2 * MixCom Watchdog: A Simple Hardware Watchdog Device
3 * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis
5 * Author: Gergely Madarasz <gorgo@itc.hu>
7 * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu>
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
14 * Version 0.1 (99/04/15):
17 * Version 0.2 (99/06/16):
18 * - added kernel timer watchdog ping after close
19 * since the hardware does not support watchdog shutdown
21 * Version 0.3 (99/06/21):
22 * - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls
24 * Version 0.3.1 (99/06/22):
25 * - allow module removal while internal timer is active,
26 * print warning about probable reset
28 * Version 0.4 (99/11/15):
29 * - support for one more type board
31 * Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com>
32 * - added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
34 * Version 0.6 (2002/04/12): Rob Radez <rob@osinvestor.com>
35 * - make mixcomwd_opened unsigned,
36 * removed lock_kernel/unlock_kernel from mixcomwd_release,
37 * modified ioctl a bit to conform to API
43 #include <linux/module.h>
44 #include <linux/moduleparam.h>
45 #include <linux/types.h>
46 #include <linux/miscdevice.h>
47 #include <linux/ioport.h>
48 #include <linux/watchdog.h>
50 #include <linux/reboot.h>
51 #include <linux/init.h>
52 #include <linux/jiffies.h>
53 #include <linux/timer.h>
54 #include <asm/uaccess.h>
58 * We have two types of cards that can be probed:
59 * 1) The Mixcom cards: these cards can be found at addresses
60 * 0x180, 0x280, 0x380 with an additional offset of 0xc10.
61 * (Or 0xd90, 0xe90, 0xf90).
62 * 2) The FlashCOM cards: these cards can be set up at
63 * 0x300 -> 0x378, in 0x8 jumps with an offset of 0x04.
64 * (Or 0x304 -> 0x37c in 0x8 jumps).
65 * Each card has it's own ID.
67 #define MIXCOM_ID 0x11
68 #define FLASHCOM_ID 0x18
69 static int mixcomwd_ioports[] = { 0xd90, 0xe90, 0xf90, 0x000 };
71 static void mixcomwd_timerfun(unsigned long d);
73 static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */
75 static int watchdog_port;
76 static int mixcomwd_timer_alive;
77 static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun, 0, 0);
78 static char expect_close;
80 static int nowayout = WATCHDOG_NOWAYOUT;
81 module_param(nowayout, int, 0);
82 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
84 static void mixcomwd_ping(void)
86 outb_p(55,watchdog_port);
90 static void mixcomwd_timerfun(unsigned long d)
94 mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
98 * Allow only one person to hold it open
101 static int mixcomwd_open(struct inode *inode, struct file *file)
103 if(test_and_set_bit(0,&mixcomwd_opened)) {
110 * fops_get() code via open() has already done
111 * a try_module_get() so it is safe to do the
114 __module_get(THIS_MODULE);
116 if(mixcomwd_timer_alive) {
117 del_timer(&mixcomwd_timer);
118 mixcomwd_timer_alive=0;
121 return nonseekable_open(inode, file);
124 static int mixcomwd_release(struct inode *inode, struct file *file)
126 if (expect_close == 42) {
127 if(mixcomwd_timer_alive) {
128 printk(KERN_ERR "mixcomwd: release called while internal timer alive");
131 mixcomwd_timer_alive=1;
132 mod_timer(&mixcomwd_timer, jiffies + 5 * HZ);
134 printk(KERN_CRIT "mixcomwd: WDT device closed unexpectedly. WDT will not stop!\n");
137 clear_bit(0,&mixcomwd_opened);
143 static ssize_t mixcomwd_write(struct file *file, const char __user *data, size_t len, loff_t *ppos)
150 /* In case it was set long ago */
153 for (i = 0; i != len; i++) {
155 if (get_user(c, data + i))
166 static int mixcomwd_ioctl(struct inode *inode, struct file *file,
167 unsigned int cmd, unsigned long arg)
169 void __user *argp = (void __user *)arg;
170 int __user *p = argp;
172 static struct watchdog_info ident = {
173 .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
174 .firmware_version = 1,
175 .identity = "MixCOM watchdog",
180 case WDIOC_GETSTATUS:
181 status=mixcomwd_opened;
183 status|=mixcomwd_timer_alive;
185 if (copy_to_user(p, &status, sizeof(int))) {
189 case WDIOC_GETSUPPORT:
190 if (copy_to_user(argp, &ident, sizeof(ident))) {
194 case WDIOC_KEEPALIVE:
203 static const struct file_operations mixcomwd_fops=
205 .owner = THIS_MODULE,
207 .write = mixcomwd_write,
208 .ioctl = mixcomwd_ioctl,
209 .open = mixcomwd_open,
210 .release = mixcomwd_release,
213 static struct miscdevice mixcomwd_miscdev=
215 .minor = WATCHDOG_MINOR,
217 .fops = &mixcomwd_fops,
220 static int __init mixcomwd_checkcard(int port)
224 if (!request_region(port, 1, "MixCOM watchdog")) {
228 id=inb_p(port) & 0x3f;
230 release_region(port, 1);
236 static int __init flashcom_checkcard(int port)
240 if (!request_region(port, 1, "MixCOM watchdog")) {
245 if(id!=FLASHCOM_ID) {
246 release_region(port, 1);
252 static int __init mixcomwd_init(void)
258 for (i = 0; !found && mixcomwd_ioports[i] != 0; i++) {
259 watchdog_port = mixcomwd_checkcard(mixcomwd_ioports[i]);
265 /* The FlashCOM card can be set up at 0x304 -> 0x37c, in 0x8 jumps */
266 for (i = 0x304; !found && i < 0x380; i+=0x8) {
267 watchdog_port = flashcom_checkcard(i);
274 printk("mixcomwd: No card detected, or port not available.\n");
278 ret = misc_register(&mixcomwd_miscdev);
281 release_region(watchdog_port, 1);
285 printk(KERN_INFO "MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",VERSION,watchdog_port);
290 static void __exit mixcomwd_exit(void)
293 if(mixcomwd_timer_alive) {
294 printk(KERN_WARNING "mixcomwd: I quit now, hardware will"
295 " probably reboot!\n");
296 del_timer_sync(&mixcomwd_timer);
297 mixcomwd_timer_alive=0;
300 release_region(watchdog_port,1);
301 misc_deregister(&mixcomwd_miscdev);
304 module_init(mixcomwd_init);
305 module_exit(mixcomwd_exit);
307 MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>");
308 MODULE_DESCRIPTION("MixCom Watchdog driver");
309 MODULE_LICENSE("GPL");
310 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);