1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * w83627hf/thf WDT driver
4 *
5 * (c) Copyright 2013 Guenter Roeck
6 * converted to watchdog infrastructure
7 *
8 * (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
9 * added support for W83627THF.
10 *
11 * (c) Copyright 2003,2007 Pádraig Brady <P@draigBrady.com>
12 *
13 * Based on advantechwdt.c which is based on wdt.c.
14 * Original copyright messages:
15 *
16 * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
17 *
18 * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
19 * All Rights Reserved.
20 *
21 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
22 * warranty for any of this software. This material is provided
23 * "AS-IS" and at no charge.
24 *
25 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
26 */
27
28#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
29
30#include <linux/module.h>
31#include <linux/moduleparam.h>
32#include <linux/types.h>
33#include <linux/watchdog.h>
34#include <linux/ioport.h>
35#include <linux/init.h>
36#include <linux/io.h>
37#include <linux/dmi.h>
38
39#define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT"
40#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
41
42static int wdt_io;
43static int cr_wdt_timeout; /* WDT timeout register */
44static int cr_wdt_control; /* WDT control register */
45static int cr_wdt_csr; /* WDT control & status register */
46static int wdt_cfg_enter = 0x87;/* key to unlock configuration space */
47static int wdt_cfg_leave = 0xAA;/* key to lock configuration space */
48
49enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
50 w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg, w83627dhg_p,
51 w83667hg_b, nct6775, nct6776, nct6779, nct6791, nct6792, nct6793,
52 nct6795, nct6796, nct6102, nct6116 };
53
54static int timeout; /* in seconds */
55module_param(timeout, int, 0);
56MODULE_PARM_DESC(timeout,
57 "Watchdog timeout in seconds. 1 <= timeout <= 255, default="
58 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
59
60static bool nowayout = WATCHDOG_NOWAYOUT;
61module_param(nowayout, bool, 0);
62MODULE_PARM_DESC(nowayout,
63 "Watchdog cannot be stopped once started (default="
64 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
65
66static int early_disable;
67module_param(early_disable, int, 0);
68MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");
69
70/*
71 * Kernel methods.
72 */
73
74#define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */
75#define WDT_EFIR (wdt_io+0) /* Extended Function Index Register
76 (same as EFER) */
77#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
78
79#define W83627HF_LD_WDT 0x08
80
81#define W83627HF_ID 0x52
82#define W83627S_ID 0x59
83#define W83697HF_ID 0x60
84#define W83697UG_ID 0x68
85#define W83637HF_ID 0x70
86#define W83627THF_ID 0x82
87#define W83687THF_ID 0x85
88#define W83627EHF_ID 0x88
89#define W83627DHG_ID 0xa0
90#define W83627UHG_ID 0xa2
91#define W83667HG_ID 0xa5
92#define W83627DHG_P_ID 0xb0
93#define W83667HG_B_ID 0xb3
94#define NCT6775_ID 0xb4
95#define NCT6776_ID 0xc3
96#define NCT6102_ID 0xc4
97#define NCT6116_ID 0xd2
98#define NCT6779_ID 0xc5
99#define NCT6791_ID 0xc8
100#define NCT6792_ID 0xc9
101#define NCT6793_ID 0xd1
102#define NCT6795_ID 0xd3
103#define NCT6796_ID 0xd4 /* also NCT9697D, NCT9698D */
104
105#define W83627HF_WDT_TIMEOUT 0xf6
106#define W83697HF_WDT_TIMEOUT 0xf4
107#define NCT6102D_WDT_TIMEOUT 0xf1
108
109#define W83627HF_WDT_CONTROL 0xf5
110#define W83697HF_WDT_CONTROL 0xf3
111#define NCT6102D_WDT_CONTROL 0xf0
112
113#define W836X7HF_WDT_CSR 0xf7
114#define NCT6102D_WDT_CSR 0xf2
115
116#define WDT_CSR_STATUS 0x10
117#define WDT_CSR_KBD 0x40
118#define WDT_CSR_MOUSE 0x80
119
120static void superio_outb(int reg, int val)
121{
122 outb(value: reg, WDT_EFER);
123 outb(value: val, WDT_EFDR);
124}
125
126static inline int superio_inb(int reg)
127{
128 outb(value: reg, WDT_EFER);
129 return inb(WDT_EFDR);
130}
131
132static int superio_enter(void)
133{
134 if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
135 return -EBUSY;
136
137 outb_p(value: wdt_cfg_enter, WDT_EFER); /* Enter extended function mode */
138 outb_p(value: wdt_cfg_enter, WDT_EFER); /* Again according to manual */
139
140 return 0;
141}
142
143static void superio_select(int ld)
144{
145 superio_outb(reg: 0x07, val: ld);
146}
147
148static void superio_exit(void)
149{
150 outb_p(value: wdt_cfg_leave, WDT_EFER); /* Leave extended function mode */
151 release_region(wdt_io, 2);
152}
153
154static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
155{
156 int ret;
157 unsigned char t;
158
159 ret = superio_enter();
160 if (ret)
161 return ret;
162
163 superio_select(W83627HF_LD_WDT);
164
165 /* set CR30 bit 0 to activate GPIO2 */
166 t = superio_inb(reg: 0x30);
167 if (!(t & 0x01))
168 superio_outb(reg: 0x30, val: t | 0x01);
169
170 switch (chip) {
171 case w83627hf:
172 case w83627s:
173 t = superio_inb(reg: 0x2B) & ~0x10;
174 superio_outb(reg: 0x2B, val: t); /* set GPIO24 to WDT0 */
175 break;
176 case w83697hf:
177 /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
178 t = superio_inb(reg: 0x29) & ~0x60;
179 t |= 0x20;
180 superio_outb(reg: 0x29, val: t);
181 break;
182 case w83697ug:
183 /* Set pin 118 to WDTO# mode */
184 t = superio_inb(reg: 0x2b) & ~0x04;
185 superio_outb(reg: 0x2b, val: t);
186 break;
187 case w83627thf:
188 t = (superio_inb(reg: 0x2B) & ~0x08) | 0x04;
189 superio_outb(reg: 0x2B, val: t); /* set GPIO3 to WDT0 */
190 break;
191 case w83627dhg:
192 case w83627dhg_p:
193 t = superio_inb(reg: 0x2D) & ~0x01; /* PIN77 -> WDT0# */
194 superio_outb(reg: 0x2D, val: t); /* set GPIO5 to WDT0 */
195 t = superio_inb(reg: cr_wdt_control);
196 t |= 0x02; /* enable the WDTO# output low pulse
197 * to the KBRST# pin */
198 superio_outb(reg: cr_wdt_control, val: t);
199 break;
200 case w83637hf:
201 break;
202 case w83687thf:
203 t = superio_inb(reg: 0x2C) & ~0x80; /* PIN47 -> WDT0# */
204 superio_outb(reg: 0x2C, val: t);
205 break;
206 case w83627ehf:
207 case w83627uhg:
208 case w83667hg:
209 case w83667hg_b:
210 case nct6775:
211 case nct6776:
212 case nct6779:
213 case nct6791:
214 case nct6792:
215 case nct6793:
216 case nct6795:
217 case nct6796:
218 case nct6102:
219 case nct6116:
220 /*
221 * These chips have a fixed WDTO# output pin (W83627UHG),
222 * or support more than one WDTO# output pin.
223 * Don't touch its configuration, and hope the BIOS
224 * does the right thing.
