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f71808e_wdt.c
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1 /***************************************************************************
2  * Copyright (C) 2006 by Hans Edgington <[email protected]> *
3  * Copyright (C) 2007-2009 Hans de Goede <[email protected]> *
4  * Copyright (C) 2010 Giel van Schijndel <[email protected]> *
5  * *
6  * This program is free software; you can redistribute it and/or modify *
7  * it under the terms of the GNU General Public License as published by *
8  * the Free Software Foundation; either version 2 of the License, or *
9  * (at your option) any later version. *
10  * *
11  * This program is distributed in the hope that it will be useful, *
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of *
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
14  * GNU General Public License for more details. *
15  * *
16  * You should have received a copy of the GNU General Public License *
17  * along with this program; if not, write to the *
18  * Free Software Foundation, Inc., *
19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
20  ***************************************************************************/
21 
22 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
23 
24 #include <linux/err.h>
25 #include <linux/fs.h>
26 #include <linux/init.h>
27 #include <linux/io.h>
28 #include <linux/ioport.h>
29 #include <linux/miscdevice.h>
30 #include <linux/module.h>
31 #include <linux/mutex.h>
32 #include <linux/notifier.h>
33 #include <linux/reboot.h>
34 #include <linux/uaccess.h>
35 #include <linux/watchdog.h>
36 
37 #define DRVNAME "f71808e_wdt"
38 
39 #define SIO_F71808FG_LD_WDT 0x07 /* Watchdog timer logical device */
40 #define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */
41 #define SIO_LOCK_KEY 0xAA /* Key to diasble Super-I/O */
42 
43 #define SIO_REG_LDSEL 0x07 /* Logical device select */
44 #define SIO_REG_DEVID 0x20 /* Device ID (2 bytes) */
45 #define SIO_REG_DEVREV 0x22 /* Device revision */
46 #define SIO_REG_MANID 0x23 /* Fintek ID (2 bytes) */
47 #define SIO_REG_ROM_ADDR_SEL 0x27 /* ROM address select */
48 #define SIO_REG_MFUNCT1 0x29 /* Multi function select 1 */
49 #define SIO_REG_MFUNCT2 0x2a /* Multi function select 2 */
50 #define SIO_REG_MFUNCT3 0x2b /* Multi function select 3 */
51 #define SIO_REG_ENABLE 0x30 /* Logical device enable */
52 #define SIO_REG_ADDR 0x60 /* Logical device address (2 bytes) */
53 
54 #define SIO_FINTEK_ID 0x1934 /* Manufacturers ID */
55 #define SIO_F71808_ID 0x0901 /* Chipset ID */
56 #define SIO_F71858_ID 0x0507 /* Chipset ID */
57 #define SIO_F71862_ID 0x0601 /* Chipset ID */
58 #define SIO_F71869_ID 0x0814 /* Chipset ID */
59 #define SIO_F71869A_ID 0x1007 /* Chipset ID */
60 #define SIO_F71882_ID 0x0541 /* Chipset ID */
61 #define SIO_F71889_ID 0x0723 /* Chipset ID */
62 
63 #define F71808FG_REG_WDO_CONF 0xf0
64 #define F71808FG_REG_WDT_CONF 0xf5
65 #define F71808FG_REG_WD_TIME 0xf6
66 
67 #define F71808FG_FLAG_WDOUT_EN 7
68 
69 #define F71808FG_FLAG_WDTMOUT_STS 5
70 #define F71808FG_FLAG_WD_EN 5
71 #define F71808FG_FLAG_WD_PULSE 4
72 #define F71808FG_FLAG_WD_UNIT 3
73 
74 /* Default values */
75 #define WATCHDOG_TIMEOUT 60 /* 1 minute default timeout */
76 #define WATCHDOG_MAX_TIMEOUT (60 * 255)
77 #define WATCHDOG_PULSE_WIDTH 125 /* 125 ms, default pulse width for
78  watchdog signal */
79 #define WATCHDOG_F71862FG_PIN 63 /* default watchdog reset output
80  pin number 63 */
81 
82 static unsigned short force_id;
83 module_param(force_id, ushort, 0);
84 MODULE_PARM_DESC(force_id, "Override the detected device ID");
85 
86 static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
87 static int timeout = WATCHDOG_TIMEOUT; /* default timeout in seconds */
88 module_param(timeout, int, 0);
89 MODULE_PARM_DESC(timeout,
90  "Watchdog timeout in seconds. 1<= timeout <="
91  __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
92  __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
93 
94 static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
95 module_param(pulse_width, uint, 0);
