1 /*
2 * mpc8xx_wdt.c - MPC8xx watchdog userspace interface
3 *
4 * Author: Florian Schirmer <jolt@tuxbox.org>
5 *
6 * 2002 (c) Florian Schirmer <jolt@tuxbox.org> This file is licensed under
7 * the terms of the GNU General Public License version 2. This program
8 * is licensed "as is" without any warranty of any kind, whether express
9 * or implied.
10 */
11
12 #include <linux/config.h>
13 #include <linux/fs.h>
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/miscdevice.h>
17 #include <linux/module.h>
18 #include <linux/watchdog.h>
19 #include <asm/8xx_immap.h>
20 #include <asm/uaccess.h>
21 #include <syslib/m8xx_wdt.h>
22
23 static unsigned long wdt_opened;
24 static int wdt_status;
25
26 static void mpc8xx_wdt_handler_disable(void)
27 {
28 volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR;
29
30 imap->im_sit.sit_piscr &= ~(PISCR_PIE | PISCR_PTE);
31
32 printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler deactivated\n");
33 }
34
35 static void mpc8xx_wdt_handler_enable(void)
36 {
37 volatile immap_t *imap = (volatile immap_t *)IMAP_ADDR;
38
39 imap->im_sit.sit_piscr |= PISCR_PIE | PISCR_PTE;
40
41 printk(KERN_NOTICE "mpc8xx_wdt: keep-alive handler activated\n");
42 }
43
44 static int mpc8xx_wdt_open(struct inode *inode, struct file *file)
45 {
46 if (test_and_set_bit(0, &wdt_opened))
47 return -EBUSY;
48
49 m8xx_wdt_reset();
50 mpc8xx_wdt_handler_disable();
51
52 return 0;
53 }
54
55 static int mpc8xx_wdt_release(struct inode *inode, struct file *file)
56 {
57 m8xx_wdt_reset();
58
59 #if !defined(CONFIG_WATCHDOG_NOWAYOUT)
60 mpc8xx_wdt_handler_enable();
61 #endif
62
63 clear_bit(0, &wdt_opened);
64
65 return 0;
66 }
67
68 static ssize_t mpc8xx_wdt_write(struct file *file, const char *data, size_t len,
69 loff_t * ppos)
70 {
71 if (ppos != &file->f_pos)
72 return -ESPIPE;
73
74 if (len)
75 m8xx_wdt_reset();
76
77 return len;
78 }
79
80 static int mpc8xx_wdt_ioctl(struct inode *inode, struct file *file,
81 unsigned int cmd, unsigned long arg)
82 {
83 int timeout;
84 static struct watchdog_info info = {
85 .options = WDIOF_KEEPALIVEPING,
86 .firmware_version = 0,
87 .identity = "MPC8xx watchdog",
88 };
89
90 switch (cmd) {
91 case WDIOC_GETSUPPORT:
92 if (copy_to_user((void *)arg, &info, sizeof(info)))
93 return -EFAULT;
94 break;
95
96 case WDIOC_GETSTATUS:
97 case WDIOC_GETBOOTSTATUS:
98 if (put_user(wdt_status, (int *)arg))
99 return -EFAULT;
100 wdt_status &= ~WDIOF_KEEPALIVEPING;
101 break;
102
103 case WDIOC_GETTEMP:
104 return -EOPNOTSUPP;
105
106 case WDIOC_SETOPTIONS:
107 return -EOPNOTSUPP;
108
109 case WDIOC_KEEPALIVE:
110 m8xx_wdt_reset();
111 wdt_status |= WDIOF_KEEPALIVEPING;
112 break;
113
114 case WDIOC_SETTIMEOUT:
115 return -EOPNOTSUPP;
116
117 case WDIOC_GETTIMEOUT:
118 timeout = m8xx_wdt_get_timeout();
119 if (put_user(timeout, (int *)arg))
120 return -EFAULT;
121 break;
122
123 default:
124 return -ENOIOCTLCMD;
125 }
126
127 return 0;
128 }
129
130 static struct file_operations mpc8xx_wdt_fops = {
131 .owner = THIS_MODULE,
132 .llseek = no_llseek,
133 .write = mpc8xx_wdt_write,
134 .ioctl = mpc8xx_wdt_ioctl,
135 .open = mpc8xx_wdt_open,
136 .release = mpc8xx_wdt_release,
137 };
138
139 static struct miscdevice mpc8xx_wdt_miscdev = {
140 .minor = WATCHDOG_MINOR,
141 .name = "watchdog",
142 .fops = &mpc8xx_wdt_fops,
143 };
144
145 static int __init mpc8xx_wdt_init(void)
146 {
147 return misc_register(&mpc8xx_wdt_miscdev);
148 }
149
150 static void __exit mpc8xx_wdt_exit(void)
151 {
152 misc_deregister(&mpc8xx_wdt_miscdev);
153
154 m8xx_wdt_reset();
155 mpc8xx_wdt_handler_enable();
156 }
157
158 module_init(mpc8xx_wdt_init);
159 module_exit(mpc8xx_wdt_exit);
160
161 MODULE_AUTHOR("Florian Schirmer <jolt@tuxbox.org>");
162 MODULE_DESCRIPTION("MPC8xx watchdog driver");
163 MODULE_LICENSE("GPL");
164 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
165
|
This page was automatically generated by the
LXR engine.
|