1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __GADGET_CONFIGFS__
3 #define __GADGET_CONFIGFS__
4 
5 #include <linux/configfs.h>
6 
7 int check_user_usb_string(const char *name,
8 		struct usb_gadget_strings *stringtab_dev);
9 
10 #define GS_STRINGS_W(__struct, __name)	\
11 static ssize_t __struct##_##__name##_store(struct config_item *item, \
12 		const char *page, size_t len)		\
13 {							\
14 	struct __struct *gs = to_##__struct(item);	\
15 	int ret;					\
16 							\
17 	ret = usb_string_copy(page, &gs->__name);	\
18 	if (ret)					\
19 		return ret;				\
20 	return len;					\
21 }
22 
23 #define GS_STRINGS_R(__struct, __name)	\
24 static ssize_t __struct##_##__name##_show(struct config_item *item, char *page) \
25 {	\
26 	struct __struct *gs = to_##__struct(item);	\
27 	return sprintf(page, "%s\n", gs->__name ?: "");	\
28 }
29 
30 #define GS_STRINGS_RW(struct_name, _name)	\
31 	GS_STRINGS_R(struct_name, _name)	\
32 	GS_STRINGS_W(struct_name, _name)	\
33 	CONFIGFS_ATTR(struct_name##_, _name)
34 
35 #define USB_CONFIG_STRING_RW_OPS(struct_in)				\
36 static struct configfs_item_operations struct_in##_langid_item_ops = {	\
37 	.release                = struct_in##_attr_release,		\
38 };									\
39 									\
40 static struct config_item_type struct_in##_langid_type = {		\
41 	.ct_item_ops	= &struct_in##_langid_item_ops,			\
42 	.ct_attrs	= struct_in##_langid_attrs,			\
43 	.ct_owner	= THIS_MODULE,					\
44 }
45 
46 #define USB_CONFIG_STRINGS_LANG(struct_in, struct_member)	\
47 	static struct config_group *struct_in##_strings_make(		\
48 			struct config_group *group,			\
49 			const char *name)				\
50 	{								\
51 	struct struct_member *gi;					\
52 	struct struct_in *gs;						\
53 	struct struct_in *new;						\
54 	int langs = 0;							\
55 	int ret;							\
56 									\
57 	new = kzalloc(sizeof(*new), GFP_KERNEL);			\
58 	if (!new)							\
59 		return ERR_PTR(-ENOMEM);				\
60 									\
61 	ret = check_user_usb_string(name, &new->stringtab_dev);		\
62 	if (ret)							\
63 		goto err;						\
64 	config_group_init_type_name(&new->group, name,			\
65 			&struct_in##_langid_type);			\
66 									\
67 	gi = container_of(group, struct struct_member, strings_group);	\
68 	ret = -EEXIST;							\
69 	list_for_each_entry(gs, &gi->string_list, list) {		\
70 		if (gs->stringtab_dev.language == new->stringtab_dev.language) \
71 			goto err;					\
72 		langs++;						\
73 	}								\
74 	ret = -EOVERFLOW;						\
75 	if (langs >= MAX_USB_STRING_LANGS)				\
76 		goto err;						\
77 									\
78 	list_add_tail(&new->list, &gi->string_list);			\
79 	return &new->group;						\
80 err:									\
81 	kfree(new);							\
82 	return ERR_PTR(ret);						\
83 }									\
84 									\
85 static void struct_in##_strings_drop(					\
86 		struct config_group *group,				\
87 		struct config_item *item)				\
88 {									\
89 	config_item_put(item);						\
90 }									\
91 									\
92 static struct configfs_group_operations struct_in##_strings_ops = {	\
93 	.make_group     = &struct_in##_strings_make,			\
94 	.drop_item      = &struct_in##_strings_drop,			\
95 };									\
96 									\
97 static struct config_item_type struct_in##_strings_type = {		\
98 	.ct_group_ops   = &struct_in##_strings_ops,			\
99 	.ct_owner       = THIS_MODULE,					\
100 }
101 
102 #endif
103