diff --git a/include/psa/crypto_values.h b/include/psa/crypto_values.h
index 4df4fe4350..45c16b0a05 100644
--- a/include/psa/crypto_values.h
+++ b/include/psa/crypto_values.h
@@ -57,6 +57,13 @@
  * value, check with the Arm PSA framework group to pick one that other
  * domains aren't already using. */
 
+/* Tell uncrustify not to touch the constant definitions, otherwise
+ * it might change the spacing to something that is not PSA-compliant
+ * (e.g. adding a space after casts).
+ *
+ * *INDENT-OFF*
+ */
+
 /** The action was completed successfully. */
 #define PSA_SUCCESS ((psa_status_t)0)
 
@@ -327,6 +334,8 @@
  */
 #define PSA_ERROR_DATA_INVALID          ((psa_status_t)-153)
 
+/* *INDENT-ON* */
+
 /**@}*/
 
 /** \defgroup crypto_types Key and algorithm types