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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2015 Zodiac Inflight Innovations
4 *
5 * Author: Martyn Welch <martyn.welch@collabora.co.uk>
6 *
7 * Based on twl4030_wdt.c by Timo Kokkonen <timo.t.kokkonen at nokia.com>:
8 *
9 * Copyright (C) Nokia Corporation
10 */
11
12#include <linux/delay.h>
13#include <linux/i2c.h>
14#include <linux/ihex.h>
15#include <linux/firmware.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/slab.h>
19#include <linux/sysfs.h>
20#include <linux/types.h>
21#include <linux/watchdog.h>
22
23#include <linux/unaligned.h>
24
25#define ZIIRAVE_TIMEOUT_MIN 3
26#define ZIIRAVE_TIMEOUT_MAX 255
27#define ZIIRAVE_TIMEOUT_DEFAULT 30
28
29#define ZIIRAVE_PING_VALUE 0x0
30
31#define ZIIRAVE_STATE_INITIAL 0x0
32#define ZIIRAVE_STATE_OFF 0x1
33#define ZIIRAVE_STATE_ON 0x2
34
35#define ZIIRAVE_FW_NAME "ziirave_wdt.fw"
36
37static char *ziirave_reasons[] = {"power cycle", "hw watchdog", NULL, NULL,
38 "host request", NULL, "illegal configuration",
39 "illegal instruction", "illegal trap",
40 "unknown"};
41
42#define ZIIRAVE_WDT_FIRM_VER_MAJOR 0x1
43#define ZIIRAVE_WDT_BOOT_VER_MAJOR 0x3
44#define ZIIRAVE_WDT_RESET_REASON 0x5
45#define ZIIRAVE_WDT_STATE 0x6
46#define ZIIRAVE_WDT_TIMEOUT 0x7
47#define ZIIRAVE_WDT_TIME_LEFT 0x8
48#define ZIIRAVE_WDT_PING 0x9
49#define ZIIRAVE_WDT_RESET_DURATION 0xa
50
51#define ZIIRAVE_FIRM_PKT_TOTAL_SIZE 20
52#define ZIIRAVE_FIRM_PKT_DATA_SIZE 16
53#define ZIIRAVE_FIRM_FLASH_MEMORY_START (2 * 0x1600)
54#define ZIIRAVE_FIRM_FLASH_MEMORY_END (2 * 0x2bbf)
55#define ZIIRAVE_FIRM_PAGE_SIZE 128
56
57/* Received and ready for next Download packet. */
58#define ZIIRAVE_FIRM_DOWNLOAD_ACK 1
59
60/* Firmware commands */
61#define ZIIRAVE_CMD_DOWNLOAD_START 0x10
62#define ZIIRAVE_CMD_DOWNLOAD_END 0x11
63#define ZIIRAVE_CMD_DOWNLOAD_SET_READ_ADDR 0x12
64#define ZIIRAVE_CMD_DOWNLOAD_READ_BYTE 0x13
65#define ZIIRAVE_CMD_RESET_PROCESSOR 0x0b
66#define ZIIRAVE_CMD_JUMP_TO_BOOTLOADER 0x0c
67#define ZIIRAVE_CMD_DOWNLOAD_PACKET 0x0e
68
69#define ZIIRAVE_CMD_JUMP_TO_BOOTLOADER_MAGIC 1
70#define ZIIRAVE_CMD_RESET_PROCESSOR_MAGIC 1
71
72struct ziirave_wdt_rev {
73 unsigned char major;
74 unsigned char minor;
75};
76
77struct ziirave_wdt_data {
78 struct mutex sysfs_mutex;
79 struct watchdog_device wdd;
80 struct ziirave_wdt_rev bootloader_rev;
81 struct ziirave_wdt_rev firmware_rev;
82 int reset_reason;
83};
84
85static int wdt_timeout;
86module_param(wdt_timeout, int, 0);
87MODULE_PARM_DESC(wdt_timeout, "Watchdog timeout in seconds");
88
89static int reset_duration;
90module_param(reset_duration, int, 0);
91MODULE_PARM_DESC(reset_duration,
92 "Watchdog reset pulse duration in milliseconds");
93
94static bool nowayout = WATCHDOG_NOWAYOUT;
95module_param(nowayout, bool, 0);
96MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started default="
97 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
98
99static int ziirave_wdt_revision(struct i2c_client *client,
100 struct ziirave_wdt_rev *rev, u8 command)
101{
102 int ret;
103
104 ret = i2c_smbus_read_byte_data(client, command);
105 if (ret < 0)
106 return ret;
107
108 rev->major = ret;
109
110 ret = i2c_smbus_read_byte_data(client, command + 1);
111 if (ret < 0)
112 return ret;
113
114 rev->minor = ret;
115
116 return 0;
117}
118
119static int ziirave_wdt_set_state(struct watchdog_device *wdd, int state)
120{
121 struct i2c_client *client = to_i2c_client(wdd->parent);
122
123 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_STATE, state);
124}
125
126static int ziirave_wdt_start(struct watchdog_device *wdd)
127{
128 return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_ON);
129}
130
131static int ziirave_wdt_stop(struct watchdog_device *wdd)
132{
133 return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_OFF);
134}
135
136static int ziirave_wdt_ping(struct watchdog_device *wdd)
137{
138 struct i2c_client *client = to_i2c_client(wdd->parent);
139
140 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_PING,
141 ZIIRAVE_PING_VALUE);
142}
143
144static int ziirave_wdt_set_timeout(struct watchdog_device *wdd,
145 unsigned int timeout)
146{
147 struct i2c_client *client = to_i2c_client(wdd->parent);
148 int ret;
149
150 ret = i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_TIMEOUT, timeout);
151 if (!ret)
152 wdd->timeout = timeout;
153
154 return ret;
155}
156
157static unsigned int ziirave_wdt_get_timeleft(struct watchdog_device *wdd)
158{
159 struct i2c_client *client = to_i2c_client(wdd->parent);
160 int ret;
161
162 ret = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIME_LEFT);
163 if (ret < 0)
164 ret = 0;
165
166 return ret;
167}
168
169static int ziirave_firm_read_ack(struct watchdog_device *wdd)
170{
171 struct i2c_client *client = to_i2c_client(wdd->parent);
172 int ret;
173
174 ret = i2c_smbus_read_byte(client);
175 if (ret < 0) {
176 dev_err(&client->dev, "Failed to read status byte\n");
177 return ret;
178 }
179
180 return ret == ZIIRAVE_FIRM_DOWNLOAD_ACK ? 0 : -EIO;
181}
182
183static int ziirave_firm_set_read_addr(struct watchdog_device *wdd, u32 addr)
184{
185 struct i2c_client *client = to_i2c_client(wdd->parent);
186 const u16 addr16 = (u16)addr / 2;
187 u8 address[2];
188
189 put_unaligned_le16(addr16, address);
190
191 return i2c_smbus_write_block_data(client,
192 ZIIRAVE_CMD_DOWNLOAD_SET_READ_ADDR,
193 sizeof(address), address);
194}
195
196static bool ziirave_firm_addr_readonly(u32 addr)
197{
198 return addr < ZIIRAVE_FIRM_FLASH_MEMORY_START ||
199 addr > ZIIRAVE_FIRM_FLASH_MEMORY_END;
200}
201
202/*
203 * ziirave_firm_write_pkt() - Build and write a firmware packet
204 *
205 * A packet to send to the firmware is composed by following bytes:
206 * Length | Addr0 | Addr1 | Data0 .. Data15 | Checksum |
207 * Where,
208 * Length: A data byte containing the length of the data.
209 * Addr0: Low byte of the address.
210 * Addr1: High byte of the address.
211 * Data0 .. Data15: Array of 16 bytes of data.
212 * Checksum: Checksum byte to verify data integrity.
213 */
214static int __ziirave_firm_write_pkt(struct watchdog_device *wdd,
215 u32 addr, const u8 *data, u8 len)
216{
217 const u16 addr16 = (u16)addr / 2;
218 struct i2c_client *client = to_i2c_client(wdd->parent);
219 u8 i, checksum = 0, packet[ZIIRAVE_FIRM_PKT_TOTAL_SIZE];
220 int ret;
221
222 /* Check max data size */
223 if (len > ZIIRAVE_FIRM_PKT_DATA_SIZE) {
224 dev_err(&client->dev, "Firmware packet too long (%d)\n",
225 len);
226 return -EMSGSIZE;
227 }
228
229 /*
230 * Ignore packets that are targeting program memory outisde of
231 * app partition, since they will be ignored by the
232 * bootloader. At the same time, we need to make sure we'll
233 * allow zero length packet that will be sent as the last step
234 * of firmware update
235 */
236 if (len && ziirave_firm_addr_readonly(addr))
237 return 0;
238
239 /* Packet length */
240 packet[0] = len;
241 /* Packet address */
242 put_unaligned_le16(addr16, packet + 1);
243
244 memcpy(packet + 3, data, len);
245 memset(packet + 3 + len, 0, ZIIRAVE_FIRM_PKT_DATA_SIZE - len);
246
247 /* Packet checksum */
248 for (i = 0; i < len + 3; i++)
249 checksum += packet[i];
250 packet[ZIIRAVE_FIRM_PKT_TOTAL_SIZE - 1] = checksum;
251
252 ret = i2c_smbus_write_block_data(client, ZIIRAVE_CMD_DOWNLOAD_PACKET,
253 sizeof(packet), packet);
254 if (ret) {
255 dev_err(&client->dev,
256 "Failed to send DOWNLOAD_PACKET: %d\n", ret);
257 return ret;
258 }
259
260 ret = ziirave_firm_read_ack(wdd);
261 if (ret)
262 dev_err(&client->dev,
263 "Failed to write firmware packet at address 0x%04x: %d\n",
264 addr, ret);
265
266 return ret;
267}
268
269static int ziirave_firm_write_pkt(struct watchdog_device *wdd,
270 u32 addr, const u8 *data, u8 len)
271{
272 const u8 max_write_len = ZIIRAVE_FIRM_PAGE_SIZE -
273 (addr - ALIGN_DOWN(addr, ZIIRAVE_FIRM_PAGE_SIZE));
274 int ret;
275
276 if (len > max_write_len) {
277 /*
278 * If data crossed page boundary we need to split this
279 * write in two
280 */
281 ret = __ziirave_firm_write_pkt(wdd, addr, data, max_write_len);
282 if (ret)
283 return ret;
284
285 addr += max_write_len;
286 data += max_write_len;
287 len -= max_write_len;
288 }
289
290 return __ziirave_firm_write_pkt(wdd, addr, data, len);
291}
292
293static int ziirave_firm_verify(struct watchdog_device *wdd,
294 const struct firmware *fw)
295{
296 struct i2c_client *client = to_i2c_client(wdd->parent);
297 const struct ihex_binrec *rec;
298 int i, ret;
299 u8 data[ZIIRAVE_FIRM_PKT_DATA_SIZE];
300
301 for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
302 const u16 len = be16_to_cpu(rec->len);
303 const u32 addr = be32_to_cpu(rec->addr);
304
305 if (ziirave_firm_addr_readonly(addr))
306 continue;
307
308 ret = ziirave_firm_set_read_addr(wdd, addr);
309 if (ret) {
310 dev_err(&client->dev,
311 "Failed to send SET_READ_ADDR command: %d\n",
312 ret);
313 return ret;
314 }
315
316 for (i = 0; i < len; i++) {
317 ret = i2c_smbus_read_byte_data(client,
318 ZIIRAVE_CMD_DOWNLOAD_READ_BYTE);
319 if (ret < 0) {
320 dev_err(&client->dev,
321 "Failed to READ DATA: %d\n", ret);
322 return ret;
323 }
324 data[i] = ret;
325 }
326
327 if (memcmp(data, rec->data, len)) {
328 dev_err(&client->dev,
329 "Firmware mismatch at address 0x%04x\n", addr);
330 return -EINVAL;
331 }
332 }
333
334 return 0;
335}
336
337static int ziirave_firm_upload(struct watchdog_device *wdd,
338 const struct firmware *fw)
339{
340 struct i2c_client *client = to_i2c_client(wdd->parent);
341 const struct ihex_binrec *rec;
342 int ret;
343
344 ret = i2c_smbus_write_byte_data(client,
345 ZIIRAVE_CMD_JUMP_TO_BOOTLOADER,
346 ZIIRAVE_CMD_JUMP_TO_BOOTLOADER_MAGIC);
347 if (ret) {
348 dev_err(&client->dev, "Failed to jump to bootloader\n");
349 return ret;
350 }
351
352 msleep(500);
353
354 ret = i2c_smbus_write_byte(client, ZIIRAVE_CMD_DOWNLOAD_START);
355 if (ret) {
356 dev_err(&client->dev, "Failed to start download\n");
357 return ret;
358 }
359
360 ret = ziirave_firm_read_ack(wdd);
361 if (ret) {
362 dev_err(&client->dev, "No ACK for start download\n");
363 return ret;
364 }
365
366 msleep(500);
367
368 for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
369 ret = ziirave_firm_write_pkt(wdd, be32_to_cpu(rec->addr),
370 rec->data, be16_to_cpu(rec->len));
371 if (ret)
372 return ret;
373 }
374
375 /*
376 * Finish firmware download process by sending a zero length
377 * payload
378 */
379 ret = ziirave_firm_write_pkt(wdd, 0, NULL, 0);
380 if (ret) {
381 dev_err(&client->dev, "Failed to send EMPTY packet: %d\n", ret);
382 return ret;
383 }
384
385 /* This sleep seems to be required */
386 msleep(20);
387
388 /* Start firmware verification */
389 ret = ziirave_firm_verify(wdd, fw);
390 if (ret) {
391 dev_err(&client->dev,
392 "Failed to verify firmware: %d\n", ret);
393 return ret;
394 }
395
396 /* End download operation */
397 ret = i2c_smbus_write_byte(client, ZIIRAVE_CMD_DOWNLOAD_END);
398 if (ret) {
399 dev_err(&client->dev,
400 "Failed to end firmware download: %d\n", ret);
401 return ret;
402 }
403
404 /* Reset the processor */
405 ret = i2c_smbus_write_byte_data(client,
406 ZIIRAVE_CMD_RESET_PROCESSOR,
407 ZIIRAVE_CMD_RESET_PROCESSOR_MAGIC);
