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
37 static 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
72 struct ziirave_wdt_rev {
73 unsigned char major;
74 unsigned char minor;
75 };
76
77 struct 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
85 static int wdt_timeout;
86 module_param(wdt_timeout, int, 0);
87 MODULE_PARM_DESC(wdt_timeout, "Watchdog timeout in seconds");
88
89 static int reset_duration;
90 module_param(reset_duration, int, 0);
91 MODULE_PARM_DESC(reset_duration,
92 "Watchdog reset pulse duration in milliseconds");
93
94 static bool nowayout = WATCHDOG_NOWAYOUT;
95 module_param(nowayout, bool, 0);
96 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started default="
97 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
98
ziirave_wdt_revision(struct i2c_client * client,struct ziirave_wdt_rev * rev,u8 command)99 static 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
ziirave_wdt_set_state(struct watchdog_device * wdd,int state)119 static 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
ziirave_wdt_start(struct watchdog_device * wdd)126 static int ziirave_wdt_start(struct watchdog_device *wdd)
127 {
128 return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_ON);
129 }
130
ziirave_wdt_stop(struct watchdog_device * wdd)131 static int ziirave_wdt_stop(struct watchdog_device *wdd)
132 {
133 return ziirave_wdt_set_state(wdd, ZIIRAVE_STATE_OFF);
134 }
135
ziirave_wdt_ping(struct watchdog_device * wdd)136 static 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
ziirave_wdt_set_timeout(struct watchdog_device * wdd,unsigned int timeout)144 static 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
ziirave_wdt_get_timeleft(struct watchdog_device * wdd)157 static 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
ziirave_firm_read_ack(struct watchdog_device * wdd)169 static 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
ziirave_firm_set_read_addr(struct watchdog_device * wdd,u32 addr)183 static 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
ziirave_firm_addr_readonly(u32 addr)196 static 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 */
__ziirave_firm_write_pkt(struct watchdog_device * wdd,u32 addr,const u8 * data,u8 len)214 static 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
ziirave_firm_write_pkt(struct watchdog_device * wdd,u32 addr,const u8 * data,u8 len)269 static 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
ziirave_firm_verify(struct watchdog_device * wdd,const struct firmware * fw)293 static 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 (len > sizeof(data))
306 return -EINVAL;
307
308 if (ziirave_firm_addr_readonly(addr))
309 continue;
310
311 ret = ziirave_firm_set_read_addr(wdd, addr);
312 if (ret) {
313 dev_err(&client->dev,
314 "Failed to send SET_READ_ADDR command: %d\n",
315 ret);
316 return ret;
317 }
318
319 for (i = 0; i < len; i++) {
320 ret = i2c_smbus_read_byte_data(client,
321 ZIIRAVE_CMD_DOWNLOAD_READ_BYTE);
322 if (ret < 0) {
323 dev_err(&client->dev,
324 "Failed to READ DATA: %d\n", ret);
325 return ret;
326 }
327 data[i] = ret;
328 }
329
330 if (memcmp(data, rec->data, len)) {
331 dev_err(&client->dev,
332 "Firmware mismatch at address 0x%04x\n", addr);
333 return -EINVAL;
334 }
335 }
336
337 return 0;
338 }
339
ziirave_firm_upload(struct watchdog_device * wdd,const struct firmware * fw)340 static int ziirave_firm_upload(struct watchdog_device *wdd,
341 const struct firmware *fw)
342 {
343 struct i2c_client *client = to_i2c_client(wdd->parent);
344 const struct ihex_binrec *rec;
345 int ret;
346
347 ret = i2c_smbus_write_byte_data(client,
348 ZIIRAVE_CMD_JUMP_TO_BOOTLOADER,
349 ZIIRAVE_CMD_JUMP_TO_BOOTLOADER_MAGIC);
350 if (ret) {
351 dev_err(&client->dev, "Failed to jump to bootloader\n");
352 return ret;
353 }
354
355 msleep(500);
356
357 ret = i2c_smbus_write_byte(client, ZIIRAVE_CMD_DOWNLOAD_START);
358 if (ret) {
359 dev_err(&client->dev, "Failed to start download\n");
360 return ret;
361 }
362
363 ret = ziirave_firm_read_ack(wdd);
364 if (ret) {
365 dev_err(&client->dev, "No ACK for start download\n");
366 return ret;
367 }
368
369 msleep(500);
370
371 for (rec = (void *)fw->data; rec; rec = ihex_next_binrec(rec)) {
372 ret = ziirave_firm_write_pkt(wdd, be32_to_cpu(rec->addr),
373 rec->data, be16_to_cpu(rec->len));
374 if (ret)
375 return ret;
376 }
377
378 /*
379 * Finish firmware download process by sending a zero length
380 * payload
381 */
382 ret = ziirave_firm_write_pkt(wdd, 0, NULL, 0);
383 if (ret) {
384 dev_err(&client->dev, "Failed to send EMPTY packet: %d\n", ret);
385 return ret;
386 }
387
388 /* This sleep seems to be required */
389 msleep(20);
390
391 /* Start firmware verification */
392 ret = ziirave_firm_verify(wdd, fw);
393 if (ret) {
394 dev_err(&client->dev,
395 "Failed to verify firmware: %d\n", ret);
396 return ret;
397 }
398
399 /* End download operation */
400 ret = i2c_smbus_write_byte(client, ZIIRAVE_CMD_DOWNLOAD_END);
401 if (ret) {
402 dev_err(&client->dev,
403 "Failed to end firmware download: %d\n", ret);
404 return ret;
405 }
406
407 /* Reset the processor */
408 ret = i2c_smbus_write_byte_data(client,
409 ZIIRAVE_CMD_RESET_PROCESSOR,
410 ZIIRAVE_CMD_RESET_PROCESSOR_MAGIC);
411 if (ret) {
412 dev_err(&client->dev,
413 "Failed to reset the watchdog: %d\n", ret);
414 return ret;
415 }
416
417 msleep(500);
418
419 return 0;
420 }
421
422 static const struct watchdog_info ziirave_wdt_info = {
423 .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
424 .identity = "RAVE Switch Watchdog",
425 };
426
427 static const struct watchdog_ops ziirave_wdt_ops = {
428 .owner = THIS_MODULE,
429 .start = ziirave_wdt_start,
430 .stop = ziirave_wdt_stop,
431 .ping = ziirave_wdt_ping,
432 .set_timeout = ziirave_wdt_set_timeout,
433 .get_timeleft = ziirave_wdt_get_timeleft,
434 };
435
ziirave_wdt_sysfs_show_firm(struct device * dev,struct device_attribute * attr,char * buf)436 static ssize_t ziirave_wdt_sysfs_show_firm(struct device *dev,
437 struct device_attribute *attr,
438 char *buf)
439 {
440 struct i2c_client *client = to_i2c_client(dev->parent);
441 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
442 int ret;
443
444 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
445 if (ret)
446 return ret;
447
448 ret = sysfs_emit(buf, "02.%02u.%02u\n",
449 w_priv->firmware_rev.major,
450 w_priv->firmware_rev.minor);
451
452 mutex_unlock(&w_priv->sysfs_mutex);
453
454 return ret;
455 }
456
457 static DEVICE_ATTR(firmware_version, S_IRUGO, ziirave_wdt_sysfs_show_firm,
458 NULL);
459
ziirave_wdt_sysfs_show_boot(struct device * dev,struct device_attribute * attr,char * buf)460 static ssize_t ziirave_wdt_sysfs_show_boot(struct device *dev,
461 struct device_attribute *attr,
462 char *buf)
463 {
464 struct i2c_client *client = to_i2c_client(dev->parent);
465 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
466 int ret;
467
468 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
469 if (ret)
470 return ret;
471
472 ret = sysfs_emit(buf, "01.%02u.%02u\n",
473 w_priv->bootloader_rev.major,
474 w_priv->bootloader_rev.minor);
475
476 mutex_unlock(&w_priv->sysfs_mutex);
477
478 return ret;
479 }
480
481 static DEVICE_ATTR(bootloader_version, S_IRUGO, ziirave_wdt_sysfs_show_boot,
482 NULL);
483
ziirave_wdt_sysfs_show_reason(struct device * dev,struct device_attribute * attr,char * buf)484 static ssize_t ziirave_wdt_sysfs_show_reason(struct device *dev,
485 struct device_attribute *attr,
486 char *buf)
487 {
488 struct i2c_client *client = to_i2c_client(dev->parent);
489 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
490 int ret;
491
492 ret = mutex_lock_interruptible(&w_priv->sysfs_mutex);
493 if (ret)
494 return ret;
495
496 ret = sysfs_emit(buf, "%s\n", ziirave_reasons[w_priv->reset_reason]);
