diff --git a/wolfcrypt/src/sha256.c b/wolfcrypt/src/sha256.c
index 4f498b452..e43b14859 100644
--- a/wolfcrypt/src/sha256.c
+++ b/wolfcrypt/src/sha256.c
@@ -356,14 +356,14 @@ static int InitSha256(wc_Sha256* sha256)
         return ret;
     }
 
-    static int Transform_Sha256(wc_Sha256* sha256, byte* buf)
+    static int Transform_Sha256(wc_Sha256* sha256)
     {
         int ret = wolfSSL_CryptHwMutexLock();
         if (ret == 0) {
     #ifdef FREESCALE_MMCAU_CLASSIC_SHA
-            cau_sha256_hash_n(buf, 1, sha256->digest);
+            cau_sha256_hash_n(sha256->buffer, 1, sha256->digest);
     #else
-            MMCAU_SHA256_HashN(buf, 1, sha256->digest);
+            MMCAU_SHA256_HashN(sha256->buffer, 1, sha256->digest);
     #endif
             wolfSSL_CryptHwMutexUnLock();
         }