diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 465ca06..4b36c4c 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -668,7 +668,7 @@
         return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
     }
 
-    status = psa_generator_read( &generator, dstbuf, dlen );
+    status = psa_key_derivation_output_bytes( &generator, dstbuf, dlen );
     if( status != PSA_SUCCESS )
     {
         psa_generator_abort( &generator );
@@ -1135,8 +1135,9 @@
                 return( MBEDTLS_ERR_SSL_HW_ACCEL_FAILED );
             }
 
-            status = psa_generator_read( &generator, session->master,
-                                         master_secret_len );
+            status = psa_key_derivation_output_bytes( &generator,
+                                                      session->master,
+                                                      master_secret_len );
             if( status != PSA_SUCCESS )
             {
                 psa_generator_abort( &generator );