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
);