diff options
Diffstat (limited to 'drivers/watchdog/w83977f_wdt.c')
-rw-r--r-- | drivers/watchdog/w83977f_wdt.c | 542 |
1 files changed, 542 insertions, 0 deletions
diff --git a/drivers/watchdog/w83977f_wdt.c b/drivers/watchdog/w83977f_wdt.c new file mode 100644 index 000000000000..157968442891 --- /dev/null +++ b/drivers/watchdog/w83977f_wdt.c | |||
@@ -0,0 +1,542 @@ | |||
1 | /* | ||
2 | * W83977F Watchdog Timer Driver for Winbond W83977F I/O Chip | ||
3 | * | ||
4 | * (c) Copyright 2005 Jose Goncalves <jose.goncalves@inov.pt> | ||
5 | * | ||
6 | * Based on w83877f_wdt.c by Scott Jennings, | ||
7 | * and wdt977.c by Woody Suwalski | ||
8 | * | ||
9 | * ----------------------- | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or | ||
12 | * modify it under the terms of the GNU General Public License | ||
13 | * as published by the Free Software Foundation; either version | ||
14 | * 2 of the License, or (at your option) any later version. | ||
15 | * | ||
16 | */ | ||
17 | |||
18 | #include <linux/module.h> | ||
19 | #include <linux/moduleparam.h> | ||
20 | #include <linux/types.h> | ||
21 | #include <linux/kernel.h> | ||
22 | #include <linux/fs.h> | ||
23 | #include <linux/miscdevice.h> | ||
24 | #include <linux/init.h> | ||
25 | #include <linux/ioport.h> | ||
26 | #include <linux/watchdog.h> | ||
27 | #include <linux/notifier.h> | ||
28 | #include <linux/reboot.h> | ||
29 | |||
30 | #include <asm/io.h> | ||
31 | #include <asm/system.h> | ||
32 | #include <asm/uaccess.h> | ||
33 | |||
34 | #define WATCHDOG_VERSION "1.00" | ||
35 | #define WATCHDOG_NAME "W83977F WDT" | ||
36 | #define PFX WATCHDOG_NAME ": " | ||
37 | #define DRIVER_VERSION WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n" | ||
38 | |||
39 | #define IO_INDEX_PORT 0x3F0 | ||
40 | #define IO_DATA_PORT (IO_INDEX_PORT+1) | ||
41 | |||
42 | #define UNLOCK_DATA 0x87 | ||
43 | #define LOCK_DATA 0xAA | ||
44 | #define DEVICE_REGISTER 0x07 | ||
45 | |||
46 | #define DEFAULT_TIMEOUT 45 /* default timeout in seconds */ | ||
47 | |||
48 | static int timeout = DEFAULT_TIMEOUT; | ||
49 | static int timeoutW; /* timeout in watchdog counter units */ | ||
50 | static unsigned long timer_alive; | ||
51 | static int testmode; | ||
52 | static char expect_close; | ||
53 | static spinlock_t spinlock; | ||
54 | |||
55 | module_param(timeout, int, 0); | ||
56 | MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (15..7635), default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")"); | ||
57 | module_param(testmode, int, 0); | ||
58 | MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0"); | ||
59 | |||
60 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
61 | module_param(nowayout, int, 0); | ||
62 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
63 | |||
64 | /* | ||
65 | * Start the watchdog | ||
66 | */ | ||
67 | |||
68 | static int wdt_start(void) | ||
69 | { | ||
70 | unsigned long flags; | ||
71 | |||
72 | spin_lock_irqsave(&spinlock, flags); | ||
73 | |||
74 | /* Unlock the SuperIO chip */ | ||
75 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
76 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
77 | |||
78 | /* | ||
79 | * Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4. | ||
80 | * F2 has the timeout in watchdog counter units. | ||
81 | * F3 is set to enable watchdog LED blink at timeout. | ||
82 | * F4 is used to just clear the TIMEOUT'ed state (bit 0). | ||
83 | */ | ||
84 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
85 | outb_p(0x08,IO_DATA_PORT); | ||
