net: lan78xx: Support auto-downshift to 100Mb/s
authorPhil Elwell <phil@raspberrypi.org>
Mon, 26 Nov 2018 19:46:58 +0000 (19:46 +0000)
committerpopcornmix <popcornmix@gmail.com>
Wed, 1 Jul 2020 15:32:46 +0000 (16:32 +0100)
commit1bd354134205266f0af4c674e1df298d7f33413e
tree4e5a6992563436aab323e41b21b39bb7ec257aaf
parent64f44d8645d1187d258744c95cd6f5b4a203beeb
net: lan78xx: Support auto-downshift to 100Mb/s

Ethernet cables with faulty or missing pairs (specifically pairs C and
D) allow auto-negotiation to 1000Mbs, but do not support the successful
establishment of a link. Add a DT property, "microchip,downshift-after",
to configure the number of auto-negotiation failures after which it
falls back to 100Mbs. Valid values are 2, 3, 4, 5 and 0, where 0 means
never downshift.

Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Documentation/devicetree/bindings/net/microchip,lan78xx.txt
drivers/net/phy/microchip.c
include/linux/microchipphy.h