408 if (ret) {
409 dev_err(&client->dev,
410 "Failed to reset the watchdog: %d\n", ret);
411 return ret;
412 }
413
414 msleep(500);
415
416 return 0;
417}
418
419static const struct watchdog_info ziirave_wdt_info = {
420 .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
421 .identity = "RAVE Switch Watchdog",
422};
423
424static const struct watchdog_ops ziirave_wdt_ops = {
425 .owner = THIS_MODULE,
426 .start = ziirave_wdt_start,
427 .stop = ziirave_wdt_stop,
428 .ping = ziirave_wdt_ping,
429 .set_timeout = ziirave_wdt_set_timeout,
430 .get_timeleft = ziirave_wdt_get_timeleft,
431};
432
433static ssize_t ziirave_wdt_sysfs_show_firm(struct device *dev,
434 struct device_attribute *attr,
435 char *buf)
436{
437 struct i2c_client *client = to_i2c_client(dev->parent);
438 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
439 int ret;
440
441 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
442 if (ret)
443 return ret;
444
445 ret = sysfs_emit(buf, "02.%02u.%02u\n",
446 w_priv->firmware_rev.major,
447 w_priv->firmware_rev.minor);
448
449 mutex_unlock(&w_priv->sysfs_mutex);
450
451 return ret;
452}
453
454static DEVICE_ATTR(firmware_version, S_IRUGO, ziirave_wdt_sysfs_show_firm,
455 NULL);
456
457static ssize_t ziirave_wdt_sysfs_show_boot(struct device *dev,
458 struct device_attribute *attr,
459 char *buf)
460{
461 struct i2c_client *client = to_i2c_client(dev->parent);
462 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
463 int ret;
464
465 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
466 if (ret)
467 return ret;
468
469 ret = sysfs_emit(buf, "01.%02u.%02u\n",
470 w_priv->bootloader_rev.major,
471 w_priv->bootloader_rev.minor);
472
473 mutex_unlock(&w_priv->sysfs_mutex);
474
475 return ret;
476}
477
478static DEVICE_ATTR(bootloader_version, S_IRUGO, ziirave_wdt_sysfs_show_boot,
479 NULL);
480
481static ssize_t ziirave_wdt_sysfs_show_reason(struct device *dev,
482 struct device_attribute *attr,
483 char *buf)
484{
485 struct i2c_client *client = to_i2c_client(dev->parent);
486 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
487 int ret;
488
489 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
490 if (ret)
491 return ret;
492
493 ret = sysfs_emit(buf, "%s\n", ziirave_reasons[w_priv->reset_reason]);
494
495 mutex_unlock(&w_priv->sysfs_mutex);
496
497 return ret;
498}
499
500static DEVICE_ATTR(reset_reason, S_IRUGO, ziirave_wdt_sysfs_show_reason,
501 NULL);
502
503static ssize_t ziirave_wdt_sysfs_store_firm(struct device *dev,
504 struct device_attribute *attr,
505 const char *buf, size_t count)
506{
507 struct i2c_client *client = to_i2c_client(dev->parent);
508 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
509 const struct firmware *fw;
510 int err;
511
512 err = request_ihex_firmware(&fw, ZIIRAVE_FW_NAME, dev);
513 if (err) {
514 dev_err(&client->dev, "Failed to request ihex firmware\n");
515 return err;
516 }
517
518 err = mutex_lock_interruptible(&w_priv->sysfs_mutex);
519 if (err)
520 goto release_firmware;
521
522 err = ziirave_firm_upload(&w_priv->wdd, fw);
523 if (err) {
524 dev_err(&client->dev, "The firmware update failed: %d\n", err);
525 goto unlock_mutex;
526 }
527
528 /* Update firmware version */
529 err = ziirave_wdt_revision(client, &w_priv->firmware_rev,
530 ZIIRAVE_WDT_FIRM_VER_MAJOR);
531 if (err) {
532 dev_err(&client->dev, "Failed to read firmware version: %d\n",
533 err);
534 goto unlock_mutex;
535 }
536
537 dev_info(&client->dev,
538 "Firmware updated to version 02.%02u.%02u\n",
539 w_priv->firmware_rev.major, w_priv->firmware_rev.minor);
540
541 /* Restore the watchdog timeout */
542 err = ziirave_wdt_set_timeout(&w_priv->wdd, w_priv->wdd.timeout);
543 if (err)
544 dev_err(&client->dev, "Failed to set timeout: %d\n", err);
545
546unlock_mutex:
547 mutex_unlock(&w_priv->sysfs_mutex);
548
549release_firmware:
550 release_firmware(fw);
551
552 return err ? err : count;
553}
554
555static DEVICE_ATTR(update_firmware, S_IWUSR, NULL,
556 ziirave_wdt_sysfs_store_firm);
557
558static struct attribute *ziirave_wdt_attrs[] = {
559 &dev_attr_firmware_version.attr,
560 &dev_attr_bootloader_version.attr,
561 &dev_attr_reset_reason.attr,
562 &dev_attr_update_firmware.attr,
563 NULL
564};
565ATTRIBUTE_GROUPS(ziirave_wdt);
566
567static int ziirave_wdt_init_duration(struct i2c_client *client)
568{
569 int ret;
570
571 if (!reset_duration) {
572 /* See if the reset pulse duration is provided in an of_node */
573 if (!client->dev.of_node)
574 ret = -ENODEV;
575 else
576 ret = of_property_read_u32(client->dev.of_node,
577 "reset-duration-ms",
578 &reset_duration);
579 if (ret) {
580 dev_info(&client->dev,
581 "No reset pulse duration specified, using default\n");
582 return 0;
583 }
584 }
585
586 if (reset_duration < 1 || reset_duration > 255)
587 return -EINVAL;
588
589 dev_info(&client->dev, "Setting reset duration to %dms",
590 reset_duration);
591
592 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_RESET_DURATION,
593 reset_duration);
594}
595
596static int ziirave_wdt_probe(struct i2c_client *client)
597{
598 int ret;
599 struct ziirave_wdt_data *w_priv;
600 int val;
601
602 if (!i2c_check_functionality(client->adapter,
603 I2C_FUNC_SMBUS_BYTE |
604 I2C_FUNC_SMBUS_BYTE_DATA |
605 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA))
606 return -ENODEV;
607
608 w_priv = devm_kzalloc(&client->dev, sizeof(*w_priv), GFP_KERNEL);
609 if (!w_priv)
610 return -ENOMEM;
611
612 mutex_init(&w_priv->sysfs_mutex);
613
614 w_priv->wdd.info = &ziirave_wdt_info;
615 w_priv->wdd.ops = &ziirave_wdt_ops;
616 w_priv->wdd.min_timeout = ZIIRAVE_TIMEOUT_MIN;
617 w_priv->wdd.max_timeout = ZIIRAVE_TIMEOUT_MAX;
618 w_priv->wdd.parent = &client->dev;
619 w_priv->wdd.groups = ziirave_wdt_groups;
620
621 watchdog_init_timeout(&w_priv->wdd, wdt_timeout, &client->dev);
622
623 /*
624 * The default value set in the watchdog should be perfectly valid, so
625 * pass that in if we haven't provided one via the module parameter or
626 * of property.
627 */
628 if (w_priv->wdd.timeout == 0) {
629 val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIMEOUT);
630 if (val < 0) {
631 dev_err(&client->dev, "Failed to read timeout\n");
632 return val;
633 }
634
635 if (val > ZIIRAVE_TIMEOUT_MAX ||
636 val < ZIIRAVE_TIMEOUT_MIN)
637 val = ZIIRAVE_TIMEOUT_DEFAULT;
638
639 w_priv->wdd.timeout = val;
640 }
641
642 ret = ziirave_wdt_set_timeout(&w_priv->wdd, w_priv->wdd.timeout);
643 if (ret) {
644 dev_err(&client->dev, "Failed to set timeout\n");
645 return ret;
646 }
647
648 dev_info(&client->dev, "Timeout set to %ds\n", w_priv->wdd.timeout);
649
650 watchdog_set_nowayout(&w_priv->wdd, nowayout);
651
652 i2c_set_clientdata(client, w_priv);
653
654 /* If in unconfigured state, set to stopped */
655 val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_STATE);
656 if (val < 0) {
657 dev_err(&client->dev, "Failed to read state\n");
658 return val;
659 }
660
661 if (val == ZIIRAVE_STATE_INITIAL)
662 ziirave_wdt_stop(&w_priv->wdd);
663
664 ret = ziirave_wdt_init_duration(client);
665 if (ret) {
666 dev_err(&client->dev, "Failed to init duration\n");
667 return ret;
668 }
669
670 ret = ziirave_wdt_revision(client, &w_priv->firmware_rev,
671 ZIIRAVE_WDT_FIRM_VER_MAJOR);
672 if (ret) {
673 dev_err(&client->dev, "Failed to read firmware version\n");
674 return ret;
675 }
676
677 dev_info(&client->dev,
678 "Firmware version: 02.%02u.%02u\n",
679 w_priv->firmware_rev.major, w_priv->firmware_rev.minor);
680
681 ret = ziirave_wdt_revision(client, &w_priv->bootloader_rev,
682 ZIIRAVE_WDT_BOOT_VER_MAJOR);
683 if (ret) {
684 dev_err(&client->dev, "Failed to read bootloader version\n");
685 return ret;
686 }
687
688 dev_info(&client->dev,
689 "Bootloader version: 01.%02u.%02u\n",
690 w_priv->bootloader_rev.major, w_priv->bootloader_rev.minor);
691
692 w_priv->reset_reason = i2c_smbus_read_byte_data(client,
693 ZIIRAVE_WDT_RESET_REASON);
694 if (w_priv->reset_reason < 0) {
695 dev_err(&client->dev, "Failed to read reset reason\n");
696 return w_priv->reset_reason;
697 }
698
699 if (w_priv->reset_reason >= ARRAY_SIZE(ziirave_reasons) ||
700 !ziirave_reasons[w_priv->reset_reason]) {
701 dev_err(&client->dev, "Invalid reset reason\n");
702 return -ENODEV;
703 }
704
705 ret = watchdog_register_device(&w_priv->wdd);
706
707 return ret;
708}
709
710static void ziirave_wdt_remove(struct i2c_client *client)
711{
712 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
713
714 watchdog_unregister_device(&w_priv->wdd);
715}
716
717static const struct i2c_device_id ziirave_wdt_id[] = {
718 { "rave-wdt" },
719 { }
720};
721MODULE_DEVICE_TABLE(i2c, ziirave_wdt_id);
722
723static const struct of_device_id zrv_wdt_of_match[] = {
724 { .compatible = "zii,rave-wdt", },
725 { },
726};
727MODULE_DEVICE_TABLE(of, zrv_wdt_of_match);
728
729static struct i2c_driver ziirave_wdt_driver = {
730 .driver = {
731 .name = "ziirave_wdt",
732 .of_match_table = zrv_wdt_of_match,
733 },
734 .probe = ziirave_wdt_probe,
735 .remove = ziirave_wdt_remove,
736 .id_table = ziirave_wdt_id,
737};
738
739module_i2c_driver(ziirave_wdt_driver);
740
741MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.co.uk");
742MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver");
743MODULE_LICENSE("GPL");
1/*
2 * Copyright (C) 2015 Zodiac Inflight Innovations
3 *
4 * Author: Martyn Welch <martyn.welch@collabora.co.uk>
5 *
6 * Based on twl4030_wdt.c by Timo Kokkonen <timo.t.kokkonen at nokia.com>:
7 *
8 * Copyright (C) Nokia Corporation
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 */
20
21#include <linux/delay.h>
22#include <linux/i2c.h>
23#include <linux/ihex.h>
24#include <linux/firmware.h>
25#include <linux/kernel.h>
26#include <linux/module.h>
27#include <linux/slab.h>
28#include <linux/sysfs.h>
29#include <linux/types.h>
30#include <linux/version.h>
31#include <linux/watchdog.h>
32
33#define ZIIRAVE_TIMEOUT_MIN 3
34#define ZIIRAVE_TIMEOUT_MAX 255
35
36#define ZIIRAVE_PING_VALUE 0x0
37
38#define ZIIRAVE_STATE_INITIAL 0x0
39#define ZIIRAVE_STATE_OFF 0x1
40#define ZIIRAVE_STATE_ON 0x2
41
42#define ZIIRAVE_FW_NAME "ziirave_wdt.fw"
43
44static char *ziirave_reasons[] = {"power cycle", "hw watchdog", NULL, NULL,
45 "host request", NULL, "illegal configuration",
46 "illegal instruction", "illegal trap",
47 "unknown"};
48
49#define ZIIRAVE_WDT_FIRM_VER_MAJOR 0x1
50#define ZIIRAVE_WDT_BOOT_VER_MAJOR 0x3
51#define ZIIRAVE_WDT_RESET_REASON 0x5
52#define ZIIRAVE_WDT_STATE 0x6
53#define ZIIRAVE_WDT_TIMEOUT 0x7
54#define ZIIRAVE_WDT_TIME_LEFT 0x8
55#define ZIIRAVE_WDT_PING 0x9
56#define ZIIRAVE_WDT_RESET_DURATION 0xa
57
58#define ZIIRAVE_FIRM_PKT_TOTAL_SIZE 20
