2 * Wdt977 0.04: A Watchdog Device for Netwinder W83977AF chip
4 * (c) Copyright 1998 Rebel.com (Woody Suwalski <woody@netwinder.org>)
6 * -----------------------
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version
11 * 2 of the License, or (at your option) any later version.
13 * -----------------------
14 * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
15 * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
16 * 19-Dec-2001 Woody Suwalski: Netwinder fixes, ioctl interface
17 * 06-Jan-2002 Woody Suwalski: For compatibility, convert all timeouts
18 * from minutes to seconds.
19 * 07-Jul-2003 Daniele Bellucci: Audit return code of misc_register in
21 * 25-Oct-2005 Woody Suwalski: Convert addresses to #defs, add spinlocks
22 * remove limitiation to be used on Netwinders only
25 #include <linux/module.h>
26 #include <linux/moduleparam.h>
27 #include <linux/types.h>
28 #include <linux/kernel.h>
30 #include <linux/miscdevice.h>
31 #include <linux/init.h>
32 #include <linux/ioport.h>
33 #include <linux/watchdog.h>
34 #include <linux/notifier.h>
35 #include <linux/reboot.h>
38 #include <asm/system.h>
39 #include <asm/mach-types.h>
40 #include <asm/uaccess.h>
42 #define WATCHDOG_VERSION "0.04"
43 #define WATCHDOG_NAME "Wdt977"
44 #define PFX WATCHDOG_NAME ": "
45 #define DRIVER_VERSION WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n"
47 #define IO_INDEX_PORT 0x370 /* on some systems it can be 0x3F0 */
48 #define IO_DATA_PORT (IO_INDEX_PORT+1)
50 #define UNLOCK_DATA 0x87
51 #define LOCK_DATA 0xAA
52 #define DEVICE_REGISTER 0x07
55 #define DEFAULT_TIMEOUT 60 /* default timeout in seconds */
57 static int timeout = DEFAULT_TIMEOUT;
58 static int timeoutM; /* timeout in minutes */
59 static unsigned long timer_alive;
61 static char expect_close;
62 static spinlock_t spinlock;
64 module_param(timeout, int, 0);
65 MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (60..15300), default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")");
66 module_param(testmode, int, 0);
67 MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0");
69 static int nowayout = WATCHDOG_NOWAYOUT;
70 module_param(nowayout, int, 0);
71 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)");
77 static int wdt977_start(void)
81 spin_lock_irqsave(&spinlock, flags);
83 /* unlock the SuperIO chip */
84 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
85 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
87 /* select device Aux2 (device=8) and set watchdog regs F2, F3 and F4
88 * F2 has the timeout in minutes
89 * F3 could be set to the POWER LED blink (with GP17 set to PowerLed)
90 * at timeout, and to reset timer on kbd/mouse activity (not impl.)
91 * F4 is used to just clear the TIMEOUT'ed state (bit 0)
93 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
94 outb_p(0x08, IO_DATA_PORT);
95 outb_p(0xF2, IO_INDEX_PORT);
96 outb_p(timeoutM, IO_DATA_PORT);
97 outb_p(0xF3, IO_INDEX_PORT);
98 outb_p(0x00, IO_DATA_PORT); /* another setting is 0E for kbd/mouse/LED */
99 outb_p(0xF4, IO_INDEX_PORT);
100 outb_p(0x00, IO_DATA_PORT);
102 /* at last select device Aux1 (dev=7) and set GP16 as a watchdog output */
103 /* in test mode watch the bit 1 on F4 to indicate "triggered" */
106 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
107 outb_p(0x07, IO_DATA_PORT);
108 outb_p(0xE6, IO_INDEX_PORT);
109 outb_p(0x08, IO_DATA_PORT);
112 /* lock the SuperIO chip */
113 outb_p(LOCK_DATA, IO_INDEX_PORT);
115 spin_unlock_irqrestore(&spinlock, flags);
116 printk(KERN_INFO PFX "activated.\n");
125 static int wdt977_stop(void)
128 spin_lock_irqsave(&spinlock, flags);
130 /* unlock the SuperIO chip */
131 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
132 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
134 /* select device Aux2 (device=8) and set watchdog regs F2,F3 and F4
135 * F3 is reset to its default state
136 * F4 can clear the TIMEOUT'ed state (bit 0) - back to default
137 * We can not use GP17 as a PowerLed, as we use its usage as a RedLed
139 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
140 outb_p(0x08, IO_DATA_PORT);
141 outb_p(0xF2, IO_INDEX_PORT);
142 outb_p(0xFF, IO_DATA_PORT);
143 outb_p(0xF3, IO_INDEX_PORT);
144 outb_p(0x00, IO_DATA_PORT);
145 outb_p(0xF4, IO_INDEX_PORT);
146 outb_p(0x00, IO_DATA_PORT);
147 outb_p(0xF2, IO_INDEX_PORT);
148 outb_p(0x00, IO_DATA_PORT);
150 /* at last select device Aux1 (dev=7) and set GP16 as a watchdog output */
151 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
152 outb_p(0x07, IO_DATA_PORT);
153 outb_p(0xE6, IO_INDEX_PORT);
154 outb_p(0x08, IO_DATA_PORT);
156 /* lock the SuperIO chip */
157 outb_p(LOCK_DATA, IO_INDEX_PORT);
159 spin_unlock_irqrestore(&spinlock, flags);
160 printk(KERN_INFO PFX "shutdown.\n");
166 * Send a keepalive ping to the watchdog
167 * This is done by simply re-writing the timeout to reg. 0xF2
170 static int wdt977_keepalive(void)
173 spin_lock_irqsave(&spinlock, flags);
175 /* unlock the SuperIO chip */
176 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
177 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
179 /* select device Aux2 (device=8) and kicks watchdog reg F2 */
180 /* F2 has the timeout in minutes */
181 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
182 outb_p(0x08, IO_DATA_PORT);
183 outb_p(0xF2, IO_INDEX_PORT);
184 outb_p(timeoutM, IO_DATA_PORT);
186 /* lock the SuperIO chip */
187 outb_p(LOCK_DATA, IO_INDEX_PORT);
188 spin_unlock_irqrestore(&spinlock, flags);
194 * Set the watchdog timeout value
197 static int wdt977_set_timeout(int t)
201 /* convert seconds to minutes, rounding up */
202 tmrval = (t + 59) / 60;
204 if (machine_is_netwinder()) {
205 /* we have a hw bug somewhere, so each 977 minute is actually only 30sec
206 * this limits the max timeout to half of device max of 255 minutes...
211 if ((tmrval < 1) || (tmrval > 255))
214 /* timeout is the timeout in seconds, timeoutM is the timeout in minutes) */
221 * Get the watchdog status
224 static int wdt977_get_status(int *status)
229 spin_lock_irqsave(&spinlock, flags);
231 /* unlock the SuperIO chip */
232 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
233 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
235 /* select device Aux2 (device=8) and read watchdog reg F4 */
236 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
237 outb_p(0x08, IO_DATA_PORT);
238 outb_p(0xF4, IO_INDEX_PORT);
239 new_status = inb_p(IO_DATA_PORT);
241 /* lock the SuperIO chip */
242 outb_p(LOCK_DATA, IO_INDEX_PORT);
244 spin_unlock_irqrestore(&spinlock, flags);
248 *status |= WDIOF_CARDRESET;
255 * /dev/watchdog handling
258 static int wdt977_open(struct inode *inode, struct file *file)
260 /* If the watchdog is alive we don't need to start it again */
261 if( test_and_set_bit(0,&timer_alive) )
265 __module_get(THIS_MODULE);
268 return nonseekable_open(inode, file);
271 static int wdt977_release(struct inode *inode, struct file *file)
274 * Shut off the timer.
275 * Lock it in if it's a module and we set nowayout
277 if (expect_close == 42)
280 clear_bit(0,&timer_alive);
283 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
292 * @file: file handle to the watchdog
293 * @buf: buffer to write (unused as data does not matter here
294 * @count: count of bytes
295 * @ppos: pointer to the position to write. No seeks allowed
297 * A write to a watchdog device is defined as a keepalive signal. Any
298 * write of data will do, as we we don't define content meaning.
