Introduce cable testing support for the DP83TG720 PHY. This implementation
is based on the "DP83TG720S-Q1: Configuring for Open Alliance Specification
Compliance (Rev. B)" application note.
The feature has been tested with cables of various lengths:
- No cable: 1m till open reported.
- 5 meter cable: reported properly.
- 20 meter cable: reported as 19m.
- 40 meter cable: reported as cable ok.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://patch.msgid.link/20240812073046.1728288-3-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Get master/slave configuration for initial system start with the link in
down state. This ensures ethtool shows current configuration. Also
fixes link reconfiguration with ethtool while in down state, preventing
ethtool from displaying outdated configuration.
Even though dp83tg720_config_init() is executed periodically as long as
the link is in admin up state but no carrier is detected, this is not
sufficient for the link in admin down state where
dp83tg720_read_status() is not periodically executed. To cover this
case, we need an extra read role configuration in
dp83tg720_config_aneg().
Fixes: cb80ee2f9b ("net: phy: Add support for the DP83TG720S Ethernet PHY")
Cc: stable@vger.kernel.org
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20240614094516.1481231-2-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
