Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
f30c2269 | 2 | * drivers/char/watchdog/ixp4xx_wdt.c |
1da177e4 LT |
3 | * |
4 | * Watchdog driver for Intel IXP4xx network processors | |
5 | * | |
6 | * Author: Deepak Saxena <dsaxena@plexity.net> | |
7 | * | |
8 | * Copyright 2004 (c) MontaVista, Software, Inc. | |
9 | * Based on sa1100 driver, Copyright (C) 2000 Oleg Drokin <green@crimea.edu> | |
10 | * | |
11 | * This file is licensed under the terms of the GNU General Public | |
12 | * License version 2. This program is licensed "as is" without any | |
13 | * warranty of any kind, whether express or implied. | |
14 | */ | |
15 | ||
1da177e4 LT |
16 | #include <linux/module.h> |
17 | #include <linux/moduleparam.h> | |
18 | #include <linux/types.h> | |
19 | #include <linux/kernel.h> | |
20 | #include <linux/fs.h> | |
21 | #include <linux/miscdevice.h> | |
22 | #include <linux/watchdog.h> | |
23 | #include <linux/init.h> | |
24 | #include <linux/bitops.h> | |
089ab079 | 25 | #include <linux/uaccess.h> |
a09e64fb | 26 | #include <mach/hardware.h> |
1da177e4 | 27 | |
4bfdf378 | 28 | static int nowayout = WATCHDOG_NOWAYOUT; |
1da177e4 LT |
29 | static int heartbeat = 60; /* (secs) Default is 1 minute */ |
30 | static unsigned long wdt_status; | |
31 | static unsigned long boot_status; | |
9229376e | 32 | static DEFINE_SPINLOCK(wdt_lock); |
1da177e4 LT |
33 | |
34 | #define WDT_TICK_RATE (IXP4XX_PERIPHERAL_BUS_CLOCK * 1000000UL) | |
35 | ||
36 | #define WDT_IN_USE 0 | |
37 | #define WDT_OK_TO_CLOSE 1 | |
38 | ||
20d35f3e | 39 | static void wdt_enable(void) |
1da177e4 | 40 | { |
20d35f3e | 41 | spin_lock(&wdt_lock); |
1da177e4 LT |
42 | *IXP4XX_OSWK = IXP4XX_WDT_KEY; |
43 | *IXP4XX_OSWE = 0; | |
44 | *IXP4XX_OSWT = WDT_TICK_RATE * heartbeat; | |
45 | *IXP4XX_OSWE = IXP4XX_WDT_COUNT_ENABLE | IXP4XX_WDT_RESET_ENABLE; | |
46 | *IXP4XX_OSWK = 0; | |
20d35f3e | 47 | spin_unlock(&wdt_lock); |
1da177e4 LT |
48 | } |
49 | ||
20d35f3e | 50 | static void wdt_disable(void) |
1da177e4 | 51 | { |
20d35f3e | 52 | spin_lock(&wdt_lock); |
1da177e4 LT |
53 | *IXP4XX_OSWK = IXP4XX_WDT_KEY; |
54 | *IXP4XX_OSWE = 0; | |
55 | *IXP4XX_OSWK = 0; | |
20d35f3e | 56 | spin_unlock(&wdt_lock); |
1da177e4 LT |
57 | } |
58 | ||
20d35f3e | 59 | static int ixp4xx_wdt_open(struct inode *inode, struct file *file) |
1da177e4 LT |
60 | { |
61 | if (test_and_set_bit(WDT_IN_USE, &wdt_status)) | |
62 | return -EBUSY; | |
63 | ||
64 | clear_bit(WDT_OK_TO_CLOSE, &wdt_status); | |
1da177e4 | 65 | wdt_enable(); |
1da177e4 LT |
66 | return nonseekable_open(inode, file); |
67 | } | |
68 | ||
69 | static ssize_t | |
70 | ixp4xx_wdt_write(struct file *file, const char *data, size_t len, loff_t *ppos) | |
71 | { | |
72 | if (len) { | |
73 | if (!nowayout) { | |
74 | size_t i; | |
75 | ||
76 | clear_bit(WDT_OK_TO_CLOSE, &wdt_status); | |
77 | ||
78 | for (i = 0; i != len; i++) { | |
79 | char c; | |
80 | ||
81 | if (get_user(c, data + i)) | |
82 | return -EFAULT; | |
83 | if (c == 'V') | |
84 | set_bit(WDT_OK_TO_CLOSE, &wdt_status); | |
85 | } | |
86 | } | |
87 | wdt_enable(); | |
88 | } | |
1da177e4 LT |
89 | return len; |
90 | } | |
91 | ||
92 | static struct watchdog_info ident = { | |
93 | .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE | | |
94 | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, | |
95 | .identity = "IXP4xx Watchdog", | |
96 | }; | |
97 | ||
98 | ||
20d35f3e AC |
99 | static long ixp4xx_wdt_ioctl(struct file *file, unsigned int cmd, |
100 | unsigned long arg) | |
1da177e4 | 101 | { |
795b89d2 | 102 | int ret = -ENOTTY; |
1da177e4 LT |
103 | int time; |
