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/wdt285.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/wdt285.c')
-rw-r--r-- | drivers/char/watchdog/wdt285.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/drivers/char/watchdog/wdt285.c b/drivers/char/watchdog/wdt285.c new file mode 100644 index 000000000000..52825a1f1779 --- /dev/null +++ b/drivers/char/watchdog/wdt285.c | |||
@@ -0,0 +1,229 @@ | |||
1 | /* | ||
2 | * Intel 21285 watchdog driver | ||
3 | * Copyright (c) Phil Blundell <pb@nexus.co.uk>, 1998 | ||
4 | * | ||
5 | * based on | ||
6 | * | ||
7 | * SoftDog 0.05: A Software Watchdog Device | ||
8 | * | ||
9 | * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved. | ||
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 | ||
13 | * as published by the Free Software Foundation; either version | ||
14 | * 2 of the License, or (at your option) any later version. | ||
15 | * | ||
16 | */ | ||
17 | |||
18 | #include <linux/module.h> | ||
19 | #include <linux/moduleparam.h> | ||
20 | #include <linux/types.h> | ||
21 | #include <linux/kernel.h> | ||
22 | #include <linux/fs.h> | ||
23 | #include <linux/mm.h> | ||
24 | #include <linux/miscdevice.h> | ||
25 | #include <linux/watchdog.h> | ||
26 | #include <linux/reboot.h> | ||
27 | #include <linux/init.h> | ||
28 | #include <linux/interrupt.h> | ||
29 | |||
30 | #include <asm/irq.h> | ||
31 | #include <asm/uaccess.h> | ||
32 | #include <asm/hardware.h> | ||
33 | #include <asm/mach-types.h> | ||
34 | #include <asm/hardware/dec21285.h> | ||
35 | |||
36 | /* | ||
37 | * Define this to stop the watchdog actually rebooting the machine. | ||
38 | */ | ||
39 | #undef ONLY_TESTING | ||
40 | |||
41 | static unsigned int soft_margin = 60; /* in seconds */ | ||
42 | static unsigned int reload; | ||
43 | static unsigned long timer_alive; | ||
44 | |||
45 | #ifdef ONLY_TESTING | ||
46 | /* | ||
47 | * If the timer expires.. | ||
48 | */ | ||
49 | static void watchdog_fire(int irq, void *dev_id, struct pt_regs *regs) | ||
50 | { | ||
51 | printk(KERN_CRIT "Watchdog: Would Reboot.\n"); | ||
52 | *CSR_TIMER4_CNTL = 0; | ||
53 | *CSR_TIMER4_CLR = 0; | ||
54 | } | ||
55 | #endif | ||
56 | |||
57 | /* | ||
58 | * Refresh the timer. | ||
59 | */ | ||
60 | static void watchdog_ping(void) | ||
61 | { | ||
62 | *CSR_TIMER4_LOAD = reload; | ||
63 | } | ||
64 | |||
65 | /* | ||
66 | * Allow only one person to hold it open | ||
67 | */ | ||
68 | static int watchdog_open(struct inode *inode, struct file *file) | ||
69 | { | ||
70 | int ret; | ||
71 | |||
72 | if (*CSR_SA110_CNTL & (1 << 13)) | ||
73 | return -EBUSY; | ||
74 | |||
75 | if (test_and_set_bit(1, &timer_alive)) | ||
76 | return -EBUSY; | ||
77 | |||
78 | reload = soft_margin * (mem_fclk_21285 / 256); | ||
79 | |||
80 | *CSR_TIMER4_CLR = 0; | ||
81 | watchdog_ping(); | ||
82 | *CSR_TIMER4_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD | ||
83 | | TIMER_CNTL_DIV256; | ||
84 | |||
85 | #ifdef ONLY_TESTING | ||
86 | ret = request_irq(IRQ_TIMER4, watchdog_fire, 0, "watchdog", NULL); | ||
87 | if (ret) { | ||
88 | *CSR_TIMER4_CNTL = 0; | ||
89 | clear_bit(1, &timer_alive); | ||
90 | } | ||
91 | #else | ||
92 | /* | ||
93 | * Setting this bit is irreversible; once enabled, there is | ||
94 | * no way to disable the watchdog. | ||
95 | */ | ||
96 | *CSR_SA110_CNTL |= 1 << 13; | ||
97 | |||
98 | ret = 0; | ||
99 | #endif | ||
100 | nonseekable_open(inode, file); | ||
101 | return ret; | ||
102 | } | ||
103 | |||
104 | /* | ||
105 | * Shut off the timer. | ||
106 | * Note: if we really have enabled the watchdog, there | ||
107 | * is no way to turn off. | ||
108 | */ | ||
109 | static int watchdog_release(struct inode *inode, struct file *file) | ||
110 | { | ||
111 | #ifdef ONLY_TESTING | ||
112 | free_irq(IRQ_TIMER4, NULL); | ||
113 | clear_bit(1, &timer_alive); | ||
114 | #endif | ||
115 | return 0; | ||
116 | } | ||
117 | |||
118 | static ssize_t | ||
119 | watchdog_write(struct file *file, const char *data, size_t len, loff_t *ppos) | ||
120 | { | ||
121 | /* | ||
122 | * Refresh the timer. | ||
123 | */ | ||
124 | if (len) | ||
125 | watchdog_ping(); | ||
126 | |||
127 | return len; | ||
128 | } | ||
129 | |||
130 | static struct watchdog_info ident = { | ||
131 | .options = WDIOF_SETTIMEOUT, | ||
132 | .identity = "Footbridge Watchdog", | ||
133 | }; | ||
134 | |||
135 | static int | ||
136 | watchdog_ioctl(struct inode *inode, struct file *file, unsigned int cmd, | ||
137 | unsigned long arg) | ||
138 | { | ||
139 | unsigned int new_margin; | ||
140 | int ret = -ENOIOCTLCMD; | ||
141 | |||
142 | switch(cmd) { | ||
143 | case WDIOC_GETSUPPORT: | ||
144 | ret = 0; | ||
145 | if (copy_to_user((void *)arg, &ident, sizeof(ident))) | ||
146 | ret = -EFAULT; | ||
147 | break; | ||
148 | |||
149 | case WDIOC_GETSTATUS: | ||
150 | case WDIOC_GETBOOTSTATUS: | ||
151 | ret = put_user(0,(int *)arg); | ||
152 | break; | ||
153 | |||
154 | case WDIOC_KEEPALIVE: | ||
155 | watchdog_ping(); | ||
156 | ret = 0; | ||
157 | break; | ||
158 | |||
159 | case WDIOC_SETTIMEOUT: | ||
160 | ret = get_user(new_margin, (int *)arg); | ||
161 | if (ret) | ||
162 | break; | ||
163 | |||
164 | /* Arbitrary, can't find the card's limits */ | ||
165 | if (new_margin < 0 || new_margin > 60) { | ||
166 | ret = -EINVAL; | ||
167 | break; | ||
168 | } | ||
169 | |||
170 | soft_margin = new_margin; | ||
171 | reload = soft_margin * (mem_fclk_21285 / 256); | ||
172 | watchdog_ping(); | ||
173 | /* Fall */ | ||
174 | case WDIOC_GETTIMEOUT: | ||
175 | ret = put_user(soft_margin, (int *)arg); | ||
176 | break; | ||
177 | } | ||
178 | return ret; | ||
179 | } | ||
180 | |||
181 | static struct file_operations watchdog_fops = { | ||
182 | .owner = THIS_MODULE, | ||
183 | .llseek = no_llseek, | ||
184 | .write = watchdog_write, | ||
185 | .ioctl = watchdog_ioctl, | ||
186 | .open = watchdog_open, | ||
187 | .release = watchdog_release, | ||
188 | }; | ||
189 | |||
190 | static struct miscdevice watchdog_miscdev = { | ||
191 | .minor = WATCHDOG_MINOR, | ||
192 | .name = "watchdog", | ||
193 | .fops = &watchdog_fops, | ||
194 | }; | ||
195 | |||
196 | static int __init footbridge_watchdog_init(void) | ||
197 | { | ||
198 | int retval; | ||
199 | |||
200 | if (machine_is_netwinder()) | ||
201 | return -ENODEV; | ||
202 | |||
203 | retval = misc_register(&watchdog_miscdev); | ||
204 | if (retval < 0) | ||
205 | return retval; | ||
206 | |||
207 | printk("Footbridge Watchdog Timer: 0.01, timer margin: %d sec\n", | ||
208 | soft_margin); | ||
209 | |||
210 | if (machine_is_cats()) | ||
211 | printk("Warning: Watchdog reset may not work on this machine.\n"); | ||
212 | return 0; | ||
213 | } | ||
214 | |||
215 | static void __exit footbridge_watchdog_exit(void) | ||
216 | { | ||
217 | misc_deregister(&watchdog_miscdev); | ||
218 | } | ||
219 | |||
220 | MODULE_AUTHOR("Phil Blundell <pb@nexus.co.uk>"); | ||
221 | MODULE_DESCRIPTION("Footbridge watchdog driver"); | ||
222 | MODULE_LICENSE("GPL"); | ||
223 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||
224 | |||
225 | module_param(soft_margin, int, 0); | ||
226 | MODULE_PARM_DESC(soft_margin,"Watchdog timeout in seconds"); | ||
227 | |||
228 | module_init(footbridge_watchdog_init); | ||
229 | module_exit(footbridge_watchdog_exit); | ||