patch-2.3.99-pre4 linux/drivers/char/wdt_pci.c

• Lines: 559
• Date: Sun Apr 2 15:38:53 2000
• Orig file: v2.3.99-pre3/linux/drivers/char/wdt_pci.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.99-pre3/linux/drivers/char/wdt_pci.c linux/drivers/char/wdt_pci.c
@@ -0,0 +1,558 @@
+/*
+ *	Industrial Computer Source WDT500/501 driver for Linux 2.1.x
+ *
+ *	(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 0.08.
+ *
+ *	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
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/types.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#define WDT_IS_PCI
+#include "wd501p.h"
+#include <linux/malloc.h>
+#include <linux/ioport.h>
+#include <linux/fcntl.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <linux/notifier.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+
+#include <linux/pci.h>
+
+/*
+ * 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
+
+static int wdt_is_open=0;
+
+/*
+ *	You must set these - there is no sane way to probe for this board.
+ *	You can use wdt=x,y to set these now.
+ */
+ 
+static int io=0x240;
+static int irq=11;
+
+#define WD_TIMO (100*60)		/* 1 minute */
+
+#ifndef MODULE
+
+/**
+ *	wdtpci_setup:
+ *	@str: command line string
+ *
+ *	Setup options. The board isn't really probe-able so we have to
+ *	get the user to tell us the configuration. Sane people build it 
+ *	modular but the others come here.
+ */
+ 
+static int __init wdtpci_setup(char *str)
+{
+	int ints[4];
+
+	str = get_options (str, ARRAY_SIZE(ints), ints);
+
+	if (ints[0] > 0)
+	{
+		io = ints[1];
+		if(ints[0] > 1)
+			irq = ints[2];
+	}
+
+	return 1;
+}
+
+__setup("wdt=", wdtpci_setup);
+
+#endif /* !MODULE */
+ 
+/*
+ *	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);
+}
+
+/*
+ *	Kernel methods.
+ */
+ 
+ 
+/**
+ *	wdtpci_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_status(void)
+{
+	/*
+	 *	Status register to bit flags
+	 */
+	 
+	int flag=0;
+	unsigned char status=inb_p(WDT_SR);
+	status|=FEATUREMAP1;
+	status&=~FEATUREMAP2;	
+	
+	if(!(status&WDC_SR_TGOOD))
+		flag|=WDIOF_OVERHEAT;
+	if(!(status&WDC_SR_PSUOVER))
+		flag|=WDIOF_POWEROVER;
+	if(!(status&WDC_SR_PSUUNDR))
+		flag|=WDIOF_POWERUNDER;
+	if(!(status&WDC_SR_FANGOOD))
+		flag|=WDIOF_FANFAULT;
+	if(status&WDC_SR_ISOI0)
+		flag|=WDIOF_EXTERN1;
+	if(status&WDC_SR_ISII1)
+		flag|=WDIOF_EXTERN2;
+	return flag;
+}
+
+/**
+ *	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 occuring.
+ */
+ 
+static void 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);
+	
+	status|=FEATUREMAP1;
+	status&=~FEATUREMAP2;	
+	
+	printk(KERN_CRIT "WDT status %d\n", status);
+	
+	if(!(status&WDC_SR_TGOOD))
+		printk(KERN_CRIT "Overheat alarm.(%d)\n",inb_p(WDT_RT));
+	if(!(status&WDC_SR_PSUOVER))
+		printk(KERN_CRIT "PSU over voltage.\n");
+	if(!(status&WDC_SR_PSUUNDR))
+		printk(KERN_CRIT "PSU under voltage.\n");
+	if(!(status&WDC_SR_FANGOOD))
+		printk(KERN_CRIT "Possible fan fault.\n");
+	if(!(status&WDC_SR_WCCR))
+#ifdef SOFTWARE_REBOOT
+#ifdef ONLY_TESTING
+		printk(KERN_CRIT "Would Reboot.\n");
+#else		
+		printk(KERN_CRIT "Initiating system reboot.\n");
+		machine_restart(NULL);
+#endif		
+#else
+		printk(KERN_CRIT "Reset in 5ms.\n");
+#endif		
+}
+
+
+static long long wdtpci_llseek(struct file *file, long long offset, int origin)
+{
+	return -ESPIPE;
+}
+
+/**
+ *	wdtpci_ping:
+ *
+ *	Reload counter one with the watchdog timeout. We don't bother reloading
+ *	the cascade counter. 
+ */
+ 
+static void wdtpci_ping(void)
+{
+	/* Write a watchdog value */
+	inb_p(WDT_DC);
+	wdtpci_ctr_mode(1,2);
+	wdtpci_ctr_load(1,WD_TIMO);		/* Timeout */
+	outb_p(0, WDT_DC);
+}
+
+/**
+ *	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 *buf, size_t count, loff_t *ppos)
+{
+	/*  Can't seek (pwrite) on this device  */
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+
+	if(count)
+	{
+		wdtpci_ping();
+		return 1;
+	}
+	return 0;
+}
+
+/**
+ *	wdtpci_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
+ *	farenheit. It was designed by an imperial measurement luddite.
+ */
+ 
+static ssize_t wdtpci_read(struct file *file, char *buf, size_t count, loff_t *ptr)
+{
+	unsigned short c=inb_p(WDT_RT);
+	unsigned char cp;
+	
+	/*  Can't seek (pread) on this device  */
+	if (ptr != &file->f_pos)
+		return -ESPIPE;
+
+	switch(MINOR(file->f_dentry->d_inode->i_rdev))
+	{
+		case TEMP_MINOR:
+			c*=11;
+			c/=15;
+			cp=c+7;
+			if(copy_to_user(buf,&cp,1))
+				return -EFAULT;
+			return 1;
+		default:
+			return -EINVAL;
+	}
+}
+
+/**
+ *	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)
+{
+	static struct watchdog_info ident=
+	{
+		WDIOF_OVERHEAT|WDIOF_POWERUNDER|WDIOF_POWEROVER
+			|WDIOF_EXTERN1|WDIOF_EXTERN2|WDIOF_FANFAULT,
+		1,
+		"WDT500/501PCI"
+	};
+	
+	ident.options&=WDT_OPTION_MASK;	/* Mask down to the card we have */
+	switch(cmd)
+	{
+		default:
+			return -ENOIOCTLCMD;
+		case WDIOC_GETSUPPORT:
+			return copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident))?-EFAULT:0;
+
+		case WDIOC_GETSTATUS:
+			return put_user(wdtpci_status(),(int *)arg);
+		case WDIOC_GETBOOTSTATUS:
+			return put_user(0, (int *)arg);
+		case WDIOC_KEEPALIVE:
+			wdtpci_ping();
+			return 0;
+	}
+}
+
+/**
+ *	wdtpci_open:
+ *	@inode: inode of device
+ *	@file: file handle to device
+ *
+ *	One of our two misc devices 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)
+{
+	switch(MINOR(inode->i_rdev))
+	{
+		case WATCHDOG_MINOR:
+			if(wdt_is_open)
+				return -EBUSY;
+			MOD_INC_USE_COUNT;
+			/*
+			 *	Activate 
+			 */
+	 
+			wdt_is_open=1;
+
+			inb_p(WDT_DC);		/* Disable */
+
+			/*
+			 * "pet" the watchdog, as Access says.
+			 * This resets the clock outputs.