96 MODULE_PARM_DESC(pulse_width,
97  "Watchdog signal pulse width. 0(=level), 1 ms, 25 ms, 125 ms or 5000 ms"
98  " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
99 
100 static unsigned int f71862fg_pin = WATCHDOG_F71862FG_PIN;
101 module_param(f71862fg_pin, uint, 0);
102 MODULE_PARM_DESC(f71862fg_pin,
103  "Watchdog f71862fg reset output pin configuration. Choose pin 56 or 63"
104  " (default=" __MODULE_STRING(WATCHDOG_F71862FG_PIN)")");
105 
106 static bool nowayout = WATCHDOG_NOWAYOUT;
107 module_param(nowayout, bool, 0444);
108 MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
109 
110 static unsigned int start_withtimeout;
111 module_param(start_withtimeout, uint, 0);
112 MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
113  " given initial timeout. Zero (default) disables this feature.");
114 
115 enum chips { f71808fg, f71858fg, f71862fg, f71869, f71882fg, f71889fg };
116 
117 static const char *f71808e_names[] = {
118  "f71808fg",
119  "f71858fg",
120  "f71862fg",
121  "f71869",
122  "f71882fg",
123  "f71889fg",
124 };
125 
126 /* Super-I/O Function prototypes */
127 static inline int superio_inb(int base, int reg);
128 static inline int superio_inw(int base, int reg);
129 static inline void superio_outb(int base, int reg, u8 val);
130 static inline void superio_set_bit(int base, int reg, int bit);
131 static inline void superio_clear_bit(int base, int reg, int bit);
132 static inline int superio_enter(int base);
133 static inline void superio_select(int base, int ld);
134 static inline void superio_exit(int base);
135 
136 struct watchdog_data {
137  unsigned short sioaddr;
138  enum chips type;
139  unsigned long opened;
140  struct mutex lock;
141  char expect_close;
142  struct watchdog_info ident;
143 
144  unsigned short timeout;
145  u8 timer_val; /* content for the wd_time register */
146  char minutes_mode;
147  u8 pulse_val; /* pulse width flag */
148  char pulse_mode; /* enable pulse output mode? */
149  char caused_reboot; /* last reboot was by the watchdog */
150 };
151 
152 static struct watchdog_data watchdog = {
153  .lock = __MUTEX_INITIALIZER(watchdog.lock),
154 };
155 
156 /* Super I/O functions */
157 static inline int superio_inb(int base, int reg)
158 {
159  outb(reg, base);
160  return inb(base + 1);
161 }
162 
163 static int superio_inw(int base, int reg)
164 {
165  int val;
166  val = superio_inb(base, reg) << 8;
167  val |= superio_inb(base, reg + 1);
168  return val;
169 }
170 
171 static inline void superio_outb(int base, int reg, u8 val)
172 {
173  outb(reg, base);
174  outb(val, base + 1);
175 }
176 
177 static inline void superio_set_bit(int base, int reg, int bit)
178 {
179  unsigned long val = superio_inb(base, reg);
180  __set_bit(bit, &val);
181  superio_outb(base, reg, val);
182 }
183 
184 static inline void superio_clear_bit(int base, int reg, int bit)
185 {
186  unsigned long val = superio_inb(base, reg);
187  __clear_bit(bit, &val);
188  superio_outb(base, reg, val);
189 }
190 
191 static inline int superio_enter(int base)
192 {
193  /* Don't step on other drivers' I/O space by accident */
194  if (!request_muxed_region(base, 2, DRVNAME)) {
195  pr_err("I/O address 0x%04x already in use\n", (int)base);
196  return -EBUSY;
197  }
198 
199  /* according to the datasheet the key must be sent twice! */
200  outb(SIO_UNLOCK_KEY, base);
201  outb(SIO_UNLOCK_KEY, base);
202 
203  return 0;
204 }
205 
206 static inline void superio_select(int base, int ld)
207 {
208  outb(SIO_REG_LDSEL, base);
209  outb(ld, base + 1);
210 }
211 
212 static inline void superio_exit(int base)
213 {
214  outb(SIO_LOCK_KEY, base);
215  release_region(base, 2);
216 }
217 
218 static int watchdog_set_timeout(int timeout)
219 {
220  if (timeout <= 0
221  || timeout > max_timeout) {
222  pr_err("watchdog timeout out of range\n");
223  return -EINVAL;
224  }
225 
226  mutex_lock(&watchdog.lock);
227 
228  watchdog.timeout = timeout;
229  if (timeout > 0xff) {
230  watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
231  watchdog.minutes_mode = true;
232  } else {
233  watchdog.timer_val = timeout;
