diff --git a/include/psa/crypto.h b/include/psa/crypto.h
index f721b7dbd..71b1de231 100644
--- a/include/psa/crypto.h
+++ b/include/psa/crypto.h
@@ -503,6 +503,8 @@ psa_status_t psa_close_key(psa_key_handle_t handle);
  * \retval #PSA_ERROR_HARDWARE_FAILURE
  * \retval #PSA_ERROR_CORRUPTION_DETECTED
  * \retval #PSA_ERROR_BAD_STATE
+ *         \p operation is either not initialized or is in use
+ * \retval #PSA_ERROR_BAD_STATE
  *         The library has not been previously initialized by psa_crypto_init().
  *         It is implementation-dependent whether a failure to initialize
  *         results in this error code.