+			 */
+				
+			wdtpci_ctr_mode(2,0);
+			outb_p(0, WDT_DC);
+
+			inb_p(WDT_DC);
+
+			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);
+			wdtpci_ctr_mode(1,2);
+			wdtpci_ctr_mode(2,1);
+			wdtpci_ctr_load(0,20833);	/* count at 100Hz */
+			wdtpci_ctr_load(1,WD_TIMO);/* Timeout 60 seconds */
+			/* DO NOT LOAD CTR2 on PCI card! -- JPN */
+			outb_p(0, WDT_DC);	/* Enable */
+			return 0;
+		case TEMP_MINOR:
+			MOD_INC_USE_COUNT;
+			return 0;
+		default:
+			return -ENODEV;
+	}
+}
+
+/**
+ *	wdtpci_close:
+ *	@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(MINOR(inode->i_rdev)==WATCHDOG_MINOR)
+	{
+#ifndef CONFIG_WATCHDOG_NOWAYOUT	
+		inb_p(WDT_DC);		/* Disable counters */
+		wdtpci_ctr_load(2,0);	/* 0 length reset pulses now */
+#endif		
+		wdt_is_open=0;
+	}
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+/**
+ *	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 */
+		inb_p(WDT_DC);
+		wdtpci_ctr_load(2,0);
+	}
+	return NOTIFY_DONE;
+}
+ 
+/*
+ *	Kernel Interfaces
+ */
+ 
+ 
+static struct file_operations wdtpci_fops = {
+	llseek:		wdtpci_llseek,
+	read:		wdtpci_read,
+	write:		wdtpci_write,
+	ioctl:		wdtpci_ioctl,
+	open:		wdtpci_open,
+	release:	wdtpci_release,
+};
+
+static struct miscdevice wdtpci_miscdev=
+{
+	WATCHDOG_MINOR,
+	"watchdog",
+	&wdtpci_fops
+};
+
+#ifdef CONFIG_WDT_501
+static struct miscdevice temp_miscdev=
+{
+	TEMP_MINOR,
+	"temperature",
+	&wdtpci_fops
+};
+#endif
+
+/*
+ *	The WDT card needs to learn about soft shutdowns in order to
+ *	turn the timebomb registers off. 
+ */
+ 
+static struct notifier_block wdtpci_notifier=
+{
+	wdtpci_notify_sys,
+	NULL,
+	0
+};
+
+#ifdef MODULE
+
+#define wdtpci_init init_module
+
+/**
+ *	cleanup_module:
+ *
+ *	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 60 seconds or reboot.
+ */
+ 
+void cleanup_module(void)
+{
+	misc_deregister(&wdtpci_miscdev);
+#ifdef CONFIG_WDT_501_PCI
+	misc_deregister(&temp_miscdev);
+#endif	
+	unregister_reboot_notifier(&wdtpci_notifier);
+	release_region(io,16);
+	free_irq(irq, &wdtpci_miscdev);
+}
+
+#endif
+
+/**
+ * 	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.
+ */
+ 
+int __init wdtpci_init(void)
+{
+ 	struct pci_dev *dev = NULL;
+ 
+ 	if (pci_present()) 
+ 	{
+ 		while ((dev = pci_find_device(PCI_VENDOR_ID_ACCESSIO,
+ 					     PCI_DEVICE_ID_WDG_CSM, dev))) {
+ 			/* See if we can do this device */
+ 			irq = dev->irq;
+			io = dev->resource[2].start;
+ 			printk("WDT501-P(PCI-WDG-CSM) driver 0.07 at %X "
+			       "(Interrupt %d)\n", io, irq);
+ 		}
+ 	}
+	if(request_region(io, 16, "wdt-pci")==NULL)
+	{
+		printk(KERN_ERR "I/O %d is not free.\n", io);
+		return -EIO;
+	}
+	if(request_irq(irq, wdtpci_interrupt, SA_INTERRUPT|SA_SHIRQ, "wdt-pci", &wdtpci_miscdev))
+	{
+		printk(KERN_ERR "IRQ %d is not free.\n", irq);
+		release_region(io, 16);
+		return -EIO;
+	}
+	misc_register(&wdtpci_miscdev);
+#ifdef CONFIG_WDT_501	
+	misc_register(&temp_miscdev);
+#endif	
+	register_reboot_notifier(&wdtpci_notifier);
+	return 0;
+}
+