2 * Industrial Computer Source PCI-WDT500/501 driver
4 * (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved.
5 * http://www.redhat.com
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.
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.
16 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
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
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
34 * Joel Becker : Added WDIOC_GET/SETTIMEOUT
35 * Zwane Mwaikambo : Magic char closing, locking changes,
37 * Matt Domsch : nowayout module option
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/notifier.h>
48 #include <linux/reboot.h>
49 #include <linux/init.h>
51 #include <linux/pci.h>
53 #include <linux/uaccess.h>
55 #include <asm/system.h>
60 #define PFX "wdt_pci: "
63 * Until Access I/O gets their application for a PCI vendor ID approved,
64 * I don't think that it's appropriate to move these constants into the
65 * regular pci_ids.h file. -- JPN 2000/01/18
68 #ifndef PCI_VENDOR_ID_ACCESSIO
69 #define PCI_VENDOR_ID_ACCESSIO 0x494f
71 #ifndef PCI_DEVICE_ID_WDG_CSM
72 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
75 /* We can only use 1 card due to the /dev/watchdog restriction */
78 static unsigned long open_lock;
79 static DEFINE_SPINLOCK(wdtpci_lock);
80 static char expect_close;
86 #define WD_TIMO 60 /* Default heartbeat = 60 seconds */
88 static int heartbeat = WD_TIMO;
89 static int wd_heartbeat;
90 module_param(heartbeat, int, 0);
91 MODULE_PARM_DESC(heartbeat,
92 "Watchdog heartbeat in seconds. (0<heartbeat<65536, default="
93 __MODULE_STRING(WD_TIMO) ")");
95 static int nowayout = WATCHDOG_NOWAYOUT;
96 module_param(nowayout, int, 0);
97 MODULE_PARM_DESC(nowayout,
98 "Watchdog cannot be stopped once started (default="
99 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
101 #ifdef CONFIG_WDT_501_PCI
102 /* Support for the Fan Tachometer on the PCI-WDT501 */
103 static int tachometer;
105 module_param(tachometer, int, 0);
106 MODULE_PARM_DESC(tachometer,
107 "PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
108 #endif /* CONFIG_WDT_501_PCI */
111 * Programming support
114 static void wdtpci_ctr_mode(int ctr, int mode)
123 static void wdtpci_ctr_load(int ctr, int val)
125 outb(val & 0xFF, WDT_COUNT0 + ctr);
127 outb(val >> 8, WDT_COUNT0 + ctr);
134 * Start the watchdog driver.
137 static int wdtpci_start(void)
141 spin_lock_irqsave(&wdtpci_lock, flags);
144 * "pet" the watchdog, as Access says.
145 * This resets the clock outputs.
147 inb(WDT_DC); /* Disable watchdog */
149 wdtpci_ctr_mode(2, 0); /* Program CTR2 for Mode 0:
150 Pulse on Terminal Count */
151 outb(0, WDT_DC); /* Enable watchdog */
153 inb(WDT_DC); /* Disable watchdog */
155 outb(0, WDT_CLOCK); /* 2.0833MHz clock */
157 inb(WDT_BUZZER); /* disable */
159 inb(WDT_OPTONOTRST); /* disable */
161 inb(WDT_OPTORST); /* disable */
163 inb(WDT_PROGOUT); /* disable */
165 wdtpci_ctr_mode(0, 3); /* Program CTR0 for Mode 3:
166 Square Wave Generator */
167 wdtpci_ctr_mode(1, 2); /* Program CTR1 for Mode 2:
169 wdtpci_ctr_mode(2, 1); /* Program CTR2 for Mode 1:
170 Retriggerable One-Shot */
171 wdtpci_ctr_load(0, 20833); /* count at 100Hz */
172 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
173 /* DO NOT LOAD CTR2 on PCI card! -- JPN */
174 outb(0, WDT_DC); /* Enable watchdog */
177 spin_unlock_irqrestore(&wdtpci_lock, flags);
184 * Stop the watchdog driver.
187 static int wdtpci_stop(void)
191 /* Turn the card off */
192 spin_lock_irqsave(&wdtpci_lock, flags);
193 inb(WDT_DC); /* Disable watchdog */
195 wdtpci_ctr_load(2, 0); /* 0 length reset pulses now */
196 spin_unlock_irqrestore(&wdtpci_lock, flags);
203 * Reload counter one with the watchdog heartbeat. We don't bother
204 * reloading the cascade counter.
207 static int wdtpci_ping(void)
211 spin_lock_irqsave(&wdtpci_lock, flags);
212 /* Write a watchdog value */
213 inb(WDT_DC); /* Disable watchdog */
215 wdtpci_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2:
217 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
218 outb(0, WDT_DC); /* Enable watchdog */
220 spin_unlock_irqrestore(&wdtpci_lock, flags);
225 * wdtpci_set_heartbeat:
226 * @t: the new heartbeat value that needs to be set.
228 * Set a new heartbeat value for the watchdog device. If the heartbeat
229 * value is incorrect we keep the old value and return -EINVAL.
230 * If successful we return 0.
232 static int wdtpci_set_heartbeat(int t)
234 /* Arbitrary, can't find the card's limits */
235 if (t < 1 || t > 65535)
239 wd_heartbeat = t * 100;
245 * @status: the new status.
247 * Extract the status information from a WDT watchdog device. There are
248 * several board variants so we have to know which bits are valid. Some
249 * bits default to one and some to zero in order to be maximally painful.
251 * we then map the bits onto the status ioctl flags.
254 static int wdtpci_get_status(int *status)
256 unsigned char new_status;
259 spin_lock_irqsave(&wdtpci_lock, flags);
260 new_status = inb(WDT_SR);
261 spin_unlock_irqrestore(&wdtpci_lock, flags);
264 if (new_status & WDC_SR_ISOI0)
265 *status |= WDIOF_EXTERN1;
266 if (new_status & WDC_SR_ISII1)
267 *status |= WDIOF_EXTERN2;
268 #ifdef CONFIG_WDT_501_PCI
269 if (!(new_status & WDC_SR_TGOOD))
270 *status |= WDIOF_OVERHEAT;
271 if (!(new_status & WDC_SR_PSUOVER))
272 *status |= WDIOF_POWEROVER;
273 if (!(new_status & WDC_SR_PSUUNDR))
274 *status |= WDIOF_POWERUNDER;
276 if (!(new_status & WDC_SR_FANGOOD))
277 *status |= WDIOF_FANFAULT;
279 #endif /* CONFIG_WDT_501_PCI */
283 #ifdef CONFIG_WDT_501_PCI
285 * wdtpci_get_temperature:
287 * Reports the temperature in degrees Fahrenheit. The API is in
288 * farenheit. It was designed by an imperial measurement luddite.
291 static int wdtpci_get_temperature(int *temperature)
295 spin_lock_irqsave(&wdtpci_lock, flags);
298 spin_unlock_irqrestore(&wdtpci_lock, flags);
299 *temperature = (c * 11 / 15) + 7;
302 #endif /* CONFIG_WDT_501_PCI */
306 * @irq: Interrupt number
307 * @dev_id: Unused as we don't allow multiple devices.
309 * Handle an interrupt from the board. These are raised when the status
310 * map changes in what the board considers an interesting way. That means
311 * a failure condition occurring.
314 static irqreturn_t wdtpci_interrupt(int irq, void *dev_id)
317 * Read the status register see what is up and
320 unsigned char status;
322 spin_lock(&wdtpci_lock);
324 status = inb(WDT_SR);
327 printk(KERN_CRIT PFX "status %d\n", status);
329 #ifdef CONFIG_WDT_501_PCI
330 if (!(status & WDC_SR_TGOOD)) {
331 u8 alarm = inb(WDT_RT);
332 printk(KERN_CRIT PFX "Overheat alarm.(%d)\n", alarm);
335 if (!(status & WDC_SR_PSUOVER))
336 printk(KERN_CRIT PFX "PSU over voltage.\n");
337 if (!(status & WDC_SR_PSUUNDR))
338 printk(KERN_CRIT PFX "PSU under voltage.\n");
340 if (!(status & WDC_SR_FANGOOD))
341 printk(KERN_CRIT PFX "Possible fan fault.\n");
343 #endif /* CONFIG_WDT_501_PCI */
344 if (!(status&WDC_SR_WCCR)) {
345 #ifdef SOFTWARE_REBOOT
347 printk(KERN_CRIT PFX "Would Reboot.\n");
349 printk(KERN_CRIT PFX "Initiating system reboot.\n");
350 emergency_restart(NULL);
353 printk(KERN_CRIT PFX "Reset in 5ms.\n");
356 spin_unlock(&wdtpci_lock);
363 * @file: file handle to the watchdog
364 * @buf: buffer to write (unused as data does not matter here
365 * @count: count of bytes
366 * @ppos: pointer to the position to write. No seeks allowed
368 * A write to a watchdog device is defined as a keepalive signal. Any
369 * write of data will do, as we we don't define content meaning.
372 static ssize_t wdtpci_write(struct file *file, const char __user *buf,
373 size_t count, loff_t *ppos)
381 for (i = 0; i != count; i++) {
383 if (get_user(c, buf+i))
396 * @file: file handle to the device
397 * @cmd: watchdog command
398 * @arg: argument pointer
400 * The watchdog API defines a common set of functions for all watchdogs
401 * according to their available features. We only actually usefully support
402 * querying capabilities and current status.
405 static long wdtpci_ioctl(struct file *file, unsigned int cmd,
410 void __user *argp = (void __user *)arg;
411 int __user *p = argp;
413 static struct watchdog_info ident = {
414 .options = WDIOF_SETTIMEOUT|
417 .firmware_version = 1,
418 .identity = "PCI-WDT500/501",
421 /* Add options according to the card we have */
422 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
423 #ifdef CONFIG_WDT_501_PCI
424 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER);
426 ident.options |= WDIOF_FANFAULT;
427 #endif /* CONFIG_WDT_501_PCI */
432 case WDIOC_GETSUPPORT:
433 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
434 case WDIOC_GETSTATUS:
435 wdtpci_get_status(&status);
436 return put_user(status, p);
437 case WDIOC_GETBOOTSTATUS:
438 return put_user(0, p);
439 case WDIOC_KEEPALIVE:
442 case WDIOC_SETTIMEOUT:
443 if (get_user(new_heartbeat, p))
445 if (wdtpci_set_heartbeat(new_heartbeat))
449 case WDIOC_GETTIMEOUT:
450 return put_user(heartbeat, p);
456 * @inode: inode of device
457 * @file: file handle to device
459 * The watchdog device has been opened. The watchdog device is single
460 * open and on opening we load the counters. Counter zero is a 100Hz
461 * cascade, into counter 1 which downcounts to reboot. When the counter
462 * triggers counter 2 downcounts the length of the reset pulse which
463 * set set to be as long as possible.
466 static int wdtpci_open(struct inode *inode, struct file *file)
468 if (test_and_set_bit(0, &open_lock))
472 __module_get(THIS_MODULE);
477 return nonseekable_open(inode, file);
482 * @inode: inode to board
483 * @file: file handle to board
485 * The watchdog has a configurable API. There is a religious dispute
486 * between people who want their watchdog to be able to shut down and
487 * those who want to be sure if the watchdog manager dies the machine
488 * reboots. In the former case we disable the counters, in the latter
489 * case you have to open it again very soon.
492 static int wdtpci_release(struct inode *inode, struct file *file)
494 if (expect_close == 42) {
497 printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
501 clear_bit(0, &open_lock);
505 #ifdef CONFIG_WDT_501_PCI
508 * @file: file handle to the watchdog board
509 * @buf: buffer to write 1 byte into
510 * @count: length of buffer
511 * @ptr: offset (no seek allowed)
513 * Read reports the temperature in degrees Fahrenheit. The API is in
514 * fahrenheit. It was designed by an imperial measurement luddite.
517 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf,
518 size_t count, loff_t *ptr)
522 if (wdtpci_get_temperature(&temperature))
525 if (copy_to_user(buf, &temperature, 1))
533 * @inode: inode of device
534 * @file: file handle to device
536 * The temperature device has been opened.
539 static int wdtpci_temp_open(struct inode *inode, struct file *file)
541 return nonseekable_open(inode, file);
545 * wdtpci_temp_release:
546 * @inode: inode to board
547 * @file: file handle to board
549 * The temperature device has been closed.
552 static int wdtpci_temp_release(struct inode *inode, struct file *file)
556 #endif /* CONFIG_WDT_501_PCI */
560 * @this: our notifier block
561 * @code: the event being reported
564 * Our notifier is called on system shutdowns. We want to turn the card
565 * off at reboot otherwise the machine will reboot again during memory
566 * test or worse yet during the following fsck. This would suck, in fact
567 * trust me - if it happens it does suck.
570 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
573 if (code == SYS_DOWN || code == SYS_HALT)
583 static const struct file_operations wdtpci_fops = {
584 .owner = THIS_MODULE,
586 .write = wdtpci_write,
587 .unlocked_ioctl = wdtpci_ioctl,
589 .release = wdtpci_release,
592 static struct miscdevice wdtpci_miscdev = {
593 .minor = WATCHDOG_MINOR,
595 .fops = &wdtpci_fops,
598 #ifdef CONFIG_WDT_501_PCI
599 static const struct file_operations wdtpci_temp_fops = {
600 .owner = THIS_MODULE,
602 .read = wdtpci_temp_read,
603 .open = wdtpci_temp_open,
604 .release = wdtpci_temp_release,
607 static struct miscdevice temp_miscdev = {
609 .name = "temperature",
610 .fops = &wdtpci_temp_fops,
612 #endif /* CONFIG_WDT_501_PCI */
615 * The WDT card needs to learn about soft shutdowns in order to
616 * turn the timebomb registers off.
619 static struct notifier_block wdtpci_notifier = {
620 .notifier_call = wdtpci_notify_sys,
624 static int __devinit wdtpci_init_one(struct pci_dev *dev,
625 const struct pci_device_id *ent)
631 printk(KERN_ERR PFX "This driver only supports one device\n");
635 if (pci_enable_device(dev)) {
636 printk(KERN_ERR PFX "Not possible to enable PCI Device\n");
640 if (pci_resource_start(dev, 2) == 0x0000) {
641 printk(KERN_ERR PFX "No I/O-Address for card detected\n");
647 io = pci_resource_start(dev, 2);
649 if (request_region(io, 16, "wdt_pci") == NULL) {
650 printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", io);
654 if (request_irq(irq, wdtpci_interrupt, IRQF_DISABLED | IRQF_SHARED,
655 "wdt_pci", &wdtpci_miscdev)) {
656 printk(KERN_ERR PFX "IRQ %d is not free\n", irq);
661 "PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%04x (Interrupt %d)\n",
664 /* Check that the heartbeat value is within its range;
665 if not reset to the default */
666 if (wdtpci_set_heartbeat(heartbeat)) {
667 wdtpci_set_heartbeat(WD_TIMO);
669 "heartbeat value must be 0 < heartbeat < 65536, using %d\n",
673 ret = register_reboot_notifier(&wdtpci_notifier);
676 "cannot register reboot notifier (err=%d)\n", ret);
680 #ifdef CONFIG_WDT_501_PCI
681 ret = misc_register(&temp_miscdev);
684 "cannot register miscdev on minor=%d (err=%d)\n",
688 #endif /* CONFIG_WDT_501_PCI */
690 ret = misc_register(&wdtpci_miscdev);
693 "cannot register miscdev on minor=%d (err=%d)\n",
694 WATCHDOG_MINOR, ret);
698 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
699 heartbeat, nowayout);
700 #ifdef CONFIG_WDT_501_PCI
701 printk(KERN_INFO "wdt: Fan Tachometer is %s\n",
702 (tachometer ? "Enabled" : "Disabled"));
703 #endif /* CONFIG_WDT_501_PCI */
710 #ifdef CONFIG_WDT_501_PCI
711 misc_deregister(&temp_miscdev);
713 #endif /* CONFIG_WDT_501_PCI */
714 unregister_reboot_notifier(&wdtpci_notifier);
716 free_irq(irq, &wdtpci_miscdev);
718 release_region(io, 16);
720 pci_disable_device(dev);
725 static void __devexit wdtpci_remove_one(struct pci_dev *pdev)
727 /* here we assume only one device will ever have
728 * been picked up and registered by probe function */
729 misc_deregister(&wdtpci_miscdev);
730 #ifdef CONFIG_WDT_501_PCI
731 misc_deregister(&temp_miscdev);
732 #endif /* CONFIG_WDT_501_PCI */
733 unregister_reboot_notifier(&wdtpci_notifier);
734 free_irq(irq, &wdtpci_miscdev);
735 release_region(io, 16);
736 pci_disable_device(pdev);
741 static struct pci_device_id wdtpci_pci_tbl[] = {
743 .vendor = PCI_VENDOR_ID_ACCESSIO,
744 .device = PCI_DEVICE_ID_WDG_CSM,
745 .subvendor = PCI_ANY_ID,
746 .subdevice = PCI_ANY_ID,
748 { 0, }, /* terminate list */
750 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
753 static struct pci_driver wdtpci_driver = {
755 .id_table = wdtpci_pci_tbl,
756 .probe = wdtpci_init_one,
757 .remove = __devexit_p(wdtpci_remove_one),
764 * Unload the watchdog. You cannot do this with any file handles open.
765 * If your watchdog is set to continue ticking on close and you unload
766 * it, well it keeps ticking. We won't get the interrupt but the board
767 * will not touch PC memory so all is fine. You just have to load a new
768 * module in xx seconds or reboot.
771 static void __exit wdtpci_cleanup(void)
773 pci_unregister_driver(&wdtpci_driver);
780 * Set up the WDT watchdog board. All we have to do is grab the
781 * resources we require and bitch if anyone beat us to them.
782 * The open() function will actually kick the board off.
785 static int __init wdtpci_init(void)
787 return pci_register_driver(&wdtpci_driver);
791 module_init(wdtpci_init);
792 module_exit(wdtpci_cleanup);
794 MODULE_AUTHOR("JP Nollmann, Alan Cox");
795 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
796 MODULE_LICENSE("GPL");
797 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
798 MODULE_ALIAS_MISCDEV(TEMP_MINOR);