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 (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
ziirave_firm_upload(struct watchdog_device * wdd,const struct firmware * fw)337 static 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
419 static const struct watchdog_info ziirave_wdt_info = {
420 .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING,
421 .identity = "RAVE Switch Watchdog",
422 };
423
424 static 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
ziirave_wdt_sysfs_show_firm(struct device * dev,struct device_attribute * attr,char * buf)433 static 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
454 static DEVICE_ATTR(firmware_version, S_IRUGO, ziirave_wdt_sysfs_show_firm,
455 NULL);
456
ziirave_wdt_sysfs_show_boot(struct device * dev,struct device_attribute * attr,char * buf)457 static 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
478 static DEVICE_ATTR(bootloader_version, S_IRUGO, ziirave_wdt_sysfs_show_boot,
479 NULL);
480
ziirave_wdt_sysfs_show_reason(struct device * dev,struct device_attribute * attr,char * buf)481 static 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
500 static DEVICE_ATTR(reset_reason, S_IRUGO, ziirave_wdt_sysfs_show_reason,
501 NULL);
502
ziirave_wdt_sysfs_store_firm(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)503 static 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
546 unlock_mutex:
547 mutex_unlock(&w_priv->sysfs_mutex);
548
549 release_firmware:
550 release_firmware(fw);
551
552 return err ? err : count;
553 }
554
555 static DEVICE_ATTR(update_firmware, S_IWUSR, NULL,
556 ziirave_wdt_sysfs_store_firm);
557
558 static 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 };
565 ATTRIBUTE_GROUPS(ziirave_wdt);
566
ziirave_wdt_init_duration(struct i2c_client * client)567 static 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
ziirave_wdt_probe(struct i2c_client * client)596 static 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
ziirave_wdt_remove(struct i2c_client * client)710 static 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
717 static const struct i2c_device_id ziirave_wdt_id[] = {
718 { "rave-wdt", 0 },
719 { }
720 };
721 MODULE_DEVICE_TABLE(i2c, ziirave_wdt_id);
722
723 static const struct of_device_id zrv_wdt_of_match[] = {
724 { .compatible = "zii,rave-wdt", },
725 { },
726 };
727 MODULE_DEVICE_TABLE(of, zrv_wdt_of_match);
728
729 static 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
739 module_i2c_driver(ziirave_wdt_driver);
740
741 MODULE_AUTHOR("Martyn Welch <martyn.welch@collabora.co.uk");
742 MODULE_DESCRIPTION("Zodiac Aerospace RAVE Switch Watchdog Processor Driver");
743 MODULE_LICENSE("GPL");
744