234  watchdog.minutes_mode = false;
235  }
236 
237  mutex_unlock(&watchdog.lock);
238 
239  return 0;
240 }
241 
242 static int watchdog_set_pulse_width(unsigned int pw)
243 {
244  int err = 0;
245 
246  mutex_lock(&watchdog.lock);
247 
248  if (pw <= 1) {
249  watchdog.pulse_val = 0;
250  } else if (pw <= 25) {
251  watchdog.pulse_val = 1;
252  } else if (pw <= 125) {
253  watchdog.pulse_val = 2;
254  } else if (pw <= 5000) {
255  watchdog.pulse_val = 3;
256  } else {
257  pr_err("pulse width out of range\n");
258  err = -EINVAL;
259  goto exit_unlock;
260  }
261 
262  watchdog.pulse_mode = pw;
263 
264 exit_unlock:
265  mutex_unlock(&watchdog.lock);
266  return err;
267 }
268 
269 static int watchdog_keepalive(void)
270 {
271  int err = 0;
272 
273  mutex_lock(&watchdog.lock);
274  err = superio_enter(watchdog.sioaddr);
275  if (err)
276  goto exit_unlock;
277  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
278 
279  if (watchdog.minutes_mode)
280  /* select minutes for timer units */
281  superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
282  F71808FG_FLAG_WD_UNIT);
283  else
284  /* select seconds for timer units */
285  superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
286  F71808FG_FLAG_WD_UNIT);
287 
288  /* Set timer value */
289  superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
290  watchdog.timer_val);
291 
292  superio_exit(watchdog.sioaddr);
293 
294 exit_unlock:
295  mutex_unlock(&watchdog.lock);
296  return err;
297 }
298 
299 static int f71862fg_pin_configure(unsigned short ioaddr)
300 {
301  /* When ioaddr is non-zero the calling function has to take care of
302  mutex handling and superio preparation! */
303 
304  if (f71862fg_pin == 63) {
305  if (ioaddr) {
306  /* SPI must be disabled first to use this pin! */
307  superio_clear_bit(ioaddr, SIO_REG_ROM_ADDR_SEL, 6);
308  superio_set_bit(ioaddr, SIO_REG_MFUNCT3, 4);
309  }
310  } else if (f71862fg_pin == 56) {
311  if (ioaddr)
312  superio_set_bit(ioaddr, SIO_REG_MFUNCT1, 1);
313  } else {
314  pr_err("Invalid argument f71862fg_pin=%d\n", f71862fg_pin);
315  return -EINVAL;
316  }
317  return 0;
318 }
319 
320 static int watchdog_start(void)
321 {
322  /* Make sure we don't die as soon as the watchdog is enabled below */
323  int err = watchdog_keepalive();
324  if (err)
325  return err;
326 
327  mutex_lock(&watchdog.lock);
328  err = superio_enter(watchdog.sioaddr);
329  if (err)
330  goto exit_unlock;
331  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
332 
333  /* Watchdog pin configuration */
334  switch (watchdog.type) {
335  case f71808fg:
336  /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
337  superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
338  superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
339  break;
340 
341  case f71862fg:
342  err = f71862fg_pin_configure(watchdog.sioaddr);
343  if (err)
344  goto exit_superio;
345  break;
346 
347  case f71869:
348  /* GPIO14 --> WDTRST# */
349  superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 4);
350  break;
351 
352  case f71882fg:
353  /* Set pin 56 to WDTRST# */
354  superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
355  break;
356 
357  case f71889fg:
358  /* set pin 40 to WDTRST# */
359  superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
360  superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
361  break;
362 
363  default:
364  /*
365  * 'default' label to shut up the compiler and catch
366  * programmer errors
367  */
368  err = -ENODEV;
369  goto exit_superio;
370  }
371 
372  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
373  superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
374  superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
375  F71808FG_FLAG_WDOUT_EN);
376 
377  superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
378  F71808FG_FLAG_WD_EN);
379 
380  if (watchdog.pulse_mode) {
381  /* Select "pulse" output mode with given duration */
382  u8 wdt_conf = superio_inb(watchdog.sioaddr,
383  F71808FG_REG_WDT_CONF);
384 
385  /* Set WD_PSWIDTH bits (1:0) */
386  wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
387  /* Set WD_PULSE to "pulse" mode */
388  wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
389 
390  superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
391  wdt_conf);
392  } else {
393  /* Select "level" output mode */
394  superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
395  F71808FG_FLAG_WD_PULSE);
396  }
397 
398 exit_superio:
399  superio_exit(watchdog.sioaddr);
400 exit_unlock:
401  mutex_unlock(&watchdog.lock);
402 
403  return err;
404 }
405 
406 static int watchdog_stop(void)
407 {
408  int err = 0;
409 
410  mutex_lock(&watchdog.lock);
411  err = superio_enter(watchdog.sioaddr);
412  if (err)
413  goto exit_unlock;
414  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
415 
416  superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
417  F71808FG_FLAG_WD_EN);
418 
419  superio_exit(watchdog.sioaddr);
420 
421 exit_unlock:
422  mutex_unlock(&watchdog.lock);
423 
424  return err;
425 }
426 
427 static int watchdog_get_status(void)
428 {
429  int status = 0;
430 
431  mutex_lock(&watchdog.lock);
432  status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
433  mutex_unlock(&watchdog.lock);
434 
435  return status;
436 }
437 
438 static bool watchdog_is_running(void)
439 {
440  /*
441  * if we fail to determine the watchdog's status assume it to be
442  * running to be on the safe side
443  */
444  bool is_running = true;
445 
446  mutex_lock(&watchdog.lock);
447  if (superio_enter(watchdog.sioaddr))
448  goto exit_unlock;
449  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
450 
451  is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
452  && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
453  & F71808FG_FLAG_WD_EN);
454 
455  superio_exit(watchdog.sioaddr);
456 
457 exit_unlock:
458  mutex_unlock(&watchdog.lock);
459  return is_running;
460 }
461 
462 /* /dev/watchdog api */
463 
464 static int watchdog_open(struct inode *inode, struct file *file)
465 {
466  int err;
467 
468  /* If the watchdog is alive we don't need to start it again */
469  if (test_and_set_bit(0, &watchdog.opened))
470  return -EBUSY;
471 
472  err = watchdog_start();
473  if (err) {
474  clear_bit(0, &watchdog.opened);
475  return err;
476  }
477 
478  if (nowayout)
479  __module_get(THIS_MODULE);
480 
481  watchdog.expect_close = 0;
482  return nonseekable_open(inode, file);
483 }
484 
485 static int watchdog_release(struct inode *inode, struct file *file)
486 {
487  clear_bit(0, &watchdog.opened);
488 
489  if (!watchdog.expect_close) {
490  watchdog_keepalive();
491  pr_crit("Unexpected close, not stopping watchdog!\n");
492  } else if (!nowayout) {
493  watchdog_stop();
494  }
495  return 0;
496 }
497 
498 /*
499  * watchdog_write:
500  * @file: file handle to the watchdog
501  * @buf: buffer to write
502  * @count: count of bytes
503  * @ppos: pointer to the position to write. No seeks allowed
504  *
505  * A write to a watchdog device is defined as a keepalive signal. Any
506  * write of data will do, as we we don't define content meaning.
507  */
508 
509 static ssize_t watchdog_write(struct file *file, const char __user *buf,
510  size_t count, loff_t *ppos)
511 {
512  if (count) {
513  if (!nowayout) {
514  size_t i;
515 
516  /* In case it was set long ago */
517  bool expect_close = false;
518 
519  for (i = 0; i != count; i++) {
520  char c;
521  if (get_user(c, buf + i))
522  return -EFAULT;
523  expect_close = (c == 'V');
524  }
525 
526  /* Properly order writes across fork()ed processes */
527  mutex_lock(&watchdog.lock);
528  watchdog.expect_close = expect_close;
529  mutex_unlock(&watchdog.lock);
530  }
531 
532  /* someone wrote to us, we should restart timer */
533  watchdog_keepalive();
534  }
535  return count;
536 }
537 
538 /*
539  * watchdog_ioctl:
540  * @inode: inode of the device
541  * @file: file handle to the device
542  * @cmd: watchdog command
543  * @arg: argument pointer
544  *
545  * The watchdog API defines a common set of functions for all watchdogs
546  * according to their available features.
547  */
548 static long watchdog_ioctl(struct file *file, unsigned int cmd,
549  unsigned long arg)
550 {
551  int status;
552  int new_options;
553  int new_timeout;
554  union {
555  struct watchdog_info __user *ident;
556  int __user *i;
557  } uarg;
558 
559  uarg.i = (int __user *)arg;
560 
561  switch (cmd) {
562  case WDIOC_GETSUPPORT:
563  return copy_to_user(uarg.ident, &watchdog.ident,
564  sizeof(watchdog.ident)) ? -EFAULT : 0;
565 
566  case WDIOC_GETSTATUS:
567  status = watchdog_get_status();
568  if (status < 0)
569  return status;
570  return put_user(status, uarg.i);
571 
572  case WDIOC_GETBOOTSTATUS:
573  return put_user(0, uarg.i);
574 
575  case WDIOC_SETOPTIONS:
576  if (get_user(new_options, uarg.i))
577  return -EFAULT;
578 
579  if (new_options & WDIOS_DISABLECARD)
580  watchdog_stop();
581 
582  if (new_options & WDIOS_ENABLECARD)
583  return watchdog_start();
584 
585 
586  case WDIOC_KEEPALIVE:
587  watchdog_keepalive();
588  return 0;
589 
590  case WDIOC_SETTIMEOUT:
591  if (get_user(new_timeout, uarg.i))
592  return -EFAULT;
593 
594  if (watchdog_set_timeout(new_timeout))
595  return -EINVAL;
596 
597  watchdog_keepalive();
598  /* Fall */
599 
600  case WDIOC_GETTIMEOUT:
601  return put_user(watchdog.timeout, uarg.i);
602 
603  default:
604  return -ENOTTY;
605 
606  }
607 }
608 
609 static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
610  void *unused)
611 {
612  if (code == SYS_DOWN || code == SYS_HALT)
613  watchdog_stop();
614  return NOTIFY_DONE;
615 }
616 
617 static const struct file_operations watchdog_fops = {
618  .owner = THIS_MODULE,
619  .llseek = no_llseek,
620  .open = watchdog_open,
621  .release = watchdog_release,
622  .write = watchdog_write,
623  .unlocked_ioctl = watchdog_ioctl,
624 };
625 
626 static struct miscdevice watchdog_miscdev = {
627  .minor = WATCHDOG_MINOR,
628  .name = "watchdog",
629  .fops = &watchdog_fops,
630 };
631 
632 static struct notifier_block watchdog_notifier = {
633  .notifier_call = watchdog_notify_sys,
634 };
635 
636 static int __init watchdog_init(int sioaddr)
637 {
638  int wdt_conf, err = 0;
639 
640  /* No need to lock watchdog.lock here because no entry points
641  * into the module have been registered yet.
642  */
643  watchdog.sioaddr = sioaddr;
644  watchdog.ident.options = WDIOC_SETTIMEOUT
645  | WDIOF_MAGICCLOSE
646  | WDIOF_KEEPALIVEPING;
647 
648  snprintf(watchdog.ident.identity,
649  sizeof(watchdog.ident.identity), "%s watchdog",
650  f71808e_names[watchdog.type]);
651 
652  err = superio_enter(sioaddr);
653  if (err)
654  return err;
655  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
656 
657  wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
658  watchdog.caused_reboot = wdt_conf & F71808FG_FLAG_WDTMOUT_STS;
659 
660  superio_exit(sioaddr);
661 
662  err = watchdog_set_timeout(timeout);
663  if (err)
664  return err;
665  err = watchdog_set_pulse_width(pulse_width);
666  if (err)
667  return err;
668 
669  err = register_reboot_notifier(&watchdog_notifier);
670  if (err)
671  return err;
672 
673  err = misc_register(&watchdog_miscdev);
674  if (err) {
675  pr_err("cannot register miscdev on minor=%d\n",
676  watchdog_miscdev.minor);
677  goto exit_reboot;
678  }
679 
680  if (start_withtimeout) {
681  if (start_withtimeout <= 0
682  || start_withtimeout > max_timeout) {
683  pr_err("starting timeout out of range\n");
684  err = -EINVAL;
685  goto exit_miscdev;
686  }
687 
688  err = watchdog_start();
689  if (err) {
690  pr_err("cannot start watchdog timer\n");
691  goto exit_miscdev;
692  }
693 
694  mutex_lock(&watchdog.lock);
695  err = superio_enter(sioaddr);
696  if (err)
697  goto exit_unlock;
698  superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
699 
700  if (start_withtimeout > 0xff) {
701  /* select minutes for timer units */
702  superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
703  F71808FG_FLAG_WD_UNIT);
704  superio_outb(sioaddr, F71808FG_REG_WD_TIME,
705  DIV_ROUND_UP(start_withtimeout, 60));
706  } else {
707  /* select seconds for timer units */
708  superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
709  F71808FG_FLAG_WD_UNIT);
710  superio_outb(sioaddr, F71808FG_REG_WD_TIME,
711  start_withtimeout);
712  }
713 
714  superio_exit(sioaddr);
715  mutex_unlock(&watchdog.lock);
716 
717  if (nowayout)
718  __module_get(THIS_MODULE);
719 
720  pr_info("watchdog started with initial timeout of %u sec\n",
721  start_withtimeout);
722  }
723 
724  return 0;
725 
726 exit_unlock:
727  mutex_unlock(&watchdog.lock);
728 exit_miscdev:
729  misc_deregister(&watchdog_miscdev);
730 exit_reboot:
731  unregister_reboot_notifier(&watchdog_notifier);
732 
733  return err;
734 }
735 
736 static int __init f71808e_find(int sioaddr)
737 {
738  u16 devid;
739  int err = superio_enter(sioaddr);
740  if (err)
741  return err;
742 
743  devid = superio_inw(sioaddr, SIO_REG_MANID);
744  if (devid != SIO_FINTEK_ID) {
745  pr_debug("Not a Fintek device\n");
746  err = -ENODEV;
747  goto exit;
748  }
749 
750  devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
751  switch (devid) {
752  case SIO_F71808_ID:
753  watchdog.type = f71808fg;
754  break;
755  case SIO_F71862_ID:
756  watchdog.type = f71862fg;
757  err = f71862fg_pin_configure(0); /* validate module parameter */
758  break;
759  case SIO_F71869_ID:
760  case SIO_F71869A_ID:
761  watchdog.type = f71869;
762  break;
763  case SIO_F71882_ID:
764  watchdog.type = f71882fg;
765  break;
766  case SIO_F71889_ID:
767  watchdog.type = f71889fg;
768  break;
769  case SIO_F71858_ID:
770  /* Confirmed (by datasheet) not to have a watchdog. */
771  err = -ENODEV;
772  goto exit;
773  default:
774  pr_info("Unrecognized Fintek device: %04x\n",
775  (unsigned int)devid);
776  err = -ENODEV;
777  goto exit;
778  }
779 
780  pr_info("Found %s watchdog chip, revision %d\n",
781  f71808e_names[watchdog.type],
782  (int)superio_inb(sioaddr, SIO_REG_DEVREV));
783 exit:
784  superio_exit(sioaddr);
785  return err;
786 }
787 
788 static int __init f71808e_init(void)
789 {
790  static const unsigned short addrs[] = { 0x2e, 0x4e };
791  int err = -ENODEV;
792  int i;
793 
794  for (i = 0; i < ARRAY_SIZE(addrs); i++) {
795  err = f71808e_find(addrs[i]);
796  if (err == 0)
797  break;
798  }
799  if (i == ARRAY_SIZE(addrs))
800  return err;
801 
802  return watchdog_init(addrs[i]);
803 }
804 
805 static void __exit f71808e_exit(void)
806 {
807  if (watchdog_is_running()) {
808  pr_warn("Watchdog timer still running, stopping it\n");
809  watchdog_stop();
810  }
811  misc_deregister(&watchdog_miscdev);
812  unregister_reboot_notifier(&watchdog_notifier);
813 }
814 
815 MODULE_DESCRIPTION("F71808E Watchdog Driver");
816 MODULE_AUTHOR("Giel van Schijndel <[email protected]>");
817 MODULE_LICENSE("GPL");
818 
819 module_init(f71808e_init);
820 module_exit(f71808e_exit);
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