summaryrefslogtreecommitdiff
path: root/drivers/watchdog/w83627hf_wdt.c
blob: ef2ecaf53a147e54ca96c862b43e4c87e59903b6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
/*
 *	w83627hf/thf WDT driver
 *
 *	(c) Copyright 2013 Guenter Roeck
 *		converted to watchdog infrastructure
 *
 *	(c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
 *		added support for W83627THF.
 *
 *	(c) Copyright 2003,2007 Pádraig Brady <P@draigBrady.com>
 *
 *	Based on advantechwdt.c which is based on wdt.c.
 *	Original copyright messages:
 *
 *	(c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
 *
 *	(c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
 *						All Rights Reserved.
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 *
 *	Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
 *	warranty for any of this software. This material is provided
 *	"AS-IS" and at no charge.
 *
 *	(c) Copyright 1995    Alan Cox <alan@lxorguk.ukuu.org.uk>
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/watchdog.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/io.h>

#define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT"
#define WATCHDOG_TIMEOUT 60		/* 60 sec default timeout */

static int wdt_io;
static int cr_wdt_timeout;	/* WDT timeout register */
static int cr_wdt_control;	/* WDT control register */
static int cr_wdt_csr;		/* WDT control & status register */

enum chips { w83627hf, w83627s, w83697hf, w83697ug, w83637hf, w83627thf,
	     w83687thf, w83627ehf, w83627dhg, w83627uhg, w83667hg, w83627dhg_p,
	     w83667hg_b, nct6775, nct6776, nct6779, nct6791, nct6792, nct6102 };

static int timeout;			/* in seconds */
module_param(timeout, int, 0);
MODULE_PARM_DESC(timeout,
		"Watchdog timeout in seconds. 1 <= timeout <= 255, default="
				__MODULE_STRING(WATCHDOG_TIMEOUT) ".");

static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
		"Watchdog cannot be stopped once started (default="
				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

static int early_disable;
module_param(early_disable, int, 0);
MODULE_PARM_DESC(early_disable, "Disable watchdog at boot time (default=0)");

/*
 *	Kernel methods.
 */

#define WDT_EFER (wdt_io+0)   /* Extended Function Enable Registers */
#define WDT_EFIR (wdt_io+0)   /* Extended Function Index Register
							(same as EFER) */
#define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */

#define W83627HF_LD_WDT		0x08

#define W83627HF_ID		0x52
#define W83627S_ID		0x59
#define W83697HF_ID		0x60
#define W83697UG_ID		0x68
#define W83637HF_ID		0x70
#define W83627THF_ID		0x82
#define W83687THF_ID		0x85
#define W83627EHF_ID		0x88
#define W83627DHG_ID		0xa0
#define W83627UHG_ID		0xa2
#define W83667HG_ID		0xa5
#define W83627DHG_P_ID		0xb0
#define W83667HG_B_ID		0xb3
#define NCT6775_ID		0xb4
#define NCT6776_ID		0xc3
#define NCT6102_ID		0xc4
#define NCT6779_ID		0xc5
#define NCT6791_ID		0xc8
#define NCT6792_ID		0xc9

#define W83627HF_WDT_TIMEOUT	0xf6
#define W83697HF_WDT_TIMEOUT	0xf4
#define NCT6102D_WDT_TIMEOUT	0xf1

#define W83627HF_WDT_CONTROL	0xf5
#define W83697HF_WDT_CONTROL	0xf3
#define NCT6102D_WDT_CONTROL	0xf0

#define W836X7HF_WDT_CSR	0xf7
#define NCT6102D_WDT_CSR	0xf2

static void superio_outb(int reg, int val)
{
	outb(reg, WDT_EFER);
	outb(val, WDT_EFDR);
}

static inline int superio_inb(int reg)
{
	outb(reg, WDT_EFER);
	return inb(WDT_EFDR);
}

static int superio_enter(void)
{
	if (!request_muxed_region(wdt_io, 2, WATCHDOG_NAME))
		return -EBUSY;

	outb_p(0x87, WDT_EFER); /* Enter extended function mode */
	outb_p(0x87, WDT_EFER); /* Again according to manual */

	return 0;
}

static void superio_select(int ld)
{
	superio_outb(0x07, ld);
}

static void superio_exit(void)
{
	outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
	release_region(wdt_io, 2);
}

static int w83627hf_init(struct watchdog_device *wdog, enum chips chip)
{
	int ret;
	unsigned char t;

	ret = superio_enter();
	if (ret)
		return ret;

	superio_select(W83627HF_LD_WDT);

