kconfig: add alldefconfig

alldefconfig create a configuration with all values set
to their default value (form the Kconfig files).

This may be useful when we try to use more sensible default
values and may also be used in combination with
the minimal defconfigs.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Michal Marek <mmarek@suse.cz>
diff --git a/Documentation/kbuild/kconfig.txt b/Documentation/kbuild/kconfig.txt
index 49efae7..0e69dd5 100644
--- a/Documentation/kbuild/kconfig.txt
+++ b/Documentation/kbuild/kconfig.txt
@@ -65,7 +65,7 @@
 filename that contains config symbols that the user requires to be
 set to a specific value.  If KCONFIG_ALLCONFIG is used without a
 filename, "make *config" checks for a file named
-"all{yes/mod/no/random}.config" (corresponding to the *config command
+"all{yes/mod/no/def/random}.config" (corresponding to the *config command
 that was used) for symbol values that are to be forced.  If this file
 is not found, it checks for a file named "all.config" to contain forced
 values.
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index 01bad1b..7297359 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -85,9 +85,9 @@
 	$(Q)rm -f arch/um/Kconfig.arch
 	$(Q)rm -f $(obj)/config.pot
 
-PHONY += allnoconfig allyesconfig allmodconfig randconfig
+PHONY += allnoconfig allyesconfig allmodconfig alldefconfig randconfig
 
-allnoconfig allyesconfig allmodconfig randconfig: $(obj)/conf
+allnoconfig allyesconfig allmodconfig alldefconfig randconfig: $(obj)/conf
 	$< --$@ $(Kconfig)
 
 PHONY += listnewconfig oldnoconfig defconfig
@@ -117,11 +117,12 @@
 	@echo  '  localmodconfig  - Update current config disabling modules not loaded'
 	@echo  '  localyesconfig  - Update current config converting local mods to core'
 	@echo  '  silentoldconfig - Same as oldconfig, but quietly, additionally update deps'
-	@echo  '  randconfig	  - New config with random answer to all options'
-	@echo  '  defconfig	  - New config with default answer to all options'
-	@echo  '  allmodconfig	  - New config selecting modules when possible'
-	@echo  '  allyesconfig	  - New config where all options are accepted with yes'
+	@echo  '  defconfig	  - New config with default from ARCH supplied defconfig'
 	@echo  '  allnoconfig	  - New config where all options are answered with no'
+	@echo  '  allyesconfig	  - New config where all options are accepted with yes'
+	@echo  '  allmodconfig	  - New config selecting modules when possible'
+	@echo  '  alldefconfig    - New config with all symbols set to default'
+	@echo  '  randconfig	  - New config with random answer to all options'
 	@echo  '  listnewconfig   - List new options'
 	@echo  '  oldnoconfig     - Same as silentoldconfig but set new symbols to n (unset)'
 
diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index ff5c914..c8bd33c 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -27,6 +27,7 @@
 	allnoconfig,
 	allyesconfig,
 	allmodconfig,
+	alldefconfig,
 	randconfig,
 	defconfig,
 	listnewconfig,
@@ -446,6 +447,7 @@
 	{"allnoconfig",     no_argument,       NULL, allnoconfig},
 	{"allyesconfig",    no_argument,       NULL, allyesconfig},
 	{"allmodconfig",    no_argument,       NULL, allmodconfig},
+	{"alldefconfig",    no_argument,       NULL, alldefconfig},
 	{"randconfig",      no_argument,       NULL, randconfig},
 	{"listnewconfig",   no_argument,       NULL, listnewconfig},
 	{"oldnoconfig",     no_argument,       NULL, oldnoconfig},
@@ -534,6 +536,7 @@
 	case allnoconfig:
 	case allyesconfig:
 	case allmodconfig:
+	case alldefconfig:
 	case randconfig:
 		name = getenv("KCONFIG_ALLCONFIG");
 		if (name && !stat(name, &tmpstat)) {
@@ -544,6 +547,7 @@
 		case allnoconfig:	name = "allno.config"; break;
 		case allyesconfig:	name = "allyes.config"; break;
 		case allmodconfig:	name = "allmod.config"; break;
+		case alldefconfig:	name = "alldef.config"; break;
 		case randconfig:	name = "allrandom.config"; break;
 		default: break;
 		}
@@ -578,6 +582,9 @@
 	case allmodconfig:
 		conf_set_all_new_symbols(def_mod);
 		break;
+	case alldefconfig:
+		conf_set_all_new_symbols(def_default);
+		break;
 	case randconfig:
 		conf_set_all_new_symbols(def_random);
 		break;