diff --git a/include/psa/crypto_extra.h b/include/psa/crypto_extra.h
index f0e4782..99bb063 100644
--- a/include/psa/crypto_extra.h
+++ b/include/psa/crypto_extra.h
@@ -186,6 +186,9 @@
  * \retval #PSA_ERROR_ALREADY_EXISTS
  *         There is already a key with the identifier specified in
  *         \p attributes.
+ * \retval #PSA_ERROR_NOT_SUPPORTED
+ *         The secure element driver for the specified lifetime does not
+ *         support registering a key.
  * \retval #PSA_ERROR_INVALID_ARGUMENT
  *         \p attributes specifies a lifetime which is not located
  *         in a secure element.