.bLength                = USB_DT_ENDPOINT_SIZE,
        .bDescriptorType        = USB_DT_ENDPOINT,
        .bEndpointAddress       = USB_DIR_IN,
-       .bmAttributes           = USB_ENDPOINT_XFER_ISOC,
+       .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
+                               | USB_ENDPOINT_XFER_ISOC,
        /* The wMaxPacketSize and bInterval values will be initialized from
         * module parameters.
         */
        .bLength                = USB_DT_ENDPOINT_SIZE,
        .bDescriptorType        = USB_DT_ENDPOINT,
        .bEndpointAddress       = USB_DIR_IN,
-       .bmAttributes           = USB_ENDPOINT_XFER_ISOC,
+       .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
+                               | USB_ENDPOINT_XFER_ISOC,
        /* The wMaxPacketSize and bInterval values will be initialized from
         * module parameters.
         */
        .bDescriptorType        = USB_DT_ENDPOINT,
 
        .bEndpointAddress       = USB_DIR_IN,
-       .bmAttributes           = USB_ENDPOINT_XFER_ISOC,
+       .bmAttributes           = USB_ENDPOINT_SYNC_ASYNC
+                               | USB_ENDPOINT_XFER_ISOC,
        /* The wMaxPacketSize and bInterval values will be initialized from
         * module parameters.
         */