xref: /openbmc/linux/drivers/watchdog/wdt_pci.c (revision a09d2831)
1 /*
2  *	Industrial Computer Source PCI-WDT500/501 driver
3  *
4  *	(c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>,
5  *						All Rights Reserved.
6  *
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
27  *		Tim Hockin	:	Added insmod parameters, comment cleanup
28  *					Parameterized timeout
29  *		JP Nollmann	:	Added support for PCI wdt501p
30  *		Alan Cox	:	Split ISA and PCI cards into two drivers
31  *		Jeff Garzik	:	PCI cleanups
32  *		Tigran Aivazian	:	Restructured wdtpci_init_one() to handle
33  *					failures
34  *		Joel Becker 	:	Added WDIOC_GET/SETTIMEOUT
35  *		Zwane Mwaikambo	:	Magic char closing, locking changes,
36  *					cleanups
37  *		Matt Domsch	:	nowayout module option
38  */
39 
40 #include <linux/interrupt.h>
41 #include <linux/module.h>
42 #include <linux/moduleparam.h>
43 #include <linux/types.h>
44 #include <linux/miscdevice.h>
45 #include <linux/watchdog.h>
46 #include <linux/ioport.h>
47 #include <linux/delay.h>
48 #include <linux/notifier.h>
49 #include <linux/reboot.h>
50 #include <linux/init.h>
51 #include <linux/fs.h>
52 #include <linux/pci.h>
53 #include <linux/io.h>
54 #include <linux/uaccess.h>
55 
56 #include <asm/system.h>
57 
58 #define WDT_IS_PCI
59 #include "wd501p.h"
60 
61 #define PFX "wdt_pci: "
62 
63 /*
64  * Until Access I/O gets their application for a PCI vendor ID approved,
65  * I don't think that it's appropriate to move these constants into the
66  * regular pci_ids.h file. -- JPN 2000/01/18
67  */
68 
69 #ifndef PCI_VENDOR_ID_ACCESSIO
70 #define PCI_VENDOR_ID_ACCESSIO 0x494f
71 #endif
72 #ifndef PCI_DEVICE_ID_WDG_CSM
73 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
74 #endif
75 
76 /* We can only use 1 card due to the /dev/watchdog restriction */
77 static int dev_count;
78 
79 static unsigned long open_lock;
80 static DEFINE_SPINLOCK(wdtpci_lock);
81 static char expect_close;
82 
83 static resource_size_t io;
84 static int irq;
85 
86 /* Default timeout */
87 #define WD_TIMO 60			/* Default heartbeat = 60 seconds */
88 
89 static int heartbeat = WD_TIMO;
90 static int wd_heartbeat;
91 module_param(heartbeat, int, 0);
92 MODULE_PARM_DESC(heartbeat,
93 		"Watchdog heartbeat in seconds. (0<heartbeat<65536, default="
94 				__MODULE_STRING(WD_TIMO) ")");
95 
96 static int nowayout = WATCHDOG_NOWAYOUT;
97 module_param(nowayout, int, 0);
98 MODULE_PARM_DESC(nowayout,
99 		"Watchdog cannot be stopped once started (default="
100 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
101 
102 /* Support for the Fan Tachometer on the PCI-WDT501 */
103 static int tachometer;
104 module_param(tachometer, int, 0);
105 MODULE_PARM_DESC(tachometer,
106 		"PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
107 
108 static int type = 500;
109 module_param(type, int, 0);
110 MODULE_PARM_DESC(type,
111 		"PCI-WDT501 Card type (500 or 501 , default=500)");
112 
113 /*
114  *	Programming support
115  */
116 
117 static void wdtpci_ctr_mode(int ctr, int mode)
118 {
119 	ctr <<= 6;
120 	ctr |= 0x30;
121 	ctr |= (mode << 1);
122 	outb(ctr, WDT_CR);
123 	udelay(8);
124 }
125 
126 static void wdtpci_ctr_load(int ctr, int val)
127 {
128 	outb(val & 0xFF, WDT_COUNT0 + ctr);
129 	udelay(8);
130 	outb(val >> 8, WDT_COUNT0 + ctr);
131 	udelay(8);
132 }
133 
134 /**
135  *	wdtpci_start:
136  *
137  *	Start the watchdog driver.
138  */
139 
140 static int wdtpci_start(void)
141 {
142 	unsigned long flags;
143 
144 	spin_lock_irqsave(&wdtpci_lock, flags);
145 
146 	/*
147 	 * "pet" the watchdog, as Access says.
148 	 * This resets the clock outputs.
149 	 */
150 	inb(WDT_DC);			/* Disable watchdog */
151 	udelay(8);
152 	wdtpci_ctr_mode(2, 0);		/* Program CTR2 for Mode 0:
153 						Pulse on Terminal Count */
154 	outb(0, WDT_DC);		/* Enable watchdog */
155 	udelay(8);
156 	inb(WDT_DC);			/* Disable watchdog */
157 	udelay(8);
158 	outb(0, WDT_CLOCK);		/* 2.0833MHz clock */
159 	udelay(8);
160 	inb(WDT_BUZZER);		/* disable */
161 	udelay(8);
162 	inb(WDT_OPTONOTRST);		/* disable */
163 	udelay(8);
164 	inb(WDT_OPTORST);		/* disable */
165 	udelay(8);
166 	inb(WDT_PROGOUT);		/* disable */
167 	udelay(8);
168 	wdtpci_ctr_mode(0, 3);		/* Program CTR0 for Mode 3:
169 						Square Wave Generator */
170 	wdtpci_ctr_mode(1, 2);		/* Program CTR1 for Mode 2:
171 						Rate Generator */
172 	wdtpci_ctr_mode(2, 1);		/* Program CTR2 for Mode 1:
173 						Retriggerable One-Shot */
174 	wdtpci_ctr_load(0, 20833);	/* count at 100Hz */
175 	wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
176 	/* DO NOT LOAD CTR2 on PCI card! -- JPN */
177 	outb(0, WDT_DC);		/* Enable watchdog */
178 	udelay(8);
179 
180 	spin_unlock_irqrestore(&wdtpci_lock, flags);
181 	return 0;
182 }
183 
184 /**
185  *	wdtpci_stop:
186  *
187  *	Stop the watchdog driver.
188  */
189 
190 static int wdtpci_stop(void)
191 {
192 	unsigned long flags;
193 
194 	/* Turn the card off */
195 	spin_lock_irqsave(&wdtpci_lock, flags);
196 	inb(WDT_DC);			/* Disable watchdog */
197 	udelay(8);
198 	wdtpci_ctr_load(2, 0);		/* 0 length reset pulses now */
199 	spin_unlock_irqrestore(&wdtpci_lock, flags);
200 	return 0;
201 }
202 
203 /**
204  *	wdtpci_ping:
205  *
206  *	Reload counter one with the watchdog heartbeat. We don't bother
207  *	reloading the cascade counter.
208  */
209 
210 static int wdtpci_ping(void)
211 {
212 	unsigned long flags;
213 
214 	spin_lock_irqsave(&wdtpci_lock, flags);
215 	/* Write a watchdog value */
216 	inb(WDT_DC);			/* Disable watchdog */
217 	udelay(8);
218 	wdtpci_ctr_mode(1, 2);		/* Re-Program CTR1 for Mode 2:
219 							Rate Generator */
220 	wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
221 	outb(0, WDT_DC);		/* Enable watchdog */
222 	udelay(8);
223 	spin_unlock_irqrestore(&wdtpci_lock, flags);
224 	return 0;
225 }
226 
227 /**
228  *	wdtpci_set_heartbeat:
229  *	@t:		the new heartbeat value that needs to be set.
230  *
231  *	Set a new heartbeat value for the watchdog device. If the heartbeat
232  *	value is incorrect we keep the old value and return -EINVAL.
233  *	If successful we return 0.
234  */
235 static int wdtpci_set_heartbeat(int t)
236 {
237 	/* Arbitrary, can't find the card's limits */
238 	if (t < 1 || t > 65535)
239 		return -EINVAL;
240 
241 	heartbeat = t;
242 	wd_heartbeat = t * 100;
243 	return 0;
244 }
245 
246 /**
247  *	wdtpci_get_status:
248  *	@status:		the new status.
249  *
250  *	Extract the status information from a WDT watchdog device. There are
251  *	several board variants so we have to know which bits are valid. Some
252  *	bits default to one and some to zero in order to be maximally painful.
253  *
254  *	we then map the bits onto the status ioctl flags.
255  */
256 
257 static int wdtpci_get_status(int *status)
258 {
259 	unsigned char new_status;
260 	unsigned long flags;
261 
262 	spin_lock_irqsave(&wdtpci_lock, flags);
263 	new_status = inb(WDT_SR);
264 	spin_unlock_irqrestore(&wdtpci_lock, flags);
265 
266 	*status = 0;
267 	if (new_status & WDC_SR_ISOI0)
268 		*status |= WDIOF_EXTERN1;
269 	if (new_status & WDC_SR_ISII1)
270 		*status |= WDIOF_EXTERN2;
271 	if (type == 501) {
272 		if (!(new_status & WDC_SR_TGOOD))
273 			*status |= WDIOF_OVERHEAT;
274 		if (!(new_status & WDC_SR_PSUOVER))
275 			*status |= WDIOF_POWEROVER;
276 		if (!(new_status & WDC_SR_PSUUNDR))
277 			*status |= WDIOF_POWERUNDER;
278 		if (tachometer) {
279 			if (!(new_status & WDC_SR_FANGOOD))
280 				*status |= WDIOF_FANFAULT;
281 		}
282 	}
283 	return 0;
284 }
285 
286 /**
287  *	wdtpci_get_temperature:
288  *
289  *	Reports the temperature in degrees Fahrenheit. The API is in
290  *	farenheit. It was designed by an imperial measurement luddite.
291  */
292 
293 static int wdtpci_get_temperature(int *temperature)
294 {
295 	unsigned short c;
296 	unsigned long flags;
297 	spin_lock_irqsave(&wdtpci_lock, flags);
298 	c = inb(WDT_RT);
299 	udelay(8);
300 	spin_unlock_irqrestore(&wdtpci_lock, flags);
301 	*temperature = (c * 11 / 15) + 7;
302 	return 0;
303 }
304 
305 /**
306  *	wdtpci_interrupt:
307  *	@irq:		Interrupt number
308  *	@dev_id:	Unused as we don't allow multiple devices.
309  *
310  *	Handle an interrupt from the board. These are raised when the status
311  *	map changes in what the board considers an interesting way. That means
312  *	a failure condition occurring.
313  */
314 
315 static irqreturn_t wdtpci_interrupt(int irq, void *dev_id)
316 {
317 	/*
318 	 *	Read the status register see what is up and
319 	 *	then printk it.
320 	 */
321 	unsigned char status;
322 
323 	spin_lock(&wdtpci_lock);
324 
325 	status = inb(WDT_SR);
326 	udelay(8);
327 
328 	printk(KERN_CRIT PFX "status %d\n", status);
329 
330 	if (type == 501) {
331 		if (!(status & WDC_SR_TGOOD)) {
332 			printk(KERN_CRIT PFX "Overheat alarm.(%d)\n",
333 								inb(WDT_RT));
334 			udelay(8);
335 		}
336 		if (!(status & WDC_SR_PSUOVER))
337 			printk(KERN_CRIT PFX "PSU over voltage.\n");
338 		if (!(status & WDC_SR_PSUUNDR))
339 			printk(KERN_CRIT PFX "PSU under voltage.\n");
340 		if (tachometer) {
341 			if (!(status & WDC_SR_FANGOOD))
342 				printk(KERN_CRIT PFX "Possible fan fault.\n");
343 		}
344 	}
345 	if (!(status & WDC_SR_WCCR)) {
346 #ifdef SOFTWARE_REBOOT
347 #ifdef ONLY_TESTING
348 		printk(KERN_CRIT PFX "Would Reboot.\n");
349 #else
350 		printk(KERN_CRIT PFX "Initiating system reboot.\n");
351 		emergency_restart(NULL);
352 #endif
353 #else
354 		printk(KERN_CRIT PFX "Reset in 5ms.\n");
355 #endif
356 	}
357 	spin_unlock(&wdtpci_lock);
358 	return IRQ_HANDLED;
359 }
360 
361 
362 /**
363  *	wdtpci_write:
364  *	@file: file handle to the watchdog
365  *	@buf: buffer to write (unused as data does not matter here
366  *	@count: count of bytes
367  *	@ppos: pointer to the position to write. No seeks allowed
368  *
369  *	A write to a watchdog device is defined as a keepalive signal. Any
370  *	write of data will do, as we we don't define content meaning.
371  */
372 
373 static ssize_t wdtpci_write(struct file *file, const char __user *buf,
374 						size_t count, loff_t *ppos)
375 {
376 	if (count) {
377 		if (!nowayout) {
378 			size_t i;
379 
380 			/* In case it was set long ago */
381 			expect_close = 0;
382 
383 			for (i = 0; i != count; i++) {
384 				char c;
385 				if (get_user(c, buf + i))
386 					return -EFAULT;
387 				if (c == 'V')
388 					expect_close = 42;
389 			}
390 		}
391 		wdtpci_ping();
392 	}
393 	return count;
394 }
395 
396 /**
397  *	wdtpci_ioctl:
398  *	@file: file handle to the device
399  *	@cmd: watchdog command
400  *	@arg: argument pointer
401  *
402  *	The watchdog API defines a common set of functions for all watchdogs
403  *	according to their available features. We only actually usefully support
404  *	querying capabilities and current status.
405  */
406 
407 static long wdtpci_ioctl(struct file *file, unsigned int cmd,
408 							unsigned long arg)
409 {
410 	void __user *argp = (void __user *)arg;
411 	int __user *p = argp;
412 	int new_heartbeat;
413 	int status;
414 
415 	static struct watchdog_info ident = {
416 		.options =		WDIOF_SETTIMEOUT|
417 					WDIOF_MAGICCLOSE|
418 					WDIOF_KEEPALIVEPING,
419 		.firmware_version =	1,
420 		.identity =		"PCI-WDT500/501",
421 	};
422 
423 	/* Add options according to the card we have */
424 	ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
425 	if (type == 501) {
426 		ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|
427 							WDIOF_POWEROVER);
428 		if (tachometer)
429 			ident.options |= WDIOF_FANFAULT;
430 	}
431 
432 	switch (cmd) {
433 	case WDIOC_GETSUPPORT:
434 		return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
435 	case WDIOC_GETSTATUS:
436 		wdtpci_get_status(&status);
437 		return put_user(status, p);
438 	case WDIOC_GETBOOTSTATUS:
439 		return put_user(0, p);
440 	case WDIOC_KEEPALIVE:
441 		wdtpci_ping();
442 		return 0;
443 	case WDIOC_SETTIMEOUT:
444 		if (get_user(new_heartbeat, p))
445 			return -EFAULT;
446 		if (wdtpci_set_heartbeat(new_heartbeat))
447 			return -EINVAL;
448 		wdtpci_ping();
449 		/* Fall */
450 	case WDIOC_GETTIMEOUT:
451 		return put_user(heartbeat, p);
452 	default:
453 		return -ENOTTY;
454 	}
455 }
456 
457 /**
458  *	wdtpci_open:
459  *	@inode: inode of device
460  *	@file: file handle to device
461  *
462  *	The watchdog device has been opened. The watchdog device is single
463  *	open and on opening we load the counters. Counter zero is a 100Hz
464  *	cascade, into counter 1 which downcounts to reboot. When the counter
465  *	triggers counter 2 downcounts the length of the reset pulse which
466  *	set set to be as long as possible.
467  */
468 
469 static int wdtpci_open(struct inode *inode, struct file *file)
470 {
471 	if (test_and_set_bit(0, &open_lock))
472 		return -EBUSY;
473 
474 	if (nowayout)
475 		__module_get(THIS_MODULE);
476 	/*
477 	 *	Activate
478 	 */
479 	wdtpci_start();
480 	return nonseekable_open(inode, file);
481 }
482 
483 /**
484  *	wdtpci_release:
485  *	@inode: inode to board
486  *	@file: file handle to board
487  *
488  *	The watchdog has a configurable API. There is a religious dispute
489  *	between people who want their watchdog to be able to shut down and
490  *	those who want to be sure if the watchdog manager dies the machine
491  *	reboots. In the former case we disable the counters, in the latter
492  *	case you have to open it again very soon.
493  */
494 
495 static int wdtpci_release(struct inode *inode, struct file *file)
496 {
497 	if (expect_close == 42) {
498 		wdtpci_stop();
499 	} else {
500 		printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
501 		wdtpci_ping();
502 	}
503 	expect_close = 0;
504 	clear_bit(0, &open_lock);
505 	return 0;
506 }
507 
508 /**
509  *	wdtpci_temp_read:
510  *	@file: file handle to the watchdog board
511  *	@buf: buffer to write 1 byte into
512  *	@count: length of buffer
513  *	@ptr: offset (no seek allowed)
514  *
515  *	Read reports the temperature in degrees Fahrenheit. The API is in
516  *	fahrenheit. It was designed by an imperial measurement luddite.
517  */
518 
519 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf,
520 						size_t count, loff_t *ptr)
521 {
522 	int temperature;
523 
524 	if (wdtpci_get_temperature(&temperature))
525 		return -EFAULT;
526 
527 	if (copy_to_user(buf, &temperature, 1))
528 		return -EFAULT;
529 
530 	return 1;
531 }
532 
533 /**
534  *	wdtpci_temp_open:
535  *	@inode: inode of device
536  *	@file: file handle to device
537  *
538  *	The temperature device has been opened.
539  */
540 
541 static int wdtpci_temp_open(struct inode *inode, struct file *file)
542 {
543 	return nonseekable_open(inode, file);
544 }
545 
546 /**
547  *	wdtpci_temp_release:
548  *	@inode: inode to board
549  *	@file: file handle to board
550  *
551  *	The temperature device has been closed.
552  */
553 
554 static int wdtpci_temp_release(struct inode *inode, struct file *file)
555 {
556 	return 0;
557 }
558 
559 /**
560  *	notify_sys:
561  *	@this: our notifier block
562  *	@code: the event being reported
563  *	@unused: unused
564  *
565  *	Our notifier is called on system shutdowns. We want to turn the card
566  *	off at reboot otherwise the machine will reboot again during memory
567  *	test or worse yet during the following fsck. This would suck, in fact
568  *	trust me - if it happens it does suck.
569  */
570 
571 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
572 							void *unused)
573 {
574 	if (code == SYS_DOWN || code == SYS_HALT)
575 		wdtpci_stop();
576 	return NOTIFY_DONE;
577 }
578 
579 /*
580  *	Kernel Interfaces
581  */
582 
583 
584 static const struct file_operations wdtpci_fops = {
585 	.owner		= THIS_MODULE,
586 	.llseek		= no_llseek,
587 	.write		= wdtpci_write,
588 	.unlocked_ioctl	= wdtpci_ioctl,
589 	.open		= wdtpci_open,
590 	.release	= wdtpci_release,
591 };
592 
593 static struct miscdevice wdtpci_miscdev = {
594 	.minor	= WATCHDOG_MINOR,
595 	.name	= "watchdog",
596 	.fops	= &wdtpci_fops,
597 };
598 
599 static const struct file_operations wdtpci_temp_fops = {
600 	.owner		= THIS_MODULE,
601 	.llseek		= no_llseek,
602 	.read		= wdtpci_temp_read,
603 	.open		= wdtpci_temp_open,
604 	.release	= wdtpci_temp_release,
605 };
606 
607 static struct miscdevice temp_miscdev = {
608 	.minor	= TEMP_MINOR,
609 	.name	= "temperature",
610 	.fops	= &wdtpci_temp_fops,
611 };
612 
613 /*
614  *	The WDT card needs to learn about soft shutdowns in order to
615  *	turn the timebomb registers off.
616  */
617 
618 static struct notifier_block wdtpci_notifier = {
619 	.notifier_call = wdtpci_notify_sys,
620 };
621 
622 
623 static int __devinit wdtpci_init_one(struct pci_dev *dev,
624 					const struct pci_device_id *ent)
625 {
626 	int ret = -EIO;
627 
628 	dev_count++;
629 	if (dev_count > 1) {
630 		printk(KERN_ERR PFX "This driver only supports one device\n");
631 		return -ENODEV;
632 	}
633 
634 	if (type != 500 && type != 501) {
635 		printk(KERN_ERR PFX "unknown card type '%d'.\n", type);
636 		return -ENODEV;
637 	}
638 
639 	if (pci_enable_device(dev)) {
640 		printk(KERN_ERR PFX "Not possible to enable PCI Device\n");
641 		return -ENODEV;
642 	}
643 
644 	if (pci_resource_start(dev, 2) == 0x0000) {
645 		printk(KERN_ERR PFX "No I/O-Address for card detected\n");
646 		ret = -ENODEV;
647 		goto out_pci;
648 	}
649 
650 	if (pci_request_region(dev, 2, "wdt_pci")) {
651 		printk(KERN_ERR PFX "I/O address 0x%llx already in use\n",
652 			(unsigned long long)pci_resource_start(dev, 2));
653 		goto out_pci;
654 	}
655 
656 	irq = dev->irq;
657 	io = pci_resource_start(dev, 2);
658 
659 	if (request_irq(irq, wdtpci_interrupt, IRQF_DISABLED | IRQF_SHARED,
660 			 "wdt_pci", &wdtpci_miscdev)) {
661 		printk(KERN_ERR PFX "IRQ %d is not free\n", irq);
662 		goto out_reg;
663 	}
664 
665 	printk(KERN_INFO
666 	 "PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%llx (Interrupt %d)\n",
667 					(unsigned long long)io, irq);
668 
669 	/* Check that the heartbeat value is within its range;
670 	   if not reset to the default */
671 	if (wdtpci_set_heartbeat(heartbeat)) {
672 		wdtpci_set_heartbeat(WD_TIMO);
673 		printk(KERN_INFO PFX
674 		  "heartbeat value must be 0 < heartbeat < 65536, using %d\n",
675 								WD_TIMO);
676 	}
677 
678 	ret = register_reboot_notifier(&wdtpci_notifier);
679 	if (ret) {
680 		printk(KERN_ERR PFX
681 			"cannot register reboot notifier (err=%d)\n", ret);
682 		goto out_irq;
683 	}
684 
685 	if (type == 501) {
686 		ret = misc_register(&temp_miscdev);
687 		if (ret) {
688 			printk(KERN_ERR PFX
689 			"cannot register miscdev on minor=%d (err=%d)\n",
690 							TEMP_MINOR, ret);
691 			goto out_rbt;
692 		}
693 	}
694 
695 	ret = misc_register(&wdtpci_miscdev);
696 	if (ret) {
697 		printk(KERN_ERR PFX
698 			"cannot register miscdev on minor=%d (err=%d)\n",
699 						WATCHDOG_MINOR, ret);
700 		goto out_misc;
701 	}
702 
703 	printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
704 		heartbeat, nowayout);
705 	if (type == 501)
706 		printk(KERN_INFO "wdt: Fan Tachometer is %s\n",
707 				(tachometer ? "Enabled" : "Disabled"));
708 
709 	ret = 0;
710 out:
711 	return ret;
712 
713 out_misc:
714 	if (type == 501)
715 		misc_deregister(&temp_miscdev);
716 out_rbt:
717 	unregister_reboot_notifier(&wdtpci_notifier);
718 out_irq:
719 	free_irq(irq, &wdtpci_miscdev);
720 out_reg:
721 	pci_release_region(dev, 2);
722 out_pci:
723 	pci_disable_device(dev);
724 	goto out;
725 }
726 
727 
728 static void __devexit wdtpci_remove_one(struct pci_dev *pdev)
729 {
730 	/* here we assume only one device will ever have
731 	 * been picked up and registered by probe function */
732 	misc_deregister(&wdtpci_miscdev);
733 	if (type == 501)
734 		misc_deregister(&temp_miscdev);
735 	unregister_reboot_notifier(&wdtpci_notifier);
736 	free_irq(irq, &wdtpci_miscdev);
737 	pci_release_region(pdev, 2);
738 	pci_disable_device(pdev);
739 	dev_count--;
740 }
741 
742 
743 static struct pci_device_id wdtpci_pci_tbl[] = {
744 	{
745 		.vendor	   = PCI_VENDOR_ID_ACCESSIO,
746 		.device	   = PCI_DEVICE_ID_WDG_CSM,
747 		.subvendor = PCI_ANY_ID,
748 		.subdevice = PCI_ANY_ID,
749 	},
750 	{ 0, }, /* terminate list */
751 };
752 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
753 
754 
755 static struct pci_driver wdtpci_driver = {
756 	.name		= "wdt_pci",
757 	.id_table	= wdtpci_pci_tbl,
758 	.probe		= wdtpci_init_one,
759 	.remove		= __devexit_p(wdtpci_remove_one),
760 };
761 
762 
763 /**
764  *	wdtpci_cleanup:
765  *
766  *	Unload the watchdog. You cannot do this with any file handles open.
767  *	If your watchdog is set to continue ticking on close and you unload
768  *	it, well it keeps ticking. We won't get the interrupt but the board
769  *	will not touch PC memory so all is fine. You just have to load a new
770  *	module in xx seconds or reboot.
771  */
772 
773 static void __exit wdtpci_cleanup(void)
774 {
775 	pci_unregister_driver(&wdtpci_driver);
776 }
777 
778 
779 /**
780  * 	wdtpci_init:
781  *
782  *	Set up the WDT watchdog board. All we have to do is grab the
783  *	resources we require and bitch if anyone beat us to them.
784  *	The open() function will actually kick the board off.
785  */
786 
787 static int __init wdtpci_init(void)
788 {
789 	return pci_register_driver(&wdtpci_driver);
790 }
791 
792 
793 module_init(wdtpci_init);
794 module_exit(wdtpci_cleanup);
795 
796 MODULE_AUTHOR("JP Nollmann, Alan Cox");
797 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
798 MODULE_LICENSE("GPL");
799 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
800 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
801