1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
|
/*
* Driver for the MTX-1 Watchdog.
*
* (C) Copyright 2005 4G Systems <info@4g-systems.biz>,
* All Rights Reserved.
* http://www.4g-systems.biz
*
* (C) Copyright 2007 OpenWrt.org, Florian Fainelli <florian@openwrt.org>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*
* Neither Michael Stickel nor 4G Systems admit liability nor provide
* warranty for any of this software. This material is provided
* "AS-IS" and at no charge.
*
* (c) Copyright 2005 4G Systems <info@4g-systems.biz>
*
* Release 0.01.
* Author: Michael Stickel michael.stickel@4g-systems.biz
*
* Release 0.02.
* Author: Florian Fainelli florian@openwrt.org
* use the Linux watchdog/timer APIs
*
* The Watchdog is configured to reset the MTX-1
* if it is not triggered for 100 seconds.
* It should not be triggered more often than 1.6 seconds.
*
* A timer triggers the watchdog every 5 seconds, until
* it is opened for the first time. After the first open
* it MUST be triggered every 2..95 seconds.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/timer.h>
#include <linux/completion.h>
#include <linux/jiffies.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/uaccess.h>
#include <linux/gpio.h>
#include <asm/mach-au1x00/au1000.h>
#define MTX1_WDT_INTERVAL (5 * HZ)
static int ticks = 100 * HZ;
static struct {
struct completion stop;
spinlock_t lock;
int running;
struct timer_list timer;
int queue;
int default_ticks;
unsigned long inuse;
unsigned gpio;
} mtx1_wdt_device;
static void mtx1_wdt_trigger(unsigned long unused)
{
u32 tmp;
spin_lock(&mtx1_wdt_device.lock);
if (mtx1_wdt_device.running)
ticks--;
/*
* toggle GPIO2_15
*/
tmp = au_readl(GPIO2_DIR);
tmp = (tmp & ~(1 << mtx1_wdt_device.gpio)) |
((~tmp) & (1 << mtx1_wdt_device.gpio));
au_writel(tmp, GPIO2_DIR);
if (mtx1_wdt_device.queue && ticks)
mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
else
complete(&mtx1_wdt_device.stop);
spin_unlock(&mtx1_wdt_device.lock);
}
static void mtx1_wdt_reset(void)
{
ticks = mtx1_wdt_device.default_ticks;
}
static void mtx1_wdt_start(void)
{
unsigned long flags;
spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
if (!mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 1;
gpio_set_value(mtx1_wdt_device.gpio, 1);
mod_timer(&mtx1_wdt_device.timer, jiffies + MTX1_WDT_INTERVAL);
}
mtx1_wdt_device.running++;
spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags);
}
static int mtx1_wdt_stop(void)
{
unsigned long flags;
spin_lock_irqsave(&mtx1_wdt_device.lock, flags);
if (mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 0;
gpio_set_value(mtx1_wdt_device.gpio, 0);
}
ticks = mtx1_wdt_device.default_ticks;
spin_unlock_irqrestore(&mtx1_wdt_device.lock, flags);
return 0;
}
/* Filesystem functions */
static int mtx1_wdt_open(struct inode *inode, struct file *file)
{
if (test_and_set_bit(0, &mtx1_wdt_device.inuse))
return -EBUSY;
return nonseekable_open(inode, file);
}
static int mtx1_wdt_release(struct inode *inode, struct file *file)
{
clear_bit(0, &mtx1_wdt_device.inuse);
return 0;
}
static long mtx1_wdt_ioctl(struct file *file, unsigned int cmd,
unsigned long arg)
{
void __user *argp = (void __user *)arg;
int __user *p = (int __user *)argp;
unsigned int value;
static const struct watchdog_info ident = {
.options = WDIOF_CARDRESET,
.identity = "MTX-1 WDT",
};
switch (cmd) {
case WDIOC_GETSUPPORT:
if (copy_to_user(argp, &ident, sizeof(ident)))
return -EFAULT;
break;
case WDIOC_GETSTATUS:
case WDIOC_GETBOOTSTATUS:
put_user(0, p);
break;
case WDIOC_SETOPTIONS:
if (get_user(value, p))
return -EFAULT;
if (value & WDIOS_ENABLECARD)
mtx1_wdt_start();
else if (value & WDIOS_DISABLECARD)
mtx1_wdt_stop();
else
return -EINVAL;
return 0;
case WDIOC_KEEPALIVE:
mtx1_wdt_reset();
break;
default:
return -ENOTTY;
}
return 0;
}
static ssize_t mtx1_wdt_write(struct file *file, const char *buf,
size_t count, loff_t *ppos)
{
if (!count)
return -EIO;
mtx1_wdt_reset();
return count;
}
static const struct file_operations mtx1_wdt_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.unlocked_ioctl = mtx1_wdt_ioctl,
.open = mtx1_wdt_open,
.write = mtx1_wdt_write,
.release = mtx1_wdt_release,
};
static struct miscdevice mtx1_wdt_misc = {
.minor = WATCHDOG_MINOR,
.name = "watchdog",
.fops = &mtx1_wdt_fops,
};
static int __devinit mtx1_wdt_probe(struct platform_device *pdev)
{
int ret;
mtx1_wdt_device.gpio = pdev->resource[0].start;
spin_lock_init(&mtx1_wdt_device.lock);
init_completion(&mtx1_wdt_device.stop);
mtx1_wdt_device.queue = 0;
clear_bit(0, &mtx1_wdt_device.inuse);
setup_timer(&mtx1_wdt_device.timer, mtx1_wdt_trigger, 0L);
mtx1_wdt_device.default_ticks = ticks;
ret = misc_register(&mtx1_wdt_misc);
if (ret < 0) {
printk(KERN_ERR " mtx-1_wdt : failed to register\n");
return ret;
}
mtx1_wdt_start();
printk(KERN_INFO "MTX-1 Watchdog driver\n");
return 0;
}
static int __devexit mtx1_wdt_remove(struct platform_device *pdev)
{
/* FIXME: do we need to lock this test ? */
if (mtx1_wdt_device.queue) {
mtx1_wdt_device.queue = 0;
wait_for_completion(&mtx1_wdt_device.stop);
}
misc_deregister(&mtx1_wdt_misc);
return 0;
}
static struct platform_driver mtx1_wdt = {
.probe = mtx1_wdt_probe,
.remove = __devexit_p(mtx1_wdt_remove),
.driver.name = "mtx1-wdt",
.driver.owner = THIS_MODULE,
};
static int __init mtx1_wdt_init(void)
{
return platform_driver_register(&mtx1_wdt);
}
static void __exit mtx1_wdt_exit(void)
{
platform_driver_unregister(&mtx1_wdt);
}
module_init(mtx1_wdt_init);
module_exit(mtx1_wdt_exit);
MODULE_AUTHOR("Michael Stickel, Florian Fainelli");
MODULE_DESCRIPTION("Driver for the MTX-1 watchdog");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
MODULE_ALIAS("platform:mtx1-wdt");
|