86 | outb_p(0xF2,IO_INDEX_PORT); | ||
87 | outb_p(timeoutW,IO_DATA_PORT); | ||
88 | outb_p(0xF3,IO_INDEX_PORT); | ||
89 | outb_p(0x08,IO_DATA_PORT); | ||
90 | outb_p(0xF4,IO_INDEX_PORT); | ||
91 | outb_p(0x00,IO_DATA_PORT); | ||
92 | |||
93 | /* Set device Aux2 active */ | ||
94 | outb_p(0x30,IO_INDEX_PORT); | ||
95 | outb_p(0x01,IO_DATA_PORT); | ||
96 | |||
97 | /* | ||
98 | * Select device Aux1 (dev=7) to set GP16 as the watchdog output | ||
99 | * (in reg E6) and GP13 as the watchdog LED output (in reg E3). | ||
100 | * Map GP16 at pin 119. | ||
101 | * In test mode watch the bit 0 on F4 to indicate "triggered" or | ||
102 | * check watchdog LED on SBC. | ||
103 | */ | ||
104 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
105 | outb_p(0x07,IO_DATA_PORT); | ||
106 | if (!testmode) | ||
107 | { | ||
108 | unsigned pin_map; | ||
109 | |||
110 | outb_p(0xE6,IO_INDEX_PORT); | ||
111 | outb_p(0x0A,IO_DATA_PORT); | ||
112 | outb_p(0x2C,IO_INDEX_PORT); | ||
113 | pin_map = inb_p(IO_DATA_PORT); | ||
114 | pin_map |= 0x10; | ||
115 | pin_map &= ~(0x20); | ||
116 | outb_p(0x2C,IO_INDEX_PORT); | ||
117 | outb_p(pin_map,IO_DATA_PORT); | ||
118 | } | ||
119 | outb_p(0xE3,IO_INDEX_PORT); | ||
120 | outb_p(0x08,IO_DATA_PORT); | ||
121 | |||
122 | /* Set device Aux1 active */ | ||
123 | outb_p(0x30,IO_INDEX_PORT); | ||
124 | outb_p(0x01,IO_DATA_PORT); | ||
125 | |||
126 | /* Lock the SuperIO chip */ | ||
127 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
128 | |||
129 | spin_unlock_irqrestore(&spinlock, flags); | ||
130 | |||
131 | printk(KERN_INFO PFX "activated.\n"); | ||
132 | |||
133 | return 0; | ||
134 | } | ||
135 | |||
136 | /* | ||
137 | * Stop the watchdog | ||
138 | */ | ||
139 | |||
140 | static int wdt_stop(void) | ||
141 | { | ||
142 | unsigned long flags; | ||
143 | |||
144 | spin_lock_irqsave(&spinlock, flags); | ||
145 | |||
146 | /* Unlock the SuperIO chip */ | ||
147 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
148 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
149 | |||
150 | /* | ||
151 | * Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4. | ||
152 | * F2 is reset to its default value (watchdog timer disabled). | ||
153 | * F3 is reset to its default state. | ||
154 | * F4 clears the TIMEOUT'ed state (bit 0) - back to default. | ||
155 | */ | ||
156 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
157 | outb_p(0x08,IO_DATA_PORT); | ||
158 | outb_p(0xF2,IO_INDEX_PORT); | ||
159 | outb_p(0xFF,IO_DATA_PORT); | ||
160 | outb_p(0xF3,IO_INDEX_PORT); | ||
161 | outb_p(0x00,IO_DATA_PORT); | ||
162 | outb_p(0xF4,IO_INDEX_PORT); | ||
163 | outb_p(0x00,IO_DATA_PORT); | ||
164 | outb_p(0xF2,IO_INDEX_PORT); | ||
165 | outb_p(0x00,IO_DATA_PORT); | ||
166 | |||
167 | /* | ||
168 | * Select device Aux1 (dev=7) to set GP16 (in reg E6) and | ||
169 | * Gp13 (in reg E3) as inputs. | ||
170 | */ | ||
171 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
172 | outb_p(0x07,IO_DATA_PORT); | ||
173 | if (!testmode) | ||
174 | { | ||
175 | outb_p(0xE6,IO_INDEX_PORT); | ||
176 | outb_p(0x01,IO_DATA_PORT); | ||
177 | } | ||
178 | outb_p(0xE3,IO_INDEX_PORT); | ||
179 | outb_p(0x01,IO_DATA_PORT); | ||
180 | |||
181 | /* Lock the SuperIO chip */ | ||
182 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
183 | |||
184 | spin_unlock_irqrestore(&spinlock, flags); | ||
185 | |||
186 | printk(KERN_INFO PFX "shutdown.\n"); | ||
187 | |||
188 | return 0; | ||
189 | } | ||
190 | |||
191 | /* | ||
192 | * Send a keepalive ping to the watchdog | ||
193 | * This is done by simply re-writing the timeout to reg. 0xF2 | ||
194 | */ | ||
195 | |||
196 | static int wdt_keepalive(void) | ||
197 | { | ||
198 | unsigned long flags; | ||
199 | |||
200 | spin_lock_irqsave(&spinlock, flags); | ||
201 | |||
202 | /* Unlock the SuperIO chip */ | ||
203 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
204 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
205 | |||
206 | /* Select device Aux2 (device=8) to kick watchdog reg F2 */ | ||
207 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
208 | outb_p(0x08,IO_DATA_PORT); | ||
209 | outb_p(0xF2,IO_INDEX_PORT); | ||
210 | outb_p(timeoutW,IO_DATA_PORT); | ||
211 | |||
212 | /* Lock the SuperIO chip */ | ||
213 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
214 | |||
215 | spin_unlock_irqrestore(&spinlock, flags); | ||
216 | |||
217 | return 0; | ||
218 | } | ||
219 | |||
220 | /* | ||
221 | * Set the watchdog timeout value | ||
222 | */ | ||
223 | |||
224 | static int wdt_set_timeout(int t) | ||
225 | { | ||
226 | int tmrval; | ||
227 | |||
228 | /* | ||
229 | * Convert seconds to watchdog counter time units, rounding up. | ||
230 | * On PCM-5335 watchdog units are 30 seconds/step with 15 sec startup | ||
231 | * value. This information is supplied in the PCM-5335 manual and was | ||
232 | * checked by me on a real board. This is a bit strange because W83977f | ||
233 | * datasheet says counter unit is in minutes! | ||
234 | */ | ||
235 | if (t < 15) | ||
236 | return -EINVAL; | ||
237 | |||
238 | tmrval = ((t + 15) + 29) / 30; | ||
239 | |||
240 | if (tmrval > 255) | ||
241 | return -EINVAL; | ||
242 | |||
243 | /* | ||
244 | * timeout is the timeout in seconds, | ||
245 | * timeoutW is the timeout in watchdog counter units. | ||
246 | */ | ||
247 | timeoutW = tmrval; | ||
248 | timeout = (timeoutW * 30) - 15; | ||
249 | return 0; | ||
250 | } | ||
251 | |||
252 | /* | ||
253 | * Get the watchdog status | ||
254 | */ | ||
255 | |||
256 | static int wdt_get_status(int *status) | ||
257 | { | ||
258 | int new_status; | ||
259 | unsigned long flags; | ||
260 | |||
261 | spin_lock_irqsave(&spinlock, flags); | ||
262 | |||
263 | /* Unlock the SuperIO chip */ | ||
264 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
265 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
266 | |||
267 | /* Select device Aux2 (device=8) to read watchdog reg F4 */ | ||
268 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
269 | outb_p(0x08,IO_DATA_PORT); | ||
270 | outb_p(0xF4,IO_INDEX_PORT); | ||
271 | new_status = inb_p(IO_DATA_PORT); | ||
272 | |||
273 | /* Lock the SuperIO chip */ | ||
274 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
275 | |||
276 | spin_unlock_irqrestore(&spinlock, flags); | ||
277 | |||
278 | *status = 0; | ||
279 | if (new_status & 1) | ||
280 | *status |= WDIOF_CARDRESET; | ||
281 | |||
282 | return 0; | ||
283 | } | ||
284 | |||
285 | |||
286 | /* | ||
287 | * /dev/watchdog handling | ||
288 | */ | ||
289 | |||
290 | static int wdt_open(struct inode *inode, struct file *file) | ||
291 | { | ||
292 | /* If the watchdog is alive we don't need to start it again */ | ||
293 | if( test_and_set_bit(0, &timer_alive) ) | ||
294 | return -EBUSY; | ||
295 | |||
296 | if (nowayout) | ||
297 | __module_get(THIS_MODULE); | ||
298 | |||
299 | wdt_start(); | ||
300 | return nonseekable_open(inode, file); | ||
301 | } | ||
302 | |||
303 | static int wdt_release(struct inode *inode, struct file *file) | ||
304 | { | ||
305 | /* | ||
306 | * Shut off the timer. | ||
307 | * Lock it in if it's a module and we set nowayout | ||
308 | */ | ||
309 | if (expect_close == 42) | ||
310 | { | ||
311 | wdt_stop(); | ||
312 | clear_bit(0, &timer_alive); | ||
313 | } else { | ||
314 | wdt_keepalive(); | ||
315 | printk(KERN_CRIT PFX "unexpected close, not stopping watchdog!\n"); | ||
316 | } | ||
317 | expect_close = 0; | ||
318 | return 0; | ||
319 | } | ||
320 | |||
321 | /* | ||
322 | * wdt_write: | ||
323 | * @file: file handle to the watchdog | ||
324 | * @buf: buffer to write (unused as data does not matter here | ||
325 | * @count: count of bytes | ||
326 | * @ppos: pointer to the position to write. No seeks allowed | ||
327 | * | ||
328 | * A write to a watchdog device is defined as a keepalive signal. Any | ||
329 | * write of data will do, as we we don't define content meaning. | ||
330 | */ | ||
331 | |||
332 | static ssize_t wdt_write(struct file *file, const char __user *buf, | ||
333 | size_t count, loff_t *ppos) | ||
334 | { | ||
335 | /* See if we got the magic character 'V' and reload the timer */ | ||
336 | if(count) | ||
337 | { | ||
338 | if (!nowayout) | ||
339 | { | ||
340 | size_t ofs; | ||
341 | |||
342 | /* note: just in case someone wrote the magic character long ago */ | ||
343 | expect_close = 0; | ||
344 | |||
345 | /* scan to see whether or not we got the magic character */ | ||
346 | for(ofs = 0; ofs != count; ofs++) | ||
347 | { | ||
348 | char c; | ||
349 | if (get_user(c, buf + ofs)) | ||
350 | return -EFAULT; | ||
351 | if (c == 'V') { | ||
352 | expect_close = 42; | ||
353 | } | ||
354 | } | ||
355 | } | ||
356 | |||
357 | /* someone wrote to us, we should restart timer */ | ||
358 | wdt_keepalive(); | ||
359 | } | ||
360 | return count; | ||
361 | } | ||
362 | |||
363 | /* | ||
364 | * wdt_ioctl: | ||
365 | * @inode: inode of the device | ||
366 | * @file: file handle to the device | ||
367 | * @cmd: watchdog command | ||
368 | * @arg: argument pointer | ||
369 | * | ||
370 | * The watchdog API defines a common set of functions for all watchdogs | ||
371 | * according to their available features. | ||
372 | */ | ||
373 | |||
374 | static struct watchdog_info ident = { | ||
375 | .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, | ||
376 | .firmware_version = 1, | ||
377 | .identity = WATCHDOG_NAME, | ||
378 | }; | ||
379 | |||
380 | static int wdt_ioctl(struct inode *inode, struct file *file, | ||
381 | unsigned int cmd, unsigned long arg) | ||
382 | { | ||
383 | int status; | ||
384 | int new_options, retval = -EINVAL; | ||
385 | int new_timeout; | ||
386 | union { | ||
387 | struct watchdog_info __user *ident; | ||
388 | int __user *i; | ||
389 | } uarg; | ||
390 | |||
391 | uarg.i = (int __user *)arg; | ||
392 | |||
393 | switch(cmd) | ||
394 | { | ||
395 | default: | ||
396 | return -ENOTTY; | ||
397 | |||
398 | case WDIOC_GETSUPPORT: | ||
399 | return copy_to_user(uarg.ident, &ident, sizeof(ident)) ? -EFAULT : 0; | ||
400 | |||
401 | case WDIOC_GETSTATUS: | ||
402 | wdt_get_status(&status); | ||
403 | return put_user(status, uarg.i); | ||
404 | |||
405 | case WDIOC_GETBOOTSTATUS: | ||
406 | return put_user(0, uarg.i); | ||
407 | |||
408 | case WDIOC_KEEPALIVE: | ||
409 | wdt_keepalive(); | ||
410 | return 0; | ||
411 | |||
412 | case WDIOC_SETOPTIONS: | ||
413 | if (get_user (new_options, uarg.i)) | ||
414 | return -EFAULT; | ||
415 | |||
416 | if (new_options & WDIOS_DISABLECARD) { | ||
417 | wdt_stop(); | ||
418 | retval = 0; | ||
419 | } | ||
420 | |||
421 | if (new_options & WDIOS_ENABLECARD) { | ||
422 | wdt_start(); | ||
423 | retval = 0; | ||
424 | } | ||
425 | |||
426 | return retval; | ||
427 | |||
428 | case WDIOC_SETTIMEOUT: | ||
429 | if (get_user(new_timeout, uarg.i)) | ||
430 | return -EFAULT; | ||
431 | |||
432 | if (wdt_set_timeout(new_timeout)) | ||
433 | return -EINVAL; | ||
434 | |||
435 | wdt_keepalive(); | ||
436 | /* Fall */ | ||
437 | |||
438 | case WDIOC_GETTIMEOUT: | ||
439 | return put_user(timeout, uarg.i); | ||
440 | |||
441 | } | ||
442 | } | ||
443 | |||
444 | static int wdt_notify_sys(struct notifier_block *this, unsigned long code, | ||
445 | void *unused) | ||
446 | { | ||
447 | if (code==SYS_DOWN || code==SYS_HALT) | ||
448 | wdt_stop(); | ||
449 | return NOTIFY_DONE; | ||
450 | } | ||
451 | |||
452 | static const struct file_operations wdt_fops= | ||
453 | { | ||
454 | .owner = THIS_MODULE, | ||
455 | .llseek = no_llseek, | ||
456 | .write = wdt_write, | ||
457 | .ioctl = wdt_ioctl, | ||
458 | .open = wdt_open, | ||
459 | .release = wdt_release, | ||
460 | }; | ||
461 | |||
462 | static struct miscdevice wdt_miscdev= | ||
463 | { | ||
464 | .minor = WATCHDOG_MINOR, | ||
465 | .name = "watchdog", | ||
466 | .fops = &wdt_fops, | ||
467 | }; | ||
468 | |||
469 | static struct notifier_block wdt_notifier = { | ||
470 | .notifier_call = wdt_notify_sys, | ||
471 | }; | ||
472 | |||
473 | static int __init w83977f_wdt_init(void) | ||
474 | { | ||
475 | int rc; | ||
476 | |||
477 | printk(KERN_INFO PFX DRIVER_VERSION); | ||
478 | |||
479 | spin_lock_init(&spinlock); | ||
480 | |||
481 | /* | ||
482 | * Check that the timeout value is within it's range ; | ||
483 | * if not reset to the default | ||
484 | */ | ||
485 | if (wdt_set_timeout(timeout)) { | ||
486 | wdt_set_timeout(DEFAULT_TIMEOUT); | ||
487 | printk(KERN_INFO PFX "timeout value must be 15<=timeout<=7635, using %d\n", | ||
488 | DEFAULT_TIMEOUT); | ||
489 | } | ||
490 | |||
491 | if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME)) | ||
492 | { | ||
493 | printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", | ||
494 | IO_INDEX_PORT); | ||
495 | rc = -EIO; | ||
496 | goto err_out; | ||
497 | } | ||
498 | |||
499 | rc = misc_register(&wdt_miscdev); | ||
500 | if (rc) | ||
501 | { | ||
502 | printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | ||
503 | wdt_miscdev.minor, rc); | ||
504 | goto err_out_region; | ||
505 | } | ||
506 | |||
507 | rc = register_reboot_notifier(&wdt_notifier); | ||
508 | if (rc) | ||
509 | { | ||
510 | printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", | ||
511 | rc); | ||
512 | goto err_out_miscdev; | ||
513 | } | ||
514 | |||
515 | printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d testmode=%d)\n", | ||
516 | timeout, nowayout, testmode); | ||
517 | |||
518 | return 0; | ||
519 | |||
520 | err_out_miscdev: | ||
521 | misc_deregister(&wdt_miscdev); | ||
522 | err_out_region: | ||
523 | release_region(IO_INDEX_PORT,2); | ||
524 | err_out: | ||
525 | return rc; | ||
526 | } | ||
527 | |||
528 | static void __exit w83977f_wdt_exit(void) | ||
529 | { | ||
530 | wdt_stop(); | ||
531 | misc_deregister(&wdt_miscdev); | ||
532 | unregister_reboot_notifier(&wdt_notifier); | ||
533 | release_region(IO_INDEX_PORT,2); | ||
534 | } | ||
535 | |||
536 | module_init(w83977f_wdt_init); | ||
537 | module_exit(w83977f_wdt_exit); | ||
538 | |||
539 | MODULE_AUTHOR("Jose Goncalves <jose.goncalves@inov.pt>"); | ||
540 | MODULE_DESCRIPTION("Driver for watchdog timer in W83977F I/O chip"); | ||
541 | MODULE_LICENSE("GPL"); | ||
542 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||