The driver and firmware sync up through SYNC messages, and the firmware's affirmative reply to these SYNC messages appears to be the "Reset" indication received via the status interrupt endpoint. Thus the driver needs the status interrupt endpoint always active so that the Reset indication can be received even if the netdev is closed, which is the case right after device insertion. Signed-off-by: Dan Williams <dcbw@xxxxxxxxxx> --- diff --git a/drivers/net/usb/sierra_net.c b/drivers/net/usb/sierra_net.c index 18dd425..e6e2857 100644 --- a/drivers/net/usb/sierra_net.c +++ b/drivers/net/usb/sierra_net.c @@ -905,7 +905,7 @@ static struct sk_buff *sierra_net_tx_fixup(struct usbnet *dev, static const struct driver_info sierra_net_info_direct_ip = { .description = "Sierra Wireless USB-to-WWAN Modem", - .flags = FLAG_WWAN | FLAG_SEND_ZLP, + .flags = FLAG_WWAN | FLAG_SEND_ZLP | FLAG_INTR_ALWAYS, .bind = sierra_net_bind, .unbind = sierra_net_unbind, .status = sierra_net_status, -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html