2 * Copyright (C) 2004 IBM Corporation
5 * Leendert van Doorn <leendert@watson.ibm.com>
6 * Dave Safford <safford@watson.ibm.com>
7 * Reiner Sailer <sailer@watson.ibm.com>
8 * Kylene Hall <kjhall@us.ibm.com>
10 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
12 * Device driver for TCG/TCPA TPM (trusted platform module).
13 * Specifications at www.trustedcomputinggroup.org
15 * This program is free software; you can redistribute it and/or
16 * modify it under the terms of the GNU General Public License as
17 * published by the Free Software Foundation, version 2 of the
20 * Note, the TPM chip is not interrupt driven (only polling)
21 * and can have very long timeouts (minutes!). Hence the unusual
26 #include <linux/poll.h>
27 #include <linux/slab.h>
28 #include <linux/mutex.h>
29 #include <linux/spinlock.h>
34 TPM_MINOR = 224, /* officially assigned */
36 TPM_NUM_DEVICES = 256,
46 #define TPM_MAX_ORDINAL 243
47 #define TPM_MAX_PROTECTED_ORDINAL 12
48 #define TPM_PROTECTED_ORDINAL_MASK 0xFF
51 * Bug workaround - some TPM's don't flush the most
52 * recently changed pcr on suspend, so force the flush
53 * with an extend to the selected _unused_ non-volatile pcr.
55 static int tpm_suspend_pcr;
56 module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
57 MODULE_PARM_DESC(suspend_pcr,
58 "PCR to use for dummy writes to faciltate flush on suspend.");
60 static LIST_HEAD(tpm_chip_list);
61 static DEFINE_SPINLOCK(driver_lock);
62 static DECLARE_BITMAP(dev_mask, TPM_NUM_DEVICES);
65 * Array with one entry per ordinal defining the maximum amount
66 * of time the chip could take to return the result. The ordinal
67 * designation of short, medium or long is defined in a table in
68 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
69 * values of the SHORT, MEDIUM, and LONG durations are retrieved
70 * from the chip during initialization with a call to tpm_get_timeouts.
72 static const u8 tpm_protected_ordinal_duration[TPM_MAX_PROTECTED_ORDINAL] = {
73 TPM_UNDEFINED, /* 0 */
78 TPM_UNDEFINED, /* 5 */
87 static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
88 TPM_UNDEFINED, /* 0 */
93 TPM_UNDEFINED, /* 5 */
143 TPM_UNDEFINED, /* 55 */
163 TPM_UNDEFINED, /* 75 */
173 TPM_UNDEFINED, /* 85 */
183 TPM_UNDEFINED, /* 95 */
188 TPM_MEDIUM, /* 100 */
193 TPM_UNDEFINED, /* 105 */
223 TPM_UNDEFINED, /* 135 */
233 TPM_UNDEFINED, /* 145 */
243 TPM_UNDEFINED, /* 155 */
253 TPM_UNDEFINED, /* 165 */
263 TPM_UNDEFINED, /* 175 */
268 TPM_MEDIUM, /* 180 */
273 TPM_MEDIUM, /* 185 */
278 TPM_UNDEFINED, /* 190 */
283 TPM_UNDEFINED, /* 195 */
298 TPM_MEDIUM, /* 210 */
303 TPM_UNDEFINED, /* 215 */
313 TPM_UNDEFINED, /* 225 */
323 TPM_UNDEFINED, /* 235 */
333 static void user_reader_timeout(unsigned long ptr)
335 struct tpm_chip *chip = (struct tpm_chip *) ptr;
337 schedule_work(&chip->work);
340 static void timeout_work(struct work_struct *work)
342 struct tpm_chip *chip = container_of(work, struct tpm_chip, work);
344 mutex_lock(&chip->buffer_mutex);
345 atomic_set(&chip->data_pending, 0);
346 memset(chip->data_buffer, 0, TPM_BUFSIZE);
347 mutex_unlock(&chip->buffer_mutex);
351 * Returns max number of jiffies to wait
353 unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
356 int duration_idx = TPM_UNDEFINED;
359 if (ordinal < TPM_MAX_ORDINAL)
360 duration_idx = tpm_ordinal_duration[ordinal];
361 else if ((ordinal & TPM_PROTECTED_ORDINAL_MASK) <
362 TPM_MAX_PROTECTED_ORDINAL)
364 tpm_protected_ordinal_duration[ordinal &
365 TPM_PROTECTED_ORDINAL_MASK];
367 if (duration_idx != TPM_UNDEFINED)
368 duration = chip->vendor.duration[duration_idx];
374 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
377 * Internal kernel interface to transmit TPM commands
379 static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
386 count = be32_to_cpu(*((__be32 *) (buf + 2)));
387 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
390 if (count > bufsiz) {
392 "invalid count value %x %zx \n", count, bufsiz);
396 mutex_lock(&chip->tpm_mutex);
398 if ((rc = chip->vendor.send(chip, (u8 *) buf, count)) < 0) {
400 "tpm_transmit: tpm_send: error %zd\n", rc);
404 if (chip->vendor.irq)
407 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
409 u8 status = chip->vendor.status(chip);
410 if ((status & chip->vendor.req_complete_mask) ==
411 chip->vendor.req_complete_val)
414 if ((status == chip->vendor.req_canceled)) {
