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Diffstat (limited to 'drivers/watchdog/wdt977.c')
-rw-r--r--drivers/watchdog/wdt977.c519
1 files changed, 519 insertions, 0 deletions
diff --git a/drivers/watchdog/wdt977.c b/drivers/watchdog/wdt977.c
new file mode 100644
index 000000000000..7d300ff7ab07
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+++ b/drivers/watchdog/wdt977.c
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1/*
2 * Wdt977 0.04: A Watchdog Device for Netwinder W83977AF chip
3 *
4 * (c) Copyright 1998 Rebel.com (Woody Suwalski <woody@netwinder.org>)
5 *
6 * -----------------------
7 *
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.
12 *
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
20 * nwwatchdog_init.
21 * 25-Oct-2005 Woody Suwalski: Convert addresses to #defs, add spinlocks
22 * remove limitiation to be used on Netwinders only
23 */
24
25#include <linux/module.h>
26#include <linux/moduleparam.h>
27#include <linux/types.h>
28#include <linux/kernel.h>
29#include <linux/fs.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>
36
37#include <asm/io.h>
38#include <asm/system.h>
39#include <asm/mach-types.h>
40#include <asm/uaccess.h>
41
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"
46
47#define IO_INDEX_PORT 0x370 /* on some systems it can be 0x3F0 */
48#define IO_DATA_PORT (IO_INDEX_PORT+1)
49
50#define UNLOCK_DATA 0x87
51#define LOCK_DATA 0xAA
52#define DEVICE_REGISTER 0x07
53
54
55#define DEFAULT_TIMEOUT 60 /* default timeout in seconds */
56
57static int timeout = DEFAULT_TIMEOUT;
58static int timeoutM; /* timeout in minutes */
59static unsigned long timer_alive;
60static int testmode;
61static char expect_close;
62static spinlock_t spinlock;
63
64module_param(timeout, int, 0);
65MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (60..15300), default=" __MODULE_STRING(DEFAULT_TIMEOUT) ")");
66module_param(testmode, int, 0);
67MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0");
68
69static int nowayout = WATCHDOG_NOWAYOUT;
70module_param(nowayout, int, 0);
71MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
72
73/*
74 * Start the watchdog
75 */
76
77static int wdt977_start(void)
78{
79 unsigned long flags;
80
81 spin_lock_irqsave(&spinlock, flags);
82
83 /* unlock the SuperIO chip */
84 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
85 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
86
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)
92 */
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);
101
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" */
104 if (!testmode)
105 {
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);
110 }
111
112 /* lock the SuperIO chip */
113 outb_p(LOCK_DATA, IO_INDEX_PORT);
114
115 spin_unlock_irqrestore(&spinlock, flags);
116 printk(KERN_INFO PFX "activated.\n");
117
118 return 0;
119}
120
121/*
122 * Stop the watchdog
123 */
124
125static int wdt977_stop(void)
126{
127 unsigned long flags;
128 spin_lock_irqsave(&spinlock, flags);
129
130 /* unlock the SuperIO chip */
131 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
132 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
133
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
138 */
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);
149
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);
155
156 /* lock the SuperIO chip */
157 outb_p(LOCK_DATA, IO_INDEX_PORT);
158
159 spin_unlock_irqrestore(&spinlock, flags);
160 printk(KERN_INFO PFX "shutdown.\n");
161
162 return 0;
163}
164
165/*
166 * Send a keepalive ping to the watchdog
167 * This is done by simply re-writing the timeout to reg. 0xF2
168 */
169
170static int wdt977_keepalive(void)
171{
172 unsigned long flags;
173 spin_lock_irqsave(&spinlock, flags);
174
175 /* unlock the SuperIO chip */
176 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
177 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
178
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);
185
186 /* lock the SuperIO chip */
187 outb_p(LOCK_DATA, IO_INDEX_PORT);
188 spin_unlock_irqrestore(&spinlock, flags);
189
190 return 0;
191}
192
193/*
194 * Set the watchdog timeout value
195 */
196
197static int wdt977_set_timeout(int t)
198{
199 int tmrval;
200
201 /* convert seconds to minutes, rounding up */
202 tmrval = (t + 59) / 60;
203
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...
207 */
208 tmrval += tmrval;
209 }
210
211 if ((tmrval < 1) || (tmrval > 255))
212 return -EINVAL;
213
214 /* timeout is the timeout in seconds, timeoutM is the timeout in minutes) */
215 timeout = t;
216 timeoutM = tmrval;
217 return 0;
218}
219
220/*
221 * Get the watchdog status
222 */
223
224static int wdt977_get_status(int *status)
225{
226 int new_status;
227 unsigned long flags;
228
229 spin_lock_irqsave(&spinlock, flags);
230
231 /* unlock the SuperIO chip */
232 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
233 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
234
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);
240
241 /* lock the SuperIO chip */
242 outb_p(LOCK_DATA, IO_INDEX_PORT);
243
244 spin_unlock_irqrestore(&spinlock, flags);
245
246 *status=0;
247 if (new_status & 1)
248 *status |= WDIOF_CARDRESET;
249
250 return 0;
251}
252
253
254/*
255 * /dev/watchdog handling
256 */
257
258static int wdt977_open(struct inode *inode, struct file *file)
259{
260 /* If the watchdog is alive we don't need to start it again */
261 if( test_and_set_bit(0,&timer_alive) )
262 return -EBUSY;
263
264 if (nowayout)
265 __module_get(THIS_MODULE);
266
267 wdt977_start();
268 return nonseekable_open(inode, file);
269}
270
271static int wdt977_release(struct inode *inode, struct file *file)
272{
273 /*
274 * Shut off the timer.
275 * Lock it in if it's a module and we set nowayout
276 */
277 if (expect_close == 42)
278 {
279 wdt977_stop();
280 clear_bit(0,&timer_alive);
281 } else {
282 wdt977_keepalive();
283 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
284 }
285 expect_close = 0;
286 return 0;
287}
288
289
290/*
291 * wdt977_write:
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
296 *
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.
299 */
300
301static ssize_t wdt977_write(struct file *file, const char __user *buf,
302 size_t count, loff_t *ppos)
303{
304 if (count)
305 {
306 if (!nowayout)
307 {
308 size_t i;
309
310 /* In case it was set long ago */
311 expect_close = 0;
312
313 for (i = 0; i != count; i++)
314 {
315 char c;
316 if (get_user(c, buf + i))
317 return -EFAULT;
318 if (c == 'V')
319 expect_close = 42;
320 }
321 }
322
323 /* someone wrote to us, we should restart timer */
324 wdt977_keepalive();
325 }
326 return count;
327}
328
329/*
330 * wdt977_ioctl:
331 * @inode: inode of the device
332 * @file: file handle to the device
333 * @cmd: watchdog command
334 * @arg: argument pointer
335 *
336 * The watchdog API defines a common set of functions for all watchdogs
337 * according to their available features.
338 */
339
340static struct watchdog_info ident = {
341 .options = WDIOF_SETTIMEOUT |
342 WDIOF_MAGICCLOSE |
343 WDIOF_KEEPALIVEPING,
344 .firmware_version = 1,
345 .identity = WATCHDOG_NAME,
346};
347
348static int wdt977_ioctl(struct inode *inode, struct file *file,
349 unsigned int cmd, unsigned long arg)
350{
351 int status;
352 int new_options, retval = -EINVAL;
353 int new_timeout;
354 union {
355 struct watchdog_info __user *ident;
356 int __user *i;
357 } uarg;
358
359 uarg.i = (int __user *)arg;
360
361 switch(cmd)
362 {
363 default:
364 return -ENOTTY;
365
366 case WDIOC_GETSUPPORT:
367 return copy_to_user(uarg.ident, &ident,
368 sizeof(ident)) ? -EFAULT : 0;
369
370 case WDIOC_GETSTATUS:
371 wdt977_get_status(&status);
372 return put_user(status, uarg.i);
373
374 case WDIOC_GETBOOTSTATUS:
375 return put_user(0, uarg.i);
376
377 case WDIOC_KEEPALIVE:
378 wdt977_keepalive();
379 return 0;
380
381 case WDIOC_SETOPTIONS:
382 if (get_user (new_options, uarg.i))
383 return -EFAULT;
384
385 if (new_options & WDIOS_DISABLECARD) {
386 wdt977_stop();
387 retval = 0;
388 }
389
390 if (new_options & WDIOS_ENABLECARD) {
391 wdt977_start();
392 retval = 0;
393 }
394
395 return retval;
396
397 case WDIOC_SETTIMEOUT:
398 if (get_user(new_timeout, uarg.i))
399 return -EFAULT;
400
401 if (wdt977_set_timeout(new_timeout))
402 return -EINVAL;
403
404 wdt977_keepalive();
405 /* Fall */
406
407 case WDIOC_GETTIMEOUT:
408 return put_user(timeout, uarg.i);
409
410 }
411}
412
413static int wdt977_notify_sys(struct notifier_block *this, unsigned long code,
414 void *unused)
415{
416 if(code==SYS_DOWN || code==SYS_HALT)
417 wdt977_stop();
418 return NOTIFY_DONE;
419}
420
421static const struct file_operations wdt977_fops=
422{
423 .owner = THIS_MODULE,
424 .llseek = no_llseek,
425 .write = wdt977_write,
426 .ioctl = wdt977_ioctl,
427 .open = wdt977_open,
428 .release = wdt977_release,
429};
430
431static struct miscdevice wdt977_miscdev=
432{
433 .minor = WATCHDOG_MINOR,
434 .name = "watchdog",
435 .fops = &wdt977_fops,
436};
437
438static struct notifier_block wdt977_notifier = {
439 .notifier_call = wdt977_notify_sys,
440};
441
442static int __init wd977_init(void)
443{
444 int rc;
445
446 //if (!machine_is_netwinder())
447 // return -ENODEV;
448
449 printk(KERN_INFO PFX DRIVER_VERSION);
450
451 spin_lock_init(&spinlock);
452
453 /* Check that the timeout value is within it's range ; if not reset to the default */
454 if (wdt977_set_timeout(timeout))
455 {
456 wdt977_set_timeout(DEFAULT_TIMEOUT);
457 printk(KERN_INFO PFX "timeout value must be 60<timeout<15300, using %d\n",
458 DEFAULT_TIMEOUT);
459 }
460
461 /* on Netwinder the IOports are already reserved by
462 * arch/arm/mach-footbridge/netwinder-hw.c
463 */
464 if (!machine_is_netwinder())
465 {
466 if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME))
467 {
468 printk(KERN_ERR PFX "I/O address 0x%04x already in use\n",
469 IO_INDEX_PORT);
470 rc = -EIO;
471 goto err_out;
472 }
473 }
474
475 rc = misc_register(&wdt977_miscdev);
476 if (rc)
477 {
478 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
479 wdt977_miscdev.minor, rc);
480 goto err_out_region;
481 }
482
483 rc = register_reboot_notifier(&wdt977_notifier);
484 if (rc)
485 {
486 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
487 rc);
488 goto err_out_miscdev;
489 }
490
491 printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d, testmode=%i)\n",
492 timeout, nowayout, testmode);
493
494 return 0;
495
496err_out_miscdev:
497 misc_deregister(&wdt977_miscdev);
498err_out_region:
499 if (!machine_is_netwinder())
500 release_region(IO_INDEX_PORT,2);
501err_out:
502 return rc;
503}
504
505static void __exit wd977_exit(void)
506{
507 wdt977_stop();
508 misc_deregister(&wdt977_miscdev);
509 unregister_reboot_notifier(&wdt977_notifier);
510 release_region(IO_INDEX_PORT,2);
511}
512
513module_init(wd977_init);
514module_exit(wd977_exit);
515
516MODULE_AUTHOR("Woody Suwalski <woodys@xandros.com>");
517MODULE_DESCRIPTION("W83977AF Watchdog driver");
518MODULE_LICENSE("GPL");
519MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);