diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index d75f038..2a43a7a 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -38,8 +38,11 @@
 #define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH                  -0x4C00  /**< Signature is valid but shorter than the user-supplied length. */
 
 #if !defined(MBEDTLS_ECP_ALT)
-// Regular implementation
+// default mbed TLS elliptic curve arithmetic implementation
 //
+// (in case MBEDTLS_ECP_ALT is defined then the developer has to provide an
+// alternative implementation for the whole module and it will replace this
+// one.)
 
 #ifdef __cplusplus
 extern "C" {
@@ -666,7 +669,7 @@
  */
 int mbedtls_ecp_self_test( int verbose );
 
-#endif // MBEDTLS_SELF_TEST
+#endif /* MBEDTLS_SELF_TEST */
 
 #ifdef __cplusplus
 }