59#define ZIIRAVE_FIRM_PKT_DATA_SIZE 16
60#define ZIIRAVE_FIRM_FLASH_MEMORY_START 0x1600
61#define ZIIRAVE_FIRM_FLASH_MEMORY_END 0x2bbf
62
63/* Received and ready for next Download packet. */
64#define ZIIRAVE_FIRM_DOWNLOAD_ACK 1
65/* Currently writing to flash. Retry Download status in a moment! */
66#define ZIIRAVE_FIRM_DOWNLOAD_BUSY 2
67
68/* Wait for ACK timeout in ms */
69#define ZIIRAVE_FIRM_WAIT_FOR_ACK_TIMEOUT 50
70
71/* Firmware commands */
72#define ZIIRAVE_CMD_DOWNLOAD_START 0x10
73#define ZIIRAVE_CMD_DOWNLOAD_END 0x11
74#define ZIIRAVE_CMD_DOWNLOAD_SET_READ_ADDR 0x12
75#define ZIIRAVE_CMD_DOWNLOAD_READ_BYTE 0x13
76#define ZIIRAVE_CMD_RESET_PROCESSOR 0x0b
77#define ZIIRAVE_CMD_JUMP_TO_BOOTLOADER 0x0c
78#define ZIIRAVE_CMD_DOWNLOAD_PACKET 0x0e
79
80struct ziirave_wdt_rev {
81 unsigned char major;
82 unsigned char minor;
83};
84
85struct ziirave_wdt_data {
86 struct mutex sysfs_mutex;
87 struct watchdog_device wdd;
88 struct ziirave_wdt_rev bootloader_rev;
89 struct ziirave_wdt_rev firmware_rev;
90 int reset_reason;
91};
92
93static int wdt_timeout;
94module_param(wdt_timeout, int, 0);
95MODULE_PARM_DESC(wdt_timeout, "Watchdog timeout in seconds");
96
97static int reset_duration;
98module_param(reset_duration, int, 0);
99MODULE_PARM_DESC(reset_duration,
100 "Watchdog reset pulse duration in milliseconds");
101
102static bool nowayout = WATCHDOG_NOWAYOUT;
103module_param(nowayout, bool, 0);
104MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started default="
105 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
106
107static int ziirave_wdt_revision(struct i2c_client *client,
108 struct ziirave_wdt_rev *rev, u8 command)
109{
110 int ret;
111
112 ret = i2c_smbus_read_byte_data(client, command);
113 if (ret < 0)
114 return ret;
115
116 rev->major = ret;
117
118 ret = i2c_smbus_read_byte_data(client, command + 1);
119 if (ret < 0)
120 return ret;
121
122 rev->minor = ret;
123
124 return 0;
125}
126
127static int ziirave_wdt_set_state(struct watchdog_device *wdd, int state)
128{
129 struct i2c_client *client = to_i2c_client(wdd->parent);
130
131 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_STATE, state);
132}
133
134static int ziirave_wdt_start(struct watchdog_device *wdd)
135{
136 return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_ON);
137}
138
139static int ziirave_wdt_stop(struct watchdog_device *wdd)
140{
141 return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_OFF);
142}
143
144static int ziirave_wdt_ping(struct watchdog_device *wdd)
145{
146 struct i2c_client *client = to_i2c_client(wdd->parent);
147
148 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_PING,
149 ZIIRAVE_PING_VALUE);
150}
151
152static int ziirave_wdt_set_timeout(struct watchdog_device *wdd,
153 unsigned int timeout)
154{
155 struct i2c_client *client = to_i2c_client(wdd->parent);
156 int ret;
157
158 ret = i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_TIMEOUT, timeout);
159 if (!ret)
160 wdd->timeout = timeout;
161
162 return ret;
163}
164
165static unsigned int ziirave_wdt_get_timeleft(struct watchdog_device *wdd)
166{
167 struct i2c_client *client = to_i2c_client(wdd->parent);
168 int ret;
169
170 ret = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIME_LEFT);
171 if (ret < 0)
172 ret = 0;
173
174 return ret;
175}
176
177static int ziirave_firm_wait_for_ack(struct watchdog_device *wdd)
178{
179 struct i2c_client *client = to_i2c_client(wdd->parent);
180 int ret;
181 unsigned long timeout;
182
183 timeout = jiffies + msecs_to_jiffies(ZIIRAVE_FIRM_WAIT_FOR_ACK_TIMEOUT);
184 do {
185 if (time_after(jiffies, timeout))
186 return -ETIMEDOUT;
187
188 usleep_range(5000, 10000);
189
190 ret = i2c_smbus_read_byte(client);
191 if (ret < 0) {
192 dev_err(&client->dev, "Failed to read byte\n");
193 return ret;
194 }
195 } while (ret == ZIIRAVE_FIRM_DOWNLOAD_BUSY);
196
197 return ret == ZIIRAVE_FIRM_DOWNLOAD_ACK ? 0 : -EIO;
198}
199
200static int ziirave_firm_set_read_addr(struct watchdog_device *wdd, u16 addr)
201{
202 struct i2c_client *client = to_i2c_client(wdd->parent);
203 u8 address[2];
204
205 address[0] = addr & 0xff;
206 address[1] = (addr >> 8) & 0xff;
207
208 return i2c_smbus_write_block_data(client,
209 ZIIRAVE_CMD_DOWNLOAD_SET_READ_ADDR,
210 ARRAY_SIZE(address), address);
211}
212
213static int ziirave_firm_write_block_data(struct watchdog_device *wdd,
214 u8 command, u8 length, const u8 *data,
215 bool wait_for_ack)
216{
217 struct i2c_client *client = to_i2c_client(wdd->parent);
218 int ret;
219
220 ret = i2c_smbus_write_block_data(client, command, length, data);
221 if (ret) {
222 dev_err(&client->dev,
223 "Failed to send command 0x%02x: %d\n", command, ret);
224 return ret;
225 }
226
227 if (wait_for_ack)
228 ret = ziirave_firm_wait_for_ack(wdd);
229
230 return ret;
231}
232
233static int ziirave_firm_write_byte(struct watchdog_device *wdd, u8 command,
234 u8 byte, bool wait_for_ack)
235{
236 return ziirave_firm_write_block_data(wdd, command, 1, &byte,
237 wait_for_ack);
238}
239
240/*
241 * ziirave_firm_write_pkt() - Build and write a firmware packet
242 *
243 * A packet to send to the firmware is composed by following bytes:
244 * Length | Addr0 | Addr1 | Data0 .. Data15 | Checksum |
245 * Where,
246 * Length: A data byte containing the length of the data.
