diff options
Diffstat (limited to 'drivers/char/watchdog/w83697hf_wdt.c')
-rw-r--r-- | drivers/char/watchdog/w83697hf_wdt.c | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/drivers/char/watchdog/w83697hf_wdt.c b/drivers/char/watchdog/w83697hf_wdt.c new file mode 100644 index 000000000000..7768b55487c8 --- /dev/null +++ b/drivers/char/watchdog/w83697hf_wdt.c | |||
@@ -0,0 +1,450 @@ | |||
1 | /* | ||
2 | * w83697hf/hg WDT driver | ||
3 | * | ||
4 | * (c) Copyright 2006 Samuel Tardieu <sam@rfc1149.net> | ||
5 | * (c) Copyright 2006 Marcus Junker <junker@anduras.de> | ||
6 | * | ||
7 | * Based on w83627hf_wdt.c which is based on advantechwdt.c | ||
8 | * which is based on wdt.c. | ||
9 | * Original copyright messages: | ||
10 | * | ||
11 | * (c) Copyright 2003 Pádraig Brady <P@draigBrady.com> | ||
12 | * | ||
13 | * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl> | ||
14 | * | ||
15 | * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved. | ||
16 | * http://www.redhat.com | ||
17 | * | ||
18 | * This program is free software; you can redistribute it and/or | ||
19 | * modify it under the terms of the GNU General Public License | ||
20 | * as published by the Free Software Foundation; either version | ||
21 | * 2 of the License, or (at your option) any later version. | ||
22 | * | ||
23 | * Neither Marcus Junker nor ANDURAS AG admit liability nor provide | ||
24 | * warranty for any of this software. This material is provided | ||
25 | * "AS-IS" and at no charge. | ||
26 | */ | ||
27 | |||
28 | #include <linux/module.h> | ||
29 | #include <linux/moduleparam.h> | ||
30 | #include <linux/types.h> | ||
31 | #include <linux/miscdevice.h> | ||
32 | #include <linux/watchdog.h> | ||
33 | #include <linux/fs.h> | ||
34 | #include <linux/ioport.h> | ||
35 | #include <linux/notifier.h> | ||
36 | #include <linux/reboot.h> | ||
37 | #include <linux/init.h> | ||
38 | #include <linux/spinlock.h> | ||
39 | |||
40 | #include <asm/io.h> | ||
41 | #include <asm/uaccess.h> | ||
42 | #include <asm/system.h> | ||
43 | |||
44 | #define WATCHDOG_NAME "w83697hf/hg WDT" | ||
45 | #define PFX WATCHDOG_NAME ": " | ||
46 | #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ | ||
47 | |||
48 | static unsigned long wdt_is_open; | ||
49 | static char expect_close; | ||
50 | static spinlock_t io_lock; | ||
51 | |||
52 | /* You must set this - there is no sane way to probe for this board. */ | ||
53 | static int wdt_io = 0x2e; | ||
54 | module_param(wdt_io, int, 0); | ||
55 | MODULE_PARM_DESC(wdt_io, "w83697hf/hg WDT io port (default 0x2e, 0 = autodetect)"); | ||
56 | |||
57 | static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ | ||
58 | module_param(timeout, int, 0); | ||
59 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); | ||
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 | * Kernel methods. | ||
67 | */ | ||
68 | |||
69 | #define W83697HF_EFER (wdt_io+0) /* Extended Function Enable Register */ | ||
70 | #define W83697HF_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */ | ||
71 | #define W83697HF_EFDR (wdt_io+1) /* Extended Function Data Register */ | ||
72 | |||
73 | static inline void | ||
74 | w83697hf_unlock(void) | ||
75 | { | ||
76 | outb_p(0x87, W83697HF_EFER); /* Enter extended function mode */ | ||
77 | outb_p(0x87, W83697HF_EFER); /* Again according to manual */ | ||
78 | } | ||
79 | |||
80 | static inline void | ||
81 | w83697hf_lock(void) | ||
82 | { | ||
83 | outb_p(0xAA, W83697HF_EFER); /* Leave extended function mode */ | ||
84 | } | ||
85 | |||
86 | /* | ||
87 | * The three functions w83697hf_get_reg(), w83697hf_set_reg() and | ||
88 | * w83697hf_write_timeout() must be called with the device unlocked. | ||
89 | */ | ||
90 | |||
91 | static unsigned char | ||
92 | w83697hf_get_reg(unsigned char reg) | ||
93 | { | ||
94 | outb_p(reg, W83697HF_EFIR); | ||
95 | return inb_p(W83697HF_EFDR); | ||
96 | } | ||
97 | |||
98 | static void | ||
99 | w83697hf_set_reg(unsigned char reg, unsigned char data) | ||
100 | { | ||
101 | outb_p(reg, W83697HF_EFIR); | ||
102 | outb_p(data, W83697HF_EFDR); | ||
103 | } | ||
104 | |||
105 | static void | ||
106 | w83697hf_write_timeout(int timeout) | ||
107 | { | ||
108 | w83697hf_set_reg(0xF4, timeout); /* Write Timeout counter to CRF4 */ | ||
109 | } | ||
110 | |||
111 | static void | ||
112 | w83697hf_select_wdt(void) | ||
113 | { | ||
114 | w83697hf_unlock(); | ||
115 | w83697hf_set_reg(0x07, 0x08); /* Switch to logic device 8 (GPIO2) */ | ||
116 | } | ||
117 | |||
118 | static inline void | ||
119 | w83697hf_deselect_wdt(void) | ||
120 | { | ||
121 | w83697hf_lock(); | ||
122 | } | ||
123 | |||
124 | static void | ||
125 | w83697hf_init(void) | ||
126 | { | ||
127 | unsigned char bbuf; | ||
128 | |||
129 | w83697hf_select_wdt(); | ||
130 | |||
131 | bbuf = w83697hf_get_reg(0x29); | ||
132 | bbuf &= ~0x60; | ||
133 | bbuf |= 0x20; | ||
134 | w83697hf_set_reg(0x29, bbuf); /* Set pin 119 to WDTO# mode (= CR29, WDT0) */ | ||
135 | |||
136 | bbuf = w83697hf_get_reg(0xF3); | ||
137 | bbuf &= ~0x04; | ||
138 | w83697hf_set_reg(0xF3, bbuf); /* Count mode is seconds */ | ||
139 | |||
140 | w83697hf_deselect_wdt(); | ||
141 | } | ||
142 | |||
143 | static int | ||
144 | wdt_ping(void) | ||
145 | { | ||
146 | spin_lock(&io_lock); | ||
147 | w83697hf_select_wdt(); | ||
148 | |||
149 | w83697hf_write_timeout(timeout); | ||
150 | |||
151 | w83697hf_deselect_wdt(); | ||
152 | spin_unlock(&io_lock); | ||
153 | return 0; | ||
154 | } | ||
155 | |||
156 | static int | ||
157 | wdt_enable(void) | ||
158 | { | ||
159 | spin_lock(&io_lock); | ||
160 | w83697hf_select_wdt(); | ||
161 | |||
162 | w83697hf_write_timeout(timeout); | ||
163 | w83697hf_set_reg(0x30, 1); /* Enable timer */ | ||
164 | |||
165 | w83697hf_deselect_wdt(); | ||
166 | spin_unlock(&io_lock); | ||
167 | return 0; | ||
168 | } | ||
169 | |||
170 | static int | ||
171 | wdt_disable(void) | ||
172 | { | ||
173 | spin_lock(&io_lock); | ||
174 | w83697hf_select_wdt(); | ||
175 | |||
176 | w83697hf_set_reg(0x30, 0); /* Disable timer */ | ||
177 | w83697hf_write_timeout(0); | ||
178 | |||
179 | w83697hf_deselect_wdt(); | ||
180 | spin_unlock(&io_lock); | ||
181 | return 0; | ||
182 | } | ||
183 | |||
184 | static int | ||
185 | wdt_set_heartbeat(int t) | ||
186 | { | ||
187 | if ((t < 1) || (t > 255)) | ||
188 | return -EINVAL; | ||
189 | |||
190 | timeout = t; | ||
191 | return 0; | ||
192 | } | ||
193 | |||
194 | static ssize_t | ||
195 | wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) | ||
196 | { | ||
197 | if (count) { | ||
198 | if (!nowayout) { | ||
199 | size_t i; | ||
200 | |||
201 | expect_close = 0; | ||
202 | |||
203 | for (i = 0; i != count; i++) { | ||
204 | char c; | ||
205 | if (get_user(c, buf+i)) | ||
206 | return -EFAULT; | ||
207 | if (c == 'V') | ||
208 | expect_close = 42; | ||
209 | } | ||
210 | } | ||
211 | wdt_ping(); | ||
212 | } | ||
213 | return count; | ||
214 | } | ||
215 | |||
216 | static int | ||
217 | wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | ||
218 | unsigned long arg) | ||
219 | { | ||
220 | void __user *argp = (void __user *)arg; | ||
221 | int __user *p = argp; | ||
222 | int new_timeout; | ||
223 | static struct watchdog_info ident = { | ||
224 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, | ||
225 | .firmware_version = 1, | ||
226 | .identity = "W83697HF WDT", | ||
227 | }; | ||
228 | |||
229 | switch (cmd) { | ||
230 | case WDIOC_GETSUPPORT: | ||
231 | if (copy_to_user(argp, &ident, sizeof(ident))) | ||
232 | return -EFAULT; | ||
233 | break; | ||
234 | |||
235 | case WDIOC_GETSTATUS: | ||
236 | case WDIOC_GETBOOTSTATUS: | ||
237 | return put_user(0, p); | ||
238 | |||
239 | case WDIOC_KEEPALIVE: | ||
240 | wdt_ping(); | ||
241 | break; | ||
242 | |||
243 | case WDIOC_SETTIMEOUT: | ||
244 | if (get_user(new_timeout, p)) | ||
245 | return -EFAULT; | ||
246 | if (wdt_set_heartbeat(new_timeout)) | ||
247 | return -EINVAL; | ||
248 | wdt_ping(); | ||
249 | /* Fall */ | ||
250 | |||
251 | case WDIOC_GETTIMEOUT: | ||
252 | return put_user(timeout, p); | ||
253 | |||
254 | case WDIOC_SETOPTIONS: | ||
255 | { | ||
256 | int options, retval = -EINVAL; | ||
257 | |||
258 | if (get_user(options, p)) | ||
259 | return -EFAULT; | ||
260 | |||
261 | if (options & WDIOS_DISABLECARD) { | ||
262 | wdt_disable(); | ||
263 | retval = 0; | ||
264 | } | ||
265 | |||
266 | if (options & WDIOS_ENABLECARD) { | ||
267 | wdt_enable(); | ||
268 | retval = 0; | ||
269 | } | ||
270 | |||
271 | return retval; | ||
272 | } | ||
273 | |||
274 | default: | ||
275 | return -ENOTTY; | ||
276 | } | ||
277 | return 0; | ||
278 | } | ||
279 | |||
280 | static int | ||
281 | wdt_open(struct inode *inode, struct file *file) | ||
282 | { | ||
283 | if (test_and_set_bit(0, &wdt_is_open)) | ||
284 | return -EBUSY; | ||
285 | /* | ||
286 | * Activate | ||
287 | */ | ||
288 | |||
289 | wdt_enable(); | ||
290 | return nonseekable_open(inode, file); | ||
291 | } | ||
292 | |||
293 | static int | ||
294 | wdt_close(struct inode *inode, struct file *file) | ||
295 | { | ||
296 | if (expect_close == 42) { | ||
297 | wdt_disable(); | ||
298 | } else { | ||
299 | printk (KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n"); | ||
300 | wdt_ping(); | ||
301 | } | ||
302 | expect_close = 0; | ||
303 | clear_bit(0, &wdt_is_open); | ||
304 | return 0; | ||
305 | } | ||
306 | |||
307 | /* | ||
308 | * Notifier for system down | ||
309 | */ | ||
310 | |||
311 | static int | ||
312 | wdt_notify_sys(struct notifier_block *this, unsigned long code, | ||
313 | void *unused) | ||
314 | { | ||
315 | if (code == SYS_DOWN || code == SYS_HALT) { | ||
316 | /* Turn the WDT off */ | ||
317 | wdt_disable(); | ||
318 | } | ||
319 | return NOTIFY_DONE; | ||
320 | } | ||
321 | |||
322 | /* | ||
323 | * Kernel Interfaces | ||
324 | */ | ||
325 | |||
326 | static struct file_operations wdt_fops = { | ||
327 | .owner = THIS_MODULE, | ||
328 | .llseek = no_llseek, | ||
329 | .write = wdt_write, | ||
330 | .ioctl = wdt_ioctl, | ||
331 | .open = wdt_open, | ||
332 | .release = wdt_close, | ||
333 | }; | ||
334 | |||
335 | static struct miscdevice wdt_miscdev = { | ||
336 | .minor = WATCHDOG_MINOR, | ||
337 | .name = "watchdog", | ||
338 | .fops = &wdt_fops, | ||
339 | }; | ||
340 | |||
341 | /* | ||
342 | * The WDT needs to learn about soft shutdowns in order to | ||
343 | * turn the timebomb registers off. | ||
344 | */ | ||
345 | |||
346 | static struct notifier_block wdt_notifier = { | ||
347 | .notifier_call = wdt_notify_sys, | ||
348 | }; | ||
349 | |||
350 | static int | ||
351 | w83697hf_check_wdt(void) | ||
352 | { | ||
353 | if (!request_region(wdt_io, 2, WATCHDOG_NAME)) { | ||
354 | printk (KERN_ERR PFX "I/O address 0x%x already in use\n", wdt_io); | ||
355 | return -EIO; | ||
356 | } | ||
357 | |||
358 | printk (KERN_DEBUG PFX "Looking for watchdog at address 0x%x\n", wdt_io); | ||
359 | w83697hf_unlock(); | ||
360 | if (w83697hf_get_reg(0x20) == 0x60) { | ||
361 | printk (KERN_INFO PFX "watchdog found at address 0x%x\n", wdt_io); | ||
362 | w83697hf_lock(); | ||
363 | return 0; | ||
364 | } | ||
365 | w83697hf_lock(); /* Reprotect in case it was a compatible device */ | ||
366 | |||
367 | printk (KERN_INFO PFX "watchdog not found at address 0x%x\n", wdt_io); | ||
368 | release_region(wdt_io, 2); | ||
369 | return -EIO; | ||
370 | } | ||
371 | |||
372 | static int w83697hf_ioports[] = { 0x2e, 0x4e, 0x00 }; | ||
373 | |||
374 | static int __init | ||
375 | wdt_init(void) | ||
376 | { | ||
377 | int ret, i, found = 0; | ||
378 | |||
379 | spin_lock_init(&io_lock); | ||
380 | |||
381 | printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n"); | ||
382 | |||
383 | if (wdt_io == 0) { | ||
384 | /* we will autodetect the W83697HF/HG watchdog */ | ||
385 | for (i = 0; ((!found) && (w83697hf_ioports[i] != 0)); i++) { | ||
386 | wdt_io = w83697hf_ioports[i]; | ||
387 | if (!w83697hf_check_wdt()) | ||
388 | found++; | ||
389 | } | ||
390 | } else { | ||
391 | if (!w83697hf_check_wdt()) | ||
392 | found++; | ||
393 | } | ||
394 | |||
395 | if (!found) { | ||
396 | printk (KERN_ERR PFX "No W83697HF/HG could be found\n"); | ||
397 | ret = -EIO; | ||
398 | goto out; | ||
399 | } | ||
400 | |||
401 | w83697hf_init(); | ||
402 | wdt_disable(); /* Disable watchdog until first use */ | ||
403 | |||
404 | if (wdt_set_heartbeat(timeout)) { | ||
405 | wdt_set_heartbeat(WATCHDOG_TIMEOUT); | ||
406 | printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n", | ||
407 | WATCHDOG_TIMEOUT); | ||
408 | } | ||
409 | |||
410 | ret = register_reboot_notifier(&wdt_notifier); | ||
411 | if (ret != 0) { | ||
412 | printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", | ||
413 | ret); | ||
414 | goto unreg_regions; | ||
415 | } | ||
416 | |||
417 | ret = misc_register(&wdt_miscdev); | ||
418 | if (ret != 0) { | ||
419 | printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | ||
420 | WATCHDOG_MINOR, ret); | ||
421 | goto unreg_reboot; | ||
422 | } | ||
423 | |||
424 | printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n", | ||
425 | timeout, nowayout); | ||
426 | |||
427 | out: | ||
428 | return ret; | ||
429 | unreg_reboot: | ||
430 | unregister_reboot_notifier(&wdt_notifier); | ||
431 | unreg_regions: | ||
432 | release_region(wdt_io, 2); | ||
433 | goto out; | ||
434 | } | ||
435 | |||
436 | static void __exit | ||
437 | wdt_exit(void) | ||
438 | { | ||
439 | misc_deregister(&wdt_miscdev); | ||
440 | unregister_reboot_notifier(&wdt_notifier); | ||
441 | release_region(wdt_io, 2); | ||
442 | } | ||
443 | |||
444 | module_init(wdt_init); | ||
445 | module_exit(wdt_exit); | ||
446 | |||
447 | MODULE_LICENSE("GPL"); | ||
448 | MODULE_AUTHOR("Marcus Junker <junker@anduras.de>, Samuel Tardieu <sam@rfc1149.net>"); | ||
449 | MODULE_DESCRIPTION("w83697hf/hg WDT driver"); | ||
450 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||