diff options
Diffstat (limited to 'drivers/char/watchdog/w83977f_wdt.c')
-rw-r--r-- | drivers/char/watchdog/w83977f_wdt.c | 543 |
1 files changed, 543 insertions, 0 deletions
diff --git a/drivers/char/watchdog/w83977f_wdt.c b/drivers/char/watchdog/w83977f_wdt.c new file mode 100644 index 000000000000..a7ff64c8921f --- /dev/null +++ b/drivers/char/watchdog/w83977f_wdt.c | |||
@@ -0,0 +1,543 @@ | |||
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/config.h> | ||
21 | #include <linux/types.h> | ||
22 | #include <linux/kernel.h> | ||
23 | #include <linux/fs.h> | ||
24 | #include <linux/miscdevice.h> | ||
25 | #include <linux/init.h> | ||
26 | #include <linux/ioport.h> | ||
27 | #include <linux/watchdog.h> | ||
28 | #include <linux/notifier.h> | ||
29 | #include <linux/reboot.h> | ||
30 | |||
31 | #include <asm/io.h> | ||
32 | #include <asm/system.h> | ||
33 | #include <asm/uaccess.h> | ||
34 | |||
35 | #define WATCHDOG_VERSION "1.00" | ||
36 | #define WATCHDOG_NAME "W83977F WDT" | ||
37 | #define PFX WATCHDOG_NAME ": " | ||
38 | #define DRIVER_VERSION WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n" | ||
39 | |||
40 | #define IO_INDEX_PORT 0x3F0 | ||
41 | #define IO_DATA_PORT (IO_INDEX_PORT+1) | ||
42 | |||
43 | #define UNLOCK_DATA 0x87 | ||
44 | #define LOCK_DATA 0xAA | ||
45 | #define DEVICE_REGISTER 0x07 | ||
46 | |||
47 | #define DEFAULT_TIMEOUT 45 /* default timeout in seconds */ | ||
48 | |||
49 | static int timeout = DEFAULT_TIMEOUT; | ||
50 | static int timeoutW; /* timeout in watchdog counter units */ | ||
51 | static unsigned long timer_alive; | ||
52 | static int testmode; | ||
53 | static char expect_close; | ||
54 | static spinlock_t spinlock; | ||
55 | |||
56 | module_param(timeout, int, 0); | ||
57 | MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (15..7635), default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")"); | ||
58 | module_param(testmode, int, 0); | ||
59 | MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0"); | ||
60 | |||
61 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
62 | module_param(nowayout, int, 0); | ||
63 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); | ||
64 | |||
65 | /* | ||
66 | * Start the watchdog | ||
67 | */ | ||
68 | |||
69 | static int wdt_start(void) | ||
70 | { | ||
71 | unsigned long flags; | ||
72 | |||
73 | spin_lock_irqsave(&spinlock, flags); | ||
74 | |||
75 | /* Unlock the SuperIO chip */ | ||
76 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
77 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
78 | |||
79 | /* | ||
80 | * Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4. | ||
81 | * F2 has the timeout in watchdog counter units. | ||
82 | * F3 is set to enable watchdog LED blink at timeout. | ||
83 | * F4 is used to just clear the TIMEOUT'ed state (bit 0). | ||
84 | */ | ||
85 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
86 | outb_p(0x08,IO_DATA_PORT); | ||
87 | outb_p(0xF2,IO_INDEX_PORT); | ||
88 | outb_p(timeoutW,IO_DATA_PORT); | ||
89 | outb_p(0xF3,IO_INDEX_PORT); | ||
90 | outb_p(0x08,IO_DATA_PORT); | ||
91 | outb_p(0xF4,IO_INDEX_PORT); | ||
92 | outb_p(0x00,IO_DATA_PORT); | ||
93 | |||
94 | /* Set device Aux2 active */ | ||
95 | outb_p(0x30,IO_INDEX_PORT); | ||
96 | outb_p(0x01,IO_DATA_PORT); | ||
97 | |||
98 | /* | ||
99 | * Select device Aux1 (dev=7) to set GP16 as the watchdog output | ||
100 | * (in reg E6) and GP13 as the watchdog LED output (in reg E3). | ||
