Which ethtool methods should I implement?

I'm adding support for ethtool to my driver 
(drivers/net/ethernet/qualcomm/emac/), and I can't find any meaningful 
HOWTO documentation, so I'm not sure which methods I need to implement.

Is there some minimal set of must-have ethtool methods that should be 
implemented?  Since I support phylib, I guess I should use 
phy_ethtool_get_link_ksettings and phy_ethtool_set_link_ksettings.  What 
else?

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Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
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