dp83640: Verify calibration pin assignment

This constraints the pin assignment to not allow the calibration function to
be reassigned and only allow reassigning the calibratin pin if only one phy is
connected.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed