[PATCHv4 0/4] usbnet: speed reporting for devices without MDIO

[Grant Grundler]

This series introduces support for USB network devices that report
speed as a part of their protocol, not emulating an MII to be accessed
over MDIO.

v2: rebased on recent upstream changes
v3: incorporated hints on naming and comments
v4: fix misplaced hunks; reword some commit messages;
    add same change for cdc_ether

I'm reposting Oliver Neukum's <oneukum@xxxxxxxx> patch series with
fix ups for "misplaced hunks" (landed in the wrong patches).
Please fixup the "author" if "git am" fails to attribute the
patches 1-3 (of 4) to Oliver.

I've tested v4 series with "5.12-rc3+" kernel on Intel NUC6i5SYB
and + Sabrent NT-S25G. Google Pixelbook Go (chromeos-4.4 kernel)
+ Alpha Network AUE2500C were connected directly to the NT-S25G
to get 2.5Gbps link rate:
# ethtool enx002427880815
Settings for enx002427880815:
        Supported ports: [  ]
        Supported link modes:   Not reported
        Supported pause frame use: No
        Supports auto-negotiation: No
        Supported FEC modes: Not reported
        Advertised link modes:  Not reported
        Advertised pause frame use: No
        Advertised auto-negotiation: No
        Advertised FEC modes: Not reported
        Speed: 2500Mb/s
        Duplex: Half
        Auto-negotiation: off
        Port: Twisted Pair
        PHYAD: 0
        Transceiver: internal
        MDI-X: Unknown
        Current message level: 0x00000007 (7)
                               drv probe link
        Link detected: yes


"Duplex" is a lie since we get no information about it.

I expect "Auto-Negotiation" is always true for cdc_ncm and
cdc_ether devices and perhaps someone knows offhand how
to have ethtool report "true" instead.

But this is good step in the right direction.

base-commit: 1c273e10bc0cc7efb933e0ca10e260cdfc9f0b8c