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/sa1100_wdt.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/sa1100_wdt.c')
-rw-r--r-- | drivers/char/watchdog/sa1100_wdt.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/char/watchdog/sa1100_wdt.c b/drivers/char/watchdog/sa1100_wdt.c new file mode 100644 index 000000000000..34e8f7b15e30 --- /dev/null +++ b/drivers/char/watchdog/sa1100_wdt.c | |||
@@ -0,0 +1,223 @@ | |||
1 | /* | ||
2 | * Watchdog driver for the SA11x0/PXA2xx | ||
3 | * | ||
4 | * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> | ||
5 | * Based on SoftDog driver by Alan Cox <alan@redhat.com> | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or | ||
8 | * modify it under the terms of the GNU General Public License | ||
9 | * as published by the Free Software Foundation; either version | ||
10 | * 2 of the License, or (at your option) any later version. | ||
11 | * | ||
12 | * Neither Oleg Drokin nor iXcelerator.com admit liability nor provide | ||
13 | * warranty for any of this software. This material is provided | ||
14 | * "AS-IS" and at no charge. | ||
15 | * | ||
16 | * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> | ||
17 | * | ||
18 | * 27/11/2000 Initial release | ||
19 | */ | ||
20 | #include <linux/config.h> | ||
21 | #include <linux/module.h> | ||
22 | #include <linux/moduleparam.h> | ||
23 | #include <linux/types.h> | ||
24 | #include <linux/kernel.h> | ||
25 | #include <linux/fs.h> | ||
26 | #include <linux/miscdevice.h> | ||
27 | #include <linux/watchdog.h> | ||
28 | #include <linux/init.h> | ||
29 | |||
30 | #ifdef CONFIG_ARCH_PXA | ||
31 | #include <asm/arch/pxa-regs.h> | ||
32 | #endif | ||
33 | |||
34 | #include <asm/hardware.h> | ||
35 | #include <asm/bitops.h> | ||
36 | #include <asm/uaccess.h> | ||
37 | |||
38 | #define OSCR_FREQ CLOCK_TICK_RATE | ||
39 | #define SA1100_CLOSE_MAGIC (0x5afc4453) | ||
40 | |||
41 | static unsigned long sa1100wdt_users; | ||
42 | static int expect_close; | ||
43 | static int pre_margin; | ||
44 | static int boot_status; | ||
45 | #ifdef CONFIG_WATCHDOG_NOWAYOUT | ||
46 | static int nowayout = 1; | ||
47 | #else | ||
48 | static int nowayout = 0; | ||
49 | #endif | ||
50 | |||
51 | /* | ||
52 | * Allow only one person to hold it open | ||
53 | */ | ||
54 | static int sa1100dog_open(struct inode *inode, struct file *file) | ||
55 | { | ||
56 | nonseekable_open(inode, file); | ||
57 | if (test_and_set_bit(1,&sa1100wdt_users)) | ||
58 | return -EBUSY; | ||
59 | |||
60 | /* Activate SA1100 Watchdog timer */ | ||
61 | OSMR3 = OSCR + pre_margin; | ||
62 | OSSR = OSSR_M3; | ||
63 | OWER = OWER_WME; | ||
64 | OIER |= OIER_E3; | ||
65 | return 0; | ||
66 | } | ||
67 | |||
68 | /* | ||
69 | * Shut off the timer. | ||
70 | * Lock it in if it's a module and we defined ...NOWAYOUT | ||
71 | * Oddly, the watchdog can only be enabled, but we can turn off | ||
72 | * the interrupt, which appears to prevent the watchdog timing out. | ||
73 | */ | ||
74 | static int sa1100dog_release(struct inode *inode, struct file *file) | ||
75 | { | ||
76 | OSMR3 = OSCR + pre_margin; | ||
77 | |||
78 | if (expect_close == SA1100_CLOSE_MAGIC) { | ||
79 | OIER &= ~OIER_E3; | ||
80 | } else { | ||
81 | printk(KERN_CRIT "WATCHDOG: WDT device closed unexpectedly. WDT will not stop!\n"); | ||
82 | } | ||
83 | |||
84 | clear_bit(1, &sa1100wdt_users); | ||
85 | expect_close = 0; | ||
86 | |||
87 | return 0; | ||
88 | } | ||
89 | |||
90 | static ssize_t sa1100dog_write(struct file *file, const char *data, size_t len, loff_t *ppos) | ||
91 | { | ||
92 | if (len) { | ||
93 | if (!nowayout) { | ||
94 | size_t i; | ||
95 | |||
96 | expect_close = 0; | ||
97 | |||
98 | for (i = 0; i != len; i++) { | ||
99 | char c; | ||
100 | |||
