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.length)
552 timeout_cap = &tpm_cmd.params.getcap_out.cap.timeout;
553 /* Don't overwrite default if value is 0 */
554 timeout = be32_to_cpu(timeout_cap->a);
556 chip->vendor.timeout_a = usecs_to_jiffies(timeout);
557 timeout = be32_to_cpu(timeout_cap->b);
559 chip->vendor.timeout_b = usecs_to_jiffies(timeout);
560 timeout = be32_to_cpu(timeout_cap->c);
562 chip->vendor.timeout_c = usecs_to_jiffies(timeout);
563 timeout = be32_to_cpu(timeout_cap->d);
565 chip->vendor.timeout_d = usecs_to_jiffies(timeout);
568 tpm_cmd.header.in = tpm_getcap_header;
569 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
570 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
571 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
573 rc = transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
574 "attempting to determine the durations");
578 if (be32_to_cpu(tpm_cmd.header.out.return_code)
581 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
582 chip->vendor.duration[TPM_SHORT] =
583 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
584 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
585 * value wrong and apparently reports msecs rather than usecs. So we
586 * fix up the resulting too-small TPM_SHORT value to make things work.
588 if (chip->vendor.duration[TPM_SHORT] < (HZ/100))
589 chip->vendor.duration[TPM_SHORT] = HZ;
591 chip->vendor.duration[TPM_MEDIUM] =
592 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
593 chip->vendor.duration[TPM_LONG] =
594 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
596 EXPORT_SYMBOL_GPL(tpm_get_timeouts);
598 void tpm_continue_selftest(struct tpm_chip *chip)
601 0, 193, /* TPM_TAG_RQU_COMMAND */
602 0, 0, 0, 10, /* length */
603 0, 0, 0, 83, /* TPM_ORD_GetCapability */
606 tpm_transmit(chip, data, sizeof(data));
608 EXPORT_SYMBOL_GPL(tpm_continue_selftest);
610 ssize_t tpm_show_enabled(struct device * dev, struct device_attribute * attr,
616 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
617 "attempting to determine the permanent enabled state");
621 rc = sprintf(buf, "%d\n", !cap.perm_flags.disable);
624 EXPORT_SYMBOL_GPL(tpm_show_enabled);
626 ssize_t tpm_show_active(struct device * dev, struct device_attribute * attr,
632 rc = tpm_getcap(dev, TPM_CAP_FLAG_PERM, &cap,
633 "attempting to determine the permanent active state");
637 rc = sprintf(buf, "%d\n", !cap.perm_flags.deactivated);
640 EXPORT_SYMBOL_GPL(tpm_show_active);
642 ssize_t tpm_show_owned(struct device * dev, struct device_attribute * attr,
648 rc = tpm_getcap(dev, TPM_CAP_PROP_OWNER, &cap,
649 "attempting to determine the owner state");
653 rc = sprintf(buf, "%d\n", cap.owned);
656 EXPORT_SYMBOL_GPL(tpm_show_owned);
658 ssize_t tpm_show_temp_deactivated(struct device * dev,
659 struct device_attribute * attr, char *buf)
664 rc = tpm_getcap(dev, TPM_CAP_FLAG_VOL, &cap,
665 "attempting to determine the temporary state");
669 rc = sprintf(buf, "%d\n", cap.stclear_flags.deactivated);
672 EXPORT_SYMBOL_GPL(tpm_show_temp_deactivated);
675 * tpm_chip_find_get - return tpm_chip for given chip number
677 static struct tpm_chip *tpm_chip_find_get(int chip_num)
679 struct tpm_chip *pos, *chip = NULL;
682 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
683 if (chip_num != TPM_ANY_NUM && chip_num != pos->dev_num)
686 if (try_module_get(pos->dev->driver->owner)) {
695 #define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
696 #define READ_PCR_RESULT_SIZE 30
697 static struct tpm_input_header pcrread_header = {
698 .tag = TPM_TAG_RQU_COMMAND,
699 .length = cpu_to_be32(14),
700 .ordinal = TPM_ORDINAL_PCRREAD
703 int __tpm_pcr_read(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
706 struct tpm_cmd_t cmd;
708 cmd.header.in = pcrread_header;
709 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
710 rc = transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
711 "attempting to read a pcr value");
714 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
720 * tpm_pcr_read - read a pcr value
721 * @chip_num: tpm idx # or ANY
722 * @pcr_idx: pcr idx to retrieve
723 * @res_buf: TPM_PCR value
724 * size of res_buf is 20 bytes (or NULL if you don't care)
726 * The TPM driver should be built-in, but for whatever reason it
727 * isn't, protect against the chip disappearing, by incrementing
728 * the module usage count.
730 int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
732 struct tpm_chip *chip;
735 chip = tpm_chip_find_get(chip_num);
738 rc = __tpm_pcr_read(chip, pcr_idx, res_buf);
739 module_put(chip->dev->driver->owner);
742 EXPORT_SYMBOL_GPL(tpm_pcr_read);
745 * tpm_pcr_extend - extend pcr value with hash
746 * @chip_num: tpm idx # or AN&
747 * @pcr_idx: pcr idx to extend
748 * @hash: hash value used to extend pcr value
750 * The TPM driver should be built-in, but for whatever reason it
751 * isn't, protect against the chip disappearing, by incrementing
752 * the module usage count.
754 #define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
755 #define EXTEND_PCR_RESULT_SIZE 34
756 static struct tpm_input_header pcrextend_header = {
757 .tag = TPM_TAG_RQU_COMMAND,
758 .length = cpu_to_be32(34),
759 .ordinal = TPM_ORD_PCR_EXTEND
762 int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
764 struct tpm_cmd_t cmd;
766 struct tpm_chip *chip;
768 chip = tpm_chip_find_get(chip_num);
772 cmd.header.in = pcrextend_header;
773 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
774 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
775 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
776 "attempting extend a PCR value");
778 module_put(chip->dev->driver->owner);
781 EXPORT_SYMBOL_GPL(tpm_pcr_extend);
783 ssize_t tpm_show_pcrs(struct device *dev, struct device_attribute *attr,
787 u8 digest[TPM_DIGEST_SIZE];
791 struct tpm_chip *chip = dev_get_drvdata(dev);
793 rc = tpm_getcap(dev, TPM_CAP_PROP_PCR, &cap,
794 "attempting to determine the number of PCRS");
798 num_pcrs = be32_to_cpu(cap.num_pcrs);
799 for (i = 0; i < num_pcrs; i++) {
800 rc = __tpm_pcr_read(chip, i, digest);
803 str += sprintf(str, "PCR-%02d: ", i);
804 for (j = 0; j < TPM_DIGEST_SIZE; j++)
805 str += sprintf(str, "%02X ", digest[j]);
806 str += sprintf(str, "\n");
810 EXPORT_SYMBOL_GPL(tpm_show_pcrs);
812 #define READ_PUBEK_RESULT_SIZE 314
813 #define TPM_ORD_READPUBEK cpu_to_be32(124)
814 struct tpm_input_header tpm_readpubek_header = {
815 .tag = TPM_TAG_RQU_COMMAND,
816 .length = cpu_to_be32(30),
817 .ordinal = TPM_ORD_READPUBEK
820 ssize_t tpm_show_pubek(struct device *dev, struct device_attribute *attr,
824 struct tpm_cmd_t tpm_cmd;
829 struct tpm_chip *chip = dev_get_drvdata(dev);
831 tpm_cmd.header.in = tpm_readpubek_header;
832 err = transmit_cmd(chip, &tpm_cmd, READ_PUBEK_RESULT_SIZE,
833 "attempting to read the PUBEK");
838 ignore header 10 bytes
839 algorithm 32 bits (1 == RSA )
842 parameters (RSA 12->bytes: keybit, #primes, expbit)
845 ignore checksum 20 bytes
847 data = tpm_cmd.params.readpubek_out_buffer;
850 "Algorithm: %02X %02X %02X %02X\nEncscheme: %02X %02X\n"
851 "Sigscheme: %02X %02X\nParameters: %02X %02X %02X %02X"
