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tpm: Provide strong locking for device removal
[deliverable/linux.git] / drivers / char / tpm / tpm-interface.c
CommitLineData
1da177e4
LT		 1/*
2 * Copyright (C) 2004 IBM Corporation
afb5abc2 3 * Copyright (C) 2014 Intel Corporation
1da177e4
LT		 4 *
5 * Authors:
6 * Leendert van Doorn <leendert@watson.ibm.com>
7 * Dave Safford <safford@watson.ibm.com>
8 * Reiner Sailer <sailer@watson.ibm.com>
9 * Kylene Hall <kjhall@us.ibm.com>
10 *
8e81cc13 11 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
1da177e4
LT		 12 *
13 * Device driver for TCG/TCPA TPM (trusted platform module).
0a418269 14 * Specifications at www.trustedcomputinggroup.org
1da177e4
LT		 15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation, version 2 of the
19 * License.
0a418269 20 *
1da177e4
LT		 21 * Note, the TPM chip is not interrupt driven (only polling)
22 * and can have very long timeouts (minutes!). Hence the unusual
700d8bdc 23 * calls to msleep.
1da177e4
LT		 24 *
25 */
26
1da177e4 27#include <linux/poll.h>
5a0e3ad6 28#include <linux/slab.h>
d081d470 29#include <linux/mutex.h>
1da177e4 30#include <linux/spinlock.h>
fd048866 31#include <linux/freezer.h>
d081d470 32
1da177e4 33#include "tpm.h"
e5dcd87f 34#include "tpm_eventlog.h"
1da177e4 35
9e18ee19 36#define TPM_MAX_ORDINAL 243
07b133e6
PH		 37#define TSC_MAX_ORDINAL 12
38#define TPM_PROTECTED_COMMAND 0x00
39#define TPM_CONNECTION_COMMAND 0x40
9e18ee19 40
9b3056cc
DT		 41/*
42 * Bug workaround - some TPM's don't flush the most
43 * recently changed pcr on suspend, so force the flush
44 * with an extend to the selected _unused_ non-volatile pcr.
45 */
46static int tpm_suspend_pcr;
47module_param_named(suspend_pcr, tpm_suspend_pcr, uint, 0644);
48MODULE_PARM_DESC(suspend_pcr,
49 "PCR to use for dummy writes to faciltate flush on suspend.");
50
9e18ee19
KJH		 51/*
52 * Array with one entry per ordinal defining the maximum amount
53 * of time the chip could take to return the result. The ordinal
54 * designation of short, medium or long is defined in a table in
55 * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
56 * values of the SHORT, MEDIUM, and LONG durations are retrieved
57 * from the chip during initialization with a call to tpm_get_timeouts.
58 */
9e18ee19
KJH		 59static const u8 tpm_ordinal_duration[TPM_MAX_ORDINAL] = {
60 TPM_UNDEFINED, /* 0 */
61 TPM_UNDEFINED,
62 TPM_UNDEFINED,
63 TPM_UNDEFINED,
64 TPM_UNDEFINED,
65 TPM_UNDEFINED, /* 5 */
66 TPM_UNDEFINED,
67 TPM_UNDEFINED,
68 TPM_UNDEFINED,
69 TPM_UNDEFINED,
70 TPM_SHORT, /* 10 */
71 TPM_SHORT,
72 TPM_MEDIUM,
73 TPM_LONG,
74 TPM_LONG,
75 TPM_MEDIUM, /* 15 */
76 TPM_SHORT,
77 TPM_SHORT,
78 TPM_MEDIUM,
79 TPM_LONG,
80 TPM_SHORT, /* 20 */
81 TPM_SHORT,
82 TPM_MEDIUM,
83 TPM_MEDIUM,
84 TPM_MEDIUM,
85 TPM_SHORT, /* 25 */
86 TPM_SHORT,
87 TPM_MEDIUM,
88 TPM_SHORT,
89 TPM_SHORT,
90 TPM_MEDIUM, /* 30 */
91 TPM_LONG,
92 TPM_MEDIUM,
93 TPM_SHORT,
94 TPM_SHORT,
95 TPM_SHORT, /* 35 */
96 TPM_MEDIUM,
97 TPM_MEDIUM,
98 TPM_UNDEFINED,
99 TPM_UNDEFINED,
100 TPM_MEDIUM, /* 40 */
101 TPM_LONG,
102 TPM_MEDIUM,
103 TPM_SHORT,
104 TPM_SHORT,
105 TPM_SHORT, /* 45 */
106 TPM_SHORT,
107 TPM_SHORT,
108 TPM_SHORT,
109 TPM_LONG,
110 TPM_MEDIUM, /* 50 */
111 TPM_MEDIUM,
112 TPM_UNDEFINED,
113 TPM_UNDEFINED,
114 TPM_UNDEFINED,
115 TPM_UNDEFINED, /* 55 */
116 TPM_UNDEFINED,
117 TPM_UNDEFINED,
118 TPM_UNDEFINED,
119 TPM_UNDEFINED,
120 TPM_MEDIUM, /* 60 */
121 TPM_MEDIUM,
122 TPM_MEDIUM,
123 TPM_SHORT,
124 TPM_SHORT,
125 TPM_MEDIUM, /* 65 */
126 TPM_UNDEFINED,
127 TPM_UNDEFINED,
128 TPM_UNDEFINED,
129 TPM_UNDEFINED,
130 TPM_SHORT, /* 70 */
131 TPM_SHORT,
132 TPM_UNDEFINED,
