diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index a6c4a1b..94a14f5 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1680,7 +1680,7 @@
 	if (--acm->susp_count)
 		goto out;
 
-	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags)) {
+	if (tty_port_initialized(&acm->port)) {
 		rv = usb_submit_urb(acm->ctrlurb, GFP_ATOMIC);
 
 		for (;;) {
@@ -1710,7 +1710,7 @@
 {
 	struct acm *acm = usb_get_intfdata(intf);
 
-	if (test_bit(ASYNCB_INITIALIZED, &acm->port.flags))
+	if (tty_port_initialized(&acm->port))
 		tty_port_tty_hangup(&acm->port, false);
 
 	return acm_resume(intf);