1 files changed, 110 insertions, 0 deletions
diff --git a/include/linux/usb/gadget_configfs.h b/include/linux/usb/gadget_configfs.h
new file mode 100644
index 000000000000..d74c0ae989d5
--- /dev/null
+++ b/include/linux/usb/gadget_configfs.h
@@ -0,0 +1,110 @@
+#ifndef __GADGET_CONFIGFS__
+#define __GADGET_CONFIGFS__
+
+#include <linux/configfs.h>
+
+int check_user_usb_string(const char *name,
+		struct usb_gadget_strings *stringtab_dev);
+
+#define GS_STRINGS_W(__struct, __name)	\
+	static ssize_t __struct##_##__name##_store(struct __struct *gs, \
+		const char *page, size_t len)		\
+{							\
+	int ret;					\
+							\
+	ret = usb_string_copy(page, &gs->__name);	\
+	if (ret)					\
+		return ret;				\
+	return len;					\
+}
+
+#define GS_STRINGS_R(__struct, __name)	\
+	static ssize_t __struct##_##__name##_show(struct __struct *gs, \
+			char *page)	\
+{	\
+	return sprintf(page, "%s\n", gs->__name ?: "");	\
+}
+
+#define GS_STRING_ITEM_ATTR(struct_name, name)	\
+	static struct struct_name##_attribute struct_name##_##name = \
+		__CONFIGFS_ATTR(name,  S_IRUGO | S_IWUSR,		\
+				struct_name##_##name##_show,		\
+				struct_name##_##name##_store)
+
+#define GS_STRINGS_RW(struct_name, _name)	\
+	GS_STRINGS_R(struct_name, _name)	\
+	GS_STRINGS_W(struct_name, _name)	\
+	GS_STRING_ITEM_ATTR(struct_name, _name)
+
+#define USB_CONFIG_STRING_RW_OPS(struct_in)				\
+	CONFIGFS_ATTR_OPS(struct_in);					\
+									\
+static struct configfs_item_operations struct_in##_langid_item_ops = {	\
+	.release                = struct_in##_attr_release,		\
+	.show_attribute         = struct_in##_attr_show,		\
+	.store_attribute        = struct_in##_attr_store,		\
+};									\
+									\
+static struct config_item_type struct_in##_langid_type = {		\
+	.ct_item_ops	= &struct_in##_langid_item_ops,			\
+	.ct_attrs	= struct_in##_langid_attrs,			\
+	.ct_owner	= THIS_MODULE,					\
+}
+
+#define USB_CONFIG_STRINGS_LANG(struct_in, struct_member)	\
+	static struct config_group *struct_in##_strings_make(		\
+			struct config_group *group,			\
+			const char *name)				\
+	{								\
+	struct struct_member *gi;					\
+	struct struct_in *gs;						\
+	struct struct_in *new;						\
+	int langs = 0;							\
+	int ret;							\
+									\
+	new = kzalloc(sizeof(*new), GFP_KERNEL);			\
+	if (!new)							\
+		return ERR_PTR(-ENOMEM);				\
+									\
+	ret = check_user_usb_string(name, &new->stringtab_dev);		\
+	if (ret)							\
+		goto err;						\
+	config_group_init_type_name(&new->group, name,			\
+			&struct_in##_langid_type);			\
+									\
+	gi = container_of(group, struct struct_member, strings_group);	\
+	ret = -EEXIST;							\
+	list_for_each_entry(gs, &gi->string_list, list) {		\
+		if (gs->stringtab_dev.language == new->stringtab_dev.language) \
+			goto err;					\
+		langs++;						\
+	}								\
+	ret = -EOVERFLOW;						\
+	if (langs >= MAX_USB_STRING_LANGS)				\
+		goto err;						\
+									\
+	list_add_tail(&new->list, &gi->string_list);			\
+	return &new->group;						\
+err:									\
+	kfree(new);							\
+	return ERR_PTR(ret);						\
+}									\
+									\
+static void struct_in##_strings_drop(					\
+		struct config_group *group,				\
+		struct config_item *item)				\
+{									\
+	config_item_put(item);						\
+}									\
+									\
+static struct configfs_group_operations struct_in##_strings_ops = {	\
+	.make_group     = &struct_in##_strings_make,			\
+	.drop_item      = &struct_in##_strings_drop,			\
+};									\
+									\
+static struct config_item_type struct_in##_strings_type = {		\
+	.ct_group_ops   = &struct_in##_strings_ops,			\
+	.ct_owner       = THIS_MODULE,					\
+}
+
+#endif