diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/char/watchdog/wafer5823wdt.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'drivers/char/watchdog/wafer5823wdt.c')
-rw-r--r-- | drivers/char/watchdog/wafer5823wdt.c | 330 |
1 files changed, 330 insertions, 0 deletions
diff --git a/drivers/char/watchdog/wafer5823wdt.c b/drivers/char/watchdog/wafer5823wdt.c new file mode 100644 index 000000000000..abb0bea45c02 --- /dev/null +++ b/drivers/char/watchdog/wafer5823wdt.c | |||
@@ -0,0 +1,330 @@ | |||
1 | /* | ||
2 | * ICP Wafer 5823 Single Board Computer WDT driver | ||
3 | * http://www.icpamerica.com/wafer_5823.php | ||
4 | * May also work on other similar models | ||
5 | * | ||
6 | * (c) Copyright 2002 Justin Cormack <justin@street-vision.com> | ||
7 | * | ||
8 | * Release 0.02 | ||
9 | * | ||
10 | * Based on advantechwdt.c which is based on wdt.c. | ||
11 | * Original copyright messages: | ||
12 | * | ||
13 | * (c) Copyright 1996-1997 Alan Cox <alan@redhat.com>, All Rights Reserved. | ||
14 | * http://www.redhat.com | ||
15 | * | ||
16 | * This program is free software; you can redistribute it and/or | ||
17 | * modify it under the terms of the GNU General Public License | ||
18 | * as published by the Free Software Foundation; either version | ||
19 | * 2 of the License, or (at your option) any later version. | ||
20 | * | ||
21 | * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide | ||
22 | * warranty for any of this software. This material is provided | ||
23 | * "AS-IS" and at no charge. | ||
24 | * | ||
25 | * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk> | ||
26 | * | ||
27 | */ | ||
28 | |||
29 | #include <linux/module.h> | ||
30 | #include <linux/moduleparam.h> | ||
31 | #include <linux/miscdevice.h> | ||
32 | #include <linux/watchdog.h> | ||
33 | #include <linux/fs.h> | ||
34 | #include <linux/ioport.h> | ||
35 | #include <linux/notifier.h> | ||
36 | #include <linux/reboot.h> | ||
37 | #include <linux/init.h> | ||
38 | #include <linux/spinlock.h> | ||
39 | #include <asm/io.h> | ||
40 | #include <asm/uaccess.h> | ||
41 | |||
42 | #define WATCHDOG_NAME "Wafer 5823 WDT" | ||
43 | #define PFX WATCHDOG_NAME ": " | ||
44 | #define WD_TIMO 60 /* 60 sec default timeout */ | ||
45 | |||
46 | static unsigned long wafwdt_is_open; | ||
47 | static char expect_close; | ||
48 | static spinlock_t wafwdt_lock; | ||
49 | |||
50 | /* | ||
51 | * You must set these - there is no sane way to probe for this board. | ||
52 | * | ||
53 | * To enable, write the timeout value in seconds (1 to 255) to I/O | ||
54 | * port WDT_START, then read the port to start the watchdog. To pat | ||
55 | * the dog, read port WDT_STOP to stop the timer, then read WDT_START | ||
56 | * to restart it again. | ||
57 | */ | ||
58 | |||
59 | static int wdt_stop = 0x843; | ||
60 | static int wdt_start = 0x443; | ||
61 | |||
62 | static int timeout = WD_TIMO; /* in seconds */ | ||
63 | module_param(timeout, int, 0); | ||
64 | MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, default=" __MODULE_STRING(WD_TIMO) "."); | ||
65 | |||
66 | #ifdef CONFIG_WATCHDOG_NOWAYOUT | ||
67 | static int nowayout = 1; | ||
68 | #else | ||
69 | static int nowayout = 0; | ||
70 | #endif | ||
71 | |||
72 | module_param(nowayout, int, 0); | ||
73 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); | ||
74 | |||
75 | static void wafwdt_ping(void) | ||
76 | { | ||
77 | /* pat watchdog */ | ||
78 | spin_lock(&wafwdt_lock); | ||
79 | inb_p(wdt_stop); | ||
80 | inb_p(wdt_start); | ||
81 | spin_unlock(&wafwdt_lock); | ||
82 | } | ||
83 | |||
84 | static void wafwdt_start(void) | ||
85 | { | ||
