[PATCH net 0/2] stmmac: fix ETHQOS SerDes interface handling

[Thomas Karpiniec]

This series fixes gigabit connectivity with ETHQOS and a QCA8081 PHY on
an IQ-8275 EVK, along with an error-propagation bug found while reviewing
the same configuration path. The first patch passes platform mac_finish()
errors to phylink. The second advertises the supported SerDes interfaces
so that phylink retains the PHY's lower-speed copper modes.

This revision was built into a WendyOS test image and booted on the
IQ-8275 EVK. Tests covered boot at 1Gbps and 2.5Gbps, physical cable swaps
in both directions, stable carrier, and traffic at 1Gbps. Injecting
-ETIMEDOUT at the platform callback held carrier down at both speeds;
restarting the interface after disabling injection recovered it. This
was a synthetic callback error, not a physical SerDes failure.

The tests used regulator_ignore_unused: without it, the upstream board
tree repeatedly lost PCS link. The vendor tree has a REFGEN always-on
workaround absent from this tree. No extra kernel or device-tree patches
were applied for these tests.

Sparse reported no findings in the changed code.

Patch 2 uses SerDes APIs introduced in v7.1. Older affected kernels
need an adapted backport rather than a straight cherry-pick.

Thomas Karpiniec (2):
  net: stmmac: propagate platform mac_finish errors
  net: stmmac: qcom-ethqos: advertise supported SerDes interfaces

 .../ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c    | 22 ++++++++++++++++++++++
 drivers/net/ethernet/stmicro/stmmac/stmmac_main.c  |  4 ++--
 2 files changed, 24 insertions(+), 2 deletions(-)


base-commit: ceac0de741bfb47ca255eee075257b3bb31f0651
-- 
2.50.1 (Apple Git-155)