Revert "Introduce PHY listing and link_topology tracking"

This reverts commit 32bb4515e34469975abc936deb0a116c4a445817.
This reverts commit d078d480639a4f3b5fc2d56247afa38e0956483a.
This reverts commit fcc4b105caa4b844bf043375bf799c20a9c99db1.
This reverts commit 345237dbc1bdbb274c9fb9ec38976261ff4a40b8.
This reverts commit 7db69ec9cfb8b4ab50420262631fb2d1908b25bf.
This reverts commit 95132a018f00f5dad38bdcfd4180d1af955d46f6.
This reverts commit 63d5eaf35ac36cad00cfb3809d794ef0078c822b.
This reverts commit c29451aefcb42359905d18678de38e52eccb3bb5.
This reverts commit 2ab0edb505faa9ac90dee1732571390f074e8113.
This reverts commit dedd702a35793ab462fce4c737eeba0badf9718e.
This reverts commit 034fcc210349b873ece7356905be5c6ca11eef2a.
This reverts commit 9c5625f559ad6fe9f6f733c11475bf470e637d34.
This reverts commit 02018c544ef113e980a2349eba89003d6f399d22.

Looks like we need more time for reviews, and incremental
changes will be hard to make sense of. So revert.

Link: https://lore.kernel.org/all/ZZP6FV5sXEf+xd58@shell.armlinux.org.uk/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: ethtool: plca: Target the command to the requested PHY

PLCA is a PHY-specific command. Instead of targeting the command
towards dev->phydev, use the request to pick the targeted PHY.

Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

ethtool: plca: fix plca enable data type while parsing the value

The ETHTOOL_A_PLCA_ENABLED data type is u8. But while parsing the
value from the attribute, nla_get_u32() is used in the plca_update_sint()
function instead of nla_get_u8(). So plca_cfg.enabled variable is updated
with some garbage value instead of 0 or 1 and always enables plca even
though plca is disabled through ethtool application. This bug has been
fixed by parsing the values based on the attributes type in the policy.

Fixes: 8580e16c28f3 ("net/ethtool: add netlink interface for the PLCA RS")
Signed-off-by: Parthiban Veerasooran <Parthiban.Veerasooran@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20230908044548.5878-1-Parthiban.Veerasooran@microchip.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ethtool: netlink: always pass genl_info to .prepare_data

We had a number of bugs in the past because developers forgot
to fully test dumps, which pass NULL as info to .prepare_data.
.prepare_data implementations would try to access info->extack
leading to a null-deref.

Now that dumps and notifications can access struct genl_info
we can pass it in, and remove the info null checks.

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com> # pause
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Link: https://lore.kernel.org/r/20230814214723.2924989-11-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

ethtool: netlink: convert commands to common SET

Convert all SET commands where new common code is applicable.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

plca.c: fix obvious mistake in checking retval

Revert a wrong fix that was done during the review process. The
intention was to substitute "if(ret < 0)" with "if(ret)".
Unfortunately, the intended fix did not meet the code.
Besides, after additional review, it was decided that "if(ret < 0)"
was actually the right thing to do.

Fixes: 8580e16c28f3 ("net/ethtool: add netlink interface for the PLCA RS")
Signed-off-by: Piergiorgio Beruto <piergiorgio.beruto@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/f2277af8951a51cfee2fb905af8d7a812b7beaf4.1673616357.git.piergiorgio.beruto@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/ethtool: add netlink interface for the PLCA RS

Add support for configuring the PLCA Reconciliation Sublayer on
multi-drop PHYs that support IEEE802.3cg-2019 Clause 148 (e.g.,
10BASE-T1S). This patch adds the appropriate netlink interface
to ethtool.

Signed-off-by: Piergiorgio Beruto <piergiorgio.beruto@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>