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
|
/*
* Copyright (c) 2016 Yang Ling <gnaygnil@gmail.com>
*
* 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.
*/
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <loongson1.h>
#define DEFAULT_HEARTBEAT 30
static bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0444);
static unsigned int heartbeat;
module_param(heartbeat, uint, 0444);
struct ls1x_wdt_drvdata {
void __iomem *base;
struct clk *clk;
unsigned long clk_rate;
struct watchdog_device wdt;
};
static int ls1x_wdt_ping(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x1, drvdata->base + WDT_SET);
return 0;
}
static int ls1x_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int timeout)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
unsigned int max_hw_heartbeat = wdt_dev->max_hw_heartbeat_ms / 1000;
unsigned int counts;
wdt_dev->timeout = timeout;
counts = drvdata->clk_rate * min(timeout, max_hw_heartbeat);
writel(counts, drvdata->base + WDT_TIMER);
return 0;
}
static int ls1x_wdt_start(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x1, drvdata->base + WDT_EN);
return 0;
}
static int ls1x_wdt_stop(struct watchdog_device *wdt_dev)
{
struct ls1x_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
writel(0x0, drvdata->base + WDT_EN);
return 0;
}
static const struct watchdog_info ls1x_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "Loongson1 Watchdog",
};
static const struct watchdog_ops ls1x_wdt_ops = {
.owner = THIS_MODULE,
.start = ls1x_wdt_start,
.stop = ls1x_wdt_stop,
.ping = ls1x_wdt_ping,
.set_timeout = ls1x_wdt_set_timeout,
};
static int ls1x_wdt_probe(struct platform_device *pdev)
{
struct ls1x_wdt_drvdata *drvdata;
struct watchdog_device *ls1x_wdt;
unsigned long clk_rate;
struct resource *res;
int err;
drvdata = devm_kzalloc(&pdev->dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
drvdata->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(drvdata->base))
return PTR_ERR(drvdata->base);
drvdata->clk = devm_clk_get(&pdev->dev, pdev->name);
if (IS_ERR(drvdata->clk))
return PTR_ERR(drvdata->clk);
err = clk_prepare_enable(drvdata->clk);
if (err) {
dev_err(&pdev->dev, "clk enable failed\n");
return err;
}
clk_rate = clk_get_rate(drvdata->clk);
if (!clk_rate) {
err = -EINVAL;
goto err0;
}
drvdata->clk_rate = clk_rate;
ls1x_wdt = &drvdata->wdt;
ls1x_wdt->info = &ls1x_wdt_info;
ls1x_wdt->ops = &ls1x_wdt_ops;
ls1x_wdt->timeout = DEFAULT_HEARTBEAT;
ls1x_wdt->min_timeout = 1;
ls1x_wdt->max_hw_heartbeat_ms = U32_MAX / clk_rate * 1000;
ls1x_wdt->parent = &pdev->dev;
watchdog_init_timeout(ls1x_wdt, heartbeat, &pdev->dev);
watchdog_set_nowayout(ls1x_wdt, nowayout);
watchdog_set_drvdata(ls1x_wdt, drvdata);
err = watchdog_register_device(&drvdata->wdt);
if (err) {
dev_err(&pdev->dev, "failed to register watchdog device\n");
goto err0;
}
platform_set_drvdata(pdev, drvdata);
dev_info(&pdev->dev, "Loongson1 Watchdog driver registered\n");
return 0;
err0:
clk_disable_unprepare(drvdata->clk);
return err;
}
static int ls1x_wdt_remove(struct platform_device *pdev)
{
struct ls1x_wdt_drvdata *drvdata = platform_get_drvdata(pdev);
watchdog_unregister_device(&drvdata->wdt);
clk_disable_unprepare(drvdata->clk);
return 0;
}
static struct platform_driver ls1x_wdt_driver = {
.probe = ls1x_wdt_probe,
.remove = ls1x_wdt_remove,
.driver = {
.name = "ls1x-wdt",
},
};
module_platform_driver(ls1x_wdt_driver);
MODULE_AUTHOR("Yang Ling <gnaygnil@gmail.com>");
MODULE_DESCRIPTION("Loongson1 Watchdog Driver");
MODULE_LICENSE("GPL");
|