101 | * Map GP16 at pin 119. | ||
102 | * In test mode watch the bit 0 on F4 to indicate "triggered" or | ||
103 | * check watchdog LED on SBC. | ||
104 | */ | ||
105 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
106 | outb_p(0x07,IO_DATA_PORT); | ||
107 | if (!testmode) | ||
108 | { | ||
109 | unsigned pin_map; | ||
110 | |||
111 | outb_p(0xE6,IO_INDEX_PORT); | ||
112 | outb_p(0x0A,IO_DATA_PORT); | ||
113 | outb_p(0x2C,IO_INDEX_PORT); | ||
114 | pin_map = inb_p(IO_DATA_PORT); | ||
115 | pin_map |= 0x10; | ||
116 | pin_map &= ~(0x20); | ||
117 | outb_p(0x2C,IO_INDEX_PORT); | ||
118 | outb_p(pin_map,IO_DATA_PORT); | ||
119 | } | ||
120 | outb_p(0xE3,IO_INDEX_PORT); | ||
121 | outb_p(0x08,IO_DATA_PORT); | ||
122 | |||
123 | /* Set device Aux1 active */ | ||
124 | outb_p(0x30,IO_INDEX_PORT); | ||
125 | outb_p(0x01,IO_DATA_PORT); | ||
126 | |||
127 | /* Lock the SuperIO chip */ | ||
128 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
129 | |||
130 | spin_unlock_irqrestore(&spinlock, flags); | ||
131 | |||
132 | printk(KERN_INFO PFX "activated.\n"); | ||
133 | |||
134 | return 0; | ||
135 | } | ||
136 | |||
137 | /* | ||
138 | * Stop the watchdog | ||
139 | */ | ||
140 | |||
141 | static int wdt_stop(void) | ||
142 | { | ||
143 | unsigned long flags; | ||
144 | |||
145 | spin_lock_irqsave(&spinlock, flags); | ||
146 | |||
147 | /* Unlock the SuperIO chip */ | ||
148 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
149 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
150 | |||
151 | /* | ||
152 | * Select device Aux2 (device=8) to set watchdog regs F2, F3 and F4. | ||
153 | * F2 is reset to its default value (watchdog timer disabled). | ||
154 | * F3 is reset to its default state. | ||
155 | * F4 clears the TIMEOUT'ed state (bit 0) - back to default. | ||
156 | */ | ||
157 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
158 | outb_p(0x08,IO_DATA_PORT); | ||
159 | outb_p(0xF2,IO_INDEX_PORT); | ||
160 | outb_p(0xFF,IO_DATA_PORT); | ||
161 | outb_p(0xF3,IO_INDEX_PORT); | ||
162 | outb_p(0x00,IO_DATA_PORT); | ||
163 | outb_p(0xF4,IO_INDEX_PORT); | ||
164 | outb_p(0x00,IO_DATA_PORT); | ||
165 | outb_p(0xF2,IO_INDEX_PORT); | ||
166 | outb_p(0x00,IO_DATA_PORT); | ||
167 | |||
168 | /* | ||
169 | * Select device Aux1 (dev=7) to set GP16 (in reg E6) and | ||
170 | * Gp13 (in reg E3) as inputs. | ||
171 | */ | ||
172 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
173 | outb_p(0x07,IO_DATA_PORT); | ||
174 | if (!testmode) | ||
175 | { | ||
176 | outb_p(0xE6,IO_INDEX_PORT); | ||
177 | outb_p(0x01,IO_DATA_PORT); | ||
178 | } | ||
179 | outb_p(0xE3,IO_INDEX_PORT); | ||
180 | outb_p(0x01,IO_DATA_PORT); | ||
181 | |||
182 | /* Lock the SuperIO chip */ | ||
183 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
184 | |||
185 | spin_unlock_irqrestore(&spinlock, flags); | ||
186 | |||
187 | printk(KERN_INFO PFX "shutdown.\n"); | ||
188 | |||
189 | return 0; | ||
190 | } | ||
191 | |||
192 | /* | ||
193 | * Send a keepalive ping to the watchdog | ||
194 | * This is done by simply re-writing the timeout to reg. 0xF2 | ||
195 | */ | ||
196 | |||
197 | static int wdt_keepalive(void) | ||
198 | { | ||
199 | unsigned long flags; | ||
200 | |||
201 | spin_lock_irqsave(&spinlock, flags); | ||
202 | |||
203 | /* Unlock the SuperIO chip */ | ||
204 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
205 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
206 | |||
207 | /* Select device Aux2 (device=8) to kick watchdog reg F2 */ | ||
208 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
209 | outb_p(0x08,IO_DATA_PORT); | ||
210 | outb_p(0xF2,IO_INDEX_PORT); | ||
211 | outb_p(timeoutW,IO_DATA_PORT); | ||
212 | |||
213 | /* Lock the SuperIO chip */ | ||
214 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
215 | |||
216 | spin_unlock_irqrestore(&spinlock, flags); | ||
217 | |||
218 | return 0; | ||
219 | } | ||
220 | |||
221 | /* | ||
222 | * Set the watchdog timeout value | ||
223 | */ | ||
224 | |||
225 | static int wdt_set_timeout(int t) | ||
226 | { | ||
227 | int tmrval; | ||
228 | |||
229 | /* | ||
230 | * Convert seconds to watchdog counter time units, rounding up. | ||
231 | * On PCM-5335 watchdog units are 30 seconds/step with 15 sec startup | ||
232 | * value. This information is supplied in the PCM-5335 manual and was | ||
233 | * checked by me on a real board. This is a bit strange because W83977f | ||
234 | * datasheet says counter unit is in minutes! | ||
235 | */ | ||
236 | if (t < 15) | ||
237 | return -EINVAL; | ||
238 | |||
239 | tmrval = ((t + 15) + 29) / 30; | ||
240 | |||
241 | if (tmrval > 255) | ||
242 | return -EINVAL; | ||
243 | |||
244 | /* | ||
245 | * timeout is the timeout in seconds, | ||
246 | * timeoutW is the timeout in watchdog counter units. | ||
247 | */ | ||
248 | timeoutW = tmrval; | ||
249 | timeout = (timeoutW * 30) - 15; | ||
250 | return 0; | ||
251 | } | ||
252 | |||
253 | /* | ||
254 | * Get the watchdog status | ||
255 | */ | ||
256 | |||
257 | static int wdt_get_status(int *status) | ||
258 | { | ||
259 | int new_status; | ||
260 | unsigned long flags; | ||
261 | |||
262 | spin_lock_irqsave(&spinlock, flags); | ||
263 | |||
264 | /* Unlock the SuperIO chip */ | ||
265 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
266 | outb_p(UNLOCK_DATA,IO_INDEX_PORT); | ||
267 | |||
268 | /* Select device Aux2 (device=8) to read watchdog reg F4 */ | ||
269 | outb_p(DEVICE_REGISTER,IO_INDEX_PORT); | ||
270 | outb_p(0x08,IO_DATA_PORT); | ||
271 | outb_p(0xF4,IO_INDEX_PORT); | ||
272 | new_status = inb_p(IO_DATA_PORT); | ||
273 | |||
274 | /* Lock the SuperIO chip */ | ||
275 | outb_p(LOCK_DATA,IO_INDEX_PORT); | ||
276 | |||
277 | spin_unlock_irqrestore(&spinlock, flags); | ||
278 | |||
279 | *status = 0; | ||
280 | if (new_status & 1) | ||
281 | *status |= WDIOF_CARDRESET; | ||
282 | |||
283 | return 0; | ||
284 | } | ||
285 | |||
286 | |||
287 | /* | ||
288 | * /dev/watchdog handling | ||
289 | */ | ||
290 | |||
291 | static int wdt_open(struct inode *inode, struct file *file) | ||
292 | { | ||
293 | /* If the watchdog is alive we don't need to start it again */ | ||
294 | if( test_and_set_bit(0, &timer_alive) ) | ||
295 | return -EBUSY; | ||
296 | |||
297 | if (nowayout) | ||
298 | __module_get(THIS_MODULE); | ||
299 | |||
300 | wdt_start(); | ||
301 | return nonseekable_open(inode, file); | ||
302 | } | ||
303 | |||
304 | static int wdt_release(struct inode *inode, struct file *file) | ||
305 | { | ||
306 | /* | ||
307 | * Shut off the timer. | ||
308 | * Lock it in if it's a module and we set nowayout | ||
309 | */ | ||
310 | if (expect_close == 42) | ||
311 | { | ||
312 | wdt_stop(); | ||
313 | clear_bit(0, &timer_alive); | ||
314 | } else { | ||
315 | wdt_keepalive(); | ||
316 | printk(KERN_CRIT PFX "unexpected close, not stopping watchdog!\n"); | ||
317 | } | ||
318 | expect_close = 0; | ||
319 | return 0; | ||
320 | } | ||
321 | |||
322 | /* | ||
323 | * wdt_write: | ||
324 | * @file: file handle to the watchdog | ||
325 | * @buf: buffer to write (unused as data does not matter here | ||
326 | * @count: count of bytes | ||
327 | * @ppos: pointer to the position to write. No seeks allowed | ||
328 | * | ||
329 | * A write to a watchdog device is defined as a keepalive signal. Any | ||
330 | * write of data will do, as we we don't define content meaning. | ||
331 | */ | ||
332 | |||
333 | static ssize_t wdt_write(struct file *file, const char __user *buf, | ||
334 | size_t count, loff_t *ppos) | ||
335 | { | ||
336 | /* See if we got the magic character 'V' and reload the timer */ | ||
337 | if(count) | ||
338 | { | ||
339 | if (!nowayout) | ||
340 | { | ||
341 | size_t ofs; | ||
342 | |||
343 | /* note: just in case someone wrote the magic character long ago */ | ||
344 | expect_close = 0; | ||
345 | |||
346 | /* scan to see whether or not we got the magic character */ | ||
347 | for(ofs = 0; ofs != count; ofs++) | ||
348 | { | ||
349 | char c; | ||
350 | if (get_user(c, buf + ofs)) | ||
351 | return -EFAULT; | ||
352 | if (c == 'V') { | ||
353 | expect_close = 42; | ||
354 | } | ||
355 | } | ||
356 | } | ||
357 | |||
358 | /* someone wrote to us, we should restart timer */ | ||
359 | wdt_keepalive(); | ||
360 | } | ||
361 | return count; | ||
362 | } | ||
363 | |||
364 | /* | ||
365 | * wdt_ioctl: | ||
366 | * @inode: inode of the device | ||
367 | * @file: file handle to the device | ||
368 | * @cmd: watchdog command | ||
369 | * @arg: argument pointer | ||
370 | * | ||
371 | * The watchdog API defines a common set of functions for all watchdogs | ||
372 | * according to their available features. | ||
373 | */ | ||
374 | |||
375 | static struct watchdog_info ident = { | ||
376 | .options = WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE | WDIOF_KEEPALIVEPING, | ||
377 | .firmware_version = 1, | ||
378 | .identity = WATCHDOG_NAME, | ||
379 | }; | ||
380 | |||
381 | static int wdt_ioctl(struct inode *inode, struct file *file, | ||
382 | unsigned int cmd, unsigned long arg) | ||
383 | { | ||
384 | int status; | ||
385 | int new_options, retval = -EINVAL; | ||
386 | int new_timeout; | ||
387 | union { | ||
388 | struct watchdog_info __user *ident; | ||
389 | int __user *i; | ||
390 | } uarg; | ||
391 | |||
392 | uarg.i = (int __user *)arg; | ||
393 | |||
394 | switch(cmd) | ||
395 | { | ||
396 | default: | ||
397 | return -ENOIOCTLCMD; | ||
398 | |||
399 | case WDIOC_GETSUPPORT: | ||
400 | return copy_to_user(uarg.ident, &ident, sizeof(ident)) ? -EFAULT : 0; | ||
401 | |||
402 | case WDIOC_GETSTATUS: | ||
403 | wdt_get_status(&status); | ||
404 | return put_user(status, uarg.i); | ||
405 | |||
406 | case WDIOC_GETBOOTSTATUS: | ||
407 | return put_user(0, uarg.i); | ||
408 | |||
409 | case WDIOC_KEEPALIVE: | ||
410 | wdt_keepalive(); | ||
411 | return 0; | ||
412 | |||
413 | case WDIOC_SETOPTIONS: | ||
414 | if (get_user (new_options, uarg.i)) | ||
415 | return -EFAULT; | ||
416 | |||
417 | if (new_options & WDIOS_DISABLECARD) { | ||
418 | wdt_stop(); | ||
419 | retval = 0; | ||
420 | } | ||
421 | |||
422 | if (new_options & WDIOS_ENABLECARD) { | ||
423 | wdt_start(); | ||
424 | retval = 0; | ||
425 | } | ||
426 | |||
427 | return retval; | ||
428 | |||
429 | case WDIOC_SETTIMEOUT: | ||
