diff --git a/usr/Kconfig b/usr/Kconfig
index c0c4850..ad0543e 100644
--- a/usr/Kconfig
+++ b/usr/Kconfig
@@ -220,6 +220,7 @@
 endchoice
 
 config INITRAMFS_COMPRESSION
+	depends on INITRAMFS_SOURCE!=""
 	string
 	default ""      if INITRAMFS_COMPRESSION_NONE
 	default ".gz"   if INITRAMFS_COMPRESSION_GZIP