patch-2.1.54 linux/drivers/char/acquirewdt.c

• Lines: 222
• Date: Sat Sep 6 10:16:07 1997
• Orig file: v2.1.53/linux/drivers/char/acquirewdt.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.1.53/linux/drivers/char/acquirewdt.c linux/drivers/char/acquirewdt.c
@@ -0,0 +1,221 @@
+/*
+ *	Acquire Single Board Computer Watchdog Timer driver for Linux 2.1.x
+ *
+ *      Based on wdt.c. Original copyright messages:
+ *
+ *	(c) Copyright 1996 Alan Cox <alan@cymru.net>, All Rights Reserved.
+ *				http://www.cymru.net
+ *
+ *	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>
+ *
+ */
+
+#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>
+#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>
+
+static int acq_is_open=0;
+
+/*
+ *	You must set these - there is no sane way to probe for this board.
+ */
+ 
+#define WDT_STOP 0x43
+#define WDT_START 0x443
+#define WATCHDOG_MINOR 130
+
+#define WD_TIMO (100*60)		/* 1 minute */
+
+
+/*
+ *	Kernel methods.
+ */
+ 
+
+static void acq_ping(void)
+{
+	/* Write a watchdog value */
+	inb_p(WDT_START);
+}
+
+static long acq_write(struct inode *inode, struct file *file, const char *buf, unsigned long count)
+{
+	if(count)
+	{
+		acq_ping();
+		return 1;
+	}
+	return 0;
+}
+
+static long acq_read(struct inode *inode, struct file *file, char *buf, unsigned long count)
+{
+	return -EINVAL;
+}
+
+
+
+static int acq_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
+	unsigned long arg)
+{
+	static struct watchdog_info ident=
+	{
+		WDIOF_KEEPALIVEPING, 1, "Acquire WDT"
+	};
+	
+	switch(cmd)
+	{
+	case WDIOC_GETSUPPORT:
+	  if (copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident)))
+	    return -EFAULT;
+	  break;
+	  
+	case WDIOC_GETSTATUS:
+	  if (copy_to_user((int *)arg, &acq_is_open,  sizeof(int)))
+	    return -EFAULT;
+	  break;
+
+	case WDIOC_KEEPALIVE:
+	  acq_ping();
+	  break;
+
+	default:
+	  return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static int acq_open(struct inode *inode, struct file *file)
+{
+	switch(MINOR(inode->i_rdev))
+	{
+		case WATCHDOG_MINOR:
+			if(acq_is_open)
+				return -EBUSY;
+			MOD_INC_USE_COUNT;
+			/*
+			 *	Activate 
+			 */
+	 
+			acq_is_open=1;
+			inb_p(WDT_START);      
+			return 0;
+		default:
+			return -ENODEV;
+	}
+}
+
+static int acq_close(struct inode *inode, struct file *file)
+{
+	if(MINOR(inode->i_rdev)==WATCHDOG_MINOR)
+	{
+#ifndef CONFIG_WATCHDOG_NOWAYOUT	
+		inb_p(WDT_STOP);
+#endif		
+		acq_is_open=0;
+	}
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+/*
+ *	Notifier for system down
+ */
+
+static int acq_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_STOP);
+	}
+	return NOTIFY_DONE;
+}
+ 
+/*
+ *	Kernel Interfaces
+ */
+ 
+ 
+static struct file_operations acq_fops = {
+	NULL,
+	acq_read,
+	acq_write,
+	NULL,		/* No Readdir */
+	NULL,		/* No Select */
+	acq_ioctl,
+	NULL,		/* No mmap */
+	acq_open,
+	acq_close
+};
+
+static struct miscdevice acq_miscdev=
+{
+	WATCHDOG_MINOR,
+	"Acquire WDT",
+	&acq_fops
+};
+
+
+/*
+ *	The WDT card needs to learn about soft shutdowns in order to
+ *	turn the timebomb registers off. 
+ */
+ 
+static struct notifier_block acq_notifier=
+{
+	acq_notify_sys,
+	NULL,
+	0
+};
+
+#ifdef MODULE
+
+#define acq_init init_module
+
+void cleanup_module(void)
+{
+	misc_deregister(&acq_miscdev);
+	unregister_reboot_notifier(&acq_notifier);
+	release_region(WDT_STOP,1);
+	release_region(WDT_START,1);
+}
+
+#endif
+
+__initfunc(int acq_init(void))
+{
+	printk("WDT driver for Acquire single board computer initialising.\n");
+
+	misc_register(&acq_miscdev);
+	request_region(WDT_STOP, 1, "Acquire WDT");
+	request_region(WDT_START, 1, "Acquire WDT");
+	unregister_reboot_notifier(&acq_notifier);
+	return 0;
+}
+