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
42 static int wdt_io;
43 static int cr_wdt_timeout; /* WDT timeout register */
44 static int cr_wdt_control; /* WDT control register */
45 static int cr_wdt_csr; /* WDT control & status register */
46 static int wdt_cfg_enter = 0x87;/* key to unlock configuration space */
47 static int wdt_cfg_leave = 0xAA;/* key to lock configuration space */
48
49 enum 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
54 static int timeout; /* in seconds */
55 module_param(timeout, int, 0);
56 MODULE_PARM_DESC(timeout,
57 "Watchdog timeout in seconds. 1 <= timeout <= 255, default="
58 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
59
60 static bool nowayout = WATCHDOG_NOWAYOUT;
61 module_param(nowayout, bool, 0);
62 MODULE_PARM_DESC(nowayout,
63 "Watchdog cannot be stopped once started (default="
64 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
65
66 static int early_disable;
67 module_param(early_disable, int, 0);
68 MODULE_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
superio_outb(int reg,int val)116 static void superio_outb(int reg, int val)
117 {
118 outb(reg, WDT_EFER);
119 outb(val, WDT_EFDR);
120 }
121
superio_inb(int reg)122 static inline int superio_inb(int reg)
123 {
124 outb(reg, WDT_EFER);
125 return inb(WDT_EFDR);
126 }
127
superio_enter(void)128 static int superio_enter(void)
129 {
130 if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
131 return -EBUSY;
132
133 outb_p(wdt_cfg_enter, WDT_EFER); /* Enter extended function mode */
134 outb_p(wdt_cfg_enter, WDT_EFER); /* Again according to manual */
135
136 return 0;
137 }
138
superio_select(int ld)139 static void superio_select(int ld)
140 {
141 superio_outb(0x07, ld);
142 }
143
superio_exit(void)144 static void superio_exit(void)
145 {
146 outb_p(wdt_cfg_leave, WDT_EFER); /* Leave extended function mode */
147 release_region(wdt_io, 2);
148 }
149
w83627hf_init(struct watchdog_device * wdog,enum chips chip)150 static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
151 {
152 int ret;
153 unsigned char t;
154
155 ret = superio_enter();
156 if (ret)
157 return ret;
158
159 superio_select(W83627HF_LD_WDT);
160
161 /* set CR30 bit 0 to activate GPIO2 */
162 t = superio_inb(0x30);
163 if (!(t & 0x01))
164 superio_outb(0x30, t | 0x01);
165
166 switch (chip) {
167 case w83627hf:
168 case w83627s:
169 t = superio_inb(0x2B) & ~0x10;
170 superio_outb(0x2B, t); /* set GPIO24 to WDT0 */
171 break;
172 case w83697hf:
173 /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
174 t = superio_inb(0x29) & ~0x60;
175 t |= 0x20;
176 superio_outb(0x29, t);
177 break;
178 case w83697ug:
179 /* Set pin 118 to WDTO# mode */
180 t = superio_inb(0x2b) & ~0x04;
181 superio_outb(0x2b, t);
182 break;
183 case w83627thf:
184 t = (superio_inb(0x2B) & ~0x08) | 0x04;
185 superio_outb(0x2B, t); /* set GPIO3 to WDT0 */
186 break;
187 case w83627dhg:
188 case w83627dhg_p:
189 t = superio_inb(0x2D) & ~0x01; /* PIN77 -> WDT0# */
190 superio_outb(0x2D, t); /* set GPIO5 to WDT0 */
191 t = superio_inb(cr_wdt_control);
192 t |= 0x02; /* enable the WDTO# output low pulse
193 * to the KBRST# pin */
194 superio_outb(cr_wdt_control, t);
195 break;
196 case w83637hf:
197 break;
198 case w83687thf:
199 t = superio_inb(0x2C) & ~0x80; /* PIN47 -> WDT0# */
200 superio_outb(0x2C, t);
201 break;
202 case w83627ehf:
203 case w83627uhg:
204 case w83667hg:
205 case w83667hg_b:
206 case nct6775:
207 case nct6776:
208 case nct6779:
209 case nct6791:
210 case nct6792:
211 case nct6793:
212 case nct6795:
213 case nct6796:
214 case nct6102:
215 case nct6116:
216 /*
217 * These chips have a fixed WDTO# output pin (W83627UHG),
218 * or support more than one WDTO# output pin.
219 * Don't touch its configuration, and hope the BIOS
220 * does the right thing.
221 */
222 t = superio_inb(cr_wdt_control);
223 t |= 0x02; /* enable the WDTO# output low pulse
224 * to the KBRST# pin */
225 superio_outb(cr_wdt_control, t);
226 break;
227 default:
228 break;
229 }
230
231 t = superio_inb(cr_wdt_timeout);
232 if (t != 0) {
233 if (early_disable) {
234 pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
235 superio_outb(cr_wdt_timeout, 0);
236 } else {
237 pr_info("Watchdog already running. Resetting timeout to %d sec\n",
238 wdog->timeout);
239 superio_outb(cr_wdt_timeout, wdog->timeout);
240 }
241 }
242
243 /* set second mode & disable keyboard turning off watchdog */
244 t = superio_inb(cr_wdt_control) & ~0x0C;
245 superio_outb(cr_wdt_control, t);
246
247 /* reset trigger, disable keyboard & mouse turning off watchdog */
248 t = superio_inb(cr_wdt_csr) & ~0xD0;
249 superio_outb(cr_wdt_csr, t);
250
251 superio_exit();
252
253 return 0;
254 }
255
wdt_set_time(unsigned int timeout)256 static int wdt_set_time(unsigned int timeout)
257 {
258 int ret;
259
260 ret = superio_enter();
261 if (ret)
262 return ret;
263
264 superio_select(W83627HF_LD_WDT);
265 superio_outb(cr_wdt_timeout, timeout);
266 superio_exit();
267
268 return 0;
269 }
270
wdt_start(struct watchdog_device * wdog)271 static int wdt_start(struct watchdog_device *wdog)
272 {
273 return wdt_set_time(wdog->timeout);
274 }
275
wdt_stop(struct watchdog_device * wdog)276 static int wdt_stop(struct watchdog_device *wdog)
277 {
278 return wdt_set_time(0);
279 }
280
wdt_set_timeout(struct watchdog_device * wdog,unsigned int timeout)281 static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
282 {
283 wdog->timeout = timeout;
284
285 return 0;
286 }
287
wdt_get_time(struct watchdog_device * wdog)288 static unsigned int wdt_get_time(struct watchdog_device *wdog)
289 {
290 unsigned int timeleft;
291 int ret;
292
293 ret = superio_enter();
294 if (ret)
295 return 0;
296
297 superio_select(W83627HF_LD_WDT);
298 timeleft = superio_inb(cr_wdt_timeout);
299 superio_exit();
300
301 return timeleft;
302 }
303
304 /*
305 * Kernel Interfaces
306 */
307
308 static const struct watchdog_info wdt_info = {
309 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
310 .identity = "W83627HF Watchdog",
311 };
312
313 static const struct watchdog_ops wdt_ops = {
314 .owner = THIS_MODULE,
315 .start = wdt_start,
316 .stop = wdt_stop,
317 .set_timeout = wdt_set_timeout,
318 .get_timeleft = wdt_get_time,
319 };
320
321 static struct watchdog_device wdt_dev = {
322 .info = &wdt_info,
323 .ops = &wdt_ops,
324 .timeout = WATCHDOG_TIMEOUT,
325 .min_timeout = 1,
326 .max_timeout = 255,
327 };
328
329 /*
330 * The WDT needs to learn about soft shutdowns in order to
331 * turn the timebomb registers off.
332 */
333
wdt_find(int addr)334 static int wdt_find(int addr)
335 {
336 u8 val;
337 int ret;
338
339 cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
340 cr_wdt_control = W83627HF_WDT_CONTROL;
341 cr_wdt_csr = W836X7HF_WDT_CSR;
342
343 ret = superio_enter();
344 if (ret)
345 return ret;
346 superio_select(W83627HF_LD_WDT);
347 val = superio_inb(0x20);
348 switch (val) {
349 case W83627HF_ID:
350 ret = w83627hf;
351 break;
352 case W83627S_ID:
353 ret = w83627s;
354 break;
355 case W83697HF_ID:
356 ret = w83697hf;
357 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
358 cr_wdt_control = W83697HF_WDT_CONTROL;
359 break;
360 case W83697UG_ID:
361 ret = w83697ug;
362 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
363 cr_wdt_control = W83697HF_WDT_CONTROL;
364 break;
365 case W83637HF_ID:
366 ret = w83637hf;
367 break;
368 case W83627THF_ID:
369 ret = w83627thf;
370 break;
371 case W83687THF_ID:
372 ret = w83687thf;
373 break;
374 case W83627EHF_ID:
375 ret = w83627ehf;
376 break;
377 case W83627DHG_ID:
378 ret = w83627dhg;
379 break;
380 case W83627DHG_P_ID:
381 ret = w83627dhg_p;
382 break;
383 case W83627UHG_ID:
384 ret = w83627uhg;
385 break;
386 case W83667HG_ID:
387 ret = w83667hg;
388 break;
389 case W83667HG_B_ID:
390 ret = w83667hg_b;
391 break;
392 case NCT6775_ID:
393 ret = nct6775;
394 break;
395 case NCT6776_ID:
396 ret = nct6776;
397 break;
398 case NCT6779_ID:
399 ret = nct6779;
400 break;
401 case NCT6791_ID:
402 ret = nct6791;
403 break;
404 case NCT6792_ID:
405 ret = nct6792;
406 break;
407 case NCT6793_ID:
408 ret = nct6793;
409 break;
410 case NCT6795_ID:
411 ret = nct6795;
412 break;
413 case NCT6796_ID:
414 ret = nct6796;
415 break;
416 case NCT6102_ID:
417 ret = nct6102;
418 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
419 cr_wdt_control = NCT6102D_WDT_CONTROL;
420 cr_wdt_csr = NCT6102D_WDT_CSR;
421 break;
422 case NCT6116_ID:
423 ret = nct6116;
424 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
425 cr_wdt_control = NCT6102D_WDT_CONTROL;
426 cr_wdt_csr = NCT6102D_WDT_CSR;
427 break;
428 case 0xff:
429 ret = -ENODEV;
430 break;
431 default:
432 ret = -ENODEV;
433 pr_err("Unsupported chip ID: 0x%02x\n", val);
434 break;
435 }
436 superio_exit();
437 return ret;
438 }
439
440 /*
441 * On some systems, the NCT6791D comes with a companion chip and the
442 * watchdog function is in this companion chip. We must use a different
443 * unlocking sequence to access the companion chip.
444 */
wdt_use_alt_key(const struct dmi_system_id * d)445 static int __init wdt_use_alt_key(const struct dmi_system_id *d)
446 {
447 wdt_cfg_enter = 0x88;
448 wdt_cfg_leave = 0xBB;
449
450 return 0;
451 }
452
453 static const struct dmi_system_id wdt_dmi_table[] __initconst = {
454 {
455 .matches = {
456 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "INVES"),
457 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "CTS"),
458 DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "INVES"),
459 DMI_EXACT_MATCH(DMI_BOARD_NAME, "SHARKBAY"),
460 },
461 .callback = wdt_use_alt_key,
462 },
463 {}
464 };
465
wdt_init(void)466 static int __init wdt_init(void)
467 {
468 int ret;
469 int chip;
470 static const char * const chip_name[] = {
471 "W83627HF",
472 "W83627S",
473 "W83697HF",
474 "W83697UG",
475 "W83637HF",
476 "W83627THF",
477 "W83687THF",
478 "W83627EHF",
479 "W83627DHG",
480 "W83627UHG",
481 "W83667HG",
482 "W83667DHG-P",
483 "W83667HG-B",
484 "NCT6775",
485 "NCT6776",
486 "NCT6779",
487 "NCT6791",
488 "NCT6792",
489 "NCT6793",
490 "NCT6795",
491 "NCT6796",
492 "NCT6102",
493 "NCT6116",
494 };
495
496 /* Apply system-specific quirks */
497 dmi_check_system(wdt_dmi_table);
498
499 wdt_io = 0x2e;
500 chip = wdt_find(0x2e);
501 if (chip < 0) {
502 wdt_io = 0x4e;
503 chip = wdt_find(0x4e);
504 if (chip < 0)
505 return chip;
506 }
507
508 pr_info("WDT driver for %s Super I/O chip initialising\n",
509 chip_name[chip]);
510
511 watchdog_init_timeout(&wdt_dev, timeout, NULL);
512 watchdog_set_nowayout(&wdt_dev, nowayout);
513 watchdog_stop_on_reboot(&wdt_dev);
514
515 ret = w83627hf_init(&wdt_dev, chip);
516 if (ret) {
517 pr_err("failed to initialize watchdog (err=%d)\n", ret);
518 return ret;
519 }
520
521 ret = watchdog_register_device(&wdt_dev);
522 if (ret)
523 return ret;
524
525 pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
526 wdt_dev.timeout, nowayout);
527
528 return ret;
529 }
530
wdt_exit(void)531 static void __exit wdt_exit(void)
532 {
533 watchdog_unregister_device(&wdt_dev);
534 }
535
536 module_init(wdt_init);
537 module_exit(wdt_exit);
538
539 MODULE_LICENSE("GPL");
540 MODULE_AUTHOR("Pádraig Brady <P@draigBrady.com>");
541 MODULE_DESCRIPTION("w83627hf/thf WDT driver");
542
