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Diffstat (limited to 'drivers/watchdog/mtx-1_wdt.c')
-rw-r--r--drivers/watchdog/mtx-1_wdt.c239
1 files changed, 239 insertions, 0 deletions
diff --git a/drivers/watchdog/mtx-1_wdt.c b/drivers/watchdog/mtx-1_wdt.c
new file mode 100644
index 000000000000..dcfd401a7ad7
--- /dev/null
+++ b/drivers/watchdog/mtx-1_wdt.c
@@ -0,0 +1,239 @@
1/*
2 * Driver for the MTX-1 Watchdog.
3 *
4 * (C) Copyright 2005 4G Systems <info@4g-systems.biz>, All Rights Reserved.
5 * http://www.4g-systems.biz
6 *
7 * (C) Copyright 2007 OpenWrt.org, Florian Fainelli <florian@openwrt.org>
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License
11 * as published by the Free Software Foundation; either version
12 * 2 of the License, or (at your option) any later version.
13 *
14 * Neither Michael Stickel nor 4G Systems admit liability nor provide
15 * warranty for any of this software. This material is provided
16 * "AS-IS" and at no charge.
17 *
18 * (c) Copyright 2005 4G Systems <info@4g-systems.biz>
19 *
20 * Release 0.01.
21 * Author: Michael Stickel michael.stickel@4g-systems.biz
22 *
23 * Release 0.02.
24 * Author: Florian Fainelli florian@openwrt.org
25 * use the Linux watchdog/timer APIs
26 *
27 * The Watchdog is configured to reset the MTX-1
28 * if it is not triggered for 100 seconds.
29 * It should not be triggered more often than 1.6 seconds.
30 *
31 * A timer triggers the watchdog every 5 seconds, until
32 * it is opened for the first time. After the first open
33 * it MUST be triggered every 2..95 seconds.
34 */
35
36#include <linux/module.h>
37#include <linux/moduleparam.h>
38#include <linux/types.h>
39#include <linux/errno.h>
40#include <linux/miscdevice.h>
41#include <linux/fs.h>
42#include <linux/init.h>
43#include <linux/ioport.h>
44#include <linux/timer.h>
45#include <linux/completion.h>
46#include <linux/jiffies.h>
47#include <linux/watchdog.h>
48#include <asm/io.h>
49#include <asm/uaccess.h>
50
51#include <asm/mach-au1x00/au1000.h>
52
53#define MTX1_WDT_INTERVAL (5 * HZ)
54
55static int ticks = 100 * HZ;
56
57static struct {
58 struct completion stop;
59 volatile int running;
60 struct timer_list timer;
61 volatile int queue;
62 int default_ticks;
63 unsigned long inuse;
64} mtx1_wdt_device;
65
66static void mtx1_wdt_trigger(unsigned long unused)
67{
68 u32 tmp;
69
70 if (mtx1_wdt_device.running)
71 ticks--;
72 /*
73 * toggle GPIO2_15
74 */
75 tmp = au_readl(GPIO2_DIR);
76 tmp = (tmp & ~(1<<15)) | ((~tmp) & (1<<15));
77 au_writel (tmp, GPIO2_DIR);
78
79 if (mtx1_wdt_device.queue && ticks)
80 mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
81 else {
82 complete(&mtx1_wdt_device.stop);
83 }
84}
85
86static void mtx1_wdt_reset(void)
87{
88 ticks = mtx1_wdt_device.default_ticks;
89}
90
91
92static void mtx1_wdt_start(void)
93{
94 if (!mtx1_wdt_device.queue) {
95 mtx1_wdt_device.queue = 1;
96 au_writel (au_readl(GPIO2_DIR) | (u32)(1<<15), GPIO2_DIR);
97 mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
98 }
99 mtx1_wdt_device.running++;
100}
101
102static int mtx1_wdt_stop(void)
103{
104 if (mtx1_wdt_device.queue) {
105 mtx1_wdt_device.queue = 0;
106 au_writel (au_readl(GPIO2_DIR) & ~((u32)(1<<15)), GPIO2_DIR);
107 }
108
109 ticks = mtx1_wdt_device.default_ticks;
110
111 return 0;
112}
113
114/* Filesystem functions */
115
116static int mtx1_wdt_open(struct inode *inode, struct file *file)
117{
118 if (test_and_set_bit(0, &mtx1_wdt_device.inuse))
119 return -EBUSY;
120
121 return nonseekable_open(inode, file);
122}
123
124
125static int mtx1_wdt_release(struct inode *inode, struct file *file)
126{
127 clear_bit(0, &mtx1_wdt_device.inuse);
128 return 0;
129}
130
131static int mtx1_wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
132{
133 void __user *argp = (void __user *)arg;
134 unsigned int value;
135 static struct watchdog_info ident =
136 {
137 .options = WDIOF_CARDRESET,
138 .identity = "MTX-1 WDT",
139 };
140
141 switch(cmd) {
142 case WDIOC_KEEPALIVE:
143 mtx1_wdt_reset();
144 break;
145 case WDIOC_GETSTATUS:
146 case WDIOC_GETBOOTSTATUS:
147 if ( copy_to_user(argp, &value, sizeof(int)) )
148 return -EFAULT;
149 break;
150 case WDIOC_GETSUPPORT:
151 if ( copy_to_user(argp, &ident, sizeof(ident)) )
152 return -EFAULT;
153 break;
154 case WDIOC_SETOPTIONS:
155 if ( copy_from_user(&value, argp, sizeof(int)) )
156 return -EFAULT;
157 switch(value) {
158 case WDIOS_ENABLECARD:
159 mtx1_wdt_start();
160 break;
161 case WDIOS_DISABLECARD:
162 return mtx1_wdt_stop();
163 default:
164 return -EINVAL;
165 }
166 break;
167 default:
168 return -ENOTTY;
169 }
170 return 0;
171}
172
173
174static ssize_t mtx1_wdt_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
175{
176 if (!count)
177 return -EIO;
178
179 mtx1_wdt_reset();
180 return count;
181}
182
183static struct file_operations mtx1_wdt_fops = {
184 .owner = THIS_MODULE,
185 .llseek = no_llseek,
186 .ioctl = mtx1_wdt_ioctl,
187 .open = mtx1_wdt_open,
188 .write = mtx1_wdt_write,
189 .release = mtx1_wdt_release
190};
191
192
193static struct miscdevice mtx1_wdt_misc = {
194 .minor = WATCHDOG_MINOR,
195 .name = "watchdog",
196 .fops = &mtx1_wdt_fops
197};
198
199
200static int __init mtx1_wdt_init(void)
201{
202 int ret;
203
204 if ((ret = misc_register(&mtx1_wdt_misc)) < 0) {
205 printk(KERN_ERR " mtx-1_wdt : failed to register\n");
206 return ret;
207 }
208
209 init_completion(&mtx1_wdt_device.stop);
210 mtx1_wdt_device.queue = 0;
211
212 clear_bit(0, &mtx1_wdt_device.inuse);
213
214 setup_timer(&mtx1_wdt_device.timer, mtx1_wdt_trigger, 0L);
215
216 mtx1_wdt_device.default_ticks = ticks;
217
218 mtx1_wdt_start();
219
220 printk(KERN_INFO "MTX-1 Watchdog driver\n");
221
222 return 0;
223}
224
225static void __exit mtx1_wdt_exit(void)
226{
227 if (mtx1_wdt_device.queue) {
228 mtx1_wdt_device.queue = 0;
229 wait_for_completion(&mtx1_wdt_device.stop);
230 }
231 misc_deregister(&mtx1_wdt_misc);
232}
233
234module_init(mtx1_wdt_init);
235module_exit(mtx1_wdt_exit);
236
237MODULE_AUTHOR("Michael Stickel, Florian Fainelli");
238MODULE_DESCRIPTION("Driver for the MTX-1 watchdog");
239MODULE_LICENSE("GPL");