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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
23 * Netwinders only
24 */
25
26#include <linux/module.h>
27#include <linux/moduleparam.h>
28#include <linux/types.h>
29#include <linux/kernel.h>
30#include <linux/fs.h>
31#include <linux/miscdevice.h>
32#include <linux/init.h>
33#include <linux/ioport.h>
34#include <linux/watchdog.h>
35#include <linux/notifier.h>
36#include <linux/reboot.h>
37#include <linux/io.h>
38#include <linux/uaccess.h>
39
40#include <asm/system.h>
41#include <asm/mach-types.h>
42
43#define WATCHDOG_VERSION "0.04"
44#define WATCHDOG_NAME "Wdt977"
45#define PFX WATCHDOG_NAME ": "
46#define DRIVER_VERSION WATCHDOG_NAME " driver, v" WATCHDOG_VERSION "\n"
47
48#define IO_INDEX_PORT 0x370 /* on some systems it can be 0x3F0 */
49#define IO_DATA_PORT (IO_INDEX_PORT + 1)
50
51#define UNLOCK_DATA 0x87
52#define LOCK_DATA 0xAA
53#define DEVICE_REGISTER 0x07
54
55
56#define DEFAULT_TIMEOUT 60 /* default timeout in seconds */
57
58static int timeout = DEFAULT_TIMEOUT;
59static int timeoutM; /* timeout in minutes */
60static unsigned long timer_alive;
61static int testmode;
62static char expect_close;
63static DEFINE_SPINLOCK(spinlock);
64
65module_param(timeout, int, 0);
66MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (60..15300, default="
67 __MODULE_STRING(DEFAULT_TIMEOUT) ")");
68module_param(testmode, int, 0);
69MODULE_PARM_DESC(testmode, "Watchdog testmode (1 = no reboot), default=0");
70
71static int nowayout = WATCHDOG_NOWAYOUT;
72module_param(nowayout, int, 0);
73MODULE_PARM_DESC(nowayout,
74 "Watchdog cannot be stopped once started (default="
75 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
76
77/*
78 * Start the watchdog
79 */
80
81static int wdt977_start(void)
82{
83 unsigned long flags;
84
85 spin_lock_irqsave(&spinlock, flags);
86
87 /* unlock the SuperIO chip */
88 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
89 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
90
91 /* select device Aux2 (device=8) and set watchdog regs F2, F3 and F4
92 * F2 has the timeout in minutes
93 * F3 could be set to the POWER LED blink (with GP17 set to PowerLed)
94 * at timeout, and to reset timer on kbd/mouse activity (not impl.)
95 * F4 is used to just clear the TIMEOUT'ed state (bit 0)
96 */
97 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
98 outb_p(0x08, IO_DATA_PORT);
99 outb_p(0xF2, IO_INDEX_PORT);
100 outb_p(timeoutM, IO_DATA_PORT);
101 outb_p(0xF3, IO_INDEX_PORT);
102 outb_p(0x00, IO_DATA_PORT); /* another setting is 0E for
103 kbd/mouse/LED */
104 outb_p(0xF4, IO_INDEX_PORT);
105 outb_p(0x00, IO_DATA_PORT);
106
107 /* At last select device Aux1 (dev=7) and set GP16 as a
108 * watchdog output. In test mode watch the bit 1 on F4 to
109 * indicate "triggered"
110 */
111 if (!testmode) {
112 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
113 outb_p(0x07, IO_DATA_PORT);
114 outb_p(0xE6, IO_INDEX_PORT);
115 outb_p(0x08, IO_DATA_PORT);
116 }
117
118 /* lock the SuperIO chip */
119 outb_p(LOCK_DATA, IO_INDEX_PORT);
120
121 spin_unlock_irqrestore(&spinlock, flags);
122 printk(KERN_INFO PFX "activated.\n");
123
124 return 0;
125}
126
127/*
128 * Stop the watchdog
129 */
130
131static int wdt977_stop(void)
132{
133 unsigned long flags;
134 spin_lock_irqsave(&spinlock, flags);
135
136 /* unlock the SuperIO chip */
137 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
138 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
139
140 /* select device Aux2 (device=8) and set watchdog regs F2,F3 and F4
141 * F3 is reset to its default state
142 * F4 can clear the TIMEOUT'ed state (bit 0) - back to default
143 * We can not use GP17 as a PowerLed, as we use its usage as a RedLed
144 */
145 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
146 outb_p(0x08, IO_DATA_PORT);
147 outb_p(0xF2, IO_INDEX_PORT);
148 outb_p(0xFF, IO_DATA_PORT);
149 outb_p(0xF3, IO_INDEX_PORT);
150 outb_p(0x00, IO_DATA_PORT);
151 outb_p(0xF4, IO_INDEX_PORT);
152 outb_p(0x00, IO_DATA_PORT);
153 outb_p(0xF2, IO_INDEX_PORT);
154 outb_p(0x00, IO_DATA_PORT);
155
156 /* at last select device Aux1 (dev=7) and set
157 GP16 as a watchdog output */
158 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
159 outb_p(0x07, IO_DATA_PORT);
160 outb_p(0xE6, IO_INDEX_PORT);
161 outb_p(0x08, IO_DATA_PORT);
162
163 /* lock the SuperIO chip */
164 outb_p(LOCK_DATA, IO_INDEX_PORT);
165
166 spin_unlock_irqrestore(&spinlock, flags);
167 printk(KERN_INFO PFX "shutdown.\n");
168
169 return 0;
170}
171
172/*
173 * Send a keepalive ping to the watchdog
174 * This is done by simply re-writing the timeout to reg. 0xF2
175 */
176
177static int wdt977_keepalive(void)
178{
179 unsigned long flags;
180 spin_lock_irqsave(&spinlock, flags);
181
182 /* unlock the SuperIO chip */
183 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
184 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
185
186 /* select device Aux2 (device=8) and kicks watchdog reg F2 */
187 /* F2 has the timeout in minutes */
188 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
189 outb_p(0x08, IO_DATA_PORT);
190 outb_p(0xF2, IO_INDEX_PORT);
191 outb_p(timeoutM, IO_DATA_PORT);
192
193 /* lock the SuperIO chip */
194 outb_p(LOCK_DATA, IO_INDEX_PORT);
195 spin_unlock_irqrestore(&spinlock, flags);
196
197 return 0;
198}
199
200/*
201 * Set the watchdog timeout value
202 */
203
204static int wdt977_set_timeout(int t)
205{
206 int tmrval;
207
208 /* convert seconds to minutes, rounding up */
209 tmrval = (t + 59) / 60;
210
211 if (machine_is_netwinder()) {
212 /* we have a hw bug somewhere, so each 977 minute is actually
213 * only 30sec. This limits the max timeout to half of device
214 * max of 255 minutes...
215 */
216 tmrval += tmrval;
217 }
218
219 if (tmrval < 1 || tmrval > 255)
220 return -EINVAL;
221
222 /* timeout is the timeout in seconds, timeoutM is
223 the timeout in minutes) */
224 timeout = t;
225 timeoutM = tmrval;
226 return 0;
227}
228
229/*
230 * Get the watchdog status
231 */
232
233static int wdt977_get_status(int *status)
234{
235 int new_status;
236 unsigned long flags;
237
238 spin_lock_irqsave(&spinlock, flags);
239
240 /* unlock the SuperIO chip */
241 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
242 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
243
244 /* select device Aux2 (device=8) and read watchdog reg F4 */
245 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
246 outb_p(0x08, IO_DATA_PORT);
247 outb_p(0xF4, IO_INDEX_PORT);
248 new_status = inb_p(IO_DATA_PORT);
249
250 /* lock the SuperIO chip */
251 outb_p(LOCK_DATA, IO_INDEX_PORT);
252
253 spin_unlock_irqrestore(&spinlock, flags);
254
255 *status = 0;
256 if (new_status & 1)
257 *status |= WDIOF_CARDRESET;
258
259 return 0;
260}
261
262
263/*
264 * /dev/watchdog handling
265 */
266
267static int wdt977_open(struct inode *inode, struct file *file)
268{
269 /* If the watchdog is alive we don't need to start it again */
270 if (test_and_set_bit(0, &timer_alive))
271 return -EBUSY;
272
273 if (nowayout)
274 __module_get(THIS_MODULE);
275
276 wdt977_start();
277 return nonseekable_open(inode, file);
278}
279
280static int wdt977_release(struct inode *inode, struct file *file)
281{
282 /*
283 * Shut off the timer.
