netdev: Document use for get_etheraddr member of struct netdev_class.

This has confused developers adding hardware support, e.g.:
http://openvswitch.org/pipermail/dev/2012-April/016350.html

Signed-off-by: Ben Pfaff <blp@nicira.com>

diff --git a/lib/netdev-provider.h b/lib/netdev-provider.h
index daf46ad..6daae5e 100644 (file)
--- a/lib/netdev-provider.h
+++ b/lib/netdev-provider.h
@@ -231,7 +231,10 @@ struct netdev_class {
     /* Sets 'netdev''s Ethernet address to 'mac' */
     int (*set_etheraddr)(struct netdev *netdev, const uint8_t mac[6]);
 
-    /* Retrieves 'netdev''s Ethernet address into 'mac'. */
+    /* Retrieves 'netdev''s Ethernet address into 'mac'.
+     *
+     * This address will be advertised as 'netdev''s MAC address through the
+     * OpenFlow protocol, among other uses. */
     int (*get_etheraddr)(const struct netdev *netdev, uint8_t mac[6]);
 
     /* Retrieves 'netdev''s MTU into '*mtup'.