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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
53 #include <linux/pci.h>
55 #include <linux/uaccess.h>
61 /* We can only use 1 card due to the /dev/watchdog restriction */
64 static unsigned long open_lock;
65 static DEFINE_SPINLOCK(wdtpci_lock);
66 static char expect_close;
68 static resource_size_t io;
72 #define WD_TIMO 60 /* Default heartbeat = 60 seconds */
74 static int heartbeat = WD_TIMO;
75 static int wd_heartbeat;
76 module_param(heartbeat, int, 0);
77 MODULE_PARM_DESC(heartbeat,
78 "Watchdog heartbeat in seconds. (0<heartbeat<65536, default="
79 __MODULE_STRING(WD_TIMO) ")");
81 static bool nowayout = WATCHDOG_NOWAYOUT;
82 module_param(nowayout, bool, 0);
83 MODULE_PARM_DESC(nowayout,
84 "Watchdog cannot be stopped once started (default="
85 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
87 /* Support for the Fan Tachometer on the PCI-WDT501 */
88 static int tachometer;
89 module_param(tachometer, int, 0);
90 MODULE_PARM_DESC(tachometer,
91 "PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
93 static int type = 500;
94 module_param(type, int, 0);
95 MODULE_PARM_DESC(type,
96 "PCI-WDT501 Card type (500 or 501 , default=500)");
102 static void wdtpci_ctr_mode(int ctr, int mode)
111 static void wdtpci_ctr_load(int ctr, int val)
113 outb(val & 0xFF, WDT_COUNT0 + ctr);
115 outb(val >> 8, WDT_COUNT0 + ctr);
122 * Start the watchdog driver.
125 static int wdtpci_start(void)
129 spin_lock_irqsave(&wdtpci_lock, flags);
132 * "pet" the watchdog, as Access says.
133 * This resets the clock outputs.
135 inb(WDT_DC); /* Disable watchdog */
137 wdtpci_ctr_mode(2, 0); /* Program CTR2 for Mode 0:
138 Pulse on Terminal Count */
139 outb(0, WDT_DC); /* Enable watchdog */
141 inb(WDT_DC); /* Disable watchdog */
143 outb(0, WDT_CLOCK); /* 2.0833MHz clock */
145 inb(WDT_BUZZER); /* disable */
147 inb(WDT_OPTONOTRST); /* disable */
149 inb(WDT_OPTORST); /* disable */
151 inb(WDT_PROGOUT); /* disable */
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:
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 */
165 spin_unlock_irqrestore(&wdtpci_lock, flags);
172 * Stop the watchdog driver.
175 static int wdtpci_stop(void)
179 /* Turn the card off */
180 spin_lock_irqsave(&wdtpci_lock, flags);
181 inb(WDT_DC); /* Disable watchdog */
183 wdtpci_ctr_load(2, 0); /* 0 length reset pulses now */
184 spin_unlock_irqrestore(&wdtpci_lock, flags);
191 * Reload counter one with the watchdog heartbeat. We don't bother
192 * reloading the cascade counter.
195 static int wdtpci_ping(void)
199 spin_lock_irqsave(&wdtpci_lock, flags);
200 /* Write a watchdog value */
201 inb(WDT_DC); /* Disable watchdog */
203 wdtpci_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2:
205 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
206 outb(0, WDT_DC); /* Enable watchdog */
208 spin_unlock_irqrestore(&wdtpci_lock, flags);
213 * wdtpci_set_heartbeat:
214 * @t: the new heartbeat value that needs to be set.
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.
220 static int wdtpci_set_heartbeat(int t)
222 /* Arbitrary, can't find the card's limits */
223 if (t < 1 || t > 65535)
227 wd_heartbeat = t * 100;
233 * @status: the new status.
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.
239 * we then map the bits onto the status ioctl flags.
