diff options
Diffstat (limited to 'drivers/watchdog/eurotechwdt.c')
-rw-r--r-- | drivers/watchdog/eurotechwdt.c | 473 |
1 files changed, 473 insertions, 0 deletions
diff --git a/drivers/watchdog/eurotechwdt.c b/drivers/watchdog/eurotechwdt.c new file mode 100644 index 000000000000..b14e9d1f164d --- /dev/null +++ b/drivers/watchdog/eurotechwdt.c | |||
@@ -0,0 +1,473 @@ | |||
1 | /* | ||
2 | * Eurotech CPU-1220/1410/1420 on board WDT driver | ||
3 | * | ||
4 | * (c) Copyright 2001 Ascensit <support@ascensit.com> | ||
5 | * (c) Copyright 2001 Rodolfo Giometti <giometti@ascensit.com> | ||
6 | * (c) Copyright 2002 Rob Radez <rob@osinvestor.com> | ||
7 | * | ||
8 | * Based on wdt.c. | ||
9 | * Original copyright messages: | ||
10 | * | ||
11 | * (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved. | ||
12 | * http://www.redhat.com | ||
13 | * | ||
14 | * This program is free software; you can redistribute it and/or | ||
15 | * modify it under the terms of the GNU General Public License | ||
16 | * as published by the Free Software Foundation; either version | ||
17 | * 2 of the License, or (at your option) any later version. | ||
18 | * | ||
19 | * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide | ||
20 | * warranty for any of this software. This material is provided | ||
21 | * "AS-IS" and at no charge. | ||
22 | * | ||
23 | * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>* | ||
24 | */ | ||
25 | |||
26 | /* Changelog: | ||
27 | * | ||
28 | * 2001 - Rodolfo Giometti | ||
29 | * Initial release | ||
30 | * | ||
31 | * 2002/04/25 - Rob Radez | ||
32 | * clean up #includes | ||
33 | * clean up locking | ||
34 | * make __setup param unique | ||
35 | * proper options in watchdog_info | ||
36 | * add WDIOC_GETSTATUS and WDIOC_SETOPTIONS ioctls | ||
37 | * add expect_close support | ||
38 | * | ||
39 | * 2002.05.30 - Joel Becker <joel.becker@oracle.com> | ||
40 | * Added Matt Domsch's nowayout module option. | ||
41 | */ | ||
42 | |||
43 | /* | ||
44 | * The eurotech CPU-1220/1410/1420's watchdog is a part | ||
45 | * of the on-board SUPER I/O device SMSC FDC 37B782. | ||
46 | */ | ||
47 | |||
48 | #include <linux/interrupt.h> | ||
49 | #include <linux/module.h> | ||
50 | #include <linux/moduleparam.h> | ||
51 | #include <linux/types.h> | ||
52 | #include <linux/miscdevice.h> | ||
53 | #include <linux/watchdog.h> | ||
54 | #include <linux/fs.h> | ||
55 | #include <linux/ioport.h> | ||
56 | #include <linux/notifier.h> | ||
57 | #include <linux/reboot.h> | ||
58 | #include <linux/init.h> | ||
59 | |||
60 | #include <asm/io.h> | ||
61 | #include <asm/uaccess.h> | ||
62 | #include <asm/system.h> | ||
63 | |||
64 | static unsigned long eurwdt_is_open; | ||
65 | static int eurwdt_timeout; | ||
66 | static char eur_expect_close; | ||
67 | |||
68 | /* | ||
69 | * You must set these - there is no sane way to probe for this board. | ||
70 | * You can use eurwdt=x,y to set these now. | ||
71 | */ | ||
72 | |||
73 | static int io = 0x3f0; | ||
74 | static int irq = 10; | ||
75 | static char *ev = "int"; | ||
76 | |||
77 | #define WDT_TIMEOUT 60 /* 1 minute */ | ||
78 | |||
79 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
80 | module_param(nowayout, int, 0); | ||
81 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | ||
82 | |||
83 | /* | ||
84 | * Some symbolic names | ||
85 | */ | ||
86 | |||
87 | #define WDT_CTRL_REG 0x30 | ||
88 | #define WDT_OUTPIN_CFG 0xe2 | ||
89 | #define WDT_EVENT_INT 0x00 | ||
90 | #define WDT_EVENT_REBOOT 0x08 | ||
91 | #define WDT_UNIT_SEL 0xf1 | ||
92 | #define WDT_UNIT_SECS 0x80 | ||
93 | #define WDT_TIMEOUT_VAL 0xf2 | ||
94 | #define WDT_TIMER_CFG 0xf3 | ||
95 | |||
96 | |||
97 | module_param(io, int, 0); | ||
98 | MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)"); | ||
99 | module_param(irq, int, 0); | ||
100 | MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)"); | ||
101 | module_param(ev, charp, 0); | ||
102 | MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')"); | ||
103 | |||
104 | |||
105 | /* | ||
106 | * Programming support | ||
107 | */ | ||
108 | |||
109 | static inline void eurwdt_write_reg(u8 index, u8 data) | ||
110 | { | ||
111 | outb(index, io); | ||
112 | outb(data, io+1); | ||
113 | } | ||
114 | |||
115 | static inline void eurwdt_lock_chip(void) | ||
116 | { | ||
117 | outb(0xaa, io); | ||
118 | } | ||
119 | |||
120 | static inline void eurwdt_unlock_chip(void) | ||
121 | { | ||
122 | outb(0x55, io); | ||
123 | eurwdt_write_reg(0x07, 0x08); /* set the logical device */ | ||
124 | } | ||
125 | |||
126 | static inline void eurwdt_set_timeout(int timeout) | ||
127 | { | ||
128 | eurwdt_write_reg(WDT_TIMEOUT_VAL, (u8) timeout); | ||
129 | } | ||
130 | |||
131 | static inline void eurwdt_disable_timer(void) | ||
132 | { | ||
133 | eurwdt_set_timeout(0); | ||
134 | } | ||
135 | |||
136 | static void eurwdt_activate_timer(void) | ||
137 | { | ||
138 | eurwdt_disable_timer(); | ||
139 | eurwdt_write_reg(WDT_CTRL_REG, 0x01); /* activate the WDT */ | ||
140 | eurwdt_write_reg(WDT_OUTPIN_CFG, !strcmp("int", ev) ? WDT_EVENT_INT : WDT_EVENT_REBOOT); | ||
141 | |||
142 | /* Setting interrupt line */ | ||
143 | if (irq == 2 || irq > 15 || irq < 0) { | ||
144 | printk(KERN_ERR ": invalid irq number\n"); | ||
145 | irq = 0; /* if invalid we disable interrupt */ | ||
146 | } | ||
147 | if (irq == 0) | ||
148 | printk(KERN_INFO ": interrupt disabled\n"); | ||
149 | |||
150 | eurwdt_write_reg(WDT_TIMER_CFG, irq<<4); | ||
151 | |||
152 | eurwdt_write_reg(WDT_UNIT_SEL, WDT_UNIT_SECS); /* we use seconds */ | ||
153 | eurwdt_set_timeout(0); /* the default timeout */ | ||
154 | } | ||
155 | |||
156 | |||
157 | /* | ||
158 | * Kernel methods. | ||
159 | */ | ||
160 | |||
161 | static irqreturn_t eurwdt_interrupt(int irq, void *dev_id) | ||
162 | { | ||
163 | printk(KERN_CRIT "timeout WDT timeout\n"); | ||
164 | |||
165 | #ifdef ONLY_TESTING | ||
166 | printk(KERN_CRIT "Would Reboot.\n"); | ||
167 | #else | ||
168 | printk(KERN_CRIT "Initiating system reboot.\n"); | ||
169 | emergency_restart(); | ||
170 | #endif | ||
171 | return IRQ_HANDLED; | ||
172 | } | ||
173 | |||
174 | |||
175 | /** | ||
176 | * eurwdt_ping: | ||
177 | * | ||
178 | * Reload counter one with the watchdog timeout. | ||
179 | */ | ||
180 | |||
181 | static void eurwdt_ping(void) | ||
182 | { | ||
183 | /* Write the watchdog default value */ | ||
184 | eurwdt_set_timeout(eurwdt_timeout); | ||
185 | } | ||
186 | |||
187 | /** | ||
188 | * eurwdt_write: | ||
189 | * @file: file handle to the watchdog | ||
190 | * @buf: buffer to write (unused as data does not matter here | ||
191 | * @count: count of bytes | ||
192 | * @ppos: pointer to the position to write. No seeks allowed | ||
193 | * | ||
194 | * A write to a watchdog device is defined as a keepalive signal. Any | ||
195 | * write of data will do, as we we don't define content meaning. | ||
196 | */ | ||
197 | |||
198 | static ssize_t eurwdt_write(struct file *file, const char __user *buf, | ||
199 | size_t count, loff_t *ppos) | ||
200 | { | ||
201 | if (count) { | ||
202 | if (!nowayout) { | ||
203 | size_t i; | ||
204 | |||
205 | eur_expect_close = 0; | ||
206 | |||
207 | for (i = 0; i != count; i++) { | ||
208 | char c; | ||
209 | if(get_user(c, buf+i)) | ||
210 | return -EFAULT; | ||
211 | if (c == 'V') | ||
212 | eur_expect_close = 42; | ||
213 | } | ||
214 | } | ||
215 | eurwdt_ping(); /* the default timeout */ | ||
216 | } | ||
217 | |||
218 | return count; | ||
219 | } | ||
220 | |||
221 | /** | ||
222 | * eurwdt_ioctl: | ||
223 | * @inode: inode of the device | ||
224 | * @file: file handle to the device | ||
225 | * @cmd: watchdog command | ||
226 | * @arg: argument pointer | ||
227 | * | ||
228 | * The watchdog API defines a common set of functions for all watchdogs | ||
229 | * according to their available features. | ||
230 | */ | ||
231 | |||
232 | static int eurwdt_ioctl(struct inode *inode, struct file *file, | ||
233 | unsigned int cmd, unsigned long arg) | ||
234 | { | ||
235 | void __user *argp = (void __user *)arg; | ||
236 | int __user *p = argp; | ||
237 | static struct watchdog_info ident = { | ||
238 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, | ||
239 | .firmware_version = 1, | ||
240 | .identity = "WDT Eurotech CPU-1220/1410", | ||
241 | }; | ||
242 | |||
243 | int time; | ||
244 | int options, retval = -EINVAL; | ||
245 | |||
246 | switch(cmd) { | ||
247 | default: | ||
248 | return -ENOTTY; | ||
249 | |||
250 | case WDIOC_GETSUPPORT: | ||
251 | return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; | ||
252 | |||
253 | case WDIOC_GETSTATUS: | ||
254 | case WDIOC_GETBOOTSTATUS: | ||
255 | return put_user(0, p); | ||
256 | |||
257 | case WDIOC_KEEPALIVE: | ||
258 | eurwdt_ping(); | ||
259 | return 0; | ||
260 | |||
261 | case WDIOC_SETTIMEOUT: | ||
262 | if (copy_from_user(&time, p, sizeof(int))) | ||
263 | return -EFAULT; | ||
264 | |||
265 | /* Sanity check */ | ||
266 | if (time < 0 || time > 255) | ||
267 | return -EINVAL; | ||
268 | |||
269 | eurwdt_timeout = time; | ||
270 | eurwdt_set_timeout(time); | ||
271 | /* Fall */ | ||
272 | |||
273 | case WDIOC_GETTIMEOUT: | ||
274 | return put_user(eurwdt_timeout, p); | ||
275 | |||
276 | case WDIOC_SETOPTIONS: | ||
277 | if (get_user(options, p)) | ||
278 | return -EFAULT; | ||
279 | if (options & WDIOS_DISABLECARD) { | ||
280 | eurwdt_disable_timer(); | ||
281 | retval = 0; | ||
282 | } | ||
283 | if (options & WDIOS_ENABLECARD) { | ||
284 | eurwdt_activate_timer(); | ||
285 | eurwdt_ping(); | ||
286 | retval = 0; | ||
287 | } | ||
288 | return retval; | ||
289 | } | ||
290 | } | ||
291 | |||
292 | /** | ||
293 | * eurwdt_open: | ||
294 | * @inode: inode of device | ||
295 | * @file: file handle to device | ||
296 | * | ||
297 | * The misc device has been opened. The watchdog device is single | ||
298 | * open and on opening we load the counter. | ||
299 | */ | ||
300 | |||
301 | static int eurwdt_open(struct inode *inode, struct file *file) | ||
302 | { | ||
303 | if (test_and_set_bit(0, &eurwdt_is_open)) | ||
304 | return -EBUSY; | ||
305 | eurwdt_timeout = WDT_TIMEOUT; /* initial timeout */ | ||
306 | /* Activate the WDT */ | ||
307 | eurwdt_activate_timer(); | ||
308 | return nonseekable_open(inode, file); | ||
309 | } | ||
310 | |||
311 | /** | ||
312 | * eurwdt_release: | ||
313 | * @inode: inode to board | ||
314 | * @file: file handle to board | ||
315 | * | ||
316 | * The watchdog has a configurable API. There is a religious dispute | ||
317 | * between people who want their watchdog to be able to shut down and | ||
318 | * those who want to be sure if the watchdog manager dies the machine | ||
319 | * reboots. In the former case we disable the counters, in the latter | ||
320 | * case you have to open it again very soon. | ||
321 | */ | ||
322 | |||
323 | static int eurwdt_release(struct inode *inode, struct file *file) | ||
324 | { | ||
325 | if (eur_expect_close == 42) { | ||
326 | eurwdt_disable_timer(); | ||
327 | } else { | ||
328 | printk(KERN_CRIT "eurwdt: Unexpected close, not stopping watchdog!\n"); | ||
329 | eurwdt_ping(); | ||
330 | } | ||
331 | clear_bit(0, &eurwdt_is_open); | ||
332 | eur_expect_close = 0; | ||
333 | return 0; | ||
334 | } | ||
335 | |||
336 | /** | ||
337 | * eurwdt_notify_sys: | ||
338 | * @this: our notifier block | ||
339 | * @code: the event being reported | ||
340 | * @unused: unused | ||
341 | * | ||
342 | * Our notifier is called on system shutdowns. We want to turn the card | ||
343 | * off at reboot otherwise the machine will reboot again during memory | ||
344 | * test or worse yet during the following fsck. This would suck, in fact | ||
345 | * trust me - if it happens it does suck. | ||
346 | */ | ||
347 | |||
348 | static int eurwdt_notify_sys(struct notifier_block *this, unsigned long code, | ||
349 | void *unused) | ||
350 | { | ||
351 | if (code == SYS_DOWN || code == SYS_HALT) { | ||
352 | /* Turn the card off */ | ||
353 | eurwdt_disable_timer(); | ||
354 | } | ||
355 | |||
356 | return NOTIFY_DONE; | ||
357 | } | ||
358 | |||
359 | /* | ||
360 | * Kernel Interfaces | ||
361 | */ | ||
362 | |||
363 | |||
364 | static const struct file_operations eurwdt_fops = { | ||
365 | .owner = THIS_MODULE, | ||
366 | .llseek = no_llseek, | ||
367 | .write = eurwdt_write, | ||
368 | .ioctl = eurwdt_ioctl, | ||
369 | .open = eurwdt_open, | ||
370 | .release = eurwdt_release, | ||
371 | }; | ||
372 | |||
373 | static struct miscdevice eurwdt_miscdev = { | ||
374 | .minor = WATCHDOG_MINOR, | ||
375 | .name = "watchdog", | ||
376 | .fops = &eurwdt_fops, | ||
377 | }; | ||
378 | |||
379 | /* | ||
380 | * The WDT card needs to learn about soft shutdowns in order to | ||
381 | * turn the timebomb registers off. | ||
382 | */ | ||
383 | |||
384 | static struct notifier_block eurwdt_notifier = { | ||
385 | .notifier_call = eurwdt_notify_sys, | ||
386 | }; | ||
387 | |||
388 | /** | ||
389 | * cleanup_module: | ||
390 | * | ||
391 | * Unload the watchdog. You cannot do this with any file handles open. | ||
392 | * If your watchdog is set to continue ticking on close and you unload | ||
393 | * it, well it keeps ticking. We won't get the interrupt but the board | ||
394 | * will not touch PC memory so all is fine. You just have to load a new | ||
395 | * module in 60 seconds or reboot. | ||
396 | */ | ||
397 | |||
398 | static void __exit eurwdt_exit(void) | ||
399 | { | ||
400 | eurwdt_lock_chip(); | ||
401 | |||
402 | misc_deregister(&eurwdt_miscdev); | ||
403 | |||
404 | unregister_reboot_notifier(&eurwdt_notifier); | ||
405 | release_region(io, 2); | ||
406 | free_irq(irq, NULL); | ||
407 | } | ||
408 | |||
409 | /** | ||
410 | * eurwdt_init: | ||
411 | * | ||
412 | * Set up the WDT watchdog board. After grabbing the resources | ||
413 | * we require we need also to unlock the device. | ||
414 | * The open() function will actually kick the board off. | ||
415 | */ | ||
416 | |||
417 | static int __init eurwdt_init(void) | ||
418 | { | ||
419 | int ret; | ||
420 | |||
421 | ret = request_irq(irq, eurwdt_interrupt, IRQF_DISABLED, "eurwdt", NULL); | ||
422 | if(ret) { | ||
423 | printk(KERN_ERR "eurwdt: IRQ %d is not free.\n", irq); | ||
424 | goto out; | ||
425 | } | ||
426 | |||
427 | if (!request_region(io, 2, "eurwdt")) { | ||
428 | printk(KERN_ERR "eurwdt: IO %X is not free.\n", io); | ||
429 | ret = -EBUSY; | ||
430 | goto outirq; | ||
431 | } | ||
432 | |||
433 | ret = register_reboot_notifier(&eurwdt_notifier); | ||
434 | if (ret) { | ||
435 | printk(KERN_ERR "eurwdt: can't register reboot notifier (err=%d)\n", ret); | ||
436 | goto outreg; | ||
437 | } | ||
438 | |||
439 | ret = misc_register(&eurwdt_miscdev); | ||
440 | if (ret) { | ||
441 | printk(KERN_ERR "eurwdt: can't misc_register on minor=%d\n", | ||
442 | WATCHDOG_MINOR); | ||
443 | goto outreboot; | ||
444 | } | ||
445 | |||
446 | eurwdt_unlock_chip(); | ||
447 | |||
448 | ret = 0; | ||
449 | printk(KERN_INFO "Eurotech WDT driver 0.01 at %X (Interrupt %d)" | ||
450 | " - timeout event: %s\n", | ||
451 | io, irq, (!strcmp("int", ev) ? "int" : "reboot")); | ||
452 | |||
453 | out: | ||
454 | return ret; | ||
455 | |||
456 | outreboot: | ||
457 | unregister_reboot_notifier(&eurwdt_notifier); | ||
458 | |||
459 | outreg: | ||
460 | release_region(io, 2); | ||
461 | |||
462 | outirq: | ||
463 | free_irq(irq, NULL); | ||
464 | goto out; | ||
465 | } | ||
466 | |||
467 | module_init(eurwdt_init); | ||
468 | module_exit(eurwdt_exit); | ||
469 | |||
470 | MODULE_AUTHOR("Rodolfo Giometti"); | ||
471 | MODULE_DESCRIPTION("Driver for Eurotech CPU-1220/1410 on board watchdog"); | ||
472 | MODULE_LICENSE("GPL"); | ||
473 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||