[net-next PATCH v2 0/3] net: phy: as21xxx: toggle In Band feature support

[Christian Marangi <ansuelsmth@gmail.com>]

This is a new variant of the previous submitted patch adding a similar
feature.

Old Aeonsemi Firmware permitted only to enable or disable In Band
support and it couldn't be disabled after (or there wasn't a
way to detect the current state of it)

As suggested by Russell this was bad Implementation. Some talk
with Aeonsemi permitted to release a new firmware with correct
implementation.

This series adds support for this if new firmware (1.9.1+) is
used. On the new firmware, 2 new IPC command are introduced
to GET the current state of DPC RA (Rate Adaption) or SET it.
(DPC RA is effectively In Band mode)

It was verified on the same scenario and can confirm it works
as expected. (Airoha AN7581/AN7583 with and without In Band
mode) (If PCS is set to In Band and PHY isn't then no
connection, so it's easy to verify correct functionality of
this)

The new firmware is currently submitted to linux-firmware
awaiting it to be merged.

For old firmware to save on compatibility we still enable
In Band by default (this is what the current driver do)

This was discovered to be needed in some scenario as is effectively
the most compatible featureset.

On a BananaPi R4 Pro, one of the 2 AS21xxx PHY is connected to
one of the Switch port and such switch supports only In Band when
set to USXGMII (assuming the Switch expect an SFP module to be
attached where in absence of i2c or MDIO line In Band is always
required)

Changes v2:
- Rework to new firmware version IPC command
- Add DBG IPC command
- Store FW major/minor version

Christian Marangi (3):
  net: phy: as21xxx: save firmware version major/minor version
  net: phy: as21xxx: add support for DBG command
  net: phy: as21xxx: fill in inband caps and better handle inband

 drivers/net/phy/as21xxx.c | 316 +++++++++++++++++++++++++++++++++-----
 1 file changed, 280 insertions(+), 36 deletions(-)

-- 
2.51.0