225 */
226 t = superio_inb(reg: cr_wdt_control);
227 t |= 0x02; /* enable the WDTO# output low pulse
228 * to the KBRST# pin */
229 superio_outb(reg: cr_wdt_control, val: t);
230 break;
231 default:
232 break;
233 }
234
235 t = superio_inb(reg: cr_wdt_timeout);
236 if (t != 0) {
237 if (early_disable) {
238 pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
239 superio_outb(reg: cr_wdt_timeout, val: 0);
240 } else {
241 pr_info("Watchdog already running. Resetting timeout to %d sec\n",
242 wdog->timeout);
243 superio_outb(reg: cr_wdt_timeout, val: wdog->timeout);
244 }
245 }
246
247 /* set second mode & disable keyboard turning off watchdog */
248 t = superio_inb(reg: cr_wdt_control) & ~0x0C;
249 superio_outb(reg: cr_wdt_control, val: t);
250
251 t = superio_inb(reg: cr_wdt_csr);
252 if (t & WDT_CSR_STATUS)
253 wdog->bootstatus |= WDIOF_CARDRESET;
254
255 /* reset status, disable keyboard & mouse turning off watchdog */
256 t &= ~(WDT_CSR_STATUS | WDT_CSR_KBD | WDT_CSR_MOUSE);
257 superio_outb(reg: cr_wdt_csr, val: t);
258
259 superio_exit();
260
261 return 0;
262}
263
264static int wdt_set_time(unsigned int timeout)
265{
266 int ret;
267
268 ret = superio_enter();
269 if (ret)
270 return ret;
271
272 superio_select(W83627HF_LD_WDT);
273 superio_outb(reg: cr_wdt_timeout, val: timeout);
274 superio_exit();
275
276 return 0;
277}
278
279static int wdt_start(struct watchdog_device *wdog)
280{
281 return wdt_set_time(timeout: wdog->timeout);
282}
283
284static int wdt_stop(struct watchdog_device *wdog)
285{
286 return wdt_set_time(timeout: 0);
287}
288
289static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
290{
291 wdog->timeout = timeout;
292
293 return 0;
294}
295
296static unsigned int wdt_get_time(struct watchdog_device *wdog)
297{
298 unsigned int timeleft;
299 int ret;
300
301 ret = superio_enter();
302 if (ret)
303 return 0;
304
305 superio_select(W83627HF_LD_WDT);
306 timeleft = superio_inb(reg: cr_wdt_timeout);
307 superio_exit();
308
309 return timeleft;
310}
311
312/*
313 * Kernel Interfaces
314 */
315
316static const struct watchdog_info wdt_info = {
317 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
318 .identity = "W83627HF Watchdog",
319};
320
321static const struct watchdog_ops wdt_ops = {
322 .owner = THIS_MODULE,
323 .start = wdt_start,
324 .stop = wdt_stop,
325 .set_timeout = wdt_set_timeout,
326 .get_timeleft = wdt_get_time,
327};
328
329static struct watchdog_device wdt_dev = {
330 .info = &wdt_info,
331 .ops = &wdt_ops,
332 .timeout = WATCHDOG_TIMEOUT,
333 .min_timeout = 1,
334 .max_timeout = 255,
335};
336
337/*
338 * The WDT needs to learn about soft shutdowns in order to
339 * turn the timebomb registers off.
340 */
341
342static int wdt_find(int addr)
343{
344 u8 val;
345 int ret;
346
347 cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
348 cr_wdt_control = W83627HF_WDT_CONTROL;
349 cr_wdt_csr = W836X7HF_WDT_CSR;
350
351 ret = superio_enter();
352 if (ret)
353 return ret;
354 superio_select(W83627HF_LD_WDT);
355 val = superio_inb(reg: 0x20);
356 switch (val) {
357 case W83627HF_ID:
358 ret = w83627hf;
359 break;
360 case W83627S_ID:
361 ret = w83627s;
362 break;
363 case W83697HF_ID:
364 ret = w83697hf;
365 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
366 cr_wdt_control = W83697HF_WDT_CONTROL;
367 break;
368 case W83697UG_ID:
369 ret = w83697ug;
370 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
371 cr_wdt_control = W83697HF_WDT_CONTROL;
372 break;
373 case W83637HF_ID:
374 ret = w83637hf;
375 break;
376 case W83627THF_ID:
377 ret = w83627thf;
378 break;
379 case W83687THF_ID:
380 ret = w83687thf;
381 break;
382 case W83627EHF_ID:
383 ret = w83627ehf;
384 break;
385 case W83627DHG_ID:
386 ret = w83627dhg;
387 break;
388 case W83627DHG_P_ID:
389 ret = w83627dhg_p;
390 break;
391 case W83627UHG_ID:
392 ret = w83627uhg;
393 break;
394 case W83667HG_ID:
395 ret = w83667hg;
396 break;
397 case W83667HG_B_ID:
398 ret = w83667hg_b;
399 break;
400 case NCT6775_ID:
401 ret = nct6775;
402 break;
403 case NCT6776_ID:
404 ret = nct6776;
405 break;
406 case NCT6779_ID:
407 ret = nct6779;
408 break;
409 case NCT6791_ID:
410 ret = nct6791;
411 break;
412 case NCT6792_ID:
413 ret = nct6792;
414 break;
415 case NCT6793_ID:
416 ret = nct6793;
417 break;
418 case NCT6795_ID:
419 ret = nct6795;
420 break;
421 case NCT6796_ID:
422 ret = nct6796;
423 break;
424 case NCT6102_ID:
425 ret = nct6102;
426 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
427 cr_wdt_control = NCT6102D_WDT_CONTROL;
428 cr_wdt_csr = NCT6102D_WDT_CSR;
429 break;
430 case NCT6116_ID:
431 ret = nct6116;
432 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
433 cr_wdt_control = NCT6102D_WDT_CONTROL;
434 cr_wdt_csr = NCT6102D_WDT_CSR;
435 break;
436 case 0xff:
437 ret = -ENODEV;
438 break;
439 default:
440 ret = -ENODEV;
441 pr_err("Unsupported chip ID: 0x%02x\n", val);
442 break;
443 }
444 superio_exit();
445 return ret;
446}
447
448/*
449 * On some systems, the NCT6791D comes with a companion chip and the
450 * watchdog function is in this companion chip. We must use a different
451 * unlocking sequence to access the companion chip.
452 */
453static int __init wdt_use_alt_key(const struct dmi_system_id *d)
454{
455 wdt_cfg_enter = 0x88;
456 wdt_cfg_leave = 0xBB;
457
458 return 0;
459}
460
461static const struct dmi_system_id wdt_dmi_table[] __initconst = {
462 {
463 .matches = {
464 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "INVES"),
465 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "CTS"),
466 DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "INVES"),
467 DMI_EXACT_MATCH(DMI_BOARD_NAME, "SHARKBAY"),
468 },
469 .callback = wdt_use_alt_key,
470 },
471 {}
472};
473
474static int __init wdt_init(void)
475{
476 int ret;
477 int chip;
478 static const char * const chip_name[] = {
479 "W83627HF",
480 "W83627S",
481 "W83697HF",
482 "W83697UG",
483 "W83637HF",
484 "W83627THF",
485 "W83687THF",
486 "W83627EHF",
487 "W83627DHG",
488 "W83627UHG",
489 "W83667HG",
490 "W83667DHG-P",
491 "W83667HG-B",
492 "NCT6775",
493 "NCT6776",
494 "NCT6779",
495 "NCT6791",
496 "NCT6792",
497 "NCT6793",
498 "NCT6795",
499 "NCT6796",
500 "NCT6102",
501 "NCT6116",
502 };
503
504 /* Apply system-specific quirks */
505 dmi_check_system(list: wdt_dmi_table);
506
507 wdt_io = 0x2e;
508 chip = wdt_find(addr: 0x2e);
509 if (chip < 0) {
510 wdt_io = 0x4e;
511 chip = wdt_find(addr: 0x4e);
512 if (chip < 0)
513 return chip;
514 }
515
516 pr_info("WDT driver for %s Super I/O chip initialising\n",
517 chip_name[chip]);
518
519 watchdog_init_timeout(wdd: &wdt_dev, timeout_parm: timeout, NULL);
520 watchdog_set_nowayout(wdd: &wdt_dev, nowayout);
521 watchdog_stop_on_reboot(wdd: &wdt_dev);
522
523 ret = w83627hf_init(wdog: &wdt_dev, chip);
524 if (ret) {
525 pr_err("failed to initialize watchdog (err=%d)\n", ret);
526 return ret;
527 }
528
529 ret = watchdog_register_device(&wdt_dev);
530 if (ret)
531 return ret;
532
533 pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
534 wdt_dev.timeout, nowayout);
535
536 return ret;
537}
538
539static void __exit wdt_exit(void)
540{
541 watchdog_unregister_device(&wdt_dev);
542}
543
544module_init(wdt_init);
545module_exit(wdt_exit);
546
547MODULE_LICENSE("GPL");
548MODULE_AUTHOR("Pádraig Brady <P@draigBrady.com>");
549MODULE_DESCRIPTION("w83627hf/thf WDT driver");
550

source code of linux/drivers/watchdog/w83627hf_wdt.c