2 * Industrial Computer Source PCI-WDT500/501 driver
4 * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>,
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/delay.h>
48 #include <linux/notifier.h>
49 #include <linux/reboot.h>
50 #include <linux/init.h>
52 #include <linux/pci.h>
54 #include <linux/uaccess.h>
56 #include <asm/system.h>
61 #define PFX "wdt_pci: "
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
69 #ifndef PCI_VENDOR_ID_ACCESSIO
70 #define PCI_VENDOR_ID_ACCESSIO 0x494f
72 #ifndef PCI_DEVICE_ID_WDG_CSM
73 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
76 /* We can only use 1 card due to the /dev/watchdog restriction */
79 static unsigned long open_lock;
80 static DEFINE_SPINLOCK(wdtpci_lock);
81 static char expect_close;
87 #define WD_TIMO 60 /* Default heartbeat = 60 seconds */
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) ")");
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) ")");
102 #ifdef CONFIG_WDT_501_PCI
103 /* Support for the Fan Tachometer on the PCI-WDT501 */
104 static int tachometer;
106 module_param(tachometer, int, 0);
107 MODULE_PARM_DESC(tachometer,
108 "PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
109 #endif /* CONFIG_WDT_501_PCI */
112 * Programming support
115 static void wdtpci_ctr_mode(int ctr, int mode)
124 static void wdtpci_ctr_load(int ctr, int val)
126 outb(val & 0xFF, WDT_COUNT0 + ctr);
128 outb(val >> 8, WDT_COUNT0 + ctr);
135 * Start the watchdog driver.
138 static int wdtpci_start(void)
142 spin_lock_irqsave(&wdtpci_lock, flags);
145 * "pet" the watchdog, as Access says.
146 * This resets the clock outputs.
148 inb(WDT_DC); /* Disable watchdog */
150 wdtpci_ctr_mode(2, 0); /* Program CTR2 for Mode 0:
151 Pulse on Terminal Count */
152 outb(0, WDT_DC); /* Enable watchdog */
154 inb(WDT_DC); /* Disable watchdog */
156 outb(0, WDT_CLOCK); /* 2.0833MHz clock */
158 inb(WDT_BUZZER); /* disable */
160 inb(WDT_OPTONOTRST); /* disable */
162 inb(WDT_OPTORST); /* disable */
164 inb(WDT_PROGOUT); /* disable */
166 wdtpci_ctr_mode(0, 3); /* Program CTR0 for Mode 3:
167 Square Wave Generator */
168 wdtpci_ctr_mode(1, 2); /* Program CTR1 for Mode 2:
170 wdtpci_ctr_mode(2, 1); /* Program CTR2 for Mode 1:
171 Retriggerable One-Shot */
172 wdtpci_ctr_load(0, 20833); /* count at 100Hz */
173 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
174 /* DO NOT LOAD CTR2 on PCI card! -- JPN */
175 outb(0, WDT_DC); /* Enable watchdog */
178 spin_unlock_irqrestore(&wdtpci_lock, flags);
185 * Stop the watchdog driver.
188 static int wdtpci_stop(void)
192 /* Turn the card off */
193 spin_lock_irqsave(&wdtpci_lock, flags);
194 inb(WDT_DC); /* Disable watchdog */
196 wdtpci_ctr_load(2, 0); /* 0 length reset pulses now */
197 spin_unlock_irqrestore(&wdtpci_lock, flags);
204 * Reload counter one with the watchdog heartbeat. We don't bother
205 * reloading the cascade counter.
208 static int wdtpci_ping(void)
212 spin_lock_irqsave(&wdtpci_lock, flags);
213 /* Write a watchdog value */
214 inb(WDT_DC); /* Disable watchdog */
216 wdtpci_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2:
218 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
219 outb(0, WDT_DC); /* Enable watchdog */
221 spin_unlock_irqrestore(&wdtpci_lock, flags);
226 * wdtpci_set_heartbeat:
227 * @t: the new heartbeat value that needs to be set.
229 * Set a new heartbeat value for the watchdog device. If the heartbeat
230 * value is incorrect we keep the old value and return -EINVAL.
231 * If successful we return 0.
233 static int wdtpci_set_heartbeat(int t)
235 /* Arbitrary, can't find the card's limits */
236 if (t < 1 || t > 65535)
240 wd_heartbeat = t * 100;
246 * @status: the new status.
248 * Extract the status information from a WDT watchdog device. There are
249 * several board variants so we have to know which bits are valid. Some
250 * bits default to one and some to zero in order to be maximally painful.
252 * we then map the bits onto the status ioctl flags.
255 static int wdtpci_get_status(int *status)
257 unsigned char new_status;
260 spin_lock_irqsave(&wdtpci_lock, flags);
261 new_status = inb(WDT_SR);
262 spin_unlock_irqrestore(&wdtpci_lock, flags);
265 if (new_status & WDC_SR_ISOI0)
266 *status |= WDIOF_EXTERN1;
267 if (new_status & WDC_SR_ISII1)
268 *status |= WDIOF_EXTERN2;
269 #ifdef CONFIG_WDT_501_PCI
270 if (!(new_status & WDC_SR_TGOOD))
271 *status |= WDIOF_OVERHEAT;
272 if (!(new_status & WDC_SR_PSUOVER))
273 *status |= WDIOF_POWEROVER;
274 if (!(new_status & WDC_SR_PSUUNDR))
275 *status |= WDIOF_POWERUNDER;
277 if (!(new_status & WDC_SR_FANGOOD))
278 *status |= WDIOF_FANFAULT;
280 #endif /* CONFIG_WDT_501_PCI */
284 #ifdef CONFIG_WDT_501_PCI
286 * wdtpci_get_temperature:
288 * Reports the temperature in degrees Fahrenheit. The API is in
289 * farenheit. It was designed by an imperial measurement luddite.
292 static int wdtpci_get_temperature(int *temperature)
296 spin_lock_irqsave(&wdtpci_lock, flags);
299 spin_unlock_irqrestore(&wdtpci_lock, flags);
300 *temperature = (c * 11 / 15) + 7;
303 #endif /* CONFIG_WDT_501_PCI */
307 * @irq: Interrupt number
308 * @dev_id: Unused as we don't allow multiple devices.
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.
315 static irqreturn_t wdtpci_interrupt(int irq, void *dev_id)
318 * Read the status register see what is up and
321 unsigned char status;
323 spin_lock(&wdtpci_lock);
325 status = inb(WDT_SR);
328 printk(KERN_CRIT PFX "status %d\n", status);
330 #ifdef CONFIG_WDT_501_PCI
331 if (!(status & WDC_SR_TGOOD)) {
332 u8 alarm = inb(WDT_RT);
333 printk(KERN_CRIT PFX "Overheat alarm.(%d)\n", alarm);
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");
341 if (!(status & WDC_SR_FANGOOD))
342 printk(KERN_CRIT PFX "Possible fan fault.\n");
344 #endif /* CONFIG_WDT_501_PCI */
345 if (!(status&WDC_SR_WCCR)) {
346 #ifdef SOFTWARE_REBOOT
348 printk(KERN_CRIT PFX "Would Reboot.\n");
350 printk(KERN_CRIT PFX "Initiating system reboot.\n");
351 emergency_restart(NULL);
354 printk(KERN_CRIT PFX "Reset in 5ms.\n");
357 spin_unlock(&wdtpci_lock);
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
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.
373 static ssize_t wdtpci_write(struct file *file, const char __user *buf,
374 size_t count, loff_t *ppos)
382 for (i = 0; i != count; i++) {
384 if (get_user(c, buf + i))
397 * @file: file handle to the device
398 * @cmd: watchdog command
399 * @arg: argument pointer
401 * The watchdog API defines a common set of functions for all watchdogs
402 * according to their available features. We only actually usefully support
403 * querying capabilities and current status.
406 static long wdtpci_ioctl(struct file *file, unsigned int cmd,
411 void __user *argp = (void __user *)arg;
412 int __user *p = argp;
414 static struct watchdog_info ident = {
415 .options = WDIOF_SETTIMEOUT|
418 .firmware_version = 1,
419 .identity = "PCI-WDT500/501",
422 /* Add options according to the card we have */
423 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
424 #ifdef CONFIG_WDT_501_PCI
425 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER);
427 ident.options |= WDIOF_FANFAULT;
428 #endif /* CONFIG_WDT_501_PCI */
431 case WDIOC_GETSUPPORT:
432 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
433 case WDIOC_GETSTATUS:
434 wdtpci_get_status(&status);
435 return put_user(status, p);
436 case WDIOC_GETBOOTSTATUS:
437 return put_user(0, p);
438 case WDIOC_KEEPALIVE:
441 case WDIOC_SETTIMEOUT:
442 if (get_user(new_heartbeat, p))
444 if (wdtpci_set_heartbeat(new_heartbeat))
448 case WDIOC_GETTIMEOUT:
449 return put_user(heartbeat, p);
457 * @inode: inode of device
458 * @file: file handle to device
460 * The watchdog device has been opened. The watchdog device is single
461 * open and on opening we load the counters. Counter zero is a 100Hz
462 * cascade, into counter 1 which downcounts to reboot. When the counter
463 * triggers counter 2 downcounts the length of the reset pulse which
464 * set set to be as long as possible.
467 static int wdtpci_open(struct inode *inode, struct file *file)
469 if (test_and_set_bit(0, &open_lock))
473 __module_get(THIS_MODULE);
478 return nonseekable_open(inode, file);
483 * @inode: inode to board
484 * @file: file handle to board
486 * The watchdog has a configurable API. There is a religious dispute
487 * between people who want their watchdog to be able to shut down and
488 * those who want to be sure if the watchdog manager dies the machine
489 * reboots. In the former case we disable the counters, in the latter
490 * case you have to open it again very soon.
493 static int wdtpci_release(struct inode *inode, struct file *file)
495 if (expect_close == 42) {
498 printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
502 clear_bit(0, &open_lock);
506 #ifdef CONFIG_WDT_501_PCI
509 * @file: file handle to the watchdog board
510 * @buf: buffer to write 1 byte into
511 * @count: length of buffer
512 * @ptr: offset (no seek allowed)
514 * Read reports the temperature in degrees Fahrenheit. The API is in
515 * fahrenheit. It was designed by an imperial measurement luddite.
518 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf,
519 size_t count, loff_t *ptr)
523 if (wdtpci_get_temperature(&temperature))
526 if (copy_to_user(buf, &temperature, 1))
534 * @inode: inode of device
535 * @file: file handle to device
537 * The temperature device has been opened.
540 static int wdtpci_temp_open(struct inode *inode, struct file *file)
542 return nonseekable_open(inode, file);
546 * wdtpci_temp_release:
547 * @inode: inode to board
548 * @file: file handle to board
550 * The temperature device has been closed.
553 static int wdtpci_temp_release(struct inode *inode, struct file *file)
557 #endif /* CONFIG_WDT_501_PCI */
561 * @this: our notifier block
562 * @code: the event being reported
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.
571 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
574 if (code == SYS_DOWN || code == SYS_HALT)
584 static const struct file_operations wdtpci_fops = {
585 .owner = THIS_MODULE,
587 .write = wdtpci_write,
588 .unlocked_ioctl = wdtpci_ioctl,
590 .release = wdtpci_release,
593 static struct miscdevice wdtpci_miscdev = {
594 .minor = WATCHDOG_MINOR,
596 .fops = &wdtpci_fops,
599 #ifdef CONFIG_WDT_501_PCI
600 static const struct file_operations wdtpci_temp_fops = {
601 .owner = THIS_MODULE,
603 .read = wdtpci_temp_read,
604 .open = wdtpci_temp_open,
605 .release = wdtpci_temp_release,
608 static struct miscdevice temp_miscdev = {
610 .name = "temperature",
611 .fops = &wdtpci_temp_fops,
613 #endif /* CONFIG_WDT_501_PCI */
616 * The WDT card needs to learn about soft shutdowns in order to
617 * turn the timebomb registers off.
620 static struct notifier_block wdtpci_notifier = {
621 .notifier_call = wdtpci_notify_sys,
625 static int __devinit wdtpci_init_one(struct pci_dev *dev,
626 const struct pci_device_id *ent)
632 printk(KERN_ERR PFX "This driver only supports one device\n");
636 if (pci_enable_device(dev)) {
637 printk(KERN_ERR PFX "Not possible to enable PCI Device\n");
641 if (pci_resource_start(dev, 2) == 0x0000) {
642 printk(KERN_ERR PFX "No I/O-Address for card detected\n");
648 io = pci_resource_start(dev, 2);
650 if (request_region(io, 16, "wdt_pci") == NULL) {
651 printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", io);
655 if (request_irq(irq, wdtpci_interrupt, IRQF_DISABLED | IRQF_SHARED,
656 "wdt_pci", &wdtpci_miscdev)) {
657 printk(KERN_ERR PFX "IRQ %d is not free\n", irq);
662 "PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%04x (Interrupt %d)\n",
665 /* Check that the heartbeat value is within its range;
666 if not reset to the default */
667 if (wdtpci_set_heartbeat(heartbeat)) {
668 wdtpci_set_heartbeat(WD_TIMO);
670 "heartbeat value must be 0 < heartbeat < 65536, using %d\n",
674 ret = register_reboot_notifier(&wdtpci_notifier);
677 "cannot register reboot notifier (err=%d)\n", ret);
681 #ifdef CONFIG_WDT_501_PCI
682 ret = misc_register(&temp_miscdev);
685 "cannot register miscdev on minor=%d (err=%d)\n",
689 #endif /* CONFIG_WDT_501_PCI */
691 ret = misc_register(&wdtpci_miscdev);
694 "cannot register miscdev on minor=%d (err=%d)\n",
695 WATCHDOG_MINOR, ret);
699 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
700 heartbeat, nowayout);
701 #ifdef CONFIG_WDT_501_PCI
702 printk(KERN_INFO "wdt: Fan Tachometer is %s\n",
703 (tachometer ? "Enabled" : "Disabled"));
704 #endif /* CONFIG_WDT_501_PCI */
711 #ifdef CONFIG_WDT_501_PCI
712 misc_deregister(&temp_miscdev);
714 #endif /* CONFIG_WDT_501_PCI */
715 unregister_reboot_notifier(&wdtpci_notifier);
717 free_irq(irq, &wdtpci_miscdev);
719 release_region(io, 16);
721 pci_disable_device(dev);
726 static void __devexit wdtpci_remove_one(struct pci_dev *pdev)
728 /* here we assume only one device will ever have
729 * been picked up and registered by probe function */
730 misc_deregister(&wdtpci_miscdev);
731 #ifdef CONFIG_WDT_501_PCI
732 misc_deregister(&temp_miscdev);
733 #endif /* CONFIG_WDT_501_PCI */
734 unregister_reboot_notifier(&wdtpci_notifier);
735 free_irq(irq, &wdtpci_miscdev);
736 release_region(io, 16);
737 pci_disable_device(pdev);
742 static struct pci_device_id wdtpci_pci_tbl[] = {
744 .vendor = PCI_VENDOR_ID_ACCESSIO,
745 .device = PCI_DEVICE_ID_WDG_CSM,
746 .subvendor = PCI_ANY_ID,
747 .subdevice = PCI_ANY_ID,
749 { 0, }, /* terminate list */
751 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
754 static struct pci_driver wdtpci_driver = {
756 .id_table = wdtpci_pci_tbl,
757 .probe = wdtpci_init_one,
758 .remove = __devexit_p(wdtpci_remove_one),
765 * Unload the watchdog. You cannot do this with any file handles open.
766 * If your watchdog is set to continue ticking on close and you unload
767 * it, well it keeps ticking. We won't get the interrupt but the board
768 * will not touch PC memory so all is fine. You just have to load a new
769 * module in xx seconds or reboot.
772 static void __exit wdtpci_cleanup(void)
774 pci_unregister_driver(&wdtpci_driver);
781 * Set up the WDT watchdog board. All we have to do is grab the
782 * resources we require and bitch if anyone beat us to them.
783 * The open() function will actually kick the board off.
786 static int __init wdtpci_init(void)
788 return pci_register_driver(&wdtpci_driver);
792 module_init(wdtpci_init);
793 module_exit(wdtpci_cleanup);
795 MODULE_AUTHOR("JP Nollmann, Alan Cox");
796 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
797 MODULE_LICENSE("GPL");
798 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
799 MODULE_ALIAS_MISCDEV(TEMP_MINOR);