497
498 mutex_unlock(&w_priv->sysfs_mutex);
499
500 return ret;
501 }
502
503 static DEVICE_ATTR(reset_reason, S_IRUGO, ziirave_wdt_sysfs_show_reason,
504 NULL);
505
ziirave_wdt_sysfs_store_firm(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)506 static ssize_t ziirave_wdt_sysfs_store_firm(struct device *dev,
507 struct device_attribute *attr,
508 const char *buf, size_t count)
509 {
510 struct i2c_client *client = to_i2c_client(dev->parent);
511 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
512 const struct firmware *fw;
513 int err;
514
515 err = request_ihex_firmware(&fw, ZIIRAVE_FW_NAME, dev);
516 if (err) {
517 dev_err(&client->dev, "Failed to request ihex firmware\n");
518 return err;
519 }
520
521 err = mutex_lock_interruptible(&w_priv->sysfs_mutex);
522 if (err)
523 goto release_firmware;
524
525 err = ziirave_firm_upload(&w_priv->wdd, fw);
526 if (err) {
527 dev_err(&client->dev, "The firmware update failed: %d\n", err);
528 goto unlock_mutex;
529 }
530
531 /* Update firmware version */
532 err = ziirave_wdt_revision(client, &w_priv->firmware_rev,
533 ZIIRAVE_WDT_FIRM_VER_MAJOR);
534 if (err) {
535 dev_err(&client->dev, "Failed to read firmware version: %d\n",
536 err);
537 goto unlock_mutex;
538 }
539
540 dev_info(&client->dev,
541 "Firmware updated to version 02.%02u.%02u\n",
542 w_priv->firmware_rev.major, w_priv->firmware_rev.minor);
543
544 /* Restore the watchdog timeout */
545 err = ziirave_wdt_set_timeout(&w_priv->wdd, w_priv->wdd.timeout);
546 if (err)
547 dev_err(&client->dev, "Failed to set timeout: %d\n", err);
548
549 unlock_mutex:
550 mutex_unlock(&w_priv->sysfs_mutex);
551
552 release_firmware:
553 release_firmware(fw);
554
555 return err ? err : count;
556 }
557
558 static DEVICE_ATTR(update_firmware, S_IWUSR, NULL,
559 ziirave_wdt_sysfs_store_firm);
560
561 static struct attribute *ziirave_wdt_attrs[] = {
562 &dev_attr_firmware_version.attr,
563 &dev_attr_bootloader_version.attr,
564 &dev_attr_reset_reason.attr,
565 &dev_attr_update_firmware.attr,
566 NULL
567 };
568 ATTRIBUTE_GROUPS(ziirave_wdt);
569
ziirave_wdt_init_duration(struct i2c_client * client)570 static int ziirave_wdt_init_duration(struct i2c_client *client)
571 {
572 int ret;
573
574 if (!reset_duration) {
575 /* See if the reset pulse duration is provided in an of_node */
576 if (!client->dev.of_node)
577 ret = -ENODEV;
578 else
579 ret = of_property_read_u32(client->dev.of_node,
580 "reset-duration-ms",
581 &reset_duration);
582 if (ret) {
583 dev_info(&client->dev,
584 "No reset pulse duration specified, using default\n");
585 return 0;
586 }
587 }
588
589 if (reset_duration < 1 || reset_duration > 255)
590 return -EINVAL;
591
592 dev_info(&client->dev, "Setting reset duration to %dms",
593 reset_duration);
594
595 return i2c_smbus_write_byte_data(client, ZIIRAVE_WDT_RESET_DURATION,
596 reset_duration);
597 }
598
ziirave_wdt_probe(struct i2c_client * client)599 static int ziirave_wdt_probe(struct i2c_client *client)
600 {
601 int ret;
602 struct ziirave_wdt_data *w_priv;
603 int val;
604
605 if (!i2c_check_functionality(client->adapter,
606 I2C_FUNC_SMBUS_BYTE |
607 I2C_FUNC_SMBUS_BYTE_DATA |
608 I2C_FUNC_SMBUS_WRITE_BLOCK_DATA))
609 return -ENODEV;
610
611 w_priv = devm_kzalloc(&client->dev, sizeof(*w_priv), GFP_KERNEL);
612 if (!w_priv)
613 return -ENOMEM;
614
615 mutex_init(&w_priv->sysfs_mutex);
616
617 w_priv->wdd.info = &ziirave_wdt_info;
618 w_priv->wdd.ops = &ziirave_wdt_ops;
619 w_priv->wdd.min_timeout = ZIIRAVE_TIMEOUT_MIN;
620 w_priv->wdd.max_timeout = ZIIRAVE_TIMEOUT_MAX;
621 w_priv->wdd.parent = &client->dev;
622 w_priv->wdd.groups = ziirave_wdt_groups;
623
624 watchdog_init_timeout(&w_priv->wdd, wdt_timeout, &client->dev);
625
626 /*
627 * The default value set in the watchdog should be perfectly valid, so
628 * pass that in if we haven't provided one via the module parameter or
629 * of property.
630 */
631 if (w_priv->wdd.timeout == 0) {
632 val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_TIMEOUT);
633 if (val < 0) {
634 dev_err(&client->dev, "Failed to read timeout\n");
635 return val;
636 }
637
638 if (val > ZIIRAVE_TIMEOUT_MAX ||
639 val < ZIIRAVE_TIMEOUT_MIN)
640 val = ZIIRAVE_TIMEOUT_DEFAULT;
641
642 w_priv->wdd.timeout = val;
643 }
644
645 ret = ziirave_wdt_set_timeout(&w_priv->wdd, w_priv->wdd.timeout);
646 if (ret) {
647 dev_err(&client->dev, "Failed to set timeout\n");
648 return ret;
649 }
650
651 dev_info(&client->dev, "Timeout set to %ds\n", w_priv->wdd.timeout);
652
653 watchdog_set_nowayout(&w_priv->wdd, nowayout);
654
655 i2c_set_clientdata(client, w_priv);
656
657 /* If in unconfigured state, set to stopped */
658 val = i2c_smbus_read_byte_data(client, ZIIRAVE_WDT_STATE);
659 if (val < 0) {
660 dev_err(&client->dev, "Failed to read state\n");
661 return val;
662 }
663
664 if (val == ZIIRAVE_STATE_INITIAL)
665 ziirave_wdt_stop(&w_priv->wdd);
666
667 ret = ziirave_wdt_init_duration(client);
668 if (ret) {
669 dev_err(&client->dev, "Failed to init duration\n");
670 return ret;
671 }
672
673 ret = ziirave_wdt_revision(client, &w_priv->firmware_rev,
674 ZIIRAVE_WDT_FIRM_VER_MAJOR);
675 if (ret) {
676 dev_err(&client->dev, "Failed to read firmware version\n");
677 return ret;
678 }
679
680 dev_info(&client->dev,
681 "Firmware version: 02.%02u.%02u\n",
682 w_priv->firmware_rev.major, w_priv->firmware_rev.minor);
683
684 ret = ziirave_wdt_revision(client, &w_priv->bootloader_rev,
685 ZIIRAVE_WDT_BOOT_VER_MAJOR);
686 if (ret) {
687 dev_err(&client->dev, "Failed to read bootloader version\n");
688 return ret;
689 }
690
691 dev_info(&client->dev,
692 "Bootloader version: 01.%02u.%02u\n",
693 w_priv->bootloader_rev.major, w_priv->bootloader_rev.minor);
694
695 w_priv->reset_reason = i2c_smbus_read_byte_data(client,
696 ZIIRAVE_WDT_RESET_REASON);
697 if (w_priv->reset_reason < 0) {
698 dev_err(&client->dev, "Failed to read reset reason\n");
699 return w_priv->reset_reason;
700 }
701
702 if (w_priv->reset_reason >= ARRAY_SIZE(ziirave_reasons) ||
703 !ziirave_reasons[w_priv->reset_reason]) {
704 dev_err(&client->dev, "Invalid reset reason\n");
705 return -ENODEV;
706 }
707
708 ret = watchdog_register_device(&w_priv->wdd);
709
710 return ret;
711 }
712
ziirave_wdt_remove(struct i2c_client * client)713 static void ziirave_wdt_remove(struct i2c_client *client)
714 {
715 struct ziirave_wdt_data *w_priv = i2c_get_clientdata(client);
716
717 watchdog_unregister_device(&w_priv->wdd);
718 }
719
720 static const struct i2c_device_id ziirave_wdt_id[] = {
721 { "rave-wdt" },
722 { }
723 };
724 MODULE_DEVICE_TABLE(i2c, ziirave_wdt_id);
725
726 static const struct of_device_id zrv_wdt_of_match[] = {
727 { .compatible = "zii,rave-wdt", },
728 { },
729 };
730 MODULE_DEVICE_TABLE(of, zrv_wdt_of_match);
731
732 static struct i2c_driver ziirave_wdt_driver = {
733 .driver = {
734 .name = "ziirave_wdt",
735 .of_match_table = zrv_wdt_of_match,
736 },
737 .probe = ziirave_wdt_probe,
738 .remove = ziirave_wdt_remove,
739 .id_table = ziirave_wdt_id,
740 };
741
742 module_i2c_driver(ziirave_wdt_driver);
743
744 MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.co.uk");
745 MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver");
746 MODULE_LICENSE("GPL");
747