diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
new file mode 100644
index 0000000..7d39ff4
--- /dev/null
+++ b/scripts/kconfig/expr.h
@@ -0,0 +1,195 @@
+/*
+ * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
+ * Released under the terms of the GNU GPL v2.0.
+ */
+
+#ifndef EXPR_H
+#define EXPR_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdio.h>
+#ifndef __cplusplus
+#include <stdbool.h>
+#endif
+
+struct file {
+	struct file *next;
+	struct file *parent;
+	char *name;
+	int lineno;
+	int flags;
+};
+
+#define FILE_BUSY		0x0001
+#define FILE_SCANNED		0x0002
+#define FILE_PRINTED		0x0004
+
+typedef enum tristate {
+	no, mod, yes
+} tristate;
+
+enum expr_type {
+	E_NONE, E_OR, E_AND, E_NOT, E_EQUAL, E_UNEQUAL, E_CHOICE, E_SYMBOL, E_RANGE
+};
+
+union expr_data {
+	struct expr *expr;
+	struct symbol *sym;
+};
+
+struct expr {
+	enum expr_type type;
+	union expr_data left, right;
+};
+
+#define E_OR(dep1, dep2)	(((dep1)>(dep2))?(dep1):(dep2))
+#define E_AND(dep1, dep2)	(((dep1)<(dep2))?(dep1):(dep2))
+#define E_NOT(dep)		(2-(dep))
+
+struct expr_value {
+	struct expr *expr;
+	tristate tri;
+};
+
+struct symbol_value {
+	void *val;
+	tristate tri;
+};
+
+enum symbol_type {
+	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING, S_OTHER
+};
+
+struct symbol {
+	struct symbol *next;
+	char *name;
+	char *help;
+	enum symbol_type type;
+	struct symbol_value curr, user;
+	tristate visible;
+	int flags;
+	struct property *prop;
+	struct expr *dep, *dep2;
+	struct expr_value rev_dep;
+};
+
+#define for_all_symbols(i, sym) for (i = 0; i < 257; i++) for (sym = symbol_hash[i]; sym; sym = sym->next) if (sym->type != S_OTHER)
+
+#define SYMBOL_YES		0x0001
+#define SYMBOL_MOD		0x0002
+#define SYMBOL_NO		0x0004
+#define SYMBOL_CONST		0x0007
+#define SYMBOL_CHECK		0x0008
+#define SYMBOL_CHOICE		0x0010
+#define SYMBOL_CHOICEVAL	0x0020
+#define SYMBOL_PRINTED		0x0040
+#define SYMBOL_VALID		0x0080
+#define SYMBOL_OPTIONAL		0x0100
+#define SYMBOL_WRITE		0x0200
+#define SYMBOL_CHANGED		0x0400
+#define SYMBOL_NEW		0x0800
+#define SYMBOL_AUTO		0x1000
+#define SYMBOL_CHECKED		0x2000
+#define SYMBOL_CHECK_DONE	0x4000
+#define SYMBOL_WARNED		0x8000
+
+#define SYMBOL_MAXLENGTH	256
+#define SYMBOL_HASHSIZE		257
+#define SYMBOL_HASHMASK		0xff
+
+enum prop_type {
+	P_UNKNOWN, P_PROMPT, P_COMMENT, P_MENU, P_DEFAULT, P_CHOICE, P_SELECT, P_RANGE
+};
+
+struct property {
+	struct property *next;
+	struct symbol *sym;
+	enum prop_type type;
+	const char *text;
+	struct expr_value visible;
+	struct expr *expr;
+	struct menu *menu;
+	struct file *file;
+	int lineno;
+};
+
+#define for_all_properties(sym, st, tok) \
+	for (st = sym->prop; st; st = st->next) \
+		if (st->type == (tok))
+#define for_all_defaults(sym, st) for_all_properties(sym, st, P_DEFAULT)
+#define for_all_choices(sym, st) for_all_properties(sym, st, P_CHOICE)
+#define for_all_prompts(sym, st) \
+	for (st = sym->prop; st; st = st->next) \
+		if (st->text)
+
+struct menu {
+	struct menu *next;
+	struct menu *parent;
+	struct menu *list;
+	struct symbol *sym;
+	struct property *prompt;
+	struct expr *dep;
+	unsigned int flags;
+	//char *help;
+	struct file *file;
+	int lineno;
+	void *data;
+};
+
+#define MENU_CHANGED		0x0001
+#define MENU_ROOT		0x0002
+
+#ifndef SWIG
+
+extern struct file *file_list;
+extern struct file *current_file;
+struct file *lookup_file(const char *name);
+
+extern struct symbol symbol_yes, symbol_no, symbol_mod;
+extern struct symbol *modules_sym;
+extern int cdebug;
+struct expr *expr_alloc_symbol(struct symbol *sym);
+struct expr *expr_alloc_one(enum expr_type type, struct expr *ce);
+struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2);
+struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
+struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
+struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
+struct expr *expr_copy(struct expr *org);
+void expr_free(struct expr *e);
+int expr_eq(struct expr *e1, struct expr *e2);
+void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
+tristate expr_calc_value(struct expr *e);
+struct expr *expr_eliminate_yn(struct expr *e);
+struct expr *expr_trans_bool(struct expr *e);
+struct expr *expr_eliminate_dups(struct expr *e);
+struct expr *expr_transform(struct expr *e);
+int expr_contains_symbol(struct expr *dep, struct symbol *sym);
+bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
+struct expr *expr_extract_eq_and(struct expr **ep1, struct expr **ep2);
+struct expr *expr_extract_eq_or(struct expr **ep1, struct expr **ep2);
+void expr_extract_eq(enum expr_type type, struct expr **ep, struct expr **ep1, struct expr **ep2);
+struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
+
+void expr_fprint(struct expr *e, FILE *out);
+struct gstr; /* forward */
+void expr_gstr_print(struct expr *e, struct gstr *gs);
+
+static inline int expr_is_yes(struct expr *e)
+{
+	return !e || (e->type == E_SYMBOL && e->left.sym == &symbol_yes);
+}
+
+static inline int expr_is_no(struct expr *e)
+{
+	return e && (e->type == E_SYMBOL && e->left.sym == &symbol_no);
+}
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* EXPR_H */