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 | * | |
29fa0586 AC |
9 | * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>, |
10 | * All Rights Reserved. | |
1da177e4 LT |
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 | * | |
29fa0586 | 21 | * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
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 | 39 | #include <linux/init.h> |
089ab079 WVS |
40 | #include <linux/io.h> |
41 | #include <linux/uaccess.h> | |
1da177e4 | 42 | |
1da177e4 LT |
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 | ||
7944d3a5 WVS |
50 | /* the watchdog platform device */ |
51 | static struct platform_device *advwdt_platform_device; | |
1da177e4 LT |
52 | static unsigned long advwdt_is_open; |
53 | static 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 | ||
66 | static int wdt_stop = 0x443; | |
67 | module_param(wdt_stop, int, 0); | |
68 | MODULE_PARM_DESC(wdt_stop, "Advantech WDT 'stop' io port (default 0x443)"); | |
69 | ||
70 | static int wdt_start = 0x443; | |
71 | module_param(wdt_start, int, 0); | |
72 | MODULE_PARM_DESC(wdt_start, "Advantech WDT 'start' io port (default 0x443)"); | |
73 | ||
74 | static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ | |
75 | module_param(timeout, int, 0); | |
b6b4d9b8 AC |
76 | MODULE_PARM_DESC(timeout, |
77 | "Watchdog timeout in seconds. 1<= timeout <=63, default=" | |
78 | __MODULE_STRING(WATCHDOG_TIMEOUT) "."); | |
1da177e4 | 79 | |
4bfdf378 | 80 | static int nowayout = WATCHDOG_NOWAYOUT; |
1da177e4 | 81 | module_param(nowayout, int, 0); |
b6b4d9b8 AC |
82 | MODULE_PARM_DESC(nowayout, |
83 | "Watchdog cannot be stopped once started (default=" | |
84 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | |
1da177e4 LT |
85 | |
86 | /* | |
1d747be6 | 87 | * Watchdog Operations |
1da177e4 LT |
88 | */ |
89 | ||
b6b4d9b8 | 90 | static void advwdt_ping(void) |
1da177e4 LT |
91 | { |
92 | /* Write a watchdog value */ | |
93 | outb_p(timeout, wdt_start); | |
94 | } | |
95 | ||
b6b4d9b8 | 96 | static void advwdt_disable(void) |
1da177e4 LT |
97 | { |
98 | inb_p(wdt_stop); | |
99 | } | |
100 | ||
b6b4d9b8 | 101 | static int advwdt_set_heartbeat(int t) |
0349a363 | 102 | { |
b6b4d9b8 | 103 | if (t < 1 || t > 63) |
0349a363 | 104 | return -EINVAL; |
0349a363 WVS |
105 | timeout = t; |
106 | return 0; | |
107 | } | |
108 | ||
1d747be6 WVS |
109 | /* |
110 | * /dev/watchdog handling | |
111 | */ | |
112 | ||
b6b4d9b8 AC |
113 | static ssize_t advwdt_write(struct file *file, const char __user *buf, |
114 | size_t count, loff_t *ppos) | |
1da177e4 LT |
115 | { |
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; | |
7944d3a5 | 124 | if (get_user(c, buf + i)) |
1da177e4 LT |
125 | return -EFAULT; |
126 | if (c == 'V') | |
127 | adv_expect_close = 42; | |
128 | } | |
129 | } | |
130 | advwdt_ping(); | |
131 | } | |
132 | return count; | |
133 | } | |
134 | ||
b6b4d9b8 | 135 | static long advwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
1da177e4 LT |
136 | { |
137 | int new_timeout; | |
138 | void __user *argp = (void __user *)arg; | |
139 | int __user *p = argp; | |
42747d71 | 140 | static const struct watchdog_info ident = { |
143a2e54 WVS |
141 | .options = WDIOF_KEEPALIVEPING | |
142 | WDIOF_SETTIMEOUT | | |
143 | WDIOF_MAGICCLOSE, | |
1da177e4 | 144 | .firmware_version = 1, |
1d747be6 | 145 | .identity = WATCHDOG_NAME, |
1da177e4 LT |
146 | }; |
