kconfig: add an option to determine a menu's visibility

This option is aimed to add the possibility to control a menu's visibility
without adding dependency to the expression to all the submenu.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

5 files changed, 32 insertions, 3 deletions

diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index 184eb6a0b505..e57826ced380 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -164,6 +164,7 @@ struct menu {
         struct menu *list;
         struct symbol *sym;
         struct property *prompt;
+        struct expr *visibility;
         struct expr *dep;
         unsigned int flags;
         char *help;
diff --git a/scripts/kconfig/lkc.h b/scripts/kconfig/lkc.h
index 753cdbd7b805..3f7240df0f3b 100644
--- a/scripts/kconfig/lkc.h
+++ b/scripts/kconfig/lkc.h
@@ -107,6 +107,7 @@ void menu_end_menu(void);
 void menu_add_entry(struct symbol *sym);
 void menu_end_entry(void);
 void menu_add_dep(struct expr *dep);
+void menu_add_visibility(struct expr *dep);
 struct property *menu_add_prop(enum prop_type type, char *prompt, struct expr *expr, struct expr *dep);
 struct property *menu_add_prompt(enum prop_type type, char *prompt, struct expr *dep);
 void menu_add_expr(enum prop_type type, struct expr *expr, struct expr *dep);
diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c
index 7e83aef42c6d..b9d9aa18e6d6 100644
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -152,6 +152,12 @@ struct property *menu_add_prompt(enum prop_type type, char *prompt, struct expr
         return menu_add_prop(type, prompt, NULL, dep);
 }
 
+void menu_add_visibility(struct expr *expr)
+{
+        current_entry->visibility = expr_alloc_and(current_entry->visibility,
+            expr);
+}
+
 void menu_add_expr(enum prop_type type, struct expr *expr, struct expr *dep)
 {
         menu_add_prop(type, NULL, expr, dep);
@@ -410,6 +416,11 @@ bool menu_is_visible(struct menu *menu)
         if (!menu->prompt)
                 return false;
 
+        if (menu->visibility) {
+                if (expr_calc_value(menu->visibility) == no)
+                        return no;
+        }
+
         sym = menu->sym;
         if (sym) {
                 sym_calc_value(sym);
diff --git a/scripts/kconfig/zconf.gperf b/scripts/kconfig/zconf.gperf
index d8bc74249622..c9e690eb7545 100644
--- a/scripts/kconfig/zconf.gperf
+++ b/scripts/kconfig/zconf.gperf
@@ -38,6 +38,7 @@ hex,		T_TYPE,		TF_COMMAND, S_HEX
 string,         T_TYPE,         TF_COMMAND, S_STRING
 select,         T_SELECT,       TF_COMMAND
 range,          T_RANGE,        TF_COMMAND
+visible,        T_VISIBLE,      TF_COMMAND
 option,         T_OPTION,       TF_COMMAND
 on,             T_ON,           TF_PARAM
 modules,        T_OPT_MODULES,  TF_OPTION
diff --git a/scripts/kconfig/zconf.y b/scripts/kconfig/zconf.y
index 2abd3c7ff15d..49fb4ab664c3 100644
--- a/scripts/kconfig/zconf.y
+++ b/scripts/kconfig/zconf.y
@@ -36,7 +36,7 @@ static struct menu *current_menu, *current_entry;
 #define YYERROR_VERBOSE
 #endif
 %}
-%expect 28
+%expect 30
 
 %union
 {
@@ -68,6 +68,7 @@ static struct menu *current_menu, *current_entry;
 %token <id>T_DEFAULT
 %token <id>T_SELECT
 %token <id>T_RANGE
+%token <id>T_VISIBLE
 %token <id>T_OPTION
 %token <id>T_ON
 %token <string> T_WORD
@@ -123,7 +124,7 @@ stmt_list:
 ;
 
 option_name:
-        T_DEPENDS | T_PROMPT | T_TYPE | T_SELECT | T_OPTIONAL | T_RANGE | T_DEFAULT
+        T_DEPENDS | T_PROMPT | T_TYPE | T_SELECT | T_OPTIONAL | T_RANGE | T_DEFAULT | T_VISIBLE
 ;
 
 common_stmt:
@@ -359,7 +360,7 @@ menu: T_MENU prompt T_EOL
         printd(DEBUG_PARSE, "%s:%d:menu\n", zconf_curname(), zconf_lineno());
 };
 
-menu_entry: menu depends_list
+menu_entry: menu visibility_list depends_list
 {
         $$ = menu_add_menu();
 };
@@ -430,6 +431,19 @@ depends: T_DEPENDS T_ON expr T_EOL
         printd(DEBUG_PARSE, "%s:%d:depends on\n", zconf_curname(), zconf_lineno());
 };
 
+/* visibility option */
+
+visibility_list:
+          /* empty */
+        | visibility_list visible
+        | visibility_list T_EOL
+;
+
+visible: T_VISIBLE if_expr
+{
+        menu_add_visibility($2);
+};
+
 /* prompt statement */
 
 prompt_stmt_opt:
@@ -526,6 +540,7 @@ static const char *zconf_tokenname(int token)
         case T_IF:              return "if";
         case T_ENDIF:           return "endif";
         case T_DEPENDS:         return "depends";
+        case T_VISIBLE:         return "visible";
         }
         return "<token>";
 }