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 };
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 NCT6779_ID 0xc5
98 #define NCT6791_ID 0xc8
99 #define NCT6792_ID 0xc9
100 #define NCT6793_ID 0xd1
101 #define NCT6795_ID 0xd3
102 #define NCT6796_ID 0xd4 /* also NCT9697D, NCT9698D */
103
104 #define W83627HF_WDT_TIMEOUT 0xf6
105 #define W83697HF_WDT_TIMEOUT 0xf4
106 #define NCT6102D_WDT_TIMEOUT 0xf1
107
108 #define W83627HF_WDT_CONTROL 0xf5
109 #define W83697HF_WDT_CONTROL 0xf3
110 #define NCT6102D_WDT_CONTROL 0xf0
111
112 #define W836X7HF_WDT_CSR 0xf7
113 #define NCT6102D_WDT_CSR 0xf2
114
superio_outb(int reg,int val)115 static void superio_outb(int reg, int val)
116 {
117 outb(reg, WDT_EFER);
118 outb(val, WDT_EFDR);
119 }
120
superio_inb(int reg)121 static inline int superio_inb(int reg)
122 {
123 outb(reg, WDT_EFER);
124 return inb(WDT_EFDR);
125 }
126
superio_enter(void)127 static int superio_enter(void)
128 {
129 if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
130 return -EBUSY;
131
132 outb_p(wdt_cfg_enter, WDT_EFER); /* Enter extended function mode */
133 outb_p(wdt_cfg_enter, WDT_EFER); /* Again according to manual */
134
135 return 0;
136 }
137
superio_select(int ld)138 static void superio_select(int ld)
139 {
140 superio_outb(0x07, ld);
141 }
142
superio_exit(void)143 static void superio_exit(void)
144 {
145 outb_p(wdt_cfg_leave, WDT_EFER); /* Leave extended function mode */
146 release_region(wdt_io, 2);
147 }
148
w83627hf_init(struct watchdog_device * wdog,enum chips chip)149 static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
150 {
151 int ret;
152 unsigned char t;
153
154 ret = superio_enter();
155 if (ret)
156 return ret;
157
158 superio_select(W83627HF_LD_WDT);
159
160 /* set CR30 bit 0 to activate GPIO2 */
161 t = superio_inb(0x30);
162 if (!(t & 0x01))
163 superio_outb(0x30, t | 0x01);
164
165 switch (chip) {
166 case w83627hf:
167 case w83627s:
168 t = superio_inb(0x2B) & ~0x10;
169 superio_outb(0x2B, t); /* set GPIO24 to WDT0 */
170 break;
171 case w83697hf:
172 /* Set pin 119 to WDTO# mode (= CR29, WDT0) */
173 t = superio_inb(0x29) & ~0x60;
174 t |= 0x20;
175 superio_outb(0x29, t);
176 break;
177 case w83697ug:
178 /* Set pin 118 to WDTO# mode */
179 t = superio_inb(0x2b) & ~0x04;
180 superio_outb(0x2b, t);
181 break;
182 case w83627thf:
183 t = (superio_inb(0x2B) & ~0x08) | 0x04;
184 superio_outb(0x2B, t); /* set GPIO3 to WDT0 */
185 break;
186 case w83627dhg:
187 case w83627dhg_p:
188 t = superio_inb(0x2D) & ~0x01; /* PIN77 -> WDT0# */
189 superio_outb(0x2D, t); /* set GPIO5 to WDT0 */
190 t = superio_inb(cr_wdt_control);
191 t |= 0x02; /* enable the WDTO# output low pulse
192 * to the KBRST# pin */
193 superio_outb(cr_wdt_control, t);
194 break;
195 case w83637hf:
196 break;
197 case w83687thf:
198 t = superio_inb(0x2C) & ~0x80; /* PIN47 -> WDT0# */
199 superio_outb(0x2C, t);
200 break;
201 case w83627ehf:
202 case w83627uhg:
203 case w83667hg:
204 case w83667hg_b:
205 case nct6775:
206 case nct6776:
207 case nct6779:
208 case nct6791:
209 case nct6792:
210 case nct6793:
211 case nct6795:
212 case nct6796:
213 case nct6102:
214 /*
215 * These chips have a fixed WDTO# output pin (W83627UHG),
216 * or support more than one WDTO# output pin.
217 * Don't touch its configuration, and hope the BIOS
218 * does the right thing.
