1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /******************************************************************************
3 * Nuvoton TPM I2C Device Driver Interface for WPCT301/NPCT501/NPCT6XX,
4 * based on the TCG TPM Interface Spec version 1.2.
5 * Specifications at www.trustedcomputinggroup.org
6 *
7 * Copyright (C) 2011, Nuvoton Technology Corporation.
8 * Dan Morav <dan.morav@nuvoton.com>
9 * Copyright (C) 2013, Obsidian Research Corp.
10 * Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
11 *
12 * Nuvoton contact information: APC.Support@nuvoton.com
13 *****************************************************************************/
14
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/moduleparam.h>
18 #include <linux/slab.h>
19 #include <linux/interrupt.h>
20 #include <linux/wait.h>
21 #include <linux/i2c.h>
22 #include <linux/of.h>
23 #include <linux/property.h>
24 #include "tpm.h"
25
26 /* I2C interface offsets */
27 #define TPM_STS 0x00
28 #define TPM_BURST_COUNT 0x01
29 #define TPM_DATA_FIFO_W 0x20
30 #define TPM_DATA_FIFO_R 0x40
31 #define TPM_VID_DID_RID 0x60
32 #define TPM_I2C_RETRIES 5
33 /*
34 * I2C bus device maximum buffer size w/o counting I2C address or command
35 * i.e. max size required for I2C write is 34 = addr, command, 32 bytes data
36 */
37 #define TPM_I2C_MAX_BUF_SIZE 32
38 #define TPM_I2C_RETRY_COUNT 32
39 #define TPM_I2C_BUS_DELAY 1000 /* usec */
40 #define TPM_I2C_RETRY_DELAY_SHORT (2 * 1000) /* usec */
41 #define TPM_I2C_RETRY_DELAY_LONG (10 * 1000) /* usec */
42 #define TPM_I2C_DELAY_RANGE 300 /* usec */
43
44 #define OF_IS_TPM2 ((void *)1)
45 #define I2C_IS_TPM2 1
46
47 struct priv_data {
48 int irq;
49 unsigned int intrs;
50 wait_queue_head_t read_queue;
51 };
52
i2c_nuvoton_read_buf(struct i2c_client * client,u8 offset,u8 size,u8 * data)53 static s32 i2c_nuvoton_read_buf(struct i2c_client *client, u8 offset, u8 size,
54 u8 *data)
55 {
56 s32 status;
57
58 status = i2c_smbus_read_i2c_block_data(client, offset, size, data);
59 dev_dbg(&client->dev,
60 "%s(offset=%u size=%u data=%*ph) -> sts=%d\n", __func__,
61 offset, size, (int)size, data, status);
62 return status;
63 }
64
i2c_nuvoton_write_buf(struct i2c_client * client,u8 offset,u8 size,u8 * data)65 static s32 i2c_nuvoton_write_buf(struct i2c_client *client, u8 offset, u8 size,
66 u8 *data)
67 {
68 s32 status;
69
70 status = i2c_smbus_write_i2c_block_data(client, offset, size, data);
71 dev_dbg(&client->dev,
72 "%s(offset=%u size=%u data=%*ph) -> sts=%d\n", __func__,
73 offset, size, (int)size, data, status);
74 return status;
75 }
76
77 #define TPM_STS_VALID 0x80
78 #define TPM_STS_COMMAND_READY 0x40
79 #define TPM_STS_GO 0x20
80 #define TPM_STS_DATA_AVAIL 0x10
81 #define TPM_STS_EXPECT 0x08
82 #define TPM_STS_RESPONSE_RETRY 0x02
83 #define TPM_STS_ERR_VAL 0x07 /* bit2...bit0 reads always 0 */
84
85 #define TPM_I2C_SHORT_TIMEOUT 750 /* ms */
86 #define TPM_I2C_LONG_TIMEOUT 2000 /* 2 sec */
87
88 /* read TPM_STS register */
i2c_nuvoton_read_status(struct tpm_chip * chip)89 static u8 i2c_nuvoton_read_status(struct tpm_chip *chip)
90 {
91 struct i2c_client *client = to_i2c_client(chip->dev.parent);
92 s32 status;
93 u8 data;
94
95 status = i2c_nuvoton_read_buf(client, TPM_STS, 1, &data);
96 if (status <= 0) {
97 dev_err(&chip->dev, "%s() error return %d\n", __func__,
98 status);
99 data = TPM_STS_ERR_VAL;
100 }
101
102 return data;
103 }
104
105 /* write byte to TPM_STS register */
i2c_nuvoton_write_status(struct i2c_client * client,u8 data)106 static s32 i2c_nuvoton_write_status(struct i2c_client *client, u8 data)
107 {
108 s32 status;
109 int i;
110
111 /* this causes the current command to be aborted */
112 for (i = 0, status = -1; i < TPM_I2C_RETRY_COUNT && status < 0; i++) {
113 status = i2c_nuvoton_write_buf(client, TPM_STS, 1, &data);
114 if (status < 0)
115 usleep_range(TPM_I2C_BUS_DELAY, TPM_I2C_BUS_DELAY
116 + TPM_I2C_DELAY_RANGE);
117 }
118 return status;
119 }
120
121 /* write commandReady to TPM_STS register */
i2c_nuvoton_ready(struct tpm_chip * chip)122 static void i2c_nuvoton_ready(struct tpm_chip *chip)
123 {
124 struct i2c_client *client = to_i2c_client(chip->dev.parent);
125 s32 status;
126
127 /* this causes the current command to be aborted */
128 status = i2c_nuvoton_write_status(client, TPM_STS_COMMAND_READY);
129 if (status < 0)
130 dev_err(&chip->dev,
131 "%s() fail to write TPM_STS.commandReady\n", __func__);
132 }
133
134 /* read burstCount field from TPM_STS register
135 * return -1 on fail to read */
i2c_nuvoton_get_burstcount(struct i2c_client * client,struct tpm_chip * chip)136 static int i2c_nuvoton_get_burstcount(struct i2c_client *client,
137 struct tpm_chip *chip)
138 {
139 unsigned long stop = jiffies + chip->timeout_d;
140 s32 status;
141 int burst_count = -1;
142 u8 data;
143
144 /* wait for burstcount to be non-zero */
145 do {
146 /* in I2C burstCount is 1 byte */
147 status = i2c_nuvoton_read_buf(client, TPM_BURST_COUNT, 1,
148 &data);
149 if (status > 0 && data > 0) {
150 burst_count = min_t(u8, TPM_I2C_MAX_BUF_SIZE, data);
151 break;
152 }
153 usleep_range(TPM_I2C_BUS_DELAY, TPM_I2C_BUS_DELAY
154 + TPM_I2C_DELAY_RANGE);
155 } while (time_before(jiffies, stop));
156
157 return burst_count;
158 }
159
160 /*
161 * WPCT301/NPCT501/NPCT6XX SINT# supports only dataAvail
162 * any call to this function which is not waiting for dataAvail will
163 * set queue to NULL to avoid waiting for interrupt
164 */
i2c_nuvoton_check_status(struct tpm_chip * chip,u8 mask,u8 value)165 static bool i2c_nuvoton_check_status(struct tpm_chip *chip, u8 mask, u8 value)
166 {
167 u8 status = i2c_nuvoton_read_status(chip);
168 return (status != TPM_STS_ERR_VAL) && ((status & mask) == value);
169 }
170
i2c_nuvoton_wait_for_stat(struct tpm_chip * chip,u8 mask,u8 value,u32 timeout,wait_queue_head_t * queue)171 static int i2c_nuvoton_wait_for_stat(struct tpm_chip *chip, u8 mask, u8 value,
172 u32 timeout, wait_queue_head_t *queue)
173 {
174 if ((chip->flags & TPM_CHIP_FLAG_IRQ) && queue) {
175 s32 rc;
176 struct priv_data *priv = dev_get_drvdata(&chip->dev);
177 unsigned int cur_intrs = priv->intrs;
178
179 enable_irq(priv->irq);
180 rc = wait_event_interruptible_timeout(*queue,
181 cur_intrs != priv->intrs,
182 timeout);
183 if (rc > 0)
184 return 0;
185 /* At this point we know that the SINT pin is asserted, so we
186 * do not need to do i2c_nuvoton_check_status */
187 } else {
188 unsigned long ten_msec, stop;
189 bool status_valid;
190
191 /* check current status */
192 status_valid = i2c_nuvoton_check_status(chip, mask, value);
193 if (status_valid)
194 return 0;
195
196 /* use polling to wait for the event */
197 ten_msec = jiffies + usecs_to_jiffies(TPM_I2C_RETRY_DELAY_LONG);
198 stop = jiffies + timeout;
199 do {
200 if (time_before(jiffies, ten_msec))
201 usleep_range(TPM_I2C_RETRY_DELAY_SHORT,
202 TPM_I2C_RETRY_DELAY_SHORT
203 + TPM_I2C_DELAY_RANGE);
204 else
205 usleep_range(TPM_I2C_RETRY_DELAY_LONG,
206 TPM_I2C_RETRY_DELAY_LONG
207 + TPM_I2C_DELAY_RANGE);
208 status_valid = i2c_nuvoton_check_status(chip, mask,
209 value);
210 if (status_valid)
211 return 0;
212 } while (time_before(jiffies, stop));
213 }
214 dev_err(&chip->dev, "%s(%02x, %02x) -> timeout\n", __func__, mask,
215 value);
216 return -ETIMEDOUT;
217 }
218
219 /* wait for dataAvail field to be set in the TPM_STS register */
i2c_nuvoton_wait_for_data_avail(struct tpm_chip * chip,u32 timeout,wait_queue_head_t * queue)220 static int i2c_nuvoton_wait_for_data_avail(struct tpm_chip *chip, u32 timeout,
221 wait_queue_head_t *queue)
222 {
223 return i2c_nuvoton_wait_for_stat(chip,
224 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
225 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
226 timeout, queue);
227 }
228
229 /* Read @count bytes into @buf from TPM_RD_FIFO register */
i2c_nuvoton_recv_data(struct i2c_client * client,struct tpm_chip * chip,u8 * buf,size_t count)230 static int i2c_nuvoton_recv_data(struct i2c_client *client,
231 struct tpm_chip *chip, u8 *buf, size_t count)
232 {
233 struct priv_data *priv = dev_get_drvdata(&chip->dev);
234 s32 rc;
235 int burst_count, bytes2read, size = 0;
236
237 while (size < count &&
238 i2c_nuvoton_wait_for_data_avail(chip,
239 chip->timeout_c,
240 &priv->read_queue) == 0) {
241 burst_count = i2c_nuvoton_get_burstcount(client, chip);
242 if (burst_count < 0) {
243 dev_err(&chip->dev,
244 "%s() fail to read burstCount=%d\n", __func__,
245 burst_count);
246 return -EIO;
247 }
248 bytes2read = min_t(size_t, burst_count, count - size);
249 rc = i2c_nuvoton_read_buf(client, TPM_DATA_FIFO_R,
250 bytes2read, &buf[size]);
251 if (rc < 0) {
252 dev_err(&chip->dev,
253 "%s() fail on i2c_nuvoton_read_buf()=%d\n",
254 __func__, rc);
255 return -EIO;
256 }
257 dev_dbg(&chip->dev, "%s(%d):", __func__, bytes2read);
258 size += bytes2read;
259 }
260
261 return size;
262 }
263
264 /* Read TPM command results */
i2c_nuvoton_recv(struct tpm_chip * chip,u8 * buf,size_t count)265 static int i2c_nuvoton_recv(struct tpm_chip *chip, u8 *buf, size_t count)
266 {
267 struct priv_data *priv = dev_get_drvdata(&chip->dev);
268 struct device *dev = chip->dev.parent;
269 struct i2c_client *client = to_i2c_client(dev);
270 s32 rc;
271 int status;
272 int burst_count;
273 int retries;
274 int size = 0;
275 u32 expected;
276
277 if (count < TPM_HEADER_SIZE) {
278 i2c_nuvoton_ready(chip); /* return to idle */
279 dev_err(dev, "%s() count < header size\n", __func__);
280 return -EIO;
281 }
282 for (retries = 0; retries < TPM_I2C_RETRIES; retries++) {
283 if (retries > 0) {
284 /* if this is not the first trial, set responseRetry */
285 i2c_nuvoton_write_status(client,
286 TPM_STS_RESPONSE_RETRY);
287 }
288 /*
289 * read first available (> 10 bytes), including:
290 * tag, paramsize, and result
291 */
292 status = i2c_nuvoton_wait_for_data_avail(
293 chip, chip->timeout_c, &priv->read_queue);
294 if (status != 0) {
295 dev_err(dev, "%s() timeout on dataAvail\n", __func__);
296 size = -ETIMEDOUT;
297 continue;
298 }
299 burst_count = i2c_nuvoton_get_burstcount(client, chip);
300 if (burst_count < 0) {
301 dev_err(dev, "%s() fail to get burstCount\n", __func__);
302 size = -EIO;
303 continue;
304 }
305 size = i2c_nuvoton_recv_data(client, chip, buf,
306 burst_count);
307 if (size < TPM_HEADER_SIZE) {
308 dev_err(dev, "%s() fail to read header\n", __func__);
309 size = -EIO;
310 continue;
311 }
312 /*
313 * convert number of expected bytes field from big endian 32 bit
314 * to machine native
315 */
316 expected = be32_to_cpu(*(__be32 *) (buf + 2));
317 if (expected > count || expected < size) {
318 dev_err(dev, "%s() expected > count\n", __func__);
319 size = -EIO;
320 continue;
321 }
322 rc = i2c_nuvoton_recv_data(client, chip, &buf[size],
323 expected - size);
324 size += rc;
325 if (rc < 0 || size < expected) {
326 dev_err(dev, "%s() fail to read remainder of result\n",
327 __func__);
328 size = -EIO;
329 continue;
330 }
331 if (i2c_nuvoton_wait_for_stat(
332 chip, TPM_STS_VALID | TPM_STS_DATA_AVAIL,
333 TPM_STS_VALID, chip->timeout_c,
334 NULL)) {
335 dev_err(dev, "%s() error left over data\n", __func__);
336 size = -ETIMEDOUT;
337 continue;
338 }
339 break;
340 }
341 i2c_nuvoton_ready(chip);
342 dev_dbg(&chip->dev, "%s() -> %d\n", __func__, size);
343 return size;
344 }
345
346 /*
347 * Send TPM command.
348 *
349 * If interrupts are used (signaled by an irq set in the vendor structure)
350 * tpm.c can skip polling for the data to be available as the interrupt is
351 * waited for here
352 */
i2c_nuvoton_send(struct tpm_chip * chip,u8 * buf,size_t len)353 static int i2c_nuvoton_send(struct tpm_chip *chip, u8 *buf, size_t len)
354 {
355 struct priv_data *priv = dev_get_drvdata(&chip->dev);
356 struct device *dev = chip->dev.parent;
357 struct i2c_client *client = to_i2c_client(dev);
358 u32 ordinal;
359 unsigned long duration;
360 size_t count = 0;
361 int burst_count, bytes2write, retries, rc = -EIO;
362
363 for (retries = 0; retries < TPM_RETRY; retries++) {
364 i2c_nuvoton_ready(chip);
365 if (i2c_nuvoton_wait_for_stat(chip, TPM_STS_COMMAND_READY,
366 TPM_STS_COMMAND_READY,
367 chip->timeout_b, NULL)) {
368 dev_err(dev, "%s() timeout on commandReady\n",
369 __func__);
370 rc = -EIO;
371 continue;
372 }
373 rc = 0;
374 while (count < len - 1) {
375 burst_count = i2c_nuvoton_get_burstcount(client,
376 chip);
377 if (burst_count < 0) {
378 dev_err(dev, "%s() fail get burstCount\n",
379 __func__);
380 rc = -EIO;
381 break;
382 }
383 bytes2write = min_t(size_t, burst_count,
384 len - 1 - count);
385 rc = i2c_nuvoton_write_buf(client, TPM_DATA_FIFO_W,
386 bytes2write, &buf[count]);
387 if (rc < 0) {
388 dev_err(dev, "%s() fail i2cWriteBuf\n",
389 __func__);
390 break;
391 }
392 dev_dbg(dev, "%s(%d):", __func__, bytes2write);
393 count += bytes2write;
394 rc = i2c_nuvoton_wait_for_stat(chip,
395 TPM_STS_VALID |
396 TPM_STS_EXPECT,
397 TPM_STS_VALID |
398 TPM_STS_EXPECT,
399 chip->timeout_c,
400 NULL);
401 if (rc < 0) {
402 dev_err(dev, "%s() timeout on Expect\n",
403 __func__);
404 rc = -ETIMEDOUT;
405 break;
406 }
407 }
408 if (rc < 0)
409 continue;
410
411 /* write last byte */
412 rc = i2c_nuvoton_write_buf(client, TPM_DATA_FIFO_W, 1,
413 &buf[count]);
414 if (rc < 0) {
415 dev_err(dev, "%s() fail to write last byte\n",
416 __func__);
417 rc = -EIO;
418 continue;
419 }
420 dev_dbg(dev, "%s(last): %02x", __func__, buf[count]);
421 rc = i2c_nuvoton_wait_for_stat(chip,
422 TPM_STS_VALID | TPM_STS_EXPECT,
423 TPM_STS_VALID,
424 chip->timeout_c, NULL);
425 if (rc) {
426 dev_err(dev, "%s() timeout on Expect to clear\n",
427 __func__);
428 rc = -ETIMEDOUT;
429 continue;
430 }
431 break;
432 }
433 if (rc < 0) {
434 /* retries == TPM_RETRY */
435 i2c_nuvoton_ready(chip);
436 return rc;
437 }
438 /* execute the TPM command */
439 rc = i2c_nuvoton_write_status(client, TPM_STS_GO);
440 if (rc < 0) {
441 dev_err(dev, "%s() fail to write Go\n", __func__);
442 i2c_nuvoton_ready(chip);
443 return rc;
444 }
445 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
446 duration = tpm_calc_ordinal_duration(chip, ordinal);
447
448 rc = i2c_nuvoton_wait_for_data_avail(chip, duration, &priv->read_queue);
449 if (rc) {
450 dev_err(dev, "%s() timeout command duration %ld\n",
451 __func__, duration);
452 i2c_nuvoton_ready(chip);
453 return rc;
454 }
455
456 dev_dbg(dev, "%s() -> %zd\n", __func__, len);
457 return 0;
458 }
459
