Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * MixCom Watchdog: A Simple Hardware Watchdog Device | |
3 | * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis | |
4 | * | |
5 | * Author: Gergely Madarasz <gorgo@itc.hu> | |
6 | * | |
7 | * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu> | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or | |
10 | * modify it under the terms of the GNU General Public License | |
11 | * as published by the Free Software Foundation; either version | |
12 | * 2 of the License, or (at your option) any later version. | |
13 | * | |
14 | * Version 0.1 (99/04/15): | |
15 | * - first version | |
16 | * | |
17 | * Version 0.2 (99/06/16): | |
18 | * - added kernel timer watchdog ping after close | |
19 | * since the hardware does not support watchdog shutdown | |
20 | * | |
21 | * Version 0.3 (99/06/21): | |
22 | * - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls | |
23 | * | |
24 | * Version 0.3.1 (99/06/22): | |
25 | * - allow module removal while internal timer is active, | |
26 | * print warning about probable reset | |
27 | * | |
28 | * Version 0.4 (99/11/15): | |
29 | * - support for one more type board | |
30 | * | |
31 | * Version 0.5 (2001/12/14) Matt Domsch <Matt_Domsch@dell.com> | |
32 | * - added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT | |
33 | * | |
34 | */ | |
35 | ||
36 | #define VERSION "0.5" | |
37 | ||
38 | #include <linux/module.h> | |
39 | #include <linux/moduleparam.h> | |
40 | #include <linux/config.h> | |
41 | #include <linux/types.h> | |
42 | #include <linux/miscdevice.h> | |
43 | #include <linux/ioport.h> | |
44 | #include <linux/watchdog.h> | |
45 | #include <linux/fs.h> | |
46 | #include <linux/reboot.h> | |
47 | #include <linux/init.h> | |
48 | #include <asm/uaccess.h> | |
49 | #include <asm/io.h> | |
50 | ||
51 | static int mixcomwd_ioports[] = { 0x180, 0x280, 0x380, 0x000 }; | |
52 | ||
53 | #define MIXCOM_WATCHDOG_OFFSET 0xc10 | |
54 | #define MIXCOM_ID 0x11 | |
55 | #define FLASHCOM_WATCHDOG_OFFSET 0x4 | |
56 | #define FLASHCOM_ID 0x18 | |
57 | ||
58 | static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */ | |
59 | ||
60 | static int watchdog_port; | |
61 | static int mixcomwd_timer_alive; | |
8d06afab | 62 | static DEFINE_TIMER(mixcomwd_timer, NULL, 0, 0); |
1da177e4 LT |
63 | static char expect_close; |
64 | ||
4bfdf378 | 65 | static int nowayout = WATCHDOG_NOWAYOUT; |
1da177e4 LT |
66 | module_param(nowayout, int, 0); |
67 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); | |
68 | ||
69 | static void mixcomwd_ping(void) | |
70 | { | |
71 | outb_p(55,watchdog_port); | |
72 | return; | |
73 | } | |
74 | ||
75 | static void mixcomwd_timerfun(unsigned long d) | |
76 | { | |
77 | mixcomwd_ping(); | |
78 | ||
79 | mod_timer(&mixcomwd_timer,jiffies+ 5*HZ); | |
80 | } | |
81 | ||
82 | /* | |
83 | * Allow only one person to hold it open | |
84 | */ | |
85 | ||
86 | static int mixcomwd_open(struct inode *inode, struct file *file) | |
87 | { | |
88 | if(test_and_set_bit(0,&mixcomwd_opened)) { | |
89 | return -EBUSY; | |
90 | } | |
91 | mixcomwd_ping(); | |
92 | ||
93 | if (nowayout) { | |
94 | /* | |
95 | * fops_get() code via open() has already done | |
96 | * a try_module_get() so it is safe to do the | |
97 | * __module_get(). | |
98 | */ | |
99 | __module_get(THIS_MODULE); | |
100 | } else { | |
101 | if(mixcomwd_timer_alive) { | |
102 | del_timer(&mixcomwd_timer); | |
103 | mixcomwd_timer_alive=0; | |
104 | } | |
105 | } | |
106 | return nonseekable_open(inode, file); | |
107 | } | |
108 | ||
109 | static int mixcomwd_release(struct inode *inode, struct file *file) | |
110 | { | |
111 | if (expect_close == 42) { | |
112 | if(mixcomwd_timer_alive) { | |
113 | printk(KERN_ERR "mixcomwd: release called while internal timer alive"); | |
114 | return -EBUSY; | |
115 | } | |
116 | init_timer(&mixcomwd_timer); | |
117 | mixcomwd_timer.expires=jiffies + 5 * HZ; | |
118 | mixcomwd_timer.function=mixcomwd_timerfun; | |
119 | mixcomwd_timer.data=0; | |
120 | mixcomwd_timer_alive=1; | |
121 | add_timer(&mixcomwd_timer); | |
122 | } else { | |
123 | printk(KERN_CRIT "mixcomwd: WDT device closed unexpectedly. WDT will not stop!\n"); | |
124 | } | |
125 | ||
126 | clear_bit(0,&mixcomwd_opened); | |
127 | expect_close=0; | |
128 | return 0; | |
129 | } | |
130 | ||
131 | ||
132 | static ssize_t mixcomwd_write(struct file *file, const char __user *data, size_t len, loff_t *ppos) | |
133 | { | |
134 | if(len) | |
135 | { | |
136 | if (!nowayout) { | |
137 | size_t i; | |
138 | ||
139 | /* In case it was set long ago */ | |
140 | expect_close = 0; | |
141 | ||
142 | for (i = 0; i != len; i++) { | |
143 | char c; | |
144 | if (get_user(c, data + i)) | |
145 | return -EFAULT; | |
146 | if (c == 'V') | |
147 | expect_close = 42; | |
148 | } | |
149 | } | |
150 | mixcomwd_ping(); | |
151 | } | |
152 | return len; | |
153 | } | |
154 | ||
155 | static int mixcomwd_ioctl(struct inode *inode, struct file *file, | |
156 | unsigned int cmd, unsigned long arg) | |
157 | { | |
158 | void __user *argp = (void __user *)arg; | |
159 | int __user *p = argp; | |
160 | int status; | |
161 | static struct watchdog_info ident = { | |
162 | .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, | |
163 | .firmware_version = 1, | |
164 | .identity = "MixCOM watchdog", | |
165 | }; | |
166 | ||
167 | switch(cmd) | |
168 | { | |
169 | case WDIOC_GETSTATUS: | |
170 | status=mixcomwd_opened; | |
171 | if (!nowayout) { | |
172 | status|=mixcomwd_timer_alive; | |
173 | } | |
174 | if (copy_to_user(p, &status, sizeof(int))) { | |
175 | return -EFAULT; | |
176 | } | |
177 | break; | |
178 | case WDIOC_GETSUPPORT: | |
179 | if (copy_to_user(argp, &ident, sizeof(ident))) { | |
180 | return -EFAULT; | |
181 | } | |
182 | break; | |
183 | case WDIOC_KEEPALIVE: | |
184 | mixcomwd_ping(); | |
185 | break; | |
186 | default: | |
187 | return -ENOIOCTLCMD; | |
188 | } | |
189 | return 0; | |
190 | } | |
191 | ||
192 | static struct file_operations mixcomwd_fops= | |
193 | { | |
194 | .owner = THIS_MODULE, | |
195 | .llseek = no_llseek, | |
196 | .write = mixcomwd_write, | |
197 | .ioctl = mixcomwd_ioctl, | |
198 | .open = mixcomwd_open, | |
199 | .release = mixcomwd_release, | |
200 | }; | |
201 | ||
202 | static struct miscdevice mixcomwd_miscdev= | |
203 | { | |
204 | .minor = WATCHDOG_MINOR, | |
205 | .name = "watchdog", | |
206 | .fops = &mixcomwd_fops, | |
207 | }; | |
208 | ||
209 | static int __init mixcomwd_checkcard(int port) | |
210 | { | |
211 | int id; | |
212 | ||
213 | port += MIXCOM_WATCHDOG_OFFSET; | |
214 | if (!request_region(port, 1, "MixCOM watchdog")) { | |
215 | return 0; | |
216 | } | |
217 | ||
218 | id=inb_p(port) & 0x3f; | |
219 | if(id!=MIXCOM_ID) { | |
220 | release_region(port, 1); | |
221 | return 0; | |
222 | } | |
223 | return port; | |
224 | } | |
225 | ||
226 | static int __init flashcom_checkcard(int port) | |
227 | { | |
228 | int id; | |
229 | ||
230 | port += FLASHCOM_WATCHDOG_OFFSET; | |
231 | if (!request_region(port, 1, "MixCOM watchdog")) { | |
232 | return 0; | |
233 | } | |
234 | ||
235 | id=inb_p(port); | |
236 | if(id!=FLASHCOM_ID) { | |
237 | release_region(port, 1); | |
238 | return 0; | |
239 | } | |
240 | return port; | |
241 | } | |
242 | ||
243 | static int __init mixcomwd_init(void) | |
244 | { | |
245 | int i; | |
246 | int ret; | |
247 | int found=0; | |
248 | ||
249 | for (i = 0; !found && mixcomwd_ioports[i] != 0; i++) { | |
250 | watchdog_port = mixcomwd_checkcard(mixcomwd_ioports[i]); | |
251 | if (watchdog_port) { | |
252 | found = 1; | |
253 | } | |
254 | } | |
255 | ||
256 | /* The FlashCOM card can be set up at 0x300 -> 0x378, in 0x8 jumps */ | |
257 | for (i = 0x300; !found && i < 0x380; i+=0x8) { | |
258 | watchdog_port = flashcom_checkcard(i); | |
259 | if (watchdog_port) { | |
260 | found = 1; | |
261 | } | |
262 | } | |
263 | ||
264 | if (!found) { | |
265 | printk("mixcomwd: No card detected, or port not available.\n"); | |
266 | return -ENODEV; | |
267 | } | |
268 | ||
269 | ret = misc_register(&mixcomwd_miscdev); | |
270 | if (ret) | |
271 | { | |
272 | release_region(watchdog_port, 1); | |
273 | return ret; | |
274 | } | |
275 | ||
276 | printk(KERN_INFO "MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",VERSION,watchdog_port); | |
277 | ||
278 | return 0; | |
279 | } | |
280 | ||
281 | static void __exit mixcomwd_exit(void) | |
282 | { | |
283 | if (!nowayout) { | |
284 | if(mixcomwd_timer_alive) { | |
285 | printk(KERN_WARNING "mixcomwd: I quit now, hardware will" | |
286 | " probably reboot!\n"); | |
287 | del_timer(&mixcomwd_timer); | |
288 | mixcomwd_timer_alive=0; | |
289 | } | |
290 | } | |
291 | release_region(watchdog_port,1); | |
292 | misc_deregister(&mixcomwd_miscdev); | |
293 | } | |
294 | ||
295 | module_init(mixcomwd_init); | |
296 | module_exit(mixcomwd_exit); | |
297 | ||
298 | MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>"); | |
299 | MODULE_DESCRIPTION("MixCom Watchdog driver"); | |
300 | MODULE_LICENSE("GPL"); | |
301 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |