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> | |
b10958d3 WVS |
32 | * - added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT |
33 | * | |
34 | * Version 0.6 (2002/04/12): Rob Radez <rob@osinvestor.com> | |
35 | * - make mixcomwd_opened unsigned, | |
36 | * removed lock_kernel/unlock_kernel from mixcomwd_release, | |
37 | * modified ioctl a bit to conform to API | |
1da177e4 LT |
38 | * |
39 | */ | |
40 | ||
b10958d3 | 41 | #define VERSION "0.6" |
1da177e4 LT |
42 | |
43 | #include <linux/module.h> | |
44 | #include <linux/moduleparam.h> | |
1da177e4 LT |
45 | #include <linux/types.h> |
46 | #include <linux/miscdevice.h> | |
47 | #include <linux/ioport.h> | |
48 | #include <linux/watchdog.h> | |
49 | #include <linux/fs.h> | |
50 | #include <linux/reboot.h> | |
51 | #include <linux/init.h> | |
4e57b681 TS |
52 | #include <linux/jiffies.h> |
53 | #include <linux/timer.h> | |
1da177e4 LT |
54 | #include <asm/uaccess.h> |
55 | #include <asm/io.h> | |
56 | ||
57 | static int mixcomwd_ioports[] = { 0x180, 0x280, 0x380, 0x000 }; | |
58 | ||
59 | #define MIXCOM_WATCHDOG_OFFSET 0xc10 | |
60 | #define MIXCOM_ID 0x11 | |
61 | #define FLASHCOM_WATCHDOG_OFFSET 0x4 | |
62 | #define FLASHCOM_ID 0x18 | |
63 | ||
82eb7c50 JS |
64 | static void mixcomwd_timerfun(unsigned long d); |
65 | ||
1da177e4 LT |
66 | static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */ |
67 | ||
68 | static int watchdog_port; | |
69 | static int mixcomwd_timer_alive; | |
82eb7c50 | 70 | static DEFINE_TIMER(mixcomwd_timer, mixcomwd_timerfun, 0, 0); |
1da177e4 LT |
71 | static char expect_close; |
72 | ||
4bfdf378 | 73 | static int nowayout = WATCHDOG_NOWAYOUT; |
1da177e4 | 74 | module_param(nowayout, int, 0); |
bffda5c8 | 75 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |
1da177e4 LT |
76 | |
77 | static void mixcomwd_ping(void) | |
78 | { | |
79 | outb_p(55,watchdog_port); | |
80 | return; | |
81 | } | |
82 | ||
83 | static void mixcomwd_timerfun(unsigned long d) | |
84 | { | |
85 | mixcomwd_ping(); | |
86 | ||
82eb7c50 | 87 | mod_timer(&mixcomwd_timer, jiffies + 5 * HZ); |
1da177e4 LT |
88 | } |
89 | ||
90 | /* | |
91 | * Allow only one person to hold it open | |
92 | */ | |
93 | ||
94 | static int mixcomwd_open(struct inode *inode, struct file *file) | |
95 | { | |
96 | if(test_and_set_bit(0,&mixcomwd_opened)) { | |
97 | return -EBUSY; | |
98 | } | |
99 | mixcomwd_ping(); | |
100 | ||
101 | if (nowayout) { | |
102 | /* | |
103 | * fops_get() code via open() has already done | |
104 | * a try_module_get() so it is safe to do the | |
105 | * __module_get(). | |
106 | */ | |
107 | __module_get(THIS_MODULE); | |
108 | } else { | |
109 | if(mixcomwd_timer_alive) { | |
110 | del_timer(&mixcomwd_timer); | |
111 | mixcomwd_timer_alive=0; | |
112 | } | |
113 | } | |
114 | return nonseekable_open(inode, file); | |
115 | } | |
116 | ||
117 | static int mixcomwd_release(struct inode *inode, struct file *file) | |
118 | { | |
119 | if (expect_close == 42) { | |
120 | if(mixcomwd_timer_alive) { | |
121 | printk(KERN_ERR "mixcomwd: release called while internal timer alive"); | |
122 | return -EBUSY; | |
123 | } | |
1da177e4 | 124 | mixcomwd_timer_alive=1; |
82eb7c50 | 125 | mod_timer(&mixcomwd_timer, jiffies + 5 * HZ); |
1da177e4 LT |
126 | } else { |
127 | printk(KERN_CRIT "mixcomwd: WDT device closed unexpectedly. WDT will not stop!\n"); | |
128 | } | |
129 | ||
130 | clear_bit(0,&mixcomwd_opened); | |
131 | expect_close=0; | |
132 | return 0; | |
133 | } | |
134 | ||
135 | ||
136 | static ssize_t mixcomwd_write(struct file *file, const char __user *data, size_t len, loff_t *ppos) | |
137 | { | |
138 | if(len) | |
139 | { | |
140 | if (!nowayout) { | |
141 | size_t i; | |
142 | ||
143 | /* In case it was set long ago */ | |
144 | expect_close = 0; | |
145 | ||
146 | for (i = 0; i != len; i++) { | |
147 | char c; | |
148 | if (get_user(c, data + i)) | |
149 | return -EFAULT; | |
150 | if (c == 'V') | |
151 | expect_close = 42; | |
152 | } | |
153 | } | |
154 | mixcomwd_ping(); | |
155 | } | |
156 | return len; | |
157 | } | |
158 | ||
159 | static int mixcomwd_ioctl(struct inode *inode, struct file *file, | |