104 | ||
105 | switch (cmd) { | |
106 | case WDIOC_GETSUPPORT: | |
107 | ret = copy_to_user((struct watchdog_info *)arg, &ident, | |
108 | sizeof(ident)) ? -EFAULT : 0; | |
109 | break; | |
110 | ||
111 | case WDIOC_GETSTATUS: | |
112 | ret = put_user(0, (int *)arg); | |
113 | break; | |
114 | ||
115 | case WDIOC_GETBOOTSTATUS: | |
116 | ret = put_user(boot_status, (int *)arg); | |
117 | break; | |
118 | ||
0c06090c WVS |
119 | case WDIOC_KEEPALIVE: |
120 | wdt_enable(); | |
121 | ret = 0; | |
122 | break; | |
123 | ||
1da177e4 LT |
124 | case WDIOC_SETTIMEOUT: |
125 | ret = get_user(time, (int *)arg); | |
126 | if (ret) | |
127 | break; | |
128 | ||
129 | if (time <= 0 || time > 60) { | |
130 | ret = -EINVAL; | |
131 | break; | |
132 | } | |
133 | ||
134 | heartbeat = time; | |
135 | wdt_enable(); | |
136 | /* Fall through */ | |
137 | ||
138 | case WDIOC_GETTIMEOUT: | |
139 | ret = put_user(heartbeat, (int *)arg); | |
140 | break; | |
1da177e4 LT |
141 | } |
142 | return ret; | |
143 | } | |
144 | ||
20d35f3e | 145 | static int ixp4xx_wdt_release(struct inode *inode, struct file *file) |
1da177e4 | 146 | { |
20d35f3e | 147 | if (test_bit(WDT_OK_TO_CLOSE, &wdt_status)) |
1da177e4 | 148 | wdt_disable(); |
20d35f3e | 149 | else |
b36bbb6c | 150 | printk(KERN_CRIT "WATCHDOG: Device closed unexpectedly - " |
1da177e4 | 151 | "timer will not stop\n"); |
1da177e4 LT |
152 | clear_bit(WDT_IN_USE, &wdt_status); |
153 | clear_bit(WDT_OK_TO_CLOSE, &wdt_status); | |
154 | ||
155 | return 0; | |
156 | } | |
157 | ||
158 | ||
7944d3a5 | 159 | static const struct file_operations ixp4xx_wdt_fops = { |
1da177e4 LT |
160 | .owner = THIS_MODULE, |
161 | .llseek = no_llseek, | |
162 | .write = ixp4xx_wdt_write, | |
20d35f3e | 163 | .unlocked_ioctl = ixp4xx_wdt_ioctl, |
1da177e4 LT |
164 | .open = ixp4xx_wdt_open, |
165 | .release = ixp4xx_wdt_release, | |
166 | }; | |
167 | ||
7944d3a5 | 168 | static struct miscdevice ixp4xx_wdt_miscdev = { |
1da177e4 | 169 | .minor = WATCHDOG_MINOR, |
2dab3cab | 170 | .name = "watchdog", |
1da177e4 LT |
171 | .fops = &ixp4xx_wdt_fops, |
172 | }; | |
173 | ||
174 | static int __init ixp4xx_wdt_init(void) | |
175 | { | |
176 | int ret; | |
1da177e4 | 177 | |
0ba8b9b2 | 178 | if (!(read_cpuid_id() & 0xf) && !cpu_is_ixp46x()) { |
7944d3a5 WVS |
179 | printk(KERN_ERR "IXP4XXX Watchdog: Rev. A0 IXP42x CPU detected" |
180 | " - watchdog disabled\n"); | |
1da177e4 LT |
181 | |
182 | return -ENODEV; | |
183 | } | |
20d35f3e | 184 | spin_lock_init(&wdt_lock); |
1da177e4 LT |
185 | boot_status = (*IXP4XX_OSST & IXP4XX_OSST_TIMER_WARM_RESET) ? |
186 | WDIOF_CARDRESET : 0; | |
1da177e4 LT |
187 | ret = misc_register(&ixp4xx_wdt_miscdev); |
188 | if (ret == 0) | |
7944d3a5 WVS |
189 | printk(KERN_INFO "IXP4xx Watchdog Timer: heartbeat %d sec\n", |
190 | heartbeat); | |
1da177e4 LT |
191 | return ret; |
192 | } | |
193 | ||
194 | static void __exit ixp4xx_wdt_exit(void) | |
195 | { | |
196 | misc_deregister(&ixp4xx_wdt_miscdev); | |
197 | } | |
198 | ||
199 | ||
200 | module_init(ixp4xx_wdt_init); | |
201 | module_exit(ixp4xx_wdt_exit); | |
202 | ||
203 | MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>"); | |
204 | MODULE_DESCRIPTION("IXP4xx Network Processor Watchdog"); | |
205 | ||
206 | module_param(heartbeat, int, 0); | |
207 | MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds (default 60s)"); | |
208 | ||
209 | module_param(nowayout, int, 0); | |
210 | MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); | |
211 | ||
212 | MODULE_LICENSE("GPL"); | |
213 | MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); | |
214 |