diff --git a/hw/tpm/tpm_emulator.c b/hw/tpm/tpm_emulator.c
index 47f37d6cacd48d03ebb72177d1d4a603835bd192..94e6660a5a8a06a31f8e0913d193667c6dc573b3 100644
--- a/hw/tpm/tpm_emulator.c
+++ b/hw/tpm/tpm_emulator.c
@@ -463,22 +463,16 @@ err:
     return -1;
 }
 
-static TPMBackend *tpm_emulator_create(QemuOpts *opts, const char *id)
+static TPMBackend *tpm_emulator_create(QemuOpts *opts)
 {
     TPMBackend *tb = TPM_BACKEND(object_new(TYPE_TPM_EMULATOR));
 
-    tb->id = g_strdup(id);
-
     if (tpm_emulator_handle_device_opts(TPM_EMULATOR(tb), opts)) {
-        goto err_exit;
+        object_unref(OBJECT(tb));
+        return NULL;
     }
 
     return tb;
-
-err_exit:
-    object_unref(OBJECT(tb));
-
-    return NULL;
 }
 
 static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
diff --git a/hw/tpm/tpm_passthrough.c b/hw/tpm/tpm_passthrough.c
index 9326cbfdc9147ba47e597849d7c1ade0f25b9f90..7371d507396406814c88d53771c1adaa61b71315 100644
--- a/hw/tpm/tpm_passthrough.c
+++ b/hw/tpm/tpm_passthrough.c
@@ -284,13 +284,10 @@ tpm_passthrough_handle_device_opts(TPMPassthruState *tpm_pt, QemuOpts *opts)
     return 1;
 }
 
-static TPMBackend *tpm_passthrough_create(QemuOpts *opts, const char *id)
+static TPMBackend *tpm_passthrough_create(QemuOpts *opts)
 {
     Object *obj = object_new(TYPE_TPM_PASSTHROUGH);
-    TPMBackend *tb = TPM_BACKEND(obj);
-    TPMPassthruState *tpm_pt = TPM_PASSTHROUGH(tb);
-
-    tb->id = g_strdup(id);
+    TPMPassthruState *tpm_pt = TPM_PASSTHROUGH(obj);
 
     if (tpm_passthrough_handle_device_opts(tpm_pt, opts)) {
         goto err_exit;
@@ -301,7 +298,7 @@ static TPMBackend *tpm_passthrough_create(QemuOpts *opts, const char *id)
         goto err_exit;
     }
 
-    return tb;
+    return TPM_BACKEND(obj);
 
 err_exit:
     object_unref(obj);
diff --git a/include/sysemu/tpm_backend.h b/include/sysemu/tpm_backend.h
index ce8dee58cfb4922b45b8ad5ed6c1721a9bb59994..1ad27ec3745c408c5a0d9498ac0c93c7dae2cc4b 100644
--- a/include/sysemu/tpm_backend.h
+++ b/include/sysemu/tpm_backend.h
@@ -63,7 +63,7 @@ struct TPMBackendClass {
     /* get a descriptive text of the backend to display to the user */
     const char *desc;
 
-    TPMBackend *(*create)(QemuOpts *opts, const char *id);
+    TPMBackend *(*create)(QemuOpts *opts);
 
     /* start up the TPM on the backend - optional */
     int (*startup_tpm)(TPMBackend *t);
diff --git a/tpm.c b/tpm.c
index 32d398aadf5e76de71f26a46ef351cdc82f3d6a3..520f4492349d97268584f4e049303cc19496c75b 100644
--- a/tpm.c
+++ b/tpm.c
@@ -127,11 +127,12 @@ static int tpm_init_tpmdev(void *dummy, QemuOpts *opts, Error **errp)
         return 1;
     }
 
-    drv = be->create(opts, id);
+    drv = be->create(opts);
     if (!drv) {
         return 1;
     }
 
+    drv->id = g_strdup(id);
     QLIST_INSERT_HEAD(&tpm_backends, drv, list);
 
     return 0;