147 | ||
148 | switch (cmd) { | |
149 | case WDIOC_GETSUPPORT: | |
b6b4d9b8 AC |
150 | if (copy_to_user(argp, &ident, sizeof(ident))) |
151 | return -EFAULT; | |
152 | break; | |
1da177e4 LT |
153 | |
154 | case WDIOC_GETSTATUS: | |
155 | case WDIOC_GETBOOTSTATUS: | |
b6b4d9b8 | 156 | return put_user(0, p); |
1da177e4 | 157 | |
1da177e4 LT |
158 | case WDIOC_SETOPTIONS: |
159 | { | |
b6b4d9b8 | 160 | int options, retval = -EINVAL; |
1da177e4 | 161 | |
b6b4d9b8 AC |
162 | if (get_user(options, p)) |
163 | return -EFAULT; | |
164 | if (options & WDIOS_DISABLECARD) { | |
165 | advwdt_disable(); | |
166 | retval = 0; | |
167 | } | |
168 | if (options & WDIOS_ENABLECARD) { | |
169 | advwdt_ping(); | |
170 | retval = 0; | |
171 | } | |
172 | return retval; | |
1da177e4 | 173 | } |
0c06090c WVS |
174 | case WDIOC_KEEPALIVE: |
175 | advwdt_ping(); | |
176 | break; | |
177 | ||
178 | case WDIOC_SETTIMEOUT: | |
179 | if (get_user(new_timeout, p)) | |
180 | return -EFAULT; | |
181 | if (advwdt_set_heartbeat(new_timeout)) | |
182 | return -EINVAL; | |
183 | advwdt_ping(); | |
184 | /* Fall */ | |
185 | case WDIOC_GETTIMEOUT: | |
186 | return put_user(timeout, p); | |
1da177e4 | 187 | default: |
b6b4d9b8 | 188 | return -ENOTTY; |
1da177e4 LT |
189 | } |
190 | return 0; | |
191 | } | |
192 | ||
b6b4d9b8 | 193 | static int advwdt_open(struct inode *inode, struct file *file) |
1da177e4 LT |
194 | { |
195 | if (test_and_set_bit(0, &advwdt_is_open)) | |
196 | return -EBUSY; | |
197 | /* | |
198 | * Activate | |
199 | */ | |
200 | ||
201 | advwdt_ping(); | |
202 | return nonseekable_open(inode, file); | |
203 | } | |
204 | ||
7944d3a5 | 205 | static int advwdt_close(struct inode *inode, struct file *file) |
1da177e4 LT |
206 | { |
207 | if (adv_expect_close == 42) { | |
208 | advwdt_disable(); | |
209 | } else { | |
b6b4d9b8 AC |
210 | printk(KERN_CRIT PFX |
211 | "Unexpected close, not stopping watchdog!\n"); | |
1da177e4 LT |
212 | advwdt_ping(); |
213 | } | |
214 | clear_bit(0, &advwdt_is_open); | |
215 | adv_expect_close = 0; | |
216 | return 0; | |
217 | } | |
218 | ||
1da177e4 LT |
219 | /* |
220 | * Kernel Interfaces | |
221 | */ | |
222 | ||
62322d25 | 223 | static const struct file_operations advwdt_fops = { |
1da177e4 LT |
224 | .owner = THIS_MODULE, |
225 | .llseek = no_llseek, | |
226 | .write = advwdt_write, | |
b6b4d9b8 | 227 | .unlocked_ioctl = advwdt_ioctl, |
1da177e4 LT |
228 | .open = advwdt_open, |
229 | .release = advwdt_close, | |
230 | }; | |
231 | ||
232 | static struct miscdevice advwdt_miscdev = { | |
1d747be6 WVS |
233 | .minor = WATCHDOG_MINOR, |
234 | .name = "watchdog", | |
235 | .fops = &advwdt_fops, | |
1da177e4 LT |
236 | }; |
237 | ||
1d747be6 WVS |
238 | /* |
239 | * Init & exit routines | |
240 | */ | |
241 | ||
b6b4d9b8 | 242 | static int __devinit advwdt_probe(struct platform_device *dev) |
1da177e4 LT |
243 | { |
244 | int ret; | |
245 | ||
1da177e4 LT |
246 | if (wdt_stop != wdt_start) { |
247 | if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) { | |
b6b4d9b8 AC |
248 | printk(KERN_ERR PFX |
249 | "I/O address 0x%04x already in use\n", | |
250 | wdt_stop); | |
1da177e4 LT |
251 | ret = -EIO; |
252 | goto out; | |
253 | } | |
254 | } | |
255 | ||
256 | if (!request_region(wdt_start, 1, WATCHDOG_NAME)) { | |
b6b4d9b8 AC |
257 | printk(KERN_ERR PFX |
258 | "I/O address 0x%04x already in use\n", | |
259 | wdt_start); | |