133 TPM_UNDEFINED,
134 TPM_UNDEFINED,
135 TPM_UNDEFINED, /* 75 */
136 TPM_UNDEFINED,
137 TPM_UNDEFINED,
138 TPM_UNDEFINED,
139 TPM_UNDEFINED,
140 TPM_LONG, /* 80 */
141 TPM_UNDEFINED,
142 TPM_MEDIUM,
143 TPM_LONG,
144 TPM_SHORT,
145 TPM_UNDEFINED, /* 85 */
146 TPM_UNDEFINED,
147 TPM_UNDEFINED,
148 TPM_UNDEFINED,
149 TPM_UNDEFINED,
150 TPM_SHORT, /* 90 */
151 TPM_SHORT,
152 TPM_SHORT,
153 TPM_SHORT,
154 TPM_SHORT,
155 TPM_UNDEFINED, /* 95 */
156 TPM_UNDEFINED,
157 TPM_UNDEFINED,
158 TPM_UNDEFINED,
159 TPM_UNDEFINED,
160 TPM_MEDIUM, /* 100 */
161 TPM_SHORT,
162 TPM_SHORT,
163 TPM_UNDEFINED,
164 TPM_UNDEFINED,
165 TPM_UNDEFINED, /* 105 */
166 TPM_UNDEFINED,
167 TPM_UNDEFINED,
168 TPM_UNDEFINED,
169 TPM_UNDEFINED,
170 TPM_SHORT, /* 110 */
171 TPM_SHORT,
172 TPM_SHORT,
173 TPM_SHORT,
174 TPM_SHORT,
175 TPM_SHORT, /* 115 */
176 TPM_SHORT,
177 TPM_SHORT,
178 TPM_UNDEFINED,
179 TPM_UNDEFINED,
180 TPM_LONG, /* 120 */
181 TPM_LONG,
182 TPM_MEDIUM,
183 TPM_UNDEFINED,
184 TPM_SHORT,
185 TPM_SHORT, /* 125 */
186 TPM_SHORT,
187 TPM_LONG,
188 TPM_SHORT,
189 TPM_SHORT,
190 TPM_SHORT, /* 130 */
191 TPM_MEDIUM,
192 TPM_UNDEFINED,
193 TPM_SHORT,
194 TPM_MEDIUM,
195 TPM_UNDEFINED, /* 135 */
196 TPM_UNDEFINED,
197 TPM_UNDEFINED,
198 TPM_UNDEFINED,
199 TPM_UNDEFINED,
200 TPM_SHORT, /* 140 */
201 TPM_SHORT,
202 TPM_UNDEFINED,
203 TPM_UNDEFINED,
204 TPM_UNDEFINED,
205 TPM_UNDEFINED, /* 145 */
206 TPM_UNDEFINED,
207 TPM_UNDEFINED,
208 TPM_UNDEFINED,
209 TPM_UNDEFINED,
210 TPM_SHORT, /* 150 */
211 TPM_MEDIUM,
212 TPM_MEDIUM,
213 TPM_SHORT,
214 TPM_SHORT,
215 TPM_UNDEFINED, /* 155 */
216 TPM_UNDEFINED,
217 TPM_UNDEFINED,
218 TPM_UNDEFINED,
219 TPM_UNDEFINED,
220 TPM_SHORT, /* 160 */
221 TPM_SHORT,
222 TPM_SHORT,
223 TPM_SHORT,
224 TPM_UNDEFINED,
225 TPM_UNDEFINED, /* 165 */
226 TPM_UNDEFINED,
227 TPM_UNDEFINED,
228 TPM_UNDEFINED,
229 TPM_UNDEFINED,
230 TPM_LONG, /* 170 */
231 TPM_UNDEFINED,
232 TPM_UNDEFINED,
233 TPM_UNDEFINED,
234 TPM_UNDEFINED,
235 TPM_UNDEFINED, /* 175 */
236 TPM_UNDEFINED,
237 TPM_UNDEFINED,
238 TPM_UNDEFINED,
239 TPM_UNDEFINED,
240 TPM_MEDIUM, /* 180 */
241 TPM_SHORT,
242 TPM_MEDIUM,
243 TPM_MEDIUM,
244 TPM_MEDIUM,
245 TPM_MEDIUM, /* 185 */
246 TPM_SHORT,
247 TPM_UNDEFINED,
248 TPM_UNDEFINED,
249 TPM_UNDEFINED,
250 TPM_UNDEFINED, /* 190 */
251 TPM_UNDEFINED,
252 TPM_UNDEFINED,
253 TPM_UNDEFINED,
254 TPM_UNDEFINED,
255 TPM_UNDEFINED, /* 195 */
256 TPM_UNDEFINED,
257 TPM_UNDEFINED,
258 TPM_UNDEFINED,
259 TPM_UNDEFINED,
260 TPM_SHORT, /* 200 */
261 TPM_UNDEFINED,
262 TPM_UNDEFINED,
263 TPM_UNDEFINED,
264 TPM_SHORT,
265 TPM_SHORT, /* 205 */
266 TPM_SHORT,
267 TPM_SHORT,
268 TPM_SHORT,
269 TPM_SHORT,
270 TPM_MEDIUM, /* 210 */
271 TPM_UNDEFINED,
272 TPM_MEDIUM,
273 TPM_MEDIUM,
274 TPM_MEDIUM,
275 TPM_UNDEFINED, /* 215 */
276 TPM_MEDIUM,
277 TPM_UNDEFINED,
278 TPM_UNDEFINED,
279 TPM_SHORT,
280 TPM_SHORT, /* 220 */
281 TPM_SHORT,
282 TPM_SHORT,
283 TPM_SHORT,
284 TPM_SHORT,
285 TPM_UNDEFINED, /* 225 */
286 TPM_UNDEFINED,
287 TPM_UNDEFINED,
288 TPM_UNDEFINED,
289 TPM_UNDEFINED,
290 TPM_SHORT, /* 230 */
291 TPM_LONG,
292 TPM_MEDIUM,
293 TPM_UNDEFINED,
294 TPM_UNDEFINED,
295 TPM_UNDEFINED, /* 235 */
296 TPM_UNDEFINED,
297 TPM_UNDEFINED,
298 TPM_UNDEFINED,
299 TPM_UNDEFINED,
300 TPM_SHORT, /* 240 */
301 TPM_UNDEFINED,
302 TPM_MEDIUM,
303};
304
9e18ee19
KJH		 305/*
306 * Returns max number of jiffies to wait
307 */
308unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
309 u32 ordinal)
310{
311 int duration_idx = TPM_UNDEFINED;
312 int duration = 0;
313
f7286430
MW		 314 /*
315 * We only have a duration table for protected commands, where the upper
316 * 16 bits are 0. For the few other ordinals the fallback will be used.
317 */
318 if (ordinal < TPM_MAX_ORDINAL)
9e18ee19 319 duration_idx = tpm_ordinal_duration[ordinal];
9e18ee19 320
8d1dc20e 321 if (duration_idx != TPM_UNDEFINED)
36b20020 322 duration = chip->vendor.duration[duration_idx];
8d1dc20e 323 if (duration <= 0)
9e18ee19 324 return 2 * 60 * HZ;
8d1dc20e
LT		 325 else
326 return duration;
9e18ee19
KJH		 327}
328EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);
329
1da177e4
LT		 330/*
331 * Internal kernel interface to transmit TPM commands
332 */
afdba32e
JG		 333ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
334 size_t bufsiz)
1da177e4 335{
d9e5b6bf 336 ssize_t rc;
9e18ee19 337 u32 count, ordinal;
700d8bdc 338 unsigned long stop;
1da177e4 339
6b07d30a
PH		 340 if (bufsiz > TPM_BUFSIZE)
341 bufsiz = TPM_BUFSIZE;
342
81179bb6 343 count = be32_to_cpu(*((__be32 *) (buf + 2)));
9e18ee19 344 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
1da177e4
LT		 345 if (count == 0)
346 return -ENODATA;
347 if (count > bufsiz) {
8cfffc9d 348 dev_err(&chip->dev,
0a418269 349 "invalid count value %x %zx\n", count, bufsiz);
1da177e4
LT		 350 return -E2BIG;
351 }
352
d081d470 353 mutex_lock(&chip->tpm_mutex);
1da177e4 354
5f82e9f0 355 rc = chip->ops->send(chip, (u8 *) buf, count);
0a418269 356 if (rc < 0) {
8cfffc9d 357 dev_err(&chip->dev,
d9e5b6bf
KH		 358 "tpm_transmit: tpm_send: error %zd\n", rc);
359 goto out;
1da177e4
LT		 360 }
361
27084efe
LD		 362 if (chip->vendor.irq)
363 goto out_recv;
364
7a1d7e6d
JS		 365 if (chip->flags & TPM_CHIP_FLAG_TPM2)
366 stop = jiffies + tpm2_calc_ordinal_duration(chip, ordinal);
367 else
368 stop = jiffies + tpm_calc_ordinal_duration(chip, ordinal);
1da177e4 369 do {
5f82e9f0
JG		 370 u8 status = chip->ops->status(chip);
371 if ((status & chip->ops->req_complete_mask) ==
372 chip->ops->req_complete_val)
1da177e4 373 goto out_recv;
d9e5b6bf 374
5f82e9f0 375 if (chip->ops->req_canceled(chip, status)) {
8cfffc9d 376 dev_err(&chip->dev, "Operation Canceled\n");
d9e5b6bf
KH		 377 rc = -ECANCELED;
378 goto out;
379 }
380
381 msleep(TPM_TIMEOUT); /* CHECK */
1da177e4 382 rmb();
700d8bdc 383 } while (time_before(jiffies, stop));
1da177e4 384
5f82e9f0 385 chip->ops->cancel(chip);
8cfffc9d 386 dev_err(&chip->dev, "Operation Timed out\n");
d9e5b6bf
KH		 387 rc = -ETIME;
388 goto out;
1da177e4
LT		 389
390out_recv:
5f82e9f0 391 rc = chip->ops->recv(chip, (u8 *) buf, bufsiz);
d9e5b6bf 392 if (rc < 0)
8cfffc9d 393 dev_err(&chip->dev,
d9e5b6bf
KH		 394 "tpm_transmit: tpm_recv: error %zd\n", rc);
395out:
d081d470 396 mutex_unlock(&chip->tpm_mutex);
d9e5b6bf 397 return rc;
1da177e4
LT		 398}
399
400#define TPM_DIGEST_SIZE 20
beed53a1 401#define TPM_RET_CODE_IDX 6
beed53a1 402
87155b73
JS		 403ssize_t tpm_transmit_cmd(struct tpm_chip *chip, void *cmd,
404 int len, const char *desc)
beed53a1 405{
87155b73 406 struct tpm_output_header *header;
beed53a1
KJH		 407 int err;
408
0a418269 409 len = tpm_transmit(chip, (u8 *) cmd, len);
beed53a1
KJH		 410 if (len < 0)
411 return len;
b9e3238a
RA		 412 else if (len < TPM_HEADER_SIZE)
413 return -EFAULT;
414
87155b73
JS		 415 header = cmd;
416
417 err = be32_to_cpu(header->return_code);
c584af19 418 if (err != 0 && desc)
8cfffc9d 419 dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err,
71ed848f 420 desc);
b9e3238a
RA		 421
422 return err;
beed53a1
KJH		 423}
424
08837438 425#define TPM_INTERNAL_RESULT_SIZE 200
08837438 426#define TPM_ORD_GET_CAP cpu_to_be32(101)
41ab999c 427#define TPM_ORD_GET_RANDOM cpu_to_be32(70)
08837438
RA		 428
429static const struct tpm_input_header tpm_getcap_header = {
430 .tag = TPM_TAG_RQU_COMMAND,
431 .length = cpu_to_be32(22),
432 .ordinal = TPM_ORD_GET_CAP
433};
434
435ssize_t tpm_getcap(struct device *dev, __be32 subcap_id, cap_t *cap,
436 const char *desc)
437{
438 struct tpm_cmd_t tpm_cmd;
439 int rc;
440 struct tpm_chip *chip = dev_get_drvdata(dev);
441
442 tpm_cmd.header.in = tpm_getcap_header;
443 if (subcap_id == CAP_VERSION_1_1 || subcap_id == CAP_VERSION_1_2) {
444 tpm_cmd.params.getcap_in.cap = subcap_id;
445 /*subcap field not necessary */
446 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(0);
447 tpm_cmd.header.in.length -= cpu_to_be32(sizeof(__be32));
448 } else {
449 if (subcap_id == TPM_CAP_FLAG_PERM ||
450 subcap_id == TPM_CAP_FLAG_VOL)
451 tpm_cmd.params.getcap_in.cap = TPM_CAP_FLAG;
452 else
453 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
454 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
455 tpm_cmd.params.getcap_in.subcap = subcap_id;
456 }
87155b73 457 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, desc);
08837438
RA		 458 if (!rc)
459 *cap = tpm_cmd.params.getcap_out.cap;
460 return rc;
461}
462
08e96e48
KJH		 463void tpm_gen_interrupt(struct tpm_chip *chip)
464{
08837438 465 struct tpm_cmd_t tpm_cmd;
08e96e48
KJH		 466 ssize_t rc;
467
08837438
RA		 468 tpm_cmd.header.in = tpm_getcap_header;
469 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
470 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
471 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
08e96e48 472
87155b73
JS		 473 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
474 "attempting to determine the timeouts");
08e96e48
KJH		 475}
476EXPORT_SYMBOL_GPL(tpm_gen_interrupt);
477
c584af19
JG		 478#define TPM_ORD_STARTUP cpu_to_be32(153)
479#define TPM_ST_CLEAR cpu_to_be16(1)
480#define TPM_ST_STATE cpu_to_be16(2)
481#define TPM_ST_DEACTIVATED cpu_to_be16(3)
482static const struct tpm_input_header tpm_startup_header = {
483 .tag = TPM_TAG_RQU_COMMAND,
484 .length = cpu_to_be32(12),
485 .ordinal = TPM_ORD_STARTUP
486};
487
488static int tpm_startup(struct tpm_chip *chip, __be16 startup_type)
489{
490 struct tpm_cmd_t start_cmd;
491 start_cmd.header.in = tpm_startup_header;
7a1d7e6d 492
c584af19 493 start_cmd.params.startup_in.startup_type = startup_type;
87155b73
JS		 494 return tpm_transmit_cmd(chip, &start_cmd, TPM_INTERNAL_RESULT_SIZE,
495 "attempting to start the TPM");
c584af19
JG		 496}
497
2b30a90f 498int tpm_get_timeouts(struct tpm_chip *chip)
08e96e48 499{
08837438 500 struct tpm_cmd_t tpm_cmd;
8e54caf4
JG		 501 unsigned long new_timeout[4];
502 unsigned long old_timeout[4];
08837438 503 struct duration_t *duration_cap;
08e96e48 504 ssize_t rc;
08e96e48 505
25112048
JG		 506 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
507 /* Fixed timeouts for TPM2 */
508 chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
509 chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
510 chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
511 chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
512 chip->vendor.duration[TPM_SHORT] =
513 msecs_to_jiffies(TPM2_DURATION_SHORT);
514 chip->vendor.duration[TPM_MEDIUM] =
515 msecs_to_jiffies(TPM2_DURATION_MEDIUM);
516 chip->vendor.duration[TPM_LONG] =
517 msecs_to_jiffies(TPM2_DURATION_LONG);
518 return 0;
519 }
520
08837438
RA		 521 tpm_cmd.header.in = tpm_getcap_header;
522 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
523 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
524 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
87155b73 525 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE, NULL);
08e96e48 526
c584af19
JG		 527 if (rc == TPM_ERR_INVALID_POSTINIT) {
528 /* The TPM is not started, we are the first to talk to it.
529 Execute a startup command. */
8cfffc9d 530 dev_info(&chip->dev, "Issuing TPM_STARTUP");
c584af19
JG		 531 if (tpm_startup(chip, TPM_ST_CLEAR))
532 return rc;
533
534 tpm_cmd.header.in = tpm_getcap_header;
535 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
536 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
537 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_TIMEOUT;
87155b73 538 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
c584af19
JG		 539 NULL);
540 }
541 if (rc) {
8cfffc9d 542 dev_err(&chip->dev,
c584af19
JG		 543 "A TPM error (%zd) occurred attempting to determine the timeouts\n",
544 rc);
08e96e48 545 goto duration;
c584af19 546 }
08e96e48 547
829bf067
SB		 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))
2b30a90f 551 return -EINVAL;
08e96e48 552
8e54caf4
JG		 553 old_timeout[0] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.a);
554 old_timeout[1] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.b);
555 old_timeout[2] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.c);
556 old_timeout[3] = be32_to_cpu(tpm_cmd.params.getcap_out.cap.timeout.d);
557 memcpy(new_timeout, old_timeout, sizeof(new_timeout));
558
559 /*
560 * Provide ability for vendor overrides of timeout values in case
561 * of misreporting.
562 */
563 if (chip->ops->update_timeouts != NULL)
564 chip->vendor.timeout_adjusted =
565 chip->ops->update_timeouts(chip, new_timeout);
566
567 if (!chip->vendor.timeout_adjusted) {
568 /* Don't overwrite default if value is 0 */
569 if (new_timeout[0] != 0 && new_timeout[0] < 1000) {
570 int i;
571
572 /* timeouts in msec rather usec */
573 for (i = 0; i != ARRAY_SIZE(new_timeout); i++)
574 new_timeout[i] *= 1000;
575 chip->vendor.timeout_adjusted = true;
576 }
577 }
578
579 /* Report adjusted timeouts */
580 if (chip->vendor.timeout_adjusted) {
8cfffc9d 581 dev_info(&chip->dev,
8e54caf4
JG		 582 HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
583 old_timeout[0], new_timeout[0],
584 old_timeout[1], new_timeout[1],
585 old_timeout[2], new_timeout[2],
586 old_timeout[3], new_timeout[3]);
e3e1a1e1 587 }
8e54caf4
JG		 588
589 chip->vendor.timeout_a = usecs_to_jiffies(new_timeout[0]);
590 chip->vendor.timeout_b = usecs_to_jiffies(new_timeout[1]);
591 chip->vendor.timeout_c = usecs_to_jiffies(new_timeout[2]);
592 chip->vendor.timeout_d = usecs_to_jiffies(new_timeout[3]);
08e96e48
KJH		 593
594duration:
08837438
RA		 595 tpm_cmd.header.in = tpm_getcap_header;
596 tpm_cmd.params.getcap_in.cap = TPM_CAP_PROP;
597 tpm_cmd.params.getcap_in.subcap_size = cpu_to_be32(4);
598 tpm_cmd.params.getcap_in.subcap = TPM_CAP_PROP_TIS_DURATION;
08e96e48 599
87155b73
JS		 600 rc = tpm_transmit_cmd(chip, &tpm_cmd, TPM_INTERNAL_RESULT_SIZE,
601 "attempting to determine the durations");
08e96e48 602 if (rc)
2b30a90f 603 return rc;
08e96e48 604
979b1406
SB		 605 if (be32_to_cpu(tpm_cmd.header.out.return_code) != 0 ||
606 be32_to_cpu(tpm_cmd.header.out.length)
607 != sizeof(tpm_cmd.header.out) + sizeof(u32) + 3 * sizeof(u32))
2b30a90f 608 return -EINVAL;
979b1406 609
08837438 610 duration_cap = &tpm_cmd.params.getcap_out.cap.duration;
08e96e48 611 chip->vendor.duration[TPM_SHORT] =
08837438 612 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_short));
e934acca
SB		 613 chip->vendor.duration[TPM_MEDIUM] =
614 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_medium));
615 chip->vendor.duration[TPM_LONG] =
616 usecs_to_jiffies(be32_to_cpu(duration_cap->tpm_long));
617
292cf4a8
VK		 618 /* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
619 * value wrong and apparently reports msecs rather than usecs. So we
620 * fix up the resulting too-small TPM_SHORT value to make things work.
e934acca 621 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
292cf4a8 622 */
e934acca 623 if (chip->vendor.duration[TPM_SHORT] < (HZ / 100)) {
292cf4a8 624 chip->vendor.duration[TPM_SHORT] = HZ;
e934acca
SB		 625 chip->vendor.duration[TPM_MEDIUM] *= 1000;
626 chip->vendor.duration[TPM_LONG] *= 1000;
04ab2293 627 chip->vendor.duration_adjusted = true;
8cfffc9d 628 dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
e934acca 629 }
2b30a90f 630 return 0;
08e96e48
KJH		 631}
632EXPORT_SYMBOL_GPL(tpm_get_timeouts);
633
d97c6ade
SB		 634#define TPM_ORD_CONTINUE_SELFTEST 83
635#define CONTINUE_SELFTEST_RESULT_SIZE 10
636
637static struct tpm_input_header continue_selftest_header = {
638 .tag = TPM_TAG_RQU_COMMAND,
639 .length = cpu_to_be32(10),
640 .ordinal = cpu_to_be32(TPM_ORD_CONTINUE_SELFTEST),
641};
642
643/**
644 * tpm_continue_selftest -- run TPM's selftest
645 * @chip: TPM chip to use
646 *
647 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
648 * a TPM error code.
649 */
68d6e671 650static int tpm_continue_selftest(struct tpm_chip *chip)
08e96e48 651{
d97c6ade
SB		 652 int rc;
653 struct tpm_cmd_t cmd;
08e96e48 654
d97c6ade 655 cmd.header.in = continue_selftest_header;
87155b73
JS		 656 rc = tpm_transmit_cmd(chip, &cmd, CONTINUE_SELFTEST_RESULT_SIZE,
657 "continue selftest");
d97c6ade 658 return rc;
08e96e48 659}
08e96e48 660
659aaf2b
RA		 661#define TPM_ORDINAL_PCRREAD cpu_to_be32(21)
662#define READ_PCR_RESULT_SIZE 30
663static struct tpm_input_header pcrread_header = {
664 .tag = TPM_TAG_RQU_COMMAND,
665 .length = cpu_to_be32(14),
666 .ordinal = TPM_ORDINAL_PCRREAD
1da177e4
LT		 667};
668
000a07b0 669int tpm_pcr_read_dev(struct tpm_chip *chip, int pcr_idx, u8 *res_buf)
659aaf2b
RA		 670{
671 int rc;
672 struct tpm_cmd_t cmd;
673
674 cmd.header.in = pcrread_header;
675 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(pcr_idx);
87155b73
JS		 676 rc = tpm_transmit_cmd(chip, &cmd, READ_PCR_RESULT_SIZE,
677 "attempting to read a pcr value");
659aaf2b
RA		 678
679 if (rc == 0)
680 memcpy(res_buf, cmd.params.pcrread_out.pcr_result,
681 TPM_DIGEST_SIZE);
682 return rc;
683}
684
954650ef
JS		 685/**
686 * tpm_is_tpm2 - is the chip a TPM2 chip?
687 * @chip_num: tpm idx # or ANY
688 *
689 * Returns < 0 on error, and 1 or 0 on success depending whether the chip
690 * is a TPM2 chip.
691 */
692int tpm_is_tpm2(u32 chip_num)
693{
694 struct tpm_chip *chip;
695 int rc;
696
697 chip = tpm_chip_find_get(chip_num);
698 if (chip == NULL)
699 return -ENODEV;
700
701 rc = (chip->flags & TPM_CHIP_FLAG_TPM2) != 0;
702
4e26195f 703 tpm_put_ops(chip);
954650ef
JS		 704
705 return rc;
706}
707EXPORT_SYMBOL_GPL(tpm_is_tpm2);
708
659aaf2b
RA		 709/**
710 * tpm_pcr_read - read a pcr value
0a418269 711 * @chip_num: tpm idx # or ANY
659aaf2b 712 * @pcr_idx: pcr idx to retrieve
0a418269
PH		 713 * @res_buf: TPM_PCR value
714 * size of res_buf is 20 bytes (or NULL if you don't care)
659aaf2b
RA		 715 *
716 * The TPM driver should be built-in, but for whatever reason it
717 * isn't, protect against the chip disappearing, by incrementing
718 * the module usage count.
719 */
720int tpm_pcr_read(u32 chip_num, int pcr_idx, u8 *res_buf)
721{
722 struct tpm_chip *chip;
723 int rc;
724
725 chip = tpm_chip_find_get(chip_num);
726 if (chip == NULL)
727 return -ENODEV;
7a1d7e6d
JS		 728 if (chip->flags & TPM_CHIP_FLAG_TPM2)
729 rc = tpm2_pcr_read(chip, pcr_idx, res_buf);
730 else
731 rc = tpm_pcr_read_dev(chip, pcr_idx, res_buf);
4e26195f 732 tpm_put_ops(chip);
659aaf2b
RA		 733 return rc;
734}
735EXPORT_SYMBOL_GPL(tpm_pcr_read);
736
737/**
738 * tpm_pcr_extend - extend pcr value with hash
0a418269 739 * @chip_num: tpm idx # or AN&
659aaf2b 740 * @pcr_idx: pcr idx to extend
0a418269 741 * @hash: hash value used to extend pcr value
659aaf2b
RA		 742 *
743 * The TPM driver should be built-in, but for whatever reason it
744 * isn't, protect against the chip disappearing, by incrementing
745 * the module usage count.
746 */
747#define TPM_ORD_PCR_EXTEND cpu_to_be32(20)
0afd9056 748#define EXTEND_PCR_RESULT_SIZE 34
659aaf2b
RA		 749static struct tpm_input_header pcrextend_header = {
750 .tag = TPM_TAG_RQU_COMMAND,
751 .length = cpu_to_be32(34),
752 .ordinal = TPM_ORD_PCR_EXTEND
753};
754
755int tpm_pcr_extend(u32 chip_num, int pcr_idx, const u8 *hash)
756{
757 struct tpm_cmd_t cmd;
758 int rc;
759 struct tpm_chip *chip;
760
761 chip = tpm_chip_find_get(chip_num);
762 if (chip == NULL)
763 return -ENODEV;
764
7a1d7e6d
JS		 765 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
766 rc = tpm2_pcr_extend(chip, pcr_idx, hash);
4e26195f 767 tpm_put_ops(chip);
7a1d7e6d
JS		 768 return rc;
769 }
770
659aaf2b 771 cmd.header.in = pcrextend_header;
659aaf2b
RA		 772 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(pcr_idx);
773 memcpy(cmd.params.pcrextend_in.hash, hash, TPM_DIGEST_SIZE);
87155b73
JS		 774 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
775 "attempting extend a PCR value");
659aaf2b 776
4e26195f 777 tpm_put_ops(chip);
659aaf2b
RA		 778 return rc;
779}
780EXPORT_SYMBOL_GPL(tpm_pcr_extend);
781
68d6e671
SB		 782/**
783 * tpm_do_selftest - have the TPM continue its selftest and wait until it
784 * can receive further commands
785 * @chip: TPM chip to use
786 *
787 * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
788 * a TPM error code.
789 */
790int tpm_do_selftest(struct tpm_chip *chip)
791{
792 int rc;
68d6e671 793 unsigned int loops;
4643826a 794 unsigned int delay_msec = 100;
68d6e671 795 unsigned long duration;
24ebe667 796 struct tpm_cmd_t cmd;
68d6e671 797
0a418269 798 duration = tpm_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
68d6e671
SB		 799
800 loops = jiffies_to_msecs(duration) / delay_msec;
801
802 rc = tpm_continue_selftest(chip);
803 /* This may fail if there was no TPM driver during a suspend/resume
804 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
805 */
806 if (rc)
807 return rc;
808
809 do {
24ebe667
RA		 810 /* Attempt to read a PCR value */
811 cmd.header.in = pcrread_header;
812 cmd.params.pcrread_in.pcr_idx = cpu_to_be32(0);
813 rc = tpm_transmit(chip, (u8 *) &cmd, READ_PCR_RESULT_SIZE);
4643826a
JG		 814 /* Some buggy TPMs will not respond to tpm_tis_ready() for
815 * around 300ms while the self test is ongoing, keep trying
816 * until the self test duration expires. */
817 if (rc == -ETIME) {
8cfffc9d
JG		 818 dev_info(
819 &chip->dev, HW_ERR
820 "TPM command timed out during continue self test");
4643826a
JG		 821 msleep(delay_msec);
822 continue;
823 }
24ebe667
RA		 824
825 if (rc < TPM_HEADER_SIZE)
826 return -EFAULT;
827
828 rc = be32_to_cpu(cmd.header.out.return_code);
be405411 829 if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
8cfffc9d 830 dev_info(&chip->dev,
be405411
SB		 831 "TPM is disabled/deactivated (0x%X)\n", rc);
832 /* TPM is disabled and/or deactivated; driver can
833 * proceed and TPM does handle commands for
834 * suspend/resume correctly
835 */
836 return 0;
837 }
68d6e671
SB		 838 if (rc != TPM_WARN_DOING_SELFTEST)
839 return rc;
840 msleep(delay_msec);
841 } while (--loops > 0);
842
843 return rc;
844}
845EXPORT_SYMBOL_GPL(tpm_do_selftest);
846
c749ba91
MZ		 847int tpm_send(u32 chip_num, void *cmd, size_t buflen)
848{
849 struct tpm_chip *chip;
850 int rc;
851
852 chip = tpm_chip_find_get(chip_num);
853 if (chip == NULL)
854 return -ENODEV;
855
87155b73 856 rc = tpm_transmit_cmd(chip, cmd, buflen, "attempting tpm_cmd");
c749ba91 857
4e26195f 858 tpm_put_ops(chip);
c749ba91
MZ		 859 return rc;
860}
861EXPORT_SYMBOL_GPL(tpm_send);
862
0a418269
PH		 863static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
864 bool check_cancel, bool *canceled)
78f09cc2 865{
5f82e9f0 866 u8 status = chip->ops->status(chip);
78f09cc2
SB		 867
868 *canceled = false;
869 if ((status & mask) == mask)
870 return true;
5f82e9f0 871 if (check_cancel && chip->ops->req_canceled(chip, status)) {
78f09cc2
SB		 872 *canceled = true;
873 return true;
874 }
875 return false;
876}
877
fd048866 878int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
78f09cc2 879 wait_queue_head_t *queue, bool check_cancel)
fd048866
RA		 880{
881 unsigned long stop;
882 long rc;
883 u8 status;
78f09cc2 884 bool canceled = false;
fd048866
RA		 885
886 /* check current status */
5f82e9f0 887 status = chip->ops->status(chip);
fd048866
RA		 888 if ((status & mask) == mask)
889 return 0;
890
891 stop = jiffies + timeout;
892
893 if (chip->vendor.irq) {
894again:
895 timeout = stop - jiffies;
896 if ((long)timeout <= 0)
897 return -ETIME;
898 rc = wait_event_interruptible_timeout(*queue,
78f09cc2
SB		 899 wait_for_tpm_stat_cond(chip, mask, check_cancel,
900 &canceled),
901 timeout);
902 if (rc > 0) {
903 if (canceled)
904 return -ECANCELED;
fd048866 905 return 0;
78f09cc2 906 }
fd048866
RA		 907 if (rc == -ERESTARTSYS && freezing(current)) {
908 clear_thread_flag(TIF_SIGPENDING);
909 goto again;
910 }
911 } else {
912 do {
913 msleep(TPM_TIMEOUT);
5f82e9f0 914 status = chip->ops->status(chip);
fd048866
RA		 915 if ((status & mask) == mask)
916 return 0;
917 } while (time_before(jiffies, stop));
918 }
919 return -ETIME;
920}
921EXPORT_SYMBOL_GPL(wait_for_tpm_stat);
1da177e4 922
225a9be2
RA		 923#define TPM_ORD_SAVESTATE cpu_to_be32(152)
924#define SAVESTATE_RESULT_SIZE 10
925
926static struct tpm_input_header savestate_header = {
927 .tag = TPM_TAG_RQU_COMMAND,
928 .length = cpu_to_be32(10),
929 .ordinal = TPM_ORD_SAVESTATE
930};
931
1da177e4
LT		 932/*
933 * We are about to suspend. Save the TPM state
934 * so that it can be restored.
935 */
035e2ce8 936int tpm_pm_suspend(struct device *dev)
1da177e4 937{
ce2c87d4 938 struct tpm_chip *chip = dev_get_drvdata(dev);
225a9be2 939 struct tpm_cmd_t cmd;
32d33b29 940 int rc, try;
225a9be2
RA		 941
942 u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
2490c681 943
1da177e4
LT		 944 if (chip == NULL)
945 return -ENODEV;
946
74d6b3ce
JS		 947 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
948 tpm2_shutdown(chip, TPM2_SU_STATE);
949 return 0;
950 }
30fc8d13 951
225a9be2
RA		 952 /* for buggy tpm, flush pcrs with extend to selected dummy */
953 if (tpm_suspend_pcr) {
954 cmd.header.in = pcrextend_header;
955 cmd.params.pcrextend_in.pcr_idx = cpu_to_be32(tpm_suspend_pcr);
956 memcpy(cmd.params.pcrextend_in.hash, dummy_hash,
957 TPM_DIGEST_SIZE);
87155b73
JS		 958 rc = tpm_transmit_cmd(chip, &cmd, EXTEND_PCR_RESULT_SIZE,
959 "extending dummy pcr before suspend");
225a9be2
RA		 960 }
961
962 /* now do the actual savestate */
32d33b29
DL		 963 for (try = 0; try < TPM_RETRY; try++) {
964 cmd.header.in = savestate_header;
87155b73 965 rc = tpm_transmit_cmd(chip, &cmd, SAVESTATE_RESULT_SIZE, NULL);
32d33b29
DL		 966
967 /*
968 * If the TPM indicates that it is too busy to respond to
969 * this command then retry before giving up. It can take
970 * several seconds for this TPM to be ready.
971 *
972 * This can happen if the TPM has already been sent the
973 * SaveState command before the driver has loaded. TCG 1.2
974 * specification states that any communication after SaveState
975 * may cause the TPM to invalidate previously saved state.
976 */
977 if (rc != TPM_WARN_RETRY)
978 break;
979 msleep(TPM_TIMEOUT_RETRY);
980 }
981
982 if (rc)
8cfffc9d 983 dev_err(&chip->dev,
32d33b29
DL		 984 "Error (%d) sending savestate before suspend\n", rc);
985 else if (try > 0)
8cfffc9d 986 dev_warn(&chip->dev, "TPM savestate took %dms\n",
32d33b29
DL		 987 try * TPM_TIMEOUT_RETRY);
988
225a9be2 989 return rc;
1da177e4 990}
1da177e4
LT		 991EXPORT_SYMBOL_GPL(tpm_pm_suspend);
992
993/*
994 * Resume from a power safe. The BIOS already restored
995 * the TPM state.
996 */
ce2c87d4 997int tpm_pm_resume(struct device *dev)
1da177e4 998{
ce2c87d4 999 struct tpm_chip *chip = dev_get_drvdata(dev);
1da177e4
LT		 1000
1001 if (chip == NULL)
1002 return -ENODEV;
1003
1da177e4
LT		 1004 return 0;
1005}
1da177e4
LT		 1006EXPORT_SYMBOL_GPL(tpm_pm_resume);
1007
41ab999c
KY		 1008#define TPM_GETRANDOM_RESULT_SIZE 18
1009static struct tpm_input_header tpm_getrandom_header = {
1010 .tag = TPM_TAG_RQU_COMMAND,
1011 .length = cpu_to_be32(14),
1012 .ordinal = TPM_ORD_GET_RANDOM
1013};
1014
1015/**
1016 * tpm_get_random() - Get random bytes from the tpm's RNG
1017 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1018 * @out: destination buffer for the random bytes
1019 * @max: the max number of bytes to write to @out
1020 *
1021 * Returns < 0 on error and the number of bytes read on success
1022 */
1023int tpm_get_random(u32 chip_num, u8 *out, size_t max)
1024{
1025 struct tpm_chip *chip;
1026 struct tpm_cmd_t tpm_cmd;
1027 u32 recd, num_bytes = min_t(u32, max, TPM_MAX_RNG_DATA);
1028 int err, total = 0, retries = 5;
1029 u8 *dest = out;
1030
3e14d83e
JS		 1031 if (!out || !num_bytes || max > TPM_MAX_RNG_DATA)
1032 return -EINVAL;
1033
41ab999c
KY		 1034 chip = tpm_chip_find_get(chip_num);
1035 if (chip == NULL)
1036 return -ENODEV;
1037
7a1d7e6d
JS		 1038 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
1039 err = tpm2_get_random(chip, out, max);
4e26195f 1040 tpm_put_ops(chip);
7a1d7e6d
JS		 1041 return err;
1042 }
1043
41ab999c
KY		 1044 do {
1045 tpm_cmd.header.in = tpm_getrandom_header;
1046 tpm_cmd.params.getrandom_in.num_bytes = cpu_to_be32(num_bytes);
1047
87155b73 1048 err = tpm_transmit_cmd(chip, &tpm_cmd,
41ab999c
KY		 1049 TPM_GETRANDOM_RESULT_SIZE + num_bytes,
1050 "attempting get random");
1051 if (err)
1052 break;
1053
1054 recd = be32_to_cpu(tpm_cmd.params.getrandom_out.rng_data_len);
1055 memcpy(dest, tpm_cmd.params.getrandom_out.rng_data, recd);
1056
1057 dest += recd;
1058 total += recd;
1059 num_bytes -= recd;
1060 } while (retries-- && total < max);
1061
4e26195f 1062 tpm_put_ops(chip);
41ab999c
KY		 1063 return total ? total : -EIO;
1064}
1065EXPORT_SYMBOL_GPL(tpm_get_random);
1066
954650ef
JS		 1067/**
1068 * tpm_seal_trusted() - seal a trusted key
1069 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1070 * @options: authentication values and other options
1071 * @payload: the key data in clear and encrypted form
1072 *
1073 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1074 * are supported.
1075 */
1076int tpm_seal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1077 struct trusted_key_options *options)
1078{
1079 struct tpm_chip *chip;
1080 int rc;
1081
1082 chip = tpm_chip_find_get(chip_num);
1083 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1084 return -ENODEV;
1085
1086 rc = tpm2_seal_trusted(chip, payload, options);
1087
4e26195f 1088 tpm_put_ops(chip);
954650ef
JS		 1089 return rc;
1090}
1091EXPORT_SYMBOL_GPL(tpm_seal_trusted);
1092
1093/**
1094 * tpm_unseal_trusted() - unseal a trusted key
1095 * @chip_num: A specific chip number for the request or TPM_ANY_NUM
1096 * @options: authentication values and other options
1097 * @payload: the key data in clear and encrypted form
1098 *
1099 * Returns < 0 on error and 0 on success. At the moment, only TPM 2.0 chips
1100 * are supported.
1101 */
1102int tpm_unseal_trusted(u32 chip_num, struct trusted_key_payload *payload,
1103 struct trusted_key_options *options)
1104{
1105 struct tpm_chip *chip;
1106 int rc;
1107
1108 chip = tpm_chip_find_get(chip_num);
1109 if (chip == NULL || !(chip->flags & TPM_CHIP_FLAG_TPM2))
1110 return -ENODEV;
1111
1112 rc = tpm2_unseal_trusted(chip, payload, options);
1113
4e26195f
JG		 1114 tpm_put_ops(chip);
1115
954650ef
JS		 1116 return rc;
1117}
1118EXPORT_SYMBOL_GPL(tpm_unseal_trusted);
1119
313d21ee
JS		 1120static int __init tpm_init(void)
1121{
1122 int rc;
1123
1124 tpm_class = class_create(THIS_MODULE, "tpm");
1125 if (IS_ERR(tpm_class)) {
1126 pr_err("couldn't create tpm class\n");
1127 return PTR_ERR(tpm_class);
1128 }
1129
1130 rc = alloc_chrdev_region(&tpm_devt, 0, TPM_NUM_DEVICES, "tpm");
1131 if (rc < 0) {
1132 pr_err("tpm: failed to allocate char dev region\n");
1133 class_destroy(tpm_class);
1134 return rc;
1135 }
1136
1137 return 0;
1138}
1139
1140static void __exit tpm_exit(void)
1141{
1142 class_destroy(tpm_class);
1143 unregister_chrdev_region(tpm_devt, TPM_NUM_DEVICES);
1144}
1145
1146subsys_initcall(tpm_init);
1147module_exit(tpm_exit);
1148
1da177e4
LT		 1149MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1150MODULE_DESCRIPTION("TPM Driver");
1151MODULE_VERSION("2.0");
1152MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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