219 */
220 t = superio_inb(cr_wdt_control);
221 t |= 0x02; /* enable the WDTO# output low pulse
222 * to the KBRST# pin */
223 superio_outb(cr_wdt_control, t);
224 break;
225 default:
226 break;
227 }
228
229 t = superio_inb(cr_wdt_timeout);
230 if (t != 0) {
231 if (early_disable) {
232 pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
233 superio_outb(cr_wdt_timeout, 0);
234 } else {
235 pr_info("Watchdog already running. Resetting timeout to %d sec\n",
236 wdog->timeout);
237 superio_outb(cr_wdt_timeout, wdog->timeout);
238 }
239 }
240
241 /* set second mode & disable keyboard turning off watchdog */
242 t = superio_inb(cr_wdt_control) & ~0x0C;
243 superio_outb(cr_wdt_control, t);
244
245 /* reset trigger, disable keyboard & mouse turning off watchdog */
246 t = superio_inb(cr_wdt_csr) & ~0xD0;
247 superio_outb(cr_wdt_csr, t);
248
249 superio_exit();
250
251 return 0;
252 }
253
wdt_set_time(unsigned int timeout)254 static int wdt_set_time(unsigned int timeout)
255 {
256 int ret;
257
258 ret = superio_enter();
259 if (ret)
260 return ret;
261
262 superio_select(W83627HF_LD_WDT);
263 superio_outb(cr_wdt_timeout, timeout);
264 superio_exit();
265
266 return 0;
267 }
268
wdt_start(struct watchdog_device * wdog)269 static int wdt_start(struct watchdog_device *wdog)
270 {
271 return wdt_set_time(wdog->timeout);
272 }
273
wdt_stop(struct watchdog_device * wdog)274 static int wdt_stop(struct watchdog_device *wdog)
275 {
276 return wdt_set_time(0);
277 }
278
wdt_set_timeout(struct watchdog_device * wdog,unsigned int timeout)279 static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
280 {
281 wdog->timeout = timeout;
282
283 return 0;
284 }
285
wdt_get_time(struct watchdog_device * wdog)286 static unsigned int wdt_get_time(struct watchdog_device *wdog)
287 {
288 unsigned int timeleft;
289 int ret;
290
291 ret = superio_enter();
292 if (ret)
293 return 0;
294
295 superio_select(W83627HF_LD_WDT);
296 timeleft = superio_inb(cr_wdt_timeout);
297 superio_exit();
298
299 return timeleft;
300 }
301
302 /*
303 * Kernel Interfaces
304 */
305
306 static const struct watchdog_info wdt_info = {
307 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
308 .identity = "W83627HF Watchdog",
309 };
310
311 static const struct watchdog_ops wdt_ops = {
312 .owner = THIS_MODULE,
313 .start = wdt_start,
314 .stop = wdt_stop,
315 .set_timeout = wdt_set_timeout,
316 .get_timeleft = wdt_get_time,
317 };
318
319 static struct watchdog_device wdt_dev = {
320 .info = &wdt_info,
321 .ops = &wdt_ops,
322 .timeout = WATCHDOG_TIMEOUT,
323 .min_timeout = 1,
324 .max_timeout = 255,
325 };
326
327 /*
328 * The WDT needs to learn about soft shutdowns in order to
329 * turn the timebomb registers off.
330 */
331
wdt_find(int addr)332 static int wdt_find(int addr)
333 {
334 u8 val;
335 int ret;
336
337 cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
338 cr_wdt_control = W83627HF_WDT_CONTROL;
339 cr_wdt_csr = W836X7HF_WDT_CSR;
340
341 ret = superio_enter();
342 if (ret)
343 return ret;
344 superio_select(W83627HF_LD_WDT);
345 val = superio_inb(0x20);
346 switch (val) {
347 case W83627HF_ID:
348 ret = w83627hf;
349 break;
350 case W83627S_ID:
351 ret = w83627s;
352 break;
353 case W83697HF_ID:
354 ret = w83697hf;
355 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
356 cr_wdt_control = W83697HF_WDT_CONTROL;
357 break;
358 case W83697UG_ID:
359 ret = w83697ug;
360 cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
361 cr_wdt_control = W83697HF_WDT_CONTROL;
362 break;
363 case W83637HF_ID:
364 ret = w83637hf;
365 break;
366 case W83627THF_ID:
367 ret = w83627thf;
368 break;
369 case W83687THF_ID:
370 ret = w83687thf;
371 break;
372 case W83627EHF_ID:
373 ret = w83627ehf;
374 break;
375 case W83627DHG_ID:
376 ret = w83627dhg;
377 break;
378 case W83627DHG_P_ID:
379 ret = w83627dhg_p;
380 break;
381 case W83627UHG_ID:
382 ret = w83627uhg;
383 break;
384 case W83667HG_ID:
385 ret = w83667hg;
386 break;
387 case W83667HG_B_ID:
388 ret = w83667hg_b;
389 break;
390 case NCT6775_ID:
391 ret = nct6775;
392 break;
393 case NCT6776_ID:
394 ret = nct6776;
395 break;
396 case NCT6779_ID:
397 ret = nct6779;
398 break;
399 case NCT6791_ID:
400 ret = nct6791;
401 break;
402 case NCT6792_ID:
403 ret = nct6792;
404 break;
405 case NCT6793_ID:
406 ret = nct6793;
407 break;
408 case NCT6795_ID:
409 ret = nct6795;
410 break;
411 case NCT6796_ID:
412 ret = nct6796;
413 break;
414 case NCT6102_ID:
415 ret = nct6102;
416 cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
417 cr_wdt_control = NCT6102D_WDT_CONTROL;
418 cr_wdt_csr = NCT6102D_WDT_CSR;
419 break;
420 case 0xff:
421 ret = -ENODEV;
422 break;
423 default:
424 ret = -ENODEV;
425 pr_err("Unsupported chip ID: 0x%02x\n", val);
426 break;
427 }
428 superio_exit();
429 return ret;
430 }
431
432 /*
433 * On some systems, the NCT6791D comes with a companion chip and the
434 * watchdog function is in this companion chip. We must use a different
435 * unlocking sequence to access the companion chip.
436 */
wdt_use_alt_key(const struct dmi_system_id * d)437 static int __init wdt_use_alt_key(const struct dmi_system_id *d)
438 {
439 wdt_cfg_enter = 0x88;
440 wdt_cfg_leave = 0xBB;
441
442 return 0;
443 }
444
445 static const struct dmi_system_id wdt_dmi_table[] __initconst = {
446 {
447 .matches = {
448 DMI_EXACT_MATCH(DMI_SYS_VENDOR, "INVES"),
449 DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "CTS"),
450 DMI_EXACT_MATCH(DMI_BOARD_VENDOR, "INVES"),
451 DMI_EXACT_MATCH(DMI_BOARD_NAME, "SHARKBAY"),
452 },
453 .callback = wdt_use_alt_key,
454 },
455 {}
456 };
457
wdt_init(void)458 static int __init wdt_init(void)
459 {
460 int ret;
461 int chip;
462 static const char * const chip_name[] = {
463 "W83627HF",
464 "W83627S",
465 "W83697HF",
466 "W83697UG",
467 "W83637HF",
468 "W83627THF",
469 "W83687THF",
470 "W83627EHF",
471 "W83627DHG",
472 "W83627UHG",
473 "W83667HG",
474 "W83667DHG-P",
475 "W83667HG-B",
476 "NCT6775",
477 "NCT6776",
478 "NCT6779",
479 "NCT6791",
480 "NCT6792",
481 "NCT6793",
482 "NCT6795",
483 "NCT6796",
484 "NCT6102",
485 };
486
487 /* Apply system-specific quirks */
488 dmi_check_system(wdt_dmi_table);
489
490 wdt_io = 0x2e;
491 chip = wdt_find(0x2e);
492 if (chip < 0) {
493 wdt_io = 0x4e;
494 chip = wdt_find(0x4e);
495 if (chip < 0)
496 return chip;
497 }
498
499 pr_info("WDT driver for %s Super I/O chip initialising\n",
500 chip_name[chip]);
501
502 watchdog_init_timeout(&wdt_dev, timeout, NULL);
503 watchdog_set_nowayout(&wdt_dev, nowayout);
504 watchdog_stop_on_reboot(&wdt_dev);
505
506 ret = w83627hf_init(&wdt_dev, chip);
507 if (ret) {
508 pr_err("failed to initialize watchdog (err=%d)\n", ret);
509 return ret;
510 }
511
512 ret = watchdog_register_device(&wdt_dev);
513 if (ret)
514 return ret;
515
516 pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
517 wdt_dev.timeout, nowayout);
518
519 return ret;
520 }
521
wdt_exit(void)522 static void __exit wdt_exit(void)
523 {
524 watchdog_unregister_device(&wdt_dev);
525 }
526
527 module_init(wdt_init);
528 module_exit(wdt_exit);
529
530 MODULE_LICENSE("GPL");
531 MODULE_AUTHOR("Pádraig Brady <P@draigBrady.com>");
532 MODULE_DESCRIPTION("w83627hf/thf WDT driver");
533