247 * Addr0: Low byte of the address.
248 * Addr1: High byte of the address.
249 * Data0 .. Data15: Array of 16 bytes of data.
250 * Checksum: Checksum byte to verify data integrity.
251 */
252static int ziirave_firm_write_pkt(struct watchdog_device *wdd,
253 const struct ihex_binrec *rec)
254{
255 struct i2c_client *client = to_i2c_client(wdd->parent);
256 u8 i, checksum = 0, packet[ZIIRAVE_FIRM_PKT_TOTAL_SIZE];
257 int ret;
258 u16 addr;
259
260 memset(packet, 0, ARRAY_SIZE(packet));
261
262 /* Packet length */
263 packet[0] = (u8)be16_to_cpu(rec->len);
264 /* Packet address */
265 addr = (be32_to_cpu(rec->addr) & 0xffff) >> 1;
266 packet[1] = addr & 0xff;
267 packet[2] = (addr & 0xff00) >> 8;
268
269 /* Packet data */
270 if (be16_to_cpu(rec->len) > ZIIRAVE_FIRM_PKT_DATA_SIZE)
271 return -EMSGSIZE;
272 memcpy(packet + 3, rec->data, be16_to_cpu(rec->len));
273
274 /* Packet checksum */
275 for (i = 0; i < ZIIRAVE_FIRM_PKT_TOTAL_SIZE - 1; i++)
276 checksum += packet[i];
277 packet[ZIIRAVE_FIRM_PKT_TOTAL_SIZE - 1] = checksum;
278
279 ret = ziirave_firm_write_block_data(wdd, ZIIRAVE_CMD_DOWNLOAD_PACKET,
280 ARRAY_SIZE(packet), packet, true);
281 if (ret)
282 dev_err(&client->dev,
283 "Failed to write firmware packet at address 0x%04x: %d\n",
284 addr, ret);
285
286 return ret;
287}
288
289static int ziirave_firm_verify(struct watchdog_device *wdd,
290 const struct firmware *fw)
291{
292 struct i2c_client *client = to_i2c_client(wdd->parent);
293 const struct ihex_binrec *rec;
294 int i, ret;
295 u8 data[ZIIRAVE_FIRM_PKT_DATA_SIZE];
296 u16 addr;
297
298 for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
299 /* Zero length marks end of records */
300 if (!be16_to_cpu(rec->len))
301 break;
302
303 addr = (be32_to_cpu(rec->addr) & 0xffff) >> 1;
304 if (addr < ZIIRAVE_FIRM_FLASH_MEMORY_START ||
305 addr > ZIIRAVE_FIRM_FLASH_MEMORY_END)
306 continue;
307
308 ret = ziirave_firm_set_read_addr(wdd, addr);
309 if (ret) {
310 dev_err(&client->dev,
311 "Failed to send SET_READ_ADDR command: %d\n",
312 ret);
313 return ret;
314 }
315
316 for (i = 0; i < ARRAY_SIZE(data); i++) {
317 ret = i2c_smbus_read_byte_data(client,
318 ZIIRAVE_CMD_DOWNLOAD_READ_BYTE);
319 if (ret < 0) {
320 dev_err(&client->dev,
321 "Failed to READ DATA: %d\n", ret);
322 return ret;
323 }
324 data[i] = ret;
325 }
326
327 if (memcmp(data, rec->data, be16_to_cpu(rec->len))) {
328 dev_err(&client->dev,
329 "Firmware mismatch at address 0x%04x\n", addr);
330 return -EINVAL;
331 }
332 }
333
334 return 0;
335}
336
337static int ziirave_firm_upload(struct watchdog_device *wdd,
338 const struct firmware *fw)
339{
340 struct i2c_client *client = to_i2c_client(wdd->parent);
341 int ret, words_till_page_break;
342 const struct ihex_binrec *rec;
343 struct ihex_binrec *rec_new;
344
345 ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_JUMP_TO_BOOTLOADER, 1,
346 false);
347 if (ret)
348 return ret;
349
350 msleep(500);
351
352 ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_DOWNLOAD_START, 1, true);
353 if (ret)
354 return ret;
355
356 msleep(500);
357
358 for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
359 /* Zero length marks end of records */
360 if (!be16_to_cpu(rec->len))
361 break;
362
363 /* Check max data size */
364 if (be16_to_cpu(rec->len) > ZIIRAVE_FIRM_PKT_DATA_SIZE) {
365 dev_err(&client->dev, "Firmware packet too long (%d)\n",
366 be16_to_cpu(rec->len));
367 return -EMSGSIZE;
368 }
369
370 /* Calculate words till page break */
371 words_till_page_break = (64 - ((be32_to_cpu(rec->addr) >> 1) &
372 0x3f));
373 if ((be16_to_cpu(rec->len) >> 1) > words_till_page_break) {
374 /*
375 * Data in passes page boundary, so we need to split in
376 * two blocks of data. Create a packet with the first
377 * block of data.
378 */
379 rec_new = kzalloc(sizeof(struct ihex_binrec) +
380 (words_till_page_break << 1),
381 GFP_KERNEL);
382 if (!rec_new)
383 return -ENOMEM;
384
385 rec_new->len = cpu_to_be16(words_till_page_break << 1);
386 rec_new->addr = rec->addr;
387 memcpy(rec_new->data, rec->data,
388 be16_to_cpu(rec_new->len));
389
390 ret = ziirave_firm_write_pkt(wdd, rec_new);
391 kfree(rec_new);
392 if (ret)
393 return ret;
394
395 /* Create a packet with the second block of data */
396 rec_new = kzalloc(sizeof(struct ihex_binrec) +
397 be16_to_cpu(rec->len) -
398 (words_till_page_break << 1),
399 GFP_KERNEL);
400 if (!rec_new)
401 return -ENOMEM;
402
403 /* Remaining bytes */
404 rec_new->len = rec->len -
405 cpu_to_be16(words_till_page_break << 1);
406
407 rec_new->addr = cpu_to_be32(be32_to_cpu(rec->addr) +
408 (words_till_page_break << 1));
409
410 memcpy(rec_new->data,
411 rec->data + (words_till_page_break << 1),
412 be16_to_cpu(rec_new->len));
413
414 ret = ziirave_firm_write_pkt(wdd, rec_new);
415 kfree(rec_new);
416 if (ret)
417 return ret;
418 } else {
419 ret = ziirave_firm_write_pkt(wdd, rec);
420 if (ret)
421 return ret;
422 }
423 }
424
425 /* For end of download, the length field will be set to 0 */
426 rec_new = kzalloc(sizeof(struct ihex_binrec) + 1, GFP_KERNEL);
427 if (!rec_new)
428 return -ENOMEM;
429
430 ret = ziirave_firm_write_pkt(wdd, rec_new);
431 kfree(rec_new);
432 if (ret) {
433 dev_err(&client->dev, "Failed to send EMPTY packet: %d\n", ret);
434 return ret;
435 }
436
437 /* This sleep seems to be required */
438 msleep(20);
439
440 /* Start firmware verification */
441 ret = ziirave_firm_verify(wdd, fw);
442 if (ret) {
443 dev_err(&client->dev,
444 "Failed to verify firmware: %d\n", ret);
445 return ret;
446 }
447
448 /* End download operation */
449 ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_DOWNLOAD_END, 1, false);
450 if (ret)
451 return ret;
452
453 /* Reset the processor */
454 ret = ziirave_firm_write_byte(wdd, ZIIRAVE_CMD_RESET_PROCESSOR, 1,
455 false);
456 if (ret)
457 return ret;
458
459 msleep(500);
460
461 return 0;
462}
463
464static const struct watchdog_info ziirave_wdt_info = {
465 .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
466 .identity = "Zodiac RAVE Watchdog",
467};
468
469static const struct watchdog_ops ziirave_wdt_ops = {
470 .owner = THIS_MODULE,
471 .start = ziirave_wdt_start,
472 .stop = ziirave_wdt_stop,
473 .ping = ziirave_wdt_ping,
474 .set_timeout = ziirave_wdt_set_timeout,
475 .get_timeleft = ziirave_wdt_get_timeleft,
476};
477
478static ssize_t ziirave_wdt_sysfs_show_firm(struct device *dev,
479 struct device_attribute *attr,
480 char *buf)
481{
482 struct i2c_client *client = to_i2c_client(dev->parent);
483 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
484 int ret;
485
486 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
487 if (ret)
488 return ret;
489
490 ret = sprintf(buf, "02.%02u.%02u", w_priv->firmware_rev.major,
491 w_priv->firmware_rev.minor);
492
493 mutex_unlock(&w_priv->sysfs_mutex);
494
495 return ret;
496}
497
498static DEVICE_ATTR(firmware_version, S_IRUGO, ziirave_wdt_sysfs_show_firm,
499 NULL);
500
501static ssize_t ziirave_wdt_sysfs_show_boot(struct device *dev,
502 struct device_attribute *attr,
503 char *buf)
504{
505 struct i2c_client *client = to_i2c_client(dev->parent);
506 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
507 int ret;
508
509 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
510 if (ret)
511 return ret;
512
513 ret = sprintf(buf, "01.%02u.%02u", w_priv->bootloader_rev.major,
514 w_priv->bootloader_rev.minor);
515
516 mutex_unlock(&w_priv->sysfs_mutex);
517
518 return ret;
519}
520
521static DEVICE_ATTR(bootloader_version, S_IRUGO, ziirave_wdt_sysfs_show_boot,
522 NULL);
523
524static ssize_t ziirave_wdt_sysfs_show_reason(struct device *dev,
525 struct device_attribute *attr,
526 char *buf)
527{
528 struct i2c_client *client = to_i2c_client(dev->parent);
529 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
530 int ret;
531
532 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
533 if (ret)
534 return ret;
535
536 ret = sprintf(buf, "%s", ziirave_reasons[w_priv->reset_reason]);
537
538 mutex_unlock(&w_priv->sysfs_mutex);
539
540 return ret;
541}
542
543static DEVICE_ATTR(reset_reason, S_IRUGO, ziirave_wdt_sysfs_show_reason,
544 NULL);
545
546static ssize_t ziirave_wdt_sysfs_store_firm(struct device *dev,
547 struct device_attribute *attr,
548 const char *buf, size_t count)
549{
550 struct i2c_client *client = to_i2c_client(dev->parent);
551 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
552 const struct firmware *fw;
553 int err;
554
555 err = request_ihex_firmware(&fw, ZIIRAVE_FW_NAME, dev);
556 if (err) {
557 dev_err(&client->dev, "Failed to request ihex firmware\n");
558 return err;
559 }
560
561 err = mutex_lock_interruptible(&w_priv->sysfs_mutex);
562 if (err)
563 goto release_firmware;
564
565 err = ziirave_firm_upload(&w_priv->wdd, fw);
566 if (err) {
567 dev_err(&client->dev, "The firmware update failed: %d\n", err);
568 goto unlock_mutex;
569 }
570
571 /* Update firmware version */
572 err = ziirave_wdt_revision(client, &w_priv->firmware_rev,
