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