1 files changed, 54 insertions, 28 deletions

diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 9d4cba1c001d..6408fefae083 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -65,9 +65,13 @@ enum symbol_type {
         S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING, S_OTHER
 };
 
+/* enum values are used as index to symbol.def[] */
 enum {
         S_DEF_USER,             /* main user value */
-        S_DEF_AUTO,
+        S_DEF_AUTO,             /* values read from auto.conf */
+        S_DEF_DEF3,             /* Reserved for UI usage */
+        S_DEF_DEF4,             /* Reserved for UI usage */
+        S_DEF_COUNT
 };
 
 struct symbol {
@@ -75,7 +79,7 @@ struct symbol {
         char *name;
         enum symbol_type type;
         struct symbol_value curr;
-        struct symbol_value def[4];
+        struct symbol_value def[S_DEF_COUNT];
         tristate visible;
         int flags;
         struct property *prop;
@@ -84,42 +88,64 @@ struct symbol {
 
 #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_CONST            0x0001
-#define SYMBOL_CHECK            0x0008
-#define SYMBOL_CHOICE           0x0010
-#define SYMBOL_CHOICEVAL        0x0020
-#define SYMBOL_VALID            0x0080
-#define SYMBOL_OPTIONAL         0x0100
-#define SYMBOL_WRITE            0x0200
-#define SYMBOL_CHANGED          0x0400
-#define SYMBOL_AUTO             0x1000
-#define SYMBOL_CHECKED          0x2000
-#define SYMBOL_WARNED           0x8000
-#define SYMBOL_DEF              0x10000
-#define SYMBOL_DEF_USER         0x10000
-#define SYMBOL_DEF_AUTO         0x20000
-#define SYMBOL_DEF3             0x40000
-#define SYMBOL_DEF4             0x80000
+#define SYMBOL_CONST      0x0001  /* symbol is const */
+#define SYMBOL_CHECK      0x0008  /* used during dependency checking */
+#define SYMBOL_CHOICE     0x0010  /* start of a choice block (null name) */
+#define SYMBOL_CHOICEVAL  0x0020  /* used as a value in a choice block */
+#define SYMBOL_VALID      0x0080  /* set when symbol.curr is calculated */
+#define SYMBOL_OPTIONAL   0x0100  /* choice is optional - values can be 'n' */
+#define SYMBOL_WRITE      0x0200  /* ? */
+#define SYMBOL_CHANGED    0x0400  /* ? */
+#define SYMBOL_AUTO       0x1000  /* value from environment variable */
+#define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
+#define SYMBOL_WARNED     0x8000  /* warning has been issued */
+
+/* Set when symbol.def[] is used */
+#define SYMBOL_DEF        0x10000  /* First bit of SYMBOL_DEF */
+#define SYMBOL_DEF_USER   0x10000  /* symbol.def[S_DEF_USER] is valid */
+#define SYMBOL_DEF_AUTO   0x20000  /* symbol.def[S_DEF_AUTO] is valid */
+#define SYMBOL_DEF3       0x40000  /* symbol.def[S_DEF_3] is valid */
+#define SYMBOL_DEF4       0x80000  /* symbol.def[S_DEF_4] is valid */
 
 #define SYMBOL_MAXLENGTH        256
 #define SYMBOL_HASHSIZE         257
 #define SYMBOL_HASHMASK         0xff
 
+/* A property represent the config options that can be associated
+ * with a config "symbol".
+ * Sample:
+ * config FOO
+ *         default y
+ *         prompt "foo prompt"
+ *         select BAR
+ * config BAZ
+ *         int "BAZ Value"
+ *         range 1..255
+ */
 enum prop_type {
-        P_UNKNOWN, P_PROMPT, P_COMMENT, P_MENU, P_DEFAULT, P_CHOICE,
-        P_SELECT, P_RANGE, P_ENV
+        P_UNKNOWN,
+        P_PROMPT,   /* prompt "foo prompt" or "BAZ Value" */
+        P_COMMENT,  /* text associated with a comment */
+        P_MENU,     /* prompt associated with a menuconfig option */
+        P_DEFAULT,  /* default y */
+        P_CHOICE,   /* choice value */
+        P_SELECT,   /* select BAR */
+        P_RANGE,    /* range 7..100 (for a symbol) */
+        P_ENV,      /* value from environment variable */
 };
 
 struct property {
-        struct property *next;
-        struct symbol *sym;
-        enum prop_type type;
-        const char *text;
+        struct property *next;     /* next property - null if last */
+        struct symbol *sym;        /* the symbol for which the property is associated */
+        enum prop_type type;       /* type of property */
+        const char *text;          /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
         struct expr_value visible;
-        struct expr *expr;
-        struct menu *menu;
-        struct file *file;
-        int lineno;
+        struct expr *expr;         /* the optional conditional part of the property */
+        struct menu *menu;         /* the menu the property are associated with
+                                    * valid for: P_SELECT, P_RANGE, P_CHOICE,
+                                    * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
+        struct file *file;         /* what file was this property defined */
+        int lineno;                /* what lineno was this property defined */
 };
 
 #define for_all_properties(sym, st, tok) \