diff --git a/drivers/input/touchscreen/st/fts_lib/ftsIO.c b/drivers/input/touchscreen/st/fts_lib/ftsIO.c
index 12f02d9424ff..07baad393df8 100644
--- a/drivers/input/touchscreen/st/fts_lib/ftsIO.c
+++ b/drivers/input/touchscreen/st/fts_lib/ftsIO.c
@@ -84,7 +84,7 @@ int openChannel(struct i2c_client *clt)
 	return OK;
 }
 
-struct device *getDev()
+struct device *getDev(void)
 {
 	if (client != NULL)
 		return &(client->dev);
@@ -92,7 +92,7 @@ struct device *getDev()
 		return NULL;
 }
 
-struct i2c_client *getClient()
+struct i2c_client *getClient(void)
 {
 	if (client != NULL)
 		return client;
diff --git a/drivers/input/touchscreen/st/fts_lib/ftsTime.c b/drivers/input/touchscreen/st/fts_lib/ftsTime.c
index 07d1bf5dba8b..6d21fc857057 100644
--- a/drivers/input/touchscreen/st/fts_lib/ftsTime.c
+++ b/drivers/input/touchscreen/st/fts_lib/ftsTime.c
@@ -92,7 +92,7 @@ int elapsedNanosecond(struct StopWatch *w)
 	return result;
 }
 
-char *timestamp()
+char *timestamp(void)
 {
 	char *result = NULL;