add a feature flag for device tree support

Signed-off-by: Imre Kaloz <kaloz@openwrt.org>

SVN-Revision: 38893

Config.in

@@ -204,7 +204,7 @@ menu "Target Images"
 
 	config TARGET_ROOTFS_INCLUDE_DTB
 		bool "Include DTB in root filesystem"
-		depends on TARGET_ROOTFS_UBIFS || TARGET_ROOTFS_EXT4FS
+		depends on USES_DEVICETREE && (TARGET_ROOTFS_UBIFS || TARGET_ROOTFS_EXT4FS)
 		default n if USES_UBIFS
 		help
 		  Include the device tree blob file(s) in the rootfs. Typically the DTBs

include/target.mk

@@ -167,6 +167,9 @@ ifeq ($(DUMP),1)
     .SILENT: $(TMP_CONFIG)
     .PRECIOUS: $(TMP_CONFIG)
 
+    ifneq ($(CONFIG_OF),)
+      FEATURES += dt
+    endif
     ifneq ($(CONFIG_GENERIC_GPIO)$(CONFIG_GPIOLIB),)
       FEATURES += gpio
     endif

scripts/metadata.pl

@@ -158,6 +158,7 @@ sub target_config_features(@) {
 		/broken/ and $ret .= "\tdepends on BROKEN\n";
 		/audio/ and $ret .= "\tselect AUDIO_SUPPORT\n";
 		/display/ and $ret .= "\tselect DISPLAY_SUPPORT\n";
+		/dt/ and $ret .= "\tselect USES_DEVICETREE\n";
 		/gpio/ and $ret .= "\tselect GPIO_SUPPORT\n";
 		/pci/ and $ret .= "\tselect PCI_SUPPORT\n";
 		/pcie/ and $ret .= "\tselect PCIE_SUPPORT\n";

target/Config.in

@@ -39,6 +39,9 @@ config RTC_SUPPORT
 config BIG_ENDIAN
 	bool
 
+config USES_DEVICETREE
+	bool
+
 config USES_INITRAMFS
 	bool