301 static ssize_t wdt977_write(struct file *file, const char __user *buf,
302 size_t count, loff_t *ppos)
310 /* In case it was set long ago */
313 for (i = 0; i != count; i++)
316 if (get_user(c, buf + i))
323 /* someone wrote to us, we should restart timer */
331 * @inode: inode of the device
332 * @file: file handle to the device
333 * @cmd: watchdog command
334 * @arg: argument pointer
336 * The watchdog API defines a common set of functions for all watchdogs
337 * according to their available features.
340 static struct watchdog_info ident = {
341 .options = WDIOF_SETTIMEOUT |
344 .firmware_version = 1,
345 .identity = WATCHDOG_NAME,
348 static int wdt977_ioctl(struct inode *inode, struct file *file,
349 unsigned int cmd, unsigned long arg)
352 int new_options, retval = -EINVAL;
355 struct watchdog_info __user *ident;
359 uarg.i = (int __user *)arg;
366 case WDIOC_GETSUPPORT:
367 return copy_to_user(uarg.ident, &ident,
368 sizeof(ident)) ? -EFAULT : 0;
370 case WDIOC_GETSTATUS:
371 wdt977_get_status(&status);
372 return put_user(status, uarg.i);
374 case WDIOC_GETBOOTSTATUS:
375 return put_user(0, uarg.i);
377 case WDIOC_KEEPALIVE:
381 case WDIOC_SETOPTIONS:
382 if (get_user (new_options, uarg.i))
385 if (new_options & WDIOS_DISABLECARD) {
390 if (new_options & WDIOS_ENABLECARD) {
397 case WDIOC_SETTIMEOUT:
398 if (get_user(new_timeout, uarg.i))
401 if (wdt977_set_timeout(new_timeout))
407 case WDIOC_GETTIMEOUT:
408 return put_user(timeout, uarg.i);
413 static int wdt977_notify_sys(struct notifier_block *this, unsigned long code,
416 if(code==SYS_DOWN || code==SYS_HALT)
421 static const struct file_operations wdt977_fops=
423 .owner = THIS_MODULE,
425 .write = wdt977_write,
426 .ioctl = wdt977_ioctl,
428 .release = wdt977_release,
431 static struct miscdevice wdt977_miscdev=
433 .minor = WATCHDOG_MINOR,
435 .fops = &wdt977_fops,
438 static struct notifier_block wdt977_notifier = {
439 .notifier_call = wdt977_notify_sys,
442 static int __init wd977_init(void)
446 //if (!machine_is_netwinder())
449 printk(KERN_INFO PFX DRIVER_VERSION);
451 spin_lock_init(&spinlock);
453 /* Check that the timeout value is within it's range ; if not reset to the default */
454 if (wdt977_set_timeout(timeout))
456 wdt977_set_timeout(DEFAULT_TIMEOUT);
457 printk(KERN_INFO PFX "timeout value must be 60<timeout<15300, using %d\n",
461 /* on Netwinder the IOports are already reserved by
462 * arch/arm/mach-footbridge/netwinder-hw.c
464 if (!machine_is_netwinder())
466 if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME))
468 printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
475 rc = misc_register(&wdt977_miscdev);
478 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
479 wdt977_miscdev.minor, rc);
483 rc = register_reboot_notifier(&wdt977_notifier);
486 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
488 goto err_out_miscdev;
491 printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d, testmode=%i)\n",
492 timeout, nowayout, testmode);
497 misc_deregister(&wdt977_miscdev);
499 if (!machine_is_netwinder())
500 release_region(IO_INDEX_PORT,2);
505 static void __exit wd977_exit(void)
508 misc_deregister(&wdt977_miscdev);
509 unregister_reboot_notifier(&wdt977_notifier);
510 release_region(IO_INDEX_PORT,2);
513 module_init(wd977_init);
514 module_exit(wd977_exit);
516 MODULE_AUTHOR("Woody Suwalski <woodys@xandros.com>");
517 MODULE_DESCRIPTION("W83977AF Watchdog driver");
518 MODULE_LICENSE("GPL");
519 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);