diff options
Diffstat (limited to 'drivers/char/watchdog/indydog.c')
-rw-r--r-- | drivers/char/watchdog/indydog.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/drivers/char/watchdog/indydog.c b/drivers/char/watchdog/indydog.c new file mode 100644 index 000000000000..6af2c799b57e --- /dev/null +++ b/drivers/char/watchdog/indydog.c | |||
@@ -0,0 +1,221 @@ | |||
1 | /* | ||
2 | * IndyDog 0.3 A Hardware Watchdog Device for SGI IP22 | ||
3 | * | ||
4 | * (c) Copyright 2002 Guido Guenther <agx@sigxcpu.org>, All Rights Reserved. | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or | ||
7 | * modify it under the terms of the GNU General Public License | ||
8 | * as published by the Free Software Foundation; either version | ||
9 | * 2 of the License, or (at your option) any later version. | ||
10 | * | ||
11 | * based on softdog.c by Alan Cox <alan@redhat.com> | ||
12 | */ | ||
13 | |||
14 | #include <linux/module.h> | ||
15 | #include <linux/moduleparam.h> | ||
16 | #include <linux/config.h> | ||
17 | #include <linux/types.h> | ||
18 | #include <linux/kernel.h> | ||
19 | #include <linux/fs.h> | ||
20 | #include <linux/mm.h> | ||
21 | #include <linux/miscdevice.h> | ||
22 | #include <linux/watchdog.h> | ||
23 | #include <linux/notifier.h> | ||
24 | #include <linux/reboot.h> | ||
25 | #include <linux/init.h> | ||
26 | #include <asm/uaccess.h> | ||
27 | #include <asm/sgi/mc.h> | ||
28 | |||
29 | #define PFX "indydog: " | ||
30 | static int indydog_alive; | ||
31 | |||
32 | #ifdef CONFIG_WATCHDOG_NOWAYOUT | ||
33 | static int nowayout = 1; | ||
34 | #else | ||
35 | static int nowayout = 0; | ||
36 | #endif | ||
37 | |||
38 | #define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */ | ||
39 | |||
40 | module_param(nowayout, int, 0); | ||
41 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); | ||
42 | |||
43 | static void indydog_start(void) | ||
44 | { | ||
45 | u32 mc_ctrl0 = sgimc->cpuctrl0; | ||
46 | |||
47 | mc_ctrl0 = sgimc->cpuctrl0 | SGIMC_CCTRL0_WDOG; | ||
48 | sgimc->cpuctrl0 = mc_ctrl0; | ||
49 | } | ||
50 | |||
51 | static void indydog_stop(void) | ||
52 | { | ||
53 | u32 mc_ctrl0 = sgimc->cpuctrl0; | ||
54 | |||
55 | mc_ctrl0 &= ~SGIMC_CCTRL0_WDOG; | ||
56 | sgimc->cpuctrl0 = mc_ctrl0; | ||
57 | |||
58 | printk(KERN_INFO PFX "Stopped watchdog timer.\n"); | ||
59 | } | ||
60 | |||
61 | static void indydog_ping(void) | ||
62 | { | ||
63 | sgimc->watchdogt = 0; | ||
64 | } | ||
65 | |||
66 | /* | ||
67 | * Allow only one person to hold it open | ||
68 | */ | ||
69 | static int indydog_open(struct inode *inode, struct file *file) | ||
70 | { | ||
71 | if (indydog_alive) | ||
72 | return -EBUSY; | ||
73 | |||
74 | if (nowayout) | ||
75 | __module_get(THIS_MODULE); | ||
76 | |||
77 | /* Activate timer */ | ||
78 | indydog_start(); | ||
79 | indydog_ping(); | ||
80 | |||
81 | indydog_alive = 1; | ||
82 | printk(KERN_INFO "Started watchdog timer.\n"); | ||
83 | |||
84 | return nonseekable_open(inode, file); | ||
85 | } | ||
86 | |||
87 | static int indydog_release(struct inode *inode, struct file *file) | ||
88 | { | ||
89 | /* Shut off the timer. | ||
90 | * Lock it in if it's a module and we defined ...NOWAYOUT */ | ||
91 | if (!nowayout) | ||
92 | indydog_stop(); /* Turn the WDT off */ | ||
93 | |||
94 | indydog_alive = 0; | ||
95 | |||
96 | return 0; | ||
97 | } | ||
98 | |||
99 | static ssize_t indydog_write(struct file *file, const char *data, size_t len, loff_t *ppos) | ||
100 | { | ||
101 | /* Refresh the timer. */ | ||
102 | if (len) { | ||
103 | indydog_ping(); | ||
104 | } | ||
105 | return len; | ||
106 | } | ||
107 | |||
108 | static int indydog_ioctl(struct inode *inode, struct file *file, | ||
109 | unsigned int cmd, unsigned long arg) | ||
110 | { | ||
111 | int options, retval = -EINVAL; | ||
112 | static struct watchdog_info ident = { | ||
113 | .options = WDIOF_KEEPALIVEPING | | ||
114 | WDIOF_MAGICCLOSE, | ||
115 | .firmware_version = 0, | ||
116 | .identity = "Hardware Watchdog for SGI IP22", | ||
117 | }; | ||
118 | |||
119 | switch (cmd) { | ||
120 | default: | ||
121 | return -ENOIOCTLCMD; | ||
122 | case WDIOC_GETSUPPORT: | ||
123 | if (copy_to_user((struct watchdog_info *)arg, | ||
124 | &ident, sizeof(ident))) | ||
125 | return -EFAULT; | ||
126 | return 0; | ||
127 | case WDIOC_GETSTATUS: | ||
128 | case WDIOC_GETBOOTSTATUS: | ||
129 | return put_user(0,(int *)arg); | ||
130 | case WDIOC_KEEPALIVE: | ||
131 | indydog_ping(); | ||
132 | return 0; | ||
133 | case WDIOC_GETTIMEOUT: | ||
134 | return put_user(WATCHDOG_TIMEOUT,(int *)arg); | ||
135 | case WDIOC_SETOPTIONS: | ||
136 | { | ||
137 | if (get_user(options, (int *)arg)) | ||
138 | return -EFAULT; | ||
139 | |||
140 | if (options & WDIOS_DISABLECARD) { | ||
141 | indydog_stop(); | ||
142 | retval = 0; | ||
143 | } | ||
144 | |||
145 | if (options & WDIOS_ENABLECARD) { | ||
146 | indydog_start(); | ||
147 | retval = 0; | ||
148 | } | ||
149 | |||
150 | return retval; | ||
151 | } | ||
152 | } | ||
153 | } | ||
154 | |||
155 | static int indydog_notify_sys(struct notifier_block *this, unsigned long code, void *unused) | ||
156 | { | ||
157 | if (code == SYS_DOWN || code == SYS_HALT) | ||
158 | indydog_stop(); /* Turn the WDT off */ | ||
159 | |||
160 | return NOTIFY_DONE; | ||
161 | } | ||
162 | |||
163 | static struct file_operations indydog_fops = { | ||
164 | .owner = THIS_MODULE, | ||
165 | .llseek = no_llseek, | ||
166 | .write = indydog_write, | ||
167 | .ioctl = indydog_ioctl, | ||
168 | .open = indydog_open, | ||
169 | .release = indydog_release, | ||
170 | }; | ||
171 | |||
172 | static struct miscdevice indydog_miscdev = { | ||
173 | .minor = WATCHDOG_MINOR, | ||
174 | .name = "watchdog", | ||
175 | .fops = &indydog_fops, | ||
176 | }; | ||
177 | |||
178 | static struct notifier_block indydog_notifier = { | ||
179 | .notifier_call = indydog_notify_sys, | ||
180 | }; | ||
181 | |||
182 | static char banner[] __initdata = | ||
183 | KERN_INFO PFX "Hardware Watchdog Timer for SGI IP22: 0.3\n"; | ||
184 | |||
185 | static int __init watchdog_init(void) | ||
186 | { | ||
187 | int ret; | ||
188 | |||
189 | ret = register_reboot_notifier(&indydog_notifier); | ||
190 | if (ret) { | ||
191 | printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", | ||
192 | ret); | ||
193 | return ret; | ||
194 | } | ||
195 | |||
196 | ret = misc_register(&indydog_miscdev); | ||
197 | if (ret) { | ||
198 | printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", | ||
199 | WATCHDOG_MINOR, ret); | ||
200 | unregister_reboot_notifier(&indydog_notifier); | ||
201 | return ret; | ||
202 | } | ||
203 | |||
204 | printk(banner); | ||
205 | |||
206 | return 0; | ||
207 | } | ||
208 | |||
209 | static void __exit watchdog_exit(void) | ||
210 | { | ||
211 | misc_deregister(&indydog_miscdev); | ||
212 | unregister_reboot_notifier(&indydog_notifier); | ||
213 | } | ||
214 | |||
215 | module_init(watchdog_init); | ||
216 | module_exit(watchdog_exit); | ||
217 | |||
218 | MODULE_AUTHOR("Guido Guenther <agx@sigxcpu.org>"); | ||
219 | MODULE_DESCRIPTION("Hardware Watchdog Device for SGI IP22"); | ||
220 | MODULE_LICENSE("GPL"); | ||
221 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||