patch-2.3.41 linux/drivers/char/mixcomwd.c

• Lines: 251
• Date: Sat Jan 22 12:31:10 2000
• Orig file: v2.3.40/linux/drivers/char/mixcomwd.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.40/linux/drivers/char/mixcomwd.c linux/drivers/char/mixcomwd.c
@@ -0,0 +1,250 @@
+/*
+ * MixCom Watchdog: A Simple Hardware Watchdog Device
+ * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis
+ *
+ * Author: Gergely Madarasz <gorgo@itc.hu>
+ *
+ * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu>
+ *
+ * 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.
+ *
+ * Version 0.1 (99/04/15):
+ *		- first version
+ *
+ * Version 0.2 (99/06/16):
+ *		- added kernel timer watchdog ping after close
+ *		  since the hardware does not support watchdog shutdown
+ *
+ * Version 0.3 (99/06/21):
+ *		- added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls
+ *
+ * Version 0.3.1 (99/06/22):
+ *		- allow module removal while internal timer is active,
+ *		  print warning about probable reset
+ *	
+ */
+
+#define VERSION "0.3.1" 
+  
+#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/ioport.h>
+#include <linux/watchdog.h>
+#include <linux/reboot.h>
+#include <linux/init.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+static int mixcomwd_ioports[] = { 0x180, 0x280, 0x380, 0x000 };
+
+#define MIXCOM_WATCHDOG_OFFSET 0xc10
+#define MIXCOM_ID1 0x11
+#define MIXCOM_ID2 0x13
+
+static int mixcomwd_opened;
+static int mixcomwd_port;
+
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+static int mixcomwd_timer_alive;
+static struct timer_list mixcomwd_timer;
+#endif
+
+static void mixcomwd_ping(void)
+{
+	outb_p(55,mixcomwd_port+MIXCOM_WATCHDOG_OFFSET);
+	return;
+}
+
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+static void mixcomwd_timerfun(unsigned long d)
+{
+	mixcomwd_ping();
+	
+	mod_timer(&mixcomwd_timer,jiffies+ 5*HZ);
+}
+#endif
+
+/*
+ *	Allow only one person to hold it open
+ */
+ 
+static int mixcomwd_open(struct inode *inode, struct file *file)
+{
+	if(test_and_set_bit(0,&mixcomwd_opened)) {
+		return -EBUSY;
+	}
+	mixcomwd_ping();
+	
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+	if(mixcomwd_timer_alive) {
+		del_timer(&mixcomwd_timer);
+		mixcomwd_timer_alive=0;
+	} 
+#endif
+	MOD_INC_USE_COUNT;
+
+	return 0;
+}
+
+static int mixcomwd_release(struct inode *inode, struct file *file)
+{
+
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+	if(mixcomwd_timer_alive) {
+		printk(KERN_ERR "mixcomwd: release called while internal timer alive");
+		return -EBUSY;
+	}
+	init_timer(&mixcomwd_timer);
+	mixcomwd_timer.expires=jiffies + 5 * HZ;
+	mixcomwd_timer.function=mixcomwd_timerfun;
+	mixcomwd_timer.data=0;
+	mixcomwd_timer_alive=1;
+	add_timer(&mixcomwd_timer);
+#endif
+	MOD_DEC_USE_COUNT;
+
+	clear_bit(0,&mixcomwd_opened);
+	return 0;
+}
+
+
+static ssize_t mixcomwd_write(struct file *file, const char *data, size_t len, loff_t *ppos)
+{
+	if (ppos != &file->f_pos) {
+		return -ESPIPE;
+	}
+
+	if(len)
+	{
+		mixcomwd_ping();
+		return 1;
+	}
+	return 0;
+}
+
+static int mixcomwd_ioctl(struct inode *inode, struct file *file,
+	unsigned int cmd, unsigned long arg)
+{
+	int status;
+        static struct watchdog_info ident = {
+		WDIOF_KEEPALIVEPING, 1, "MixCOM watchdog"
+	};
+                                        
+	switch(cmd)
+	{
+		case WDIOC_GETSTATUS:
+			status=mixcomwd_opened;
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+			status|=mixcomwd_timer_alive;
+#endif
+			if (copy_to_user((int *)arg, &status, sizeof(int))) {
+				return -EFAULT;
+			}
+			break;
+		case WDIOC_GETSUPPORT:
+			if (copy_to_user((struct watchdog_info *)arg, &ident, 
+			    sizeof(ident))) {
+				return -EFAULT;
+			}
+			break;
+		case WDIOC_KEEPALIVE:
+			mixcomwd_ping();
+			break;
+		default:
+			return -ENOIOCTLCMD;
+	}
+	return 0;
+}
+
+static struct file_operations mixcomwd_fops=
+{
+	NULL,		/* Seek */
+	NULL,		/* Read */
+	mixcomwd_write,	/* Write */
+	NULL,		/* Readdir */
+	NULL,		/* Select */
+	mixcomwd_ioctl,	/* Ioctl */
+	NULL,		/* MMap */
+	mixcomwd_open,
+	NULL,		/* flush */
+	mixcomwd_release,
+	NULL,		
+	NULL		/* Fasync */
+};
+
+static struct miscdevice mixcomwd_miscdev=
+{
+	WATCHDOG_MINOR,
+	"watchdog",
+	&mixcomwd_fops
+};
+
+static int __init mixcomwd_checkcard(int port)
+{
+	int id;
+
+	if(check_region(port,1)) {
+		return 0;
+	}
+	
+	id=inb_p(port + MIXCOM_WATCHDOG_OFFSET) & 0x3f;
+	if(id!=MIXCOM_ID1 && id!=MIXCOM_ID2) {
+		return 0;
+	}
+	return 1;
+}
+
+
+void __init mixcomwd_init(void)
+{
+	int i;
+	int found=0;
+
+	for (i = 0; mixcomwd_ioports[i] != 0; i++) {
+		if (mixcomwd_checkcard(mixcomwd_ioports[i])) {
+			found = 1;
+			mixcomwd_port = mixcomwd_ioports[i];
+			break;
+		}
+	}
+
+	if (!found) {
+		printk("mixcomwd: No card detected, or port not available.\n");
+		return;
+	}
+
+	request_region(mixcomwd_port+MIXCOM_WATCHDOG_OFFSET,1,"MixCOM watchdog");
+	
+	misc_register(&mixcomwd_miscdev);
+	printk("MixCOM watchdog driver v%s, MixCOM card at 0x%3x\n",VERSION,mixcomwd_port);
+}	
+
+#ifdef MODULE
+int init_module(void)
+{
+	mixcomwd_init();
+	return 0;
+}
+
+void cleanup_module(void)
+{
+#ifndef CONFIG_WATCHDOG_NOWAYOUT
+	if(mixcomwd_timer_alive) {
+		printk(KERN_WARNING "mixcomwd: I quit now, hardware will"
+			" probably reboot!\n");
+		del_timer(&mixcomwd_timer);
+		mixcomwd_timer_alive=0;
+	}
+#endif
+	release_region(mixcomwd_port+MIXCOM_WATCHDOG_OFFSET,1);
+	misc_deregister(&mixcomwd_miscdev);
+}
+#endif