diff --git a/sys/conf/files b/sys/conf/files
index 9c71811822ce..7279a6b41c97 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -1312,8 +1312,8 @@ dev/ath/ath_rate/sample/sample.c	optional ath_rate_sample \
 dev/ath/ath_dfs/null/dfs_null.c	optional ath \
 	compile-with "${NORMAL_C} -I$S/dev/ath"
 #
-dev/backlight/backlight_if.m		optional backlight
-dev/backlight/backlight.c		optional backlight
+dev/backlight/backlight_if.m		optional backlight | compat_linuxkpi
+dev/backlight/backlight.c		optional backlight | compat_linuxkpi
 dev/bce/if_bce.c			optional bce
 dev/bfe/if_bfe.c			optional bfe
 dev/bge/if_bge.c			optional bge