1da177e4 LT |
260 | ret = -EIO; |
261 | goto unreg_stop; | |
262 | } | |
263 | ||
143a2e54 WVS |
264 | /* Check that the heartbeat value is within it's range ; |
265 | * if not reset to the default */ | |
0349a363 WVS |
266 | if (advwdt_set_heartbeat(timeout)) { |
267 | advwdt_set_heartbeat(WATCHDOG_TIMEOUT); | |
b6b4d9b8 AC |
268 | printk(KERN_INFO PFX |
269 | "timeout value must be 1<=x<=63, using %d\n", timeout); | |
0349a363 WVS |
270 | } |
271 | ||
1da177e4 LT |
272 | ret = misc_register(&advwdt_miscdev); |
273 | if (ret != 0) { | |
b6b4d9b8 AC |
274 | printk(KERN_ERR PFX |
275 | "cannot register miscdev on minor=%d (err=%d)\n", | |
276 | WATCHDOG_MINOR, ret); | |
2e9c9cf4 | 277 | goto unreg_regions; |
1da177e4 | 278 | } |
b6b4d9b8 | 279 | printk(KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n", |
1da177e4 | 280 | timeout, nowayout); |
1da177e4 LT |
281 | out: |
282 | return ret; | |
1da177e4 LT |
283 | unreg_regions: |
284 | release_region(wdt_start, 1); | |
285 | unreg_stop: | |
286 | if (wdt_stop != wdt_start) | |
287 | release_region(wdt_stop, 1); | |
288 | goto out; | |
289 | } | |
290 | ||
b6b4d9b8 | 291 | static int __devexit advwdt_remove(struct platform_device *dev) |
1da177e4 LT |
292 | { |
293 | misc_deregister(&advwdt_miscdev); | |
7944d3a5 WVS |
294 | release_region(wdt_start, 1); |
295 | if (wdt_stop != wdt_start) | |
296 | release_region(wdt_stop, 1); | |
c2bd11c7 WVS |
297 | |
298 | return 0; | |
299 | } | |
300 | ||
b6b4d9b8 | 301 | static void advwdt_shutdown(struct platform_device *dev) |
2e9c9cf4 WVS |
302 | { |
303 | /* Turn the WDT off if we have a soft shutdown */ | |
304 | advwdt_disable(); | |
305 | } | |
306 | ||
c2bd11c7 WVS |
307 | static struct platform_driver advwdt_driver = { |
308 | .probe = advwdt_probe, | |
309 | .remove = __devexit_p(advwdt_remove), | |
2e9c9cf4 | 310 | .shutdown = advwdt_shutdown, |
c2bd11c7 WVS |
311 | .driver = { |
312 | .owner = THIS_MODULE, | |
313 | .name = DRV_NAME, | |
314 | }, | |
315 | }; | |
316 | ||
b6b4d9b8 | 317 | static int __init advwdt_init(void) |
c2bd11c7 WVS |
318 | { |
319 | int err; | |
320 | ||
7944d3a5 WVS |
321 | printk(KERN_INFO |
322 | "WDT driver for Advantech single board computer initialising.\n"); | |
c2bd11c7 WVS |
323 | |
324 | err = platform_driver_register(&advwdt_driver); | |
325 | if (err) | |
326 | return err; | |
327 | ||
b6b4d9b8 AC |
328 | advwdt_platform_device = platform_device_register_simple(DRV_NAME, |
329 | -1, NULL, 0); | |
c2bd11c7 WVS |
330 | if (IS_ERR(advwdt_platform_device)) { |
331 | err = PTR_ERR(advwdt_platform_device); | |
332 | goto unreg_platform_driver; | |
333 | } | |
334 | ||
335 | return 0; | |
336 | ||
337 | unreg_platform_driver: | |
338 | platform_driver_unregister(&advwdt_driver); | |
339 | return err; | |
340 | } | |
341 | ||
b6b4d9b8 | 342 | static void __exit advwdt_exit(void) |
c2bd11c7 WVS |
343 | { |
344 | platform_device_unregister(advwdt_platform_device); | |
345 | platform_driver_unregister(&advwdt_driver); | |
346 | printk(KERN_INFO PFX "Watchdog Module Unloaded.\n"); | |
1da177e4 LT |
347 | } |
348 | ||
349 | module_init(advwdt_init); | |
350 | module_exit(advwdt_exit); | |
351 | ||
352 | MODULE_LICENSE("GPL"); | |
353 | MODULE_AUTHOR("Marek Michalkiewicz <marekm@linux.org.pl>"); | |
354 | MODULE_DESCRIPTION("Advantech Single Board Computer WDT driver"); | |
355 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |