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
|
/*
* Copyright (C) 2016 National Instruments Corp.
*
* 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.
*
* 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/acpi.h>
#include <linux/bitops.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#define LOCK 0xA5
#define UNLOCK 0x5A
#define WDT_CTRL_RESET_EN BIT(7)
#define WDT_RELOAD_PORT_EN BIT(7)
#define WDT_CTRL 1
#define WDT_RELOAD_CTRL 2
#define WDT_PRESET_PRESCALE 4
#define WDT_REG_LOCK 5
#define WDT_COUNT 6
#define WDT_RELOAD_PORT 7
#define WDT_MIN_TIMEOUT 1
#define WDT_MAX_TIMEOUT 464
#define WDT_DEFAULT_TIMEOUT 80
#define WDT_MAX_COUNTER 15
static unsigned int timeout;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. (default="
__MODULE_STRING(WDT_DEFAULT_TIMEOUT) ")");
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started. (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
struct nic7018_wdt {
u16 io_base;
u32 period;
struct watchdog_device wdd;
};
struct nic7018_config {
u32 period;
u8 divider;
};
static const struct nic7018_config nic7018_configs[] = {
{ 2, 4 },
{ 32, 5 },
};
static inline u32 nic7018_timeout(u32 period, u8 counter)
{
return period * counter - period / 2;
}
static const struct nic7018_config *nic7018_get_config(u32 timeout,
u8 *counter)
{
const struct nic7018_config *config;
u8 count;
if (timeout < 30 && timeout != 16) {
config = &nic7018_configs[0];
count = timeout / 2 + 1;
} else {
config = &nic7018_configs[1];
count = DIV_ROUND_UP(timeout + 16, 32);
if (count > WDT_MAX_COUNTER)
count = WDT_MAX_COUNTER;
}
*counter = count;
return config;
}
static int nic7018_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
const struct nic7018_config *config;
u8 counter;
config = nic7018_get_config(timeout, &counter);
outb(counter << 4 | config->divider,
wdt->io_base + WDT_PRESET_PRESCALE);
wdd->timeout = nic7018_timeout(config->period, counter);
wdt->period = config->period;
return 0;
}
static int nic7018_start(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
u8 control;
nic7018_set_timeout(wdd, wdd->timeout);
control = inb(wdt->io_base + WDT_RELOAD_CTRL);
outb(control | WDT_RELOAD_PORT_EN, wdt->io_base + WDT_RELOAD_CTRL);
outb(1, wdt->io_base + WDT_RELOAD_PORT);
control = inb(wdt->io_base + WDT_CTRL);
outb(control | WDT_CTRL_RESET_EN, wdt->io_base + WDT_CTRL);
return 0;
}
static int nic7018_stop(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
outb(0, wdt->io_base + WDT_CTRL);
outb(0, wdt->io_base + WDT_RELOAD_CTRL);
outb(0xF0, wdt->io_base + WDT_PRESET_PRESCALE);
return 0;
}
static int nic7018_ping(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
outb(1, wdt->io_base + WDT_RELOAD_PORT);
return 0;
}
static unsigned int nic7018_get_timeleft(struct watchdog_device *wdd)
{
struct nic7018_wdt *wdt = watchdog_get_drvdata(wdd);
u8 count;
count = inb(wdt->io_base + WDT_COUNT) & 0xF;
if (!count)
return 0;
return nic7018_timeout(wdt->period, count);
}
static const struct watchdog_info nic7018_wdd_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "NIC7018 Watchdog",
};
static const struct watchdog_ops nic7018_wdd_ops = {
.owner = THIS_MODULE,
.start = nic7018_start,
.stop = nic7018_stop,
.ping = nic7018_ping,
.set_timeout = nic7018_set_timeout,
.get_timeleft = nic7018_get_timeleft,
};
static int nic7018_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct watchdog_device *wdd;
struct nic7018_wdt *wdt;
struct resource *io_rc;
int ret;
wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
platform_set_drvdata(pdev, wdt);
io_rc = platform_get_resource(pdev, IORESOURCE_IO, 0);
if (!io_rc) {
dev_err(dev, "missing IO resources\n");
return -EINVAL;
}
if (!devm_request_region(dev, io_rc->start, resource_size(io_rc),
KBUILD_MODNAME)) {
dev_err(dev, "failed to get IO region\n");
return -EBUSY;
}
wdt->io_base = io_rc->start;
wdd = &wdt->wdd;
wdd->info = &nic7018_wdd_info;
wdd->ops = &nic7018_wdd_ops;
wdd->min_timeout = WDT_MIN_TIMEOUT;
wdd->max_timeout = WDT_MAX_TIMEOUT;
wdd->timeout = WDT_DEFAULT_TIMEOUT;
wdd->parent = dev;
watchdog_set_drvdata(wdd, wdt);
watchdog_set_nowayout(wdd, nowayout);
watchdog_init_timeout(wdd, timeout, dev);
/* Unlock WDT register */
outb(UNLOCK, wdt->io_base + WDT_REG_LOCK);
ret = watchdog_register_device(wdd);
if (ret) {
outb(LOCK, wdt->io_base + WDT_REG_LOCK);
dev_err(dev, "failed to register watchdog\n");
return ret;
}
dev_dbg(dev, "io_base=0x%04X, timeout=%d, nowayout=%d\n",
wdt->io_base, timeout, nowayout);
return 0;
}
static int nic7018_remove(struct platform_device *pdev)
{
struct nic7018_wdt *wdt = platform_get_drvdata(pdev);
watchdog_unregister_device(&wdt->wdd);
/* Lock WDT register */
outb(LOCK, wdt->io_base + WDT_REG_LOCK);
return 0;
}
static const struct acpi_device_id nic7018_device_ids[] = {
{"NIC7018", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, nic7018_device_ids);
static struct platform_driver watchdog_driver = {
.probe = nic7018_probe,
.remove = nic7018_remove,
.driver = {
.name = KBUILD_MODNAME,
.acpi_match_table = ACPI_PTR(nic7018_device_ids),
},
};
module_platform_driver(watchdog_driver);
MODULE_DESCRIPTION("National Instruments NIC7018 Watchdog driver");
MODULE_AUTHOR("Hui Chun Ong <hui.chun.ong@ni.com>");
MODULE_LICENSE("GPL");
|
