diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst index a1c711af..af072efe 100644 --- a/CONTRIBUTING.rst +++ b/CONTRIBUTING.rst @@ -493,3 +493,17 @@ within interrupt context is not allowed, so the Board Support Package (BSP) should support the `Interrupt Manager `_ in general. + +Network Interface Drivers Hints +=============================== + +Link Up/Down Events +------------------- + +You can notifiy the application space of link up/down events in your network +interface driver via the +``if_link_state_change(LINK_STATE_UP/LINK_STATE_DOWN)`` function. The +DHCPCD(8) client is a consumer of these events for example. Make sure that the +interface flag ``IFF_UP`` and the interface driver flag ``IFF_DRV_RUNNING`` is +set in case the link is up, otherwise ``ether_output()`` will return the error +status ``ENETDOWN``.