160 | unsigned int cmd, unsigned long arg) | |
161 | { | |
162 | void __user *argp = (void __user *)arg; | |
163 | int __user *p = argp; | |
164 | int status; | |
165 | static struct watchdog_info ident = { | |
166 | .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, | |
167 | .firmware_version = 1, | |
168 | .identity = "MixCOM watchdog", | |
169 | }; | |
170 | ||
171 | switch(cmd) | |
172 | { | |
173 | case WDIOC_GETSTATUS: | |
174 | status=mixcomwd_opened; | |
175 | if (!nowayout) { | |
176 | status|=mixcomwd_timer_alive; | |
177 | } | |
178 | if (copy_to_user(p, &status, sizeof(int))) { | |
179 | return -EFAULT; | |
180 | } | |
181 | break; | |
182 | case WDIOC_GETSUPPORT: | |
183 | if (copy_to_user(argp, &ident, sizeof(ident))) { | |
184 | return -EFAULT; | |
185 | } | |
186 | break; | |
187 | case WDIOC_KEEPALIVE: | |
188 | mixcomwd_ping(); | |
189 | break; | |
190 | default: | |
795b89d2 | 191 | return -ENOTTY; |
1da177e4 LT |
192 | } |
193 | return 0; | |
194 | } | |
195 | ||
62322d25 | 196 | static const struct file_operations mixcomwd_fops= |
1da177e4 LT |
197 | { |
198 | .owner = THIS_MODULE, | |
199 | .llseek = no_llseek, | |
200 | .write = mixcomwd_write, | |
201 | .ioctl = mixcomwd_ioctl, | |
202 | .open = mixcomwd_open, | |
203 | .release = mixcomwd_release, | |
204 | }; | |
205 | ||
206 | static struct miscdevice mixcomwd_miscdev= | |
207 | { | |
208 | .minor = WATCHDOG_MINOR, | |
209 | .name = "watchdog", | |
210 | .fops = &mixcomwd_fops, | |
211 | }; | |
212 | ||
213 | static int __init mixcomwd_checkcard(int port) | |
214 | { | |
215 | int id; | |
216 | ||
217 | port += MIXCOM_WATCHDOG_OFFSET; | |
218 | if (!request_region(port, 1, "MixCOM watchdog")) { | |
219 | return 0; | |
220 | } | |
221 | ||
222 | id=inb_p(port) & 0x3f; | |
223 | if(id!=MIXCOM_ID) { | |
224 | release_region(port, 1); | |
225 | return 0; | |
226 | } | |
227 | return port; | |
228 | } | |
229 | ||
230 | static int __init flashcom_checkcard(int port) | |
231 | { | |
232 | int id; | |
233 | ||
234 | port += FLASHCOM_WATCHDOG_OFFSET; | |
235 | if (!request_region(port, 1, "MixCOM watchdog")) { | |
236 | return 0; | |
237 | } | |
238 | ||
239 | id=inb_p(port); | |
240 | if(id!=FLASHCOM_ID) { | |
241 | release_region(port, 1); | |
242 | return 0; | |
243 | } | |
244 | return port; | |
245 | } | |
246 | ||
247 | static int __init mixcomwd_init(void) | |
248 | { | |
249 | int i; | |
250 | int ret; | |
251 | int found=0; | |
252 | ||
253 | for (i = 0; !found && mixcomwd_ioports[i] != 0; i++) { | |
254 | watchdog_port = mixcomwd_checkcard(mixcomwd_ioports[i]); | |
255 | if (watchdog_port) { | |
256 | found = 1; | |
257 | } | |
258 | } | |
259 | ||
260 | /* The FlashCOM card can be set up at 0x300 -> 0x378, in 0x8 jumps */ | |
261 | for (i = 0x300; !found && i < 0x380; i+=0x8) { | |
262 | watchdog_port = flashcom_checkcard(i); | |
263 | if (watchdog_port) { | |
264 | found = 1; | |
265 | } | |
266 | } | |
267 | ||
268 | if (!found) { | |
269 | printk("mixcomwd: No card detected, or port not available.\n"); | |
270 | return -ENODEV; | |
271 | } | |
272 | ||
273 | ret = misc_register(&mixcomwd_miscdev); | |
274 | if (ret) | |
275 | { | |
276 | release_region(watchdog_port, 1); | |
277 | return ret; | |
278 | } | |
279 | ||
280 | printk(KERN_INFO "MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",VERSION,watchdog_port); | |
281 | ||
282 | return 0; | |
283 | } | |
284 | ||
285 | static void __exit mixcomwd_exit(void) | |
286 | { | |
287 | if (!nowayout) { | |
288 | if(mixcomwd_timer_alive) { | |
289 | printk(KERN_WARNING "mixcomwd: I quit now, hardware will" | |
290 | " probably reboot!\n"); | |
82eb7c50 | 291 | del_timer_sync(&mixcomwd_timer); |
1da177e4 LT |
292 | mixcomwd_timer_alive=0; |
293 | } | |
294 | } | |
295 | release_region(watchdog_port,1); | |
296 | misc_deregister(&mixcomwd_miscdev); | |
297 | } | |
298 | ||
299 | module_init(mixcomwd_init); | |
300 | module_exit(mixcomwd_exit); | |
301 | ||
302 | MODULE_AUTHOR("Gergely Madarasz <gorgo@itc.hu>"); | |
303 | MODULE_DESCRIPTION("MixCom Watchdog driver"); | |
304 | MODULE_LICENSE("GPL"); | |
305 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |