1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * STMicroelectronics TPM Linux driver for TPM ST33ZP24
4 * Copyright (C) 2009 - 2016 STMicroelectronics
7 #include <linux/module.h>
9 #include <linux/kernel.h>
10 #include <linux/delay.h>
11 #include <linux/wait.h>
12 #include <linux/freezer.h>
13 #include <linux/string.h>
14 #include <linux/interrupt.h>
15 #include <linux/gpio.h>
16 #include <linux/sched.h>
17 #include <linux/uaccess.h>
19 #include <linux/slab.h>
24 #define TPM_ACCESS 0x0
26 #define TPM_DATA_FIFO 0x24
27 #define TPM_INTF_CAPABILITY 0x14
28 #define TPM_INT_STATUS 0x10
29 #define TPM_INT_ENABLE 0x08
33 enum st33zp24_access {
34 TPM_ACCESS_VALID = 0x80,
35 TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
36 TPM_ACCESS_REQUEST_PENDING = 0x04,
37 TPM_ACCESS_REQUEST_USE = 0x02,
40 enum st33zp24_status {
42 TPM_STS_COMMAND_READY = 0x40,
44 TPM_STS_DATA_AVAIL = 0x10,
45 TPM_STS_DATA_EXPECT = 0x08,
48 enum st33zp24_int_flags {
49 TPM_GLOBAL_INT_ENABLE = 0x80,
50 TPM_INTF_CMD_READY_INT = 0x080,
51 TPM_INTF_FIFO_AVALAIBLE_INT = 0x040,
52 TPM_INTF_WAKE_UP_READY_INT = 0x020,
53 TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
54 TPM_INTF_STS_VALID_INT = 0x002,
55 TPM_INTF_DATA_AVAIL_INT = 0x001,
59 TIS_SHORT_TIMEOUT = 750,
60 TIS_LONG_TIMEOUT = 2000,
64 * clear_interruption clear the pending interrupt.
65 * @param: tpm_dev, the tpm device device.
66 * @return: the interrupt status value.
68 static u8 clear_interruption(struct st33zp24_dev *tpm_dev)
72 tpm_dev->ops->recv(tpm_dev->phy_id, TPM_INT_STATUS, &interrupt, 1);
73 tpm_dev->ops->send(tpm_dev->phy_id, TPM_INT_STATUS, &interrupt, 1);
75 } /* clear_interruption() */
78 * st33zp24_cancel, cancel the current command execution or
79 * set STS to COMMAND READY.
80 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
82 static void st33zp24_cancel(struct tpm_chip *chip)
84 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
87 data = TPM_STS_COMMAND_READY;
88 tpm_dev->ops->send(tpm_dev->phy_id, TPM_STS, &data, 1);
89 } /* st33zp24_cancel() */
92 * st33zp24_status return the TPM_STS register
93 * @param: chip, the tpm chip description
94 * @return: the TPM_STS register value.
96 static u8 st33zp24_status(struct tpm_chip *chip)
98 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
101 tpm_dev->ops->recv(tpm_dev->phy_id, TPM_STS, &data, 1);
103 } /* st33zp24_status() */
106 * check_locality if the locality is active
107 * @param: chip, the tpm chip description
108 * @return: true if LOCALITY0 is active, otherwise false
110 static bool check_locality(struct tpm_chip *chip)
112 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
116 status = tpm_dev->ops->recv(tpm_dev->phy_id, TPM_ACCESS, &data, 1);
117 if (status && (data &
118 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
119 (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
123 } /* check_locality() */
126 * request_locality request the TPM locality
127 * @param: chip, the chip description
128 * @return: the active locality or negative value.
130 static int request_locality(struct tpm_chip *chip)
132 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
137 if (check_locality(chip))
138 return tpm_dev->locality;
140 data = TPM_ACCESS_REQUEST_USE;
141 ret = tpm_dev->ops->send(tpm_dev->phy_id, TPM_ACCESS, &data, 1);
145 stop = jiffies + chip->timeout_a;
147 /* Request locality is usually effective after the request */
149 if (check_locality(chip))
150 return tpm_dev->locality;
152 } while (time_before(jiffies, stop));
154 /* could not get locality */
156 } /* request_locality() */
159 * release_locality release the active locality
160 * @param: chip, the tpm chip description.
162 static void release_locality(struct tpm_chip *chip)
164 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
167 data = TPM_ACCESS_ACTIVE_LOCALITY;
169 tpm_dev->ops->send(tpm_dev->phy_id, TPM_ACCESS, &data, 1);
173 * get_burstcount return the burstcount value
174 * @param: chip, the chip description
175 * return: the burstcount or negative value.
177 static int get_burstcount(struct tpm_chip *chip)
179 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
181 int burstcnt, status;
184 stop = jiffies + chip->timeout_d;
186 status = tpm_dev->ops->recv(tpm_dev->phy_id, TPM_STS + 1,
192 status = tpm_dev->ops->recv(tpm_dev->phy_id, TPM_STS + 2,
197 burstcnt |= temp << 8;
201 } while (time_before(jiffies, stop));
203 } /* get_burstcount() */
207 * wait_for_tpm_stat_cond
208 * @param: chip, chip description
209 * @param: mask, expected mask value
210 * @param: check_cancel, does the command expected to be canceled ?
211 * @param: canceled, did we received a cancel request ?
212 * @return: true if status == mask or if the command is canceled.
213 * false in other cases.
215 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
216 bool check_cancel, bool *canceled)
218 u8 status = chip->ops->status(chip);
221 if ((status & mask) == mask)
223 if (check_cancel && chip->ops->req_canceled(chip, status)) {
231 * wait_for_stat wait for a TPM_STS value
232 * @param: chip, the tpm chip description
233 * @param: mask, the value mask to wait
234 * @param: timeout, the timeout
235 * @param: queue, the wait queue.
236 * @param: check_cancel, does the command can be cancelled ?
237 * @return: the tpm status, 0 if success, -ETIME if timeout is reached.
239 static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout,
240 wait_queue_head_t *queue, bool check_cancel)
242 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
245 bool canceled = false;
250 /* check current status */
251 status = st33zp24_status(chip);
252 if ((status & mask) == mask)
255 stop = jiffies + timeout;
257 if (chip->flags & TPM_CHIP_FLAG_IRQ) {
258 cur_intrs = tpm_dev->intrs;
259 clear_interruption(tpm_dev);
260 enable_irq(tpm_dev->irq);
263 if (ret == -ERESTARTSYS && freezing(current))
264 clear_thread_flag(TIF_SIGPENDING);
266 timeout = stop - jiffies;
267 if ((long) timeout <= 0)
270 ret = wait_event_interruptible_timeout(*queue,
271 cur_intrs != tpm_dev->intrs,
273 clear_interruption(tpm_dev);
274 condition = wait_for_tpm_stat_cond(chip, mask,
275 check_cancel, &canceled);
276 if (ret >= 0 && condition) {
281 } while (ret == -ERESTARTSYS && freezing(current));
283 disable_irq_nosync(tpm_dev->irq);
288 status = chip->ops->status(chip);
289 if ((status & mask) == mask)
291 } while (time_before(jiffies, stop));
295 } /* wait_for_stat() */
298 * recv_data receive data
299 * @param: chip, the tpm chip description
300 * @param: buf, the buffer where the data are received
301 * @param: count, the number of data to receive
302 * @return: the number of bytes read from TPM FIFO.
304 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
306 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
307 int size = 0, burstcnt, len, ret;
309 while (size < count &&
311 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
313 &tpm_dev->read_queue, true) == 0) {
314 burstcnt = get_burstcount(chip);
317 len = min_t(int, burstcnt, count - size);
318 ret = tpm_dev->ops->recv(tpm_dev->phy_id, TPM_DATA_FIFO,
329 * tpm_ioserirq_handler the serirq irq handler
330 * @param: irq, the tpm chip description
331 * @param: dev_id, the description of the chip
332 * @return: the status of the handler.
334 static irqreturn_t tpm_ioserirq_handler(int irq, void *dev_id)
336 struct tpm_chip *chip = dev_id;
337 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
340 wake_up_interruptible(&tpm_dev->read_queue);
341 disable_irq_nosync(tpm_dev->irq);
344 } /* tpm_ioserirq_handler() */
347 * st33zp24_send send TPM commands through the I2C bus.
349 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
350 * @param: buf, the buffer to send.
351 * @param: count, the number of bytes to send.
352 * @return: In case of success the number of bytes sent.
353 * In other case, a < 0 value describing the issue.
355 static int st33zp24_send(struct tpm_chip *chip, unsigned char *buf,
358 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
359 u32 status, i, size, ordinal;
364 if (len < TPM_HEADER_SIZE)
367 ret = request_locality(chip);
371 status = st33zp24_status(chip);
372 if ((status & TPM_STS_COMMAND_READY) == 0) {
373 st33zp24_cancel(chip);
375 (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
376 &tpm_dev->read_queue, false) < 0) {
382 for (i = 0; i < len - 1;) {
383 burstcnt = get_burstcount(chip);
386 size = min_t(int, len - i - 1, burstcnt);
387 ret = tpm_dev->ops->send(tpm_dev->phy_id, TPM_DATA_FIFO,
395 status = st33zp24_status(chip);
396 if ((status & TPM_STS_DATA_EXPECT) == 0) {
401 ret = tpm_dev->ops->send(tpm_dev->phy_id, TPM_DATA_FIFO,
406 status = st33zp24_status(chip);
407 if ((status & TPM_STS_DATA_EXPECT) != 0) {
413 ret = tpm_dev->ops->send(tpm_dev->phy_id, TPM_STS, &data, 1);
417 if (chip->flags & TPM_CHIP_FLAG_IRQ) {
418 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
420 ret = wait_for_stat(chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID,
421 tpm_calc_ordinal_duration(chip, ordinal),
422 &tpm_dev->read_queue, false);
429 st33zp24_cancel(chip);
430 release_locality(chip);
435 * st33zp24_recv received TPM response through TPM phy.
436 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
437 * @param: buf, the buffer to store datas.
438 * @param: count, the number of bytes to send.
439 * @return: In case of success the number of bytes received.
440 * In other case, a < 0 value describing the issue.
442 static int st33zp24_recv(struct tpm_chip *chip, unsigned char *buf,
451 if (count < TPM_HEADER_SIZE) {
456 size = recv_data(chip, buf, TPM_HEADER_SIZE);
457 if (size < TPM_HEADER_SIZE) {
458 dev_err(&chip->dev, "Unable to read header\n");
462 expected = be32_to_cpu(*(__be32 *)(buf + 2));
463 if (expected > count || expected < TPM_HEADER_SIZE) {
468 size += recv_data(chip, &buf[TPM_HEADER_SIZE],
469 expected - TPM_HEADER_SIZE);
470 if (size < expected) {
471 dev_err(&chip->dev, "Unable to read remainder of result\n");
476 st33zp24_cancel(chip);
477 release_locality(chip);
482 * st33zp24_req_canceled
483 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
484 * @param: status, the TPM status.
485 * @return: Does TPM ready to compute a new command ? true.
487 static bool st33zp24_req_canceled(struct tpm_chip *chip, u8 status)
489 return (status == TPM_STS_COMMAND_READY);
492 static const struct tpm_class_ops st33zp24_tpm = {
493 .flags = TPM_OPS_AUTO_STARTUP,
494 .send = st33zp24_send,
495 .recv = st33zp24_recv,
496 .cancel = st33zp24_cancel,
497 .status = st33zp24_status,
498 .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
499 .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
500 .req_canceled = st33zp24_req_canceled,
504 * st33zp24_probe initialize the TPM device
505 * @param: client, the i2c_client description (TPM I2C description).
506 * @param: id, the i2c_device_id struct.
507 * @return: 0 in case of success.
