Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 | 2 | /* |
4dab06fa | 3 | * Wdt977 0.04: A Watchdog Device for Netwinder W83977AF chip |
1da177e4 LT |
4 | * |
5 | * (c) Copyright 1998 Rebel.com (Woody Suwalski <woody@netwinder.org>) | |
6 | * | |
7 | * ----------------------- | |
8 | * | |
1da177e4 LT |
9 | * ----------------------- |
10 | * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com> | |
11 | * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT | |
12 | * 19-Dec-2001 Woody Suwalski: Netwinder fixes, ioctl interface | |
13 | * 06-Jan-2002 Woody Suwalski: For compatibility, convert all timeouts | |
14 | * from minutes to seconds. | |
15 | * 07-Jul-2003 Daniele Bellucci: Audit return code of misc_register in | |
16 | * nwwatchdog_init. | |
4dab06fa | 17 | * 25-Oct-2005 Woody Suwalski: Convert addresses to #defs, add spinlocks |
f2b79c6e AC |
18 | * remove limitiation to be used on |
19 | * Netwinders only | |
1da177e4 LT |
20 | */ |
21 | ||
27c766aa JP |
22 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
23 | ||
1da177e4 LT |
24 | #include <linux/module.h> |
25 | #include <linux/moduleparam.h> | |
1da177e4 LT |
26 | #include <linux/types.h> |
27 | #include <linux/kernel.h> | |
28 | #include <linux/fs.h> | |
29 | #include <linux/miscdevice.h> | |
30 | #include <linux/init.h> | |
4dab06fa | 31 | #include <linux/ioport.h> |
1da177e4 LT |
32 | #include <linux/watchdog.h> |
33 | #include <linux/notifier.h> | |
34 | #include <linux/reboot.h> | |
f2b79c6e AC |
35 | #include <linux/io.h> |
36 | #include <linux/uaccess.h> | |
1da177e4 | 37 | |
1da177e4 | 38 | #include <asm/mach-types.h> |
1da177e4 | 39 | |
4dab06fa WS |
40 | #define WATCHDOG_VERSION "0.04" |
41 | #define WATCHDOG_NAME "Wdt977" | |
4dab06fa WS |
42 | |
43 | #define IO_INDEX_PORT 0x370 /* on some systems it can be 0x3F0 */ | |
f2b79c6e | 44 | #define IO_DATA_PORT (IO_INDEX_PORT + 1) |
4dab06fa WS |
45 | |
46 | #define UNLOCK_DATA 0x87 | |
47 | #define LOCK_DATA 0xAA | |
48 | #define DEVICE_REGISTER 0x07 | |
49 | ||
1da177e4 LT |
50 | |
51 | #define DEFAULT_TIMEOUT 60 /* default timeout in seconds */ | |
52 | ||
53 | static int timeout = DEFAULT_TIMEOUT; | |
54 | static int timeoutM; /* timeout in minutes */ | |
55 | static unsigned long timer_alive; | |
56 | static int testmode; | |
57 | static char expect_close; | |
c7dfd0cc | 58 | static DEFINE_SPINLOCK(spinlock); |
1da177e4 LT |
59 | |
60 | module_param(timeout, int, 0); | |
76550d32 | 61 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (60..15300, default=" |
f2b79c6e | 62 | __MODULE_STRING(DEFAULT_TIMEOUT) ")"); |
1da177e4 | 63 | module_param(testmode, int, 0); |
f2b79c6e | 64 | MODULE_PARM_DESC(testmode, "Watchdog testmode (1 = no reboot), default=0"); |
1da177e4 | 65 | |
86a1e189 WVS |
66 | static bool nowayout = WATCHDOG_NOWAYOUT; |
67 | module_param(nowayout, bool, 0); | |
f2b79c6e AC |
68 | MODULE_PARM_DESC(nowayout, |
69 | "Watchdog cannot be stopped once started (default=" | |
70 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | |
1da177e4 LT |
71 | |
72 | /* | |
73 | * Start the watchdog | |
74 | */ | |
75 | ||
76 | static int wdt977_start(void) | |
77 | { | |
4dab06fa WS |
78 | unsigned long flags; |
79 | ||
80 | spin_lock_irqsave(&spinlock, flags); | |
81 | ||
1da177e4 | 82 | /* unlock the SuperIO chip */ |
4dab06fa WS |
83 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); |
84 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); | |
1da177e4 LT |
85 | |
86 | /* select device Aux2 (device=8) and set watchdog regs F2, F3 and F4 | |
87 | * F2 has the timeout in minutes | |
88 | * F3 could be set to the POWER LED blink (with GP17 set to PowerLed) | |
89 | * at timeout, and to reset timer on kbd/mouse activity (not impl.) | |
90 | * F4 is used to just clear the TIMEOUT'ed state (bit 0) | |
91 | */ | |
4dab06fa WS |
92 | outb_p(DEVICE_REGISTER, IO_INDEX_PORT); |
93 | outb_p(0x08, IO_DATA_PORT); | |
94 | outb_p(0xF2, IO_INDEX_PORT); | |
95 | outb_p(timeoutM, IO_DATA_PORT); | |
96 | outb_p(0xF3, IO_INDEX_PORT); | |
f2b79c6e AC |
97 | outb_p(0x00, IO_DATA_PORT); /* another setting is 0E for |
98 | kbd/mouse/LED */ | |
4dab06fa WS |
99 | outb_p(0xF4, IO_INDEX_PORT); |
100 | outb_p(0x00, IO_DATA_PORT); | |
1da177e4 | 101 | |
f2b79c6e AC |
102 | /* At last select device Aux1 (dev=7) and set GP16 as a |
103 | * watchdog output. In test mode watch the bit 1 on F4 to | |
104 | * indicate "triggered" | |
105 | */ | |
106 | if (!testmode) { | |
4dab06fa WS |
107 | outb_p(DEVICE_REGISTER, IO_INDEX_PORT); |
108 | outb_p(0x07, IO_DATA_PORT); | |
109 | outb_p(0xE6, IO_INDEX_PORT); | |
110 | outb_p(0x08, IO_DATA_PORT); | |
1da177e4 LT |
111 | } |
112 | ||
113 | /* lock the SuperIO chip */ | |
4dab06fa | 114 | outb_p(LOCK_DATA, IO_INDEX_PORT); |
1da177e4 | 115 | |
4dab06fa | 116 | spin_unlock_irqrestore(&spinlock, flags); |
27c766aa | 117 | pr_info("activated\n"); |
1da177e4 LT |
118 | |
119 | return 0; | |
120 | } | |
121 | ||
122 | /* | |
123 | * Stop the watchdog | |
124 | */ | |
125 | ||
126 | static int wdt977_stop(void) | |
127 | { | |
4dab06fa WS |
128 | unsigned long flags; |
129 | spin_lock_irqsave(&spinlock, flags); | |
130 | ||
1da177e4 | 131 | /* unlock the SuperIO chip */ |
4dab06fa WS |
132 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); |
133 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); | |
1da177e4 LT |
134 | |
135 | /* select device Aux2 (device=8) and set watchdog regs F2,F3 and F4 | |
136 | * F3 is reset to its default state | |
137 | * F4 can clear the TIMEOUT'ed state (bit 0) - back to default | |
138 | * We can not use GP17 as a PowerLed, as we use its usage as a RedLed | |
139 | */ | |
4dab06fa WS |
140 | outb_p(DEVICE_REGISTER, IO_INDEX_PORT); |
141 | outb_p(0x08, IO_DATA_PORT); | |
142 | outb_p(0xF2, IO_INDEX_PORT); | |
143 | outb_p(0xFF, IO_DATA_PORT); | |
144 | outb_p(0xF3, IO_INDEX_PORT); | |
145 | outb_p(0x00, IO_DATA_PORT); | |
146 | outb_p(0xF4, IO_INDEX_PORT); | |
147 | outb_p(0x00, IO_DATA_PORT); | |
148 | outb_p(0xF2, IO_INDEX_PORT); | |
149 | outb_p(0x00, IO_DATA_PORT); | |
1da177e4 | 150 | |
f2b79c6e AC |
151 | /* at last select device Aux1 (dev=7) and set |
152 | GP16 as a watchdog output */ | |
4dab06fa WS |
153 | outb_p(DEVICE_REGISTER, IO_INDEX_PORT); |
154 | outb_p(0x07, IO_DATA_PORT); | |
155 | outb_p(0xE6, IO_INDEX_PORT); | |
156 | outb_p(0x08, IO_DATA_PORT); | |
1da177e4 LT |
157 | |
158 | /* lock the SuperIO chip */ | |
4dab06fa | 159 | outb_p(LOCK_DATA, IO_INDEX_PORT); |
1da177e4 | 160 | |
4dab06fa | 161 | spin_unlock_irqrestore(&spinlock, flags); |
27c766aa | 162 | pr_info("shutdown\n"); |
1da177e4 LT |
163 | |
164 | return 0; | |
165 | } | |
166 | ||
167 | /* | |
168 | * Send a keepalive ping to the watchdog | |
169 | * This is done by simply re-writing the timeout to reg. 0xF2 | |
170 | */ | |
171 | ||
172 | static int wdt977_keepalive(void) | |
173 | { | |
4dab06fa WS |
174 | unsigned long flags; |
175 | spin_lock_irqsave(&spinlock, flags); | |
176 | ||
1da177e4 | 177 | /* unlock the SuperIO chip */ |
4dab06fa WS |
178 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); |
179 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); | |
1da177e4 LT |
180 | |
181 | /* select device Aux2 (device=8) and kicks watchdog reg F2 */ | |
182 | /* F2 has the timeout in minutes */ | |
4dab06fa WS |
183 | outb_p(DEVICE_REGISTER, IO_INDEX_PORT); |
184 | outb_p(0x08, IO_DATA_PORT); | |
185 | outb_p(0xF2, IO_INDEX_PORT); | |
186 | outb_p(timeoutM, IO_DATA_PORT); | |
1da177e4 LT |
187 | |
188 | /* lock the SuperIO chip */ | |
4dab06fa WS |
189 | outb_p(LOCK_DATA, IO_INDEX_PORT); |
190 | spin_unlock_irqrestore(&spinlock, flags); | |
1da177e4 LT |
191 | |
192 | return 0; | |
193 | } | |
194 | ||
195 | /* | |
196 | * Set the watchdog timeout value | |
197 | */ | |
198 | ||
199 | static int wdt977_set_timeout(int t) | |
200 | { | |
201 | int tmrval; | |
202 | ||
203 | /* convert seconds to minutes, rounding up */ | |
204 | tmrval = (t + 59) / 60; | |
205 | ||
206 | if (machine_is_netwinder()) { | |
f2b79c6e AC |
207 | /* we have a hw bug somewhere, so each 977 minute is actually |
208 | * only 30sec. This limits the max timeout to half of device | |
209 | * max of 255 minutes... | |
1da177e4 LT |
210 | */ |
211 | tmrval += tmrval; | |
212 | } | |
213 | ||
f2b79c6e | 214 | if (tmrval < 1 || tmrval > 255) |
1da177e4 LT |
215 | return -EINVAL; |
216 | ||
f2b79c6e AC |
217 | /* timeout is the timeout in seconds, timeoutM is |
218 | the timeout in minutes) */ | |
1da177e4 LT |
219 | timeout = t; |
220 | timeoutM = tmrval; | |
221 | return 0; | |
222 | } | |
223 | ||
224 | /* | |
225 | * Get the watchdog status | |
226 | */ | |
227 | ||
228 | static int wdt977_get_status(int *status) | |
229 | { | |
230 | int new_status; | |
4dab06fa | 231 | unsigned long flags; |
1da177e4 | 232 | |
4dab06fa | 233 | spin_lock_irqsave(&spinlock, flags); |
1da177e4 LT |
234 | |
235 | /* unlock the SuperIO chip */ | |
4dab06fa WS |
