1 files changed, 4 insertions, 0 deletions
diff --git a/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
index c739775d23..d92c432530 100644
--- a/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
+++ b/OvmfPkg/Tcg/Tcg2Config/Tpm12Support.h
@@ -15,6 +15,10 @@
 /**
   Detect the presence of a TPM with interface version 1.2.
 
+  @retval EFI_UNSUPPORTED  The platform that includes this particular
+                           implementation of the function does not support
+                           TPM-1.2.
+
   @retval EFI_SUCCESS      TPM-1.2 available. The Tpm12RequestUseTpm() and
                            Tpm12SubmitCommand(TPM_ORD_GetTicks) operations
                            (from the Tpm12DeviceLib class) have succeeded.