284 * Lock it in if it's a module and we set nowayout
285 */
286 if (expect_close == 42) {
287 wdt977_stop();
288 clear_bit(0, &timer_alive);
289 } else {
290 wdt977_keepalive();
291 printk(KERN_CRIT PFX
292 "Unexpected close, not stopping watchdog!\n");
293 }
294 expect_close = 0;
295 return 0;
296}
297
298
299/*
300 * wdt977_write:
301 * @file: file handle to the watchdog
302 * @buf: buffer to write (unused as data does not matter here
303 * @count: count of bytes
304 * @ppos: pointer to the position to write. No seeks allowed
305 *
306 * A write to a watchdog device is defined as a keepalive signal. Any
307 * write of data will do, as we we don't define content meaning.
308 */
309
310static ssize_t wdt977_write(struct file *file, const char __user *buf,
311 size_t count, loff_t *ppos)
312{
313 if (count) {
314 if (!nowayout) {
315 size_t i;
316
317 /* In case it was set long ago */
318 expect_close = 0;
319
320 for (i = 0; i != count; i++) {
321 char c;
322 if (get_user(c, buf + i))
323 return -EFAULT;
324 if (c == 'V')
325 expect_close = 42;
326 }
327 }
328
329 /* someone wrote to us, we should restart timer */
330 wdt977_keepalive();
331 }
332 return count;
333}
334
335static const struct watchdog_info ident = {
336 .options = WDIOF_SETTIMEOUT |
337 WDIOF_MAGICCLOSE |
338 WDIOF_KEEPALIVEPING,
339 .firmware_version = 1,
340 .identity = WATCHDOG_NAME,
341};
342
343/*
344 * wdt977_ioctl:
345 * @inode: inode of the device
346 * @file: file handle to the device
347 * @cmd: watchdog command
348 * @arg: argument pointer
349 *
350 * The watchdog API defines a common set of functions for all watchdogs
351 * according to their available features.
352 */
353
354static long wdt977_ioctl(struct file *file, unsigned int cmd,
355 unsigned long arg)
356{
357 int status;
358 int new_options, retval = -EINVAL;
359 int new_timeout;
360 union {
361 struct watchdog_info __user *ident;
362 int __user *i;
363 } uarg;
364
365 uarg.i = (int __user *)arg;
366
367 switch (cmd) {
368 case WDIOC_GETSUPPORT:
369 return copy_to_user(uarg.ident, &ident,
370 sizeof(ident)) ? -EFAULT : 0;
371
372 case WDIOC_GETSTATUS:
373 wdt977_get_status(&status);
374 return put_user(status, uarg.i);
375
376 case WDIOC_GETBOOTSTATUS:
377 return put_user(0, uarg.i);
378
379 case WDIOC_SETOPTIONS:
380 if (get_user(new_options, uarg.i))
381 return -EFAULT;
382
383 if (new_options & WDIOS_DISABLECARD) {
384 wdt977_stop();
385 retval = 0;
386 }
387
388 if (new_options & WDIOS_ENABLECARD) {
389 wdt977_start();
390 retval = 0;
391 }
392
393 return retval;
394
395 case WDIOC_KEEPALIVE:
396 wdt977_keepalive();
397 return 0;
398
399 case WDIOC_SETTIMEOUT:
400 if (get_user(new_timeout, uarg.i))
401 return -EFAULT;
402
403 if (wdt977_set_timeout(new_timeout))
404 return -EINVAL;
405
406 wdt977_keepalive();
407 /* Fall */
408
409 case WDIOC_GETTIMEOUT:
410 return put_user(timeout, uarg.i);
411
412 default:
413 return -ENOTTY;
414
415 }
416}
417
418static int wdt977_notify_sys(struct notifier_block *this, unsigned long code,
419 void *unused)
420{
421 if (code == SYS_DOWN || code == SYS_HALT)
422 wdt977_stop();
423 return NOTIFY_DONE;
424}
425
426static const struct file_operations wdt977_fops = {
427 .owner = THIS_MODULE,
428 .llseek = no_llseek,
429 .write = wdt977_write,
430 .unlocked_ioctl = wdt977_ioctl,
431 .open = wdt977_open,
432 .release = wdt977_release,
433};
434
435static struct miscdevice wdt977_miscdev = {
436 .minor = WATCHDOG_MINOR,
437 .name = "watchdog",
438 .fops = &wdt977_fops,
439};
440
441static struct notifier_block wdt977_notifier = {
442 .notifier_call = wdt977_notify_sys,
443};
444
