2 * STMicroelectronics TPM Linux driver for TPM ST33ZP24
3 * Copyright (C) 2009 - 2016 STMicroelectronics
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, see <http://www.gnu.org/licenses/>.
19 #include <linux/module.h>
21 #include <linux/miscdevice.h>
22 #include <linux/kernel.h>
23 #include <linux/delay.h>
24 #include <linux/wait.h>
25 #include <linux/freezer.h>
26 #include <linux/string.h>
27 #include <linux/interrupt.h>
28 #include <linux/gpio.h>
29 #include <linux/sched.h>
30 #include <linux/uaccess.h>
32 #include <linux/slab.h>
37 #define TPM_ACCESS 0x0
39 #define TPM_DATA_FIFO 0x24
40 #define TPM_INTF_CAPABILITY 0x14
41 #define TPM_INT_STATUS 0x10
42 #define TPM_INT_ENABLE 0x08
46 enum st33zp24_access
{
47 TPM_ACCESS_VALID
= 0x80,
48 TPM_ACCESS_ACTIVE_LOCALITY
= 0x20,
49 TPM_ACCESS_REQUEST_PENDING
= 0x04,
50 TPM_ACCESS_REQUEST_USE
= 0x02,
53 enum st33zp24_status
{
55 TPM_STS_COMMAND_READY
= 0x40,
57 TPM_STS_DATA_AVAIL
= 0x10,
58 TPM_STS_DATA_EXPECT
= 0x08,
61 enum st33zp24_int_flags
{
62 TPM_GLOBAL_INT_ENABLE
= 0x80,
63 TPM_INTF_CMD_READY_INT
= 0x080,
64 TPM_INTF_FIFO_AVALAIBLE_INT
= 0x040,
65 TPM_INTF_WAKE_UP_READY_INT
= 0x020,
66 TPM_INTF_LOCALITY_CHANGE_INT
= 0x004,
67 TPM_INTF_STS_VALID_INT
= 0x002,
68 TPM_INTF_DATA_AVAIL_INT
= 0x001,
72 TIS_SHORT_TIMEOUT
= 750,
73 TIS_LONG_TIMEOUT
= 2000,
77 * clear_interruption clear the pending interrupt.
78 * @param: tpm_dev, the tpm device device.
79 * @return: the interrupt status value.
81 static u8
clear_interruption(struct st33zp24_dev
*tpm_dev
)
85 tpm_dev
->ops
->recv(tpm_dev
->phy_id
, TPM_INT_STATUS
, &interrupt
, 1);
86 tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_INT_STATUS
, &interrupt
, 1);
88 } /* clear_interruption() */
91 * st33zp24_cancel, cancel the current command execution or
92 * set STS to COMMAND READY.
93 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
95 static void st33zp24_cancel(struct tpm_chip
*chip
)
97 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
100 data
= TPM_STS_COMMAND_READY
;
101 tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_STS
, &data
, 1);
102 } /* st33zp24_cancel() */
105 * st33zp24_status return the TPM_STS register
106 * @param: chip, the tpm chip description
107 * @return: the TPM_STS register value.
109 static u8
st33zp24_status(struct tpm_chip
*chip
)
111 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
114 tpm_dev
->ops
->recv(tpm_dev
->phy_id
, TPM_STS
, &data
, 1);
116 } /* st33zp24_status() */
119 * check_locality if the locality is active
120 * @param: chip, the tpm chip description
121 * @return: the active locality or -EACCESS.
123 static int check_locality(struct tpm_chip
*chip
)
125 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
129 status
= tpm_dev
->ops
->recv(tpm_dev
->phy_id
, TPM_ACCESS
, &data
, 1);
130 if (status
&& (data
&
131 (TPM_ACCESS_ACTIVE_LOCALITY
| TPM_ACCESS_VALID
)) ==
132 (TPM_ACCESS_ACTIVE_LOCALITY
| TPM_ACCESS_VALID
))
133 return tpm_dev
->locality
;
136 } /* check_locality() */
139 * request_locality request the TPM locality
140 * @param: chip, the chip description
141 * @return: the active locality or negative value.
143 static int request_locality(struct tpm_chip
*chip
)
145 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
150 if (check_locality(chip
) == tpm_dev
->locality
)
151 return tpm_dev
->locality
;
153 data
= TPM_ACCESS_REQUEST_USE
;
154 ret
= tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_ACCESS
, &data
, 1);
158 stop
= jiffies
+ chip
->timeout_a
;
160 /* Request locality is usually effective after the request */
162 if (check_locality(chip
) >= 0)
163 return tpm_dev
->locality
;
165 } while (time_before(jiffies
, stop
));
167 /* could not get locality */
169 } /* request_locality() */
172 * release_locality release the active locality
173 * @param: chip, the tpm chip description.
175 static void release_locality(struct tpm_chip
*chip
)
177 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
180 data
= TPM_ACCESS_ACTIVE_LOCALITY
;
182 tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_ACCESS
, &data
, 1);
186 * get_burstcount return the burstcount value
187 * @param: chip, the chip description
188 * return: the burstcount or negative value.
190 static int get_burstcount(struct tpm_chip
*chip
)
192 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
194 int burstcnt
, status
;
197 stop
= jiffies
+ chip
->timeout_d
;
199 status
= tpm_dev
->ops
->recv(tpm_dev
->phy_id
, TPM_STS
+ 1,
205 status
= tpm_dev
->ops
->recv(tpm_dev
->phy_id
, TPM_STS
+ 2,
210 burstcnt
|= temp
<< 8;
214 } while (time_before(jiffies
, stop
));
216 } /* get_burstcount() */
220 * wait_for_tpm_stat_cond
221 * @param: chip, chip description
222 * @param: mask, expected mask value
223 * @param: check_cancel, does the command expected to be canceled ?
224 * @param: canceled, did we received a cancel request ?
225 * @return: true if status == mask or if the command is canceled.
226 * false in other cases.
228 static bool wait_for_tpm_stat_cond(struct tpm_chip
*chip
, u8 mask
,
229 bool check_cancel
, bool *canceled
)
231 u8 status
= chip
->ops
->status(chip
);
234 if ((status
& mask
) == mask
)
236 if (check_cancel
&& chip
->ops
->req_canceled(chip
, status
)) {
244 * wait_for_stat wait for a TPM_STS value
245 * @param: chip, the tpm chip description
246 * @param: mask, the value mask to wait
247 * @param: timeout, the timeout
248 * @param: queue, the wait queue.
249 * @param: check_cancel, does the command can be cancelled ?
250 * @return: the tpm status, 0 if success, -ETIME if timeout is reached.
252 static int wait_for_stat(struct tpm_chip
*chip
, u8 mask
, unsigned long timeout
,
253 wait_queue_head_t
*queue
, bool check_cancel
)
255 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
258 bool canceled
= false;
263 /* check current status */
264 status
= st33zp24_status(chip
);
265 if ((status
& mask
) == mask
)
268 stop
= jiffies
+ timeout
;
270 if (chip
->flags
& TPM_CHIP_FLAG_IRQ
) {
271 cur_intrs
= tpm_dev
->intrs
;
272 clear_interruption(tpm_dev
);
273 enable_irq(tpm_dev
->irq
);
276 if (ret
== -ERESTARTSYS
&& freezing(current
))
277 clear_thread_flag(TIF_SIGPENDING
);
279 timeout
= stop
- jiffies
;
280 if ((long) timeout
<= 0)
283 ret
= wait_event_interruptible_timeout(*queue
,
284 cur_intrs
!= tpm_dev
->intrs
,
286 clear_interruption(tpm_dev
);
287 condition
= wait_for_tpm_stat_cond(chip
, mask
,
288 check_cancel
, &canceled
);
289 if (ret
>= 0 && condition
) {
294 } while (ret
== -ERESTARTSYS
&& freezing(current
));
296 disable_irq_nosync(tpm_dev
->irq
);
301 status
= chip
->ops
->status(chip
);
302 if ((status
& mask
) == mask
)
304 } while (time_before(jiffies
, stop
));
308 } /* wait_for_stat() */
311 * recv_data receive data
312 * @param: chip, the tpm chip description
313 * @param: buf, the buffer where the data are received
314 * @param: count, the number of data to receive
315 * @return: the number of bytes read from TPM FIFO.
317 static int recv_data(struct tpm_chip
*chip
, u8
*buf
, size_t count
)
319 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
320 int size
= 0, burstcnt
, len
, ret
;
322 while (size
< count
&&
324 TPM_STS_DATA_AVAIL
| TPM_STS_VALID
,
326 &tpm_dev
->read_queue
, true) == 0) {
327 burstcnt
= get_burstcount(chip
);
330 len
= min_t(int, burstcnt
, count
- size
);
331 ret
= tpm_dev
->ops
->recv(tpm_dev
->phy_id
, TPM_DATA_FIFO
,
342 * tpm_ioserirq_handler the serirq irq handler
343 * @param: irq, the tpm chip description
344 * @param: dev_id, the description of the chip
345 * @return: the status of the handler.
347 static irqreturn_t
tpm_ioserirq_handler(int irq
, void *dev_id
)
349 struct tpm_chip
*chip
= dev_id
;
350 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
353 wake_up_interruptible(&tpm_dev
->read_queue
);
354 disable_irq_nosync(tpm_dev
->irq
);
357 } /* tpm_ioserirq_handler() */
360 * st33zp24_send send TPM commands through the I2C bus.
362 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h
363 * @param: buf, the buffer to send.
364 * @param: count, the number of bytes to send.
365 * @return: In case of success the number of bytes sent.
366 * In other case, a < 0 value describing the issue.
368 static int st33zp24_send(struct tpm_chip
*chip
, unsigned char *buf
,
371 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
372 u32 status
, i
, size
, ordinal
;
379 if (len
< TPM_HEADER_SIZE
)
382 ret
= request_locality(chip
);
386 status
= st33zp24_status(chip
);
387 if ((status
& TPM_STS_COMMAND_READY
) == 0) {
388 st33zp24_cancel(chip
);
390 (chip
, TPM_STS_COMMAND_READY
, chip
->timeout_b
,
391 &tpm_dev
->read_queue
, false) < 0) {
397 for (i
= 0; i
< len
- 1;) {
398 burstcnt
= get_burstcount(chip
);
401 size
= min_t(int, len
- i
- 1, burstcnt
);
402 ret
= tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_DATA_FIFO
,
410 status
= st33zp24_status(chip
);
411 if ((status
& TPM_STS_DATA_EXPECT
) == 0) {
416 ret
= tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_DATA_FIFO
,
421 status
= st33zp24_status(chip
);
422 if ((status
& TPM_STS_DATA_EXPECT
) != 0) {
428 ret
= tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_STS
, &data
, 1);
432 if (chip
->flags
& TPM_CHIP_FLAG_IRQ
) {
433 ordinal
= be32_to_cpu(*((__be32
*) (buf
+ 6)));
435 ret
= wait_for_stat(chip
, TPM_STS_DATA_AVAIL
| TPM_STS_VALID
,
436 tpm_calc_ordinal_duration(chip
, ordinal
),
437 &tpm_dev
->read_queue
, false);
444 st33zp24_cancel(chip
);
445 release_locality(chip
);
450 * st33zp24_recv received TPM response through TPM phy.
451 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
452 * @param: buf, the buffer to store datas.
453 * @param: count, the number of bytes to send.
454 * @return: In case of success the number of bytes received.
455 * In other case, a < 0 value describing the issue.
457 static int st33zp24_recv(struct tpm_chip
*chip
, unsigned char *buf
,
466 if (count
< TPM_HEADER_SIZE
) {
471 size
= recv_data(chip
, buf
, TPM_HEADER_SIZE
);
472 if (size
< TPM_HEADER_SIZE
) {
473 dev_err(&chip
->dev
, "Unable to read header\n");
477 expected
= be32_to_cpu(*(__be32
*)(buf
+ 2));
478 if (expected
> count
) {
483 size
+= recv_data(chip
, &buf
[TPM_HEADER_SIZE
],
484 expected
- TPM_HEADER_SIZE
);
485 if (size
< expected
) {
486 dev_err(&chip
->dev
, "Unable to read remainder of result\n");
491 st33zp24_cancel(chip
);
492 release_locality(chip
);
497 * st33zp24_req_canceled
498 * @param: chip, the tpm_chip description as specified in driver/char/tpm/tpm.h.
499 * @param: status, the TPM status.
500 * @return: Does TPM ready to compute a new command ? true.
502 static bool st33zp24_req_canceled(struct tpm_chip
*chip
, u8 status
)
504 return (status
== TPM_STS_COMMAND_READY
);
507 static const struct tpm_class_ops st33zp24_tpm
= {
508 .flags
= TPM_OPS_AUTO_STARTUP
,
509 .send
= st33zp24_send
,
510 .recv
= st33zp24_recv
,
511 .cancel
= st33zp24_cancel
,
512 .status
= st33zp24_status
,
513 .req_complete_mask
= TPM_STS_DATA_AVAIL
| TPM_STS_VALID
,
514 .req_complete_val
= TPM_STS_DATA_AVAIL
| TPM_STS_VALID
,
515 .req_canceled
= st33zp24_req_canceled
,
519 * st33zp24_probe initialize the TPM device
520 * @param: client, the i2c_client drescription (TPM I2C description).
521 * @param: id, the i2c_device_id struct.
522 * @return: 0 in case of success.
525 int st33zp24_probe(void *phy_id
, const struct st33zp24_phy_ops
*ops
,
526 struct device
*dev
, int irq
, int io_lpcpd
)
530 struct tpm_chip
*chip
;
531 struct st33zp24_dev
*tpm_dev
;
533 chip
= tpmm_chip_alloc(dev
, &st33zp24_tpm
);
535 return PTR_ERR(chip
);
537 tpm_dev
= devm_kzalloc(dev
, sizeof(struct st33zp24_dev
),
542 tpm_dev
->phy_id
= phy_id
;
544 dev_set_drvdata(&chip
->dev
, tpm_dev
);
546 chip
->timeout_a
= msecs_to_jiffies(TIS_SHORT_TIMEOUT
);
547 chip
->timeout_b
= msecs_to_jiffies(TIS_LONG_TIMEOUT
);
548 chip
->timeout_c
= msecs_to_jiffies(TIS_SHORT_TIMEOUT
);
549 chip
->timeout_d
= msecs_to_jiffies(TIS_SHORT_TIMEOUT
);
551 tpm_dev
->locality
= LOCALITY0
;
554 /* INTERRUPT Setup */
555 init_waitqueue_head(&tpm_dev
->read_queue
);
558 if (request_locality(chip
) != LOCALITY0
) {
560 goto _tpm_clean_answer
;
563 clear_interruption(tpm_dev
);
564 ret
= devm_request_irq(dev
, irq
, tpm_ioserirq_handler
,
565 IRQF_TRIGGER_HIGH
, "TPM SERIRQ management",
568 dev_err(&chip
->dev
, "TPM SERIRQ signals %d not available\n",
570 goto _tpm_clean_answer
;
573 intmask
|= TPM_INTF_CMD_READY_INT
574 | TPM_INTF_STS_VALID_INT
575 | TPM_INTF_DATA_AVAIL_INT
;
577 ret
= tpm_dev
->ops
->send(tpm_dev
->phy_id
, TPM_INT_ENABLE
,
580 goto _tpm_clean_answer
;
582 intmask
= TPM_GLOBAL_INT_ENABLE
;
583 ret
= tpm_dev
->ops
->send(tpm_dev
->phy_id
, (TPM_INT_ENABLE
+ 3),
586 goto _tpm_clean_answer
;
589 chip
->flags
|= TPM_CHIP_FLAG_IRQ
;
591 disable_irq_nosync(tpm_dev
->irq
);
594 return tpm_chip_register(chip
);
596 dev_info(&chip
->dev
, "TPM initialization fail\n");
599 EXPORT_SYMBOL(st33zp24_probe
);
602 * st33zp24_remove remove the TPM device
603 * @param: tpm_data, the tpm phy.
604 * @return: 0 in case of success.
606 int st33zp24_remove(struct tpm_chip
*chip
)
608 tpm_chip_unregister(chip
);
611 EXPORT_SYMBOL(st33zp24_remove
);
613 #ifdef CONFIG_PM_SLEEP
615 * st33zp24_pm_suspend suspend the TPM device
616 * @param: tpm_data, the tpm phy.
617 * @param: mesg, the power management message.
618 * @return: 0 in case of success.
620 int st33zp24_pm_suspend(struct device
*dev
)
622 struct tpm_chip
*chip
= dev_get_drvdata(dev
);
623 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
627 if (gpio_is_valid(tpm_dev
->io_lpcpd
))
628 gpio_set_value(tpm_dev
->io_lpcpd
, 0);
630 ret
= tpm_pm_suspend(dev
);
633 } /* st33zp24_pm_suspend() */
634 EXPORT_SYMBOL(st33zp24_pm_suspend
);
637 * st33zp24_pm_resume resume the TPM device
638 * @param: tpm_data, the tpm phy.
639 * @return: 0 in case of success.
641 int st33zp24_pm_resume(struct device
*dev
)
643 struct tpm_chip
*chip
= dev_get_drvdata(dev
);
644 struct st33zp24_dev
*tpm_dev
= dev_get_drvdata(&chip
->dev
);
647 if (gpio_is_valid(tpm_dev
->io_lpcpd
)) {
648 gpio_set_value(tpm_dev
->io_lpcpd
, 1);
649 ret
= wait_for_stat(chip
,
650 TPM_STS_VALID
, chip
->timeout_b
,
651 &tpm_dev
->read_queue
, false);
653 ret
= tpm_pm_resume(dev
);
655 tpm_do_selftest(chip
);
658 } /* st33zp24_pm_resume() */
659 EXPORT_SYMBOL(st33zp24_pm_resume
);
662 MODULE_AUTHOR("TPM support (TPMsupport@list.st.com)");
663 MODULE_DESCRIPTION("ST33ZP24 TPM 1.2 driver");
664 MODULE_VERSION("1.3.0");
665 MODULE_LICENSE("GPL");