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Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
Alan Cox04bedfa2009-03-22 10:46:42 +00002 * Industrial Computer Source WDT501 driver
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 *
Alan Cox29fa0582008-10-27 15:17:56 +00004 * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>,
5 * All Rights Reserved.
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
13 * warranty for any of this software. This material is provided
14 * "AS-IS" and at no charge.
15 *
16 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
17 *
18 * Release 0.10.
19 *
20 * Fixes
21 * Dave Gregorich : Modularisation and minor bugs
22 * Alan Cox : Added the watchdog ioctl() stuff
23 * Alan Cox : Fixed the reboot problem (as noted by
24 * Matt Crocker).
25 * Alan Cox : Added wdt= boot option
26 * Alan Cox : Cleaned up copy/user stuff
Alan Cox9f2d1f02008-08-04 17:55:35 +010027 * Tim Hockin : Added insmod parameters, comment
28 * cleanup, parameterized timeout
29 * Tigran Aivazian : Restructured wdt_init() to handle
30 * failures
Linus Torvalds1da177e2005-04-16 15:20:36 -070031 * Joel Becker : Added WDIOC_GET/SETTIMEOUT
32 * Matt Domsch : Added nowayout module option
33 */
34
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include <linux/interrupt.h>
36#include <linux/module.h>
37#include <linux/moduleparam.h>
38#include <linux/types.h>
39#include <linux/miscdevice.h>
40#include <linux/watchdog.h>
41#include <linux/fs.h>
42#include <linux/ioport.h>
43#include <linux/notifier.h>
44#include <linux/reboot.h>
45#include <linux/init.h>
Alan Cox9f2d1f02008-08-04 17:55:35 +010046#include <linux/io.h>
47#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070048
Linus Torvalds1da177e2005-04-16 15:20:36 -070049#include <asm/system.h>
50#include "wd501p.h"
51
52static unsigned long wdt_is_open;
53static char expect_close;
54
55/*
56 * Module parameters
57 */
58
59#define WD_TIMO 60 /* Default heartbeat = 60 seconds */
60
61static int heartbeat = WD_TIMO;
62static int wd_heartbeat;
63module_param(heartbeat, int, 0);
Alan Cox9f2d1f02008-08-04 17:55:35 +010064MODULE_PARM_DESC(heartbeat,
65 "Watchdog heartbeat in seconds. (0 < heartbeat < 65536, default="
66 __MODULE_STRING(WD_TIMO) ")");
Linus Torvalds1da177e2005-04-16 15:20:36 -070067
Andrey Panin4bfdf372005-07-27 11:43:58 -070068static int nowayout = WATCHDOG_NOWAYOUT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070069module_param(nowayout, int, 0);
Alan Cox9f2d1f02008-08-04 17:55:35 +010070MODULE_PARM_DESC(nowayout,
71 "Watchdog cannot be stopped once started (default="
72 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
Linus Torvalds1da177e2005-04-16 15:20:36 -070073
74/* You must set these - there is no sane way to probe for this board. */
Alan Cox9f2d1f02008-08-04 17:55:35 +010075static int io = 0x240;
76static int irq = 11;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
Alan Cox01c785d2008-01-09 21:36:01 -080078static DEFINE_SPINLOCK(wdt_lock);
79
Linus Torvalds1da177e2005-04-16 15:20:36 -070080module_param(io, int, 0);
81MODULE_PARM_DESC(io, "WDT io port (default=0x240)");
82module_param(irq, int, 0);
83MODULE_PARM_DESC(irq, "WDT irq (default=11)");
84
Linus Torvalds1da177e2005-04-16 15:20:36 -070085/* Support for the Fan Tachometer on the WDT501-P */
86static int tachometer;
Linus Torvalds1da177e2005-04-16 15:20:36 -070087module_param(tachometer, int, 0);
Alan Cox9f2d1f02008-08-04 17:55:35 +010088MODULE_PARM_DESC(tachometer,
89 "WDT501-P Fan Tachometer support (0=disable, default=0)");
Alan Cox04bedfa2009-03-22 10:46:42 +000090
91static int type = 500;
92module_param(type, int, 0);
93MODULE_PARM_DESC(type,
Randy Dunlap4724ba52010-05-03 11:42:52 -070094 "WDT501-P Card type (500 or 501, default=500)");
Linus Torvalds1da177e2005-04-16 15:20:36 -070095
96/*
97 * Programming support
98 */
99
100static void wdt_ctr_mode(int ctr, int mode)
101{
Alan Cox9f2d1f02008-08-04 17:55:35 +0100102 ctr <<= 6;
103 ctr |= 0x30;
104 ctr |= (mode << 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 outb_p(ctr, WDT_CR);
106}
107
108static void wdt_ctr_load(int ctr, int val)
109{
110 outb_p(val&0xFF, WDT_COUNT0+ctr);
111 outb_p(val>>8, WDT_COUNT0+ctr);
112}
113
114/**
115 * wdt_start:
116 *
117 * Start the watchdog driver.
118 */
119
120static int wdt_start(void)
121{
Alan Cox01c785d2008-01-09 21:36:01 -0800122 unsigned long flags;
123 spin_lock_irqsave(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700124 inb_p(WDT_DC); /* Disable watchdog */
Alan Cox9f2d1f02008-08-04 17:55:35 +0100125 wdt_ctr_mode(0, 3); /* Program CTR0 for Mode 3:
126 Square Wave Generator */
127 wdt_ctr_mode(1, 2); /* Program CTR1 for Mode 2:
128 Rate Generator */
129 wdt_ctr_mode(2, 0); /* Program CTR2 for Mode 0:
130 Pulse on Terminal Count */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700131 wdt_ctr_load(0, 8948); /* Count at 100Hz */
Alan Cox9f2d1f02008-08-04 17:55:35 +0100132 wdt_ctr_load(1, wd_heartbeat); /* Heartbeat */
133 wdt_ctr_load(2, 65535); /* Length of reset pulse */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 outb_p(0, WDT_DC); /* Enable watchdog */
Alan Cox01c785d2008-01-09 21:36:01 -0800135 spin_unlock_irqrestore(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 return 0;
137}
138
139/**
140 * wdt_stop:
141 *
142 * Stop the watchdog driver.
143 */
144
Alan Cox9f2d1f02008-08-04 17:55:35 +0100145static int wdt_stop(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700146{
Alan Cox01c785d2008-01-09 21:36:01 -0800147 unsigned long flags;
148 spin_lock_irqsave(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 /* Turn the card off */
150 inb_p(WDT_DC); /* Disable watchdog */
Alan Cox9f2d1f02008-08-04 17:55:35 +0100151 wdt_ctr_load(2, 0); /* 0 length reset pulses now */
Alan Cox01c785d2008-01-09 21:36:01 -0800152 spin_unlock_irqrestore(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700153 return 0;
154}
155
156/**
157 * wdt_ping:
158 *
Alan Cox9f2d1f02008-08-04 17:55:35 +0100159 * Reload counter one with the watchdog heartbeat. We don't bother
160 * reloading the cascade counter.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 */
162
Alan Cox04bedfa2009-03-22 10:46:42 +0000163static void wdt_ping(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700164{
Alan Cox01c785d2008-01-09 21:36:01 -0800165 unsigned long flags;
166 spin_lock_irqsave(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 /* Write a watchdog value */
168 inb_p(WDT_DC); /* Disable watchdog */
Alan Cox9f2d1f02008-08-04 17:55:35 +0100169 wdt_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2:
170 Rate Generator */
171 wdt_ctr_load(1, wd_heartbeat); /* Heartbeat */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172 outb_p(0, WDT_DC); /* Enable watchdog */
Alan Cox01c785d2008-01-09 21:36:01 -0800173 spin_unlock_irqrestore(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174}
175
176/**
177 * wdt_set_heartbeat:
178 * @t: the new heartbeat value that needs to be set.
179 *
Alan Cox9f2d1f02008-08-04 17:55:35 +0100180 * Set a new heartbeat value for the watchdog device. If the heartbeat
181 * value is incorrect we keep the old value and return -EINVAL. If
182 * successful we return 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700183 */
Alan Cox9f2d1f02008-08-04 17:55:35 +0100184
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185static int wdt_set_heartbeat(int t)
186{
Alan Cox9f2d1f02008-08-04 17:55:35 +0100187 if (t < 1 || t > 65535)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 return -EINVAL;
189
190 heartbeat = t;
191 wd_heartbeat = t * 100;
192 return 0;
193}
194
195/**
196 * wdt_get_status:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197 *
198 * Extract the status information from a WDT watchdog device. There are
199 * several board variants so we have to know which bits are valid. Some
200 * bits default to one and some to zero in order to be maximally painful.
201 *
202 * we then map the bits onto the status ioctl flags.
203 */
204
Alan Cox04bedfa2009-03-22 10:46:42 +0000205static int wdt_get_status(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700206{
Alan Cox01c785d2008-01-09 21:36:01 -0800207 unsigned char new_status;
Alan Cox04bedfa2009-03-22 10:46:42 +0000208 int status = 0;
Alan Cox01c785d2008-01-09 21:36:01 -0800209 unsigned long flags;
210
211 spin_lock_irqsave(&wdt_lock, flags);
212 new_status = inb_p(WDT_SR);
213 spin_unlock_irqrestore(&wdt_lock, flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 if (new_status & WDC_SR_ISOI0)
Alan Cox04bedfa2009-03-22 10:46:42 +0000216 status |= WDIOF_EXTERN1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217 if (new_status & WDC_SR_ISII1)
Alan Cox04bedfa2009-03-22 10:46:42 +0000218 status |= WDIOF_EXTERN2;
219 if (type == 501) {
220 if (!(new_status & WDC_SR_TGOOD))
221 status |= WDIOF_OVERHEAT;
222 if (!(new_status & WDC_SR_PSUOVER))
223 status |= WDIOF_POWEROVER;
224 if (!(new_status & WDC_SR_PSUUNDR))
225 status |= WDIOF_POWERUNDER;
226 if (tachometer) {
227 if (!(new_status & WDC_SR_FANGOOD))
228 status |= WDIOF_FANFAULT;
229 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700230 }
Alan Cox04bedfa2009-03-22 10:46:42 +0000231 return status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232}
233
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234/**
235 * wdt_get_temperature:
236 *
237 * Reports the temperature in degrees Fahrenheit. The API is in
238 * farenheit. It was designed by an imperial measurement luddite.
239 */
240
Alan Cox04bedfa2009-03-22 10:46:42 +0000241static int wdt_get_temperature(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242{
Alan Cox01c785d2008-01-09 21:36:01 -0800243 unsigned short c;
244 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700245
Alan Cox01c785d2008-01-09 21:36:01 -0800246 spin_lock_irqsave(&wdt_lock, flags);
247 c = inb_p(WDT_RT);
248 spin_unlock_irqrestore(&wdt_lock, flags);
Alan Cox04bedfa2009-03-22 10:46:42 +0000249 return (c * 11 / 15) + 7;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250}
Alan Cox04bedfa2009-03-22 10:46:42 +0000251
252static void wdt_decode_501(int status)
253{
254 if (!(status & WDC_SR_TGOOD))
255 printk(KERN_CRIT "Overheat alarm.(%d)\n", inb_p(WDT_RT));
256 if (!(status & WDC_SR_PSUOVER))
257 printk(KERN_CRIT "PSU over voltage.\n");
258 if (!(status & WDC_SR_PSUUNDR))
259 printk(KERN_CRIT "PSU under voltage.\n");
260}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
262/**
263 * wdt_interrupt:
264 * @irq: Interrupt number
265 * @dev_id: Unused as we don't allow multiple devices.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700266 *
267 * Handle an interrupt from the board. These are raised when the status
268 * map changes in what the board considers an interesting way. That means
269 * a failure condition occurring.
270 */
271
David Howells7d12e782006-10-05 14:55:46 +0100272static irqreturn_t wdt_interrupt(int irq, void *dev_id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273{
274 /*
275 * Read the status register see what is up and
276 * then printk it.
277 */
Alan Cox01c785d2008-01-09 21:36:01 -0800278 unsigned char status;
279
280 spin_lock(&wdt_lock);
281 status = inb_p(WDT_SR);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700282
283 printk(KERN_CRIT "WDT status %d\n", status);
284
Alan Cox04bedfa2009-03-22 10:46:42 +0000285 if (type == 501) {
286 wdt_decode_501(status);
287 if (tachometer) {
288 if (!(status & WDC_SR_FANGOOD))
289 printk(KERN_CRIT "Possible fan fault.\n");
290 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700291 }
Ilpo Jarvinen59338d42007-10-23 13:40:54 -0700292 if (!(status & WDC_SR_WCCR)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293#ifdef SOFTWARE_REBOOT
294#ifdef ONLY_TESTING
295 printk(KERN_CRIT "Would Reboot.\n");
296#else
297 printk(KERN_CRIT "Initiating system reboot.\n");
Eric W. Biedermanf82567e2005-07-26 11:53:19 -0600298 emergency_restart();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299#endif
300#else
301 printk(KERN_CRIT "Reset in 5ms.\n");
302#endif
Ilpo Jarvinen59338d42007-10-23 13:40:54 -0700303 }
Alan Cox01c785d2008-01-09 21:36:01 -0800304 spin_unlock(&wdt_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700305 return IRQ_HANDLED;
306}
307
308
309/**
310 * wdt_write:
311 * @file: file handle to the watchdog
312 * @buf: buffer to write (unused as data does not matter here
313 * @count: count of bytes
314 * @ppos: pointer to the position to write. No seeks allowed
315 *
316 * A write to a watchdog device is defined as a keepalive signal. Any
317 * write of data will do, as we we don't define content meaning.
318 */
319
Alan Cox9f2d1f02008-08-04 17:55:35 +0100320static ssize_t wdt_write(struct file *file, const char __user *buf,
321 size_t count, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322{
Alan Cox9f2d1f02008-08-04 17:55:35 +0100323 if (count) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700324 if (!nowayout) {
325 size_t i;
326
327 /* In case it was set long ago */
328 expect_close = 0;
329
330 for (i = 0; i != count; i++) {
331 char c;
332 if (get_user(c, buf + i))
333 return -EFAULT;
334 if (c == 'V')
335 expect_close = 42;
336 }
337 }
338 wdt_ping();
339 }
340 return count;
341}
342
343/**
344 * wdt_ioctl:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700345 * @file: file handle to the device
346 * @cmd: watchdog command
347 * @arg: argument pointer
348 *
349 * The watchdog API defines a common set of functions for all watchdogs
350 * according to their available features. We only actually usefully support
351 * querying capabilities and current status.
352 */
353
Alan Cox9f2d1f02008-08-04 17:55:35 +0100354static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355{
356 void __user *argp = (void __user *)arg;
357 int __user *p = argp;
358 int new_heartbeat;
359 int status;
360
Andrew Mortonc1bf3ac2010-03-03 11:57:40 -0800361 struct watchdog_info ident = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700362 .options = WDIOF_SETTIMEOUT|
363 WDIOF_MAGICCLOSE|
364 WDIOF_KEEPALIVEPING,
365 .firmware_version = 1,
366 .identity = "WDT500/501",
367 };
368
369 /* Add options according to the card we have */
370 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
Alan Cox04bedfa2009-03-22 10:46:42 +0000371 if (type == 501) {
372 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|
373 WDIOF_POWEROVER);
374 if (tachometer)
375 ident.options |= WDIOF_FANFAULT;
376 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
Alan Cox9f2d1f02008-08-04 17:55:35 +0100378 switch (cmd) {
Alan Cox9f2d1f02008-08-04 17:55:35 +0100379 case WDIOC_GETSUPPORT:
380 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
381 case WDIOC_GETSTATUS:
Alan Cox04bedfa2009-03-22 10:46:42 +0000382 status = wdt_get_status();
Alan Cox9f2d1f02008-08-04 17:55:35 +0100383 return put_user(status, p);
384 case WDIOC_GETBOOTSTATUS:
385 return put_user(0, p);
386 case WDIOC_KEEPALIVE:
387 wdt_ping();
388 return 0;
389 case WDIOC_SETTIMEOUT:
390 if (get_user(new_heartbeat, p))
391 return -EFAULT;
392 if (wdt_set_heartbeat(new_heartbeat))
393 return -EINVAL;
394 wdt_ping();
395 /* Fall */
396 case WDIOC_GETTIMEOUT:
397 return put_user(heartbeat, p);
Wim Van Sebroeck0c060902008-07-18 11:41:17 +0000398 default:
399 return -ENOTTY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700400 }
401}
402
403/**
404 * wdt_open:
405 * @inode: inode of device
406 * @file: file handle to device
407 *
408 * The watchdog device has been opened. The watchdog device is single
409 * open and on opening we load the counters. Counter zero is a 100Hz
410 * cascade, into counter 1 which downcounts to reboot. When the counter
411 * triggers counter 2 downcounts the length of the reset pulse which
412 * set set to be as long as possible.
413 */
414
415static int wdt_open(struct inode *inode, struct file *file)
416{
Alan Cox9f2d1f02008-08-04 17:55:35 +0100417 if (test_and_set_bit(0, &wdt_is_open))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418 return -EBUSY;
419 /*
420 * Activate
421 */
422 wdt_start();
423 return nonseekable_open(inode, file);
424}
425
426/**
427 * wdt_release:
428 * @inode: inode to board
429 * @file: file handle to board
430 *
431 * The watchdog has a configurable API. There is a religious dispute
432 * between people who want their watchdog to be able to shut down and
433 * those who want to be sure if the watchdog manager dies the machine
434 * reboots. In the former case we disable the counters, in the latter
435 * case you have to open it again very soon.
436 */
437
438static int wdt_release(struct inode *inode, struct file *file)
439{
440 if (expect_close == 42) {
441 wdt_stop();
442 clear_bit(0, &wdt_is_open);
443 } else {
Alan Cox9f2d1f02008-08-04 17:55:35 +0100444 printk(KERN_CRIT
445 "wdt: WDT device closed unexpectedly. WDT will not stop!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 wdt_ping();
447 }
448 expect_close = 0;
449 return 0;
450}
451
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452/**
453 * wdt_temp_read:
454 * @file: file handle to the watchdog board
455 * @buf: buffer to write 1 byte into
456 * @count: length of buffer
457 * @ptr: offset (no seek allowed)
458 *
459 * Temp_read reports the temperature in degrees Fahrenheit. The API is in
460 * farenheit. It was designed by an imperial measurement luddite.
461 */
462
Alan Cox9f2d1f02008-08-04 17:55:35 +0100463static ssize_t wdt_temp_read(struct file *file, char __user *buf,
464 size_t count, loff_t *ptr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465{
Alan Cox04bedfa2009-03-22 10:46:42 +0000466 int temperature = wdt_get_temperature();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467
Alan Cox9f2d1f02008-08-04 17:55:35 +0100468 if (copy_to_user(buf, &temperature, 1))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 return -EFAULT;
470
471 return 1;
472}
473
474/**
475 * wdt_temp_open:
476 * @inode: inode of device
477 * @file: file handle to device
478 *
479 * The temperature device has been opened.
480 */
481
482static int wdt_temp_open(struct inode *inode, struct file *file)
483{
484 return nonseekable_open(inode, file);
485}
486
487/**
488 * wdt_temp_release:
489 * @inode: inode to board
490 * @file: file handle to board
491 *
492 * The temperature device has been closed.
493 */
494
495static int wdt_temp_release(struct inode *inode, struct file *file)
496{
497 return 0;
498}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499
500/**
501 * notify_sys:
502 * @this: our notifier block
503 * @code: the event being reported
504 * @unused: unused
505 *
506 * Our notifier is called on system shutdowns. We want to turn the card
507 * off at reboot otherwise the machine will reboot again during memory
508 * test or worse yet during the following fsck. This would suck, in fact
509 * trust me - if it happens it does suck.
510 */
511
512static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
513 void *unused)
514{
Alan Cox9f2d1f02008-08-04 17:55:35 +0100515 if (code == SYS_DOWN || code == SYS_HALT)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516 wdt_stop();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517 return NOTIFY_DONE;
518}
519
520/*
521 * Kernel Interfaces
522 */
523
524
Arjan van de Ven62322d22006-07-03 00:24:21 -0700525static const struct file_operations wdt_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 .owner = THIS_MODULE,
527 .llseek = no_llseek,
528 .write = wdt_write,
Alan Cox9f2d1f02008-08-04 17:55:35 +0100529 .unlocked_ioctl = wdt_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 .open = wdt_open,
531 .release = wdt_release,
532};
533
534static struct miscdevice wdt_miscdev = {
535 .minor = WATCHDOG_MINOR,
536 .name = "watchdog",
537 .fops = &wdt_fops,
538};
539
Arjan van de Ven62322d22006-07-03 00:24:21 -0700540static const struct file_operations wdt_temp_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541 .owner = THIS_MODULE,
542 .llseek = no_llseek,
543 .read = wdt_temp_read,
544 .open = wdt_temp_open,
545 .release = wdt_temp_release,
546};
547
548static struct miscdevice temp_miscdev = {
549 .minor = TEMP_MINOR,
550 .name = "temperature",
551 .fops = &wdt_temp_fops,
552};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700553
554/*
555 * The WDT card needs to learn about soft shutdowns in order to
556 * turn the timebomb registers off.
557 */
558
559static struct notifier_block wdt_notifier = {
560 .notifier_call = wdt_notify_sys,
561};
562
563/**
564 * cleanup_module:
565 *
566 * Unload the watchdog. You cannot do this with any file handles open.
567 * If your watchdog is set to continue ticking on close and you unload
568 * it, well it keeps ticking. We won't get the interrupt but the board
569 * will not touch PC memory so all is fine. You just have to load a new
570 * module in 60 seconds or reboot.
571 */
572
573static void __exit wdt_exit(void)
574{
575 misc_deregister(&wdt_miscdev);
Alan Cox04bedfa2009-03-22 10:46:42 +0000576 if (type == 501)
577 misc_deregister(&temp_miscdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 unregister_reboot_notifier(&wdt_notifier);
579 free_irq(irq, NULL);
Alan Cox9f2d1f02008-08-04 17:55:35 +0100580 release_region(io, 8);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581}
582
583/**
Wim Van Sebroeck5f3b2752011-02-23 20:04:38 +0000584 * wdt_init:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585 *
586 * Set up the WDT watchdog board. All we have to do is grab the
587 * resources we require and bitch if anyone beat us to them.
588 * The open() function will actually kick the board off.
589 */
590
591static int __init wdt_init(void)
592{
593 int ret;
594
Alan Cox04bedfa2009-03-22 10:46:42 +0000595 if (type != 500 && type != 501) {
596 printk(KERN_ERR "wdt: unknown card type '%d'.\n", type);
597 return -ENODEV;
598 }
599
Alan Cox9f2d1f02008-08-04 17:55:35 +0100600 /* Check that the heartbeat value is within it's range;
601 if not reset to the default */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 if (wdt_set_heartbeat(heartbeat)) {
603 wdt_set_heartbeat(WD_TIMO);
Alan Cox04bedfa2009-03-22 10:46:42 +0000604 printk(KERN_INFO "wdt: heartbeat value must be "
605 "0 < heartbeat < 65536, using %d\n", WD_TIMO);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 }
607
608 if (!request_region(io, 8, "wdt501p")) {
Alan Cox9f2d1f02008-08-04 17:55:35 +0100609 printk(KERN_ERR
610 "wdt: I/O address 0x%04x already in use\n", io);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 ret = -EBUSY;
612 goto out;
613 }
614
Thomas Gleixner0f2ed4c2006-07-01 19:29:33 -0700615 ret = request_irq(irq, wdt_interrupt, IRQF_DISABLED, "wdt501p", NULL);
Alan Cox9f2d1f02008-08-04 17:55:35 +0100616 if (ret) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700617 printk(KERN_ERR "wdt: IRQ %d is not free.\n", irq);
618 goto outreg;
619 }
620
621 ret = register_reboot_notifier(&wdt_notifier);
Alan Cox9f2d1f02008-08-04 17:55:35 +0100622 if (ret) {
623 printk(KERN_ERR
624 "wdt: cannot register reboot notifier (err=%d)\n", ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 goto outirq;
626 }
627
Alan Cox04bedfa2009-03-22 10:46:42 +0000628 if (type == 501) {
629 ret = misc_register(&temp_miscdev);
630 if (ret) {
631 printk(KERN_ERR "wdt: cannot register miscdev "
632 "on minor=%d (err=%d)\n", TEMP_MINOR, ret);
633 goto outrbt;
634 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636
637 ret = misc_register(&wdt_miscdev);
638 if (ret) {
Alan Cox9f2d1f02008-08-04 17:55:35 +0100639 printk(KERN_ERR
640 "wdt: cannot register miscdev on minor=%d (err=%d)\n",
641 WATCHDOG_MINOR, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 goto outmisc;
643 }
644
Alan Cox04bedfa2009-03-22 10:46:42 +0000645 printk(KERN_INFO "WDT500/501-P driver 0.10 "
646 "at 0x%04x (Interrupt %d). heartbeat=%d sec (nowayout=%d)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 io, irq, heartbeat, nowayout);
Alan Cox04bedfa2009-03-22 10:46:42 +0000648 if (type == 501)
649 printk(KERN_INFO "wdt: Fan Tachometer is %s\n",
Alan Cox9f2d1f02008-08-04 17:55:35 +0100650 (tachometer ? "Enabled" : "Disabled"));
Alan Cox04bedfa2009-03-22 10:46:42 +0000651 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652
653outmisc:
Alan Cox04bedfa2009-03-22 10:46:42 +0000654 if (type == 501)
655 misc_deregister(&temp_miscdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656outrbt:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657 unregister_reboot_notifier(&wdt_notifier);
658outirq:
659 free_irq(irq, NULL);
660outreg:
Alan Cox9f2d1f02008-08-04 17:55:35 +0100661 release_region(io, 8);
Alan Cox04bedfa2009-03-22 10:46:42 +0000662out:
663 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664}
665
666module_init(wdt_init);
667module_exit(wdt_exit);
668
669MODULE_AUTHOR("Alan Cox");
670MODULE_DESCRIPTION("Driver for ISA ICS watchdog cards (WDT500/501)");
671MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
672MODULE_ALIAS_MISCDEV(TEMP_MINOR);
673MODULE_LICENSE("GPL");