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_device.h> |
23 | #include "tpm.h" |
24 | |
25 | /* I2C interface offsets */ |
26 | #define TPM_STS 0x00 |
27 | #define TPM_BURST_COUNT 0x01 |
28 | #define TPM_DATA_FIFO_W 0x20 |
29 | #define TPM_DATA_FIFO_R 0x40 |
30 | #define TPM_VID_DID_RID 0x60 |
31 | #define TPM_I2C_RETRIES 5 |
32 | /* |
33 | * I2C bus device maximum buffer size w/o counting I2C address or command |
34 | * i.e. max size required for I2C write is 34 = addr, command, 32 bytes data |
35 | */ |
36 | #define TPM_I2C_MAX_BUF_SIZE 32 |
37 | #define TPM_I2C_RETRY_COUNT 32 |
38 | #define TPM_I2C_BUS_DELAY 1000 /* usec */ |
39 | #define TPM_I2C_RETRY_DELAY_SHORT (2 * 1000) /* usec */ |
40 | #define TPM_I2C_RETRY_DELAY_LONG (10 * 1000) /* usec */ |
41 | #define TPM_I2C_DELAY_RANGE 300 /* usec */ |
42 | |
43 | #define OF_IS_TPM2 ((void *)1) |
44 | #define I2C_IS_TPM2 1 |
45 | |
46 | struct priv_data { |
47 | int irq; |
48 | unsigned int intrs; |
49 | wait_queue_head_t read_queue; |
50 | }; |
51 | |
52 | static s32 i2c_nuvoton_read_buf(struct i2c_client *client, u8 offset, u8 size, |
53 | u8 *data) |
54 | { |
55 | s32 status; |
56 | |
57 | status = i2c_smbus_read_i2c_block_data(client, command: offset, length: size, values: data); |
58 | dev_dbg(&client->dev, |
59 | "%s(offset=%u size=%u data=%*ph) -> sts=%d\n" , __func__, |
60 | offset, size, (int)size, data, status); |
61 | return status; |
62 | } |
63 | |
64 | static s32 i2c_nuvoton_write_buf(struct i2c_client *client, u8 offset, u8 size, |
65 | u8 *data) |
66 | { |
67 | s32 status; |
68 | |
69 | status = i2c_smbus_write_i2c_block_data(client, command: offset, length: size, values: data); |
70 | dev_dbg(&client->dev, |
71 | "%s(offset=%u size=%u data=%*ph) -> sts=%d\n" , __func__, |
72 | offset, size, (int)size, data, status); |
73 | return status; |
74 | } |
75 | |
76 | #define TPM_STS_VALID 0x80 |
77 | #define TPM_STS_COMMAND_READY 0x40 |
78 | #define TPM_STS_GO 0x20 |
79 | #define TPM_STS_DATA_AVAIL 0x10 |
80 | #define TPM_STS_EXPECT 0x08 |
81 | #define TPM_STS_RESPONSE_RETRY 0x02 |
82 | #define TPM_STS_ERR_VAL 0x07 /* bit2...bit0 reads always 0 */ |
83 | |
84 | #define TPM_I2C_SHORT_TIMEOUT 750 /* ms */ |
85 | #define TPM_I2C_LONG_TIMEOUT 2000 /* 2 sec */ |
86 | |
87 | /* read TPM_STS register */ |
88 | static u8 i2c_nuvoton_read_status(struct tpm_chip *chip) |
89 | { |
90 | struct i2c_client *client = to_i2c_client(chip->dev.parent); |
91 | s32 status; |
92 | u8 data; |
93 | |
94 | status = i2c_nuvoton_read_buf(client, TPM_STS, size: 1, data: &data); |
95 | if (status <= 0) { |
96 | dev_err(&chip->dev, "%s() error return %d\n" , __func__, |
97 | status); |
98 | data = TPM_STS_ERR_VAL; |
99 | } |
100 | |
101 | return data; |
102 | } |
103 | |
104 | /* write byte to TPM_STS register */ |
105 | static s32 i2c_nuvoton_write_status(struct i2c_client *client, u8 data) |
106 | { |
107 | s32 status; |
108 | int i; |
109 | |
110 | /* this causes the current command to be aborted */ |
111 | for (i = 0, status = -1; i < TPM_I2C_RETRY_COUNT && status < 0; i++) { |
112 | status = i2c_nuvoton_write_buf(client, TPM_STS, size: 1, data: &data); |
113 | if (status < 0) |
114 | usleep_range(TPM_I2C_BUS_DELAY, TPM_I2C_BUS_DELAY |
115 | + TPM_I2C_DELAY_RANGE); |
116 | } |
117 | return status; |
118 | } |
119 | |
120 | /* write commandReady to TPM_STS register */ |
121 | static void i2c_nuvoton_ready(struct tpm_chip *chip) |
122 | { |
123 | struct i2c_client *client = to_i2c_client(chip->dev.parent); |
124 | s32 status; |
125 | |
126 | /* this causes the current command to be aborted */ |
127 | status = i2c_nuvoton_write_status(client, TPM_STS_COMMAND_READY); |
128 | if (status < 0) |
129 | dev_err(&chip->dev, |
130 | "%s() fail to write TPM_STS.commandReady\n" , __func__); |
131 | } |
132 | |
133 | /* read burstCount field from TPM_STS register |
134 | * return -1 on fail to read */ |
135 | static int i2c_nuvoton_get_burstcount(struct i2c_client *client, |
136 | struct tpm_chip *chip) |
137 | { |
138 | unsigned long stop = jiffies + chip->timeout_d; |
139 | s32 status; |
140 | int burst_count = -1; |
141 | u8 data; |
142 | |
143 | /* wait for burstcount to be non-zero */ |
144 | do { |
145 | /* in I2C burstCount is 1 byte */ |
146 | status = i2c_nuvoton_read_buf(client, TPM_BURST_COUNT, size: 1, |
147 | data: &data); |
148 | if (status > 0 && data > 0) { |
149 | burst_count = min_t(u8, TPM_I2C_MAX_BUF_SIZE, data); |
150 | break; |
151 | } |
152 | usleep_range(TPM_I2C_BUS_DELAY, TPM_I2C_BUS_DELAY |
153 | + TPM_I2C_DELAY_RANGE); |
154 | } while (time_before(jiffies, stop)); |
155 | |
156 | return burst_count; |
157 | } |
158 | |
159 | /* |
160 | * WPCT301/NPCT501/NPCT6XX SINT# supports only dataAvail |
161 | * any call to this function which is not waiting for dataAvail will |
162 | * set queue to NULL to avoid waiting for interrupt |
163 | */ |
164 | static bool i2c_nuvoton_check_status(struct tpm_chip *chip, u8 mask, u8 value) |
165 | { |
166 | u8 status = i2c_nuvoton_read_status(chip); |
167 | return (status != TPM_STS_ERR_VAL) && ((status & mask) == value); |
168 | } |
169 | |
170 | static int i2c_nuvoton_wait_for_stat(struct tpm_chip *chip, u8 mask, u8 value, |
171 | u32 timeout, wait_queue_head_t *queue) |
172 | { |
173 | if ((chip->flags & TPM_CHIP_FLAG_IRQ) && queue) { |
174 | s32 rc; |
175 | struct priv_data *priv = dev_get_drvdata(dev: &chip->dev); |
176 | unsigned int cur_intrs = priv->intrs; |
177 | |
178 | enable_irq(irq: priv->irq); |
179 | rc = wait_event_interruptible_timeout(*queue, |
180 | cur_intrs != priv->intrs, |
181 | timeout); |
182 | if (rc > 0) |
183 | return 0; |
184 | /* At this point we know that the SINT pin is asserted, so we |
185 | * do not need to do i2c_nuvoton_check_status */ |
186 | } else { |
187 | unsigned long ten_msec, stop; |
188 | bool status_valid; |
189 | |
190 | /* check current status */ |
191 | status_valid = i2c_nuvoton_check_status(chip, mask, value); |
192 | if (status_valid) |
193 | return 0; |
194 | |
195 | /* use polling to wait for the event */ |
196 | ten_msec = jiffies + usecs_to_jiffies(TPM_I2C_RETRY_DELAY_LONG); |
197 | stop = jiffies + timeout; |
198 | do { |
199 | if (time_before(jiffies, ten_msec)) |
200 | usleep_range(TPM_I2C_RETRY_DELAY_SHORT, |
201 | TPM_I2C_RETRY_DELAY_SHORT |
202 | + TPM_I2C_DELAY_RANGE); |
203 | else |
204 | usleep_range(TPM_I2C_RETRY_DELAY_LONG, |
205 | TPM_I2C_RETRY_DELAY_LONG |
206 | + TPM_I2C_DELAY_RANGE); |
207 | status_valid = i2c_nuvoton_check_status(chip, mask, |
208 | value); |
209 | if (status_valid) |
210 | return 0; |
211 | } while (time_before(jiffies, stop)); |
212 | } |
213 | dev_err(&chip->dev, "%s(%02x, %02x) -> timeout\n" , __func__, mask, |
214 | value); |
215 | return -ETIMEDOUT; |
216 | } |
217 | |
218 | /* wait for dataAvail field to be set in the TPM_STS register */ |
219 | static int i2c_nuvoton_wait_for_data_avail(struct tpm_chip *chip, u32 timeout, |
220 | wait_queue_head_t *queue) |
221 | { |
222 | return i2c_nuvoton_wait_for_stat(chip, |
223 | TPM_STS_DATA_AVAIL | TPM_STS_VALID, |
224 | TPM_STS_DATA_AVAIL | TPM_STS_VALID, |
225 | timeout, queue); |
226 | } |
227 | |
228 | /* Read @count bytes into @buf from TPM_RD_FIFO register */ |
229 | static int i2c_nuvoton_recv_data(struct i2c_client *client, |
230 | struct tpm_chip *chip, u8 *buf, size_t count) |
231 | { |
232 | struct priv_data *priv = dev_get_drvdata(dev: &chip->dev); |
233 | s32 rc; |
234 | int burst_count, bytes2read, size = 0; |
235 | |
236 | while (size < count && |
237 | i2c_nuvoton_wait_for_data_avail(chip, |
238 | timeout: chip->timeout_c, |
239 | queue: &priv->read_queue) == 0) { |
240 | burst_count = i2c_nuvoton_get_burstcount(client, chip); |
241 | if (burst_count < 0) { |
242 | dev_err(&chip->dev, |
243 | "%s() fail to read burstCount=%d\n" , __func__, |
244 | burst_count); |
245 | return -EIO; |
246 | } |
247 | bytes2read = min_t(size_t, burst_count, count - size); |
248 | rc = i2c_nuvoton_read_buf(client, TPM_DATA_FIFO_R, |
249 | size: bytes2read, data: &buf[size]); |
250 | if (rc < 0) { |
251 | dev_err(&chip->dev, |
252 | "%s() fail on i2c_nuvoton_read_buf()=%d\n" , |
253 | __func__, rc); |
254 | return -EIO; |
255 | } |
256 | dev_dbg(&chip->dev, "%s(%d):" , __func__, bytes2read); |
257 | size += bytes2read; |
258 | } |
259 | |
260 | return size; |
261 | } |
262 | |
263 | /* Read TPM command results */ |
264 | static int i2c_nuvoton_recv(struct tpm_chip *chip, u8 *buf, size_t count) |
265 | { |
266 | struct priv_data *priv = dev_get_drvdata(dev: &chip->dev); |
267 | struct device *dev = chip->dev.parent; |
268 | struct i2c_client *client = to_i2c_client(dev); |
269 | s32 rc; |
270 | int status; |
271 | int burst_count; |
272 | int retries; |
273 | int size = 0; |
274 | u32 expected; |
275 | |
276 | if (count < TPM_HEADER_SIZE) { |
277 | i2c_nuvoton_ready(chip); /* return to idle */ |
278 | dev_err(dev, "%s() count < header size\n" , __func__); |
279 | return -EIO; |
280 | } |
281 | for (retries = 0; retries < TPM_I2C_RETRIES; retries++) { |
282 | if (retries > 0) { |
283 | /* if this is not the first trial, set responseRetry */ |
284 | i2c_nuvoton_write_status(client, |
285 | TPM_STS_RESPONSE_RETRY); |
286 | } |
287 | /* |
288 | * read first available (> 10 bytes), including: |
289 | * tag, paramsize, and result |
290 | */ |
291 | status = i2c_nuvoton_wait_for_data_avail( |
292 | chip, timeout: chip->timeout_c, queue: &priv->read_queue); |
293 | if (status != 0) { |
294 | dev_err(dev, "%s() timeout on dataAvail\n" , __func__); |
295 | size = -ETIMEDOUT; |
296 | continue; |
297 | } |
298 | burst_count = i2c_nuvoton_get_burstcount(client, chip); |
299 | if (burst_count < 0) { |
300 | dev_err(dev, "%s() fail to get burstCount\n" , __func__); |
301 | size = -EIO; |
302 | continue; |
303 | } |
304 | size = i2c_nuvoton_recv_data(client, chip, buf, |
305 | count: burst_count); |
306 | if (size < TPM_HEADER_SIZE) { |
307 | dev_err(dev, "%s() fail to read header\n" , __func__); |
308 | size = -EIO; |
309 | continue; |
310 | } |
311 | /* |
312 | * convert number of expected bytes field from big endian 32 bit |
313 | * to machine native |
314 | */ |
315 | expected = be32_to_cpu(*(__be32 *) (buf + 2)); |
316 | if (expected > count || expected < size) { |
317 | dev_err(dev, "%s() expected > count\n" , __func__); |
318 | size = -EIO; |
319 | continue; |
320 | } |
321 | rc = i2c_nuvoton_recv_data(client, chip, buf: &buf[size], |
322 | count: expected - size); |
323 | size += rc; |
324 | if (rc < 0 || size < expected) { |
325 | dev_err(dev, "%s() fail to read remainder of result\n" , |
326 | __func__); |
327 | size = -EIO; |
328 | continue; |
329 | } |
330 | if (i2c_nuvoton_wait_for_stat( |
331 | chip, TPM_STS_VALID | TPM_STS_DATA_AVAIL, |
332 | TPM_STS_VALID, timeout: chip->timeout_c, |
333 | NULL)) { |
334 | dev_err(dev, "%s() error left over data\n" , __func__); |
335 | size = -ETIMEDOUT; |
336 | continue; |
337 | } |
338 | break; |
339 | } |
340 | i2c_nuvoton_ready(chip); |
341 | dev_dbg(&chip->dev, "%s() -> %d\n" , __func__, size); |
342 | return size; |
343 | } |
344 | |
345 | /* |
346 | * Send TPM command. |
347 | * |
348 | * If interrupts are used (signaled by an irq set in the vendor structure) |
349 | * tpm.c can skip polling for the data to be available as the interrupt is |
350 | * waited for here |
351 | */ |
352 | static int i2c_nuvoton_send(struct tpm_chip *chip, u8 *buf, size_t len) |
353 | { |
354 | struct priv_data *priv = dev_get_drvdata(dev: &chip->dev); |
355 | struct device *dev = chip->dev.parent; |
356 | struct i2c_client *client = to_i2c_client(dev); |
357 | u32 ordinal; |
358 | unsigned long duration; |
359 | size_t count = 0; |
360 | int burst_count, bytes2write, retries, rc = -EIO; |
361 | |
362 | for (retries = 0; retries < TPM_RETRY; retries++) { |
363 | i2c_nuvoton_ready(chip); |
364 | if (i2c_nuvoton_wait_for_stat(chip, TPM_STS_COMMAND_READY, |
365 | TPM_STS_COMMAND_READY, |
366 | timeout: chip->timeout_b, NULL)) { |
367 | dev_err(dev, "%s() timeout on commandReady\n" , |
368 | __func__); |
369 | rc = -EIO; |
370 | continue; |
371 | } |
372 | rc = 0; |
373 | while (count < len - 1) { |
374 | burst_count = i2c_nuvoton_get_burstcount(client, |
375 | chip); |
376 | if (burst_count < 0) { |
377 | dev_err(dev, "%s() fail get burstCount\n" , |
378 | __func__); |
379 | rc = -EIO; |
380 | break; |
381 | } |
382 | bytes2write = min_t(size_t, burst_count, |
383 | len - 1 - count); |
384 | rc = i2c_nuvoton_write_buf(client, TPM_DATA_FIFO_W, |
385 | size: bytes2write, data: &buf[count]); |
386 | if (rc < 0) { |
387 | dev_err(dev, "%s() fail i2cWriteBuf\n" , |
388 | __func__); |
389 | break; |
390 | } |
391 | dev_dbg(dev, "%s(%d):" , __func__, bytes2write); |
392 | count += bytes2write; |
393 | rc = i2c_nuvoton_wait_for_stat(chip, |
394 | TPM_STS_VALID | |
395 | TPM_STS_EXPECT, |
396 | TPM_STS_VALID | |
397 | TPM_STS_EXPECT, |
398 | timeout: chip->timeout_c, |
399 | NULL); |
400 | if (rc < 0) { |
401 | dev_err(dev, "%s() timeout on Expect\n" , |
402 | __func__); |
403 | rc = -ETIMEDOUT; |
404 | break; |
405 | } |
406 | } |
407 | if (rc < 0) |
408 | continue; |
409 | |
410 | /* write last byte */ |
411 | rc = i2c_nuvoton_write_buf(client, TPM_DATA_FIFO_W, size: 1, |
412 | data: &buf[count]); |
413 | if (rc < 0) { |
414 | dev_err(dev, "%s() fail to write last byte\n" , |
415 | __func__); |
416 | rc = -EIO; |
417 | continue; |
418 | } |
419 | dev_dbg(dev, "%s(last): %02x" , __func__, buf[count]); |
420 | rc = i2c_nuvoton_wait_for_stat(chip, |
421 | TPM_STS_VALID | TPM_STS_EXPECT, |
422 | TPM_STS_VALID, |
423 | timeout: chip->timeout_c, NULL); |
424 | if (rc) { |
425 | dev_err(dev, "%s() timeout on Expect to clear\n" , |
426 | __func__); |
427 | rc = -ETIMEDOUT; |
428 | continue; |
429 | } |
430 | break; |
431 | } |
432 | if (rc < 0) { |
433 | /* retries == TPM_RETRY */ |
434 | i2c_nuvoton_ready(chip); |
435 | return rc; |
436 | } |
437 | /* execute the TPM command */ |
438 | rc = i2c_nuvoton_write_status(client, TPM_STS_GO); |
439 | if (rc < 0) { |
440 | dev_err(dev, "%s() fail to write Go\n" , __func__); |
441 | i2c_nuvoton_ready(chip); |
442 | return rc; |
443 | } |
444 | ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); |
445 | duration = tpm_calc_ordinal_duration(chip, ordinal); |
446 | |
447 | rc = i2c_nuvoton_wait_for_data_avail(chip, timeout: duration, queue: &priv->read_queue); |
448 | if (rc) { |
449 | dev_err(dev, "%s() timeout command duration %ld\n" , |
450 | __func__, duration); |
451 | i2c_nuvoton_ready(chip); |
452 | return rc; |
453 | } |
454 | |
455 | dev_dbg(dev, "%s() -> %zd\n" , __func__, len); |
456 | return 0; |
457 | } |
458 | |
459 | static bool i2c_nuvoton_req_canceled(struct tpm_chip *chip, u8 status) |
460 | { |
461 | return (status == TPM_STS_COMMAND_READY); |
462 | } |
463 | |
464 | static const struct tpm_class_ops tpm_i2c = { |
465 | .flags = TPM_OPS_AUTO_STARTUP, |
466 | .status = i2c_nuvoton_read_status, |
467 | .recv = i2c_nuvoton_recv, |
468 | .send = i2c_nuvoton_send, |
469 | .cancel = i2c_nuvoton_ready, |
470 | .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID, |
471 | .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID, |
472 | .req_canceled = i2c_nuvoton_req_canceled, |
473 | }; |
474 | |
475 | /* The only purpose for the handler is to signal to any waiting threads that |
476 | * the interrupt is currently being asserted. The driver does not do any |
477 | * processing triggered by interrupts, and the chip provides no way to mask at |
478 | * the source (plus that would be slow over I2C). Run the IRQ as a one-shot, |
479 | * this means it cannot be shared. */ |
480 | static irqreturn_t i2c_nuvoton_int_handler(int dummy, void *dev_id) |
481 | { |
482 | struct tpm_chip *chip = dev_id; |
483 | struct priv_data *priv = dev_get_drvdata(dev: &chip->dev); |
484 | |
485 | priv->intrs++; |
486 | wake_up(&priv->read_queue); |
487 | disable_irq_nosync(irq: priv->irq); |
488 | return IRQ_HANDLED; |
489 | } |
490 | |
491 | static int get_vid(struct i2c_client *client, u32 *res) |
492 | { |
493 | static const u8 vid_did_rid_value[] = { 0x50, 0x10, 0xfe }; |
494 | u32 temp; |
495 | s32 rc; |
496 | |
497 | if (!i2c_check_functionality(adap: client->adapter, I2C_FUNC_SMBUS_BYTE_DATA)) |
498 | return -ENODEV; |
499 | rc = i2c_nuvoton_read_buf(client, TPM_VID_DID_RID, size: 4, data: (u8 *)&temp); |
500 | if (rc < 0) |
501 | return rc; |
502 | |
503 | /* check WPCT301 values - ignore RID */ |
504 | if (memcmp(p: &temp, q: vid_did_rid_value, size: sizeof(vid_did_rid_value))) { |
505 | /* |
506 | * f/w rev 2.81 has an issue where the VID_DID_RID is not |
507 | * reporting the right value. so give it another chance at |
508 | * offset 0x20 (FIFO_W). |
509 | */ |
510 | rc = i2c_nuvoton_read_buf(client, TPM_DATA_FIFO_W, size: 4, |
511 | data: (u8 *) (&temp)); |
512 | if (rc < 0) |
513 | return rc; |
514 | |
515 | /* check WPCT301 values - ignore RID */ |
516 | if (memcmp(p: &temp, q: vid_did_rid_value, |
517 | size: sizeof(vid_did_rid_value))) |
518 | return -ENODEV; |
519 | } |
520 | |
521 | *res = temp; |
522 | return 0; |
523 | } |
524 | |
525 | static int i2c_nuvoton_probe(struct i2c_client *client) |
526 | { |
527 | const struct i2c_device_id *id = i2c_client_get_device_id(client); |
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, res: &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(pdev: dev, ops: &tpm_i2c); |
542 | if (IS_ERR(ptr: chip)) |
543 | return PTR_ERR(ptr: chip); |
544 | |
545 | priv = devm_kzalloc(dev, size: sizeof(struct priv_data), GFP_KERNEL); |
546 | if (!priv) |
547 | return -ENOMEM; |
548 | |
549 | if (dev->of_node) { |
550 | const struct of_device_id *of_id; |
551 | |
552 | of_id = of_match_device(matches: dev->driver->of_match_table, dev); |
553 | if (of_id && of_id->data == OF_IS_TPM2) |
554 | chip->flags |= TPM_CHIP_FLAG_TPM2; |
555 | } else |
556 | if (id->driver_data == I2C_IS_TPM2) |
557 | chip->flags |= TPM_CHIP_FLAG_TPM2; |
558 | |
559 | init_waitqueue_head(&priv->read_queue); |
560 | |
561 | /* Default timeouts */ |
562 | chip->timeout_a = msecs_to_jiffies(TPM_I2C_SHORT_TIMEOUT); |
563 | chip->timeout_b = msecs_to_jiffies(TPM_I2C_LONG_TIMEOUT); |
564 | chip->timeout_c = msecs_to_jiffies(TPM_I2C_SHORT_TIMEOUT); |
565 | chip->timeout_d = msecs_to_jiffies(TPM_I2C_SHORT_TIMEOUT); |
566 | |
567 | dev_set_drvdata(dev: &chip->dev, data: priv); |
568 | |
569 | /* |
570 | * I2C intfcaps (interrupt capabilitieis) in the chip are hard coded to: |
571 | * TPM_INTF_INT_LEVEL_LOW | TPM_INTF_DATA_AVAIL_INT |
572 | * The IRQ should be set in the i2c_board_info (which is done |
573 | * automatically in of_i2c_register_devices, for device tree users */ |
574 | priv->irq = client->irq; |
575 | if (client->irq) { |
576 | dev_dbg(dev, "%s() priv->irq\n" , __func__); |
577 | rc = devm_request_irq(dev, irq: client->irq, |
578 | handler: i2c_nuvoton_int_handler, |
579 | IRQF_TRIGGER_LOW, |
580 | devname: dev_name(dev: &chip->dev), |
581 | dev_id: chip); |
582 | if (rc) { |
583 | dev_err(dev, "%s() Unable to request irq: %d for use\n" , |
584 | __func__, priv->irq); |
585 | priv->irq = 0; |
586 | } else { |
587 | chip->flags |= TPM_CHIP_FLAG_IRQ; |
588 | /* Clear any pending interrupt */ |
589 | i2c_nuvoton_ready(chip); |
590 | /* - wait for TPM_STS==0xA0 (stsValid, commandReady) */ |
591 | rc = i2c_nuvoton_wait_for_stat(chip, |
592 | TPM_STS_COMMAND_READY, |
593 | TPM_STS_COMMAND_READY, |
594 | timeout: chip->timeout_b, |
595 | NULL); |
596 | if (rc == 0) { |
597 | /* |
598 | * TIS is in ready state |
599 | * write dummy byte to enter reception state |
600 | * TPM_DATA_FIFO_W <- rc (0) |
601 | */ |
602 | rc = i2c_nuvoton_write_buf(client, |
603 | TPM_DATA_FIFO_W, |
604 | size: 1, data: (u8 *) (&rc)); |
605 | if (rc < 0) |
606 | return rc; |
607 | /* TPM_STS <- 0x40 (commandReady) */ |
608 | i2c_nuvoton_ready(chip); |
609 | } else { |
610 | /* |
611 | * timeout_b reached - command was |
612 | * aborted. TIS should now be in idle state - |
613 | * only TPM_STS_VALID should be set |
614 | */ |
615 | if (i2c_nuvoton_read_status(chip) != |
616 | TPM_STS_VALID) |
617 | return -EIO; |
618 | } |
619 | } |
620 | } |
621 | |
622 | return tpm_chip_register(chip); |
623 | } |
624 | |
625 | static void i2c_nuvoton_remove(struct i2c_client *client) |
626 | { |
627 | struct tpm_chip *chip = i2c_get_clientdata(client); |
628 | |
629 | tpm_chip_unregister(chip); |
630 | } |
631 | |
632 | static const struct i2c_device_id i2c_nuvoton_id[] = { |
633 | {"tpm_i2c_nuvoton" }, |
634 | {"tpm2_i2c_nuvoton" , .driver_data = I2C_IS_TPM2}, |
635 | {} |
636 | }; |
637 | MODULE_DEVICE_TABLE(i2c, i2c_nuvoton_id); |
638 | |
639 | #ifdef CONFIG_OF |
640 | static const struct of_device_id i2c_nuvoton_of_match[] = { |
641 | {.compatible = "nuvoton,npct501" }, |
642 | {.compatible = "winbond,wpct301" }, |
643 | {.compatible = "nuvoton,npct601" , .data = OF_IS_TPM2}, |
644 | {}, |
645 | }; |
646 | MODULE_DEVICE_TABLE(of, i2c_nuvoton_of_match); |
647 | #endif |
648 | |
649 | static SIMPLE_DEV_PM_OPS(i2c_nuvoton_pm_ops, tpm_pm_suspend, tpm_pm_resume); |
650 | |
651 | static struct i2c_driver i2c_nuvoton_driver = { |
652 | .id_table = i2c_nuvoton_id, |
653 | .probe = i2c_nuvoton_probe, |
654 | .remove = i2c_nuvoton_remove, |
655 | .driver = { |
656 | .name = "tpm_i2c_nuvoton" , |
657 | .pm = &i2c_nuvoton_pm_ops, |
658 | .of_match_table = of_match_ptr(i2c_nuvoton_of_match), |
659 | }, |
660 | }; |
661 | |
662 | module_i2c_driver(i2c_nuvoton_driver); |
663 | |
664 | MODULE_AUTHOR("Dan Morav (dan.morav@nuvoton.com)" ); |
665 | MODULE_DESCRIPTION("Nuvoton TPM I2C Driver" ); |
666 | MODULE_LICENSE("GPL" ); |
667 | |