Commit | Line | Data |
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1da177e4 LT |
1 | /* |
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> | |
c2bd11c7 | 38 | #include <linux/platform_device.h> |
1da177e4 LT |
39 | #include <linux/init.h> |
40 | ||
41 | #include <asm/io.h> | |
42 | #include <asm/uaccess.h> | |
43 | #include <asm/system.h> | |
44 | ||
1d747be6 WVS |
45 | #define DRV_NAME "advantechwdt" |
46 | #define PFX DRV_NAME ": " | |
1da177e4 | 47 | #define WATCHDOG_NAME "Advantech WDT" |
1da177e4 LT |
48 | #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ |
49 | ||
c2bd11c7 | 50 | static struct platform_device *advwdt_platform_device; /* the watchdog platform device */ |
1da177e4 LT |
51 | static unsigned long advwdt_is_open; |
52 | static char adv_expect_close; | |
53 | ||
54 | /* | |
55 | * You must set these - there is no sane way to probe for this board. | |
56 | * | |
57 | * To enable or restart, write the timeout value in seconds (1 to 63) | |
58 | * to I/O port wdt_start. To disable, read I/O port wdt_stop. | |
59 | * Both are 0x443 for most boards (tested on a PCA-6276VE-00B1), but | |
60 | * check your manual (at least the PCA-6159 seems to be different - | |
61 | * the manual says wdt_stop is 0x43, not 0x443). | |
62 | * (0x43 is also a write-only control register for the 8254 timer!) | |
63 | */ | |
64 | ||
65 | static int wdt_stop = 0x443; | |
66 | module_param(wdt_stop, int, 0); | |
67 | MODULE_PARM_DESC(wdt_stop, "Advantech WDT 'stop' io port (default 0x443)"); | |
68 | ||
69 | static int wdt_start = 0x443; | |
70 | module_param(wdt_start, int, 0); | |
71 | MODULE_PARM_DESC(wdt_start, "Advantech WDT 'start' io port (default 0x443)"); | |
72 | ||
73 | static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ | |
74 | module_param(timeout, int, 0); | |
75 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=63, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); | |
76 | ||
4bfdf378 | 77 | static int nowayout = WATCHDOG_NOWAYOUT; |
1da177e4 | 78 | module_param(nowayout, int, 0); |
1d747be6 | 79 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
1da177e4 LT |
80 | |
81 | /* | |
1d747be6 | 82 | * Watchdog Operations |
1da177e4 LT |
83 | */ |
84 | ||
85 | static void | |
86 | advwdt_ping(void) | |
87 | { | |
88 | /* Write a watchdog value */ | |
89 | outb_p(timeout, wdt_start); | |
90 | } | |
91 | ||
92 | static void | |
93 | advwdt_disable(void) | |
94 | { | |
95 | inb_p(wdt_stop); | |
96 | } | |
97 | ||
0349a363 WVS |
98 | static int |
99 | advwdt_set_heartbeat(int t) | |
100 | { | |
101 | if ((t < 1) || (t > 63)) | |
102 | return -EINVAL; | |
103 | ||
104 | timeout = t; | |
105 | return 0; | |
106 | } | |
107 | ||
1d747be6 WVS |
108 | /* |
109 | * /dev/watchdog handling | |
110 | */ | |
111 | ||
1da177e4 LT |
112 | static ssize_t |
113 | advwdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) | |
114 | { | |
115 | if (count) { | |
116 | if (!nowayout) { | |
117 | size_t i; | |
118 | ||
119 | adv_expect_close = 0; | |
120 | ||
121 | for (i = 0; i != count; i++) { | |
122 | char c; | |
123 | if (get_user(c, buf+i)) | |
124 | return -EFAULT; | |
125 | if (c == 'V') | |
126 | adv_expect_close = 42; | |
127 | } | |
128 | } | |
129 | advwdt_ping(); | |
130 | } | |
131 | return count; | |
132 | } | |
133 | ||
134 | static int | |
135 | advwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | |
136 | unsigned long arg) | |
137 | { | |
138 | int new_timeout; | |
139 | void __user *argp = (void __user *)arg; | |
140 | int __user *p = argp; | |
141 | static struct watchdog_info ident = { | |
142 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, | |
143 | .firmware_version = 1, | |
1d747be6 | 144 | .identity = WATCHDOG_NAME, |
1da177e4 LT |
145 | }; |
146 | ||
147 | switch (cmd) { | |
148 | case WDIOC_GETSUPPORT: | |
149 | if (copy_to_user(argp, &ident, sizeof(ident))) | |
150 | return -EFAULT; | |
151 | break; | |
152 | ||
153 | case WDIOC_GETSTATUS: | |
154 | case WDIOC_GETBOOTSTATUS: | |
155 | return put_user(0, p); | |
156 | ||
157 | case WDIOC_KEEPALIVE: | |
158 | advwdt_ping(); | |
159 | break; | |
160 | ||
161 | case WDIOC_SETTIMEOUT: | |
162 | if (get_user(new_timeout, p)) | |
163 | return -EFAULT; | |
0349a363 | 164 | if (advwdt_set_heartbeat(new_timeout)) |
1da177e4 | 165 | return -EINVAL; |
1da177e4 LT |
166 | advwdt_ping(); |
167 | /* Fall */ | |
168 | ||
169 | case WDIOC_GETTIMEOUT: | |
170 | return put_user(timeout, p); | |
171 | ||
172 | case WDIOC_SETOPTIONS: | |
173 | { | |
174 | int options, retval = -EINVAL; | |
175 | ||
176 | if (get_user(options, p)) | |
177 | return -EFAULT; | |
178 | ||
179 | if (options & WDIOS_DISABLECARD) { | |
180 | advwdt_disable(); | |
181 | retval = 0; | |
182 | } | |
183 | ||
184 | if (options & WDIOS_ENABLECARD) { | |
185 | advwdt_ping(); | |
186 | retval = 0; | |
187 | } | |
188 | ||
189 | return retval; | |
190 | } | |
191 | ||
192 | default: | |
795b89d2 | 193 | return -ENOTTY; |
1da177e4 LT |
194 | } |
195 | return 0; | |
196 | } | |
197 | ||
198 | static int | |
199 | advwdt_open(struct inode *inode, struct file *file) | |
200 | { | |
201 | if (test_and_set_bit(0, &advwdt_is_open)) | |
202 | return -EBUSY; | |
203 | /* | |
204 | * Activate | |
205 | */ | |
206 | ||
207 | advwdt_ping(); | |
208 | return nonseekable_open(inode, file); | |
209 | } | |
210 | ||
211 | static int | |
212 | advwdt_close(struct inode *inode, struct file *file) | |
213 | { | |
214 | if (adv_expect_close == 42) { | |
215 | advwdt_disable(); | |
216 | } else { | |
217 | printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n"); | |
218 | advwdt_ping(); | |
219 | } | |
220 | clear_bit(0, &advwdt_is_open); | |
221 | adv_expect_close = 0; | |
222 | return 0; | |
223 | } | |
224 | ||
1da177e4 LT |
225 | /* |
226 | * Kernel Interfaces | |
227 | */ | |
228 | ||
62322d25 | 229 | static const struct file_operations advwdt_fops = { |
1da177e4 LT |
230 | .owner = THIS_MODULE, |
231 | .llseek = no_llseek, | |
232 | .write = advwdt_write, | |
233 | .ioctl = advwdt_ioctl, | |
234 | .open = advwdt_open, | |
235 | .release = advwdt_close, | |
236 | }; | |
237 | ||
238 | static struct miscdevice advwdt_miscdev = { | |
1d747be6 WVS |
239 | .minor = WATCHDOG_MINOR, |
240 | .name = "watchdog", | |
241 | .fops = &advwdt_fops, | |
1da177e4 LT |
242 | }; |
243 | ||
1d747be6 WVS |
244 | /* |
245 | * Init & exit routines | |
246 | */ | |
247 | ||
c2bd11c7 WVS |
248 | static int __devinit |
249 | advwdt_probe(struct platform_device *dev) | |
1da177e4 LT |
250 | { |
251 | int ret; | |
252 | ||
1da177e4 LT |
253 | if (wdt_stop != wdt_start) { |
254 | if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) { | |
255 | printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", | |
256 | wdt_stop); | |
257 | ret = -EIO; | |
258 | goto out; | |
259 | } | |
260 | } | |
261 | ||
262 | if (!request_region(wdt_start, 1, WATCHDOG_NAME)) { | |
263 | printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", | |
264 | wdt_start); | |
265 | ret = -EIO; | |
266 | goto unreg_stop; | |
267 | } | |
268 | ||
0349a363 WVS |
269 | /* Check that the heartbeat value is within it's range ; if not reset to the default */ |
270 | if (advwdt_set_heartbeat(timeout)) { | |
271 | advwdt_set_heartbeat(WATCHDOG_TIMEOUT); | |
272 | printk (KERN_INFO PFX "timeout value must be 1<=x<=63, using %d\n", | |
273 | timeout); | |
274 | } | |
275 | ||
1da177e4 LT |
276 | ret = misc_register(&advwdt_miscdev); |
277 | if (ret != 0) { | |
278 | printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | |
279 | WATCHDOG_MINOR, ret); | |
2e9c9cf4 | 280 | goto unreg_regions; |
1da177e4 LT |
281 | } |
282 | ||
283 | printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n", | |
284 | timeout, nowayout); | |
285 | ||
286 | out: | |
287 | return ret; | |
1da177e4 LT |
288 | unreg_regions: |
289 | release_region(wdt_start, 1); | |
290 | unreg_stop: | |
291 | if (wdt_stop != wdt_start) | |
292 | release_region(wdt_stop, 1); | |
293 | goto out; | |
294 | } | |
295 | ||
c2bd11c7 WVS |
296 | static int __devexit |
297 | advwdt_remove(struct platform_device *dev) | |
1da177e4 LT |
298 | { |
299 | misc_deregister(&advwdt_miscdev); | |
1d747be6 | 300 | release_region(wdt_start,1); |
1da177e4 LT |
301 | if(wdt_stop != wdt_start) |
302 | release_region(wdt_stop,1); | |
c2bd11c7 WVS |
303 | |
304 | return 0; | |
305 | } | |
306 | ||
2e9c9cf4 WVS |
307 | static void |
308 | advwdt_shutdown(struct platform_device *dev) | |
309 | { | |
310 | /* Turn the WDT off if we have a soft shutdown */ | |
311 | advwdt_disable(); | |
312 | } | |
313 | ||
c2bd11c7 WVS |
314 | static struct platform_driver advwdt_driver = { |
315 | .probe = advwdt_probe, | |
316 | .remove = __devexit_p(advwdt_remove), | |
2e9c9cf4 | 317 | .shutdown = advwdt_shutdown, |
c2bd11c7 WVS |
318 | .driver = { |
319 | .owner = THIS_MODULE, | |
320 | .name = DRV_NAME, | |
321 | }, | |
322 | }; | |
323 | ||
324 | static int __init | |
325 | advwdt_init(void) | |
326 | { | |
327 | int err; | |
328 | ||
329 | printk(KERN_INFO "WDT driver for Advantech single board computer initialising.\n"); | |
330 | ||
331 | err = platform_driver_register(&advwdt_driver); | |
332 | if (err) | |
333 | return err; | |
334 | ||
335 | advwdt_platform_device = platform_device_register_simple(DRV_NAME, -1, NULL, 0); | |
336 | if (IS_ERR(advwdt_platform_device)) { | |
337 | err = PTR_ERR(advwdt_platform_device); | |
338 | goto unreg_platform_driver; | |
339 | } | |
340 | ||
341 | return 0; | |
342 | ||
343 | unreg_platform_driver: | |
344 | platform_driver_unregister(&advwdt_driver); | |
345 | return err; | |
346 | } | |
347 | ||
348 | static void __exit | |
349 | advwdt_exit(void) | |
350 | { | |
351 | platform_device_unregister(advwdt_platform_device); | |
352 | platform_driver_unregister(&advwdt_driver); | |
353 | printk(KERN_INFO PFX "Watchdog Module Unloaded.\n"); | |
1da177e4 LT |
354 | } |
355 | ||
356 | module_init(advwdt_init); | |
357 | module_exit(advwdt_exit); | |
358 | ||
359 | MODULE_LICENSE("GPL"); | |
360 | MODULE_AUTHOR("Marek Michalkiewicz <marekm@linux.org.pl>"); | |
361 | MODULE_DESCRIPTION("Advantech Single Board Computer WDT driver"); | |
362 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |