Under what conditions is phy_device "adjust_link()" called?

[rpjday]

I can see from the documentation that the callback adjust_link() is invoked
"for the enet controller to respond to changes in the link state." Is there
a specific list of the events that would generate such a change? Are we
talking initially opening the device, ifup/ifdown, physically unplugging
from the port, some or all of the above?

Not a network expert (yet), so I'm still digging through the code. Thanks.

rday