445static int __init wd977_init(void)
446{
447 int rc;
448
449 printk(KERN_INFO PFX DRIVER_VERSION);
450
451 /* Check that the timeout value is within its range;
452 if not reset to the default */
453 if (wdt977_set_timeout(timeout)) {
454 wdt977_set_timeout(DEFAULT_TIMEOUT);
455 printk(KERN_INFO PFX
456 "timeout value must be 60 < timeout < 15300, using %d\n",
457 DEFAULT_TIMEOUT);
458 }
459
460 /* on Netwinder the IOports are already reserved by
461 * arch/arm/mach-footbridge/netwinder-hw.c
462 */
463 if (!machine_is_netwinder()) {
464 if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME)) {
465 printk(KERN_ERR PFX
466 "I/O address 0x%04x already in use\n",
467 IO_INDEX_PORT);
468 rc = -EIO;
469 goto err_out;
470 }
471 }
472
473 rc = register_reboot_notifier(&wdt977_notifier);
474 if (rc) {
475 printk(KERN_ERR PFX
476 "cannot register reboot notifier (err=%d)\n", rc);
477 goto err_out_region;
478 }
479
480 rc = misc_register(&wdt977_miscdev);
481 if (rc) {
482 printk(KERN_ERR PFX
483 "cannot register miscdev on minor=%d (err=%d)\n",
484 wdt977_miscdev.minor, rc);
485 goto err_out_reboot;
486 }
487
488 printk(KERN_INFO PFX
489 "initialized. timeout=%d sec (nowayout=%d, testmode=%i)\n",
490 timeout, nowayout, testmode);
491
492 return 0;
493
494err_out_reboot:
495 unregister_reboot_notifier(&wdt977_notifier);
496err_out_region:
497 if (!machine_is_netwinder())
498 release_region(IO_INDEX_PORT, 2);
499err_out:
500 return rc;
501}
502
503static void __exit wd977_exit(void)
504{
505 wdt977_stop();
506 misc_deregister(&wdt977_miscdev);
507 unregister_reboot_notifier(&wdt977_notifier);
508 release_region(IO_INDEX_PORT, 2);
509}
510
511module_init(wd977_init);
512module_exit(wd977_exit);
513
514MODULE_AUTHOR("Woody Suwalski <woodys@xandros.com>");
515MODULE_DESCRIPTION("W83977AF Watchdog driver");
516MODULE_LICENSE("GPL");
517MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
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
23 * Netwinders only
24 */
25
26#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
27
28#include <linux/module.h>
29#include <linux/moduleparam.h>
30#include <linux/types.h>
31#include <linux/kernel.h>
32#include <linux/fs.h>
33#include <linux/miscdevice.h>
34#include <linux/init.h>
35#include <linux/ioport.h>
36#include <linux/watchdog.h>
37#include <linux/notifier.h>
38#include <linux/reboot.h>
39#include <linux/io.h>
40#include <linux/uaccess.h>
41
42#include <asm/mach-types.h>
43
44#define WATCHDOG_VERSION "0.04"
45#define WATCHDOG_NAME "Wdt977"
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 DEFINE_SPINLOCK(spinlock);
63
64module_param(timeout, int, 0);
65MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds (60..15300, default="
66 __MODULE_STRING(DEFAULT_TIMEOUT) ")");
67module_param(testmode, int, 0);
68MODULE_PARM_DESC(testmode, "Watchdog testmode (1 = no reboot), default=0");
69
70static bool nowayout = WATCHDOG_NOWAYOUT;
71module_param(nowayout, bool, 0);
72MODULE_PARM_DESC(nowayout,
73 "Watchdog cannot be stopped once started (default="
74 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
75
76/*
77 * Start the watchdog
78 */
79
80static int wdt977_start(void)
81{
82 unsigned long flags;
83
84 spin_lock_irqsave(&spinlock, flags);
85
86 /* unlock the SuperIO chip */
87 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
88 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
89
90 /* select device Aux2 (device=8) and set watchdog regs F2, F3 and F4
91 * F2 has the timeout in minutes
92 * F3 could be set to the POWER LED blink (with GP17 set to PowerLed)
93 * at timeout, and to reset timer on kbd/mouse activity (not impl.)
94 * F4 is used to just clear the TIMEOUT'ed state (bit 0)
95 */
96 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
97 outb_p(0x08, IO_DATA_PORT);
98 outb_p(0xF2, IO_INDEX_PORT);
99 outb_p(timeoutM, IO_DATA_PORT);
100 outb_p(0xF3, IO_INDEX_PORT);
101 outb_p(0x00, IO_DATA_PORT); /* another setting is 0E for
102 kbd/mouse/LED */
103 outb_p(0xF4, IO_INDEX_PORT);
104 outb_p(0x00, IO_DATA_PORT);
105
106 /* At last select device Aux1 (dev=7) and set GP16 as a
107 * watchdog output. In test mode watch the bit 1 on F4 to
108 * indicate "triggered"
109 */
110 if (!testmode) {
111 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
112 outb_p(0x07, IO_DATA_PORT);
113 outb_p(0xE6, IO_INDEX_PORT);
114 outb_p(0x08, IO_DATA_PORT);
115 }
116
117 /* lock the SuperIO chip */
118 outb_p(LOCK_DATA, IO_INDEX_PORT);
119
120 spin_unlock_irqrestore(&spinlock, flags);
121 pr_info("activated\n");
122
123 return 0;
124}
125
126/*
127 * Stop the watchdog
128 */
129
130static int wdt977_stop(void)
131{
132 unsigned long flags;
133 spin_lock_irqsave(&spinlock, flags);
134
135 /* unlock the SuperIO chip */
136 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
137 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
138
139 /* select device Aux2 (device=8) and set watchdog regs F2,F3 and F4
140 * F3 is reset to its default state
141 * F4 can clear the TIMEOUT'ed state (bit 0) - back to default
142 * We can not use GP17 as a PowerLed, as we use its usage as a RedLed
143 */
144 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
145 outb_p(0x08, IO_DATA_PORT);
146 outb_p(0xF2, IO_INDEX_PORT);
147 outb_p(0xFF, IO_DATA_PORT);
148 outb_p(0xF3, IO_INDEX_PORT);
149 outb_p(0x00, IO_DATA_PORT);
150 outb_p(0xF4, IO_INDEX_PORT);
151 outb_p(0x00, IO_DATA_PORT);
152 outb_p(0xF2, IO_INDEX_PORT);
153 outb_p(0x00, IO_DATA_PORT);
154
155 /* at last select device Aux1 (dev=7) and set
156 GP16 as a watchdog output */
157 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
158 outb_p(0x07, IO_DATA_PORT);
159 outb_p(0xE6, IO_INDEX_PORT);
160 outb_p(0x08, IO_DATA_PORT);
161
162 /* lock the SuperIO chip */
163 outb_p(LOCK_DATA, IO_INDEX_PORT);
164
165 spin_unlock_irqrestore(&spinlock, flags);
166 pr_info("shutdown\n");
167
168 return 0;
169}
170
171/*
172 * Send a keepalive ping to the watchdog
173 * This is done by simply re-writing the timeout to reg. 0xF2
174 */
175
176static int wdt977_keepalive(void)
177{
178 unsigned long flags;
179 spin_lock_irqsave(&spinlock, flags);
180
181 /* unlock the SuperIO chip */
182 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
183 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
184
185 /* select device Aux2 (device=8) and kicks watchdog reg F2 */
186 /* F2 has the timeout in minutes */
187 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
188 outb_p(0x08, IO_DATA_PORT);
189 outb_p(0xF2, IO_INDEX_PORT);
190 outb_p(timeoutM, IO_DATA_PORT);
191
192 /* lock the SuperIO chip */
193 outb_p(LOCK_DATA, IO_INDEX_PORT);
194 spin_unlock_irqrestore(&spinlock, flags);
195
196 return 0;
197}
198
199/*
200 * Set the watchdog timeout value
201 */
202
203static int wdt977_set_timeout(int t)
204{
205 int tmrval;
206
207 /* convert seconds to minutes, rounding up */
208 tmrval = (t + 59) / 60;
209
210 if (machine_is_netwinder()) {
211 /* we have a hw bug somewhere, so each 977 minute is actually
212 * only 30sec. This limits the max timeout to half of device
213 * max of 255 minutes...
214 */
215 tmrval += tmrval;
216 }
217
218 if (tmrval < 1 || tmrval > 255)
219 return -EINVAL;
220
221 /* timeout is the timeout in seconds, timeoutM is
222 the timeout in minutes) */
223 timeout = t;
224 timeoutM = tmrval;
225 return 0;
226}
227
228/*
229 * Get the watchdog status
230 */
231
232static int wdt977_get_status(int *status)
233{
234 int new_status;
235 unsigned long flags;
236
237 spin_lock_irqsave(&spinlock, flags);
238
239 /* unlock the SuperIO chip */
240 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
241 outb_p(UNLOCK_DATA, IO_INDEX_PORT);
242
243 /* select device Aux2 (device=8) and read watchdog reg F4 */
244 outb_p(DEVICE_REGISTER, IO_INDEX_PORT);
245 outb_p(0x08, IO_DATA_PORT);
246 outb_p(0xF4, IO_INDEX_PORT);
247 new_status = inb_p(IO_DATA_PORT);
248
249 /* lock the SuperIO chip */
250 outb_p(LOCK_DATA, IO_INDEX_PORT);
251
252 spin_unlock_irqrestore(&spinlock, flags);
253
254 *status = 0;
255 if (new_status & 1)
256 *status |= WDIOF_CARDRESET;
257
258 return 0;
259}
260
261
262/*
263 * /dev/watchdog handling
264 */
265
266static int wdt977_open(struct inode *inode, struct file *file)
267{
268 /* If the watchdog is alive we don't need to start it again */
269 if (test_and_set_bit(0, &timer_alive))
270 return -EBUSY;
271
272 if (nowayout)
273 __module_get(THIS_MODULE);
274
275 wdt977_start();
276 return nonseekable_open(inode, file);
277}
278
279static int wdt977_release(struct inode *inode, struct file *file)
280{
281 /*
282 * Shut off the timer.
283 * Lock it in if it's a module and we set nowayout
284 */
285 if (expect_close == 42) {
286 wdt977_stop();
287 clear_bit(0, &timer_alive);
288 } else {
289 wdt977_keepalive();
290 pr_crit("Unexpected close, not stopping watchdog!\n");
291 }
292 expect_close = 0;
293 return 0;
294}
295
296
297/*
298 * wdt977_write:
299 * @file: file handle to the watchdog
300 * @buf: buffer to write (unused as data does not matter here
301 * @count: count of bytes
302 * @ppos: pointer to the position to write. No seeks allowed
303 *
304 * A write to a watchdog device is defined as a keepalive signal. Any
305 * write of data will do, as we we don't define content meaning.
306 */
307
308static ssize_t wdt977_write(struct file *file, const char __user *buf,
309 size_t count, loff_t *ppos)
310{
311 if (count) {
312 if (!nowayout) {
313 size_t i;
314
315 /* In case it was set long ago */
316 expect_close = 0;
317
318 for (i = 0; i != count; i++) {
319 char c;
320 if (get_user(c, buf + i))
321 return -EFAULT;
322 if (c == 'V')
323 expect_close = 42;
324 }
325 }
326
327 /* someone wrote to us, we should restart timer */
328 wdt977_keepalive();
329 }
330 return count;
331}
332
333static const struct watchdog_info ident = {
334 .options = WDIOF_SETTIMEOUT |
335 WDIOF_MAGICCLOSE |
336 WDIOF_KEEPALIVEPING,
337 .firmware_version = 1,
338 .identity = WATCHDOG_NAME,
339};
340
341/*
342 * wdt977_ioctl:
343 * @inode: inode of the device
344 * @file: file handle to the device
345 * @cmd: watchdog command
346 * @arg: argument pointer
347 *
348 * The watchdog API defines a common set of functions for all watchdogs
349 * according to their available features.
350 */
351
352static long wdt977_ioctl(struct file *file, unsigned int cmd,
353 unsigned long arg)
354{
355 int status;
356 int new_options, retval = -EINVAL;
357 int new_timeout;
358 union {
359 struct watchdog_info __user *ident;
360 int __user *i;
361 } uarg;
362
363 uarg.i = (int __user *)arg;
364
365 switch (cmd) {
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_SETOPTIONS:
378 if (get_user(new_options, uarg.i))
379 return -EFAULT;
380
381 if (new_options & WDIOS_DISABLECARD) {
382 wdt977_stop();
383 retval = 0;
384 }
385
386 if (new_options & WDIOS_ENABLECARD) {
387 wdt977_start();
388 retval = 0;
389 }
390
391 return retval;
392
393 case WDIOC_KEEPALIVE:
394 wdt977_keepalive();
395 return 0;
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 default:
411 return -ENOTTY;
412
413 }
414}
415
416static int wdt977_notify_sys(struct notifier_block *this, unsigned long code,
417 void *unused)
418{
419 if (code == SYS_DOWN || code == SYS_HALT)
420 wdt977_stop();
421 return NOTIFY_DONE;
422}
423
424static const struct file_operations wdt977_fops = {
425 .owner = THIS_MODULE,
426 .llseek = no_llseek,
427 .write = wdt977_write,
428 .unlocked_ioctl = wdt977_ioctl,
429 .open = wdt977_open,
430 .release = wdt977_release,
431};
432
433static struct miscdevice wdt977_miscdev = {
434 .minor = WATCHDOG_MINOR,
435 .name = "watchdog",
436 .fops = &wdt977_fops,
437};
438
439static struct notifier_block wdt977_notifier = {
440 .notifier_call = wdt977_notify_sys,
441};
442
443static int __init wd977_init(void)
444{
445 int rc;
446
447 pr_info("driver v%s\n", WATCHDOG_VERSION);
448
449 /* Check that the timeout value is within its range;
450 if not reset to the default */
451 if (wdt977_set_timeout(timeout)) {
452 wdt977_set_timeout(DEFAULT_TIMEOUT);
453 pr_info("timeout value must be 60 < timeout < 15300, using %d\n",
454 DEFAULT_TIMEOUT);
455 }
456
457 /* on Netwinder the IOports are already reserved by
458 * arch/arm/mach-footbridge/netwinder-hw.c
459 */
460 if (!machine_is_netwinder()) {
461 if (!request_region(IO_INDEX_PORT, 2, WATCHDOG_NAME)) {
462 pr_err("I/O address 0x%04x already in use\n",
463 IO_INDEX_PORT);
464 rc = -EIO;
465 goto err_out;
466 }
467 }
468
469 rc = register_reboot_notifier(&wdt977_notifier);
470 if (rc) {
471 pr_err("cannot register reboot notifier (err=%d)\n", rc);
472 goto err_out_region;
473 }
474
475 rc = misc_register(&wdt977_miscdev);
476 if (rc) {
477 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
478 wdt977_miscdev.minor, rc);
479 goto err_out_reboot;
480 }
481
482 pr_info("initialized. timeout=%d sec (nowayout=%d, testmode=%i)\n",
483 timeout, nowayout, testmode);
484
485 return 0;
486
487err_out_reboot:
488 unregister_reboot_notifier(&wdt977_notifier);
489err_out_region:
490 if (!machine_is_netwinder())
491 release_region(IO_INDEX_PORT, 2);
492err_out:
493 return rc;
494}
495
496static void __exit wd977_exit(void)
497{
498 wdt977_stop();
499 misc_deregister(&wdt977_miscdev);
500 unregister_reboot_notifier(&wdt977_notifier);
501 release_region(IO_INDEX_PORT, 2);
502}
503
504module_init(wd977_init);
505module_exit(wd977_exit);
506
507MODULE_AUTHOR("Woody Suwalski <woodys@xandros.com>");
508MODULE_DESCRIPTION("W83977AF Watchdog driver");
509MODULE_LICENSE("GPL");
510MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);