236 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); |
237 | outb_p(UNLOCK_DATA, IO_INDEX_PORT); | |
1da177e4 LT |
238 | |
239 | /* select device Aux2 (device=8) and read watchdog reg F4 */ | |
4dab06fa WS |
240 | outb_p(DEVICE_REGISTER, IO_INDEX_PORT); |
241 | outb_p(0x08, IO_DATA_PORT); | |
242 | outb_p(0xF4, IO_INDEX_PORT); | |
243 | new_status = inb_p(IO_DATA_PORT); | |
1da177e4 LT |
244 | |
245 | /* lock the SuperIO chip */ | |
4dab06fa | 246 | outb_p(LOCK_DATA, IO_INDEX_PORT); |
1da177e4 | 247 | |
4dab06fa WS |
248 | spin_unlock_irqrestore(&spinlock, flags); |
249 | ||
f2b79c6e | 250 | *status = 0; |
1da177e4 LT |
251 | if (new_status & 1) |
252 | *status |= WDIOF_CARDRESET; | |
253 | ||
254 | return 0; | |
255 | } | |
256 | ||
257 | ||
258 | /* | |
259 | * /dev/watchdog handling | |
260 | */ | |
261 | ||
262 | static int wdt977_open(struct inode *inode, struct file *file) | |
263 | { | |
264 | /* If the watchdog is alive we don't need to start it again */ | |
f2b79c6e | 265 | if (test_and_set_bit(0, &timer_alive)) |
1da177e4 LT |
266 | return -EBUSY; |
267 | ||
268 | if (nowayout) | |
269 | __module_get(THIS_MODULE); | |
270 | ||
271 | wdt977_start(); | |
c5bf68fe | 272 | return stream_open(inode, file); |
1da177e4 LT |
273 | } |
274 | ||
275 | static int wdt977_release(struct inode *inode, struct file *file) | |
276 | { | |
277 | /* | |
278 | * Shut off the timer. | |
5f3b2756 | 279 | * Lock it in if it's a module and we set nowayout |
1da177e4 | 280 | */ |
f2b79c6e | 281 | if (expect_close == 42) { |
1da177e4 | 282 | wdt977_stop(); |
f2b79c6e | 283 | clear_bit(0, &timer_alive); |
1da177e4 | 284 | } else { |
1da177e4 | 285 | wdt977_keepalive(); |
27c766aa | 286 | pr_crit("Unexpected close, not stopping watchdog!\n"); |
1da177e4 LT |
287 | } |
288 | expect_close = 0; | |
289 | return 0; | |
290 | } | |
291 | ||
292 | ||
293 | /* | |
294 | * wdt977_write: | |
295 | * @file: file handle to the watchdog | |
296 | * @buf: buffer to write (unused as data does not matter here | |
297 | * @count: count of bytes | |
298 | * @ppos: pointer to the position to write. No seeks allowed | |
299 | * | |
300 | * A write to a watchdog device is defined as a keepalive signal. Any | |
301 | * write of data will do, as we we don't define content meaning. | |
302 | */ | |
303 | ||
304 | static ssize_t wdt977_write(struct file *file, const char __user *buf, | |
305 | size_t count, loff_t *ppos) | |
306 | { | |
f2b79c6e AC |
307 | if (count) { |
308 | if (!nowayout) { | |
1da177e4 LT |
309 | size_t i; |
310 | ||
311 | /* In case it was set long ago */ | |
312 | expect_close = 0; | |
313 | ||
f2b79c6e | 314 | for (i = 0; i != count; i++) { |
1da177e4 LT |
315 | char c; |
316 | if (get_user(c, buf + i)) | |
317 | return -EFAULT; | |
318 | if (c == 'V') | |
319 | expect_close = 42; | |
320 | } | |
321 | } | |
322 | ||
4dab06fa | 323 | /* someone wrote to us, we should restart timer */ |
1da177e4 LT |
324 | wdt977_keepalive(); |
325 | } | |
326 | return count; | |
327 | } | |
328 | ||
f2b79c6e AC |
329 | static const struct watchdog_info ident = { |
330 | .options = WDIOF_SETTIMEOUT | | |
331 | WDIOF_MAGICCLOSE | | |
332 | WDIOF_KEEPALIVEPING, | |
333 | .firmware_version = 1, | |
334 | .identity = WATCHDOG_NAME, | |
335 | }; | |
336 | ||
1da177e4 LT |
337 | /* |
338 | * wdt977_ioctl: | |
339 | * @inode: inode of the device | |
340 | * @file: file handle to the device | |
341 | * @cmd: watchdog command | |
342 | * @arg: argument pointer | |
343 | * | |
344 | * The watchdog API defines a common set of functions for all watchdogs | |
345 | * according to their available features. | |
346 | */ | |
347 | ||
f2b79c6e AC |
348 | static long wdt977_ioctl(struct file *file, unsigned int cmd, |
349 | unsigned long arg) | |
1da177e4 LT |
350 | { |
351 | int status; | |
352 | int new_options, retval = -EINVAL; | |
353 | int new_timeout; | |
354 | union { | |
355 | struct watchdog_info __user *ident; | |
356 | int __user *i; | |
357 | } uarg; | |
358 | ||
359 | uarg.i = (int __user *)arg; | |
360 | ||
f2b79c6e | 361 | switch (cmd) { |
1da177e4 LT |
362 | case WDIOC_GETSUPPORT: |
363 | return copy_to_user(uarg.ident, &ident, | |
364 | sizeof(ident)) ? -EFAULT : 0; | |
365 | ||
366 | case WDIOC_GETSTATUS: | |
367 | wdt977_get_status(&status); | |
368 | return put_user(status, uarg.i); | |
369 | ||
370 | case WDIOC_GETBOOTSTATUS: | |
371 | return put_user(0, uarg.i); | |
372 | ||
1da177e4 | 373 | case WDIOC_SETOPTIONS: |
f2b79c6e | 374 | if (get_user(new_options, uarg.i)) |
1da177e4 LT |
375 | return -EFAULT; |
376 | ||
377 | if (new_options & WDIOS_DISABLECARD) { | |
378 | wdt977_stop(); | |
379 | retval = 0; | |
380 | } | |
381 | ||
382 | if (new_options & WDIOS_ENABLECARD) { | |
383 | wdt977_start(); | |
384 | retval = 0; | |
385 | } | |
386 | ||
387 | return retval; | |
388 | ||
0c06090c WVS |
389 | case WDIOC_KEEPALIVE: |
390 | wdt977_keepalive(); | |
391 | return 0; | |
392 | ||
1da177e4 LT |
393 | case WDIOC_SETTIMEOUT: |
394 | if (get_user(new_timeout, uarg.i)) | |
395 | return -EFAULT; | |
396 | ||
397 | if (wdt977_set_timeout(new_timeout)) | |
143a2e54 | 398 | return -EINVAL; |
1da177e4 LT |
399 | |
400 | wdt977_keepalive(); | |
401 | /* Fall */ | |
402 | ||
403 | case WDIOC_GETTIMEOUT: | |
404 | return put_user(timeout, uarg.i); | |
405 | ||
0c06090c WVS |
406 | default: |
407 | return -ENOTTY; | |
408 | ||
1da177e4 LT |
409 | } |
410 | } | |
411 | ||
412 | static int wdt977_notify_sys(struct notifier_block *this, unsigned long code, | |
413 | void *unused) | |
414 | { | |
f2b79c6e | 415 | if (code == SYS_DOWN || code == SYS_HALT) |
1da177e4 LT |
416 | wdt977_stop(); |
417 | return NOTIFY_DONE; | |
418 | } | |
419 | ||
f2b79c6e | 420 | static const struct file_operations wdt977_fops = { |
1da177e4 LT |
421 | .owner = THIS_MODULE, |
422 | .llseek = no_llseek, | |
423 | .write = wdt977_write, | |
f2b79c6e | 424 | .unlocked_ioctl = wdt977_ioctl, |
1da177e4 LT |
425 | .open = wdt977_open, |
426 | .release = wdt977_release, | |
427 | }; | |
428 | ||
f2b79c6e | 429 | static struct miscdevice wdt977_miscdev = { |
1da177e4 LT |
430 | .minor = WATCHDOG_MINOR, |
431 | .name = "watchdog", | |
432 | .fops = &wdt977_fops, | |
433 | }; | |
434 | ||
435 | static struct notifier_block wdt977_notifier = { | |
436 | .notifier_call = wdt977_notify_sys, | |
437 | }; | |
438 | ||
4dab06fa | 439 | static int __init wd977_init(void) |
1da177e4 | 440 | { |
4dab06fa WS |
441 | int rc; |
442 | ||
27c766aa | 443 | pr_info("driver v%s\n", WATCHDOG_VERSION); |
4dab06fa | 444 | |
f2b79c6e AC |
445 | /* Check that the timeout value is within its range; |
446 | if not reset to the default */ | |
447 | if (wdt977_set_timeout(timeout)) { | |
1da177e4 | 448 | wdt977_set_timeout(DEFAULT_TIMEOUT); |
27c766aa JP |
449 | pr_info("timeout value must be 60 < timeout < 15300, using %d\n", |
450 | DEFAULT_TIMEOUT); | |
1da177e4 LT |
451 | } |
452 | ||
4dab06fa WS |
453 | /* on Netwinder the IOports are already reserved by |
454 | * arch/arm/mach-footbridge/netwinder-hw.c | |
455 | */ | |
f2b79c6e AC |
456 | if (!machine_is_netwinder()) { |
457 | if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME)) { | |
27c766aa JP |
458 | pr_err("I/O address 0x%04x already in use\n", |
459 | IO_INDEX_PORT); | |
4dab06fa WS |
460 | rc = -EIO; |
461 | goto err_out; | |
462 | } | |
1da177e4 LT |
463 | } |
464 | ||
c6cb13ae | 465 | rc = register_reboot_notifier(&wdt977_notifier); |
f2b79c6e | 466 | if (rc) { |
27c766aa | 467 | pr_err("cannot register reboot notifier (err=%d)\n", rc); |
4dab06fa WS |
468 | goto err_out_region; |
469 | } | |
470 | ||
c6cb13ae | 471 | rc = misc_register(&wdt977_miscdev); |
f2b79c6e | 472 | if (rc) { |
27c766aa JP |
473 | pr_err("cannot register miscdev on minor=%d (err=%d)\n", |
474 | wdt977_miscdev.minor, rc); | |
c6cb13ae | 475 | goto err_out_reboot; |
1da177e4 LT |
476 | } |
477 | ||
27c766aa JP |
478 | pr_info("initialized. timeout=%d sec (nowayout=%d, testmode=%i)\n", |
479 | timeout, nowayout, testmode); | |
1da177e4 LT |
480 | |
481 | return 0; | |
4dab06fa | 482 | |
c6cb13ae WVS |
483 | err_out_reboot: |
484 | unregister_reboot_notifier(&wdt977_notifier); | |
4dab06fa WS |
485 | err_out_region: |
486 | if (!machine_is_netwinder()) | |
f2b79c6e | 487 | release_region(IO_INDEX_PORT, 2); |
4dab06fa WS |
488 | err_out: |
489 | return rc; | |
1da177e4 LT |
490 | } |
491 | ||
4dab06fa | 492 | static void __exit wd977_exit(void) |
1da177e4 | 493 | { |
4dab06fa | 494 | wdt977_stop(); |
1da177e4 LT |
495 | misc_deregister(&wdt977_miscdev); |
496 | unregister_reboot_notifier(&wdt977_notifier); | |
f2b79c6e | 497 | release_region(IO_INDEX_PORT, 2); |
1da177e4 LT |
498 | } |
499 | ||
4dab06fa WS |
500 | module_init(wd977_init); |
501 | module_exit(wd977_exit); | |
1da177e4 | 502 | |
4dab06fa | 503 | MODULE_AUTHOR("Woody Suwalski <woodys@xandros.com>"); |
1da177e4 LT |
504 | MODULE_DESCRIPTION("W83977AF Watchdog driver"); |
505 | MODULE_LICENSE("GPL"); |