Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
0f112a86 | 2 | * Eurotech CPU-1220/1410/1420 on board WDT driver |
1da177e4 LT |
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 | * | |
143a2e54 | 11 | * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>, |
29fa0586 | 12 | * All Rights Reserved. |
1da177e4 | 13 | * |
143a2e54 WVS |
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. | |
1da177e4 | 18 | * |
143a2e54 WVS |
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. | |
1da177e4 | 22 | * |
143a2e54 | 23 | * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>* |
1da177e4 LT |
24 | */ |
25 | ||
26 | /* Changelog: | |
0f112a86 WVS |
27 | * |
28 | * 2001 - Rodolfo Giometti | |
29 | * Initial release | |
1da177e4 LT |
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 | * | |
1da177e4 | 39 | * 2002.05.30 - Joel Becker <joel.becker@oracle.com> |
143a2e54 | 40 | * Added Matt Domsch's nowayout module option. |
1da177e4 LT |
41 | */ |
42 | ||
0f112a86 WVS |
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 | ||
27c766aa JP |
48 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
49 | ||
1da177e4 LT |
50 | #include <linux/interrupt.h> |
51 | #include <linux/module.h> | |
52 | #include <linux/moduleparam.h> | |
53 | #include <linux/types.h> | |
54 | #include <linux/miscdevice.h> | |
55 | #include <linux/watchdog.h> | |
56 | #include <linux/fs.h> | |
57 | #include <linux/ioport.h> | |
58 | #include <linux/notifier.h> | |
59 | #include <linux/reboot.h> | |
60 | #include <linux/init.h> | |
89ea2429 AC |
61 | #include <linux/io.h> |
62 | #include <linux/uaccess.h> | |
1da177e4 | 63 | |
1da177e4 LT |
64 | |
65 | static unsigned long eurwdt_is_open; | |
66 | static int eurwdt_timeout; | |
67 | static char eur_expect_close; | |
1334f329 | 68 | static DEFINE_SPINLOCK(eurwdt_lock); |
1da177e4 LT |
69 | |
70 | /* | |
71 | * You must set these - there is no sane way to probe for this board. | |
1da177e4 LT |
72 | */ |
73 | ||
74 | static int io = 0x3f0; | |
75 | static int irq = 10; | |
76 | static char *ev = "int"; | |
77 | ||
78 | #define WDT_TIMEOUT 60 /* 1 minute */ | |
79 | ||
86a1e189 WVS |
80 | static bool nowayout = WATCHDOG_NOWAYOUT; |
81 | module_param(nowayout, bool, 0); | |
89ea2429 AC |
82 | MODULE_PARM_DESC(nowayout, |
83 | "Watchdog cannot be stopped once started (default=" | |
84 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | |
1da177e4 LT |
85 | |
86 | /* | |
87 | * Some symbolic names | |
88 | */ | |
89 | ||
90 | #define WDT_CTRL_REG 0x30 | |
91 | #define WDT_OUTPIN_CFG 0xe2 | |
92 | #define WDT_EVENT_INT 0x00 | |
93 | #define WDT_EVENT_REBOOT 0x08 | |
94 | #define WDT_UNIT_SEL 0xf1 | |
95 | #define WDT_UNIT_SECS 0x80 | |
96 | #define WDT_TIMEOUT_VAL 0xf2 | |
97 | #define WDT_TIMER_CFG 0xf3 | |
98 | ||
99 | ||
100 | module_param(io, int, 0); | |
101 | MODULE_PARM_DESC(io, "Eurotech WDT io port (default=0x3f0)"); | |
102 | module_param(irq, int, 0); | |
103 | MODULE_PARM_DESC(irq, "Eurotech WDT irq (default=10)"); | |
104 | module_param(ev, charp, 0); | |
