client *client;
 199
 200         client = (struct i2c_client *) TPM_VPRIV(chip);
 201
 202         status = _wait_for_interrupt_serirq_timeout(chip, timeout);
 203         if (!status) {
 204                 status = -EBUSY;
 205         } else{
 206                 clear_interruption(client);
 207                 if (condition)
 208                         status = 1;
 209         }
 210         return status;
 211 }
 212
 213 /*
 214  * tpm_stm_i2c_cancel, cancel is not implemented.
 215  * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
 216  */
 217 static void tpm_stm_i2c_cancel(struct tpm_chip *chip)
 218 {
 219         struct i2c_client *client;
 220         u8 data;
 221
 222         client = (struct i2c_client *) TPM_VPRIV(chip);
 223
 224         data = TPM_STS_COMMAND_READY;
 225         I2C_WRITE_DATA(client, TPM_STS, &data, 1);
 226         if (chip->vendor.irq)
 227                 wait_for_serirq_timeout(chip, 1, chip->vendor.timeout_a);
 228 }       /* tpm_stm_i2c_cancel() */
 229
 230 /*
 231  * tpm_stm_spi_status return the TPM_STS register
 232  * @param: chip, the tpm chip description
 233  * @return: the TPM_STS register value.
 234  */
 235 static u8 tpm_stm_i2c_status(struct tpm_chip *chip)
 236 {
 237         struct i2c_client *client;
 238         u8 data;
 239         client = (struct i2c_client *) TPM_VPRIV(chip);
 240
 241         I2C_READ_DATA(client, TPM_STS, &data, 1);
 242         return data;
 243 }                               /* tpm_stm_i2c_status() */
 244
 245
 246 /*
 247  * check_locality if the locality is active
 248  * @param: chip, the tpm chip description
 249  * @return: the active locality or -EACCESS.
 250  */
 251 static int check_locality(struct tpm_chip *chip)
 252 {
 253         struct i2c_client *client;
 254         u8 data;
 255         u8 status;
 256
 257         client = (struct i2c_client *) TPM_VPRIV(chip);
 258
 259         status = I2C_READ_DATA(client, TPM_ACCESS, &data, 1);
 260         if (status && (data &
 261                 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
 262                 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
 263                 return chip->vendor.locality;
 264
 265         return -EACCES;
 266
 267 } /* check_locality() */
 268
 269 /*
 270  * request_locality request the TPM locality
 271  * @param: chip, the chip description
 272  * @return: the active locality or EACCESS.
 273  */
 274 static int request_locality(struct tpm_chip *chip)
 275 {
 276         unsigned long stop;
 277         long rc;
 278         struct i2c_client *client;
 279         u8 data;
 280
 281         client = (struct i2c_client *) TPM_VPRIV(chip);
 282
 283         if (check_locality(chip) == chip->vendor.locality)
 284                 return chip->vendor.locality;
 285
 286         data = TPM_ACCESS_REQUEST_USE;
 287         rc = I2C_WRITE_DATA(client, TPM_ACCESS, &data, 1);
 288         if (rc < 0)
 289                 goto end;
 290
 291         if (chip->vendor.irq) {
 292                 rc = wait_for_serirq_timeout(chip, (check_locality
 293                                                        (chip) >= 0),
 294                                                       chip->vendor.timeout_a);
 295                 if (rc > 0)
 296                         return chip->vendor.locality;
 297         } else{
 298                 stop = jiffies + chip->vendor.timeout_a;
 299                 do {
 300                         if (check_locality(chip) >= 0)
 301                                 return chip->vendor.locality;
 302                         msleep(TPM_TIMEOUT);
 303                 } while (time_before(jiffies, stop));
 304         }
 305         rc = -EACCES;
 306 end:
 307         return rc;
 308 } /* request_locality() */
 309
 310 /*
 311  * release_locality release the active locality
 312  * @param: chip, the tpm chip description.
 313  */
 314 static void release_locality(struct tpm_chip *chip)
 315 {
 316         struct i2c_client *client;
 317         u8 data;
 318
 319         client = (struct i2c_client *) TPM_VPRIV(chip);
 320         data = TPM_ACCESS_ACTIVE_LOCALITY;
 321
 322         I2C_WRITE_DATA(client, TPM_ACCESS, &data, 1);
 323 }
 324
 325 /*
 326  * get_burstcount return the burstcount address 0x19 0x1A
 327  * @param: chip, the chip description
 328  * return: the burstcount.
 329  */
 330 static int get_burstcount(struct tpm_chip *chip)
 331 {
 332         unsigned long stop;
 333         int burstcnt, status;
 334         u8 tpm_reg, temp;
 335
 336         struct i2c_client *client = (struct i2c_client *) TPM_VPRIV(chip);
 337
 338         stop = jiffies + chip->vendor.timeout_d;
 339         do {
 340                 tpm_reg = TPM_STS + 1;
 341                 status = I2C_READ_DATA(client, tpm_reg, &temp, 1);
 342                 if (status < 0)
 343                         goto end;
 344
 345                 tpm_reg = tpm_reg + 1;
 346                 burstcnt = temp;
 347                 status = I2C_READ_DATA(client, tpm_reg, &temp, 1);
 348                 if (status < 0)
 349                         goto end;
 350
 351                 burstcnt |= temp << 8;
 352                 if (burstcnt)
 353                         return burstcnt;
 354                 msleep(TPM_TIMEOUT);
 355         } while (time_before(jiffies, stop));
 356
 357 end:
 358         return -EBUSY;
 359 } /* get_burstcount() */
 360
 361 /*
 362  * wait_for_stat wait for a TPM_STS value
 363  * @param: chip, the tpm chip description
 364  * @param: mask, the value mask to wait
 365  * @param: timeout, the timeout
 366  * @param: queue, the wait queue.
 367  * @return: the tpm status, 0 if success, -ETIME if timeout is reached.
 368  */
 369 static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
 370                          wait_queue_head_t *queue)
 371 {
 372         unsigned long stop;
 373         long rc;
 374         u8 status;
 375
 376          if (chip->vendor.irq) {
 377                 rc = wait_for_serirq_timeout(chip, ((tpm_stm_i2c_status
 378                                                         (chip) & mask) ==
 379                                                        mask), timeout);
 380                 if (rc > 0)
 381                         return 0;
 382         } else{
 383                 stop = jiffies + timeout;
 384                 do {
 385                         msleep(TPM_TIMEOUT);
 386                         status = tpm_stm_i2c_status(chip);
 387                         if ((status & mask) == mask)
 388                                 return 0;
 389                 } while (time_before(jiffies, stop));
 390         }
 391         return -ETIME;
 392 } /* wait_for_stat() */
 393
 394 /*
 395  * recv_data receive data
 396  * @param: chip, the tpm chip description
 397  * @param: buf, the buffer where the data are received
 398  * @param: count, the number of data to receive
 399  * @return: the number of bytes read from TPM FIFO.
 400  */
 401 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 402 {
 403         int size = 0, burstcnt, len;
 404         struct i2c_client *client;
 405
 406         client = (struct i2c_client *) TPM_VPRIV(chip);
 407
 408         while (size < count &&
 409                wait_for_stat(chip,
 410                              TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 411                              chip->vendor.timeout_c,
 412                              &chip->vendor.read_queue)
 413                == 0) {
 414                 burstcnt = get_burstcount(chip);
 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,
 457             burstcnt = 0, i, size;
 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                 size = min_t(int, len - i - 1, burstcnt);
 489                 ret = I2C_WRITE_DATA(client, TPM_DATA_FIFO, buf, size);
 490                 if (ret < 0)
 491                         goto out_err;
 492
 493                 i += size;
 494         }
 495
 496         status = tpm_stm_i2c_status(chip);
 497         if ((status & TPM_STS_DATA_EXPECT) == 0) {
 498                 ret = -EIO;
 499                 goto out_err;
 500         }
 501
 502         ret = I2C_WRITE_DATA(client, TPM_DATA_FIFO, buf + len - 1, 1);
 503         if (ret < 0)
 504                 goto out_err;
 505
 506         status = tpm_stm_i2c_status(chip);
 507         if ((status & TPM_STS_DATA_EXPECT) != 0) {
 508                 ret = -EIO;
 509                 goto out_err;
 510         }
 511
 512         data = TPM_STS_GO;
 513         I2C_WRITE_DATA(client, TPM_STS, &data, 1);
 514
 515         return len;
 516 out_err:
 517         tpm_stm_i2c_cancel(chip);
 518         release_locality(chip);
 519         return ret;
 520 }
 521
 522 /*
 523  * tpm_stm_i2c_recv received TPM response through the I2C bus.
 524  * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
 525  * @param: buf, the buffer to store datas.
 526  * @param: count, the number of bytes to send.
 527  * @return: In case of success the number of bytes received.
 528  *              In other case, a < 0 value describing the issue.
 529  */
 530 static int tpm_stm_i2c_recv(struct tpm_chip *chip, unsigned char *buf,
 531                             size_t count)
 532 {
 533         int size = 0;
 534         int expected;
 535
 536         if (chip == NULL)
 537                 return -EBUSY;
 538
 539         if (count < TPM_HEADER_SIZE) {
 540                 size = -EIO;
 541                 goto out;
 542         }
 543
 544         size = recv_data(chip, buf, TPM_HEADER_SIZE);
 545         if (size < TPM_HEADER_SIZE) {
 546                 dev_err(chip->dev, "Unable to read header\n");
 547                 goto out;
 548         }
 549
 550         expected = be32_to_cpu(*(__be32 *) (buf + 2));
 551         if (expected > count) {
 552                 size = -EIO;
 553                 goto out;
 554         }
 555
 556         size += recv_data(chip, &buf[TPM_HEADER_SIZE],
 557                                         expected - TPM_HEADER_SIZE);
 558         if (size < expected) {
 559                 dev_err(chip->dev, "Unable to read remainder of result\n");
 560                 size = -ETIME;
 561                 goto out;
 562         }
 563
 564 out:
 565         chip->vendor.cancel(chip);
 566         release_locality(chip);
 567         return size;
 568 }
 569
 570 static bool tpm_st33_i2c_req_canceled(struct tpm_chip *chip, u8 status)
 571 {
 572        return (status == TPM_STS_COMMAND_READY);
 573 }
 574
 575 static const struct file_operations tpm_st33_i2c_fops = {
 576         .owner = THIS_MODULE,
 577         .llseek = no_llseek,
 578         .read = tpm_read,
 579         .write = tpm_write,
 580         .open = tpm_open,
 581         .release = tpm_release,
 582 };
 583
 584 static DEVICE_ATTR(pubek, S_IRUGO, tpm_show_pubek, NULL);
 585 static DEVICE_ATTR(pcrs, S_IRUGO, tpm_show_pcrs, NULL);
 586 static DEVICE_ATTR(enabled, S_IRUGO, tpm_show_enabled, NULL);
 587 static DEVICE_ATTR(active, S_IRUGO, tpm_show_active, NULL);
 588 static DEVICE_ATTR(owned, S_IRUGO, tpm_show_owned, NULL);
 589 static DEVICE_ATTR(temp_deactivated, S_IRUGO, tpm_show_temp_deactivated, NULL);
 590 static DEVICE_ATTR(caps, S_IRUGO, tpm_show_caps_1_2, NULL);
 591 static DEVICE_ATTR(cancel, S_IWUSR | S_IWGRP, NULL, tpm_store_cancel);
 592
 593 static struct attribute *stm_tpm_attrs[] = {
 594         &dev_attr_pubek.attr,
 595         &dev_attr_pcrs.attr,
 596         &dev_attr_enabled.attr,
 597         &dev_attr_active.attr,
 598         &dev_attr_owned.attr,
 599         &dev_attr_temp_deactivated.attr,
 600         &dev_attr_caps.attr,
 601         &dev_attr_cancel.attr, NULL,
 602 };
 603
 604 static struct attribute_group stm_tpm_attr_grp = {
 605         .attrs = stm_tpm_attrs
 606 };
 607
 608 static struct tpm_vendor_specific st_i2c_tpm = {
 609         .send = tpm_stm_i2c_send,
 610         .recv = tpm_stm_i2c_recv,
 611         .cancel = tpm_stm_i2c_cancel,
 612         .status = tpm_stm_i2c_status,
 613         .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 614         .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 615         .req_canceled = tpm_st33_i2c_req_canceled,
 616         .attr_group = &stm_tpm_attr_grp,
 617         .miscdev = {.fops = &tpm_st33_i2c_fops,},
 618 };
 619
 620 static int interrupts ;
 621 module_param(interrupts, int, 0444);
 622 MODULE_PARM_DESC(interrupts, "Enable interrupts");
 623
 624 static int power_mgt = 1;
 625 module_param(power_mgt, int, 0444);
 626 MODULE_PARM_DESC(power_mgt, "Power Management");
 627
 628 /*
 629  * tpm_st33_i2c_probe initialize the TPM device
 630  * @param: client, the i2c_client drescription (TPM I2C description).
