diff --git a/package/tpm2-tss/Config.in b/package/tpm2-tss/Config.in
index 91337ce48d..f4bd8c3cdb 100644
--- a/package/tpm2-tss/Config.in
+++ b/package/tpm2-tss/Config.in
@@ -56,6 +56,7 @@ config BR2_PACKAGE_TPM2_TSS_FAPI
 	  https://trustedcomputinggroup.org/wp-content/uploads/TSS_JSON_Policy_v0.7_r04_pubrev.pdf
 
 comment "FAPI not supported with Mbed TLS backend"
+	depends on BR2_TOOLCHAIN_HAS_SYNC_4
 	depends on BR2_PACKAGE_MBEDTLS
 
 endif