105 | MODULE_PARM_DESC(ev, "Eurotech WDT event type (default is `int')"); | |
106 | ||
107 | ||
108 | /* | |
109 | * Programming support | |
110 | */ | |
111 | ||
112 | static inline void eurwdt_write_reg(u8 index, u8 data) | |
113 | { | |
114 | outb(index, io); | |
115 | outb(data, io+1); | |
116 | } | |
117 | ||
118 | static inline void eurwdt_lock_chip(void) | |
119 | { | |
120 | outb(0xaa, io); | |
121 | } | |
122 | ||
123 | static inline void eurwdt_unlock_chip(void) | |
124 | { | |
125 | outb(0x55, io); | |
126 | eurwdt_write_reg(0x07, 0x08); /* set the logical device */ | |
127 | } | |
128 | ||
129 | static inline void eurwdt_set_timeout(int timeout) | |
130 | { | |
131 | eurwdt_write_reg(WDT_TIMEOUT_VAL, (u8) timeout); | |
132 | } | |
133 | ||
134 | static inline void eurwdt_disable_timer(void) | |
135 | { | |
136 | eurwdt_set_timeout(0); | |
137 | } | |
138 | ||
139 | static void eurwdt_activate_timer(void) | |
140 | { | |
141 | eurwdt_disable_timer(); | |
142 | eurwdt_write_reg(WDT_CTRL_REG, 0x01); /* activate the WDT */ | |
89ea2429 AC |
143 | eurwdt_write_reg(WDT_OUTPIN_CFG, |
144 | !strcmp("int", ev) ? WDT_EVENT_INT : WDT_EVENT_REBOOT); | |
1da177e4 LT |
145 | |
146 | /* Setting interrupt line */ | |
147 | if (irq == 2 || irq > 15 || irq < 0) { | |
27c766aa | 148 | pr_err("invalid irq number\n"); |
1da177e4 LT |
149 | irq = 0; /* if invalid we disable interrupt */ |
150 | } | |
151 | if (irq == 0) | |
27c766aa | 152 | pr_info("interrupt disabled\n"); |
1da177e4 | 153 | |
143a2e54 | 154 | eurwdt_write_reg(WDT_TIMER_CFG, irq << 4); |
1da177e4 LT |
155 | |
156 | eurwdt_write_reg(WDT_UNIT_SEL, WDT_UNIT_SECS); /* we use seconds */ | |
157 | eurwdt_set_timeout(0); /* the default timeout */ | |
158 | } | |
159 | ||
160 | ||
161 | /* | |
162 | * Kernel methods. | |
163 | */ | |
164 | ||
7d12e780 | 165 | static irqreturn_t eurwdt_interrupt(int irq, void *dev_id) |
1da177e4 | 166 | { |
27c766aa | 167 | pr_crit("timeout WDT timeout\n"); |
1da177e4 LT |
168 | |
169 | #ifdef ONLY_TESTING | |
27c766aa | 170 | pr_crit("Would Reboot\n"); |
1da177e4 | 171 | #else |
27c766aa | 172 | pr_crit("Initiating system reboot\n"); |
cc1d3a9a | 173 | emergency_restart(); |
1da177e4 LT |
174 | #endif |
175 | return IRQ_HANDLED; | |
176 | } | |
177 | ||
178 | ||
179 | /** | |
180 | * eurwdt_ping: | |
181 | * | |
182 | * Reload counter one with the watchdog timeout. | |
183 | */ | |
184 | ||
185 | static void eurwdt_ping(void) | |
186 | { | |
187 | /* Write the watchdog default value */ | |
188 | eurwdt_set_timeout(eurwdt_timeout); | |
189 | } | |
190 | ||
191 | /** | |
192 | * eurwdt_write: | |
193 | * @file: file handle to the watchdog | |
194 | * @buf: buffer to write (unused as data does not matter here | |
195 | * @count: count of bytes | |
196 | * @ppos: pointer to the position to write. No seeks allowed | |
197 | * | |
198 | * A write to a watchdog device is defined as a keepalive signal. Any | |
199 | * write of data will do, as we we don't define content meaning. | |
200 | */ | |
201 | ||
202 | static ssize_t eurwdt_write(struct file *file, const char __user *buf, | |
203 | size_t count, loff_t *ppos) | |
204 | { | |
5f3b2756 | 205 | if (count) { |
1da177e4 LT |
206 | if (!nowayout) { |
207 | size_t i; | |
208 | ||
209 | eur_expect_close = 0; | |
210 | ||
211 | for (i = 0; i != count; i++) { | |
212 | char c; | |
7944d3a5 | 213 | if (get_user(c, buf + i)) |
1da177e4 LT |
214 | return -EFAULT; |
215 | if (c == 'V') | |
216 | eur_expect_close = 42; | |
217 | } | |
218 | } | |
89ea2429 | 219 | spin_lock(&eurwdt_lock); |
1da177e4 | 220 | eurwdt_ping(); /* the default timeout */ |
89ea2429 | 221 | spin_unlock(&eurwdt_lock); |
1da177e4 | 222 | } |
1da177e4 LT |
223 | return count; |
224 | } | |
225 | ||
226 | /** | |
227 | * eurwdt_ioctl: | |
1da177e4 LT |
228 | * @file: file handle to the device |
229 | * @cmd: watchdog command | |
230 | * @arg: argument pointer | |
231 | * | |
232 | * The watchdog API defines a common set of functions for all watchdogs | |
233 | * according to their available features. | |
234 | */ | |
235 | ||
89ea2429 AC |
236 | static long eurwdt_ioctl(struct file *file, |
237 | unsigned int cmd, unsigned long arg) | |
1da177e4 LT |
238 | { |
239 | void __user *argp = (void __user *)arg; | |
240 | int __user *p = argp; | |
42747d71 | 241 | static const struct watchdog_info ident = { |
89ea2429 AC |
242 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT |
243 | | WDIOF_MAGICCLOSE, | |
1da177e4 LT |
244 | .firmware_version = 1, |
245 | .identity = "WDT Eurotech CPU-1220/1410", | |
246 | }; | |
247 | ||
248 | int time; | |
249 | int options, retval = -EINVAL; | |
250 | ||
89ea2429 | 251 | switch (cmd) { |
1da177e4 LT |
252 | case WDIOC_GETSUPPORT: |
253 | return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; | |
254 | ||
255 | case WDIOC_GETSTATUS: | |
256 | case WDIOC_GETBOOTSTATUS: | |
257 | return put_user(0, p); | |
258 | ||
0c06090c WVS |
259 | case WDIOC_SETOPTIONS: |
260 | if (get_user(options, p)) | |
261 | return -EFAULT; | |
262 | spin_lock(&eurwdt_lock); | |
263 | if (options & WDIOS_DISABLECARD) { | |
264 | eurwdt_disable_timer(); | |
265 | retval = 0; | |
266 | } | |
267 | if (options & WDIOS_ENABLECARD) { | |
268 | eurwdt_activate_timer(); | |
269 | eurwdt_ping(); | |
270 | retval = 0; | |
271 | } | |
272 | spin_unlock(&eurwdt_lock); | |
273 | return retval; | |
274 | ||
1da177e4 | 275 | case WDIOC_KEEPALIVE: |
89ea2429 | 276 | spin_lock(&eurwdt_lock); |
1da177e4 | 277 | eurwdt_ping(); |
89ea2429 | 278 | spin_unlock(&eurwdt_lock); |
1da177e4 LT |
279 | return 0; |
280 | ||
281 | case WDIOC_SETTIMEOUT: | |
282 | if (copy_from_user(&time, p, sizeof(int))) | |
283 | return -EFAULT; | |
284 | ||
285 | /* Sanity check */ | |
286 | if (time < 0 || time > 255) | |
287 | return -EINVAL; | |
288 | ||
89ea2429 | 289 | spin_lock(&eurwdt_lock); |
1da177e4 LT |
290 | eurwdt_timeout = time; |
291 | eurwdt_set_timeout(time); | |
89ea2429 | 292 | spin_unlock(&eurwdt_lock); |
1da177e4 LT |
293 | /* Fall */ |
294 | ||
295 | case WDIOC_GETTIMEOUT: | |
296 | return put_user(eurwdt_timeout, p); | |
297 | ||
0c06090c WVS |
298 | default: |
299 | return -ENOTTY; | |
1da177e4 LT |
300 | } |
301 | } | |
302 | ||
303 | /** | |
304 | * eurwdt_open: | |
305 | * @inode: inode of device | |
306 | * @file: file handle to device | |
307 | * | |
308 | * The misc device has been opened. The watchdog device is single | |
309 | * open and on opening we load the counter. | |
310 | */ | |
311 | ||
312 | static int eurwdt_open(struct inode *inode, struct file *file) | |
313 | { | |
314 | if (test_and_set_bit(0, &eurwdt_is_open)) | |
315 | return -EBUSY; | |
316 | eurwdt_timeout = WDT_TIMEOUT; /* initial timeout */ | |
317 | /* Activate the WDT */ | |
318 | eurwdt_activate_timer(); | |
319 | return nonseekable_open(inode, file); | |
320 | } | |
321 | ||
322 | /** | |
323 | * eurwdt_release: | |
324 | * @inode: inode to board | |
325 | * @file: file handle to board | |
326 | * | |
327 | * The watchdog has a configurable API. There is a religious dispute | |
328 | * between people who want their watchdog to be able to shut down and | |
329 | * those who want to be sure if the watchdog manager dies the machine | |
330 | * reboots. In the former case we disable the counters, in the latter | |
331 | * case you have to open it again very soon. | |
332 | */ | |
333 | ||
334 | static int eurwdt_release(struct inode *inode, struct file *file) | |
335 | { | |
89ea2429 | 336 | if (eur_expect_close == 42) |
1da177e4 | 337 | eurwdt_disable_timer(); |
89ea2429 | 338 | else { |
27c766aa | 339 | pr_crit("Unexpected close, not stopping watchdog!\n"); |
1da177e4 LT |
340 | eurwdt_ping(); |
341 | } | |
342 | clear_bit(0, &eurwdt_is_open); | |
343 | eur_expect_close = 0; | |
344 | return 0; | |
345 | } | |
346 | ||
347 | /** | |
348 | * eurwdt_notify_sys: | |
349 | * @this: our notifier block | |
350 | * @code: the event being reported | |
351 | * @unused: unused | |
352 | * | |
353 | * Our notifier is called on system shutdowns. We want to turn the card | |
354 | * off at reboot otherwise the machine will reboot again during memory | |
355 | * test or worse yet during the following fsck. This would suck, in fact | |
356 | * trust me - if it happens it does suck. | |
357 | */ | |
358 | ||
359 | static int eurwdt_notify_sys(struct notifier_block *this, unsigned long code, | |
360 | void *unused) | |
361 | { | |
7944d3a5 WVS |
362 | if (code == SYS_DOWN || code == SYS_HALT) |
363 | eurwdt_disable_timer(); /* Turn the card off */ | |
1da177e4 LT |
364 | |
365 | return NOTIFY_DONE; | |
366 | } | |
367 | ||
368 | /* | |
369 | * Kernel Interfaces | |
370 | */ | |
371 | ||
372 | ||
62322d25 | 373 | static const struct file_operations eurwdt_fops = { |
89ea2429 AC |
374 | .owner = THIS_MODULE, |
375 | .llseek = no_llseek, | |
376 | .write = eurwdt_write, | |
377 | .unlocked_ioctl = eurwdt_ioctl, | |
378 | .open = eurwdt_open, | |
1da177e4 LT |
379 | .release = eurwdt_release, |
380 | }; | |
381 | ||
382 | static struct miscdevice eurwdt_miscdev = { | |
383 | .minor = WATCHDOG_MINOR, | |
384 | .name = "watchdog", | |
385 | .fops = &eurwdt_fops, | |
386 | }; | |
387 | ||
388 | /* | |
389 | * The WDT card needs to learn about soft shutdowns in order to | |
390 | * turn the timebomb registers off. | |
391 | */ | |
392 | ||
393 | static struct notifier_block eurwdt_notifier = { | |
394 | .notifier_call = eurwdt_notify_sys, | |
395 | }; | |
396 | ||
397 | /** | |
398 | * cleanup_module: | |
399 | * | |
400 | * Unload the watchdog. You cannot do this with any file handles open. | |
401 | * If your watchdog is set to continue ticking on close and you unload | |
402 | * it, well it keeps ticking. We won't get the interrupt but the board | |
403 | * will not touch PC memory so all is fine. You just have to load a new | |
404 | * module in 60 seconds or reboot. | |
405 | */ | |
406 | ||
407 | static void __exit eurwdt_exit(void) | |
408 | { | |
409 | eurwdt_lock_chip(); | |
410 | ||
411 | misc_deregister(&eurwdt_miscdev); | |
412 | ||
413 | unregister_reboot_notifier(&eurwdt_notifier); | |
414 | release_region(io, 2); | |
415 | free_irq(irq, NULL); | |
416 | } | |
417 | ||
418 | /** | |
419 | * eurwdt_init: | |
420 | * | |
421 | * Set up the WDT watchdog board. After grabbing the resources | |
422 | * we require we need also to unlock the device. | |
423 | * The open() function will actually kick the board off. | |
424 | */ | |
425 | ||
426 | static int __init eurwdt_init(void) | |
427 | { | |
428 | int ret; | |
429 | ||
86b59128 | 430 | ret = request_irq(irq, eurwdt_interrupt, 0, "eurwdt", NULL); |
89ea2429 | 431 | if (ret) { |
27c766aa | 432 | pr_err("IRQ %d is not free\n", irq); |
fb8f7ba0 | 433 | goto out; |
1da177e4 LT |
434 | } |
435 | ||
436 | if (!request_region(io, 2, "eurwdt")) { | |
27c766aa | 437 | pr_err("IO %X is not free\n", io); |
1da177e4 LT |
438 | ret = -EBUSY; |
439 | goto outirq; | |
440 | } | |
441 | ||
442 | ret = register_reboot_notifier(&eurwdt_notifier); | |
443 | if (ret) { | |
27c766aa | 444 | pr_err("can't register reboot notifier (err=%d)\n", ret); |
1da177e4 LT |
445 | goto outreg; |
446 | } | |
447 | ||
fb8f7ba0 AD |
448 | ret = misc_register(&eurwdt_miscdev); |
449 | if (ret) { | |
27c766aa | 450 | pr_err("can't misc_register on minor=%d\n", WATCHDOG_MINOR); |
fb8f7ba0 AD |
451 | goto outreboot; |
452 | } | |
453 | ||
1da177e4 LT |
454 | eurwdt_unlock_chip(); |
455 | ||
456 | ret = 0; | |
27c766aa | 457 | pr_info("Eurotech WDT driver 0.01 at %X (Interrupt %d) - timeout event: %s\n", |
1da177e4 LT |
458 | io, irq, (!strcmp("int", ev) ? "int" : "reboot")); |
459 | ||
460 | out: | |
461 | return ret; | |
462 | ||
fb8f7ba0 AD |
463 | outreboot: |
464 | unregister_reboot_notifier(&eurwdt_notifier); | |
465 | ||
1da177e4 LT |
466 | outreg: |
467 | release_region(io, 2); | |
468 | ||
469 | outirq: | |
470 | free_irq(irq, NULL); | |
1da177e4 LT |
471 | goto out; |
472 | } | |
473 | ||
474 | module_init(eurwdt_init); | |
475 | module_exit(eurwdt_exit); | |
476 | ||
477 | MODULE_AUTHOR("Rodolfo Giometti"); | |
478 | MODULE_DESCRIPTION("Driver for Eurotech CPU-1220/1410 on board watchdog"); | |
479 | MODULE_LICENSE("GPL"); |