patch-1.3.51 linux/drivers/char/softdog.c

• Lines: 116
• Date: Tue Dec 26 06:19:51 1995
• Orig file: v1.3.50/linux/drivers/char/softdog.c
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.50/linux/drivers/char/softdog.c linux/drivers/char/softdog.c
@@ -0,0 +1,115 @@
+/*
+ *	SoftDog	0.02:	A Software Watchdog Device
+ *
+ *	(c) Copyright 1995    Alan Cox <alan@lxorguk.ukuu.org.uk>
+ *
+ *	Email us for quotes on Linux software and driver development. 
+ *
+ *			-----------------------
+ *
+ *	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.
+ *
+ *			-----------------------
+ *
+ *	Software only watchdog driver. Unlike its big brother the WDT501P
+ *	driver this won't always recover a failed machine.
+ */
+ 
+ 
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/mouse.h>
+#define WATCHDOG_MINOR	130
+#define TIMER_MARGIN	(60*HZ)		/* Allow 1 minute */
+
+/*
+ *	Our timer
+ */
+ 
+struct timer_list watchdog_ticktock;
+static int timer_alive = 0;
+
+
+/*
+ *	If the timer expires..
+ */
+ 
+static void watchdog_fire(long data)
+{
+	extern void hard_reset_now(void);
+	hard_reset_now();
+	printk("WATCHDOG: Reboot didn't ?????\n");
+}
+
+/*
+ *	Allow only one person to hold it open
+ */
+ 
+static int softdog_open(struct inode *inode, struct file *file)
+{
+	if(timer_alive)
+		return -EBUSY;
+	/*
+	 *	Activate timer
+	 */
+	watchdog_ticktock.expires=jiffies+TIMER_MARGIN;
+	add_timer(&watchdog_ticktock);
+	return 0;
+}
+
+static void softdog_release(struct inode *inode, struct file *file)
+{
+	/*
+	 *	Shut off the timer.
+	 */
+	del_timer(&watchdog_ticktock);
+	timer_alive=0;
+}
+
+static int softdog_write(struct inode *inode, struct file *file, const char *data, int len)
+{
+	/*
+	 *	Refresh the timer.
+	 */
+	del_timer(&watchdog_ticktock);
+	watchdog_ticktock.expires=jiffies+TIMER_MARGIN;
+	add_timer(&watchdog_ticktock);
+	return 1;
+}
+
+/*
+ *	The mouse stuff ought to be renamed misc_register etc before 1.4...
+ */
+ 
+void watchdog_init(void)
+{
+	static struct file_operations softdog_fops=
+	{
+		NULL,		/* Seek */
+		NULL,		/* Read */
+		softdog_write,	/* Write */
+		NULL,		/* Readdir */
+		NULL,		/* Select */
+		NULL,		/* Ioctl */
+		NULL,		/* MMap */
+		softdog_open,
+		softdog_release,
+		NULL,		
+		NULL		/* Fasync */
+	};
+	static struct mouse softdog_mouse={
+		WATCHDOG_MINOR,
+		"softdog",
+		&softdog_fops
+	};
+
+	mouse_register(&softdog_mouse);
+	init_timer(&watchdog_ticktock);
+	watchdog_ticktock.function=watchdog_fire;
+	printk("Software Watchdog Timer: 0.02\n");
+}