i2c_nuvoton_req_canceled(struct tpm_chip * chip,u8 status)460 static bool i2c_nuvoton_req_canceled(struct tpm_chip *chip, u8 status)
461 {
462 return (status == TPM_STS_COMMAND_READY);
463 }
464
465 static const struct tpm_class_ops tpm_i2c = {
466 .flags = TPM_OPS_AUTO_STARTUP,
467 .status = i2c_nuvoton_read_status,
468 .recv = i2c_nuvoton_recv,
469 .send = i2c_nuvoton_send,
470 .cancel = i2c_nuvoton_ready,
471 .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
472 .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
473 .req_canceled = i2c_nuvoton_req_canceled,
474 };
475
476 /* The only purpose for the handler is to signal to any waiting threads that
477 * the interrupt is currently being asserted. The driver does not do any
478 * processing triggered by interrupts, and the chip provides no way to mask at
479 * the source (plus that would be slow over I2C). Run the IRQ as a one-shot,
480 * this means it cannot be shared. */
i2c_nuvoton_int_handler(int dummy,void * dev_id)481 static irqreturn_t i2c_nuvoton_int_handler(int dummy, void *dev_id)
482 {
483 struct tpm_chip *chip = dev_id;
484 struct priv_data *priv = dev_get_drvdata(&chip->dev);
485
486 priv->intrs++;
487 wake_up(&priv->read_queue);
488 disable_irq_nosync(priv->irq);
489 return IRQ_HANDLED;
490 }
491
get_vid(struct i2c_client * client,u32 * res)492 static int get_vid(struct i2c_client *client, u32 *res)
493 {
494 static const u8 vid_did_rid_value[] = { 0x50, 0x10, 0xfe };
495 u32 temp;
496 s32 rc;
497
498 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
499 return -ENODEV;
500 rc = i2c_nuvoton_read_buf(client, TPM_VID_DID_RID, 4, (u8 *)&temp);
501 if (rc < 0)
502 return rc;
503
504 /* check WPCT301 values - ignore RID */
505 if (memcmp(&temp, vid_did_rid_value, sizeof(vid_did_rid_value))) {
506 /*
507 * f/w rev 2.81 has an issue where the VID_DID_RID is not
508 * reporting the right value. so give it another chance at
509 * offset 0x20 (FIFO_W).
510 */
511 rc = i2c_nuvoton_read_buf(client, TPM_DATA_FIFO_W, 4,
512 (u8 *) (&temp));
513 if (rc < 0)
514 return rc;
515
516 /* check WPCT301 values - ignore RID */
517 if (memcmp(&temp, vid_did_rid_value,
518 sizeof(vid_did_rid_value)))
519 return -ENODEV;
520 }
521
522 *res = temp;
523 return 0;
524 }
525
i2c_nuvoton_probe(struct i2c_client * client)526 static int i2c_nuvoton_probe(struct i2c_client *client)
527 {
528 int rc;
529 struct tpm_chip *chip;
530 struct device *dev = &client->dev;
531 struct priv_data *priv;
532 u32 vid = 0;
533
534 rc = get_vid(client, &vid);
535 if (rc)
536 return rc;
537
538 dev_info(dev, "VID: %04X DID: %02X RID: %02X\n", (u16) vid,
539 (u8) (vid >> 16), (u8) (vid >> 24));
540
541 chip = tpmm_chip_alloc(dev, &tpm_i2c);
542 if (IS_ERR(chip))
543 return PTR_ERR(chip);
544
545 priv = devm_kzalloc(dev, sizeof(struct priv_data), GFP_KERNEL);
546 if (!priv)
547 return -ENOMEM;
548
549 if (i2c_get_match_data(client))
550 chip->flags |= TPM_CHIP_FLAG_TPM2;
551
552 init_waitqueue_head(&priv->read_queue);
553
554 /* Default timeouts */
555 chip->timeout_a = msecs_to_jiffies(TPM_I2C_SHORT_TIMEOUT);
