diff --git a/pkg/cmsis-dsp/Makefile b/pkg/cmsis-dsp/Makefile
index 24b67fbcc5..076da797fa 100644
--- a/pkg/cmsis-dsp/Makefile
+++ b/pkg/cmsis-dsp/Makefile
@@ -5,20 +5,29 @@ PKG_LICENSE=Apache-2.0
 
 include $(RIOTBASE)/pkg/pkg.mk
 
-# include makefiles utils tools
-include $(RIOTMAKE)/utils/strings.mk
-
 CMSIS_DSP_MODULES =                \
-    cmsis-dsp_BasicMathFunctions   \
-    cmsis-dsp_CommonTables         \
-    cmsis-dsp_ComplexMathFunctions \
-    cmsis-dsp_ControllerFunctions  \
-    cmsis-dsp_FastMathFunctions    \
-    cmsis-dsp_FilteringFunctions   \
-    cmsis-dsp_MatrixFunctions      \
-    cmsis-dsp_StatisticsFunctions  \
-    cmsis-dsp_SupportFunctions     \
-    cmsis-dsp_TransformFunctions   \
+    cmsis-dsp_basicmathfunctions   \
+    cmsis-dsp_commontables         \
+    cmsis-dsp_complexmathfunctions \
+    cmsis-dsp_controllerfunctions  \
+    cmsis-dsp_fastmathfunctions    \
+    cmsis-dsp_filteringfunctions   \
+    cmsis-dsp_matrixfunctions      \
+    cmsis-dsp_statisticsfunctions  \
+    cmsis-dsp_supportfunctions     \
+    cmsis-dsp_transformfunctions   \
+    #
+
+DIR_basicmathfunctions      := BasicMathFunctions
+DIR_commontables            := CommonTables
+DIR_complexmathfunctions    := ComplexMathFunctions
+DIR_controllerfunctions     := ControllerFunctions
+DIR_fastmathfunctions       := FastMathFunctions
+DIR_filteringfunctions      := FilteringFunctions
+DIR_matrixfunctions         := MatrixFunctions
+DIR_statisticsfunctions     := StatisticsFunctions
+DIR_supportfunctions        := SupportFunctions
+DIR_transformfunctions      := TransformFunctions
 
 .PHONY: cmsis-dsp_%
 
@@ -27,4 +36,4 @@ CFLAGS += -Wno-cast-align
 all: $(CMSIS_DSP_MODULES)
 
 cmsis-dsp_%:
-	$(MAKE) -C $(PKG_SOURCE_DIR)/CMSIS/DSP/Source/$* -f $(CURDIR)/Makefile.cmsis-dsp MODULE=$(call lowercase,$@)
+	$(MAKE) -C $(PKG_SOURCE_DIR)/CMSIS/DSP/Source/$(DIR_$*) -f $(CURDIR)/Makefile.cmsis-dsp MODULE=$@