patch-2.4.19 linux-2.4.19/drivers/char/indydog.c

• Lines: 156
• Date: Fri Aug 2 17:39:43 2002
• Orig file: linux-2.4.18/drivers/char/indydog.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -urN linux-2.4.18/drivers/char/indydog.c linux-2.4.19/drivers/char/indydog.c
@@ -0,0 +1,155 @@
+/*
+ *	IndyDog	0.2	A Hardware Watchdog Device for SGI IP22
+ *
+ *	(c) Copyright 2002 Guido Guenther <agx@sigxcpu.org>, All Rights Reserved.
+ *
+ *	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.
+ *	
+ *	based on softdog.c by Alan Cox <alan@redhat.com>
+ */
+ 
+#include <linux/module.h>
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/watchdog.h>
+#include <linux/smp_lock.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <asm/sgi/sgimc.h>
+
+static unsigned long indydog_alive;
+static struct sgimc_misc_ctrl *mcmisc_regs; 
+
+static void indydog_ping()
+{
+	mcmisc_regs->watchdogt = 0;
+}
+
+
+/*
+ *	Allow only one person to hold it open
+ */
+
+static int indydog_open(struct inode *inode, struct file *file)
+{
+	u32 mc_ctrl0;
+	
+	if( test_and_set_bit(0,&indydog_alive) )
+		return -EBUSY;
+#ifdef CONFIG_WATCHDOG_NOWAYOUT
+	MOD_INC_USE_COUNT;
+#endif
+	/*
+	 *	Activate timer
+	 */
+	mcmisc_regs = (struct sgimc_misc_ctrl *)(KSEG1+0x1fa00000);
+
+	mc_ctrl0 = mcmisc_regs->cpuctrl0 | SGIMC_CCTRL0_WDOG;
+	mcmisc_regs->cpuctrl0 = mc_ctrl0;
+	indydog_ping();
+			
+	printk("Started watchdog timer.\n");
+	return 0;
+}
+
+static int indydog_release(struct inode *inode, struct file *file)
+{
+	/*
+	 *	Shut off the timer.
+	 * 	Lock it in if it's a module and we defined ...NOWAYOUT
+	 */
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+	{
+	u32 mc_ctrl0 = mcmisc_regs->cpuctrl0; 
+	mc_ctrl0 &= ~SGIMC_CCTRL0_WDOG;
+	mcmisc_regs->cpuctrl0 = mc_ctrl0;
+	printk("Stopped watchdog timer.\n");
+	}
+#endif
+	clear_bit(0,&indydog_alive);
+	return 0;
+}
+
+static ssize_t indydog_write(struct file *file, const char *data, size_t len, loff_t *ppos)
+{
+	/*  Can't seek (pwrite) on this device  */
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+
+	/*
+	 *	Refresh the timer.
+	 */
+	if(len) {
+		indydog_ping();
+		return 1;
+	}
+	return 0;
+}
+
+static int indydog_ioctl(struct inode *inode, struct file *file,
+	unsigned int cmd, unsigned long arg)
+{
+	static struct watchdog_info ident = {
+		identity: "Hardware Watchdog for SGI IP22",
+	};
+	switch (cmd) {
+		default:
+			return -ENOIOCTLCMD;
+		case WDIOC_GETSUPPORT:
+			if(copy_to_user((struct watchdog_info *)arg, &ident, sizeof(ident)))
+				return -EFAULT;
+			return 0;
+		case WDIOC_GETSTATUS:
+		case WDIOC_GETBOOTSTATUS:
+			return put_user(0,(int *)arg);
+		case WDIOC_KEEPALIVE:
+			indydog_ping();
+			return 0;
+	}
+}
+
+static struct file_operations indydog_fops = {
+	owner:		THIS_MODULE,
+	write:		indydog_write,
+	ioctl:		indydog_ioctl,
+	open:		indydog_open,
+	release:	indydog_release,
+};
+
+static struct miscdevice indydog_miscdev = {
+	minor:		WATCHDOG_MINOR,
+	name:		"watchdog",
+	fops:		&indydog_fops,
+};
+
+static const char banner[] __initdata = KERN_INFO "Hardware Watchdog Timer for SGI IP22: 0.2\n";
+
+static int __init watchdog_init(void)
+{
+	int ret;
+
+	ret = misc_register(&indydog_miscdev);
+
+	if (ret)
+		return ret;
+
+	printk(banner);
+
+	return 0;
+}
+
+static void __exit watchdog_exit(void)
+{
+	misc_deregister(&indydog_miscdev);
+}
+
+module_init(watchdog_init);
+module_exit(watchdog_exit);
+MODULE_LICENSE("GPL");