diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 2190ac5..b2a9a2e 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -2623,7 +2623,9 @@
  *
  * Module:  library/psa_crypto_storage.c
  *
- * Requires: MBEDTLS_PSA_CRYPTO_C, MBEDTLS_PSA_CRYPTO_STORAGE_FILE_C
+ * Requires: MBEDTLS_PSA_CRYPTO_C and one of either
+ * MBEDTLS_PSA_CRYPTO_STORAGE_FILE_C or MBEDTLS_PSA_CRYPTO_STORAGE_ITS_C
+ * (but not both)
  *
  */
 #define MBEDTLS_PSA_CRYPTO_STORAGE_C
@@ -2642,6 +2644,19 @@
 #define MBEDTLS_PSA_CRYPTO_STORAGE_FILE_C
 
 /**
+ * \def MBEDTLS_PSA_CRYPTO_STORAGE_ITS_C
+ *
+ * Enable persistent key storage over PSA ITS for the
+ * Platform Security Architecture cryptography API.
+ *
+ * Module:  library/psa_crypto_storage_its.c
+ *
+ * Requires: MBEDTLS_PSA_CRYPTO_C, MBEDTLS_PSA_HAS_ITS_IO
+ *
+ */
+//#define MBEDTLS_PSA_CRYPTO_STORAGE_ITS_C
+
+/**
  * \def MBEDTLS_RIPEMD160_C
  *
  * Enable the RIPEMD-160 hash algorithm.