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
|
/*
* The Industrial I/O core, software trigger functions
*
* Copyright (c) 2015 Intel Corporation
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kmod.h>
#include <linux/list.h>
#include <linux/slab.h>
#include <linux/iio/sw_trigger.h>
#include <linux/configfs.h>
static struct config_group *iio_triggers_group;
static struct config_item_type iio_trigger_type_group_type;
static struct config_item_type iio_triggers_group_type = {
.ct_owner = THIS_MODULE,
};
static LIST_HEAD(iio_trigger_types_list);
static DEFINE_MUTEX(iio_trigger_types_lock);
static
struct iio_sw_trigger_type *__iio_find_sw_trigger_type(const char *name,
unsigned len)
{
struct iio_sw_trigger_type *t = NULL, *iter;
list_for_each_entry(iter, &iio_trigger_types_list, list)
if (!strcmp(iter->name, name)) {
t = iter;
break;
}
return t;
}
int iio_register_sw_trigger_type(struct iio_sw_trigger_type *t)
{
struct iio_sw_trigger_type *iter;
int ret = 0;
mutex_lock(&iio_trigger_types_lock);
iter = __iio_find_sw_trigger_type(t->name, strlen(t->name));
if (iter)
ret = -EBUSY;
else
list_add_tail(&t->list, &iio_trigger_types_list);
mutex_unlock(&iio_trigger_types_lock);
if (ret)
return ret;
t->group = configfs_register_default_group(iio_triggers_group, t->name,
&iio_trigger_type_group_type);
if (IS_ERR(t->group))
ret = PTR_ERR(t->group);
return ret;
}
EXPORT_SYMBOL(iio_register_sw_trigger_type);
void iio_unregister_sw_trigger_type(struct iio_sw_trigger_type *t)
{
struct iio_sw_trigger_type *iter;
mutex_lock(&iio_trigger_types_lock);
iter = __iio_find_sw_trigger_type(t->name, strlen(t->name));
if (iter)
list_del(&t->list);
mutex_unlock(&iio_trigger_types_lock);
configfs_unregister_default_group(t->group);
}
EXPORT_SYMBOL(iio_unregister_sw_trigger_type);
static
struct iio_sw_trigger_type *iio_get_sw_trigger_type(const char *name)
{
struct iio_sw_trigger_type *t;
mutex_lock(&iio_trigger_types_lock);
t = __iio_find_sw_trigger_type(name, strlen(name));
if (t && !try_module_get(t->owner))
t = NULL;
mutex_unlock(&iio_trigger_types_lock);
return t;
}
struct iio_sw_trigger *iio_sw_trigger_create(const char *type, const char *name)
{
struct iio_sw_trigger *t;
struct iio_sw_trigger_type *tt;
tt = iio_get_sw_trigger_type(type);
if (!tt) {
pr_err("Invalid trigger type: %s\n", type);
return ERR_PTR(-EINVAL);
}
t = tt->ops->probe(name);
if (IS_ERR(t))
goto out_module_put;
t->trigger_type = tt;
return t;
out_module_put:
module_put(tt->owner);
return t;
}
EXPORT_SYMBOL(iio_sw_trigger_create);
void iio_sw_trigger_destroy(struct iio_sw_trigger *t)
{
struct iio_sw_trigger_type *tt = t->trigger_type;
tt->ops->remove(t);
module_put(tt->owner);
}
EXPORT_SYMBOL(iio_sw_trigger_destroy);
static struct config_group *trigger_make_group(struct config_group *group,
const char *name)
{
struct iio_sw_trigger *t;
t = iio_sw_trigger_create(group->cg_item.ci_name, name);
if (IS_ERR(t))
return ERR_CAST(t);
config_item_set_name(&t->group.cg_item, "%s", name);
return &t->group;
}
static void trigger_drop_group(struct config_group *group,
struct config_item *item)
{
struct iio_sw_trigger *t = to_iio_sw_trigger(item);
iio_sw_trigger_destroy(t);
config_item_put(item);
}
static struct configfs_group_operations trigger_ops = {
.make_group = &trigger_make_group,
.drop_item = &trigger_drop_group,
};
static struct config_item_type iio_trigger_type_group_type = {
.ct_group_ops = &trigger_ops,
.ct_owner = THIS_MODULE,
};
static int __init iio_sw_trigger_init(void)
{
iio_triggers_group =
configfs_register_default_group(&iio_configfs_subsys.su_group,
"triggers",
&iio_triggers_group_type);
if (IS_ERR(iio_triggers_group))
return PTR_ERR(iio_triggers_group);
return 0;
}
module_init(iio_sw_trigger_init);
static void __exit iio_sw_trigger_exit(void)
{
configfs_unregister_default_group(iio_triggers_group);
}
module_exit(iio_sw_trigger_exit);
MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
MODULE_DESCRIPTION("Industrial I/O software triggers support");
MODULE_LICENSE("GPL v2");
|