86 | /* start up watchdog */ | ||
87 | outb_p(timeout, wdt_start); | ||
88 | inb_p(wdt_start); | ||
89 | } | ||
90 | |||
91 | static void | ||
92 | wafwdt_stop(void) | ||
93 | { | ||
94 | /* stop watchdog */ | ||
95 | inb_p(wdt_stop); | ||
96 | } | ||
97 | |||
98 | static ssize_t wafwdt_write(struct file *file, const char __user *buf, size_t count, loff_t * ppos) | ||
99 | { | ||
100 | /* See if we got the magic character 'V' and reload the timer */ | ||
101 | if (count) { | ||
102 | if (!nowayout) { | ||
103 | size_t i; | ||
104 | |||
105 | /* In case it was set long ago */ | ||
106 | expect_close = 0; | ||
107 | |||
108 | /* scan to see whether or not we got the magic character */ | ||
109 | for (i = 0; i != count; i++) { | ||
110 | char c; | ||
111 | if (get_user(c, buf + i)) | ||
112 | return -EFAULT; | ||
113 | if (c == 'V') | ||
114 | expect_close = 42; | ||
115 | } | ||
116 | } | ||
117 | /* Well, anyhow someone wrote to us, we should return that favour */ | ||
118 | wafwdt_ping(); | ||
119 | } | ||
120 | return count; | ||
121 | } | ||
122 | |||
123 | static int wafwdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | ||
124 | unsigned long arg) | ||
125 | { | ||
126 | int new_timeout; | ||
127 | void __user *argp = (void __user *)arg; | ||
128 | int __user *p = argp; | ||
129 | static struct watchdog_info ident = { | ||
130 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, | ||
131 | .firmware_version = 1, | ||
132 | .identity = "Wafer 5823 WDT", | ||
133 | }; | ||
134 | |||
135 | switch (cmd) { | ||
136 | case WDIOC_GETSUPPORT: | ||
137 | if (copy_to_user(argp, &ident, sizeof (ident))) | ||
138 | return -EFAULT; | ||
139 | break; | ||
140 | |||
141 | case WDIOC_GETSTATUS: | ||
142 | case WDIOC_GETBOOTSTATUS: | ||
143 | return put_user(0, p); | ||
144 | |||
145 | case WDIOC_KEEPALIVE: | ||
146 | wafwdt_ping(); | ||
147 | break; | ||
148 | |||
149 | case WDIOC_SETTIMEOUT: | ||
150 | if (get_user(new_timeout, p)) | ||
151 | return -EFAULT; | ||
152 | if ((new_timeout < 1) || (new_timeout > 255)) | ||
153 | return -EINVAL; | ||
154 | timeout = new_timeout; | ||
155 | wafwdt_stop(); | ||
156 | wafwdt_start(); | ||
157 | /* Fall */ | ||
158 | case WDIOC_GETTIMEOUT: | ||
159 | return put_user(timeout, p); | ||
160 | |||
161 | case WDIOC_SETOPTIONS: | ||
162 | { | ||
163 | int options, retval = -EINVAL; | ||
164 | |||
165 | if (get_user(options, p)) | ||
166 | return -EFAULT; | ||
167 | |||
168 | if (options & WDIOS_DISABLECARD) { | ||
169 | wafwdt_start(); | ||
170 | retval = 0; | ||
171 | } | ||
172 | |||
173 | if (options & WDIOS_ENABLECARD) { | ||
174 | wafwdt_stop(); | ||
175 | retval = 0; | ||
176 | } | ||
177 | |||
178 | return retval; | ||
179 | } | ||
180 | |||
181 | default: | ||
182 | return -ENOIOCTLCMD; | ||
183 | } | ||
184 | return 0; | ||
185 | } | ||
186 | |||
187 | static int wafwdt_open(struct inode *inode, struct file *file) | ||
188 | { | ||
189 | if (test_and_set_bit(0, &wafwdt_is_open)) | ||
190 | return -EBUSY; | ||
191 | |||
192 | /* | ||
193 | * Activate | ||
194 | */ | ||
195 | wafwdt_start(); | ||
196 | return nonseekable_open(inode, file); | ||
197 | } | ||
198 | |||
199 | static int | ||
200 | wafwdt_close(struct inode *inode, struct file *file) | ||
201 | { | ||
202 | if (expect_close == 42) { | ||
203 | wafwdt_stop(); | ||
204 | } else { | ||
205 | printk(KERN_CRIT PFX "WDT device closed unexpectedly. WDT will not stop!\n"); | ||
206 | wafwdt_ping(); | ||
207 | } | ||
208 | clear_bit(0, &wafwdt_is_open); | ||
209 | expect_close = 0; | ||
210 | return 0; | ||
211 | } | ||
212 | |||
213 | /* | ||
214 | * Notifier for system down | ||
215 | */ | ||
216 | |||
217 | static int wafwdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused) | ||
218 | { | ||
219 | if (code == SYS_DOWN || code == SYS_HALT) { | ||
220 | /* Turn the WDT off */ | ||
221 | wafwdt_stop(); | ||
222 | } | ||
223 | return NOTIFY_DONE; | ||
224 | } | ||
225 | |||
226 | /* | ||
227 | * Kernel Interfaces | ||
228 | */ | ||
229 | |||
230 | static struct file_operations wafwdt_fops = { | ||
231 | .owner = THIS_MODULE, | ||
232 | .llseek = no_llseek, | ||
233 | .write = wafwdt_write, | ||
234 | .ioctl = wafwdt_ioctl, | ||
235 | .open = wafwdt_open, | ||
236 | .release = wafwdt_close, | ||
237 | }; | ||
238 | |||
239 | static struct miscdevice wafwdt_miscdev = { | ||
240 | .minor = WATCHDOG_MINOR, | ||
241 | .name = "watchdog", | ||
242 | .fops = &wafwdt_fops, | ||
243 | }; | ||
244 | |||
245 | /* | ||
246 | * The WDT needs to learn about soft shutdowns in order to | ||
247 | * turn the timebomb registers off. | ||
248 | */ | ||
249 | |||
250 | static struct notifier_block wafwdt_notifier = { | ||
251 | .notifier_call = wafwdt_notify_sys, | ||
252 | }; | ||
253 | |||
254 | static int __init wafwdt_init(void) | ||
255 | { | ||
256 | int ret; | ||
257 | |||
258 | printk(KERN_INFO "WDT driver for Wafer 5823 single board computer initialising.\n"); | ||
259 | |||
260 | spin_lock_init(&wafwdt_lock); | ||
261 | |||
262 | if (timeout < 1 || timeout > 255) { | ||
263 | timeout = WD_TIMO; | ||
264 | printk (KERN_INFO PFX "timeout value must be 1<=x<=255, using %d\n", | ||
265 | timeout); | ||
266 | } | ||
267 | |||
268 | if (wdt_stop != wdt_start) { | ||
269 | if(!request_region(wdt_stop, 1, "Wafer 5823 WDT")) { | ||
270 | printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", | ||
271 | wdt_stop); | ||
272 | ret = -EIO; | ||
273 | goto error; | ||
274 | } | ||
275 | } | ||
276 | |||
277 | if(!request_region(wdt_start, 1, "Wafer 5823 WDT")) { | ||
278 | printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", | ||
279 | wdt_start); | ||
280 | ret = -EIO; | ||
281 | goto error2; | ||
282 | } | ||
283 | |||
284 | ret = register_reboot_notifier(&wafwdt_notifier); | ||
285 | if (ret != 0) { | ||
286 | printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", | ||
287 | ret); | ||
288 | goto error3; | ||
289 | } | ||
290 | |||
291 | ret = misc_register(&wafwdt_miscdev); | ||
292 | if (ret != 0) { | ||
293 | printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | ||
294 | WATCHDOG_MINOR, ret); | ||
295 | goto error4; | ||
296 | } | ||
297 | |||
298 | printk (KERN_INFO PFX "initialized. timeout=%d sec (nowayout=%d)\n", | ||
299 | timeout, nowayout); | ||
300 | |||
301 | return ret; | ||
302 | error4: | ||
303 | unregister_reboot_notifier(&wafwdt_notifier); | ||
304 | error3: | ||
305 | release_region(wdt_start, 1); | ||
306 | error2: | ||
307 | if (wdt_stop != wdt_start) | ||
308 | release_region(wdt_stop, 1); | ||
309 | error: | ||
310 | return ret; | ||
311 | } | ||
312 | |||
313 | static void __exit wafwdt_exit(void) | ||
314 | { | ||
315 | misc_deregister(&wafwdt_miscdev); | ||
316 | unregister_reboot_notifier(&wafwdt_notifier); | ||
317 | if(wdt_stop != wdt_start) | ||
318 | release_region(wdt_stop, 1); | ||
319 | release_region(wdt_start, 1); | ||
320 | } | ||
321 | |||
322 | module_init(wafwdt_init); | ||
323 | module_exit(wafwdt_exit); | ||
324 | |||
325 | MODULE_AUTHOR("Justin Cormack"); | ||
326 | MODULE_DESCRIPTION("ICP Wafer 5823 Single Board Computer WDT driver"); | ||
327 | MODULE_LICENSE("GPL"); | ||
328 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||
329 | |||
330 | /* end of wafer5823wdt.c */ | ||