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 failures
33 * Joel Becker : Added WDIOC_GET/SETTIMEOUT
34 * Zwane Mwaikambo : Magic char closing, locking changes, cleanups
35 * Matt Domsch : nowayout module option
38 #include <linux/config.h>
39 #include <linux/interrupt.h>
40 #include <linux/module.h>
41 #include <linux/moduleparam.h>
42 #include <linux/types.h>
43 #include <linux/miscdevice.h>
44 #include <linux/watchdog.h>
45 #include <linux/ioport.h>
46 #include <linux/notifier.h>
47 #include <linux/reboot.h>
48 #include <linux/init.h>
50 #include <linux/pci.h>
53 #include <asm/uaccess.h>
54 #include <asm/system.h>
59 #define PFX "wdt_pci: "
62 * Until Access I/O gets their application for a PCI vendor ID approved,
63 * I don't think that it's appropriate to move these constants into the
64 * regular pci_ids.h file. -- JPN 2000/01/18
67 #ifndef PCI_VENDOR_ID_ACCESSIO
68 #define PCI_VENDOR_ID_ACCESSIO 0x494f
70 #ifndef PCI_DEVICE_ID_WDG_CSM
71 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
74 /* We can only use 1 card due to the /dev/watchdog restriction */
77 static struct semaphore open_sem;
78 static spinlock_t wdtpci_lock;
79 static char expect_close;
85 #define WD_TIMO 60 /* Default heartbeat = 60 seconds */
87 static int heartbeat = WD_TIMO;
88 static int wd_heartbeat;
89 module_param(heartbeat, int, 0);
90 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WD_TIMO) ")");
92 static int nowayout = WATCHDOG_NOWAYOUT;
93 module_param(nowayout, int, 0);
94 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
96 #ifdef CONFIG_WDT_501_PCI
97 /* Support for the Fan Tachometer on the PCI-WDT501 */
98 static int tachometer;
100 module_param(tachometer, int, 0);
101 MODULE_PARM_DESC(tachometer, "PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
102 #endif /* CONFIG_WDT_501_PCI */
105 * Programming support
108 static void wdtpci_ctr_mode(int ctr, int mode)
116 static void wdtpci_ctr_load(int ctr, int val)
118 outb_p(val&0xFF, WDT_COUNT0+ctr);
119 outb_p(val>>8, WDT_COUNT0+ctr);
125 * Start the watchdog driver.
128 static int wdtpci_start(void)
132 spin_lock_irqsave(&wdtpci_lock, flags);
135 * "pet" the watchdog, as Access says.
136 * This resets the clock outputs.
138 inb_p(WDT_DC); /* Disable watchdog */
139 wdtpci_ctr_mode(2,0); /* Program CTR2 for Mode 0: Pulse on Terminal Count */
140 outb_p(0, WDT_DC); /* Enable watchdog */
142 inb_p(WDT_DC); /* Disable watchdog */
143 outb_p(0, WDT_CLOCK); /* 2.0833MHz clock */
144 inb_p(WDT_BUZZER); /* disable */
145 inb_p(WDT_OPTONOTRST); /* disable */
146 inb_p(WDT_OPTORST); /* disable */
147 inb_p(WDT_PROGOUT); /* disable */
148 wdtpci_ctr_mode(0,3); /* Program CTR0 for Mode 3: Square Wave Generator */
149 wdtpci_ctr_mode(1,2); /* Program CTR1 for Mode 2: Rate Generator */
150 wdtpci_ctr_mode(2,1); /* Program CTR2 for Mode 1: Retriggerable One-Shot */
151 wdtpci_ctr_load(0,20833); /* count at 100Hz */
152 wdtpci_ctr_load(1,wd_heartbeat);/* Heartbeat */
153 /* DO NOT LOAD CTR2 on PCI card! -- JPN */
154 outb_p(0, WDT_DC); /* Enable watchdog */
156 spin_unlock_irqrestore(&wdtpci_lock, flags);
163 * Stop the watchdog driver.
166 static int wdtpci_stop (void)
170 /* Turn the card off */
171 spin_lock_irqsave(&wdtpci_lock, flags);
172 inb_p(WDT_DC); /* Disable watchdog */
173 wdtpci_ctr_load(2,0); /* 0 length reset pulses now */
174 spin_unlock_irqrestore(&wdtpci_lock, flags);
181 * Reload counter one with the watchdog heartbeat. We don't bother reloading
182 * the cascade counter.
185 static int wdtpci_ping(void)
189 /* Write a watchdog value */
190 spin_lock_irqsave(&wdtpci_lock, flags);
191 inb_p(WDT_DC); /* Disable watchdog */
192 wdtpci_ctr_mode(1,2); /* Re-Program CTR1 for Mode 2: Rate Generator */
193 wdtpci_ctr_load(1,wd_heartbeat);/* Heartbeat */
194 outb_p(0, WDT_DC); /* Enable watchdog */
195 spin_unlock_irqrestore(&wdtpci_lock, flags);
200 * wdtpci_set_heartbeat:
201 * @t: the new heartbeat value that needs to be set.
203 * Set a new heartbeat value for the watchdog device. If the heartbeat value is
204 * incorrect we keep the old value and return -EINVAL. If successfull we
207 static int wdtpci_set_heartbeat(int t)
209 /* Arbitrary, can't find the card's limits */
210 if ((t < 1) || (t > 65535))
214 wd_heartbeat = t * 100;
220 * @status: the new status.
222 * Extract the status information from a WDT watchdog device. There are
223 * several board variants so we have to know which bits are valid. Some
224 * bits default to one and some to zero in order to be maximally painful.
226 * we then map the bits onto the status ioctl flags.
229 static int wdtpci_get_status(int *status)
231 unsigned char new_status=inb_p(WDT_SR);
234 if (new_status & WDC_SR_ISOI0)
235 *status |= WDIOF_EXTERN1;
236 if (new_status & WDC_SR_ISII1)
237 *status |= WDIOF_EXTERN2;
238 #ifdef CONFIG_WDT_501_PCI
239 if (!(new_status & WDC_SR_TGOOD))
240 *status |= WDIOF_OVERHEAT;
241 if (!(new_status & WDC_SR_PSUOVER))
242 *status |= WDIOF_POWEROVER;
243 if (!(new_status & WDC_SR_PSUUNDR))
244 *status |= WDIOF_POWERUNDER;
246 if (!(new_status & WDC_SR_FANGOOD))
247 *status |= WDIOF_FANFAULT;
249 #endif /* CONFIG_WDT_501_PCI */
253 #ifdef CONFIG_WDT_501_PCI
255 * wdtpci_get_temperature:
257 * Reports the temperature in degrees Fahrenheit. The API is in
258 * farenheit. It was designed by an imperial measurement luddite.
261 static int wdtpci_get_temperature(int *temperature)
263 unsigned short c=inb_p(WDT_RT);
265 *temperature = (c * 11 / 15) + 7;
268 #endif /* CONFIG_WDT_501_PCI */
272 * @irq: Interrupt number
273 * @dev_id: Unused as we don't allow multiple devices.
276 * Handle an interrupt from the board. These are raised when the status
277 * map changes in what the board considers an interesting way. That means
278 * a failure condition occurring.
281 static irqreturn_t wdtpci_interrupt(int irq, void *dev_id, struct pt_regs *regs)
284 * Read the status register see what is up and
287 unsigned char status=inb_p(WDT_SR);
289 printk(KERN_CRIT PFX "status %d\n", status);
291 #ifdef CONFIG_WDT_501_PCI
292 if (!(status & WDC_SR_TGOOD))
293 printk(KERN_CRIT PFX "Overheat alarm.(%d)\n",inb_p(WDT_RT));
294 if (!(status & WDC_SR_PSUOVER))
295 printk(KERN_CRIT PFX "PSU over voltage.\n");
296 if (!(status & WDC_SR_PSUUNDR))
297 printk(KERN_CRIT PFX "PSU under voltage.\n");
299 if (!(status & WDC_SR_FANGOOD))
300 printk(KERN_CRIT PFX "Possible fan fault.\n");
302 #endif /* CONFIG_WDT_501_PCI */
303 if (!(status&WDC_SR_WCCR))
304 #ifdef SOFTWARE_REBOOT
306 printk(KERN_CRIT PFX "Would Reboot.\n");
308 printk(KERN_CRIT PFX "Initiating system reboot.\n");
309 emergency_restart(NULL);
312 printk(KERN_CRIT PFX "Reset in 5ms.\n");
320 * @file: file handle to the watchdog
321 * @buf: buffer to write (unused as data does not matter here
322 * @count: count of bytes
323 * @ppos: pointer to the position to write. No seeks allowed
325 * A write to a watchdog device is defined as a keepalive signal. Any
326 * write of data will do, as we we don't define content meaning.
329 static ssize_t wdtpci_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
337 for (i = 0; i != count; i++) {
339 if(get_user(c, buf+i))
353 * @inode: inode of the device
354 * @file: file handle to the device
355 * @cmd: watchdog command
356 * @arg: argument pointer
358 * The watchdog API defines a common set of functions for all watchdogs
359 * according to their available features. We only actually usefully support
360 * querying capabilities and current status.
363 static int wdtpci_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
368 void __user *argp = (void __user *)arg;
369 int __user *p = argp;
371 static struct watchdog_info ident = {
372 .options = WDIOF_SETTIMEOUT|
375 .firmware_version = 1,
376 .identity = "PCI-WDT500/501",
379 /* Add options according to the card we have */
380 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
381 #ifdef CONFIG_WDT_501_PCI
382 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER);
384 ident.options |= WDIOF_FANFAULT;
385 #endif /* CONFIG_WDT_501_PCI */
391 case WDIOC_GETSUPPORT:
392 return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;
394 case WDIOC_GETSTATUS:
395 wdtpci_get_status(&status);
396 return put_user(status, p);
397 case WDIOC_GETBOOTSTATUS:
398 return put_user(0, p);
399 case WDIOC_KEEPALIVE:
402 case WDIOC_SETTIMEOUT:
403 if (get_user(new_heartbeat, p))
406 if (wdtpci_set_heartbeat(new_heartbeat))
411 case WDIOC_GETTIMEOUT:
412 return put_user(heartbeat, p);
418 * @inode: inode of device
419 * @file: file handle to device
421 * The watchdog device has been opened. The watchdog device is single
422 * open and on opening we load the counters. Counter zero is a 100Hz
423 * cascade, into counter 1 which downcounts to reboot. When the counter
424 * triggers counter 2 downcounts the length of the reset pulse which
425 * set set to be as long as possible.
428 static int wdtpci_open(struct inode *inode, struct file *file)
430 if (down_trylock(&open_sem))
434 __module_get(THIS_MODULE);
440 return nonseekable_open(inode, file);
445 * @inode: inode to board
446 * @file: file handle to board
448 * The watchdog has a configurable API. There is a religious dispute
449 * between people who want their watchdog to be able to shut down and
450 * those who want to be sure if the watchdog manager dies the machine
451 * reboots. In the former case we disable the counters, in the latter
452 * case you have to open it again very soon.
455 static int wdtpci_release(struct inode *inode, struct file *file)
457 if (expect_close == 42) {
460 printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
468 #ifdef CONFIG_WDT_501_PCI
471 * @file: file handle to the watchdog board
472 * @buf: buffer to write 1 byte into
473 * @count: length of buffer
474 * @ptr: offset (no seek allowed)
476 * Read reports the temperature in degrees Fahrenheit. The API is in
477 * fahrenheit. It was designed by an imperial measurement luddite.
480 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf, size_t count, loff_t *ptr)
484 if (wdtpci_get_temperature(&temperature))
487 if (copy_to_user (buf, &temperature, 1))
495 * @inode: inode of device
496 * @file: file handle to device
498 * The temperature device has been opened.
501 static int wdtpci_temp_open(struct inode *inode, struct file *file)
503 return nonseekable_open(inode, file);
507 * wdtpci_temp_release:
508 * @inode: inode to board
509 * @file: file handle to board
511 * The temperature device has been closed.
514 static int wdtpci_temp_release(struct inode *inode, struct file *file)
518 #endif /* CONFIG_WDT_501_PCI */
522 * @this: our notifier block
523 * @code: the event being reported
526 * Our notifier is called on system shutdowns. We want to turn the card
527 * off at reboot otherwise the machine will reboot again during memory
528 * test or worse yet during the following fsck. This would suck, in fact
529 * trust me - if it happens it does suck.
532 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
535 if (code==SYS_DOWN || code==SYS_HALT) {
536 /* Turn the card off */
547 static struct file_operations wdtpci_fops = {
548 .owner = THIS_MODULE,
550 .write = wdtpci_write,
551 .ioctl = wdtpci_ioctl,
553 .release = wdtpci_release,
556 static struct miscdevice wdtpci_miscdev = {
557 .minor = WATCHDOG_MINOR,
559 .fops = &wdtpci_fops,
562 #ifdef CONFIG_WDT_501_PCI
563 static struct file_operations wdtpci_temp_fops = {
564 .owner = THIS_MODULE,
566 .read = wdtpci_temp_read,
567 .open = wdtpci_temp_open,
568 .release = wdtpci_temp_release,
571 static struct miscdevice temp_miscdev = {
573 .name = "temperature",
574 .fops = &wdtpci_temp_fops,
576 #endif /* CONFIG_WDT_501_PCI */
579 * The WDT card needs to learn about soft shutdowns in order to
580 * turn the timebomb registers off.
583 static struct notifier_block wdtpci_notifier = {
584 .notifier_call = wdtpci_notify_sys,
588 static int __devinit wdtpci_init_one (struct pci_dev *dev,
589 const struct pci_device_id *ent)
595 printk (KERN_ERR PFX "this driver only supports 1 device\n");
599 if (pci_enable_device (dev)) {
600 printk (KERN_ERR PFX "Not possible to enable PCI Device\n");
604 if (pci_resource_start (dev, 2) == 0x0000) {
605 printk (KERN_ERR PFX "No I/O-Address for card detected\n");
610 sema_init(&open_sem, 1);
611 spin_lock_init(&wdtpci_lock);
614 io = pci_resource_start (dev, 2);
616 if (request_region (io, 16, "wdt_pci") == NULL) {
617 printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", io);
621 if (request_irq (irq, wdtpci_interrupt, SA_INTERRUPT | SA_SHIRQ,
622 "wdt_pci", &wdtpci_miscdev)) {
623 printk (KERN_ERR PFX "IRQ %d is not free\n", irq);
627 printk ("PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%04x (Interrupt %d)\n",
630 /* Check that the heartbeat value is within it's range ; if not reset to the default */
631 if (wdtpci_set_heartbeat(heartbeat)) {
632 wdtpci_set_heartbeat(WD_TIMO);
633 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
637 ret = register_reboot_notifier (&wdtpci_notifier);
639 printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", ret);
643 #ifdef CONFIG_WDT_501_PCI
644 ret = misc_register (&temp_miscdev);
646 printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
650 #endif /* CONFIG_WDT_501_PCI */
652 ret = misc_register (&wdtpci_miscdev);
654 printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
655 WATCHDOG_MINOR, ret);
659 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
660 heartbeat, nowayout);
661 #ifdef CONFIG_WDT_501_PCI
662 printk(KERN_INFO "wdt: Fan Tachometer is %s\n", (tachometer ? "Enabled" : "Disabled"));
663 #endif /* CONFIG_WDT_501_PCI */
670 #ifdef CONFIG_WDT_501_PCI
671 misc_deregister(&temp_miscdev);
673 #endif /* CONFIG_WDT_501_PCI */
674 unregister_reboot_notifier(&wdtpci_notifier);
676 free_irq(irq, &wdtpci_miscdev);
678 release_region (io, 16);
680 pci_disable_device(dev);
685 static void __devexit wdtpci_remove_one (struct pci_dev *pdev)
687 /* here we assume only one device will ever have
688 * been picked up and registered by probe function */
689 misc_deregister(&wdtpci_miscdev);
690 #ifdef CONFIG_WDT_501_PCI
691 misc_deregister(&temp_miscdev);
692 #endif /* CONFIG_WDT_501_PCI */
693 unregister_reboot_notifier(&wdtpci_notifier);
694 free_irq(irq, &wdtpci_miscdev);
695 release_region(io, 16);
696 pci_disable_device(pdev);
701 static struct pci_device_id wdtpci_pci_tbl[] = {
703 .vendor = PCI_VENDOR_ID_ACCESSIO,
704 .device = PCI_DEVICE_ID_WDG_CSM,
705 .subvendor = PCI_ANY_ID,
706 .subdevice = PCI_ANY_ID,
708 { 0, }, /* terminate list */
710 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
713 static struct pci_driver wdtpci_driver = {
714 .owner = THIS_MODULE,
716 .id_table = wdtpci_pci_tbl,
717 .probe = wdtpci_init_one,
718 .remove = __devexit_p(wdtpci_remove_one),
725 * Unload the watchdog. You cannot do this with any file handles open.
726 * If your watchdog is set to continue ticking on close and you unload
727 * it, well it keeps ticking. We won't get the interrupt but the board
728 * will not touch PC memory so all is fine. You just have to load a new
729 * module in xx seconds or reboot.
732 static void __exit wdtpci_cleanup(void)
734 pci_unregister_driver (&wdtpci_driver);
741 * Set up the WDT watchdog board. All we have to do is grab the
742 * resources we require and bitch if anyone beat us to them.
743 * The open() function will actually kick the board off.
746 static int __init wdtpci_init(void)
748 return pci_register_driver (&wdtpci_driver);
752 module_init(wdtpci_init);
753 module_exit(wdtpci_cleanup);
755 MODULE_AUTHOR("JP Nollmann, Alan Cox");
756 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
757 MODULE_LICENSE("GPL");
758 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
759 MODULE_ALIAS_MISCDEV(TEMP_MINOR);