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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_device.h>
15#include <linux/iio/configfs.h>
16#include <linux/configfs.h>
17
18static struct config_group *iio_devices_group;
19static const struct config_item_type iio_device_type_group_type;
20
21static const struct config_item_type iio_devices_group_type = {
22 .ct_owner = THIS_MODULE,
23};
24
25static LIST_HEAD(iio_device_types_list);
26static DEFINE_MUTEX(iio_device_types_lock);
27
28static
29struct iio_sw_device_type *__iio_find_sw_device_type(const char *name,
30 unsigned len)
31{
32 struct iio_sw_device_type *d = NULL, *iter;
33
34 list_for_each_entry(iter, &iio_device_types_list, list)
35 if (!strcmp(iter->name, name)) {
36 d = iter;
37 break;
38 }
39
40 return d;
41}
42
43int iio_register_sw_device_type(struct iio_sw_device_type *d)
44{
45 struct iio_sw_device_type *iter;
46 int ret = 0;
47
48 mutex_lock(&iio_device_types_lock);
49 iter = __iio_find_sw_device_type(d->name, strlen(d->name));
50 if (iter)
51 ret = -EBUSY;
52 else
53 list_add_tail(&d->list, &iio_device_types_list);
54 mutex_unlock(&iio_device_types_lock);
55
56 if (ret)
57 return ret;
58
59 d->group = configfs_register_default_group(iio_devices_group, d->name,
60 &iio_device_type_group_type);
61 if (IS_ERR(d->group))
62 ret = PTR_ERR(d->group);
63
64 return ret;
65}
66EXPORT_SYMBOL(iio_register_sw_device_type);
67
68void iio_unregister_sw_device_type(struct iio_sw_device_type *dt)
69{
70 struct iio_sw_device_type *iter;
71
72 mutex_lock(&iio_device_types_lock);
73 iter = __iio_find_sw_device_type(dt->name, strlen(dt->name));
74 if (iter)
75 list_del(&dt->list);
76 mutex_unlock(&iio_device_types_lock);
77
78 configfs_unregister_default_group(dt->group);
79}
80EXPORT_SYMBOL(iio_unregister_sw_device_type);
81
82static
83struct iio_sw_device_type *iio_get_sw_device_type(const char *name)
84{
85 struct iio_sw_device_type *dt;
86
87 mutex_lock(&iio_device_types_lock);
88 dt = __iio_find_sw_device_type(name, strlen(name));
89 if (dt && !try_module_get(dt->owner))
90 dt = NULL;
91 mutex_unlock(&iio_device_types_lock);
92
93 return dt;
94}
95
96struct iio_sw_device *iio_sw_device_create(const char *type, const char *name)
97{
98 struct iio_sw_device *d;
99 struct iio_sw_device_type *dt;
100
101 dt = iio_get_sw_device_type(type);
102 if (!dt) {
103 pr_err("Invalid device type: %s\n", type);
104 return ERR_PTR(-EINVAL);
105 }
106 d = dt->ops->probe(name);
107 if (IS_ERR(d))
108 goto out_module_put;
109
110 d->device_type = dt;
111
112 return d;
113out_module_put:
114 module_put(dt->owner);
115 return d;
116}
117EXPORT_SYMBOL(iio_sw_device_create);
118
119void iio_sw_device_destroy(struct iio_sw_device *d)
120{
121 struct iio_sw_device_type *dt = d->device_type;
122
123 dt->ops->remove(d);
124 module_put(dt->owner);
125}
126EXPORT_SYMBOL(iio_sw_device_destroy);
127
128static struct config_group *device_make_group(struct config_group *group,
129 const char *name)
130{
131 struct iio_sw_device *d;
132
133 d = iio_sw_device_create(group->cg_item.ci_name, name);
134 if (IS_ERR(d))
135 return ERR_CAST(d);
136
137 config_item_set_name(&d->group.cg_item, "%s", name);
138
139 return &d->group;
140}
141
142static void device_drop_group(struct config_group *group,
143 struct config_item *item)
144{
145 struct iio_sw_device *d = to_iio_sw_device(item);
146
147 iio_sw_device_destroy(d);
148 config_item_put(item);
149}
150
151static struct configfs_group_operations device_ops = {
152 .make_group = &device_make_group,
153 .drop_item = &device_drop_group,
154};
155
156static const struct config_item_type iio_device_type_group_type = {
157 .ct_group_ops = &device_ops,
158 .ct_owner = THIS_MODULE,
159};
160
161static int __init iio_sw_device_init(void)
162{
163 iio_devices_group =
164 configfs_register_default_group(&iio_configfs_subsys.su_group,
165 "devices",
166 &iio_devices_group_type);
167 return PTR_ERR_OR_ZERO(iio_devices_group);
168}
169module_init(iio_sw_device_init);
170
171static void __exit iio_sw_device_exit(void)
172{
173 configfs_unregister_default_group(iio_devices_group);
174}
175module_exit(iio_sw_device_exit);
176
177MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>");
178MODULE_DESCRIPTION("Industrial I/O software devices support");
179MODULE_LICENSE("GPL v2");
180