510 int st33zp24_probe(void *phy_id, const struct st33zp24_phy_ops *ops,
511 struct device *dev, int irq, int io_lpcpd)
515 struct tpm_chip *chip;
516 struct st33zp24_dev *tpm_dev;
518 chip = tpmm_chip_alloc(dev, &st33zp24_tpm);
520 return PTR_ERR(chip);
522 tpm_dev = devm_kzalloc(dev, sizeof(struct st33zp24_dev),
527 tpm_dev->phy_id = phy_id;
529 dev_set_drvdata(&chip->dev, tpm_dev);
531 chip->timeout_a = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
532 chip->timeout_b = msecs_to_jiffies(TIS_LONG_TIMEOUT);
533 chip->timeout_c = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
534 chip->timeout_d = msecs_to_jiffies(TIS_SHORT_TIMEOUT);
536 tpm_dev->locality = LOCALITY0;
539 /* INTERRUPT Setup */
540 init_waitqueue_head(&tpm_dev->read_queue);
543 if (request_locality(chip) != LOCALITY0) {
545 goto _tpm_clean_answer;
548 clear_interruption(tpm_dev);
549 ret = devm_request_irq(dev, irq, tpm_ioserirq_handler,
550 IRQF_TRIGGER_HIGH, "TPM SERIRQ management",
553 dev_err(&chip->dev, "TPM SERIRQ signals %d not available\n",
555 goto _tpm_clean_answer;
558 intmask |= TPM_INTF_CMD_READY_INT
559 | TPM_INTF_STS_VALID_INT
560 | TPM_INTF_DATA_AVAIL_INT;
562 ret = tpm_dev->ops->send(tpm_dev->phy_id, TPM_INT_ENABLE,
565 goto _tpm_clean_answer;
567 intmask = TPM_GLOBAL_INT_ENABLE;
568 ret = tpm_dev->ops->send(tpm_dev->phy_id, (TPM_INT_ENABLE + 3),
571 goto _tpm_clean_answer;
574 chip->flags |= TPM_CHIP_FLAG_IRQ;
576 disable_irq_nosync(tpm_dev->irq);
579 return tpm_chip_register(chip);
581 dev_info(&chip->dev, "TPM initialization fail\n");
584 EXPORT_SYMBOL(st33zp24_probe);
587 * st33zp24_remove remove the TPM device
588 * @param: tpm_data, the tpm phy.
589 * @return: 0 in case of success.
591 int st33zp24_remove(struct tpm_chip *chip)
593 tpm_chip_unregister(chip);
596 EXPORT_SYMBOL(st33zp24_remove);
598 #ifdef CONFIG_PM_SLEEP
600 * st33zp24_pm_suspend suspend the TPM device
601 * @param: tpm_data, the tpm phy.
602 * @param: mesg, the power management message.
603 * @return: 0 in case of success.
605 int st33zp24_pm_suspend(struct device *dev)
607 struct tpm_chip *chip = dev_get_drvdata(dev);
608 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
612 if (gpio_is_valid(tpm_dev->io_lpcpd))
613 gpio_set_value(tpm_dev->io_lpcpd, 0);
615 ret = tpm_pm_suspend(dev);
618 } /* st33zp24_pm_suspend() */
619 EXPORT_SYMBOL(st33zp24_pm_suspend);
622 * st33zp24_pm_resume resume the TPM device
623 * @param: tpm_data, the tpm phy.
624 * @return: 0 in case of success.
626 int st33zp24_pm_resume(struct device *dev)
628 struct tpm_chip *chip = dev_get_drvdata(dev);
629 struct st33zp24_dev *tpm_dev = dev_get_drvdata(&chip->dev);
632 if (gpio_is_valid(tpm_dev->io_lpcpd)) {
633 gpio_set_value(tpm_dev->io_lpcpd, 1);
634 ret = wait_for_stat(chip,
635 TPM_STS_VALID, chip->timeout_b,
636 &tpm_dev->read_queue, false);
638 ret = tpm_pm_resume(dev);
640 tpm1_do_selftest(chip);
643 } /* st33zp24_pm_resume() */
644 EXPORT_SYMBOL(st33zp24_pm_resume);
647 MODULE_AUTHOR("TPM support (TPMsupport@list.st.com)");
648 MODULE_DESCRIPTION("ST33ZP24 TPM 1.2 driver");
649 MODULE_VERSION("1.3.0");
650 MODULE_LICENSE("GPL");