415 dev_err(chip->dev, "Operation Canceled\n");
420 msleep(TPM_TIMEOUT); /* CHECK */
422 } while (time_before(jiffies, stop));
424 chip->vendor.cancel(chip);
425 dev_err(chip->dev, "Operation Timed out\n");
430 rc = chip->vendor.recv(chip, (u8 *) buf, bufsiz);
433 "tpm_transmit: tpm_recv: error %zd\n", rc);
435 mutex_unlock(&chip->tpm_mutex);
439 #define TPM_DIGEST_SIZE 20
440 #define TPM_ERROR_SIZE 10
441 #define TPM_RET_CODE_IDX 6
443 enum tpm_capabilities {
444 TPM_CAP_FLAG = cpu_to_be32(4),
445 TPM_CAP_PROP = cpu_to_be32(5),
446 CAP_VERSION_1_1 = cpu_to_be32(0x06),
447 CAP_VERSION_1_2 = cpu_to_be32(0x1A)
450 enum tpm_sub_capabilities {
451 TPM_CAP_PROP_PCR = cpu_to_be32(0x101),
452 TPM_CAP_PROP_MANUFACTURER = cpu_to_be32(0x103),
453 TPM_CAP_FLAG_PERM = cpu_to_be32(0x108),
454 TPM_CAP_FLAG_VOL = cpu_to_be32(0x109),
455 TPM_CAP_PROP_OWNER = cpu_to_be32(0x111),
456 TPM_CAP_PROP_TIS_TIMEOUT = cpu_to_be32(0x115),
457 TPM_CAP_PROP_TIS_DURATION = cpu_to_be32(0x120),
461 static ssize_t transmit_cmd(struct tpm_chip *chip, struct tpm_cmd_t *cmd,
462 int len, const char *desc)
466 len = tpm_transmit(chip,(u8 *) cmd, len);
469 if (len == TPM_ERROR_SIZE) {
470 err = be32_to_cpu(cmd->header.out.return_code);
471 dev_dbg(chip->dev, "A TPM error (%d) occurred %s\n", err, desc);
477 #define TPM_INTERNAL_RESULT_SIZE 200
478 #define TPM_TAG_RQU_COMMAND cpu_to_be16(193)
479 #define TPM_ORD_GET_CAP cpu_to_be32(101)
481 static const struct tpm_input_header tpm_getcap_header = {
482 .tag = TPM_TAG_RQU_COMMAND,
483 .length = cpu_to_be32(22),
484 .ordinal = TPM_ORD_GET_CAP
487 ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
490 struct tpm_cmd_t tpm_cmd;
492 struct tpm_chip *chip = dev_get_drvdata(dev);
494 tpm_cmd.header.in = tpm_getcap_header;
495 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
496 tpm_cmd.params.getcap_in.cap = subcap_id;
497 /*subcap field not necessary */
498 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
499 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
501 if (subcap_id == TPM_CAP_FLAG_PERM ||
502 subcap_id == TPM_CAP_FLAG_VOL)
503 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
505 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
506 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
507 tpm_cmd.params.getcap_in.subcap = subcap_id;
509 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
511 *cap = tpm_cmd.params.getcap_out.cap;
515 void tpm_gen_interrupt(struct tpm_chip *chip)
517 struct tpm_cmd_t tpm_cmd;
520 tpm_cmd.header.in = tpm_getcap_header;
521 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
522 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
523 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
525 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
526 "attempting to determine the timeouts");
528 EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
530 void tpm_get_timeouts(struct tpm_chip *chip)
532 struct tpm_cmd_t tpm_cmd;
533 struct timeout_t *timeout_cap;
534 struct duration_t *duration_cap;
538 tpm_cmd.header.in = tpm_getcap_header;
539 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
540 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
541 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
543 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
544 "attempting to determine the timeouts");
548 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
549 be32_to_cpu(tpm_cmd.header.out.length)
550 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 4 * sizeof(u32))
553 timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
554 /* Don't overwrite default if value is 0 */
555 timeout = be32_to_cpu(timeout_cap->a);
557 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
558 timeout = be32_to_cpu(timeout_cap->b);
560 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
561 timeout = be32_to_cpu(timeout_cap->c);
563 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
564 timeout = be32_to_cpu(timeout_cap->d);
566 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
569 tpm_cmd.header.in = tpm_getcap_header;
570 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
571 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
572 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
574 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
575 "attempting to determine the durations");
579 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
580 be32_to_cpu(tpm_cmd.header.out.length)
581 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
584 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
585 chip->vendor.duration[TPM_SHORT] =
586 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
587 chip->vendor.duration[TPM_MEDIUM] =
588 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
589 chip->vendor.duration[TPM_LONG] =
590 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
592 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
593 * value wrong and apparently reports msecs rather than usecs. So we
594 * fix up the resulting too-small TPM_SHORT value to make things work.
595 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
597 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
598 chip->vendor.duration[TPM_SHORT] = HZ;
599 chip->vendor.duration[TPM_MEDIUM] *= 1000;
600 chip->vendor.duration[TPM_LONG] *= 1000;
601 chip->vendor.duration_adjusted = true;
602 dev_info(chip->dev, "Adjusting TPM timeout parameters.");
605 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
607 void tpm_continue_selftest(struct tpm_chip *chip)
610 0, 193, /* TPM_TAG_RQU_COMMAND */
611 0, 0, 0, 10, /* length */
612 0, 0, 0, 83, /* TPM_ORD_GetCapability */
615 tpm_transmit(chip, data, sizeof(data));
617 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
619 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
625 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
626 "attempting to determine the permanent enabled state");
630 rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
633 EXPORT_SYMBOL_GPL(tpm_show_enabled);
635 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
641 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
642 "attempting to determine the permanent active state");
646 rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
649 EXPORT_SYMBOL_GPL(tpm_show_active);
651 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
657 rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
658 "attempting to determine the owner state");
662 rc = sprintf(buf, "%d\n", cap.owned);
665 EXPORT_SYMBOL_GPL(tpm_show_owned);
667 ssize_t tpm_show_temp_deactivated(struct device * dev,
668 struct device_attribute * attr, char *buf)
673 rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
674 "attempting to determine the temporary state");
678 rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
681 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
684 * tpm_chip_find_get - return tpm_chip for given chip number
686 static struct tpm_chip *tpm_chip_find_get(int chip_num)
688 struct tpm_chip *pos, *chip = NULL;
691 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
692 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
695 if (try_module_get(pos->dev->driver->owner)) {
704 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
705 #define READ_PCR_RESULT_SIZE 30
706 static struct tpm_input_header pcrread_header = {
707 .tag = TPM_TAG_RQU_COMMAND,
708 .length = cpu_to_be32(14),
709 .ordinal = TPM_ORDINAL_PCRREAD
712 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
715 struct tpm_cmd_t cmd;
717 cmd.header.in = pcrread_header;
718 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
719 rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
720 "attempting to read a pcr value");
723 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
729 * tpm_pcr_read - read a pcr value
730 * @chip_num: tpm idx # or ANY
731 * @pcr_idx: pcr idx to retrieve
732 * @res_buf: TPM_PCR value
733 * size of res_buf is 20 bytes (or NULL if you don't care)
735 * The TPM driver should be built-in, but for whatever reason it
736 * isn't, protect against the chip disappearing, by incrementing
737 * the module usage count.
739 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
741 struct tpm_chip *chip;
744 chip = tpm_chip_find_get(chip_num);
747 rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
751 EXPORT_SYMBOL_GPL(tpm_pcr_read);
754 * tpm_pcr_extend - extend pcr value with hash
755 * @chip_num: tpm idx # or AN&
756 * @pcr_idx: pcr idx to extend
757 * @hash: hash value used to extend pcr value
759 * The TPM driver should be built-in, but for whatever reason it
760 * isn't, protect against the chip disappearing, by incrementing
761 * the module usage count.
763 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
764 #define EXTEND_PCR_RESULT_SIZE 34
765 static struct tpm_input_header pcrextend_header = {
766 .tag = TPM_TAG_RQU_COMMAND,
767 .length = cpu_to_be32(34),
768 .ordinal = TPM_ORD_PCR_EXTEND
771 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
773 struct tpm_cmd_t cmd;
775 struct tpm_chip *chip;
777 chip = tpm_chip_find_get(chip_num);
781 cmd.header.in = pcrextend_header;
782 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
783 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
784 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
785 "attempting extend a PCR value");
790 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
792 int tpm_send(u32 chip_num, void *cmd, size_t buflen)
794 struct tpm_chip *chip;
797 chip = tpm_chip_find_get(chip_num);
801 rc = transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
806 EXPORT_SYMBOL_GPL(tpm_send);
808 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
812 u8 digest[TPM_DIGEST_SIZE];
816 struct tpm_chip *chip = dev_get_drvdata(dev);
818 rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
819 "attempting to determine the number of PCRS");
823 num_pcrs = be32_to_cpu(cap.num_pcrs);
824 for (i = 0; i < num_pcrs; i++) {
825 rc = __tpm_pcr_read(chip, i, digest);
828 str += sprintf(str, "PCR-%02d: ", i);
829 for (j = 0; j < TPM_DIGEST_SIZE; j++)
830 str += sprintf(str, "%02X ", digest[j]);
831 str += sprintf(str, "\n");
835 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
837 #define READ_PUBEK_RESULT_SIZE 314
838 #define TPM_ORD_READPUBEK cpu_to_be32(124)
839 struct tpm_input_header tpm_readpubek_header = {
840 .tag = TPM_TAG_RQU_COMMAND,
841 .length = cpu_to_be32(30),
842 .ordinal = TPM_ORD_READPUBEK
845 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
849 struct tpm_cmd_t tpm_cmd;
854 struct tpm_chip *chip = dev_get_drvdata(dev);
856 tpm_cmd.header.in = tpm_readpubek_header;
857 err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
858 "attempting to read the PUBEK");
863 ignore header 10 bytes
864 algorithm 32 bits (1 == RSA )
867 parameters (RSA 12->bytes: keybit, #primes, expbit)
870 ignore checksum 20 bytes
872 data = tpm_cmd.params.readpubek_out_buffer;
875 "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
876 "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
877 " %02X %02X %02X %02X %02X %02X %02X %02X\n"
878 "Modulus length: %d\nModulus: \n",
879 data[10], data[11], data[12], data[13], data[14],
880 data[15], data[16], data[17], data[22], data[23],
881 data[24], data[25], data[26], data[27], data[28],
882 data[29], data[30], data[31], data[32], data[33],
883 be32_to_cpu(*((__be32 *) (data + 34))));
885 for (i = 0; i < 256; i++) {
886 str += sprintf(str, "%02X ", data[i + 38]);
887 if ((i + 1) % 16 == 0)
888 str += sprintf(str, "\n");
894 EXPORT_SYMBOL_GPL(tpm_show_pubek);
897 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
904 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
905 "attempting to determine the manufacturer");
908 str += sprintf(str, "Manufacturer: 0x%x\n",
909 be32_to_cpu(cap.manufacturer_id));
911 rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
912 "attempting to determine the 1.1 version");
916 "TCG version: %d.%d\nFirmware version: %d.%d\n",
917 cap.tpm_version.Major, cap.tpm_version.Minor,
918 cap.tpm_version.revMajor, cap.tpm_version.revMinor);
921 EXPORT_SYMBOL_GPL(tpm_show_caps);
923 ssize_t tpm_show_caps_1_2(struct device * dev,
924 struct device_attribute * attr, char *buf)
930 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
931 "attempting to determine the manufacturer");
934 str += sprintf(str, "Manufacturer: 0x%x\n",
935 be32_to_cpu(cap.manufacturer_id));
936 rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
937 "attempting to determine the 1.2 version");
941 "TCG version: %d.%d\nFirmware version: %d.%d\n",
942 cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
943 cap.tpm_version_1_2.revMajor,
944 cap.tpm_version_1_2.revMinor);
947 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
949 ssize_t tpm_show_durations(struct device *dev, struct device_attribute *attr,
952 struct tpm_chip *chip = dev_get_drvdata(dev);
954 return sprintf(buf, "%d %d %d [%s]\n",
955 jiffies_to_usecs(chip->vendor.duration[TPM_SHORT]),
956 jiffies_to_usecs(chip->vendor.duration[TPM_MEDIUM]),
957 jiffies_to_usecs(chip->vendor.duration[TPM_LONG]),
958 chip->vendor.duration_adjusted
959 ? "adjusted" : "original");
961 EXPORT_SYMBOL_GPL(tpm_show_durations);
963 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
964 const char *buf, size_t count)
966 struct tpm_chip *chip = dev_get_drvdata(dev);
970 chip->vendor.cancel(chip);
973 EXPORT_SYMBOL_GPL(tpm_store_cancel);
976 * Device file system interface to the TPM
978 * It's assured that the chip will be opened just once,
979 * by the check of is_open variable, which is protected
982 int tpm_open(struct inode *inode, struct file *file)
984 int minor = iminor(inode);
985 struct tpm_chip *chip = NULL, *pos;
988 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
989 if (pos->vendor.miscdev.minor == minor) {
991 get_device(chip->dev);
1000 if (test_and_set_bit(0, &chip->is_open)) {
1001 dev_dbg(chip->dev, "Another process owns this TPM\n");
1002 put_device(chip->dev);
1006 chip->data_buffer = kzalloc(TPM_BUFSIZE, GFP_KERNEL);
1007 if (chip->data_buffer == NULL) {
1008 clear_bit(0, &chip->is_open);
1009 put_device(chip->dev);
1013 atomic_set(&chip->data_pending, 0);
1015 file->private_data = chip;
1018 EXPORT_SYMBOL_GPL(tpm_open);
1021 * Called on file close
1023 int tpm_release(struct inode *inode, struct file *file)
1025 struct tpm_chip *chip = file->private_data;
1027 del_singleshot_timer_sync(&chip->user_read_timer);
1028 flush_work_sync(&chip->work);
1029 file->private_data = NULL;
1030 atomic_set(&chip->data_pending, 0);
1031 kfree(chip->data_buffer);
1032 clear_bit(0, &chip->is_open);
1033 put_device(chip->dev);
1036 EXPORT_SYMBOL_GPL(tpm_release);
1038 ssize_t tpm_write(struct file *file, const char __user *buf,
1039 size_t size, loff_t *off)
1041 struct tpm_chip *chip = file->private_data;
1042 size_t in_size = size, out_size;
1044 /* cannot perform a write until the read has cleared
1045 either via tpm_read or a user_read_timer timeout */
1046 while (atomic_read(&chip->data_pending) != 0)
1047 msleep(TPM_TIMEOUT);
1049 mutex_lock(&chip->buffer_mutex);
1051 if (in_size > TPM_BUFSIZE)
1052 in_size = TPM_BUFSIZE;
1055 (chip->data_buffer, (void __user *) buf, in_size)) {
1056 mutex_unlock(&chip->buffer_mutex);
1060 /* atomic tpm command send and result receive */
1061 out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1063 atomic_set(&chip->data_pending, out_size);
1064 mutex_unlock(&chip->buffer_mutex);
1066 /* Set a timeout by which the reader must come claim the result */
1067 mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1071 EXPORT_SYMBOL_GPL(tpm_write);
1073 ssize_t tpm_read(struct file *file, char __user *buf,
1074 size_t size, loff_t *off)
1076 struct tpm_chip *chip = file->private_data;
1079 del_singleshot_timer_sync(&chip->user_read_timer);
1080 flush_work_sync(&chip->work);
1081 ret_size = atomic_read(&chip->data_pending);
1082 atomic_set(&chip->data_pending, 0);
1083 if (ret_size > 0) { /* relay data */
1084 if (size < ret_size)
1087 mutex_lock(&chip->buffer_mutex);
1088 if (copy_to_user(buf, chip->data_buffer, ret_size))
1090 mutex_unlock(&chip->buffer_mutex);
1095 EXPORT_SYMBOL_GPL(tpm_read);
1097 void tpm_remove_hardware(struct device *dev)
1099 struct tpm_chip *chip = dev_get_drvdata(dev);
1102 dev_err(dev, "No device data found\n");
1106 spin_lock(&driver_lock);
1107 list_del_rcu(&chip->list);
1108 spin_unlock(&driver_lock);
1111 misc_deregister(&chip->vendor.miscdev);
1112 sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1113 tpm_bios_log_teardown(chip->bios_dir);
1115 /* write it this way to be explicit (chip->dev == dev) */
1116 put_device(chip->dev);
1118 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1120 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1121 #define SAVESTATE_RESULT_SIZE 10
1123 static struct tpm_input_header savestate_header = {
1124 .tag = TPM_TAG_RQU_COMMAND,
1125 .length = cpu_to_be32(10),
1126 .ordinal = TPM_ORD_SAVESTATE
1130 * We are about to suspend. Save the TPM state
1131 * so that it can be restored.
1133 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1135 struct tpm_chip *chip = dev_get_drvdata(dev);
1136 struct tpm_cmd_t cmd;
1139 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1144 /* for buggy tpm, flush pcrs with extend to selected dummy */
1145 if (tpm_suspend_pcr) {
1146 cmd.header.in = pcrextend_header;
1147 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1148 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1150 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1151 "extending dummy pcr before suspend");
1154 /* now do the actual savestate */
1155 cmd.header.in = savestate_header;
1156 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1157 "sending savestate before suspend");
1160 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1163 * Resume from a power safe. The BIOS already restored
1166 int tpm_pm_resume(struct device *dev)
1168 struct tpm_chip *chip = dev_get_drvdata(dev);
1175 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1177 /* In case vendor provided release function, call it too.*/
1179 void tpm_dev_vendor_release(struct tpm_chip *chip)
1181 if (chip->vendor.release)
1182 chip->vendor.release(chip->dev);
1184 clear_bit(chip->dev_num, dev_mask);
1185 kfree(chip->vendor.miscdev.name);
1187 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1191 * Once all references to platform device are down to 0,
1192 * release all allocated structures.
1194 void tpm_dev_release(struct device *dev)
1196 struct tpm_chip *chip = dev_get_drvdata(dev);
1198 tpm_dev_vendor_release(chip);
1203 EXPORT_SYMBOL_GPL(tpm_dev_release);
1206 * Called from tpm_<specific>.c probe function only for devices
1207 * the driver has determined it should claim. Prior to calling
1208 * this function the specific probe function has called pci_enable_device
1209 * upon errant exit from this function specific probe function should call
1210 * pci_disable_device
1212 struct tpm_chip *tpm_register_hardware(struct device *dev,
1213 const struct tpm_vendor_specific *entry)
1215 #define DEVNAME_SIZE 7
1218 struct tpm_chip *chip;
1220 /* Driver specific per-device data */
1221 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1222 devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1224 if (chip == NULL || devname == NULL)
1227 mutex_init(&chip->buffer_mutex);
1228 mutex_init(&chip->tpm_mutex);
1229 INIT_LIST_HEAD(&chip->list);
1231 INIT_WORK(&chip->work, timeout_work);
1233 setup_timer(&chip->user_read_timer, user_reader_timeout,
1234 (unsigned long)chip);
1236 memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1238 chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1240 if (chip->dev_num >= TPM_NUM_DEVICES) {
1241 dev_err(dev, "No available tpm device numbers\n");
1243 } else if (chip->dev_num == 0)
1244 chip->vendor.miscdev.minor = TPM_MINOR;
1246 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1248 set_bit(chip->dev_num, dev_mask);
1250 scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1251 chip->vendor.miscdev.name = devname;
1253 chip->vendor.miscdev.parent = dev;
1254 chip->dev = get_device(dev);
1255 chip->release = dev->release;
1256 dev->release = tpm_dev_release;
1257 dev_set_drvdata(dev, chip);
1259 if (misc_register(&chip->vendor.miscdev)) {
1261 "unable to misc_register %s, minor %d\n",
1262 chip->vendor.miscdev.name,
1263 chip->vendor.miscdev.minor);
1264 put_device(chip->dev);
1268 if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1269 misc_deregister(&chip->vendor.miscdev);
1270 put_device(chip->dev);
1275 chip->bios_dir = tpm_bios_log_setup(devname);
1277 /* Make chip available */
1278 spin_lock(&driver_lock);
1279 list_add_rcu(&chip->list, &tpm_chip_list);
1280 spin_unlock(&driver_lock);
1289 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1291 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1292 MODULE_DESCRIPTION("TPM Driver");
1293 MODULE_VERSION("2.0");
1294 MODULE_LICENSE("GPL");