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[cris-mirror.git] / drivers / watchdog / wdt_pci.c
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1 /*
2 * Industrial Computer Source PCI-WDT500/501 driver
4 * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>,
5 * All Rights Reserved.
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>
18 * Release 0.10.
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
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>
56 #include <asm/system.h>
58 #define WDT_IS_PCI
59 #include "wd501p.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
71 #endif
72 #ifndef PCI_DEVICE_ID_WDG_CSM
73 #define PCI_DEVICE_ID_WDG_CSM 0x22c0
74 #endif
76 /* We can only use 1 card due to the /dev/watchdog restriction */
77 static int dev_count;
79 static unsigned long open_lock;
80 static DEFINE_SPINLOCK(wdtpci_lock);
81 static char expect_close;
83 static resource_size_t io;
84 static int irq;
86 /* Default timeout */
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 /* Support for the Fan Tachometer on the PCI-WDT501 */
103 static int tachometer;
104 module_param(tachometer, int, 0);
105 MODULE_PARM_DESC(tachometer,
106 "PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
108 static int type = 500;
109 module_param(type, int, 0);
110 MODULE_PARM_DESC(type,
111 "PCI-WDT501 Card type (500 or 501 , default=500)");
114 * Programming support
117 static void wdtpci_ctr_mode(int ctr, int mode)
119 ctr <<= 6;
120 ctr |= 0x30;
121 ctr |= (mode << 1);
122 outb(ctr, WDT_CR);
123 udelay(8);
126 static void wdtpci_ctr_load(int ctr, int val)
128 outb(val & 0xFF, WDT_COUNT0 + ctr);
129 udelay(8);
130 outb(val >> 8, WDT_COUNT0 + ctr);
131 udelay(8);
135 * wdtpci_start:
137 * Start the watchdog driver.
140 static int wdtpci_start(void)
142 unsigned long flags;
144 spin_lock_irqsave(&wdtpci_lock, flags);
147 * "pet" the watchdog, as Access says.
148 * This resets the clock outputs.
150 inb(WDT_DC); /* Disable watchdog */
151 udelay(8);
152 wdtpci_ctr_mode(2, 0); /* Program CTR2 for Mode 0:
153 Pulse on Terminal Count */
154 outb(0, WDT_DC); /* Enable watchdog */
155 udelay(8);
156 inb(WDT_DC); /* Disable watchdog */
157 udelay(8);
158 outb(0, WDT_CLOCK); /* 2.0833MHz clock */
159 udelay(8);
160 inb(WDT_BUZZER); /* disable */
161 udelay(8);
162 inb(WDT_OPTONOTRST); /* disable */
163 udelay(8);
164 inb(WDT_OPTORST); /* disable */
165 udelay(8);
166 inb(WDT_PROGOUT); /* disable */
167 udelay(8);
168 wdtpci_ctr_mode(0, 3); /* Program CTR0 for Mode 3:
169 Square Wave Generator */
170 wdtpci_ctr_mode(1, 2); /* Program CTR1 for Mode 2:
171 Rate Generator */
172 wdtpci_ctr_mode(2, 1); /* Program CTR2 for Mode 1:
173 Retriggerable One-Shot */
174 wdtpci_ctr_load(0, 20833); /* count at 100Hz */
175 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
176 /* DO NOT LOAD CTR2 on PCI card! -- JPN */
177 outb(0, WDT_DC); /* Enable watchdog */
178 udelay(8);
180 spin_unlock_irqrestore(&wdtpci_lock, flags);
181 return 0;
185 * wdtpci_stop:
187 * Stop the watchdog driver.
190 static int wdtpci_stop(void)
192 unsigned long flags;
194 /* Turn the card off */
195 spin_lock_irqsave(&wdtpci_lock, flags);
196 inb(WDT_DC); /* Disable watchdog */
197 udelay(8);
198 wdtpci_ctr_load(2, 0); /* 0 length reset pulses now */
199 spin_unlock_irqrestore(&wdtpci_lock, flags);
200 return 0;
204 * wdtpci_ping:
206 * Reload counter one with the watchdog heartbeat. We don't bother
207 * reloading the cascade counter.
210 static int wdtpci_ping(void)
212 unsigned long flags;
214 spin_lock_irqsave(&wdtpci_lock, flags);
215 /* Write a watchdog value */
216 inb(WDT_DC); /* Disable watchdog */
217 udelay(8);
218 wdtpci_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2:
219 Rate Generator */
220 wdtpci_ctr_load(1, wd_heartbeat);/* Heartbeat */
221 outb(0, WDT_DC); /* Enable watchdog */
222 udelay(8);
223 spin_unlock_irqrestore(&wdtpci_lock, flags);
224 return 0;
228 * wdtpci_set_heartbeat:
229 * @t: the new heartbeat value that needs to be set.
231 * Set a new heartbeat value for the watchdog device. If the heartbeat
232 * value is incorrect we keep the old value and return -EINVAL.
233 * If successful we return 0.
235 static int wdtpci_set_heartbeat(int t)
237 /* Arbitrary, can't find the card's limits */
238 if (t < 1 || t > 65535)
239 return -EINVAL;
241 heartbeat = t;
242 wd_heartbeat = t * 100;
243 return 0;
247 * wdtpci_get_status:
248 * @status: the new status.
250 * Extract the status information from a WDT watchdog device. There are
251 * several board variants so we have to know which bits are valid. Some
252 * bits default to one and some to zero in order to be maximally painful.
254 * we then map the bits onto the status ioctl flags.
257 static int wdtpci_get_status(int *status)
259 unsigned char new_status;
260 unsigned long flags;
262 spin_lock_irqsave(&wdtpci_lock, flags);
263 new_status = inb(WDT_SR);
264 spin_unlock_irqrestore(&wdtpci_lock, flags);
266 *status = 0;
267 if (new_status & WDC_SR_ISOI0)
268 *status |= WDIOF_EXTERN1;
269 if (new_status & WDC_SR_ISII1)
270 *status |= WDIOF_EXTERN2;
271 if (type == 501) {
272 if (!(new_status & WDC_SR_TGOOD))
273 *status |= WDIOF_OVERHEAT;
274 if (!(new_status & WDC_SR_PSUOVER))
275 *status |= WDIOF_POWEROVER;
276 if (!(new_status & WDC_SR_PSUUNDR))
277 *status |= WDIOF_POWERUNDER;
278 if (tachometer) {
279 if (!(new_status & WDC_SR_FANGOOD))
280 *status |= WDIOF_FANFAULT;
283 return 0;
287 * wdtpci_get_temperature:
289 * Reports the temperature in degrees Fahrenheit. The API is in
290 * farenheit. It was designed by an imperial measurement luddite.
293 static int wdtpci_get_temperature(int *temperature)
295 unsigned short c;
296 unsigned long flags;
297 spin_lock_irqsave(&wdtpci_lock, flags);
298 c = inb(WDT_RT);
299 udelay(8);
300 spin_unlock_irqrestore(&wdtpci_lock, flags);
301 *temperature = (c * 11 / 15) + 7;
302 return 0;
306 * wdtpci_interrupt:
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
319 * then printk it.
