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
|
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Congatec Board Controller watchdog driver
*
* Copyright (C) 2024 Bootlin
* Author: Thomas Richard <thomas.richard@bootlin.com>
*/
#include <linux/build_bug.h>
#include <linux/device.h>
#include <linux/limits.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/mfd/cgbc.h>
#define CGBC_WDT_CMD_TRIGGER 0x27
#define CGBC_WDT_CMD_INIT 0x28
#define CGBC_WDT_DISABLE 0x00
#define CGBC_WDT_MODE_SINGLE_EVENT 0x02
#define CGBC_WDT_MIN_TIMEOUT 1
#define CGBC_WDT_MAX_TIMEOUT ((U32_MAX >> 8) / 1000)
#define CGBC_WDT_DEFAULT_TIMEOUT 30
#define CGBC_WDT_DEFAULT_PRETIMEOUT 0
enum action {
ACTION_INT = 0,
ACTION_SMI,
ACTION_RESET,
ACTION_BUTTON,
};
static unsigned int timeout;
module_param(timeout, uint, 0);
MODULE_PARM_DESC(timeout,
"Watchdog timeout in seconds. (>=0, default="
__MODULE_STRING(CGBC_WDT_DEFAULT_TIMEOUT) ")");
static unsigned int pretimeout = CGBC_WDT_DEFAULT_PRETIMEOUT;
module_param(pretimeout, uint, 0);
MODULE_PARM_DESC(pretimeout,
"Watchdog pretimeout in seconds. (>=0, default="
__MODULE_STRING(CGBC_WDT_DEFAULT_PRETIMEOUT) ")");
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 cgbc_wdt_data {
struct cgbc_device_data *cgbc;
struct watchdog_device wdd;
};
struct cgbc_wdt_cmd_cfg {
u8 cmd;
u8 mode;
u8 action;
u8 timeout1[3];
u8 timeout2[3];
u8 reserved[3];
u8 delay[3];
} __packed;
static_assert(sizeof(struct cgbc_wdt_cmd_cfg) == 15);
static int cgbc_wdt_start(struct watchdog_device *wdd)
{
struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd);
struct cgbc_device_data *cgbc = wdt_data->cgbc;
unsigned int timeout1 = (wdd->timeout - wdd->pretimeout) * 1000;
unsigned int timeout2 = wdd->pretimeout * 1000;
u8 action;
struct cgbc_wdt_cmd_cfg cmd_start = {
.cmd = CGBC_WDT_CMD_INIT,
.mode = CGBC_WDT_MODE_SINGLE_EVENT,
.timeout1[0] = (u8)timeout1,
.timeout1[1] = (u8)(timeout1 >> 8),
.timeout1[2] = (u8)(timeout1 >> 16),
.timeout2[0] = (u8)timeout2,
.timeout2[1] = (u8)(timeout2 >> 8),
.timeout2[2] = (u8)(timeout2 >> 16),
};
if (wdd->pretimeout) {
action = 2;
action |= ACTION_SMI << 2;
action |= ACTION_RESET << 4;
} else {
action = 1;
action |= ACTION_RESET << 2;
}
cmd_start.action = action;
return cgbc_command(cgbc, &cmd_start, sizeof(cmd_start), NULL, 0, NULL);
}
static int cgbc_wdt_stop(struct watchdog_device *wdd)
{
struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd);
struct cgbc_device_data *cgbc = wdt_data->cgbc;
struct cgbc_wdt_cmd_cfg cmd_stop = {
.cmd = CGBC_WDT_CMD_INIT,
.mode = CGBC_WDT_DISABLE,
};
return cgbc_command(cgbc, &cmd_stop, sizeof(cmd_stop), NULL, 0, NULL);
}
static int cgbc_wdt_keepalive(struct watchdog_device *wdd)
{
struct cgbc_wdt_data *wdt_data = watchdog_get_drvdata(wdd);
struct cgbc_device_data *cgbc = wdt_data->cgbc;
u8 cmd_ping = CGBC_WDT_CMD_TRIGGER;
return cgbc_command(cgbc, &cmd_ping, sizeof(cmd_ping), NULL, 0, NULL);
}
static int cgbc_wdt_set_pretimeout(struct watchdog_device *wdd,
unsigned int pretimeout)
{
wdd->pretimeout = pretimeout;
if (watchdog_active(wdd))
return cgbc_wdt_start(wdd);
return 0;
}
static int cgbc_wdt_set_timeout(struct watchdog_device *wdd,
unsigned int timeout)
{
if (timeout < wdd->pretimeout)
wdd->pretimeout = 0;
wdd->timeout = timeout;
if (watchdog_active(wdd))
return cgbc_wdt_start(wdd);
return 0;
}
static const struct watchdog_info cgbc_wdt_info = {
.identity = "CGBC Watchdog",
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE | WDIOF_PRETIMEOUT
};
static const struct watchdog_ops cgbc_wdt_ops = {
.owner = THIS_MODULE,
.start = cgbc_wdt_start,
.stop = cgbc_wdt_stop,
.ping = cgbc_wdt_keepalive,
.set_timeout = cgbc_wdt_set_timeout,
.set_pretimeout = cgbc_wdt_set_pretimeout,
};
static int cgbc_wdt_probe(struct platform_device *pdev)
{
struct cgbc_device_data *cgbc = dev_get_drvdata(pdev->dev.parent);
struct device *dev = &pdev->dev;
struct cgbc_wdt_data *wdt_data;
struct watchdog_device *wdd;
wdt_data = devm_kzalloc(dev, sizeof(*wdt_data), GFP_KERNEL);
if (!wdt_data)
return -ENOMEM;
wdt_data->cgbc = cgbc;
wdd = &wdt_data->wdd;
wdd->parent = dev;
wdd->info = &cgbc_wdt_info;
wdd->ops = &cgbc_wdt_ops;
wdd->max_timeout = CGBC_WDT_MAX_TIMEOUT;
wdd->min_timeout = CGBC_WDT_MIN_TIMEOUT;
watchdog_set_drvdata(wdd, wdt_data);
watchdog_set_nowayout(wdd, nowayout);
wdd->timeout = CGBC_WDT_DEFAULT_TIMEOUT;
watchdog_init_timeout(wdd, timeout, dev);
cgbc_wdt_set_pretimeout(wdd, pretimeout);
platform_set_drvdata(pdev, wdt_data);
watchdog_stop_on_reboot(wdd);
watchdog_stop_on_unregister(wdd);
return devm_watchdog_register_device(dev, wdd);
}
static struct platform_driver cgbc_wdt_driver = {
.driver = {
.name = "cgbc-wdt",
},
.probe = cgbc_wdt_probe,
};
module_platform_driver(cgbc_wdt_driver);
MODULE_DESCRIPTION("Congatec Board Controller Watchdog Driver");
MODULE_AUTHOR("Thomas Richard <thomas.richard@bootlin.com>");
MODULE_LICENSE("GPL");
|
