diff options
author | Wim Van Sebroeck <wim@iguana.be> | 2007-08-17 04:38:02 -0400 |
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committer | Wim Van Sebroeck <wim@iguana.be> | 2007-10-18 06:39:03 -0400 |
commit | b7e04f8c61a46d742de23af5d7ca2b41b33e40ac (patch) | |
tree | c52a7ea568648e2d8ed0d423098b42298de2058b /drivers/watchdog/scx200_wdt.c | |
parent | d85714d81cc0408daddb68c10f7fd69eafe7c213 (diff) |
mv watchdog tree under drivers
move watchdog tree from drivers/char/watchdog to drivers/watchdog.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog/scx200_wdt.c')
-rw-r--r-- | drivers/watchdog/scx200_wdt.c | 269 |
1 files changed, 269 insertions, 0 deletions
diff --git a/drivers/watchdog/scx200_wdt.c b/drivers/watchdog/scx200_wdt.c new file mode 100644 index 000000000000..d4fd0fa2f176 --- /dev/null +++ b/drivers/watchdog/scx200_wdt.c | |||
@@ -0,0 +1,269 @@ | |||
1 | /* drivers/char/watchdog/scx200_wdt.c | ||
2 | |||
3 | National Semiconductor SCx200 Watchdog support | ||
4 | |||
5 | Copyright (c) 2001,2002 Christer Weinigel <wingel@nano-system.com> | ||
6 | |||
7 | Some code taken from: | ||
8 | National Semiconductor PC87307/PC97307 (ala SC1200) WDT driver | ||
9 | (c) Copyright 2002 Zwane Mwaikambo <zwane@commfireservices.com> | ||
10 | |||
11 | This program is free software; you can redistribute it and/or | ||
12 | modify it under the terms of the GNU General Public License as | ||
13 | published by the Free Software Foundation; either version 2 of the | ||
14 | License, or (at your option) any later version. | ||
15 | |||
16 | The author(s) of this software shall not be held liable for damages | ||
17 | of any nature resulting due to the use of this software. This | ||
18 | software is provided AS-IS with no warranties. */ | ||
19 | |||
20 | #include <linux/module.h> | ||
21 | #include <linux/moduleparam.h> | ||
22 | #include <linux/init.h> | ||
23 | #include <linux/miscdevice.h> | ||
24 | #include <linux/watchdog.h> | ||
25 | #include <linux/notifier.h> | ||
26 | #include <linux/reboot.h> | ||
27 | #include <linux/fs.h> | ||
28 | #include <linux/ioport.h> | ||
29 | #include <linux/scx200.h> | ||
30 | |||
31 | #include <asm/uaccess.h> | ||
32 | #include <asm/io.h> | ||
33 | |||
34 | #define NAME "scx200_wdt" | ||
35 | |||
36 | MODULE_AUTHOR("Christer Weinigel <wingel@nano-system.com>"); | ||
37 | MODULE_DESCRIPTION("NatSemi SCx200 Watchdog Driver"); | ||
38 | MODULE_LICENSE("GPL"); | ||
39 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||
40 | |||
41 | static int margin = 60; /* in seconds */ | ||
42 | module_param(margin, int, 0); | ||
43 | MODULE_PARM_DESC(margin, "Watchdog margin in seconds"); | ||
44 | |||
45 | static int nowayout = WATCHDOG_NOWAYOUT; | ||
46 | module_param(nowayout, int, 0); | ||
47 | MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); | ||
48 | |||
49 | static u16 wdto_restart; | ||
50 | static struct semaphore open_semaphore; | ||
51 | static char expect_close; | ||
52 | |||
53 | /* Bits of the WDCNFG register */ | ||
54 | #define W_ENABLE 0x00fa /* Enable watchdog */ | ||
55 | #define W_DISABLE 0x0000 /* Disable watchdog */ | ||
56 | |||
57 | /* The scaling factor for the timer, this depends on the value of W_ENABLE */ | ||
58 | #define W_SCALE (32768/1024) | ||
59 | |||
60 | static void scx200_wdt_ping(void) | ||
61 | { | ||
62 | outw(wdto_restart, scx200_cb_base + SCx200_WDT_WDTO); | ||
63 | } | ||
64 | |||
65 | static void scx200_wdt_update_margin(void) | ||
66 | { | ||
67 | printk(KERN_INFO NAME ": timer margin %d seconds\n", margin); | ||
68 | wdto_restart = margin * W_SCALE; | ||
69 | } | ||
70 | |||
71 | static void scx200_wdt_enable(void) | ||
72 | { | ||
73 | printk(KERN_DEBUG NAME ": enabling watchdog timer, wdto_restart = %d\n", | ||
74 | wdto_restart); | ||
75 | |||
76 | outw(0, scx200_cb_base + SCx200_WDT_WDTO); | ||
77 | outb(SCx200_WDT_WDSTS_WDOVF, scx200_cb_base + SCx200_WDT_WDSTS); | ||
78 | outw(W_ENABLE, scx200_cb_base + SCx200_WDT_WDCNFG); | ||
79 | |||
80 | scx200_wdt_ping(); | ||
81 | } | ||
82 | |||
83 | static void scx200_wdt_disable(void) | ||
84 | { | ||
85 | printk(KERN_DEBUG NAME ": disabling watchdog timer\n"); | ||
86 | |||
87 | outw(0, scx200_cb_base + SCx200_WDT_WDTO); | ||
88 | outb(SCx200_WDT_WDSTS_WDOVF, scx200_cb_base + SCx200_WDT_WDSTS); | ||
89 | outw(W_DISABLE, scx200_cb_base + SCx200_WDT_WDCNFG); | ||
90 | } | ||
91 | |||
92 | static int scx200_wdt_open(struct inode *inode, struct file *file) | ||
93 | { | ||
94 | /* only allow one at a time */ | ||
95 | if (down_trylock(&open_semaphore)) | ||
96 | return -EBUSY; | ||
97 | scx200_wdt_enable(); | ||
98 | |||
99 | return nonseekable_open(inode, file); | ||
100 | } | ||
101 | |||
102 | static int scx200_wdt_release(struct inode *inode, struct file *file) | ||
103 | { | ||
104 | if (expect_close != 42) { | ||
105 | printk(KERN_WARNING NAME ": watchdog device closed unexpectedly, will not disable the watchdog timer\n"); | ||
106 | } else if (!nowayout) { | ||
107 | scx200_wdt_disable(); | ||
108 | } | ||
109 | expect_close = 0; | ||
110 | up(&open_semaphore); | ||
111 | |||
112 | return 0; | ||
113 | } | ||
114 | |||
115 | static int scx200_wdt_notify_sys(struct notifier_block *this, | ||
116 | unsigned long code, void *unused) | ||
117 | { | ||
118 | if (code == SYS_HALT || code == SYS_POWER_OFF) | ||
119 | if (!nowayout) | ||
120 | scx200_wdt_disable(); | ||
121 | |||
122 | return NOTIFY_DONE; | ||
123 | } | ||
124 | |||
125 | static struct notifier_block scx200_wdt_notifier = | ||
126 | { | ||
127 | .notifier_call = scx200_wdt_notify_sys, | ||
128 | }; | ||
129 | |||
130 | static ssize_t scx200_wdt_write(struct file *file, const char __user *data, | ||
131 | size_t len, loff_t *ppos) | ||
132 | { | ||
133 | /* check for a magic close character */ | ||
134 | if (len) | ||
135 | { | ||
136 | size_t i; | ||
137 | |||
138 | scx200_wdt_ping(); | ||
139 | |||
140 | expect_close = 0; | ||
141 | for (i = 0; i < len; ++i) { | ||
142 | char c; | ||
143 | if (get_user(c, data+i)) | ||
144 | return -EFAULT; | ||
145 | if (c == 'V') | ||
146 | expect_close = 42; | ||
147 | } | ||
148 | |||
149 | return len; | ||
150 | } | ||
151 | |||
152 | return 0; | ||
153 | } | ||
154 | |||
155 | static int scx200_wdt_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 | static struct watchdog_info ident = { | ||
161 | .identity = "NatSemi SCx200 Watchdog", | ||
162 | .firmware_version = 1, | ||
163 | .options = (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING), | ||
164 | }; | ||
165 | int new_margin; | ||
166 | |||
167 | switch (cmd) { | ||
168 | default: | ||
169 | return -ENOTTY; | ||
170 | case WDIOC_GETSUPPORT: | ||
171 | if(copy_to_user(argp, &ident, sizeof(ident))) | ||
172 | return -EFAULT; | ||
173 | return 0; | ||
174 | case WDIOC_GETSTATUS: | ||
175 | case WDIOC_GETBOOTSTATUS: | ||
176 | if (put_user(0, p)) | ||
177 | return -EFAULT; | ||
178 | return 0; | ||
179 | case WDIOC_KEEPALIVE: | ||
180 | scx200_wdt_ping(); | ||
181 | return 0; | ||
182 | case WDIOC_SETTIMEOUT: | ||
183 | if (get_user(new_margin, p)) | ||
184 | return -EFAULT; | ||
185 | if (new_margin < 1) | ||
186 | return -EINVAL; | ||
187 | margin = new_margin; | ||
188 | scx200_wdt_update_margin(); | ||
189 | scx200_wdt_ping(); | ||
190 | case WDIOC_GETTIMEOUT: | ||
191 | if (put_user(margin, p)) | ||
192 | return -EFAULT; | ||
193 | return 0; | ||
194 | } | ||
195 | } | ||
196 | |||
197 | static const struct file_operations scx200_wdt_fops = { | ||
198 | .owner = THIS_MODULE, | ||
199 | .llseek = no_llseek, | ||
200 | .write = scx200_wdt_write, | ||
201 | .ioctl = scx200_wdt_ioctl, | ||
202 | .open = scx200_wdt_open, | ||
203 | .release = scx200_wdt_release, | ||
204 | }; | ||
205 | |||
206 | static struct miscdevice scx200_wdt_miscdev = { | ||
207 | .minor = WATCHDOG_MINOR, | ||
208 | .name = "watchdog", | ||
209 | .fops = &scx200_wdt_fops, | ||
210 | }; | ||
211 | |||
212 | static int __init scx200_wdt_init(void) | ||
213 | { | ||
214 | int r; | ||
215 | |||
216 | printk(KERN_DEBUG NAME ": NatSemi SCx200 Watchdog Driver\n"); | ||
217 | |||
218 | /* check that we have found the configuration block */ | ||
219 | if (!scx200_cb_present()) | ||
220 | return -ENODEV; | ||
221 | |||
222 | if (!request_region(scx200_cb_base + SCx200_WDT_OFFSET, | ||
223 | SCx200_WDT_SIZE, | ||
224 | "NatSemi SCx200 Watchdog")) { | ||
225 | printk(KERN_WARNING NAME ": watchdog I/O region busy\n"); | ||
226 | return -EBUSY; | ||
227 | } | ||
228 | |||
229 | scx200_wdt_update_margin(); | ||
230 | scx200_wdt_disable(); | ||
231 | |||
232 | sema_init(&open_semaphore, 1); | ||
233 | |||
234 | r = misc_register(&scx200_wdt_miscdev); | ||
235 | if (r) { | ||
236 | release_region(scx200_cb_base + SCx200_WDT_OFFSET, | ||
237 | SCx200_WDT_SIZE); | ||
238 | return r; | ||
239 | } | ||
240 | |||
241 | r = register_reboot_notifier(&scx200_wdt_notifier); | ||
242 | if (r) { | ||
243 | printk(KERN_ERR NAME ": unable to register reboot notifier"); | ||
244 | misc_deregister(&scx200_wdt_miscdev); | ||
245 | release_region(scx200_cb_base + SCx200_WDT_OFFSET, | ||
246 | SCx200_WDT_SIZE); | ||
247 | return r; | ||
248 | } | ||
249 | |||
250 | return 0; | ||
251 | } | ||
252 | |||
253 | static void __exit scx200_wdt_cleanup(void) | ||
254 | { | ||
255 | unregister_reboot_notifier(&scx200_wdt_notifier); | ||
256 | misc_deregister(&scx200_wdt_miscdev); | ||
257 | release_region(scx200_cb_base + SCx200_WDT_OFFSET, | ||
258 | SCx200_WDT_SIZE); | ||
259 | } | ||
260 | |||
261 | module_init(scx200_wdt_init); | ||
262 | module_exit(scx200_wdt_cleanup); | ||
263 | |||
264 | /* | ||
265 | Local variables: | ||
266 | compile-command: "make -k -C ../.. SUBDIRS=drivers/char modules" | ||
267 | c-basic-offset: 8 | ||
268 | End: | ||
269 | */ | ||