573 ZIIRAVE_WDT_FIRM_VER_MAJOR);
574 if (err) {
575 dev_err(&client->dev, "Failed to read firmware version: %d\n",
576 err);
577 goto unlock_mutex;
578 }
579
580 dev_info(&client->dev, "Firmware updated to version 02.%02u.%02u\n",
581 w_priv->firmware_rev.major, w_priv->firmware_rev.minor);
582
583 /* Restore the watchdog timeout */
584 err = ziirave_wdt_set_timeout(&w_priv->wdd, w_priv->wdd.timeout);
585 if (err)
586 dev_err(&client->dev, "Failed to set timeout: %d\n", err);
587
588unlock_mutex:
589 mutex_unlock(&w_priv->sysfs_mutex);
590
591release_firmware:
592 release_firmware(fw);
593
594 return err ? err : count;
595}
596
597static DEVICE_ATTR(update_firmware, S_IWUSR, NULL,
598 ziirave_wdt_sysfs_store_firm);
599
600static struct attribute *ziirave_wdt_attrs[] = {
601 &dev_attr_firmware_version.attr,
602 &dev_attr_bootloader_version.attr,
603 &dev_attr_reset_reason.attr,
604 &dev_attr_update_firmware.attr,
605 NULL
606};
607ATTRIBUTE_GROUPS(ziirave_wdt);
608
609static int ziirave_wdt_init_duration(struct i2c_client *client)
610{
611 int ret;
612
613 if (!reset_duration) {
614 /* See if the reset pulse duration is provided in an of_node */
615 if (!client->dev.of_node)
616 ret = -ENODEV;
617 else
618 ret = of_property_read_u32(client->dev.of_node,
619 "reset-duration-ms",
620 &reset_duration);
621 if (ret) {
622 dev_info(&client->dev,
623 "Unable to set reset pulse duration, using default\n");
624 return 0;
625 }
626 }
627
628 if (reset_duration < 1 || reset_duration > 255)
629 return -EINVAL;
630
631 dev_info(&client->dev, "Setting reset duration to %dms",
632 reset_duration);
633
634 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_RESET_DURATION,
635 reset_duration);
636}
637
638static int ziirave_wdt_probe(struct i2c_client *client,
639 const struct i2c_device_id *id)
640{
641 int ret;
642 struct ziirave_wdt_data *w_priv;
643 int val;
644
645 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
646 return -ENODEV;
647
648 w_priv = devm_kzalloc(&client->dev, sizeof(*w_priv), GFP_KERNEL);
649 if (!w_priv)
650 return -ENOMEM;
651
652 mutex_init(&w_priv->sysfs_mutex);
653
654 w_priv->wdd.info = &ziirave_wdt_info;
655 w_priv->wdd.ops = &ziirave_wdt_ops;
656 w_priv->wdd.min_timeout = ZIIRAVE_TIMEOUT_MIN;
657 w_priv->wdd.max_timeout = ZIIRAVE_TIMEOUT_MAX;
658 w_priv->wdd.parent = &client->dev;
659 w_priv->wdd.groups = ziirave_wdt_groups;
660
661 ret = watchdog_init_timeout(&w_priv->wdd, wdt_timeout, &client->dev);
662 if (ret) {
663 dev_info(&client->dev,
664 "Unable to select timeout value, using default\n");
665 }
666
667 /*
668 * The default value set in the watchdog should be perfectly valid, so
669 * pass that in if we haven't provided one via the module parameter or
670 * of property.
671 */
672 if (w_priv->wdd.timeout == 0) {
673 val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIMEOUT);
674 if (val < 0)
675 return val;
676
677 if (val < ZIIRAVE_TIMEOUT_MIN)
678 return -ENODEV;
679
680 w_priv->wdd.timeout = val;
681 } else {
682 ret = ziirave_wdt_set_timeout(&w_priv->wdd,
683 w_priv->wdd.timeout);
684 if (ret)
685 return ret;
686
687 dev_info(&client->dev, "Timeout set to %ds.",
688 w_priv->wdd.timeout);
689 }
690
691 watchdog_set_nowayout(&w_priv->wdd, nowayout);
692
693 i2c_set_clientdata(client, w_priv);
694
695 /* If in unconfigured state, set to stopped */
696 val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_STATE);
697 if (val < 0)
698 return val;
699
700 if (val == ZIIRAVE_STATE_INITIAL)
701 ziirave_wdt_stop(&w_priv->wdd);
702
703 ret = ziirave_wdt_init_duration(client);
704 if (ret)
705 return ret;
706
707 ret = ziirave_wdt_revision(client, &w_priv->firmware_rev,
708 ZIIRAVE_WDT_FIRM_VER_MAJOR);
709 if (ret)
710 return ret;
711
712 ret = ziirave_wdt_revision(client, &w_priv->bootloader_rev,
713 ZIIRAVE_WDT_BOOT_VER_MAJOR);
714 if (ret)
715 return ret;
716
717 w_priv->reset_reason = i2c_smbus_read_byte_data(client,
718 ZIIRAVE_WDT_RESET_REASON);
719 if (w_priv->reset_reason < 0)
720 return w_priv->reset_reason;
721
722 if (w_priv->reset_reason >= ARRAY_SIZE(ziirave_reasons) ||
723 !ziirave_reasons[w_priv->reset_reason])
724 return -ENODEV;
725
726 ret = watchdog_register_device(&w_priv->wdd);
727
728 return ret;
729}
730
731static int ziirave_wdt_remove(struct i2c_client *client)
732{
733 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
734
735 watchdog_unregister_device(&w_priv->wdd);
736
737 return 0;
738}
739
740static struct i2c_device_id ziirave_wdt_id[] = {
741 { "rave-wdt", 0 },
742 { }
743};
744MODULE_DEVICE_TABLE(i2c, ziirave_wdt_id);
745
746static const struct of_device_id zrv_wdt_of_match[] = {
747 { .compatible = "zii,rave-wdt", },
748 { },
749};
750MODULE_DEVICE_TABLE(of, zrv_wdt_of_match);
751
752static struct i2c_driver ziirave_wdt_driver = {
753 .driver = {
754 .name = "ziirave_wdt",
755 .of_match_table = zrv_wdt_of_match,
756 },
757 .probe = ziirave_wdt_probe,
758 .remove = ziirave_wdt_remove,
759 .id_table = ziirave_wdt_id,
760};
761
762module_i2c_driver(ziirave_wdt_driver);
763
764MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.co.uk");
765MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver");
766MODULE_LICENSE("GPL");