321 unsigned char status;
323 spin_lock(&wdtpci_lock);
325 status = inb(WDT_SR);
326 udelay(8);
328 printk(KERN_CRIT PFX "status %d\n", status);
330 if (type == 501) {
331 if (!(status & WDC_SR_TGOOD)) {
332 printk(KERN_CRIT PFX "Overheat alarm.(%d)\n",
333 inb(WDT_RT));
334 udelay(8);
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");
340 if (tachometer) {
341 if (!(status & WDC_SR_FANGOOD))
342 printk(KERN_CRIT PFX "Possible fan fault.\n");
345 if (!(status & WDC_SR_WCCR)) {
346 #ifdef SOFTWARE_REBOOT
347 #ifdef ONLY_TESTING
348 printk(KERN_CRIT PFX "Would Reboot.\n");
349 #else
350 printk(KERN_CRIT PFX "Initiating system reboot.\n");
351 emergency_restart(NULL);
352 #endif
353 #else
354 printk(KERN_CRIT PFX "Reset in 5ms.\n");
355 #endif
357 spin_unlock(&wdtpci_lock);
358 return IRQ_HANDLED;
363 * wdtpci_write:
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)
376 if (count) {
377 if (!nowayout) {
378 size_t i;
380 /* In case it was set long ago */
381 expect_close = 0;
383 for (i = 0; i != count; i++) {
384 char c;
385 if (get_user(c, buf + i))
386 return -EFAULT;
387 if (c == 'V')
388 expect_close = 42;
391 wdtpci_ping();
393 return count;
397 * wdtpci_ioctl:
398 * @file: file handle to the device
399 * @cmd: watchdog command
400 * @arg: argument pointer
402 * The watchdog API defines a common set of functions for all watchdogs
403 * according to their available features. We only actually usefully support
404 * querying capabilities and current status.
407 static long wdtpci_ioctl(struct file *file, unsigned int cmd,
408 unsigned long arg)
410 void __user *argp = (void __user *)arg;
411 int __user *p = argp;
412 int new_heartbeat;
413 int status;
415 static struct watchdog_info ident = {
416 .options = WDIOF_SETTIMEOUT|
417 WDIOF_MAGICCLOSE|
418 WDIOF_KEEPALIVEPING,
419 .firmware_version = 1,
420 .identity = "PCI-WDT500/501",
423 /* Add options according to the card we have */
424 ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
425 if (type == 501) {
426 ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|
427 WDIOF_POWEROVER);
428 if (tachometer)
429 ident.options |= WDIOF_FANFAULT;
432 switch (cmd) {
433 case WDIOC_GETSUPPORT:
434 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
435 case WDIOC_GETSTATUS:
436 wdtpci_get_status(&status);
437 return put_user(status, p);
438 case WDIOC_GETBOOTSTATUS:
439 return put_user(0, p);
440 case WDIOC_KEEPALIVE:
441 wdtpci_ping();
442 return 0;
443 case WDIOC_SETTIMEOUT:
444 if (get_user(new_heartbeat, p))
445 return -EFAULT;
446 if (wdtpci_set_heartbeat(new_heartbeat))
447 return -EINVAL;
448 wdtpci_ping();
449 /* Fall */
450 case WDIOC_GETTIMEOUT:
451 return put_user(heartbeat, p);
452 default:
453 return -ENOTTY;
458 * wdtpci_open:
459 * @inode: inode of device
460 * @file: file handle to device
462 * The watchdog device has been opened. The watchdog device is single
463 * open and on opening we load the counters. Counter zero is a 100Hz
464 * cascade, into counter 1 which downcounts to reboot. When the counter
465 * triggers counter 2 downcounts the length of the reset pulse which
466 * set set to be as long as possible.
469 static int wdtpci_open(struct inode *inode, struct file *file)
471 if (test_and_set_bit(0, &open_lock))
472 return -EBUSY;
474 if (nowayout)
475 __module_get(THIS_MODULE);
477 * Activate
479 wdtpci_start();
480 return nonseekable_open(inode, file);
484 * wdtpci_release:
485 * @inode: inode to board
486 * @file: file handle to board
488 * The watchdog has a configurable API. There is a religious dispute
489 * between people who want their watchdog to be able to shut down and
490 * those who want to be sure if the watchdog manager dies the machine
491 * reboots. In the former case we disable the counters, in the latter
492 * case you have to open it again very soon.
495 static int wdtpci_release(struct inode *inode, struct file *file)
497 if (expect_close == 42) {
498 wdtpci_stop();
499 } else {
500 printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
501 wdtpci_ping();
503 expect_close = 0;
504 clear_bit(0, &open_lock);
505 return 0;
509 * wdtpci_temp_read:
510 * @file: file handle to the watchdog board
511 * @buf: buffer to write 1 byte into
512 * @count: length of buffer
513 * @ptr: offset (no seek allowed)
515 * Read reports the temperature in degrees Fahrenheit. The API is in
516 * fahrenheit. It was designed by an imperial measurement luddite.
519 static ssize_t wdtpci_temp_read(struct file *file, char __user *buf,
520 size_t count, loff_t *ptr)
522 int temperature;
524 if (wdtpci_get_temperature(&temperature))
525 return -EFAULT;
527 if (copy_to_user(buf, &temperature, 1))
528 return -EFAULT;
530 return 1;
534 * wdtpci_temp_open:
535 * @inode: inode of device
536 * @file: file handle to device
538 * The temperature device has been opened.
541 static int wdtpci_temp_open(struct inode *inode, struct file *file)
543 return nonseekable_open(inode, file);
547 * wdtpci_temp_release:
548 * @inode: inode to board
549 * @file: file handle to board
551 * The temperature device has been closed.
554 static int wdtpci_temp_release(struct inode *inode, struct file *file)
556 return 0;
560 * notify_sys:
561 * @this: our notifier block
562 * @code: the event being reported
563 * @unused: unused
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,
572 void *unused)
574 if (code == SYS_DOWN || code == SYS_HALT)
575 wdtpci_stop();
576 return NOTIFY_DONE;
580 * Kernel Interfaces
584 static const struct file_operations wdtpci_fops = {
585 .owner = THIS_MODULE,
586 .llseek = no_llseek,
587 .write = wdtpci_write,
588 .unlocked_ioctl = wdtpci_ioctl,
589 .open = wdtpci_open,
590 .release = wdtpci_release,
593 static struct miscdevice wdtpci_miscdev = {
594 .minor = WATCHDOG_MINOR,
595 .name = "watchdog",
596 .fops = &wdtpci_fops,
599 static const struct file_operations wdtpci_temp_fops = {
600 .owner = THIS_MODULE,
601 .llseek = no_llseek,
602 .read = wdtpci_temp_read,
603 .open = wdtpci_temp_open,
604 .release = wdtpci_temp_release,
607 static struct miscdevice temp_miscdev = {
608 .minor = TEMP_MINOR,
609 .name = "temperature",
610 .fops = &wdtpci_temp_fops,
614 * The WDT card needs to learn about soft shutdowns in order to
615 * turn the timebomb registers off.
618 static struct notifier_block wdtpci_notifier = {
619 .notifier_call = wdtpci_notify_sys,
623 static int __devinit wdtpci_init_one(struct pci_dev *dev,
624 const struct pci_device_id *ent)
626 int ret = -EIO;
628 dev_count++;
629 if (dev_count > 1) {
630 printk(KERN_ERR PFX "This driver only supports one device\n");
631 return -ENODEV;
634 if (type != 500 && type != 501) {
635 printk(KERN_ERR PFX "unknown card type '%d'.\n", type);
636 return -ENODEV;
639 if (pci_enable_device(dev)) {
640 printk(KERN_ERR PFX "Not possible to enable PCI Device\n");
641 return -ENODEV;
644 if (pci_resource_start(dev, 2) == 0x0000) {
645 printk(KERN_ERR PFX "No I/O-Address for card detected\n");
646 ret = -ENODEV;
647 goto out_pci;
650 if (pci_request_region(dev, 2, "wdt_pci")) {
651 printk(KERN_ERR PFX "I/O address 0x%llx already in use\n",
652 (unsigned long long)pci_resource_start(dev, 2));
653 goto out_pci;
656 irq = dev->irq;
657 io = pci_resource_start(dev, 2);
659 if (request_irq(irq, wdtpci_interrupt, IRQF_DISABLED | IRQF_SHARED,
660 "wdt_pci", &wdtpci_miscdev)) {
661 printk(KERN_ERR PFX "IRQ %d is not free\n", irq);
662 goto out_reg;
665 printk(KERN_INFO
666 "PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%llx (Interrupt %d)\n",
667 (unsigned long long)io, irq);
669 /* Check that the heartbeat value is within its range;
670 if not reset to the default */
671 if (wdtpci_set_heartbeat(heartbeat)) {
672 wdtpci_set_heartbeat(WD_TIMO);
673 printk(KERN_INFO PFX
674 "heartbeat value must be 0 < heartbeat < 65536, using %d\n",
675 WD_TIMO);
678 ret = register_reboot_notifier(&wdtpci_notifier);
679 if (ret) {
680 printk(KERN_ERR PFX
681 "cannot register reboot notifier (err=%d)\n", ret);
682 goto out_irq;
685 if (type == 501) {
686 ret = misc_register(&temp_miscdev);
687 if (ret) {
688 printk(KERN_ERR PFX
689 "cannot register miscdev on minor=%d (err=%d)\n",
690 TEMP_MINOR, ret);
691 goto out_rbt;
695 ret = misc_register(&wdtpci_miscdev);
696 if (ret) {
697 printk(KERN_ERR PFX
698 "cannot register miscdev on minor=%d (err=%d)\n",
699 WATCHDOG_MINOR, ret);
700 goto out_misc;
703 printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
704 heartbeat, nowayout);
705 if (type == 501)
706 printk(KERN_INFO "wdt: Fan Tachometer is %s\n",
707 (tachometer ? "Enabled" : "Disabled"));
709 ret = 0;
710 out:
711 return ret;
713 out_misc:
714 if (type == 501)
715 misc_deregister(&temp_miscdev);
716 out_rbt:
717 unregister_reboot_notifier(&wdtpci_notifier);
718 out_irq:
719 free_irq(irq, &wdtpci_miscdev);
720 out_reg:
721 pci_release_region(dev, 2);
722 out_pci:
723 pci_disable_device(dev);
724 goto out;
728 static void __devexit wdtpci_remove_one(struct pci_dev *pdev)
730 /* here we assume only one device will ever have
731 * been picked up and registered by probe function */
732 misc_deregister(&wdtpci_miscdev);
733 if (type == 501)
734 misc_deregister(&temp_miscdev);
735 unregister_reboot_notifier(&wdtpci_notifier);
736 free_irq(irq, &wdtpci_miscdev);
737 pci_release_region(pdev, 2);
738 pci_disable_device(pdev);
739 dev_count--;
743 static struct pci_device_id wdtpci_pci_tbl[] = {
745 .vendor = PCI_VENDOR_ID_ACCESSIO,
746 .device = PCI_DEVICE_ID_WDG_CSM,
747 .subvendor = PCI_ANY_ID,
748 .subdevice = PCI_ANY_ID,
750 { 0, }, /* terminate list */
752 MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
755 static struct pci_driver wdtpci_driver = {
756 .name = "wdt_pci",
757 .id_table = wdtpci_pci_tbl,
758 .probe = wdtpci_init_one,
759 .remove = __devexit_p(wdtpci_remove_one),
764 * wdtpci_cleanup:
766 * Unload the watchdog. You cannot do this with any file handles open.
767 * If your watchdog is set to continue ticking on close and you unload
768 * it, well it keeps ticking. We won't get the interrupt but the board
769 * will not touch PC memory so all is fine. You just have to load a new
770 * module in xx seconds or reboot.
773 static void __exit wdtpci_cleanup(void)
775 pci_unregister_driver(&wdtpci_driver);
780 * wdtpci_init:
782 * Set up the WDT watchdog board. All we have to do is grab the
783 * resources we require and bitch if anyone beat us to them.
784 * The open() function will actually kick the board off.
787 static int __init wdtpci_init(void)
789 return pci_register_driver(&wdtpci_driver);
793 module_init(wdtpci_init);
794 module_exit(wdtpci_cleanup);
796 MODULE_AUTHOR("JP Nollmann, Alan Cox");
797 MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
798 MODULE_LICENSE("GPL");
799 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
800 MODULE_ALIAS_MISCDEV(TEMP_MINOR);