556 chip->timeout_b = msecs_to_jiffies(TPM_I2C_LONG_TIMEOUT);
557 chip->timeout_c = msecs_to_jiffies(TPM_I2C_SHORT_TIMEOUT);
558 chip->timeout_d = msecs_to_jiffies(TPM_I2C_SHORT_TIMEOUT);
559
560 dev_set_drvdata(&chip->dev, priv);
561
562 /*
563 * I2C intfcaps (interrupt capabilitieis) in the chip are hard coded to:
564 * TPM_INTF_INT_LEVEL_LOW | TPM_INTF_DATA_AVAIL_INT
565 * The IRQ should be set in the i2c_board_info (which is done
566 * automatically in of_i2c_register_devices, for device tree users */
567 priv->irq = client->irq;
568 if (client->irq) {
569 dev_dbg(dev, "%s() priv->irq\n", __func__);
570 rc = devm_request_irq(dev, client->irq,
571 i2c_nuvoton_int_handler,
572 IRQF_TRIGGER_LOW,
573 dev_name(&chip->dev),
574 chip);
575 if (rc) {
576 dev_err(dev, "%s() Unable to request irq: %d for use\n",
577 __func__, priv->irq);
578 priv->irq = 0;
579 } else {
580 chip->flags |= TPM_CHIP_FLAG_IRQ;
581 /* Clear any pending interrupt */
582 i2c_nuvoton_ready(chip);
583 /* - wait for TPM_STS==0xA0 (stsValid, commandReady) */
584 rc = i2c_nuvoton_wait_for_stat(chip,
585 TPM_STS_COMMAND_READY,
586 TPM_STS_COMMAND_READY,
587 chip->timeout_b,
588 NULL);
589 if (rc == 0) {
590 /*
591 * TIS is in ready state
592 * write dummy byte to enter reception state
593 * TPM_DATA_FIFO_W <- rc (0)
594 */
595 rc = i2c_nuvoton_write_buf(client,
596 TPM_DATA_FIFO_W,
597 1, (u8 *) (&rc));
598 if (rc < 0)
599 return rc;
600 /* TPM_STS <- 0x40 (commandReady) */
601 i2c_nuvoton_ready(chip);
602 } else {
603 /*
604 * timeout_b reached - command was
605 * aborted. TIS should now be in idle state -
606 * only TPM_STS_VALID should be set
607 */
608 if (i2c_nuvoton_read_status(chip) !=
609 TPM_STS_VALID)
610 return -EIO;
611 }
612 }
613 }
614
615 return tpm_chip_register(chip);
616 }
617
i2c_nuvoton_remove(struct i2c_client * client)618 static void i2c_nuvoton_remove(struct i2c_client *client)
619 {
620 struct tpm_chip *chip = i2c_get_clientdata(client);
621
622 tpm_chip_unregister(chip);
623 }
624
625 static const struct i2c_device_id i2c_nuvoton_id[] = {
626 {"tpm_i2c_nuvoton"},
627 {"tpm2_i2c_nuvoton", .driver_data = I2C_IS_TPM2},
628 {}
629 };
630 MODULE_DEVICE_TABLE(i2c, i2c_nuvoton_id);
631
632 #ifdef CONFIG_OF
633 static const struct of_device_id i2c_nuvoton_of_match[] = {
634 {.compatible = "nuvoton,npct501"},
635 {.compatible = "winbond,wpct301"},
636 {.compatible = "nuvoton,npct601", .data = OF_IS_TPM2},
637 {},
638 };
639 MODULE_DEVICE_TABLE(of, i2c_nuvoton_of_match);
640 #endif
641
642 static SIMPLE_DEV_PM_OPS(i2c_nuvoton_pm_ops, tpm_pm_suspend, tpm_pm_resume);
643
644 static struct i2c_driver i2c_nuvoton_driver = {
645 .id_table = i2c_nuvoton_id,
646 .probe = i2c_nuvoton_probe,
647 .remove = i2c_nuvoton_remove,
648 .driver = {
649 .name = "tpm_i2c_nuvoton",
650 .pm = &i2c_nuvoton_pm_ops,
651 .of_match_table = of_match_ptr(i2c_nuvoton_of_match),
652 },
653 };
654
655 module_i2c_driver(i2c_nuvoton_driver);
656
657 MODULE_AUTHOR("Dan Morav <dan.morav@nuvoton.com>");
658 MODULE_DESCRIPTION("Nuvoton TPM I2C Driver");
659 MODULE_LICENSE("GPL");
660