Index: uspace/drv/bus/usb/ohci/hc.c
===================================================================
--- uspace/drv/bus/usb/ohci/hc.c	(revision ee0ffa6a7b35829ac2a78b95c14a3c35997dede4)
+++ uspace/drv/bus/usb/ohci/hc.c	(revision 705f83ae686e8cd769aac792fa6b14f88a63b757)
@@ -301,8 +301,5 @@
 	ohci_endpoint_t * const ohci_ep = ohci_endpoint_get(ep);
 	ohci_transfer_batch_t *ohci_batch = ohci_transfer_batch_get(batch);
-
 	int err;
-	if ((err = ohci_transfer_batch_prepare(ohci_batch)))
-		return err;
 
 	fibril_mutex_lock(&hc->guard);
@@ -311,4 +308,7 @@
 		return err;
 	}
+
+	if ((err = ohci_transfer_batch_prepare(ohci_batch)))
+		return err;
 
 	ohci_transfer_batch_commit(ohci_batch);