Kristian Evensen [off-list ref] writes:
+void usbnet_cdc_zte_status(struct usbnet *dev, struct urb *urb)
+{
+ struct usb_cdc_notification *event;
+
+ if (urb->actual_length < sizeof(*event))
+ return;
+
+ event = urb->transfer_buffer;
+
+ if (event->bNotificationType != USB_CDC_NOTIFY_NETWORK_CONNECTION) {
+ usbnet_cdc_status(dev, urb);
+ return;
+ }
+
+ netif_dbg(dev, timer, dev->net, "CDC: carrier %s\n",
+ event->wValue ? "on" : "off");
+
+ if (event->wValue &&
+ !test_bit(__LINK_STATE_NOCARRIER, &dev->net->state))
+ usbnet_link_change(dev, 0, 0);
+
+ usbnet_link_change(dev, !!event->wValue, 0);
+}
As Henning said: Use netif_carrier_ok instead of open coding it.
But I also think you need to replace the first usbnet_link_change() with
a plain netif_carrier_off(dev->net). Calling usbnet_link_change() twice
here is only going to set off the "kevent XX may have been dropped"
message since you call schedule_work() twice without giving the work
queue a chance to be processed. No need to do that.
Bjørn