diff --git a/include/psa/crypto_builtin_key_derivation.h b/include/psa/crypto_builtin_key_derivation.h
index 1913a9b54..18e3fde93 100644
--- a/include/psa/crypto_builtin_key_derivation.h
+++ b/include/psa/crypto_builtin_key_derivation.h
@@ -105,5 +105,14 @@ typedef struct psa_tls12_prf_key_derivation_s {
 } psa_tls12_prf_key_derivation_t;
 #endif /* MBEDTLS_PSA_BUILTIN_ALG_TLS12_PRF) ||
         * MBEDTLS_PSA_BUILTIN_ALG_TLS12_PSK_TO_MS */
+#if defined(MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC)
+typedef enum {
+    PSA_PBKDF2_STATE_INIT,             /* no input provided */
+    PSA_PBKDF2_STATE_INPUT_COST_SET,   /* input cost has been set */
+    PSA_PBKDF2_STATE_SALT_SET,         /* salt has been set */
+    PSA_PBKDF2_STATE_PASSWORD_SET,     /* password has been set */
+    PSA_PBKDF2_STATE_OUTPUT            /* output has been started */
+} psa_pbkdf2_key_derivation_state_t;
 
+#endif /* MBEDTLS_PSA_BUILTIN_ALG_PBKDF2_HMAC */
 #endif /* PSA_CRYPTO_BUILTIN_KEY_DERIVATION_H */