blob: a5110f93a7551f0fdb541c634ed2010b6c2ac6f3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Advantech Single Board Computer WDT driver
3 *
4 * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
5 *
6 * Based on acquirewdt.c which is based on wdt.c.
7 * Original copyright messages:
8 *
9 * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved.
10 * http://www.redhat.com
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
16 *
17 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
18 * warranty for any of this software. This material is provided
19 * "AS-IS" and at no charge.
20 *
21 * (c) Copyright 1995 Alan Cox <alan@redhat.com>
22 *
23 * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com>
24 * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT
25 *
26 * 16-Oct-2002 Rob Radez <rob@osinvestor.com>
27 * Clean up ioctls, clean up init + exit, add expect close support,
28 * add wdt_start and wdt_stop as parameters.
29 */
30
31#include <linux/module.h>
32#include <linux/moduleparam.h>
33#include <linux/types.h>
34#include <linux/miscdevice.h>
35#include <linux/watchdog.h>
36#include <linux/fs.h>
37#include <linux/ioport.h>
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +010038#include <linux/platform_device.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039#include <linux/init.h>
Wim Van Sebroeck089ab072008-07-15 11:46:11 +000040#include <linux/io.h>
41#include <linux/uaccess.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070042
Linus Torvalds1da177e2005-04-16 15:20:36 -070043#include <asm/system.h>
44
Wim Van Sebroeck1d747be2007-01-11 22:19:28 +010045#define DRV_NAME "advantechwdt"
46#define PFX DRV_NAME ": "
Linus Torvalds1da177e2005-04-16 15:20:36 -070047#define WATCHDOG_NAME "Advantech WDT"
Linus Torvalds1da177e2005-04-16 15:20:36 -070048#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
49
Wim Van Sebroeck7944d3a2008-08-06 20:19:41 +000050/* the watchdog platform device */
51static struct platform_device *advwdt_platform_device;
Linus Torvalds1da177e2005-04-16 15:20:36 -070052static unsigned long advwdt_is_open;
53static char adv_expect_close;
54
55/*
56 * You must set these - there is no sane way to probe for this board.
57 *
58 * To enable or restart, write the timeout value in seconds (1 to 63)
59 * to I/O port wdt_start. To disable, read I/O port wdt_stop.
60 * Both are 0x443 for most boards (tested on a PCA-6276VE-00B1), but
61 * check your manual (at least the PCA-6159 seems to be different -
62 * the manual says wdt_stop is 0x43, not 0x443).
63 * (0x43 is also a write-only control register for the 8254 timer!)
64 */
65
66static int wdt_stop = 0x443;
67module_param(wdt_stop, int, 0);
68MODULE_PARM_DESC(wdt_stop, "Advantech WDT 'stop' io port (default 0x443)");
69
70static int wdt_start = 0x443;
71module_param(wdt_start, int, 0);
72MODULE_PARM_DESC(wdt_start, "Advantech WDT 'start' io port (default 0x443)");
73
74static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
75module_param(timeout, int, 0);
Alan Coxb6b4d9b2008-05-19 14:04:51 +010076MODULE_PARM_DESC(timeout,
77 "Watchdog timeout in seconds. 1<= timeout <=63, default="
78 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Andrey Panin4bfdf372005-07-27 11:43:58 -070080static int nowayout = WATCHDOG_NOWAYOUT;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081module_param(nowayout, int, 0);
Alan Coxb6b4d9b2008-05-19 14:04:51 +010082MODULE_PARM_DESC(nowayout,
83 "Watchdog cannot be stopped once started (default="
84 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
Linus Torvalds1da177e2005-04-16 15:20:36 -070085
86/*
Wim Van Sebroeck1d747be2007-01-11 22:19:28 +010087 * Watchdog Operations
Linus Torvalds1da177e2005-04-16 15:20:36 -070088 */
89
Alan Coxb6b4d9b2008-05-19 14:04:51 +010090static void advwdt_ping(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -070091{
92 /* Write a watchdog value */
93 outb_p(timeout, wdt_start);
94}
95
Alan Coxb6b4d9b2008-05-19 14:04:51 +010096static void advwdt_disable(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -070097{
98 inb_p(wdt_stop);
99}
100
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100101static int advwdt_set_heartbeat(int t)
Wim Van Sebroeck0349a362007-01-11 22:27:51 +0100102{
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100103 if (t < 1 || t > 63)
Wim Van Sebroeck0349a362007-01-11 22:27:51 +0100104 return -EINVAL;
Wim Van Sebroeck0349a362007-01-11 22:27:51 +0100105 timeout = t;
106 return 0;
107}
108
Wim Van Sebroeck1d747be2007-01-11 22:19:28 +0100109/*
110 * /dev/watchdog handling
111 */
112
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100113static ssize_t advwdt_write(struct file *file, const char __user *buf,
114 size_t count, loff_t *ppos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115{
116 if (count) {
117 if (!nowayout) {
118 size_t i;
119
120 adv_expect_close = 0;
121
122 for (i = 0; i != count; i++) {
123 char c;
Wim Van Sebroeck7944d3a2008-08-06 20:19:41 +0000124 if (get_user(c, buf + i))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 return -EFAULT;
126 if (c == 'V')
127 adv_expect_close = 42;
128 }
129 }
130 advwdt_ping();
131 }
132 return count;
133}
134
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100135static long advwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136{
137 int new_timeout;
138 void __user *argp = (void __user *)arg;
139 int __user *p = argp;
140 static struct watchdog_info ident = {
141 .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
142 .firmware_version = 1,
Wim Van Sebroeck1d747be2007-01-11 22:19:28 +0100143 .identity = WATCHDOG_NAME,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 };
145
146 switch (cmd) {
147 case WDIOC_GETSUPPORT:
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100148 if (copy_to_user(argp, &ident, sizeof(ident)))
149 return -EFAULT;
150 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151
152 case WDIOC_GETSTATUS:
153 case WDIOC_GETBOOTSTATUS:
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100154 return put_user(0, p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700155
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 case WDIOC_SETOPTIONS:
157 {
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100158 int options, retval = -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700159
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100160 if (get_user(options, p))
161 return -EFAULT;
162 if (options & WDIOS_DISABLECARD) {
163 advwdt_disable();
164 retval = 0;
165 }
166 if (options & WDIOS_ENABLECARD) {
167 advwdt_ping();
168 retval = 0;
169 }
170 return retval;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700171 }
Wim Van Sebroeck0c060902008-07-18 11:41:17 +0000172 case WDIOC_KEEPALIVE:
173 advwdt_ping();
174 break;
175
176 case WDIOC_SETTIMEOUT:
177 if (get_user(new_timeout, p))
178 return -EFAULT;
179 if (advwdt_set_heartbeat(new_timeout))
180 return -EINVAL;
181 advwdt_ping();
182 /* Fall */
183 case WDIOC_GETTIMEOUT:
184 return put_user(timeout, p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 default:
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100186 return -ENOTTY;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700187 }
188 return 0;
189}
190
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100191static int advwdt_open(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192{
193 if (test_and_set_bit(0, &advwdt_is_open))
194 return -EBUSY;
195 /*
196 * Activate
197 */
198
199 advwdt_ping();
200 return nonseekable_open(inode, file);
201}
202
Wim Van Sebroeck7944d3a2008-08-06 20:19:41 +0000203static int advwdt_close(struct inode *inode, struct file *file)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204{
205 if (adv_expect_close == 42) {
206 advwdt_disable();
207 } else {
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100208 printk(KERN_CRIT PFX
209 "Unexpected close, not stopping watchdog!\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 advwdt_ping();
211 }
212 clear_bit(0, &advwdt_is_open);
213 adv_expect_close = 0;
214 return 0;
215}
216
217/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700218 * Kernel Interfaces
219 */
220
Arjan van de Ven62322d22006-07-03 00:24:21 -0700221static const struct file_operations advwdt_fops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 .owner = THIS_MODULE,
223 .llseek = no_llseek,
224 .write = advwdt_write,
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100225 .unlocked_ioctl = advwdt_ioctl,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 .open = advwdt_open,
227 .release = advwdt_close,
228};
229
230static struct miscdevice advwdt_miscdev = {
Wim Van Sebroeck1d747be2007-01-11 22:19:28 +0100231 .minor = WATCHDOG_MINOR,
232 .name = "watchdog",
233 .fops = &advwdt_fops,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700234};
235
236/*
Wim Van Sebroeck1d747be2007-01-11 22:19:28 +0100237 * Init & exit routines
238 */
239
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100240static int __devinit advwdt_probe(struct platform_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241{
242 int ret;
243
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244 if (wdt_stop != wdt_start) {
245 if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) {
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100246 printk(KERN_ERR PFX
247 "I/O address 0x%04x already in use\n",
248 wdt_stop);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249 ret = -EIO;
250 goto out;
251 }
252 }
253
254 if (!request_region(wdt_start, 1, WATCHDOG_NAME)) {
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100255 printk(KERN_ERR PFX
256 "I/O address 0x%04x already in use\n",
257 wdt_start);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700258 ret = -EIO;
259 goto unreg_stop;
260 }
261
Wim Van Sebroeck0349a362007-01-11 22:27:51 +0100262 /* Check that the heartbeat value is within it's range ; if not reset to the default */
263 if (advwdt_set_heartbeat(timeout)) {
264 advwdt_set_heartbeat(WATCHDOG_TIMEOUT);
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100265 printk(KERN_INFO PFX
266 "timeout value must be 1<=x<=63, using %d\n", timeout);
Wim Van Sebroeck0349a362007-01-11 22:27:51 +0100267 }
268
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 ret = misc_register(&advwdt_miscdev);
270 if (ret != 0) {
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100271 printk(KERN_ERR PFX
272 "cannot register miscdev on minor=%d (err=%d)\n",
273 WATCHDOG_MINOR, ret);
Wim Van Sebroeck2e9c9cf2007-01-11 22:42:41 +0100274 goto unreg_regions;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700275 }
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100276 printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700277 timeout, nowayout);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278out:
279 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280unreg_regions:
281 release_region(wdt_start, 1);
282unreg_stop:
283 if (wdt_stop != wdt_start)
284 release_region(wdt_stop, 1);
285 goto out;
286}
287
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100288static int __devexit advwdt_remove(struct platform_device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700289{
290 misc_deregister(&advwdt_miscdev);
Wim Van Sebroeck7944d3a2008-08-06 20:19:41 +0000291 release_region(wdt_start, 1);
292 if (wdt_stop != wdt_start)
293 release_region(wdt_stop, 1);
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100294
295 return 0;
296}
297
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100298static void advwdt_shutdown(struct platform_device *dev)
Wim Van Sebroeck2e9c9cf2007-01-11 22:42:41 +0100299{
300 /* Turn the WDT off if we have a soft shutdown */
301 advwdt_disable();
302}
303
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100304static struct platform_driver advwdt_driver = {
305 .probe = advwdt_probe,
306 .remove = __devexit_p(advwdt_remove),
Wim Van Sebroeck2e9c9cf2007-01-11 22:42:41 +0100307 .shutdown = advwdt_shutdown,
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100308 .driver = {
309 .owner = THIS_MODULE,
310 .name = DRV_NAME,
311 },
312};
313
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100314static int __init advwdt_init(void)
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100315{
316 int err;
317
Wim Van Sebroeck7944d3a2008-08-06 20:19:41 +0000318 printk(KERN_INFO
319 "WDT driver for Advantech single board computer initialising.\n");
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100320
321 err = platform_driver_register(&advwdt_driver);
322 if (err)
323 return err;
324
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100325 advwdt_platform_device = platform_device_register_simple(DRV_NAME,
326 -1, NULL, 0);
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100327 if (IS_ERR(advwdt_platform_device)) {
328 err = PTR_ERR(advwdt_platform_device);
329 goto unreg_platform_driver;
330 }
331
332 return 0;
333
334unreg_platform_driver:
335 platform_driver_unregister(&advwdt_driver);
336 return err;
337}
338
Alan Coxb6b4d9b2008-05-19 14:04:51 +0100339static void __exit advwdt_exit(void)
Wim Van Sebroeckc2bd11c2007-01-11 22:35:40 +0100340{
341 platform_device_unregister(advwdt_platform_device);
342 platform_driver_unregister(&advwdt_driver);
343 printk(KERN_INFO PFX "Watchdog Module Unloaded.\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344}
345
346module_init(advwdt_init);
347module_exit(advwdt_exit);
348
349MODULE_LICENSE("GPL");
350MODULE_AUTHOR("Marek Michalkiewicz <marekm@linux.org.pl>");
351MODULE_DESCRIPTION("Advantech Single Board Computer WDT driver");
352MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);