242 static int wdtpci_get_status(int *status)
244 unsigned char new_status;
247 spin_lock_irqsave(&wdtpci_lock, flags);
248 new_status = inb(WDT_SR);
249 spin_unlock_irqrestore(&wdtpci_lock, flags);
252 if (new_status & WDC_SR_ISOI0)
253 *status |= WDIOF_EXTERN1;
254 if (new_status & WDC_SR_ISII1)
255 *status |= WDIOF_EXTERN2;
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;
264 if (!(new_status & WDC_SR_FANGOOD))
265 *status |= WDIOF_FANFAULT;
272 * wdtpci_get_temperature:
274 * Reports the temperature in degrees Fahrenheit. The API is in
275 * farenheit. It was designed by an imperial measurement luddite.
278 static int wdtpci_get_temperature(int *temperature)
282 spin_lock_irqsave(&wdtpci_lock, flags);
285 spin_unlock_irqrestore(&wdtpci_lock, flags);
286 *temperature = (c * 11 / 15) + 7;
292 * @irq: Interrupt number
293 * @dev_id: Unused as we don't allow multiple devices.
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.
300 static irqreturn_t wdtpci_interrupt(int irq, void *dev_id)
303 * Read the status register see what is up and
306 unsigned char status;
308 spin_lock(&wdtpci_lock);
310 status = inb(WDT_SR);
313 pr_crit("status %d\n", status);
316 if (!(status & WDC_SR_TGOOD)) {
317 pr_crit("Overheat alarm (%d)\n", inb(WDT_RT));
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");
325 if (!(status & WDC_SR_FANGOOD))
326 pr_crit("Possible fan fault\n");
329 if (!(status & WDC_SR_WCCR)) {
330 #ifdef SOFTWARE_REBOOT
332 pr_crit("Would Reboot\n");
334 pr_crit("Initiating system reboot\n");
335 emergency_restart(NULL);
338 pr_crit("Reset in 5ms\n");
341 spin_unlock(&wdtpci_lock);
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
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.
357 static ssize_t wdtpci_write(struct file *file, const char __user *buf,
358 size_t count, loff_t *ppos)
364 /* In case it was set long ago */
367 for (i = 0; i != count; i++) {
369 if (get_user(c, buf + i))
382 * @file: file handle to the device
383 * @cmd: watchdog command
384 * @arg: argument pointer
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.
391 static long wdtpci_ioctl(struct file *file, unsigned int cmd,
394 void __user *argp = (void __user *)arg;
395 int __user *p = argp;
399 struct watchdog_info ident = {
400 .options = WDIOF_SETTIMEOUT|
403 .firmware_version = 1,
404 .identity = "PCI-WDT500/501",
407 /* Add options according to the card we have */
408 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
410 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|
413 ident.options |= WDIOF_FANFAULT;
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:
427 case WDIOC_SETTIMEOUT:
428 if (get_user(new_heartbeat, p))
430 if (wdtpci_set_heartbeat(new_heartbeat))
434 case WDIOC_GETTIMEOUT:
435 return put_user(heartbeat, p);
443 * @inode: inode of device
444 * @file: file handle to device
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.
453 static int wdtpci_open(struct inode *inode, struct file *file)
455 if (test_and_set_bit(0, &open_lock))
459 __module_get(THIS_MODULE);
464 return nonseekable_open(inode, file);
469 * @inode: inode to board
470 * @file: file handle to board
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.
479 static int wdtpci_release(struct inode *inode, struct file *file)
481 if (expect_close == 42) {
484 pr_crit("Unexpected close, not stopping timer!\n");
488 clear_bit(0, &open_lock);
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)
499 * Read reports the temperature in degrees Fahrenheit. The API is in
500 * fahrenheit. It was designed by an imperial measurement luddite.
503 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf,
504 size_t count, loff_t *ptr)
508 if (wdtpci_get_temperature(&temperature))
511 if (copy_to_user(buf, &temperature, 1))
519 * @inode: inode of device
520 * @file: file handle to device
522 * The temperature device has been opened.
525 static int wdtpci_temp_open(struct inode *inode, struct file *file)
527 return nonseekable_open(inode, file);
531 * wdtpci_temp_release:
532 * @inode: inode to board
533 * @file: file handle to board
535 * The temperature device has been closed.
538 static int wdtpci_temp_release(struct inode *inode, struct file *file)
545 * @this: our notifier block
546 * @code: the event being reported
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.
555 static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
558 if (code == SYS_DOWN || code == SYS_HALT)
568 static const struct file_operations wdtpci_fops = {
569 .owner = THIS_MODULE,
571 .write = wdtpci_write,
572 .unlocked_ioctl = wdtpci_ioctl,
574 .release = wdtpci_release,
577 static struct miscdevice wdtpci_miscdev = {
578 .minor = WATCHDOG_MINOR,
580 .fops = &wdtpci_fops,
583 static const struct file_operations wdtpci_temp_fops = {
584 .owner = THIS_MODULE,
586 .read = wdtpci_temp_read,
587 .open = wdtpci_temp_open,
588 .release = wdtpci_temp_release,
591 static struct miscdevice temp_miscdev = {
593 .name = "temperature",
594 .fops = &wdtpci_temp_fops,
598 * The WDT card needs to learn about soft shutdowns in order to
599 * turn the timebomb registers off.
602 static struct notifier_block wdtpci_notifier = {
603 .notifier_call = wdtpci_notify_sys,
607 static int wdtpci_init_one(struct pci_dev *dev,
608 const struct pci_device_id *ent)
614 pr_err("This driver only supports one device\n");
618 if (type != 500 && type != 501) {
619 pr_err("unknown card type '%d'\n", type);
623 if (pci_enable_device(dev)) {
624 pr_err("Not possible to enable PCI Device\n");
628 if (pci_resource_start(dev, 2) == 0x0000) {
629 pr_err("No I/O-Address for card detected\n");
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));
641 io = pci_resource_start(dev, 2);
643 if (request_irq(irq, wdtpci_interrupt, IRQF_SHARED,
644 "wdt_pci", &wdtpci_miscdev)) {
645 pr_err("IRQ %d is not free\n", irq);
649 pr_info("PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%llx (Interrupt %d)\n",
650 (unsigned long long)io, irq);
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",
660 ret = register_reboot_notifier(&wdtpci_notifier);
662 pr_err("cannot register reboot notifier (err=%d)\n", ret);
667 ret = misc_register(&temp_miscdev);
669 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
675 ret = misc_register(&wdtpci_miscdev);
677 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
678 WATCHDOG_MINOR, ret);
682 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
683 heartbeat, nowayout);
685 pr_info("Fan Tachometer is %s\n",
686 tachometer ? "Enabled" : "Disabled");
694 misc_deregister(&temp_miscdev);
696 unregister_reboot_notifier(&wdtpci_notifier);
698 free_irq(irq, &wdtpci_miscdev);
700 pci_release_region(dev, 2);
702 pci_disable_device(dev);
707 static void wdtpci_remove_one(struct pci_dev *pdev)
709 /* here we assume only one device will ever have
710 * been picked up and registered by probe function */
711 misc_deregister(&wdtpci_miscdev);
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);
722 static const struct pci_device_id wdtpci_pci_tbl[] = {
724 .vendor = PCI_VENDOR_ID_ACCESSIO,
725 .device = PCI_DEVICE_ID_ACCESSIO_WDG_CSM,
726 .subvendor = PCI_ANY_ID,
727 .subdevice = PCI_ANY_ID,
729 { 0, }, /* terminate list */
731 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
734 static struct pci_driver wdtpci_driver = {
736 .id_table = wdtpci_pci_tbl,
737 .probe = wdtpci_init_one,
738 .remove = wdtpci_remove_one,
741 module_pci_driver(wdtpci_driver);
743 MODULE_AUTHOR("JP Nollmann, Alan Cox");
744 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
745 MODULE_LICENSE("GPL");