	/* set CR30 bit 0 to activate GPIO2 */
	t = superio_inb(0x30);
	if (!(t & 0x01))
		superio_outb(0x30, t | 0x01);

	switch (chip) {
	case w83627hf:
	case w83627s:
		t = superio_inb(0x2B) & ~0x10;
		superio_outb(0x2B, t); /* set GPIO24 to WDT0 */
		break;
	case w83697hf:
		/* Set pin 119 to WDTO# mode (= CR29, WDT0) */
		t = superio_inb(0x29) & ~0x60;
		t |= 0x20;
		superio_outb(0x29, t);
		break;
	case w83697ug:
		/* Set pin 118 to WDTO# mode */
		t = superio_inb(0x2b) & ~0x04;
		superio_outb(0x2b, t);
		break;
	case w83627thf:
		t = (superio_inb(0x2B) & ~0x08) | 0x04;
		superio_outb(0x2B, t); /* set GPIO3 to WDT0 */
		break;
	case w83627dhg:
	case w83627dhg_p:
		t = superio_inb(0x2D) & ~0x01; /* PIN77 -> WDT0# */
		superio_outb(0x2D, t); /* set GPIO5 to WDT0 */
		t = superio_inb(cr_wdt_control);
		t |= 0x02;	/* enable the WDTO# output low pulse
				 * to the KBRST# pin */
		superio_outb(cr_wdt_control, t);
		break;
	case w83637hf:
		break;
	case w83687thf:
		t = superio_inb(0x2C) & ~0x80; /* PIN47 -> WDT0# */
		superio_outb(0x2C, t);
		break;
	case w83627ehf:
	case w83627uhg:
	case w83667hg:
	case w83667hg_b:
	case nct6775:
	case nct6776:
	case nct6779:
	case nct6791:
	case nct6792:
	case nct6102:
		/*
		 * These chips have a fixed WDTO# output pin (W83627UHG),
		 * or support more than one WDTO# output pin.
		 * Don't touch its configuration, and hope the BIOS
		 * does the right thing.
		 */
		t = superio_inb(cr_wdt_control);
		t |= 0x02;	/* enable the WDTO# output low pulse
				 * to the KBRST# pin */
		superio_outb(cr_wdt_control, t);
		break;
	default:
		break;
	}

	t = superio_inb(cr_wdt_timeout);
	if (t != 0) {
		if (early_disable) {
			pr_warn("Stopping previously enabled watchdog until userland kicks in\n");
			superio_outb(cr_wdt_timeout, 0);
		} else {
			pr_info("Watchdog already running. Resetting timeout to %d sec\n",
				wdog->timeout);
			superio_outb(cr_wdt_timeout, wdog->timeout);
		}
	}

	/* set second mode & disable keyboard turning off watchdog */
	t = superio_inb(cr_wdt_control) & ~0x0C;
	superio_outb(cr_wdt_control, t);

	/* reset trigger, disable keyboard & mouse turning off watchdog */
	t = superio_inb(cr_wdt_csr) & ~0xD0;
	superio_outb(cr_wdt_csr, t);

	superio_exit();

	return 0;
}

static int wdt_set_time(unsigned int timeout)
{
	int ret;

	ret = superio_enter();
	if (ret)
		return ret;

	superio_select(W83627HF_LD_WDT);
	superio_outb(cr_wdt_timeout, timeout);
	superio_exit();

	return 0;
}

static int wdt_start(struct watchdog_device *wdog)
{
	return wdt_set_time(wdog->timeout);
}

static int wdt_stop(struct watchdog_device *wdog)
{
	return wdt_set_time(0);
}

static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
{
	wdog->timeout = timeout;

	return 0;
}

static unsigned int wdt_get_time(struct watchdog_device *wdog)
{
	unsigned int timeleft;
	int ret;

	ret = superio_enter();
	if (ret)
		return 0;

	superio_select(W83627HF_LD_WDT);
	timeleft = superio_inb(cr_wdt_timeout);
	superio_exit();

	return timeleft;
}

/*
 *	Kernel Interfaces
 */

static struct watchdog_info wdt_info = {
	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
	.identity = "W83627HF Watchdog",
};

static const struct watchdog_ops wdt_ops = {
	.owner = THIS_MODULE,
	.start = wdt_start,
	.stop = wdt_stop,
	.set_timeout = wdt_set_timeout,
	.get_timeleft = wdt_get_time,
};

static struct watchdog_device wdt_dev = {
	.info = &wdt_info,
	.ops = &wdt_ops,
	.timeout = WATCHDOG_TIMEOUT,
	.min_timeout = 1,
	.max_timeout = 255,
};

