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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012,2013 Infineon Technologies
4 *
5 * Authors:
6 * Peter Huewe <peter.huewe@infineon.com>
7 *
8 * Device driver for TCG/TCPA TPM (trusted platform module).
9 * Specifications at www.trustedcomputinggroup.org
10 *
11 * This device driver implements the TPM interface as defined in
12 * the TCG TPM Interface Spec version 1.2, revision 1.0 and the
13 * Infineon I2C Protocol Stack Specification v0.20.
14 *
15 * It is based on the original tpm_tis device driver from Leendert van
16 * Dorn and Kyleen Hall.
17 */
18#include <linux/i2c.h>
19#include <linux/module.h>
20#include <linux/wait.h>
21#include "tpm.h"
22
23#define TPM_I2C_INFINEON_BUFSIZE 1260
24
25/* max. number of iterations after I2C NAK */
26#define MAX_COUNT 3
27
28#define SLEEP_DURATION_LOW 55
29#define SLEEP_DURATION_HI 65
30
31/* max. number of iterations after I2C NAK for 'long' commands
32 * we need this especially for sending TPM_READY, since the cleanup after the
33 * transtion to the ready state may take some time, but it is unpredictable
34 * how long it will take.
35 */
36#define MAX_COUNT_LONG 50
37
38#define SLEEP_DURATION_LONG_LOW 200
39#define SLEEP_DURATION_LONG_HI 220
40
41/* After sending TPM_READY to 'reset' the TPM we have to sleep even longer */
42#define SLEEP_DURATION_RESET_LOW 2400
43#define SLEEP_DURATION_RESET_HI 2600
44
45/* we want to use usleep_range instead of msleep for the 5ms TPM_TIMEOUT */
46#define TPM_TIMEOUT_US_LOW (TPM_TIMEOUT * 1000)
47#define TPM_TIMEOUT_US_HI (TPM_TIMEOUT_US_LOW + 2000)
48
49/* expected value for DIDVID register */
50#define TPM_TIS_I2C_DID_VID_9635 0xd1150b00L
51#define TPM_TIS_I2C_DID_VID_9645 0x001a15d1L
52
53enum i2c_chip_type {
54 SLB9635,
55 SLB9645,
56 UNKNOWN,
57};
58
59struct tpm_inf_dev {
60 struct i2c_client *client;
61 int locality;
62 /* In addition to the data itself, the buffer must fit the 7-bit I2C
63 * address and the direction bit.
64 */
65 u8 buf[TPM_I2C_INFINEON_BUFSIZE + 1];
66 struct tpm_chip *chip;
67 enum i2c_chip_type chip_type;
68 unsigned int adapterlimit;
69};
70
71static struct tpm_inf_dev tpm_dev;
72
73/*
74 * iic_tpm_read() - read from TPM register
75 * @addr: register address to read from
76 * @buffer: provided by caller
77 * @len: number of bytes to read
78 *
79 * Read len bytes from TPM register and put them into
80 * buffer (little-endian format, i.e. first byte is put into buffer[0]).
81 *
82 * NOTE: TPM is big-endian for multi-byte values. Multi-byte
83 * values have to be swapped.
84 *
85 * NOTE: We can't unfortunately use the combined read/write functions
86 * provided by the i2c core as the TPM currently does not support the
87 * repeated start condition and due to it's special requirements.
88 * The i2c_smbus* functions do not work for this chip.
89 *
90 * Return -EIO on error, 0 on success.
91 */
92static int iic_tpm_read(u8 addr, u8 *buffer, size_t len)
93{
94
95 struct i2c_msg msg1 = {
96 .addr = tpm_dev.client->addr,
97 .len = 1,
98 .buf = &addr
99 };
100 struct i2c_msg msg2 = {
101 .addr = tpm_dev.client->addr,
102 .flags = I2C_M_RD,
103 .len = len,
104 .buf = buffer
105 };
106 struct i2c_msg msgs[] = {msg1, msg2};
107
108 int rc = 0;
109 int count;
110 unsigned int msglen = len;
111
112 /* Lock the adapter for the duration of the whole sequence. */
113 if (!tpm_dev.client->adapter->algo->master_xfer)
114 return -EOPNOTSUPP;
115 i2c_lock_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT);
116
117 if (tpm_dev.chip_type == SLB9645) {
118 /* use a combined read for newer chips
119 * unfortunately the smbus functions are not suitable due to
120 * the 32 byte limit of the smbus.
121 * retries should usually not be needed, but are kept just to
122 * be on the safe side.
123 */
124 for (count = 0; count < MAX_COUNT; count++) {
125 rc = __i2c_transfer(tpm_dev.client->adapter, msgs, 2);
126 if (rc > 0)
127 break; /* break here to skip sleep */
128 usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
129 }
130 } else {
131 /* Expect to send one command message and one data message, but
132 * support looping over each or both if necessary.
133 */
134 while (len > 0) {
135 /* slb9635 protocol should work in all cases */
136 for (count = 0; count < MAX_COUNT; count++) {
137 rc = __i2c_transfer(tpm_dev.client->adapter,
138 &msg1, 1);
139 if (rc > 0)
140 break; /* break here to skip sleep */
141
142 usleep_range(SLEEP_DURATION_LOW,
143 SLEEP_DURATION_HI);
144 }
145
146 if (rc <= 0)
147 goto out;
148
149 /* After the TPM has successfully received the register
150 * address it needs some time, thus we're sleeping here
151 * again, before retrieving the data
152 */
153 for (count = 0; count < MAX_COUNT; count++) {
154 if (tpm_dev.adapterlimit) {
155 msglen = min_t(unsigned int,
156 tpm_dev.adapterlimit,
157 len);
158 msg2.len = msglen;
159 }
160 usleep_range(SLEEP_DURATION_LOW,
161 SLEEP_DURATION_HI);
162 rc = __i2c_transfer(tpm_dev.client->adapter,
163 &msg2, 1);
164 if (rc > 0) {
165 /* Since len is unsigned, make doubly
166 * sure we do not underflow it.
167 */
168 if (msglen > len)
169 len = 0;
170 else
171 len -= msglen;
172 msg2.buf += msglen;
173 break;
174 }
175 /* If the I2C adapter rejected the request (e.g
176 * when the quirk read_max_len < len) fall back
177 * to a sane minimum value and try again.
178 */
179 if (rc == -EOPNOTSUPP)
180 tpm_dev.adapterlimit =
181 I2C_SMBUS_BLOCK_MAX;
182 }
183
184 if (rc <= 0)
185 goto out;
186 }
187 }
188
189out:
190 i2c_unlock_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT);
191 /* take care of 'guard time' */
192 usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
193
194 /* __i2c_transfer returns the number of successfully transferred
195 * messages.
196 * So rc should be greater than 0 here otherwise we have an error.
197 */
198 if (rc <= 0)
199 return -EIO;
200
201 return 0;
202}
203
204static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len,
205 unsigned int sleep_low,
206 unsigned int sleep_hi, u8 max_count)
207{
208 int rc = -EIO;
209 int count;
210
211 struct i2c_msg msg1 = {
212 .addr = tpm_dev.client->addr,
213 .len = len + 1,
214 .buf = tpm_dev.buf
215 };
216
217 if (len > TPM_I2C_INFINEON_BUFSIZE)
218 return -EINVAL;
219
220 if (!tpm_dev.client->adapter->algo->master_xfer)
221 return -EOPNOTSUPP;
222 i2c_lock_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT);
223
224 /* prepend the 'register address' to the buffer */
225 tpm_dev.buf[0] = addr;
226 memcpy(&(tpm_dev.buf[1]), buffer, len);
227
228 /*
229 * NOTE: We have to use these special mechanisms here and unfortunately
230 * cannot rely on the standard behavior of i2c_transfer.
231 * Even for newer chips the smbus functions are not
232 * suitable due to the 32 byte limit of the smbus.
233 */
234 for (count = 0; count < max_count; count++) {
235 rc = __i2c_transfer(tpm_dev.client->adapter, &msg1, 1);
236 if (rc > 0)
237 break;
238 usleep_range(sleep_low, sleep_hi);
239 }
240
241 i2c_unlock_bus(tpm_dev.client->adapter, I2C_LOCK_SEGMENT);
242 /* take care of 'guard time' */
243 usleep_range(SLEEP_DURATION_LOW, SLEEP_DURATION_HI);
244
245 /* __i2c_transfer returns the number of successfully transferred
246 * messages.
247 * So rc should be greater than 0 here otherwise we have an error.
248 */
249 if (rc <= 0)
250 return -EIO;
251
252 return 0;
253}
254
255/*
256 * iic_tpm_write() - write to TPM register
257 * @addr: register address to write to
258 * @buffer: containing data to be written
259 * @len: number of bytes to write
260 *
261 * Write len bytes from provided buffer to TPM register (little
262 * endian format, i.e. buffer[0] is written as first byte).
263 *
264 * NOTE: TPM is big-endian for multi-byte values. Multi-byte
265 * values have to be swapped.
266 *
267 * NOTE: use this function instead of the iic_tpm_write_generic function.
268 *
269 * Return -EIO on error, 0 on success
270 */
271static int iic_tpm_write(u8 addr, u8 *buffer, size_t len)
272{
273 return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LOW,
274 SLEEP_DURATION_HI, MAX_COUNT);
275}
276
277/*
278 * This function is needed especially for the cleanup situation after
279 * sending TPM_READY
280 * */
281static int iic_tpm_write_long(u8 addr, u8 *buffer, size_t len)
282{
283 return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LONG_LOW,
284 SLEEP_DURATION_LONG_HI, MAX_COUNT_LONG);
285}
286
287enum tis_access {
288 TPM_ACCESS_VALID = 0x80,
289 TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
290 TPM_ACCESS_REQUEST_PENDING = 0x04,
291 TPM_ACCESS_REQUEST_USE = 0x02,
292};
293
294enum tis_status {
295 TPM_STS_VALID = 0x80,
296 TPM_STS_COMMAND_READY = 0x40,
297 TPM_STS_GO = 0x20,
298 TPM_STS_DATA_AVAIL = 0x10,
299 TPM_STS_DATA_EXPECT = 0x08,
300};
301
302enum tis_defaults {
303 TIS_SHORT_TIMEOUT = 750, /* ms */
304 TIS_LONG_TIMEOUT = 2000, /* 2 sec */
305};
306
307#define TPM_ACCESS(l) (0x0000 | ((l) << 4))
308#define TPM_STS(l) (0x0001 | ((l) << 4))
309#define TPM_DATA_FIFO(l) (0x0005 | ((l) << 4))
310#define TPM_DID_VID(l) (0x0006 | ((l) << 4))
311
312static bool check_locality(struct tpm_chip *chip, int loc)
313{
314 u8 buf;
315 int rc;
316
317 rc = iic_tpm_read(TPM_ACCESS(loc), &buf, 1);
318 if (rc < 0)
319 return false;
320
321 if ((buf & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
322 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
323 tpm_dev.locality = loc;
324 return true;
325 }
326
327 return false;
328}
329
330/* implementation similar to tpm_tis */
331static void release_locality(struct tpm_chip *chip, int loc, int force)
332{
333 u8 buf;
334 if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0)
335 return;
336
337 if (force || (buf & (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
338 (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) {
339 buf = TPM_ACCESS_ACTIVE_LOCALITY;
340 iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
341 }
342}
343
344static int request_locality(struct tpm_chip *chip, int loc)
345{
346 unsigned long stop;
347 u8 buf = TPM_ACCESS_REQUEST_USE;
348
349 if (check_locality(chip, loc))
350 return loc;
351
352 iic_tpm_write(TPM_ACCESS(loc), &buf, 1);
353
354 /* wait for burstcount */
355 stop = jiffies + chip->timeout_a;
356 do {
357 if (check_locality(chip, loc))
358 return loc;
359 usleep_range(TPM_TIMEOUT_US_LOW, TPM_TIMEOUT_US_HI);
360 } while (time_before(jiffies, stop));
361
362 return -ETIME;
363}
364
365static u8 tpm_tis_i2c_status(struct tpm_chip *chip)
366{
367 /* NOTE: since I2C read may fail, return 0 in this case --> time-out */
368 u8 buf = 0xFF;
369 u8 i = 0;
370
371 do {
372 if (iic_tpm_read(TPM_STS(tpm_dev.locality), &buf, 1) < 0)
373 return 0;
374
375 i++;
376 /* if locallity is set STS should not be 0xFF */
377 } while ((buf == 0xFF) && i < 10);
378
379 return buf;
380}
381
382static void tpm_tis_i2c_ready(struct tpm_chip *chip)
383{
384 /* this causes the current command to be aborted */
385 u8 buf = TPM_STS_COMMAND_READY;
386 iic_tpm_write_long(TPM_STS(tpm_dev.locality), &buf, 1);
387}
388
389static ssize_t get_burstcount(struct tpm_chip *chip)
390{
391 unsigned long stop;
392 ssize_t burstcnt;
393 u8 buf[3];
394
395 /* wait for burstcount */
396 /* which timeout value, spec has 2 answers (c & d) */
397 stop = jiffies + chip->timeout_d;
398 do {
399 /* Note: STS is little endian */
400 if (iic_tpm_read(TPM_STS(tpm_dev.locality)+1, buf, 3) < 0)
401 burstcnt = 0;
402 else
403 burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0];
404
405 if (burstcnt)
406 return burstcnt;
407
408 usleep_range(TPM_TIMEOUT_US_LOW, TPM_TIMEOUT_US_HI);
409 } while (time_before(jiffies, stop));
410 return -EBUSY;
411}
412
413static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
414 int *status)
415{
416 unsigned long stop;
417
418 /* check current status */
419 *status = tpm_tis_i2c_status(chip);
420 if ((*status != 0xFF) && (*status & mask) == mask)
421 return 0;
422
423 stop = jiffies + timeout;
424 do {
425 /* since we just checked the status, give the TPM some time */
426 usleep_range(TPM_TIMEOUT_US_LOW, TPM_TIMEOUT_US_HI);
427 *status = tpm_tis_i2c_status(chip);
428 if ((*status & mask) == mask)
429 return 0;
430
431 } while (time_before(jiffies, stop));
432
433 return -ETIME;
434}
435
436static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
437{
438 size_t size = 0;
439 ssize_t burstcnt;
440 u8 retries = 0;
441 int rc;
442
443 while (size < count) {
444 burstcnt = get_burstcount(chip);
445
446 /* burstcnt < 0 = TPM is busy */
447 if (burstcnt < 0)
448 return burstcnt;
449
450 /* limit received data to max. left */
451 if (burstcnt > (count - size))
452 burstcnt = count - size;
453
454 rc = iic_tpm_read(TPM_DATA_FIFO(tpm_dev.locality),
455 &(buf[size]), burstcnt);
456 if (rc == 0)
457 size += burstcnt;
458 else if (rc < 0)
459 retries++;
460
461 /* avoid endless loop in case of broken HW */
462 if (retries > MAX_COUNT_LONG)
463 return -EIO;
464 }
465 return size;
466}
467
468static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count)
469{
470 int size = 0;
471 int status;
472 u32 expected;
473
474 if (count < TPM_HEADER_SIZE) {
475 size = -EIO;
476 goto out;
477 }
478
479 /* read first 10 bytes, including tag, paramsize, and result */
480 size = recv_data(chip, buf, TPM_HEADER_SIZE);
481 if (size < TPM_HEADER_SIZE) {
482 dev_err(&chip->dev, "Unable to read header\n");
483 goto out;
484 }
485
486 expected = be32_to_cpu(*(__be32 *)(buf + 2));
487 if (((size_t) expected > count) || (expected < TPM_HEADER_SIZE)) {
488 size = -EIO;
489 goto out;
490 }
491
492 size += recv_data(chip, &buf[TPM_HEADER_SIZE],
493 expected - TPM_HEADER_SIZE);
494 if (size < expected) {
495 dev_err(&chip->dev, "Unable to read remainder of result\n");
496 size = -ETIME;
497 goto out;
498 }
499
500 wait_for_stat(chip, TPM_STS_VALID, chip->timeout_c, &status);
501 if (status & TPM_STS_DATA_AVAIL) { /* retry? */
502 dev_err(&chip->dev, "Error left over data\n");
503 size = -EIO;
504 goto out;
505 }
506
507out:
508 tpm_tis_i2c_ready(chip);
509 /* The TPM needs some time to clean up here,
510 * so we sleep rather than keeping the bus busy
511 */
512 usleep_range(SLEEP_DURATION_RESET_LOW, SLEEP_DURATION_RESET_HI);
513 release_locality(chip, tpm_dev.locality, 0);
514 return size;
515}
516
517static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len)
518{
519 int rc, status;
520 ssize_t burstcnt;
521 size_t count = 0;
522 u8 retries = 0;
523 u8 sts = TPM_STS_GO;
524
525 if (len > TPM_I2C_INFINEON_BUFSIZE)
526 return -E2BIG;
527
528 if (request_locality(chip, 0) < 0)
529 return -EBUSY;
530
531 status = tpm_tis_i2c_status(chip);
532 if ((status & TPM_STS_COMMAND_READY) == 0) {
533 tpm_tis_i2c_ready(chip);
534 if (wait_for_stat
535 (chip, TPM_STS_COMMAND_READY,
536 chip->timeout_b, &status) < 0) {
537 rc = -ETIME;
538 goto out_err;
539 }
540 }
541
542 while (count < len - 1) {
543 burstcnt = get_burstcount(chip);
544
545 /* burstcnt < 0 = TPM is busy */
546 if (burstcnt < 0)
547 return burstcnt;
548
549 if (burstcnt > (len - 1 - count))
550 burstcnt = len - 1 - count;
551
552 rc = iic_tpm_write(TPM_DATA_FIFO(tpm_dev.locality),
553 &(buf[count]), burstcnt);
554 if (rc == 0)
555 count += burstcnt;
556 else if (rc < 0)
557 retries++;
558
559 /* avoid endless loop in case of broken HW */
560 if (retries > MAX_COUNT_LONG) {
561 rc = -EIO;
562 goto out_err;
563 }
564
565 wait_for_stat(chip, TPM_STS_VALID,
566 chip->timeout_c, &status);
567
568 if ((status & TPM_STS_DATA_EXPECT) == 0) {
569 rc = -EIO;
570 goto out_err;
571 }
572 }
573
574 /* write last byte */
575 iic_tpm_write(TPM_DATA_FIFO(tpm_dev.locality), &(buf[count]), 1);
576 wait_for_stat(chip, TPM_STS_VALID, chip->timeout_c, &status);
577 if ((status & TPM_STS_DATA_EXPECT) != 0) {
578 rc = -EIO;
579 goto out_err;
580 }
581
582 /* go and do it */
583 iic_tpm_write(TPM_STS(tpm_dev.locality), &sts, 1);
584
585 return 0;
586out_err:
587 tpm_tis_i2c_ready(chip);
588 /* The TPM needs some time to clean up here,
589 * so we sleep rather than keeping the bus busy
590 */
591 usleep_range(SLEEP_DURATION_RESET_LOW, SLEEP_DURATION_RESET_HI);
592 release_locality(chip, tpm_dev.locality, 0);
593 return rc;
594}
595
596static bool tpm_tis_i2c_req_canceled(struct tpm_chip *chip, u8 status)
597{
598 return (status == TPM_STS_COMMAND_READY);
599}
600
601static const struct tpm_class_ops tpm_tis_i2c = {
602 .flags = TPM_OPS_AUTO_STARTUP,
603 .status = tpm_tis_i2c_status,
604 .recv = tpm_tis_i2c_recv,
605 .send = tpm_tis_i2c_send,
606 .cancel = tpm_tis_i2c_ready,
607 .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
608 .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
609 .req_canceled = tpm_tis_i2c_req_canceled,
610};
611
612static int tpm_tis_i2c_init(struct device *dev)
613{
614 u32 vendor;
615 int rc = 0;
616 struct tpm_chip *chip;
617
618 chip = tpmm_chip_alloc(dev, &tpm_tis_i2c);
619 if (IS_ERR(chip))
620 return PTR_ERR(chip);
621
622 /* Default timeouts */
623 chip->timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
624 chip->timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
625 chip->timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
626 chip->timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
627
628 if (request_locality(chip, 0) != 0) {
629 dev_err(dev, "could not request locality\n");
630 rc = -ENODEV;
631 goto out_err;
632 }
633
634 /* read four bytes from DID_VID register */
635 if (iic_tpm_read(TPM_DID_VID(0), (u8 *)&vendor, 4) < 0) {
636 dev_err(dev, "could not read vendor id\n");
637 rc = -EIO;
638 goto out_release;
639 }
640
641 if (vendor == TPM_TIS_I2C_DID_VID_9645) {
642 tpm_dev.chip_type = SLB9645;
643 } else if (vendor == TPM_TIS_I2C_DID_VID_9635) {
644 tpm_dev.chip_type = SLB9635;
645 } else {
646 dev_err(dev, "vendor id did not match! ID was %08x\n", vendor);
647 rc = -ENODEV;
648 goto out_release;
649 }
650
651 dev_info(dev, "1.2 TPM (device-id 0x%X)\n", vendor >> 16);
652
653 tpm_dev.chip = chip;
654
655 return tpm_chip_register(chip);
656out_release:
657 release_locality(chip, tpm_dev.locality, 1);
658 tpm_dev.client = NULL;
659out_err:
660 return rc;
661}
662
663static const struct i2c_device_id tpm_tis_i2c_table[] = {
664 {"tpm_i2c_infineon"},
665 {"slb9635tt"},
666 {"slb9645tt"},
667 {},
668};
669
670MODULE_DEVICE_TABLE(i2c, tpm_tis_i2c_table);
671
672#ifdef CONFIG_OF
673static const struct of_device_id tpm_tis_i2c_of_match[] = {
674 {.compatible = "infineon,tpm_i2c_infineon"},
675 {.compatible = "infineon,slb9635tt"},
676 {.compatible = "infineon,slb9645tt"},
677 {},
678};
679MODULE_DEVICE_TABLE(of, tpm_tis_i2c_of_match);
680#endif
681
682static SIMPLE_DEV_PM_OPS(tpm_tis_i2c_ops, tpm_pm_suspend, tpm_pm_resume);
683
684static int tpm_tis_i2c_probe(struct i2c_client *client)
685{
686 int rc;
687 struct device *dev = &(client->dev);
688
689 if (tpm_dev.client != NULL) {
690 dev_err(dev, "This driver only supports one client at a time\n");
691 return -EBUSY; /* We only support one client */
692 }
693
694 if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
695 dev_err(dev, "no algorithms associated to the i2c bus\n");
696 return -ENODEV;
697 }
698
699 tpm_dev.client = client;
700 rc = tpm_tis_i2c_init(&client->dev);
701 if (rc != 0) {
702 tpm_dev.client = NULL;
703 rc = -ENODEV;
704 }
705 return rc;
706}
707
708static void tpm_tis_i2c_remove(struct i2c_client *client)
709{
710 struct tpm_chip *chip = tpm_dev.chip;
711
712 tpm_chip_unregister(chip);
713 release_locality(chip, tpm_dev.locality, 1);
714 tpm_dev.client = NULL;
715}
716
717static struct i2c_driver tpm_tis_i2c_driver = {
718 .id_table = tpm_tis_i2c_table,
719 .probe = tpm_tis_i2c_probe,
720 .remove = tpm_tis_i2c_remove,
721 .driver = {
722 .name = "tpm_i2c_infineon",
723 .pm = &tpm_tis_i2c_ops,
724 .of_match_table = of_match_ptr(tpm_tis_i2c_of_match),
725 },
726};
727
728module_i2c_driver(tpm_tis_i2c_driver);
729MODULE_AUTHOR("Peter Huewe <peter.huewe@infineon.com>");
730MODULE_DESCRIPTION("TPM TIS I2C Infineon Driver");
731MODULE_VERSION("2.2.0");
732MODULE_LICENSE("GPL");