852 " %02X %02X %02X %02X %02X %02X %02X %02X\n"
853 "Modulus length: %d\nModulus: \n",
854 data[10], data[11], data[12], data[13], data[14],
855 data[15], data[16], data[17], data[22], data[23],
856 data[24], data[25], data[26], data[27], data[28],
857 data[29], data[30], data[31], data[32], data[33],
858 be32_to_cpu(*((__be32 *) (data + 34))));
860 for (i = 0; i < 256; i++) {
861 str += sprintf(str, "%02X ", data[i + 38]);
862 if ((i + 1) % 16 == 0)
863 str += sprintf(str, "\n");
869 EXPORT_SYMBOL_GPL(tpm_show_pubek);
872 ssize_t tpm_show_caps(struct device *dev, struct device_attribute *attr,
879 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
880 "attempting to determine the manufacturer");
883 str += sprintf(str, "Manufacturer: 0x%x\n",
884 be32_to_cpu(cap.manufacturer_id));
886 rc = tpm_getcap(dev, CAP_VERSION_1_1, &cap,
887 "attempting to determine the 1.1 version");
891 "TCG version: %d.%d\nFirmware version: %d.%d\n",
892 cap.tpm_version.Major, cap.tpm_version.Minor,
893 cap.tpm_version.revMajor, cap.tpm_version.revMinor);
896 EXPORT_SYMBOL_GPL(tpm_show_caps);
898 ssize_t tpm_show_caps_1_2(struct device * dev,
899 struct device_attribute * attr, char *buf)
905 rc = tpm_getcap(dev, TPM_CAP_PROP_MANUFACTURER, &cap,
906 "attempting to determine the manufacturer");
909 str += sprintf(str, "Manufacturer: 0x%x\n",
910 be32_to_cpu(cap.manufacturer_id));
911 rc = tpm_getcap(dev, CAP_VERSION_1_2, &cap,
912 "attempting to determine the 1.2 version");
916 "TCG version: %d.%d\nFirmware version: %d.%d\n",
917 cap.tpm_version_1_2.Major, cap.tpm_version_1_2.Minor,
918 cap.tpm_version_1_2.revMajor,
919 cap.tpm_version_1_2.revMinor);
922 EXPORT_SYMBOL_GPL(tpm_show_caps_1_2);
924 ssize_t tpm_store_cancel(struct device *dev, struct device_attribute *attr,
925 const char *buf, size_t count)
927 struct tpm_chip *chip = dev_get_drvdata(dev);
931 chip->vendor.cancel(chip);
934 EXPORT_SYMBOL_GPL(tpm_store_cancel);
937 * Device file system interface to the TPM
939 * It's assured that the chip will be opened just once,
940 * by the check of is_open variable, which is protected
943 int tpm_open(struct inode *inode, struct file *file)
945 int minor = iminor(inode);
946 struct tpm_chip *chip = NULL, *pos;
949 list_for_each_entry_rcu(pos, &tpm_chip_list, list) {
950 if (pos->vendor.miscdev.minor == minor) {
952 get_device(chip->dev);
961 if (test_and_set_bit(0, &chip->is_open)) {
962 dev_dbg(chip->dev, "Another process owns this TPM\n");
963 put_device(chip->dev);
967 chip->data_buffer = kmalloc(TPM_BUFSIZE * sizeof(u8), GFP_KERNEL);
968 if (chip->data_buffer == NULL) {
969 clear_bit(0, &chip->is_open);
970 put_device(chip->dev);
974 atomic_set(&chip->data_pending, 0);
976 file->private_data = chip;
979 EXPORT_SYMBOL_GPL(tpm_open);