/*
 *	The WDT needs to learn about soft shutdowns in order to
 *	turn the timebomb registers off.
 */

static int wdt_find(int addr)
{
	u8 val;
	int ret;

	cr_wdt_timeout = W83627HF_WDT_TIMEOUT;
	cr_wdt_control = W83627HF_WDT_CONTROL;
	cr_wdt_csr = W836X7HF_WDT_CSR;

	ret = superio_enter();
	if (ret)
		return ret;
	superio_select(W83627HF_LD_WDT);
	val = superio_inb(0x20);
	switch (val) {
	case W83627HF_ID:
		ret = w83627hf;
		break;
	case W83627S_ID:
		ret = w83627s;
		break;
	case W83697HF_ID:
		ret = w83697hf;
		cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
		cr_wdt_control = W83697HF_WDT_CONTROL;
		break;
	case W83697UG_ID:
		ret = w83697ug;
		cr_wdt_timeout = W83697HF_WDT_TIMEOUT;
		cr_wdt_control = W83697HF_WDT_CONTROL;
		break;
	case W83637HF_ID:
		ret = w83637hf;
		break;
	case W83627THF_ID:
		ret = w83627thf;
		break;
	case W83687THF_ID:
		ret = w83687thf;
		break;
	case W83627EHF_ID:
		ret = w83627ehf;
		break;
	case W83627DHG_ID:
		ret = w83627dhg;
		break;
	case W83627DHG_P_ID:
		ret = w83627dhg_p;
		break;
	case W83627UHG_ID:
		ret = w83627uhg;
		break;
	case W83667HG_ID:
		ret = w83667hg;
		break;
	case W83667HG_B_ID:
		ret = w83667hg_b;
		break;
	case NCT6775_ID:
		ret = nct6775;
		break;
	case NCT6776_ID:
		ret = nct6776;
		break;
	case NCT6779_ID:
		ret = nct6779;
		break;
	case NCT6791_ID:
		ret = nct6791;
		break;
	case NCT6792_ID:
		ret = nct6792;
		break;
	case NCT6102_ID:
		ret = nct6102;
		cr_wdt_timeout = NCT6102D_WDT_TIMEOUT;
		cr_wdt_control = NCT6102D_WDT_CONTROL;
		cr_wdt_csr = NCT6102D_WDT_CSR;
		break;
	case 0xff:
		ret = -ENODEV;
		break;
	default:
		ret = -ENODEV;
		pr_err("Unsupported chip ID: 0x%02x\n", val);
		break;
	}
	superio_exit();
	return ret;
}

static int __init wdt_init(void)
{
	int ret;
	int chip;
	const char * const chip_name[] = {
		"W83627HF",
		"W83627S",
		"W83697HF",
		"W83697UG",
		"W83637HF",
		"W83627THF",
		"W83687THF",
		"W83627EHF",
		"W83627DHG",
		"W83627UHG",
		"W83667HG",
		"W83667DHG-P",
		"W83667HG-B",
		"NCT6775",
		"NCT6776",
		"NCT6779",
		"NCT6791",
		"NCT6792",
		"NCT6102",
	};

	wdt_io = 0x2e;
	chip = wdt_find(0x2e);
	if (chip < 0) {
		wdt_io = 0x4e;
		chip = wdt_find(0x4e);
		if (chip < 0)
			return chip;
	}

	pr_info("WDT driver for %s Super I/O chip initialising\n",
		chip_name[chip]);

	watchdog_init_timeout(&wdt_dev, timeout, NULL);
	watchdog_set_nowayout(&wdt_dev, nowayout);
	watchdog_stop_on_reboot(&wdt_dev);

	ret = w83627hf_init(&wdt_dev, chip);
	if (ret) {
		pr_err("failed to initialize watchdog (err=%d)\n", ret);
		return ret;
	}

	ret = watchdog_register_device(&wdt_dev);
	if (ret)
		return ret;

	pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
		wdt_dev.timeout, nowayout);

	return ret;
}

static void __exit wdt_exit(void)
{
	watchdog_unregister_device(&wdt_dev);
}

module_init(wdt_init);
module_exit(wdt_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Pádraig  Brady <P@draigBrady.com>");
MODULE_DESCRIPTION("w83627hf/thf WDT driver");