101 | if (get_user(c, data + i)) | ||
102 | return -EFAULT; | ||
103 | if (c == 'V') | ||
104 | expect_close = SA1100_CLOSE_MAGIC; | ||
105 | } | ||
106 | } | ||
107 | /* Refresh OSMR3 timer. */ | ||
108 | OSMR3 = OSCR + pre_margin; | ||
109 | } | ||
110 | |||
111 | return len; | ||
112 | } | ||
113 | |||
114 | static struct watchdog_info ident = { | ||
115 | .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | | ||
116 | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, | ||
117 | .identity = "SA1100 Watchdog", | ||
118 | }; | ||
119 | |||
120 | static int sa1100dog_ioctl(struct inode *inode, struct file *file, | ||
121 | unsigned int cmd, unsigned long arg) | ||
122 | { | ||
123 | int ret = -ENOIOCTLCMD; | ||
124 | int time; | ||
125 | |||
126 | switch (cmd) { | ||
127 | case WDIOC_GETSUPPORT: | ||
128 | ret = copy_to_user((struct watchdog_info *)arg, &ident, | ||
129 | sizeof(ident)) ? -EFAULT : 0; | ||
130 | break; | ||
131 | |||
132 | case WDIOC_GETSTATUS: | ||
133 | ret = put_user(0, (int *)arg); | ||
134 | break; | ||
135 | |||
136 | case WDIOC_GETBOOTSTATUS: | ||
137 | ret = put_user(boot_status, (int *)arg); | ||
138 | break; | ||
139 | |||
140 | case WDIOC_SETTIMEOUT: | ||
141 | ret = get_user(time, (int *)arg); | ||
142 | if (ret) | ||
143 | break; | ||
144 | |||
145 | if (time <= 0 || time > 255) { | ||
146 | ret = -EINVAL; | ||
147 | break; | ||
148 | } | ||
149 | |||
150 | pre_margin = OSCR_FREQ * time; | ||
151 | OSMR3 = OSCR + pre_margin; | ||
152 | /*fall through*/ | ||
153 | |||
154 | case WDIOC_GETTIMEOUT: | ||
155 | ret = put_user(pre_margin / OSCR_FREQ, (int *)arg); | ||
156 | break; | ||
157 | |||
158 | case WDIOC_KEEPALIVE: | ||
159 | OSMR3 = OSCR + pre_margin; | ||
160 | ret = 0; | ||
161 | break; | ||
162 | } | ||
163 | return ret; | ||
164 | } | ||
165 | |||
166 | static struct file_operations sa1100dog_fops = | ||
167 | { | ||
168 | .owner = THIS_MODULE, | ||
169 | .llseek = no_llseek, | ||
170 | .write = sa1100dog_write, | ||
171 | .ioctl = sa1100dog_ioctl, | ||
172 | .open = sa1100dog_open, | ||
173 | .release = sa1100dog_release, | ||
174 | }; | ||
175 | |||
176 | static struct miscdevice sa1100dog_miscdev = | ||
177 | { | ||
178 | .minor = WATCHDOG_MINOR, | ||
179 | .name = "SA1100/PXA2xx watchdog", | ||
180 | .fops = &sa1100dog_fops, | ||
181 | }; | ||
182 | |||
183 | static int margin __initdata = 60; /* (secs) Default is 1 minute */ | ||
184 | |||
185 | static int __init sa1100dog_init(void) | ||
186 | { | ||
187 | int ret; | ||
188 | |||
189 | /* | ||
190 | * Read the reset status, and save it for later. If | ||
191 | * we suspend, RCSR will be cleared, and the watchdog | ||
192 | * reset reason will be lost. | ||
193 | */ | ||
194 | boot_status = (RCSR & RCSR_WDR) ? WDIOF_CARDRESET : 0; | ||
195 | pre_margin = OSCR_FREQ * margin; | ||
196 | |||
197 | ret = misc_register(&sa1100dog_miscdev); | ||
198 | if (ret == 0) | ||
199 | printk("SA1100/PXA2xx Watchdog Timer: timer margin %d sec\n", | ||
200 | margin); | ||
201 | |||
202 | return ret; | ||
203 | } | ||
204 | |||
205 | static void __exit sa1100dog_exit(void) | ||
206 | { | ||
207 | misc_deregister(&sa1100dog_miscdev); | ||
208 | } | ||
209 | |||
210 | module_init(sa1100dog_init); | ||
211 | module_exit(sa1100dog_exit); | ||
212 | |||
213 | MODULE_AUTHOR("Oleg Drokin <green@crimea.edu>"); | ||
214 | MODULE_DESCRIPTION("SA1100/PXA2xx Watchdog"); | ||
215 | |||
216 | module_param(margin, int, 0); | ||
217 | MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)"); | ||
218 | |||
219 | module_param(nowayout, int, 0); | ||
220 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); | ||
221 | |||
222 | MODULE_LICENSE("GPL"); | ||
223 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | ||