1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /***************************************************************************
3 * Copyright (C) 2006 by Hans Edgington <hans@edgington.nl> *
4 * Copyright (C) 2007-2009 Hans de Goede <hdegoede@redhat.com> *
5 * Copyright (C) 2010 Giel van Schijndel <me@mortis.eu> *
6 * *
7 ***************************************************************************/
8
9 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
10
11 #include <linux/err.h>
12 #include <linux/fs.h>
13 #include <linux/init.h>
14 #include <linux/io.h>
15 #include <linux/ioport.h>
16 #include <linux/miscdevice.h>
17 #include <linux/module.h>
18 #include <linux/mutex.h>
19 #include <linux/notifier.h>
20 #include <linux/reboot.h>
21 #include <linux/uaccess.h>
22 #include <linux/watchdog.h>
23
24 #define DRVNAME "f71808e_wdt"
25
26 #define SIO_F71808FG_LD_WDT 0x07 /* Watchdog timer logical device */
27 #define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */
28 #define SIO_LOCK_KEY 0xAA /* Key to disable Super-I/O */
29
30 #define SIO_REG_LDSEL 0x07 /* Logical device select */
31 #define SIO_REG_DEVID 0x20 /* Device ID (2 bytes) */
32 #define SIO_REG_DEVREV 0x22 /* Device revision */
33 #define SIO_REG_MANID 0x23 /* Fintek ID (2 bytes) */
34 #define SIO_REG_CLOCK_SEL 0x26 /* Clock select */
35 #define SIO_REG_ROM_ADDR_SEL 0x27 /* ROM address select */
36 #define SIO_F81866_REG_PORT_SEL 0x27 /* F81866 Multi-Function Register */
37 #define SIO_REG_TSI_LEVEL_SEL 0x28 /* TSI Level select */
38 #define SIO_REG_MFUNCT1 0x29 /* Multi function select 1 */
39 #define SIO_REG_MFUNCT2 0x2a /* Multi function select 2 */
40 #define SIO_REG_MFUNCT3 0x2b /* Multi function select 3 */
41 #define SIO_F81866_REG_GPIO1 0x2c /* F81866 GPIO1 Enable Register */
42 #define SIO_REG_ENABLE 0x30 /* Logical device enable */
43 #define SIO_REG_ADDR 0x60 /* Logical device address (2 bytes) */
44
45 #define SIO_FINTEK_ID 0x1934 /* Manufacturers ID */
46 #define SIO_F71808_ID 0x0901 /* Chipset ID */
47 #define SIO_F71858_ID 0x0507 /* Chipset ID */
48 #define SIO_F71862_ID 0x0601 /* Chipset ID */
49 #define SIO_F71868_ID 0x1106 /* Chipset ID */
50 #define SIO_F71869_ID 0x0814 /* Chipset ID */
51 #define SIO_F71869A_ID 0x1007 /* Chipset ID */
52 #define SIO_F71882_ID 0x0541 /* Chipset ID */
53 #define SIO_F71889_ID 0x0723 /* Chipset ID */
54 #define SIO_F81803_ID 0x1210 /* Chipset ID */
55 #define SIO_F81865_ID 0x0704 /* Chipset ID */
56 #define SIO_F81866_ID 0x1010 /* Chipset ID */
57
58 #define F71808FG_REG_WDO_CONF 0xf0
59 #define F71808FG_REG_WDT_CONF 0xf5
60 #define F71808FG_REG_WD_TIME 0xf6
61
62 #define F71808FG_FLAG_WDOUT_EN 7
63
64 #define F71808FG_FLAG_WDTMOUT_STS 6
65 #define F71808FG_FLAG_WD_EN 5
66 #define F71808FG_FLAG_WD_PULSE 4
67 #define F71808FG_FLAG_WD_UNIT 3
68
69 #define F81865_REG_WDO_CONF 0xfa
70 #define F81865_FLAG_WDOUT_EN 0
71
72 /* Default values */
73 #define WATCHDOG_TIMEOUT 60 /* 1 minute default timeout */
74 #define WATCHDOG_MAX_TIMEOUT (60 * 255)
75 #define WATCHDOG_PULSE_WIDTH 125 /* 125 ms, default pulse width for
76 watchdog signal */
77 #define WATCHDOG_F71862FG_PIN 63 /* default watchdog reset output
78 pin number 63 */
79
80 static unsigned short force_id;
81 module_param(force_id, ushort, 0);
82 MODULE_PARM_DESC(force_id, "Override the detected device ID");
83
84 static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
85 static int timeout = WATCHDOG_TIMEOUT; /* default timeout in seconds */
86 module_param(timeout, int, 0);
87 MODULE_PARM_DESC(timeout,
88 "Watchdog timeout in seconds. 1<= timeout <="
89 __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
90 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
91
92 static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
93 module_param(pulse_width, uint, 0);
94 MODULE_PARM_DESC(pulse_width,
95 "Watchdog signal pulse width. 0(=level), 1, 25, 30, 125, 150, 5000 or 6000 ms"
96 " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
97
98 static unsigned int f71862fg_pin = WATCHDOG_F71862FG_PIN;
99 module_param(f71862fg_pin, uint, 0);
100 MODULE_PARM_DESC(f71862fg_pin,
101 "Watchdog f71862fg reset output pin configuration. Choose pin 56 or 63"
102 " (default=" __MODULE_STRING(WATCHDOG_F71862FG_PIN)")");
103
104 static bool nowayout = WATCHDOG_NOWAYOUT;
105 module_param(nowayout, bool, 0444);
106 MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
107
108 static unsigned int start_withtimeout;
109 module_param(start_withtimeout, uint, 0);
110 MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
111 " given initial timeout. Zero (default) disables this feature.");
112
113 enum chips { f71808fg, f71858fg, f71862fg, f71868, f71869, f71882fg, f71889fg,
114 f81803, f81865, f81866};
115
116 static const char *f71808e_names[] = {
117 "f71808fg",
118 "f71858fg",
119 "f71862fg",
120 "f71868",
121 "f71869",
122 "f71882fg",
123 "f71889fg",
124 "f81803",
125 "f81865",
126 "f81866",
127 };
128
129 /* Super-I/O Function prototypes */
130 static inline int superio_inb(int base, int reg);
131 static inline int superio_inw(int base, int reg);
132 static inline void superio_outb(int base, int reg, u8 val);
133 static inline void superio_set_bit(int base, int reg, int bit);
134 static inline void superio_clear_bit(int base, int reg, int bit);
135 static inline int superio_enter(int base);
136 static inline void superio_select(int base, int ld);
137 static inline void superio_exit(int base);
138
139 struct watchdog_data {
140 unsigned short sioaddr;
141 enum chips type;
142 unsigned long opened;
143 struct mutex lock;
144 char expect_close;
145 struct watchdog_info ident;
146
147 unsigned short timeout;
148 u8 timer_val; /* content for the wd_time register */
149 char minutes_mode;
150 u8 pulse_val; /* pulse width flag */
151 char pulse_mode; /* enable pulse output mode? */
152 char caused_reboot; /* last reboot was by the watchdog */
153 };
154
155 static struct watchdog_data watchdog = {
156 .lock = __MUTEX_INITIALIZER(watchdog.lock),
157 };
158
159 /* Super I/O functions */
superio_inb(int base,int reg)160 static inline int superio_inb(int base, int reg)
161 {
162 outb(reg, base);
163 return inb(base + 1);
164 }
165
superio_inw(int base,int reg)166 static int superio_inw(int base, int reg)
167 {
168 int val;
169 val = superio_inb(base, reg) << 8;
170 val |= superio_inb(base, reg + 1);
171 return val;
172 }
173
superio_outb(int base,int reg,u8 val)174 static inline void superio_outb(int base, int reg, u8 val)
175 {
176 outb(reg, base);
177 outb(val, base + 1);
178 }
179
superio_set_bit(int base,int reg,int bit)180 static inline void superio_set_bit(int base, int reg, int bit)
181 {
182 unsigned long val = superio_inb(base, reg);
183 __set_bit(bit, &val);
184 superio_outb(base, reg, val);
185 }
186
superio_clear_bit(int base,int reg,int bit)187 static inline void superio_clear_bit(int base, int reg, int bit)
188 {
189 unsigned long val = superio_inb(base, reg);
190 __clear_bit(bit, &val);
191 superio_outb(base, reg, val);
192 }
193
superio_enter(int base)194 static inline int superio_enter(int base)
195 {
196 /* Don't step on other drivers' I/O space by accident */
197 if (!request_muxed_region(base, 2, DRVNAME)) {
198 pr_err("I/O address 0x%04x already in use\n", (int)base);
199 return -EBUSY;
200 }
201
202 /* according to the datasheet the key must be sent twice! */
203 outb(SIO_UNLOCK_KEY, base);
204 outb(SIO_UNLOCK_KEY, base);
205
206 return 0;
207 }
208
superio_select(int base,int ld)209 static inline void superio_select(int base, int ld)
210 {
211 outb(SIO_REG_LDSEL, base);
212 outb(ld, base + 1);
213 }
214
superio_exit(int base)215 static inline void superio_exit(int base)
216 {
217 outb(SIO_LOCK_KEY, base);
218 release_region(base, 2);
219 }
220
watchdog_set_timeout(int timeout)221 static int watchdog_set_timeout(int timeout)
222 {
223 if (timeout <= 0
224 || timeout > max_timeout) {
225 pr_err("watchdog timeout out of range\n");
226 return -EINVAL;
227 }
228
229 mutex_lock(&watchdog.lock);
230
231 if (timeout > 0xff) {
232 watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
233 watchdog.minutes_mode = true;
234 timeout = watchdog.timer_val * 60;
235 } else {
236 watchdog.timer_val = timeout;
237 watchdog.minutes_mode = false;
238 }
239
240 watchdog.timeout = timeout;
241
242 mutex_unlock(&watchdog.lock);
243
244 return 0;
245 }
246
watchdog_set_pulse_width(unsigned int pw)247 static int watchdog_set_pulse_width(unsigned int pw)
248 {
249 int err = 0;
250 unsigned int t1 = 25, t2 = 125, t3 = 5000;
251
252 if (watchdog.type == f71868) {
253 t1 = 30;
254 t2 = 150;
255 t3 = 6000;
256 }
257
258 mutex_lock(&watchdog.lock);
259
260 if (pw <= 1) {
261 watchdog.pulse_val = 0;
262 } else if (pw <= t1) {
263 watchdog.pulse_val = 1;
264 } else if (pw <= t2) {
265 watchdog.pulse_val = 2;
266 } else if (pw <= t3) {
267 watchdog.pulse_val = 3;
268 } else {
269 pr_err("pulse width out of range\n");
270 err = -EINVAL;
271 goto exit_unlock;
272 }
273
274 watchdog.pulse_mode = pw;
275
276 exit_unlock:
277 mutex_unlock(&watchdog.lock);
278 return err;
279 }
280
watchdog_keepalive(void)281 static int watchdog_keepalive(void)
282 {
283 int err = 0;
284
285 mutex_lock(&watchdog.lock);
286 err = superio_enter(watchdog.sioaddr);
287 if (err)
288 goto exit_unlock;
289 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
290
291 if (watchdog.minutes_mode)
292 /* select minutes for timer units */
293 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
294 F71808FG_FLAG_WD_UNIT);
295 else
296 /* select seconds for timer units */
297 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
298 F71808FG_FLAG_WD_UNIT);
299
300 /* Set timer value */
301 superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
302 watchdog.timer_val);
303
304 superio_exit(watchdog.sioaddr);
305
306 exit_unlock:
307 mutex_unlock(&watchdog.lock);
308 return err;
309 }
310
watchdog_start(void)311 static int watchdog_start(void)
312 {
313 int err;
314 u8 tmp;
315
316 /* Make sure we don't die as soon as the watchdog is enabled below */
317 err = watchdog_keepalive();
318 if (err)
319 return err;
320
321 mutex_lock(&watchdog.lock);
322 err = superio_enter(watchdog.sioaddr);
323 if (err)
324 goto exit_unlock;
325 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
326
327 /* Watchdog pin configuration */
328 switch (watchdog.type) {
329 case f71808fg:
330 /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
331 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
332 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
333 break;
334
335 case f71862fg:
336 if (f71862fg_pin == 63) {
337 /* SPI must be disabled first to use this pin! */
338 superio_clear_bit(watchdog.sioaddr, SIO_REG_ROM_ADDR_SEL, 6);
339 superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 4);
340 } else if (f71862fg_pin == 56) {
341 superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
342 }
343 break;
344
345 case f71868:
346 case f71869:
347 /* GPIO14 --> WDTRST# */
348 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 4);
349 break;
350
351 case f71882fg:
352 /* Set pin 56 to WDTRST# */
353 superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
354 break;
355
356 case f71889fg:
357 /* set pin 40 to WDTRST# */
358 superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
359 superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
360 break;
361
362 case f81803:
363 /* Enable TSI Level register bank */
364 superio_clear_bit(watchdog.sioaddr, SIO_REG_CLOCK_SEL, 3);
365 /* Set pin 27 to WDTRST# */
366 superio_outb(watchdog.sioaddr, SIO_REG_TSI_LEVEL_SEL, 0x5f &
367 superio_inb(watchdog.sioaddr, SIO_REG_TSI_LEVEL_SEL));
368 break;
369
370 case f81865:
371 /* Set pin 70 to WDTRST# */
372 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 5);
373 break;
374
375 case f81866:
376 /*
377 * GPIO1 Control Register when 27h BIT3:2 = 01 & BIT0 = 0.
378 * The PIN 70(GPIO15/WDTRST) is controlled by 2Ch:
379 * BIT5: 0 -> WDTRST#
380 * 1 -> GPIO15
381 */
382 tmp = superio_inb(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL);
383 tmp &= ~(BIT(3) | BIT(0));
384 tmp |= BIT(2);
385 superio_outb(watchdog.sioaddr, SIO_F81866_REG_PORT_SEL, tmp);
386
387 superio_clear_bit(watchdog.sioaddr, SIO_F81866_REG_GPIO1, 5);
388 break;
389
390 default:
391 /*
392 * 'default' label to shut up the compiler and catch
393 * programmer errors
394 */
395 err = -ENODEV;
396 goto exit_superio;
397 }
398
399 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
400 superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
401
402 if (watchdog.type == f81865 || watchdog.type == f81866)
403 superio_set_bit(watchdog.sioaddr, F81865_REG_WDO_CONF,
404 F81865_FLAG_WDOUT_EN);
405 else
406 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
407 F71808FG_FLAG_WDOUT_EN);
408
409 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
410 F71808FG_FLAG_WD_EN);
411
412 if (watchdog.pulse_mode) {
413 /* Select "pulse" output mode with given duration */
414 u8 wdt_conf = superio_inb(watchdog.sioaddr,
415 F71808FG_REG_WDT_CONF);
416
417 /* Set WD_PSWIDTH bits (1:0) */
418 wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
419 /* Set WD_PULSE to "pulse" mode */
420 wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
421
422 superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
423 wdt_conf);
424 } else {
425 /* Select "level" output mode */
426 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
427 F71808FG_FLAG_WD_PULSE);
428 }
429
430 exit_superio:
431 superio_exit(watchdog.sioaddr);
432 exit_unlock:
433 mutex_unlock(&watchdog.lock);
434
435 return err;
436 }
437
watchdog_stop(void)438 static int watchdog_stop(void)
439 {
440 int err = 0;
441
442 mutex_lock(&watchdog.lock);
443 err = superio_enter(watchdog.sioaddr);
444 if (err)
445 goto exit_unlock;
446 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
447
448 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
449 F71808FG_FLAG_WD_EN);
450
451 superio_exit(watchdog.sioaddr);
452
453 exit_unlock:
454 mutex_unlock(&watchdog.lock);
455
456 return err;
457 }
458
watchdog_get_status(void)459 static int watchdog_get_status(void)
460 {
461 int status = 0;
462
463 mutex_lock(&watchdog.lock);
464 status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
465 mutex_unlock(&watchdog.lock);
466
467 return status;
468 }
469
watchdog_is_running(void)470 static bool watchdog_is_running(void)
471 {
472 /*
473 * if we fail to determine the watchdog's status assume it to be
474 * running to be on the safe side
475 */
476 bool is_running = true;
477
478 mutex_lock(&watchdog.lock);
479 if (superio_enter(watchdog.sioaddr))
480 goto exit_unlock;
481 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
482
483 is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
484 && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
485 & BIT(F71808FG_FLAG_WD_EN));
486
487 superio_exit(watchdog.sioaddr);
488
489 exit_unlock:
490 mutex_unlock(&watchdog.lock);
491 return is_running;
492 }
493
494 /* /dev/watchdog api */
495
watchdog_open(struct inode * inode,struct file * file)496 static int watchdog_open(struct inode *inode, struct file *file)
497 {
498 int err;
499
500 /* If the watchdog is alive we don't need to start it again */
501 if (test_and_set_bit(0, &watchdog.opened))
502 return -EBUSY;
503
504 err = watchdog_start();
505 if (err) {
506 clear_bit(0, &watchdog.opened);
507 return err;
508 }
509
510 if (nowayout)
511 __module_get(THIS_MODULE);
512
513 watchdog.expect_close = 0;
514 return stream_open(inode, file);
515 }
516
watchdog_release(struct inode * inode,struct file * file)517 static int watchdog_release(struct inode *inode, struct file *file)
518 {
519 clear_bit(0, &watchdog.opened);
520
521 if (!watchdog.expect_close) {
522 watchdog_keepalive();
523 pr_crit("Unexpected close, not stopping watchdog!\n");
524 } else if (!nowayout) {
525 watchdog_stop();
526 }
527 return 0;
528 }
529
530 /*
531 * watchdog_write:
532 * @file: file handle to the watchdog
533 * @buf: buffer to write
534 * @count: count of bytes
535 * @ppos: pointer to the position to write. No seeks allowed
536 *
537 * A write to a watchdog device is defined as a keepalive signal. Any
538 * write of data will do, as we we don't define content meaning.
539 */
540
watchdog_write(struct file * file,const char __user * buf,size_t count,loff_t * ppos)541 static ssize_t watchdog_write(struct file *file, const char __user *buf,
542 size_t count, loff_t *ppos)
543 {
544 if (count) {
545 if (!nowayout) {
546 size_t i;
547
548 /* In case it was set long ago */
549 bool expect_close = false;
550
551 for (i = 0; i != count; i++) {
552 char c;
553 if (get_user(c, buf + i))
554 return -EFAULT;
555 if (c == 'V')
556 expect_close = true;
557 }
558
559 /* Properly order writes across fork()ed processes */
560 mutex_lock(&watchdog.lock);
561 watchdog.expect_close = expect_close;
562 mutex_unlock(&watchdog.lock);
563 }
564
565 /* someone wrote to us, we should restart timer */
566 watchdog_keepalive();
567 }
568 return count;
569 }
570
571 /*
572 * watchdog_ioctl:
573 * @inode: inode of the device
574 * @file: file handle to the device
575 * @cmd: watchdog command
576 * @arg: argument pointer
577 *
578 * The watchdog API defines a common set of functions for all watchdogs
579 * according to their available features.
580 */
watchdog_ioctl(struct file * file,unsigned int cmd,unsigned long arg)581 static long watchdog_ioctl(struct file *file, unsigned int cmd,
582 unsigned long arg)
583 {
584 int status;
585 int new_options;
586 int new_timeout;
587 union {
588 struct watchdog_info __user *ident;
589 int __user *i;
590 } uarg;
591
592 uarg.i = (int __user *)arg;
593
594 switch (cmd) {
595 case WDIOC_GETSUPPORT:
596 return copy_to_user(uarg.ident, &watchdog.ident,
597 sizeof(watchdog.ident)) ? -EFAULT : 0;
598
599 case WDIOC_GETSTATUS:
600 status = watchdog_get_status();
601 if (status < 0)
602 return status;
603 return put_user(status, uarg.i);
604
605 case WDIOC_GETBOOTSTATUS:
606 return put_user(0, uarg.i);
607
608 case WDIOC_SETOPTIONS:
609 if (get_user(new_options, uarg.i))
610 return -EFAULT;
611
612 if (new_options & WDIOS_DISABLECARD)
613 watchdog_stop();
614
615 if (new_options & WDIOS_ENABLECARD)
616 return watchdog_start();
617 fallthrough;
618
619 case WDIOC_KEEPALIVE:
620 watchdog_keepalive();
621 return 0;
622
623 case WDIOC_SETTIMEOUT:
624 if (get_user(new_timeout, uarg.i))
625 return -EFAULT;
626
627 if (watchdog_set_timeout(new_timeout))
628 return -EINVAL;
629
630 watchdog_keepalive();
631 fallthrough;
632
633 case WDIOC_GETTIMEOUT:
634 return put_user(watchdog.timeout, uarg.i);
635
636 default:
637 return -ENOTTY;
638
639 }
640 }
641
watchdog_notify_sys(struct notifier_block * this,unsigned long code,void * unused)642 static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
643 void *unused)
644 {
645 if (code == SYS_DOWN || code == SYS_HALT)
646 watchdog_stop();
647 return NOTIFY_DONE;
648 }
649
650 static const struct file_operations watchdog_fops = {
651 .owner = THIS_MODULE,
652 .llseek = no_llseek,
653 .open = watchdog_open,
654 .release = watchdog_release,
655 .write = watchdog_write,
656 .unlocked_ioctl = watchdog_ioctl,
657 .compat_ioctl = compat_ptr_ioctl,
658 };
659
660 static struct miscdevice watchdog_miscdev = {
661 .minor = WATCHDOG_MINOR,
662 .name = "watchdog",
663 .fops = &watchdog_fops,
664 };
665
666 static struct notifier_block watchdog_notifier = {
667 .notifier_call = watchdog_notify_sys,
668 };
669
watchdog_init(int sioaddr)670 static int __init watchdog_init(int sioaddr)
671 {
672 int wdt_conf, err = 0;
673
674 /* No need to lock watchdog.lock here because no entry points
675 * into the module have been registered yet.
676 */
677 watchdog.sioaddr = sioaddr;
678 watchdog.ident.options = WDIOF_MAGICCLOSE
679 | WDIOF_KEEPALIVEPING
680 | WDIOF_CARDRESET;
681
682 snprintf(watchdog.ident.identity,
683 sizeof(watchdog.ident.identity), "%s watchdog",
684 f71808e_names[watchdog.type]);
685
686 err = superio_enter(sioaddr);
687 if (err)
688 return err;
689 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
690
691 wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
692 watchdog.caused_reboot = wdt_conf & BIT(F71808FG_FLAG_WDTMOUT_STS);
693
694 /*
695 * We don't want WDTMOUT_STS to stick around till regular reboot.
696 * Write 1 to the bit to clear it to zero.
697 */
698 superio_outb(sioaddr, F71808FG_REG_WDT_CONF,
699 wdt_conf | BIT(F71808FG_FLAG_WDTMOUT_STS));
700
701 superio_exit(sioaddr);
702
703 err = watchdog_set_timeout(timeout);
704 if (err)
705 return err;
706 err = watchdog_set_pulse_width(pulse_width);
707 if (err)
708 return err;
709
710 err = register_reboot_notifier(&watchdog_notifier);
711 if (err)
712 return err;
713
714 err = misc_register(&watchdog_miscdev);
715 if (err) {
716 pr_err("cannot register miscdev on minor=%d\n",
717 watchdog_miscdev.minor);
718 goto exit_reboot;
719 }
720
721 if (start_withtimeout) {
722 if (start_withtimeout <= 0
723 || start_withtimeout > max_timeout) {
724 pr_err("starting timeout out of range\n");
725 err = -EINVAL;
726 goto exit_miscdev;
727 }
728
729 err = watchdog_start();
730 if (err) {
731 pr_err("cannot start watchdog timer\n");
732 goto exit_miscdev;
733 }
734
735 mutex_lock(&watchdog.lock);
736 err = superio_enter(sioaddr);
737 if (err)
738 goto exit_unlock;
739 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
740
741 if (start_withtimeout > 0xff) {
742 /* select minutes for timer units */
743 superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
744 F71808FG_FLAG_WD_UNIT);
745 superio_outb(sioaddr, F71808FG_REG_WD_TIME,
746 DIV_ROUND_UP(start_withtimeout, 60));
747 } else {
748 /* select seconds for timer units */
749 superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
750 F71808FG_FLAG_WD_UNIT);
751 superio_outb(sioaddr, F71808FG_REG_WD_TIME,
752 start_withtimeout);
753 }
754
755 superio_exit(sioaddr);
756 mutex_unlock(&watchdog.lock);
757
758 if (nowayout)
759 __module_get(THIS_MODULE);
760
761 pr_info("watchdog started with initial timeout of %u sec\n",
762 start_withtimeout);
763 }
764
765 return 0;
766
767 exit_unlock:
768 mutex_unlock(&watchdog.lock);
769 exit_miscdev:
770 misc_deregister(&watchdog_miscdev);
771 exit_reboot:
772 unregister_reboot_notifier(&watchdog_notifier);
773
774 return err;
775 }
776
f71808e_find(int sioaddr)777 static int __init f71808e_find(int sioaddr)
778 {
779 u16 devid;
780 int err = superio_enter(sioaddr);
781 if (err)
782 return err;
783
784 devid = superio_inw(sioaddr, SIO_REG_MANID);
785 if (devid != SIO_FINTEK_ID) {
786 pr_debug("Not a Fintek device\n");
787 err = -ENODEV;
788 goto exit;
789 }
790
791 devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
792 switch (devid) {
793 case SIO_F71808_ID:
794 watchdog.type = f71808fg;
795 break;
796 case SIO_F71862_ID:
797 watchdog.type = f71862fg;
798 break;
799 case SIO_F71868_ID:
800 watchdog.type = f71868;
801 break;
802 case SIO_F71869_ID:
803 case SIO_F71869A_ID:
804 watchdog.type = f71869;
805 break;
806 case SIO_F71882_ID:
807 watchdog.type = f71882fg;
808 break;
809 case SIO_F71889_ID:
810 watchdog.type = f71889fg;
811 break;
812 case SIO_F71858_ID:
813 /* Confirmed (by datasheet) not to have a watchdog. */
814 err = -ENODEV;
815 goto exit;
816 case SIO_F81803_ID:
817 watchdog.type = f81803;
818 break;
819 case SIO_F81865_ID:
820 watchdog.type = f81865;
821 break;
822 case SIO_F81866_ID:
823 watchdog.type = f81866;
824 break;
825 default:
826 pr_info("Unrecognized Fintek device: %04x\n",
827 (unsigned int)devid);
828 err = -ENODEV;
829 goto exit;
830 }
831
832 pr_info("Found %s watchdog chip, revision %d\n",
833 f71808e_names[watchdog.type],
834 (int)superio_inb(sioaddr, SIO_REG_DEVREV));
835 exit:
836 superio_exit(sioaddr);
837 return err;
838 }
839
f71808e_init(void)840 static int __init f71808e_init(void)
841 {
842 static const unsigned short addrs[] = { 0x2e, 0x4e };
843 int err = -ENODEV;
844 int i;
845
846 if (f71862fg_pin != 63 && f71862fg_pin != 56) {
847 pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin);
848 return -EINVAL;
849 }
850
851 for (i = 0; i < ARRAY_SIZE(addrs); i++) {
852 err = f71808e_find(addrs[i]);
853 if (err == 0)
854 break;
855 }
856 if (i == ARRAY_SIZE(addrs))
857 return err;
858
859 return watchdog_init(addrs[i]);
860 }
861
f71808e_exit(void)862 static void __exit f71808e_exit(void)
863 {
864 if (watchdog_is_running()) {
865 pr_warn("Watchdog timer still running, stopping it\n");
866 watchdog_stop();
867 }
868 misc_deregister(&watchdog_miscdev);
869 unregister_reboot_notifier(&watchdog_notifier);
870 }
871
872 MODULE_DESCRIPTION("F71808E Watchdog Driver");
873 MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
874 MODULE_LICENSE("GPL");
875
876 module_init(f71808e_init);
877 module_exit(f71808e_exit);
878