2 * w83697hf/hg WDT driver
4 * (c) Copyright 2006 Marcus Junker <junker@anduras.de>
6 * Based on w83627hf_wdt.c which is based on advantechwdt.c
7 * which is based on wdt.c.
8 * Original copyright messages:
10 * (c) Copyright 2003 Pádraig Brady <P@draigBrady.com>
12 * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
14 * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
15 * http://www.redhat.com
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
22 * Neither Marcus Junker nor ANDURAS AG admit liability nor provide
23 * warranty for any of this software. This material is provided
24 * "AS-IS" and at no charge.
27 #include <linux/module.h>
28 #include <linux/moduleparam.h>
29 #include <linux/types.h>
30 #include <linux/miscdevice.h>
31 #include <linux/watchdog.h>
33 #include <linux/ioport.h>
34 #include <linux/notifier.h>
35 #include <linux/reboot.h>
36 #include <linux/init.h>
37 #include <linux/spinlock.h>
40 #include <asm/uaccess.h>
41 #include <asm/system.h>
43 #define WATCHDOG_NAME "w83697hf/hg WDT"
44 #define PFX WATCHDOG_NAME ": "
45 #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
47 static unsigned long wdt_is_open;
48 static char expect_close;
49 static spinlock_t io_lock;
51 /* You must set this - there is no sane way to probe for this board. */
52 static int wdt_io = 0x2E;
53 module_param(wdt_io, int, 0);
54 MODULE_PARM_DESC(wdt_io, "w83697hf WDT io port (default 0x2E)");
56 static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
57 module_param(timeout, int, 0);
58 MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
60 static int nowayout = WATCHDOG_NOWAYOUT;
61 module_param(nowayout, int, 0);
62 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
68 #define W83697HF_EFER (wdt_io+0) /* Extended Function Enable Register */
69 #define W83697HF_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */
70 #define W83697HF_EFDR (wdt_io+1) /* Extended Function Data Register */
73 w83697hf_select_wd_register(void)
75 outb_p(0x87, W83697HF_EFER); /* Enter extended function mode */
76 outb_p(0x87, W83697HF_EFER); /* Again according to manual */
78 outb_p(0x29, W83697HF_EFER); /* select CR29 */
79 outb_p(0x20, W83697HF_EFDR); /* select WDTO */
81 outb_p(0x07, W83697HF_EFER); /* point to logical device number reg */
82 outb_p(0x08, W83697HF_EFDR); /* select logical device 8 (GPIO2) */
83 outb_p(0x30, W83697HF_EFER); /* select CR30 */
84 outb_p(0x01, W83697HF_EFDR); /* set bit 0 to activate GPIO2 */
88 w83697hf_unselect_wd_register(void)
90 outb_p(0xAA, W83697HF_EFER); /* Leave extended function mode */
98 w83697hf_select_wd_register();
100 outb_p(0xF3, W83697HF_EFER); /* Select CRF3 */
102 t=inb_p(W83697HF_EFDR); /* read CRF3 */
104 printk (KERN_INFO PFX "Watchdog already running. Resetting timeout to %d sec\n", timeout);
105 outb_p(timeout, W83697HF_EFDR); /* Write back to CRF3 */
107 outb_p(0xF4, W83697HF_EFER); /* Select CRF4 */
108 t=inb_p(W83697HF_EFDR); /* read CRF4 */
109 t&=~0x0C; /* set second mode & disable keyboard turning off watchdog */
110 outb_p(t, W83697HF_EFDR); /* Write back to CRF4 */
112 w83697hf_unselect_wd_register();
116 wdt_ctrl(int timeout)
120 w83697hf_select_wd_register();
122 outb_p(0xF4, W83697HF_EFER); /* Select CRF4 */
123 outb_p(timeout, W83697HF_EFDR); /* Write Timeout counter to CRF4 */
125 w83697hf_unselect_wd_register();
127 spin_unlock(&io_lock);
145 wdt_set_heartbeat(int t)
147 if ((t < 1) || (t > 255))
155 wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
163 for (i = 0; i != count; i++) {
165 if (get_user(c, buf+i))
177 wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd,
180 void __user *argp = (void __user *)arg;
181 int __user *p = argp;
183 static struct watchdog_info ident = {
184 .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
185 .firmware_version = 1,
186 .identity = "W83697HF WDT",
190 case WDIOC_GETSUPPORT:
191 if (copy_to_user(argp, &ident, sizeof(ident)))
195 case WDIOC_GETSTATUS:
196 case WDIOC_GETBOOTSTATUS:
197 return put_user(0, p);
199 case WDIOC_KEEPALIVE:
203 case WDIOC_SETTIMEOUT:
204 if (get_user(new_timeout, p))
206 if (wdt_set_heartbeat(new_timeout))
211 case WDIOC_GETTIMEOUT:
212 return put_user(timeout, p);
214 case WDIOC_SETOPTIONS:
216 int options, retval = -EINVAL;
218 if (get_user(options, p))
221 if (options & WDIOS_DISABLECARD) {
226 if (options & WDIOS_ENABLECARD) {
241 wdt_open(struct inode *inode, struct file *file)
243 if (test_and_set_bit(0, &wdt_is_open))
250 return nonseekable_open(inode, file);
254 wdt_close(struct inode *inode, struct file *file)
256 if (expect_close == 42) {
259 printk (KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
263 clear_bit(0, &wdt_is_open);
268 * Notifier for system down
272 wdt_notify_sys(struct notifier_block *this, unsigned long code,
275 if (code == SYS_DOWN || code == SYS_HALT) {
276 /* Turn the WDT off */
286 static struct file_operations wdt_fops = {
287 .owner = THIS_MODULE,
292 .release = wdt_close,
295 static struct miscdevice wdt_miscdev = {
296 .minor = WATCHDOG_MINOR,
302 * The WDT needs to learn about soft shutdowns in order to
303 * turn the timebomb registers off.
306 static struct notifier_block wdt_notifier = {
307 .notifier_call = wdt_notify_sys,
315 spin_lock_init(&io_lock);
317 printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n");
319 if (wdt_set_heartbeat(timeout)) {
320 wdt_set_heartbeat(WATCHDOG_TIMEOUT);
321 printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n",
325 if (!request_region(wdt_io, 2, WATCHDOG_NAME)) {
326 printk (KERN_ERR PFX "I/O address 0x%04x already in use\n",
334 ret = register_reboot_notifier(&wdt_notifier);
336 printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
341 ret = misc_register(&wdt_miscdev);
343 printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
344 WATCHDOG_MINOR, ret);
348 printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
354 unregister_reboot_notifier(&wdt_notifier);
356 release_region(wdt_io, 2);
363 misc_deregister(&wdt_miscdev);
364 unregister_reboot_notifier(&wdt_notifier);
365 release_region(wdt_io, 2);
368 module_init(wdt_init);
369 module_exit(wdt_exit);
371 MODULE_LICENSE("GPL");
372 MODULE_AUTHOR("Marcus Junker <junker@anduras.de>");
373 MODULE_DESCRIPTION("w83697hf/hg WDT driver");
374 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);