2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
16 * Copyright (C) 2008 John Crispin <blogic@openwrt.org>
17 * Based on EP93xx wdt driver
20 #include <linux/module.h>
22 #include <linux/miscdevice.h>
23 #include <linux/miscdevice.h>
24 #include <linux/watchdog.h>
25 #include <linux/platform_device.h>
26 #include <linux/uaccess.h>
28 #include <asm/ifxmips/ifxmips_cgu.h>
29 #include <asm/ifxmips/ifxmips.h>
31 #define IFXMIPS_WDT_PW1 0x00BE0000
32 #define IFXMIPS_WDT_PW2 0x00DC0000
34 #ifndef CONFIG_WATCHDOG_NOWAYOUT
35 static int wdt_ok_to_close;
38 static int wdt_timeout = 30;
40 int ifxmips_wdt_enable(unsigned int timeout)
43 fpi = cgu_get_io_region_clock();
44 ifxmips_w32(IFXMIPS_WDT_PW1, IFXMIPS_BIU_WDT_CR);
45 ifxmips_w32(IFXMIPS_WDT_PW2 |
46 (0x3 << 26) | /* PWL */
47 (0x3 << 24) | /* CLKDIV */
48 (0x1 << 31) | /* enable */
49 ((timeout * (fpi / 0x40000)) + 0x1000), /* reload */
54 void ifxmips_wdt_disable(void)
56 #ifndef CONFIG_WATCHDOG_NOWAYOUT
59 ifxmips_w32(IFXMIPS_WDT_PW1, IFXMIPS_BIU_WDT_CR);
60 ifxmips_w32(IFXMIPS_WDT_PW2, IFXMIPS_BIU_WDT_CR);
63 static ssize_t ifxmips_wdt_write(struct file *file, const char __user *data,
64 size_t len, loff_t *ppos)
71 #ifndef CONFIG_WATCHDOG_NOWAYOUT
72 for (i = 0; i != len; i++) {
74 if (get_user(c, data + i))
80 ifxmips_wdt_enable(wdt_timeout);
84 static struct watchdog_info ident = {
85 .options = WDIOF_MAGICCLOSE,
86 .identity = "ifxmips Watchdog",
89 static int ifxmips_wdt_ioctl(struct inode *inode, struct file *file,
90 unsigned int cmd, unsigned long arg)
95 case WDIOC_GETSUPPORT:
96 ret = copy_to_user((struct watchdog_info __user *)arg, &ident,
97 sizeof(ident)) ? -EFAULT : 0;
100 case WDIOC_GETTIMEOUT:
101 ret = put_user(wdt_timeout, (int __user *)arg);
104 case WDIOC_SETTIMEOUT:
105 ret = get_user(wdt_timeout, (int __user *)arg);
108 case WDIOC_KEEPALIVE:
109 ifxmips_wdt_enable(wdt_timeout);
116 static int ifxmips_wdt_open(struct inode *inode, struct file *file)
118 ifxmips_wdt_enable(wdt_timeout);
119 return nonseekable_open(inode, file);
122 static int ifxmips_wdt_release(struct inode *inode, struct file *file)
124 #ifndef CONFIG_WATCHDOG_NOWAYOUT
126 ifxmips_wdt_disable();
129 printk(KERN_ERR "ifxmips_wdt: watchdog closed without warning,"
130 " rebooting system\n");
134 static const struct file_operations ifxmips_wdt_fops = {
135 .owner = THIS_MODULE,
136 .write = ifxmips_wdt_write,
137 .ioctl = ifxmips_wdt_ioctl,
138 .open = ifxmips_wdt_open,
139 .release = ifxmips_wdt_release,
142 static struct miscdevice ifxmips_wdt_miscdev = {
143 .minor = WATCHDOG_MINOR,
145 .fops = &ifxmips_wdt_fops,
148 static int ifxmips_wdt_probe(struct platform_device *dev)
151 err = misc_register(&ifxmips_wdt_miscdev);
153 printk(KERN_INFO "ifxmips_wdt: error creating device\n");
155 printk(KERN_INFO "ifxmips_wdt: loaded\n");
159 static int ifxmips_wdt_remove(struct platform_device *dev)
161 ifxmips_wdt_disable();
162 misc_deregister(&ifxmips_wdt_miscdev);
167 static struct platform_driver ifxmips_wdt_driver = {
168 .probe = ifxmips_wdt_probe,
169 .remove = ifxmips_wdt_remove,
171 .name = "ifxmips_wdt",
172 .owner = THIS_MODULE,
176 static int __init init_ifxmips_wdt(void)
178 int ret = platform_driver_register(&ifxmips_wdt_driver);
180 printk(KERN_INFO "ifxmips_wdt: error registering platfom driver!");
184 static void __exit exit_ifxmips_wdt(void)
186 platform_driver_unregister(&ifxmips_wdt_driver);
189 module_init(init_ifxmips_wdt);
190 module_exit(exit_ifxmips_wdt);
192 MODULE_AUTHOR("John Crispin <blogic@openwrt.org>");
193 MODULE_DESCRIPTION("ifxmips Watchdog");
194 MODULE_LICENSE("GPL");
195 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);