430 | if (get_user(new_timeout, uarg.i)) | ||
431 | return -EFAULT; | ||
432 | |||
433 | if (wdt_set_timeout(new_timeout)) | ||
434 | return -EINVAL; | ||
435 | |||
436 | wdt_keepalive(); | ||
437 | /* Fall */ | ||
438 | |||
439 | case WDIOC_GETTIMEOUT: | ||
440 | return put_user(timeout, uarg.i); | ||
441 | |||
442 | } | ||
443 | } | ||
444 | |||
445 | static int wdt_notify_sys(struct notifier_block *this, unsigned long code, | ||
446 | void *unused) | ||
447 | { | ||
448 | if (code==SYS_DOWN || code==SYS_HALT) | ||
449 | wdt_stop(); | ||
450 | return NOTIFY_DONE; | ||
451 | } | ||
452 | |||
453 | static struct file_operations wdt_fops= | ||
454 | { | ||
455 | .owner = THIS_MODULE, | ||
456 | .llseek = no_llseek, | ||
457 | .write = wdt_write, | ||
458 | .ioctl = wdt_ioctl, | ||
459 | .open = wdt_open, | ||
460 | .release = wdt_release, | ||
461 | }; | ||
462 | |||
463 | static struct miscdevice wdt_miscdev= | ||
464 | { | ||
465 | .minor = WATCHDOG_MINOR, | ||
466 | .name = "watchdog", | ||
467 | .fops = &wdt_fops, | ||
468 | }; | ||
469 | |||
470 | static struct notifier_block wdt_notifier = { | ||
471 | .notifier_call = wdt_notify_sys, | ||
472 | }; | ||
473 | |||
474 | static int __init w83977f_wdt_init(void) | ||
475 | { | ||
476 | int rc; | ||
477 | |||
478 | printk(KERN_INFO PFX DRIVER_VERSION); | ||
479 | |||
480 | spin_lock_init(&spinlock); | ||
481 | |||
482 | /* | ||
483 | * Check that the timeout value is within it's range ; | ||
484 | * if not reset to the default | ||
485 | */ | ||
486 | if (wdt_set_timeout(timeout)) { | ||
487 | wdt_set_timeout(DEFAULT_TIMEOUT); | ||
488 | printk(KERN_INFO PFX "timeout value must be 15<=timeout<=7635, using %d\n", | ||
489 | DEFAULT_TIMEOUT); | ||
490 | } | ||
491 | |||
492 | if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME)) | ||
493 | { | ||
494 | printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", | ||
495 | IO_INDEX_PORT); | ||
496 | rc = -EIO; | ||
497 | goto err_out; | ||
498 | } | ||
499 | |||
500 | rc = misc_register(&wdt_miscdev); | ||
501 | if (rc) | ||
502 | { | ||
503 | printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | ||
504 | wdt_miscdev.minor, rc); | ||
505 | goto err_out_region; | ||
506 | } | ||
507 | |||
508 | rc = register_reboot_notifier(&wdt_notifier); | ||
509 | if (rc) | ||
510 | { | ||
511 | printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", | ||
512 | rc); | ||
513 | goto err_out_miscdev; | ||
514 | } | ||
515 | |||
516 | printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d testmode=%d)\n", | ||
517 | timeout, nowayout, testmode); | ||
518 | |||
519 | return 0; | ||
520 | |||
521 | err_out_miscdev: | ||
522 | misc_deregister(&wdt_miscdev); | ||
523 | err_out_region: | ||
524 | release_region(IO_INDEX_PORT,2); | ||
525 | err_out: | ||
526 | return rc; | ||
527 | } | ||
528 | |||
529 | static void __exit w83977f_wdt_exit(void) | ||
530 | { | ||
531 | wdt_stop(); | ||
532 | misc_deregister(&wdt_miscdev); | ||
533 | unregister_reboot_notifier(&wdt_notifier); | ||
534 | release_region(IO_INDEX_PORT,2); | ||
535 | } | ||
536 | |||
537 | module_init(w83977f_wdt_init); | ||
538 | module_exit(w83977f_wdt_exit); | ||
539 | |||
540 | MODULE_AUTHOR("Jose Goncalves <jose.goncalves@inov.pt>"); | ||
541 | MODULE_DESCRIPTION("Driver for watchdog timer in W83977F I/O chip"); | ||
542 | MODULE_LICENSE("GPL"); | ||
543 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||