Commit | Line | Data |
---|---|---|
d2912cb1 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
b662f809 DB |
2 | /* |
3 | * The Industrial I/O core, software trigger functions | |
4 | * | |
5 | * Copyright (c) 2015 Intel Corporation | |
b662f809 DB |
6 | */ |
7 | ||
8 | #include <linux/module.h> | |
9 | #include <linux/init.h> | |
10 | #include <linux/kmod.h> | |
11 | #include <linux/list.h> | |
12 | #include <linux/slab.h> | |
13 | ||
14 | #include <linux/iio/sw_trigger.h> | |
8d6c16dd | 15 | #include <linux/iio/configfs.h> |
b662f809 DB |
16 | #include <linux/configfs.h> |
17 | ||
18 | static struct config_group *iio_triggers_group; | |
612a462a | 19 | static const struct config_item_type iio_trigger_type_group_type; |
b662f809 | 20 | |
612a462a | 21 | static const struct config_item_type iio_triggers_group_type = { |
b662f809 DB |
22 | .ct_owner = THIS_MODULE, |
23 | }; | |
24 | ||
25 | static LIST_HEAD(iio_trigger_types_list); | |
26 | static DEFINE_MUTEX(iio_trigger_types_lock); | |
27 | ||
28 | static | |
29 | struct iio_sw_trigger_type *__iio_find_sw_trigger_type(const char *name, | |
abeba59f | 30 | unsigned int len) |
b662f809 DB |
31 | { |
32 | struct iio_sw_trigger_type *t = NULL, *iter; | |
33 | ||
34 | list_for_each_entry(iter, &iio_trigger_types_list, list) | |
35 | if (!strcmp(iter->name, name)) { | |
36 | t = iter; | |
37 | break; | |
38 | } | |
39 | ||
40 | return t; | |
41 | } | |
42 | ||
43 | int iio_register_sw_trigger_type(struct iio_sw_trigger_type *t) | |
44 | { | |
45 | struct iio_sw_trigger_type *iter; | |
46 | int ret = 0; | |
47 | ||
48 | mutex_lock(&iio_trigger_types_lock); | |
49 | iter = __iio_find_sw_trigger_type(t->name, strlen(t->name)); | |
50 | if (iter) | |
51 | ret = -EBUSY; | |
52 | else | |
53 | list_add_tail(&t->list, &iio_trigger_types_list); | |
54 | mutex_unlock(&iio_trigger_types_lock); | |
55 | ||
56 | if (ret) | |
57 | return ret; | |
58 | ||
59 | t->group = configfs_register_default_group(iio_triggers_group, t->name, | |
60 | &iio_trigger_type_group_type); | |
4ad09d95 CZ |
61 | if (IS_ERR(t->group)) { |
62 | mutex_lock(&iio_trigger_types_lock); | |
63 | list_del(&t->list); | |
64 | mutex_unlock(&iio_trigger_types_lock); | |
b662f809 | 65 | ret = PTR_ERR(t->group); |
4ad09d95 | 66 | } |
b662f809 DB |
67 | |
68 | return ret; | |
69 | } | |
70 | EXPORT_SYMBOL(iio_register_sw_trigger_type); | |
71 | ||
72 | void iio_unregister_sw_trigger_type(struct iio_sw_trigger_type *t) | |
73 | { | |
74 | struct iio_sw_trigger_type *iter; | |
75 | ||
76 | mutex_lock(&iio_trigger_types_lock); | |
77 | iter = __iio_find_sw_trigger_type(t->name, strlen(t->name)); | |
78 | if (iter) | |
79 | list_del(&t->list); | |
80 | mutex_unlock(&iio_trigger_types_lock); | |
81 | ||
82 | configfs_unregister_default_group(t->group); | |
83 | } | |
84 | EXPORT_SYMBOL(iio_unregister_sw_trigger_type); | |
85 | ||
86 | static | |
87 | struct iio_sw_trigger_type *iio_get_sw_trigger_type(const char *name) | |
88 | { | |
89 | struct iio_sw_trigger_type *t; | |
90 | ||
91 | mutex_lock(&iio_trigger_types_lock); | |
92 | t = __iio_find_sw_trigger_type(name, strlen(name)); | |
93 | if (t && !try_module_get(t->owner)) | |
94 | t = NULL; | |
95 | mutex_unlock(&iio_trigger_types_lock); | |
96 | ||
97 | return t; | |
98 | } | |
99 | ||
100 | struct iio_sw_trigger *iio_sw_trigger_create(const char *type, const char *name) | |
101 | { | |
102 | struct iio_sw_trigger *t; | |
103 | struct iio_sw_trigger_type *tt; | |
104 | ||
105 | tt = iio_get_sw_trigger_type(type); | |
106 | if (!tt) { | |
107 | pr_err("Invalid trigger type: %s\n", type); | |
108 | return ERR_PTR(-EINVAL); | |
109 | } | |
110 | t = tt->ops->probe(name); | |
111 | if (IS_ERR(t)) | |
112 | goto out_module_put; | |
113 | ||
114 | t->trigger_type = tt; | |
115 | ||
116 | return t; | |
117 | out_module_put: | |
118 | module_put(tt->owner); | |
119 | return t; | |
120 | } | |
121 | EXPORT_SYMBOL(iio_sw_trigger_create); | |
122 | ||
123 | void iio_sw_trigger_destroy(struct iio_sw_trigger *t) | |
124 | { | |
125 | struct iio_sw_trigger_type *tt = t->trigger_type; | |
126 | ||
127 | tt->ops->remove(t); | |
128 | module_put(tt->owner); | |
129 | } | |
130 | EXPORT_SYMBOL(iio_sw_trigger_destroy); | |
131 | ||
132 | static struct config_group *trigger_make_group(struct config_group *group, | |
133 | const char *name) | |
134 | { | |
135 | struct iio_sw_trigger *t; | |
136 | ||
137 | t = iio_sw_trigger_create(group->cg_item.ci_name, name); | |
138 | if (IS_ERR(t)) | |
139 | return ERR_CAST(t); | |
140 | ||
141 | config_item_set_name(&t->group.cg_item, "%s", name); | |
142 | ||
143 | return &t->group; | |
144 | } | |
145 | ||
146 | static void trigger_drop_group(struct config_group *group, | |
147 | struct config_item *item) | |
148 | { | |
149 | struct iio_sw_trigger *t = to_iio_sw_trigger(item); | |
150 | ||
151 | iio_sw_trigger_destroy(t); | |
152 | config_item_put(item); | |
153 | } | |
154 | ||
155 | static struct configfs_group_operations trigger_ops = { | |
156 | .make_group = &trigger_make_group, | |
157 | .drop_item = &trigger_drop_group, | |
158 | }; | |
159 | ||
612a462a | 160 | static const struct config_item_type iio_trigger_type_group_type = { |
b662f809 DB |
161 | .ct_group_ops = &trigger_ops, |
162 | .ct_owner = THIS_MODULE, | |
163 | }; | |
164 | ||
165 | static int __init iio_sw_trigger_init(void) | |
166 | { | |
167 | iio_triggers_group = | |
168 | configfs_register_default_group(&iio_configfs_subsys.su_group, | |
169 | "triggers", | |
170 | &iio_triggers_group_type); | |
f9ed89e1 | 171 | return PTR_ERR_OR_ZERO(iio_triggers_group); |
b662f809 DB |
172 | } |
173 | module_init(iio_sw_trigger_init); | |
174 | ||
175 | static void __exit iio_sw_trigger_exit(void) | |
176 | { | |
177 | configfs_unregister_default_group(iio_triggers_group); | |
178 | } | |
179 | module_exit(iio_sw_trigger_exit); | |
180 | ||
181 | MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>"); | |
182 | MODULE_DESCRIPTION("Industrial I/O software triggers support"); | |
183 | MODULE_LICENSE("GPL v2"); |