/*
* Industrial Computer Source PCI-WDT500/501 driver
*
* (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved.
* http://www.redhat.com
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
* warranty for any of this software. This material is provided
* "AS-IS" and at no charge.
*
* (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
*
* Release 0.10.
*
* Fixes
* Dave Gregorich : Modularisation and minor bugs
* Alan Cox : Added the watchdog ioctl() stuff
* Alan Cox : Fixed the reboot problem (as noted by
* Matt Crocker).
* Alan Cox : Added wdt= boot option
* Alan Cox : Cleaned up copy/user stuff
* Tim Hockin : Added insmod parameters, comment cleanup
* Parameterized timeout
* JP Nollmann : Added support for PCI wdt501p
* Alan Cox : Split ISA and PCI cards into two drivers
* Jeff Garzik : PCI cleanups
* Tigran Aivazian : Restructured wdtpci_init_one() to handle failures
* Joel Becker : Added WDIOC_GET/SETTIMEOUT
* Zwane Mwaikambo : Magic char closing, locking changes, cleanups
* Matt Domsch : nowayout module option
*/
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/ioport.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/pci.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <asm/system.h>
#define WDT_IS_PCI
#include "wd501p.h"
#define PFX "wdt_pci: "
/*
* Until Access I/O gets their application for a PCI vendor ID approved,
* I don't think that it's appropriate to move these constants into the
* regular pci_ids.h file. -- JPN 2000/01/18
*/
#ifndef PCI_VENDOR_ID_ACCESSIO
#define PCI_VENDOR_ID_ACCESSIO 0x494f
#endif
#ifndef PCI_DEVICE_ID_WDG_CSM
#define PCI_DEVICE_ID_WDG_CSM 0x22c0
#endif
/* We can only use 1 card due to the /dev/watchdog restriction */
static int dev_count;
static struct semaphore open_sem;
static spinlock_t wdtpci_lock;
static char expect_close;
static int io;
static int irq;
/* Default timeout */
#define WD_TIMO 60 /* Default heartbeat = 60 seconds */
static int heartbeat = WD_TIMO;
static int wd_heartbeat;
module_param(heartbeat, int, 0);
MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536, default=" __MODULE_STRING(WD_TIMO) ")");
static int nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, int, 0);
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
#ifdef CONFIG_WDT_501_PCI
/* Support for the Fan Tachometer on the PCI-WDT501 */
static int tachometer;
module_param(tachometer, int, 0);
MODULE_PARM_DESC(tachometer, "PCI-WDT501 Fan Tachometer support (0=disable, default=0)");
#endif /* CONFIG_WDT_501_PCI */
/*
* Programming support
*/
static void wdtpci_ctr_mode(int ctr, int mode)
{
ctr<<=6;
ctr|=0x30;
ctr|=(mode<<1);
outb_p(ctr, WDT_CR);
}
static void wdtpci_ctr_load(int ctr, int val)
{
outb_p(val&0xFF, WDT_COUNT0+ctr);
outb_p(val>>8, WDT_COUNT0+ctr);
}
/**
* wdtpci_start:
*
* Start the watchdog driver.
*/
static int wdtpci_start(void)
{
unsigned long flags;
spin_lock_irqsave(&wdtpci_lock, flags);
/*
* "pet" the watchdog, as Access says.
* This resets the clock outputs.
*/
inb_p(WDT_DC); /* Disable watchdog */
wdtpci_ctr_mode(2,0); /* Program CTR2 for Mode 0: Pulse on Terminal Count */
outb_p(0, WDT_DC); /* Enable watchdog */
inb_p(WDT_DC); /* Disable watchdog */
outb_p(0, WDT_CLOCK); /* 2.0833MHz clock */
inb_p(WDT_BUZZER); /* disable */
inb_p(WDT_OPTONOTRST); /* disable */
inb_p(WDT_OPTORST); /* disable */
inb_p(WDT_PROGOUT); /* disable */
wdtpci_ctr_mode(0,3); /* Program CTR0 for Mode 3: Square Wave Generator */
wdtpci_ctr_mode(1,2); /* Program CTR1 for Mode 2: Rate Generator */
wdtpci_ctr_mode(2,1); /* Program CTR2 for Mode 1: Retriggerable One-Shot */
wdtpci_ctr_load(0,20833); /* count at 100Hz */
wdtpci_ctr_load(1,wd_heartbeat);/* Heartbeat */
/* DO NOT LOAD CTR2 on PCI card! -- JPN */
outb_p(0, WDT_DC); /* Enable watchdog */
spin_unlock_irqrestore(&wdtpci_lock, flags);
return 0;
}
/**
* wdtpci_stop:
*
* Stop the watchdog driver.
*/
static int wdtpci_stop (void)
{
unsigned long flags;
/* Turn the card off */
spin_lock_irqsave(&wdtpci_lock, flags);
inb_p(WDT_DC); /* Disable watchdog */
wdtpci_ctr_load(2,0); /* 0 length reset pulses now */
spin_unlock_irqrestore(&wdtpci_lock, flags);
return 0;
}
/**
* wdtpci_ping:
*
* Reload counter one with the watchdog heartbeat. We don't bother reloading
* the cascade counter.
*/
static int wdtpci_ping(void)
{
unsigned long flags;
/* Write a watchdog value */
spin_lock_irqsave(&wdtpci_lock, flags);
inb_p(WDT_DC); /* Disable watchdog */
wdtpci_ctr_mode(1,2); /* Re-Program CTR1 for Mode 2: Rate Generator */
wdtpci_ctr_load(1,wd_heartbeat);/* Heartbeat */
outb_p(0, WDT_DC); /* Enable watchdog */
spin_unlock_irqrestore(&wdtpci_lock, flags);
return 0;
}
/**
* wdtpci_set_heartbeat:
* @t: the new heartbeat value that needs to be set.
*
* Set a new heartbeat value for the watchdog device. If the heartbeat value is
* incorrect we keep the old value and return -EINVAL. If successfull we
* return 0.
*/
static int wdtpci_set_heartbeat(int t)
{
/* Arbitrary, can't find the card's limits */
if ((t < 1) || (t > 65535))
return -EINVAL;
heartbeat = t;
wd_heartbeat = t * 100;
return 0;
}
/**
* wdtpci_get_status:
* @status: the new status.
*
* Extract the status information from a WDT watchdog device. There are
* several board variants so we have to know which bits are valid. Some
* bits default to one and some to zero in order to be maximally painful.
*
* we then map the bits onto the status ioctl flags.
*/
static int wdtpci_get_status(int *status)
{
unsigned char new_status=inb_p(WDT_SR);
*status=0;
if (new_status & WDC_SR_ISOI0)
*status |= WDIOF_EXTERN1;
if (new_status & WDC_SR_ISII1)
*status |= WDIOF_EXTERN2;
#ifdef CONFIG_WDT_501_PCI
if (!(new_status & WDC_SR_TGOOD))
*status |= WDIOF_OVERHEAT;
if (!(new_status & WDC_SR_PSUOVER))
*status |= WDIOF_POWEROVER;
if (!(new_status & WDC_SR_PSUUNDR))
*status |= WDIOF_POWERUNDER;
if (tachometer) {
if (!(new_status & WDC_SR_FANGOOD))
*status |= WDIOF_FANFAULT;
}
#endif /* CONFIG_WDT_501_PCI */
return 0;
}
#ifdef CONFIG_WDT_501_PCI
/**
* wdtpci_get_temperature:
*
* Reports the temperature in degrees Fahrenheit. The API is in
* farenheit. It was designed by an imperial measurement luddite.
*/
static int wdtpci_get_temperature(int *temperature)
{
unsigned short c=inb_p(WDT_RT);
*temperature = (c * 11 / 15) + 7;
return 0;
}
#endif /* CONFIG_WDT_501_PCI */
/**
* wdtpci_interrupt:
* @irq: Interrupt number
* @dev_id: Unused as we don't allow multiple devices.
* @regs: Unused.
*
* Handle an interrupt from the board. These are raised when the status
* map changes in what the board considers an interesting way. That means
* a failure condition occurring.
*/
static irqreturn_t wdtpci_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
/*
* Read the status register see what is up and
* then printk it.
*/
unsigned char status=inb_p(WDT_SR);
printk(KERN_CRIT PFX "status %d\n", status);
#ifdef CONFIG_WDT_501_PCI
if (!(status & WDC_SR_TGOOD))
printk(KERN_CRIT PFX "Overheat alarm.(%d)\n",inb_p(WDT_RT));
if (!(status & WDC_SR_PSUOVER))
printk(KERN_CRIT PFX "PSU over voltage.\n");
if (!(status & WDC_SR_PSUUNDR))
printk(KERN_CRIT PFX "PSU under voltage.\n");
if (tachometer) {
if (!(status & WDC_SR_FANGOOD))
printk(KERN_CRIT PFX "Possible fan fault.\n");
}
#endif /* CONFIG_WDT_501_PCI */
if (!(status&WDC_SR_WCCR))
#ifdef SOFTWARE_REBOOT
#ifdef ONLY_TESTING
printk(KERN_CRIT PFX "Would Reboot.\n");
#else
printk(KERN_CRIT PFX "Initiating system reboot.\n");
emergency_restart(NULL);
#endif
#else
printk(KERN_CRIT PFX "Reset in 5ms.\n");
#endif
return IRQ_HANDLED;
}
/**
* wdtpci_write:
* @file: file handle to the watchdog
* @buf: buffer to write (unused as data does not matter here
* @count: count of bytes
* @ppos: pointer to the position to write. No seeks allowed
*
* A write to a watchdog device is defined as a keepalive signal. Any
* write of data will do, as we we don't define content meaning.
*/
static ssize_t wdtpci_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
{
if (count) {
if (!nowayout) {
size_t i;
expect_close = 0;
for (i = 0; i != count; i++) {
char c;
if(get_user(c, buf+i))
return -EFAULT;
if (c == 'V')
expect_close = 42;
}
}
wdtpci_ping();
}
return count;
}
/**
* wdtpci_ioctl:
* @inode: inode of the device
* @file: file handle to the device
* @cmd: watchdog command
* @arg: argument pointer
*
* The watchdog API defines a common set of functions for all watchdogs
* according to their available features. We only actually usefully support
* querying capabilities and current status.
*/
static int wdtpci_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
unsigned long arg)
{
int new_heartbeat;
int status;
void __user *argp = (void __user *)arg;
int __user *p = argp;
static struct watchdog_info ident = {
.options = WDIOF_SETTIMEOUT|
WDIOF_MAGICCLOSE|
WDIOF_KEEPALIVEPING,
.firmware_version = 1,
.identity = "PCI-WDT500/501",
};
/* Add options according to the card we have */
ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2);
#ifdef CONFIG_WDT_501_PCI
ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER);
if (tachometer)
ident.options |= WDIOF_FANFAULT;
#endif /* CONFIG_WDT_501_PCI */
switch(cmd)
{
default:
return -ENOIOCTLCMD;
case WDIOC_GETSUPPORT:
return copy_to_user(argp, &ident, sizeof(ident))?-EFAULT:0;
case WDIOC_GETSTATUS:
wdtpci_get_status(&status);
return put_user(status, p);
case WDIOC_GETBOOTSTATUS:
return put_user(0, p);
case WDIOC_KEEPALIVE:
wdtpci_ping();
return 0;
case WDIOC_SETTIMEOUT:
if (get_user(new_heartbeat, p))
return -EFAULT;
if (wdtpci_set_heartbeat(new_heartbeat))
return -EINVAL;
wdtpci_ping();
/* Fall */
case WDIOC_GETTIMEOUT:
return put_user(heartbeat, p);
}
}
/**
* wdtpci_open:
* @inode: inode of device
* @file: file handle to device
*
* The watchdog device has been opened. The watchdog device is single
* open and on opening we load the counters. Counter zero is a 100Hz
* cascade, into counter 1 which downcounts to reboot. When the counter
* triggers counter 2 downcounts the length of the reset pulse which
* set set to be as long as possible.
*/
static int wdtpci_open(struct inode *inode, struct file *file)
{
if (down_trylock(&open_sem))
return -EBUSY;
if (nowayout) {
__module_get(THIS_MODULE);
}
/*
* Activate
*/
wdtpci_start();
return nonseekable_open(inode, file);
}
/**
* wdtpci_release:
* @inode: inode to board
* @file: file handle to board
*
* The watchdog has a configurable API. There is a religious dispute
* between people who want their watchdog to be able to shut down and
* those who want to be sure if the watchdog manager dies the machine
* reboots. In the former case we disable the counters, in the latter
* case you have to open it again very soon.
*/
static int wdtpci_release(struct inode *inode, struct file *file)
{
if (expect_close == 42) {
wdtpci_stop();
} else {
printk(KERN_CRIT PFX "Unexpected close, not stopping timer!");
wdtpci_ping();
}
expect_close = 0;
up(&open_sem);
return 0;
}
#ifdef CONFIG_WDT_501_PCI
/**
* wdtpci_temp_read:
* @file: file handle to the watchdog board
* @buf: buffer to write 1 byte into
* @count: length of buffer
* @ptr: offset (no seek allowed)
*
* Read reports the temperature in degrees Fahrenheit. The API is in
* fahrenheit. It was designed by an imperial measurement luddite.
*/
static ssize_t wdtpci_temp_read(struct file *file, char __user *buf, size_t count, loff_t *ptr)
{
int temperature;
if (wdtpci_get_temperature(&temperature))
return -EFAULT;
if (copy_to_user (buf, &temperature, 1))
return -EFAULT;
return 1;
}
/**
* wdtpci_temp_open:
* @inode: inode of device
* @file: file handle to device
*
* The temperature device has been opened.
*/
static int wdtpci_temp_open(struct inode *inode, struct file *file)
{
return nonseekable_open(inode, file);
}
/**
* wdtpci_temp_release:
* @inode: inode to board
* @file: file handle to board
*
* The temperature device has been closed.
*/
static int wdtpci_temp_release(struct inode *inode, struct file *file)
{
return 0;
}
#endif /* CONFIG_WDT_501_PCI */
/**
* notify_sys:
* @this: our notifier block
* @code: the event being reported
* @unused: unused
*
* Our notifier is called on system shutdowns. We want to turn the card
* off at reboot otherwise the machine will reboot again during memory
* test or worse yet during the following fsck. This would suck, in fact
* trust me - if it happens it does suck.
*/
static int wdtpci_notify_sys(struct notifier_block *this, unsigned long code,
void *unused)
{
if (code==SYS_DOWN || code==SYS_HALT) {
/* Turn the card off */
wdtpci_stop();
}
return NOTIFY_DONE;
}
/*
* Kernel Interfaces
*/
static const struct file_operations wdtpci_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = wdtpci_write,
.ioctl = wdtpci_ioctl,
.open = wdtpci_open,
.release = wdtpci_release,
};
static struct miscdevice wdtpci_miscdev = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &wdtpci_fops,
};
#ifdef CONFIG_WDT_501_PCI
static const struct file_operations wdtpci_temp_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = wdtpci_temp_read,
.open = wdtpci_temp_open,
.release = wdtpci_temp_release,
};
static struct miscdevice temp_miscdev = {
.minor = TEMP_MINOR,
.name = "temperature",
.fops = &wdtpci_temp_fops,
};
#endif /* CONFIG_WDT_501_PCI */
/*
* The WDT card needs to learn about soft shutdowns in order to
* turn the timebomb registers off.
*/
static struct notifier_block wdtpci_notifier = {
.notifier_call = wdtpci_notify_sys,
};
static int __devinit wdtpci_init_one (struct pci_dev *dev,
const struct pci_device_id *ent)
{
int ret = -EIO;
dev_count++;
if (dev_count > 1) {
printk (KERN_ERR PFX "this driver only supports 1 device\n");
return -ENODEV;
}
if (pci_enable_device (dev)) {
printk (KERN_ERR PFX "Not possible to enable PCI Device\n");
return -ENODEV;
}
if (pci_resource_start (dev, 2) == 0x0000) {
printk (KERN_ERR PFX "No I/O-Address for card detected\n");
ret = -ENODEV;
goto out_pci;
}
sema_init(&open_sem, 1);
spin_lock_init(&wdtpci_lock);
irq = dev->irq;
io = pci_resource_start (dev, 2);
if (request_region (io, 16, "wdt_pci") == NULL) {
printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", io);
goto out_pci;
}
if (request_irq (irq, wdtpci_interrupt, IRQF_DISABLED | IRQF_SHARED,
"wdt_pci", &wdtpci_miscdev)) {
printk (KERN_ERR PFX "IRQ %d is not free\n", irq);
goto out_reg;
}
printk ("PCI-WDT500/501 (PCI-WDG-CSM) driver 0.10 at 0x%04x (Interrupt %d)\n",
io, irq);
/* Check that the heartbeat value is within it's range ; if not reset to the default */
if (wdtpci_set_heartbeat(heartbeat)) {
wdtpci_set_heartbeat(WD_TIMO);
printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
WD_TIMO);
}
ret = register_reboot_notifier (&wdtpci_notifier);
if (ret) {
printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", ret);
goto out_irq;
}
#ifdef CONFIG_WDT_501_PCI
ret = misc_register (&temp_miscdev);
if (ret) {
printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
TEMP_MINOR, ret);
goto out_rbt;
}
#endif /* CONFIG_WDT_501_PCI */
ret = misc_register (&wdtpci_miscdev);
if (ret) {
printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
WATCHDOG_MINOR, ret);
goto out_misc;
}
printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
heartbeat, nowayout);
#ifdef CONFIG_WDT_501_PCI
printk(KERN_INFO "wdt: Fan Tachometer is %s\n", (tachometer ? "Enabled" : "Disabled"));
#endif /* CONFIG_WDT_501_PCI */
ret = 0;
out:
return ret;
out_misc:
#ifdef CONFIG_WDT_501_PCI
misc_deregister(&temp_miscdev);
out_rbt:
#endif /* CONFIG_WDT_501_PCI */
unregister_reboot_notifier(&wdtpci_notifier);
out_irq:
free_irq(irq, &wdtpci_miscdev);
out_reg:
release_region (io, 16);
out_pci:
pci_disable_device(dev);
goto out;
}
static void __devexit wdtpci_remove_one (struct pci_dev *pdev)
{
/* here we assume only one device will ever have
* been picked up and registered by probe function */
misc_deregister(&wdtpci_miscdev);
#ifdef CONFIG_WDT_501_PCI
misc_deregister(&temp_miscdev);
#endif /* CONFIG_WDT_501_PCI */
unregister_reboot_notifier(&wdtpci_notifier);
free_irq(irq, &wdtpci_miscdev);
release_region(io, 16);
pci_disable_device(pdev);
dev_count--;
}
static struct pci_device_id wdtpci_pci_tbl[] = {
{
.vendor = PCI_VENDOR_ID_ACCESSIO,
.device = PCI_DEVICE_ID_WDG_CSM,
.subvendor = PCI_ANY_ID,
.subdevice = PCI_ANY_ID,
},
{ 0, }, /* terminate list */
};
MODULE_DEVICE_TABLE(pci, wdtpci_pci_tbl);
static struct pci_driver wdtpci_driver = {
.name = "wdt_pci",
.id_table = wdtpci_pci_tbl,
.probe = wdtpci_init_one,
.remove = __devexit_p(wdtpci_remove_one),
};
/**
* wdtpci_cleanup:
*
* Unload the watchdog. You cannot do this with any file handles open.
* If your watchdog is set to continue ticking on close and you unload
* it, well it keeps ticking. We won't get the interrupt but the board
* will not touch PC memory so all is fine. You just have to load a new
* module in xx seconds or reboot.
*/
static void __exit wdtpci_cleanup(void)
{
pci_unregister_driver (&wdtpci_driver);
}
/**
* wdtpci_init:
*
* Set up the WDT watchdog board. All we have to do is grab the
* resources we require and bitch if anyone beat us to them.
* The open() function will actually kick the board off.
*/
static int __init wdtpci_init(void)
{
return pci_register_driver (&wdtpci_driver);
}
module_init(wdtpci_init);
module_exit(wdtpci_cleanup);
MODULE_AUTHOR("JP Nollmann, Alan Cox");
MODULE_DESCRIPTION("Driver for the ICS PCI-WDT500/501 watchdog cards");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS_MISCDEV(TEMP_MINOR);