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
|
/*
* Retu watchdog driver
*
* Copyright (C) 2004, 2005 Nokia Corporation
*
* Based on code written by Amit Kucheria and Michael Buesch.
* Rewritten by Aaro Koskinen.
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file "COPYING" in the main directory of this
* archive for more details.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mfd/retu.h>
#include <linux/watchdog.h>
#include <linux/platform_device.h>
/* Watchdog timer values in seconds */
#define RETU_WDT_MAX_TIMER 63
struct retu_wdt_dev {
struct retu_dev *rdev;
struct device *dev;
struct delayed_work ping_work;
};
/*
* Since Retu watchdog cannot be disabled in hardware, we must kick it
* with a timer until userspace watchdog software takes over. If
* CONFIG_WATCHDOG_NOWAYOUT is set, we never start the feeding.
*/
static void retu_wdt_ping_enable(struct retu_wdt_dev *wdev)
{
retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER);
schedule_delayed_work(&wdev->ping_work,
round_jiffies_relative(RETU_WDT_MAX_TIMER * HZ / 2));
}
static void retu_wdt_ping_disable(struct retu_wdt_dev *wdev)
{
retu_write(wdev->rdev, RETU_REG_WATCHDOG, RETU_WDT_MAX_TIMER);
cancel_delayed_work_sync(&wdev->ping_work);
}
static void retu_wdt_ping_work(struct work_struct *work)
{
struct retu_wdt_dev *wdev = container_of(to_delayed_work(work),
struct retu_wdt_dev, ping_work);
retu_wdt_ping_enable(wdev);
}
static int retu_wdt_start(struct watchdog_device *wdog)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
retu_wdt_ping_disable(wdev);
return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
}
static int retu_wdt_stop(struct watchdog_device *wdog)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
retu_wdt_ping_enable(wdev);
return 0;
}
static int retu_wdt_ping(struct watchdog_device *wdog)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
}
static int retu_wdt_set_timeout(struct watchdog_device *wdog,
unsigned int timeout)
{
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
wdog->timeout = timeout;
return retu_write(wdev->rdev, RETU_REG_WATCHDOG, wdog->timeout);
}
static const struct watchdog_info retu_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
.identity = "Retu watchdog",
};
static const struct watchdog_ops retu_wdt_ops = {
.owner = THIS_MODULE,
.start = retu_wdt_start,
.stop = retu_wdt_stop,
.ping = retu_wdt_ping,
.set_timeout = retu_wdt_set_timeout,
};
static int retu_wdt_probe(struct platform_device *pdev)
{
struct retu_dev *rdev = dev_get_drvdata(pdev->dev.parent);
bool nowayout = WATCHDOG_NOWAYOUT;
struct watchdog_device *retu_wdt;
struct retu_wdt_dev *wdev;
int ret;
retu_wdt = devm_kzalloc(&pdev->dev, sizeof(*retu_wdt), GFP_KERNEL);
if (!retu_wdt)
return -ENOMEM;
wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL);
if (!wdev)
return -ENOMEM;
retu_wdt->info = &retu_wdt_info;
retu_wdt->ops = &retu_wdt_ops;
retu_wdt->timeout = RETU_WDT_MAX_TIMER;
retu_wdt->min_timeout = 0;
retu_wdt->max_timeout = RETU_WDT_MAX_TIMER;
watchdog_set_drvdata(retu_wdt, wdev);
watchdog_set_nowayout(retu_wdt, nowayout);
wdev->rdev = rdev;
wdev->dev = &pdev->dev;
INIT_DELAYED_WORK(&wdev->ping_work, retu_wdt_ping_work);
ret = watchdog_register_device(retu_wdt);
if (ret < 0)
return ret;
if (nowayout)
retu_wdt_ping(retu_wdt);
else
retu_wdt_ping_enable(wdev);
platform_set_drvdata(pdev, retu_wdt);
return 0;
}
static int retu_wdt_remove(struct platform_device *pdev)
{
struct watchdog_device *wdog = platform_get_drvdata(pdev);
struct retu_wdt_dev *wdev = watchdog_get_drvdata(wdog);
watchdog_unregister_device(wdog);
cancel_delayed_work_sync(&wdev->ping_work);
return 0;
}
static struct platform_driver retu_wdt_driver = {
.probe = retu_wdt_probe,
.remove = retu_wdt_remove,
.driver = {
.name = "retu-wdt",
},
};
module_platform_driver(retu_wdt_driver);
MODULE_ALIAS("platform:retu-wdt");
MODULE_DESCRIPTION("Retu watchdog");
MODULE_AUTHOR("Amit Kucheria");
MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
MODULE_LICENSE("GPL");
|
