diff --git a/Include/dsp/interpolation_functions.h b/Include/dsp/interpolation_functions.h
index 3c0e7fcf..6e51f7c8 100755
--- a/Include/dsp/interpolation_functions.h
+++ b/Include/dsp/interpolation_functions.h
@@ -202,7 +202,7 @@ extern "C"
    *
    */
   q31_t arm_linear_interp_q31(
-  q31_t * pYData,
+  const q31_t * pYData,
   q31_t x,
   uint32_t nValues);
 
@@ -220,7 +220,7 @@ extern "C"
    *
    */
   q15_t arm_linear_interp_q15(
-  q15_t * pYData,
+  const q15_t * pYData,
   q31_t x,
   uint32_t nValues);
 
@@ -237,7 +237,7 @@ extern "C"
    * This function can support maximum of table size 2^12.
    */
 q7_t arm_linear_interp_q7(
-  q7_t * pYData,
+  const q7_t * pYData,
   q31_t x,
   uint32_t nValues);
 
diff --git a/Source/InterpolationFunctions/arm_linear_interp_q15.c b/Source/InterpolationFunctions/arm_linear_interp_q15.c
index 70019b66..e6339f30 100755
--- a/Source/InterpolationFunctions/arm_linear_interp_q15.c
+++ b/Source/InterpolationFunctions/arm_linear_interp_q15.c
@@ -51,7 +51,7 @@
    *
    */
   q15_t arm_linear_interp_q15(
-  q15_t * pYData,
+  const q15_t * pYData,
   q31_t x,
   uint32_t nValues)
   {
diff --git a/Source/InterpolationFunctions/arm_linear_interp_q31.c b/Source/InterpolationFunctions/arm_linear_interp_q31.c
index 55348eda..f0c75604 100755
--- a/Source/InterpolationFunctions/arm_linear_interp_q31.c
+++ b/Source/InterpolationFunctions/arm_linear_interp_q31.c
@@ -52,7 +52,7 @@
    *
    */
   q31_t arm_linear_interp_q31(
-  q31_t * pYData,
+  const q31_t * pYData,
   q31_t x,
   uint32_t nValues)
   {
diff --git a/Source/InterpolationFunctions/arm_linear_interp_q7.c b/Source/InterpolationFunctions/arm_linear_interp_q7.c
index db34b01e..8d154325 100755
--- a/Source/InterpolationFunctions/arm_linear_interp_q7.c
+++ b/Source/InterpolationFunctions/arm_linear_interp_q7.c
@@ -51,7 +51,7 @@
    * This function can support maximum of table size 2^12.
    */
   q7_t arm_linear_interp_q7(
-  q7_t * pYData,
+  const q7_t * pYData,
   q31_t x,
   uint32_t nValues)
   {