982 * Called on file close
984 int tpm_release(struct inode *inode, struct file *file)
986 struct tpm_chip *chip = file->private_data;
988 del_singleshot_timer_sync(&chip->user_read_timer);
989 flush_work_sync(&chip->work);
990 file->private_data = NULL;
991 atomic_set(&chip->data_pending, 0);
992 kfree(chip->data_buffer);
993 clear_bit(0, &chip->is_open);
994 put_device(chip->dev);
997 EXPORT_SYMBOL_GPL(tpm_release);
999 ssize_t tpm_write(struct file *file, const char __user *buf,
1000 size_t size, loff_t *off)
1002 struct tpm_chip *chip = file->private_data;
1003 size_t in_size = size, out_size;
1005 /* cannot perform a write until the read has cleared
1006 either via tpm_read or a user_read_timer timeout */
1007 while (atomic_read(&chip->data_pending) != 0)
1008 msleep(TPM_TIMEOUT);
1010 mutex_lock(&chip->buffer_mutex);
1012 if (in_size > TPM_BUFSIZE)
1013 in_size = TPM_BUFSIZE;
1016 (chip->data_buffer, (void __user *) buf, in_size)) {
1017 mutex_unlock(&chip->buffer_mutex);
1021 /* atomic tpm command send and result receive */
1022 out_size = tpm_transmit(chip, chip->data_buffer, TPM_BUFSIZE);
1024 atomic_set(&chip->data_pending, out_size);
1025 mutex_unlock(&chip->buffer_mutex);
1027 /* Set a timeout by which the reader must come claim the result */
1028 mod_timer(&chip->user_read_timer, jiffies + (60 * HZ));
1032 EXPORT_SYMBOL_GPL(tpm_write);
1034 ssize_t tpm_read(struct file *file, char __user *buf,
1035 size_t size, loff_t *off)
1037 struct tpm_chip *chip = file->private_data;
1040 del_singleshot_timer_sync(&chip->user_read_timer);
1041 flush_work_sync(&chip->work);
1042 ret_size = atomic_read(&chip->data_pending);
1043 atomic_set(&chip->data_pending, 0);
1044 if (ret_size > 0) { /* relay data */
1045 if (size < ret_size)
1048 mutex_lock(&chip->buffer_mutex);
1049 if (copy_to_user(buf, chip->data_buffer, ret_size))
1051 mutex_unlock(&chip->buffer_mutex);
1056 EXPORT_SYMBOL_GPL(tpm_read);
1058 void tpm_remove_hardware(struct device *dev)
1060 struct tpm_chip *chip = dev_get_drvdata(dev);
1063 dev_err(dev, "No device data found\n");
1067 spin_lock(&driver_lock);
1068 list_del_rcu(&chip->list);
1069 spin_unlock(&driver_lock);
1072 misc_deregister(&chip->vendor.miscdev);
1073 sysfs_remove_group(&dev->kobj, chip->vendor.attr_group);
1074 tpm_bios_log_teardown(chip->bios_dir);
1076 /* write it this way to be explicit (chip->dev == dev) */
1077 put_device(chip->dev);
1079 EXPORT_SYMBOL_GPL(tpm_remove_hardware);
1081 #define TPM_ORD_SAVESTATE cpu_to_be32(152)
1082 #define SAVESTATE_RESULT_SIZE 10
1084 static struct tpm_input_header savestate_header = {
1085 .tag = TPM_TAG_RQU_COMMAND,
1086 .length = cpu_to_be32(10),
1087 .ordinal = TPM_ORD_SAVESTATE
1091 * We are about to suspend. Save the TPM state
1092 * so that it can be restored.
1094 int tpm_pm_suspend(struct device *dev, pm_message_t pm_state)
1096 struct tpm_chip *chip = dev_get_drvdata(dev);
1097 struct tpm_cmd_t cmd;
1100 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
1105 /* for buggy tpm, flush pcrs with extend to selected dummy */
1106 if (tpm_suspend_pcr) {
1107 cmd.header.in = pcrextend_header;
1108 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
1109 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
1111 rc = transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
1112 "extending dummy pcr before suspend");
1115 /* now do the actual savestate */
1116 cmd.header.in = savestate_header;
1117 rc = transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE,
1118 "sending savestate before suspend");
1121 EXPORT_SYMBOL_GPL(tpm_pm_suspend);
1124 * Resume from a power safe. The BIOS already restored
1127 int tpm_pm_resume(struct device *dev)
1129 struct tpm_chip *chip = dev_get_drvdata(dev);
1136 EXPORT_SYMBOL_GPL(tpm_pm_resume);
1138 /* In case vendor provided release function, call it too.*/
1140 void tpm_dev_vendor_release(struct tpm_chip *chip)
1142 if (chip->vendor.release)
1143 chip->vendor.release(chip->dev);
1145 clear_bit(chip->dev_num, dev_mask);
1146 kfree(chip->vendor.miscdev.name);
1148 EXPORT_SYMBOL_GPL(tpm_dev_vendor_release);
1152 * Once all references to platform device are down to 0,
1153 * release all allocated structures.
1155 void tpm_dev_release(struct device *dev)
1157 struct tpm_chip *chip = dev_get_drvdata(dev);
1159 tpm_dev_vendor_release(chip);
1164 EXPORT_SYMBOL_GPL(tpm_dev_release);
1167 * Called from tpm_<specific>.c probe function only for devices
1168 * the driver has determined it should claim. Prior to calling
1169 * this function the specific probe function has called pci_enable_device
1170 * upon errant exit from this function specific probe function should call
1171 * pci_disable_device
1173 struct tpm_chip *tpm_register_hardware(struct device *dev,
1174 const struct tpm_vendor_specific *entry)
1176 #define DEVNAME_SIZE 7
1179 struct tpm_chip *chip;
1181 /* Driver specific per-device data */
1182 chip = kzalloc(sizeof(*chip), GFP_KERNEL);
1183 devname = kmalloc(DEVNAME_SIZE, GFP_KERNEL);
1185 if (chip == NULL || devname == NULL)
1188 mutex_init(&chip->buffer_mutex);
1189 mutex_init(&chip->tpm_mutex);
1190 INIT_LIST_HEAD(&chip->list);
1192 INIT_WORK(&chip->work, timeout_work);
1194 setup_timer(&chip->user_read_timer, user_reader_timeout,
1195 (unsigned long)chip);
1197 memcpy(&chip->vendor, entry, sizeof(struct tpm_vendor_specific));
1199 chip->dev_num = find_first_zero_bit(dev_mask, TPM_NUM_DEVICES);
1201 if (chip->dev_num >= TPM_NUM_DEVICES) {
1202 dev_err(dev, "No available tpm device numbers\n");
1204 } else if (chip->dev_num == 0)
1205 chip->vendor.miscdev.minor = TPM_MINOR;
1207 chip->vendor.miscdev.minor = MISC_DYNAMIC_MINOR;
1209 set_bit(chip->dev_num, dev_mask);
1211 scnprintf(devname, DEVNAME_SIZE, "%s%d", "tpm", chip->dev_num);
1212 chip->vendor.miscdev.name = devname;
1214 chip->vendor.miscdev.parent = dev;
1215 chip->dev = get_device(dev);
1216 chip->release = dev->release;
1217 dev->release = tpm_dev_release;
1218 dev_set_drvdata(dev, chip);
1220 if (misc_register(&chip->vendor.miscdev)) {
1222 "unable to misc_register %s, minor %d\n",
1223 chip->vendor.miscdev.name,
1224 chip->vendor.miscdev.minor);
1225 put_device(chip->dev);
1229 if (sysfs_create_group(&dev->kobj, chip->vendor.attr_group)) {
1230 misc_deregister(&chip->vendor.miscdev);
1231 put_device(chip->dev);
1236 chip->bios_dir = tpm_bios_log_setup(devname);
1238 /* Make chip available */
1239 spin_lock(&driver_lock);
1240 list_add_rcu(&chip->list, &tpm_chip_list);
1241 spin_unlock(&driver_lock);
1250 EXPORT_SYMBOL_GPL(tpm_register_hardware);
1252 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1253 MODULE_DESCRIPTION("TPM Driver");
1254 MODULE_VERSION("2.0");
1255 MODULE_LICENSE("GPL");