Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Watchdog driver for the SA11x0/PXA2xx | |
3 | * | |
4 | * (c) Copyright 2000 Oleg Drokin <green@crimea.edu> | |
29fa0586 | 5 | * Based on SoftDog driver by Alan Cox <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
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 | */ | |
1da177e4 LT |
20 | #include <linux/module.h> |
21 | #include <linux/moduleparam.h> | |
22 | #include <linux/types.h> | |
23 | #include <linux/kernel.h> | |
24 | #include <linux/fs.h> | |
25 | #include <linux/miscdevice.h> | |
26 | #include <linux/watchdog.h> | |
27 | #include <linux/init.h> | |
1977f032 | 28 | #include <linux/bitops.h> |
f19e0312 | 29 | #include <linux/uaccess.h> |
87c52578 | 30 | #include <linux/timex.h> |
1da177e4 LT |
31 | |
32 | #ifdef CONFIG_ARCH_PXA | |
a09e64fb | 33 | #include <mach/pxa-regs.h> |
1da177e4 LT |
34 | #endif |
35 | ||
afd2fc02 | 36 | #include <mach/reset.h> |
a09e64fb | 37 | #include <mach/hardware.h> |
1da177e4 | 38 | |
28a62385 | 39 | static unsigned long oscr_freq; |
1da177e4 | 40 | static unsigned long sa1100wdt_users; |
1da177e4 LT |
41 | static int pre_margin; |
42 | static int boot_status; | |
1da177e4 LT |
43 | |
44 | /* | |
45 | * Allow only one person to hold it open | |
46 | */ | |
47 | static int sa1100dog_open(struct inode *inode, struct file *file) | |
48 | { | |
f19e0312 | 49 | if (test_and_set_bit(1, &sa1100wdt_users)) |
1da177e4 LT |
50 | return -EBUSY; |
51 | ||
52 | /* Activate SA1100 Watchdog timer */ | |
53 | OSMR3 = OSCR + pre_margin; | |
54 | OSSR = OSSR_M3; | |
55 | OWER = OWER_WME; | |
56 | OIER |= OIER_E3; | |
6abe78bf | 57 | return nonseekable_open(inode, file); |
1da177e4 LT |
58 | } |
59 | ||
60 | /* | |
9bbd0375 IC |
61 | * The watchdog cannot be disabled. |
62 | * | |
63 | * Previous comments suggested that turning off the interrupt by | |
64 | * clearing OIER[E3] would prevent the watchdog timing out but this | |
65 | * does not appear to be true (at least on the PXA255). | |
1da177e4 LT |
66 | */ |
67 | static int sa1100dog_release(struct inode *inode, struct file *file) | |
68 | { | |
9bbd0375 | 69 | printk(KERN_CRIT "WATCHDOG: Device closed - timer will not stop\n"); |
1da177e4 | 70 | clear_bit(1, &sa1100wdt_users); |
1da177e4 LT |
71 | return 0; |
72 | } | |
73 | ||
f19e0312 AC |
74 | static ssize_t sa1100dog_write(struct file *file, const char __user *data, |
75 | size_t len, loff_t *ppos) | |
1da177e4 | 76 | { |
9bbd0375 | 77 | if (len) |
1da177e4 LT |
78 | /* Refresh OSMR3 timer. */ |
79 | OSMR3 = OSCR + pre_margin; | |
1da177e4 LT |
80 | return len; |
81 | } | |
82 | ||
f19e0312 AC |
83 | static const struct watchdog_info ident = { |
84 | .options = WDIOF_CARDRESET | WDIOF_SETTIMEOUT | |
85 | | WDIOF_KEEPALIVEPING, | |
9bbd0375 | 86 | .identity = "SA1100/PXA255 Watchdog", |
1da177e4 LT |
87 | }; |
88 | ||
f19e0312 AC |
89 | static long sa1100dog_ioctl(struct file *file, unsigned int cmd, |
90 | unsigned long arg) | |
1da177e4 | 91 | { |
795b89d2 | 92 | int ret = -ENOTTY; |
1da177e4 | 93 | int time; |
3a69e579 IC |
94 | void __user *argp = (void __user *)arg; |
95 | int __user *p = argp; | |
1da177e4 LT |
96 | |
97 | switch (cmd) { | |
98 | case WDIOC_GETSUPPORT: | |
3a69e579 | 99 | ret = copy_to_user(argp, &ident, |
1da177e4 LT |
100 | sizeof(ident)) ? -EFAULT : 0; |
101 | break; | |
102 | ||
103 | case WDIOC_GETSTATUS: | |
3a69e579 | 104 | ret = put_user(0, p); |
1da177e4 LT |
105 | break; |
106 | ||
107 | case WDIOC_GETBOOTSTATUS: | |
3a69e579 | 108 | ret = put_user(boot_status, p); |
1da177e4 LT |
109 | break; |
110 | ||
0c06090c WVS |
111 | case WDIOC_KEEPALIVE: |
112 | OSMR3 = OSCR + pre_margin; | |
113 | ret = 0; | |
114 | break; | |
115 | ||
1da177e4 | 116 | case WDIOC_SETTIMEOUT: |
3a69e579 | 117 | ret = get_user(time, p); |
1da177e4 LT |
118 | if (ret) |
119 | break; | |
120 | ||
121 | if (time <= 0 || time > 255) { | |
122 | ret = -EINVAL; | |
123 | break; | |
124 | } | |
125 | ||
28a62385 | 126 | pre_margin = oscr_freq * time; |
1da177e4 LT |
127 | OSMR3 = OSCR + pre_margin; |
128 | /*fall through*/ | |
129 | ||
130 | case WDIOC_GETTIMEOUT: | |
28a62385 | 131 | ret = put_user(pre_margin / oscr_freq, p); |
1da177e4 | 132 | break; |
1da177e4 LT |
133 | } |
134 | return ret; | |
135 | } | |
136 | ||
f19e0312 | 137 | static const struct file_operations sa1100dog_fops = { |
1da177e4 LT |
138 | .owner = THIS_MODULE, |
139 | .llseek = no_llseek, | |
140 | .write = sa1100dog_write, | |
f19e0312 | 141 | .unlocked_ioctl = sa1100dog_ioctl, |
1da177e4 LT |
142 | .open = sa1100dog_open, |
143 | .release = sa1100dog_release, | |
144 | }; | |
145 | ||
f19e0312 | 146 | static struct miscdevice sa1100dog_miscdev = { |
1da177e4 | 147 | .minor = WATCHDOG_MINOR, |
9bbd0375 | 148 | .name = "watchdog", |
1da177e4 LT |
149 | .fops = &sa1100dog_fops, |
150 | }; | |
151 | ||
152 | static int margin __initdata = 60; /* (secs) Default is 1 minute */ | |
153 | ||
154 | static int __init sa1100dog_init(void) | |
155 | { | |
156 | int ret; | |
157 | ||
28a62385 EM |
158 | oscr_freq = get_clock_tick_rate(); |
159 | ||
1da177e4 LT |
160 | /* |
161 | * Read the reset status, and save it for later. If | |
162 | * we suspend, RCSR will be cleared, and the watchdog | |
163 | * reset reason will be lost. | |
164 | */ | |
214c6a7e EM |
165 | boot_status = (reset_status & RESET_STATUS_WATCHDOG) ? |
166 | WDIOF_CARDRESET : 0; | |
28a62385 | 167 | pre_margin = oscr_freq * margin; |
1da177e4 LT |
168 | |
169 | ret = misc_register(&sa1100dog_miscdev); | |
170 | if (ret == 0) | |
f19e0312 AC |
171 | printk(KERN_INFO |
172 | "SA1100/PXA2xx Watchdog Timer: timer margin %d sec\n", | |
173 | margin); | |
1da177e4 LT |
174 | return ret; |
175 | } | |
176 | ||
177 | static void __exit sa1100dog_exit(void) | |
178 | { | |
179 | misc_deregister(&sa1100dog_miscdev); | |
180 | } | |
181 | ||
182 | module_init(sa1100dog_init); | |
183 | module_exit(sa1100dog_exit); | |
184 | ||
185 | MODULE_AUTHOR("Oleg Drokin <green@crimea.edu>"); | |
186 | MODULE_DESCRIPTION("SA1100/PXA2xx Watchdog"); | |
187 | ||
188 | module_param(margin, int, 0); | |
189 | MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)"); | |
190 | ||
1da177e4 LT |
191 | MODULE_LICENSE("GPL"); |
192 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |