Commit | Line | Data |
---|---|---|
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 | ||
27c766aa JP |
31 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
32 | ||
1da177e4 LT |
33 | #include <linux/module.h> |
34 | #include <linux/moduleparam.h> | |
35 | #include <linux/types.h> | |
36 | #include <linux/miscdevice.h> | |
37 | #include <linux/watchdog.h> | |
38 | #include <linux/fs.h> | |
39 | #include <linux/ioport.h> | |
c2bd11c7 | 40 | #include <linux/platform_device.h> |
1da177e4 | 41 | #include <linux/init.h> |
089ab079 WVS |
42 | #include <linux/io.h> |
43 | #include <linux/uaccess.h> | |
1da177e4 | 44 | |
1da177e4 | 45 | |
1d747be6 | 46 | #define DRV_NAME "advantechwdt" |
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 | |
86a1e189 WVS |
80 | static bool nowayout = WATCHDOG_NOWAYOUT; |
81 | module_param(nowayout, bool, 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 { | |
27c766aa | 210 | pr_crit("Unexpected close, not stopping watchdog!\n"); |
1da177e4 LT |
211 | advwdt_ping(); |
212 | } | |
213 | clear_bit(0, &advwdt_is_open); | |
214 | adv_expect_close = 0; | |
215 | return 0; | |
216 | } | |
217 | ||
1da177e4 LT |
218 | /* |
219 | * Kernel Interfaces | |
220 | */ | |
221 | ||
62322d25 | 222 | static const struct file_operations advwdt_fops = { |
1da177e4 LT |
223 | .owner = THIS_MODULE, |
224 | .llseek = no_llseek, | |
225 | .write = advwdt_write, | |
b6b4d9b8 | 226 | .unlocked_ioctl = advwdt_ioctl, |
1da177e4 LT |
227 | .open = advwdt_open, |
228 | .release = advwdt_close, | |
229 | }; | |
230 | ||
231 | static struct miscdevice advwdt_miscdev = { | |
1d747be6 WVS |
232 | .minor = WATCHDOG_MINOR, |
233 | .name = "watchdog", | |
234 | .fops = &advwdt_fops, | |
1da177e4 LT |
235 | }; |
236 | ||
1d747be6 WVS |
237 | /* |
238 | * Init & exit routines | |
239 | */ | |
240 | ||
acaaaf62 | 241 | static int __init advwdt_probe(struct platform_device *dev) |
1da177e4 LT |
242 | { |
243 | int ret; | |
244 | ||
1da177e4 LT |
245 | if (wdt_stop != wdt_start) { |
246 | if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) { | |
27c766aa JP |
247 | pr_err("I/O address 0x%04x already in use\n", |
248 | wdt_stop); | |
1da177e4 LT |
249 | ret = -EIO; |
250 | goto out; | |
251 | } | |
252 | } | |
253 | ||
254 | if (!request_region(wdt_start, 1, WATCHDOG_NAME)) { | |
27c766aa | 255 | pr_err("I/O address 0x%04x already in use\n", wdt_start); |
1da177e4 LT |
256 | ret = -EIO; |
257 | goto unreg_stop; | |
258 | } | |
259 | ||
143a2e54 WVS |
260 | /* Check that the heartbeat value is within it's range ; |
261 | * if not reset to the default */ | |
0349a363 WVS |
262 | if (advwdt_set_heartbeat(timeout)) { |
263 | advwdt_set_heartbeat(WATCHDOG_TIMEOUT); | |
27c766aa | 264 | pr_info("timeout value must be 1<=x<=63, using %d\n", timeout); |
0349a363 WVS |
265 | } |
266 | ||
1da177e4 LT |
267 | ret = misc_register(&advwdt_miscdev); |
268 | if (ret != 0) { | |
27c766aa JP |
269 | pr_err("cannot register miscdev on minor=%d (err=%d)\n", |
270 | WATCHDOG_MINOR, ret); | |
2e9c9cf4 | 271 | goto unreg_regions; |
1da177e4 | 272 | } |
27c766aa | 273 | pr_info("initialized. timeout=%d sec (nowayout=%d)\n", |
1da177e4 | 274 | timeout, nowayout); |
1da177e4 LT |
275 | out: |
276 | return ret; | |
1da177e4 LT |
277 | unreg_regions: |
278 | release_region(wdt_start, 1); | |
279 | unreg_stop: | |
280 | if (wdt_stop != wdt_start) | |
281 | release_region(wdt_stop, 1); | |
282 | goto out; | |
283 | } | |
284 | ||
4b12b896 | 285 | static int advwdt_remove(struct platform_device *dev) |
1da177e4 LT |
286 | { |
287 | misc_deregister(&advwdt_miscdev); | |
7944d3a5 WVS |
288 | release_region(wdt_start, 1); |
289 | if (wdt_stop != wdt_start) | |
290 | release_region(wdt_stop, 1); | |
c2bd11c7 WVS |
291 | |
292 | return 0; | |
293 | } | |
294 | ||
b6b4d9b8 | 295 | static void advwdt_shutdown(struct platform_device *dev) |
2e9c9cf4 WVS |
296 | { |
297 | /* Turn the WDT off if we have a soft shutdown */ | |
298 | advwdt_disable(); | |
299 | } | |
300 | ||
c2bd11c7 | 301 | static struct platform_driver advwdt_driver = { |
82268714 | 302 | .remove = advwdt_remove, |
2e9c9cf4 | 303 | .shutdown = advwdt_shutdown, |
c2bd11c7 | 304 | .driver = { |
c2bd11c7 WVS |
305 | .name = DRV_NAME, |
306 | }, | |
307 | }; | |
308 | ||
b6b4d9b8 | 309 | static int __init advwdt_init(void) |
c2bd11c7 WVS |
310 | { |
311 | int err; | |
312 | ||
27c766aa | 313 | pr_info("WDT driver for Advantech single board computer initialising\n"); |
c2bd11c7 | 314 | |
b6b4d9b8 AC |
315 | advwdt_platform_device = platform_device_register_simple(DRV_NAME, |
316 | -1, NULL, 0); | |
acaaaf62 JD |
317 | if (IS_ERR(advwdt_platform_device)) |
318 | return PTR_ERR(advwdt_platform_device); | |
319 | ||
320 | err = platform_driver_probe(&advwdt_driver, advwdt_probe); | |
321 | if (err) | |
322 | goto unreg_platform_device; | |
c2bd11c7 WVS |
323 | |
324 | return 0; | |
325 | ||
acaaaf62 JD |
326 | unreg_platform_device: |
327 | platform_device_unregister(advwdt_platform_device); | |
c2bd11c7 WVS |
328 | return err; |
329 | } | |
330 | ||
b6b4d9b8 | 331 | static void __exit advwdt_exit(void) |
c2bd11c7 WVS |
332 | { |
333 | platform_device_unregister(advwdt_platform_device); | |
334 | platform_driver_unregister(&advwdt_driver); | |
27c766aa | 335 | pr_info("Watchdog Module Unloaded\n"); |
1da177e4 LT |
336 | } |
337 | ||
338 | module_init(advwdt_init); | |
339 | module_exit(advwdt_exit); | |
340 | ||
341 | MODULE_LICENSE("GPL"); | |
342 | MODULE_AUTHOR("Marek Michalkiewicz <marekm@linux.org.pl>"); | |
343 | MODULE_DESCRIPTION("Advantech Single Board Computer WDT driver"); |