 631  * @param: id, the i2c_device_id struct.
 632  * @return: 0 in case of success.
 633  *       -1 in other case.
 634  */
 635 static int
 636 tpm_st33_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id)
 637 {
 638         int err;
 639         u8 intmask;
 640         struct tpm_chip *chip;
 641         struct st33zp24_platform_data *platform_data;
 642
 643         if (client == NULL) {
 644                 pr_info("%s: i2c client is NULL. Device not accessible.\n",
 645                         __func__);
 646                 err = -ENODEV;
 647                 goto end;
 648         }
 649
 650         if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
 651                 dev_info(&client->dev, "client not i2c capable\n");
 652                 err = -ENODEV;
 653                 goto end;
 654         }
 655
 656         chip = tpm_register_hardware(&client->dev, &st_i2c_tpm);
 657         if (!chip) {
 658                 dev_info(&client->dev, "fail chip\n");
 659                 err = -ENODEV;
 660                 goto end;
 661         }
 662
 663         platform_data = client->dev.platform_data;
 664
 665         if (!platform_data) {
 666                 dev_info(&client->dev, "chip not available\n");
 667                 err = -ENODEV;
 668                 goto _tpm_clean_answer;
 669         }
 670
 671         platform_data->tpm_i2c_buffer[0] =
 672             kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 673         if (platform_data->tpm_i2c_buffer[0] == NULL) {
 674                 err = -ENOMEM;
 675                 goto _tpm_clean_answer;
 676         }
 677         platform_data->tpm_i2c_buffer[1] =
 678             kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
 679         if (platform_data->tpm_i2c_buffer[1] == NULL) {
 680                 err = -ENOMEM;
 681                 goto _tpm_clean_response1;
 682         }
 683
 684         TPM_VPRIV(chip) = client;
 685
 686         chip->vendor.timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
 687         chip->vendor.timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
 688         chip->vendor.timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
 689         chip->vendor.timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
 690
 691         chip->vendor.locality = LOCALITY0;
 692
 693         if (power_mgt) {
 694                 err = gpio_request(platform_data->io_lpcpd, "TPM IO_LPCPD");
 695                 if (err)
 696                         goto _gpio_init1;
 697                 gpio_set_value(platform_data->io_lpcpd, 1);
 698         }
 699
 700         if (interrupts) {
 701                 init_completion(&platform_data->irq_detection);
 702                 if (request_locality(chip) != LOCALITY0) {
 703                         err = -ENODEV;
 704                         goto _tpm_clean_response2;
 705                 }
 706                 err = gpio_request(platform_data->io_serirq, "TPM IO_SERIRQ");
 707                 if (err)
 708                         goto _gpio_init2;
 709
 710                 clear_interruption(client);
 711                 err = request_irq(gpio_to_irq(platform_data->io_serirq),
 712                                 &tpm_ioserirq_handler,
 713                                 IRQF_TRIGGER_HIGH,
 714                                 "TPM SERIRQ management", chip);
 715                 if (err < 0) {
 716                         dev_err(chip->dev , "TPM SERIRQ signals %d not available\n",
 717                         gpio_to_irq(platform_data->io_serirq));
 718                         goto _irq_set;
 719                 }
 720
 721                 err = I2C_READ_DATA(client, TPM_INT_ENABLE, &intmask, 1);
 722                 if (err < 0)
 723                         goto _irq_set;
 724
 725                 intmask |= TPM_INTF_CMD_READY_INT
 726                         |  TPM_INTF_FIFO_AVALAIBLE_INT
 727                         |  TPM_INTF_WAKE_UP_READY_INT
 728                         |  TPM_INTF_LOCALITY_CHANGE_INT
 729                         |  TPM_INTF_STS_VALID_INT
 730                         |  TPM_INTF_DATA_AVAIL_INT;
 731
 732                 err = I2C_WRITE_DATA(client, TPM_INT_ENABLE, &intmask, 1);
 733                 if (err < 0)
 734                         goto _irq_set;
 735
 736                 intmask = TPM_GLOBAL_INT_ENABLE;
 737                 err = I2C_WRITE_DATA(client, (TPM_INT_ENABLE + 3), &intmask, 1);
 738                 if (err < 0)
 739                         goto _irq_set;
 740
 741                 err = I2C_READ_DATA(client, TPM_INT_STATUS, &intmask, 1);
 742                 if (err < 0)
 743                         goto _irq_set;
 744
 745                 chip->vendor.irq = interrupts;
 746
 747                 tpm_gen_interrupt(chip);
 748         }
 749
 750         tpm_get_timeouts(chip);
 751
 752         i2c_set_clientdata(client, 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  * Added: Work around when suspend and no tpm application is running, suspend
 814  * may fail because chip->data_buffer is not set (only set in tpm_open in Linux
 815  * TPM core)
 816  * @param: client, the i2c_client drescription (TPM I2C description).
 817  * @param: mesg, the power management message.
 818  * @return: 0 in case of success.
 819  */
 820 static int tpm_st33_i2c_pm_suspend(struct device *dev)
 821 {
 822         struct tpm_chip *chip = dev_get_drvdata(dev);
 823         struct st33zp24_platform_data *pin_infos = dev->platform_data;
 824         int ret = 0;
 825
 826         if (power_mgt)
 827                 gpio_set_value(pin_infos->io_lpcpd, 0);
 828         else{
 829                 if (chip->data_buffer == NULL)
 830                         chip->data_buffer = pin_infos->tpm_i2c_buffer[0];
 831                 ret = tpm_pm_suspend(dev);
 832         }
 833         return ret;
 834 }                               /* tpm_st33_i2c_suspend() */
 835
 836 /*
 837  * tpm_st33_i2c_pm_resume resume the TPM device
 838  * @param: client, the i2c_client drescription (TPM I2C description).
 839  * @return: 0 in case of success.
 840  */
 841 static int tpm_st33_i2c_pm_resume(struct device *dev)
 842 {
 843         struct tpm_chip *chip = dev_get_drvdata(dev);
 844         struct st33zp24_platform_data *pin_infos = dev->platform_data;
 845
 846         int ret = 0;
 847
 848         if (power_mgt) {
 849                 gpio_set_value(pin_infos->io_lpcpd, 1);
 850                 ret = wait_for_serirq_timeout(chip,
 851                                           (chip->vendor.status(chip) &
 852                                           TPM_STS_VALID) == TPM_STS_VALID,
 853                                           chip->vendor.timeout_b);
 854         } else{
 855         if (chip->data_buffer == NULL)
 856                 chip->data_buffer = pin_infos->tpm_i2c_buffer[0];
 857         ret = tpm_pm_resume(dev);
 858         if (!ret)
 859                 tpm_do_selftest(chip);
 860         }
 861         return ret;
 862 }                               /* tpm_st33_i2c_pm_resume() */
 863 #endif
 864
 865 static const struct i2c_device_id tpm_st33_i2c_id[] = {
 866         {TPM_ST33_I2C, 0},
 867         {}
 868 };
 869 MODULE_DEVICE_TABLE(i2c, tpm_st33_i2c_id);
 870 static SIMPLE_DEV_PM_OPS(tpm_st33_i2c_ops, tpm_st33_i2c_pm_suspend, tpm_st33_i2c_pm_resume);
 871 static struct i2c_driver tpm_st33_i2c_driver = {
 872         .driver = {
 873                    .owner = THIS_MODULE,
 874                    .name = TPM_ST33_I2C,
 875                    .pm = &tpm_st33_i2c_ops,
 876                    },
 877         .probe = tpm_st33_i2c_probe,
 878         .remove = tpm_st33_i2c_remove,
 879         .id_table = tpm_st33_i2c_id
 880 };
 881
 882 module_i2c_driver(tpm_st33_i2c_driver);
 883
 884 MODULE_AUTHOR("Christophe Ricard (tpmsupport@st.com)");
 885 MODULE_DESCRIPTION("STM TPM I2C ST33 Driver");
 886 MODULE_VERSION("1.2.0");
 887 MODULE_LICENSE("GPL");