What i find interesting is that you and the other resent requester are
using the same user space tool. If you implement C45 over C22 in that
tool, you get your solution, and it will work for older kernels as
well. Also, given the diverse implementations of this IOTCL, it
probably works for more drivers than just those using phy_mii_ioctl().
Do you mean change uapi, like
add mdio_phy_id_is_c45_over_c22() and
flag #define MDIO_PHY_ID_C45_OVER_C22 0x4000?
No, i mean user space implements C45 over C22. Make phytool write
MII_MMD_CTRL and MII_MMD_DATA to perform a C45 over C22.