net: dsa: microchip: correct KSZ8795 static MAC table access

net: dsa: microchip: correct KSZ8795 static MAC table access

commit 4bdf79d686b49ac49373b36466acfb93972c7d7c upstream.

The KSZ8795 driver code was modified to use on KSZ8863/73, which has
different register definitions.  Some of the new KSZ8795 register
information are wrong compared to previous code.

KSZ8795 also behaves differently in that the STATIC_MAC_TABLE_USE_FID
and STATIC_MAC_TABLE_FID bits are off by 1 when doing MAC table reading
than writing.  To compensate that a special code was added to shift the
register value by 1 before applying those bits.  This is wrong when the
code is running on KSZ8863, so this special code is only executed when
KSZ8795 is detected.

Fixes: 4b20a07e103f ("net: dsa: microchip: ksz8795: add support for ksz88xx chips")
Signed-off-by: Tristram Ha <Tristram.Ha@microchip.com>
Reviewed-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jörg Sommer <joerg@jo-so.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>