[net-next,v3,0/2] net: phy: sfp: Add single-byte SMBus SFP access

Message

Maxime Chevallier March 14, 2025, 4:23 p.m. UTC

Hello everyone,

This is V3 for the single-byte SMBus support for SFP cages as well as
embedded PHYs accessed over mdio-i2c.

Discussions on the previous iteration raised some questions on the
ordering of the accesses (from Andrew), after further testing it still
seems correct to me, I can properly read EEPROMS and by hacking around,
read 16 bits values (although this is disabled anyways).

This series compared to V2 changes the approach used internally to use
the degraded mode (no hwmon), by setting the i2c_block_size to 1 and
re-using the logic already in place to deal with that.

As we now have 2 scenarios for 1-byte accesses (broken EEPROM that needs
to be accessed 1 byte at a time or single-byte SMBus), I've updated some
of the in-place error logs. Users should still be plenty warned and
made aware of the situation.

I also renamed the internal helpers to reflect that we use single-byte
accesses.

The rest was left untouched (I didn't have time yet to test around with
Rollball for example or 16-bits SMBus).

As I reworked patch 1, I dropped Sean's tested-by :(

V2 : https://lore.kernel.org/netdev/[e-mail]/
V1 : https://lore.kernel.org/netdev/[e-mail]/#t

@Maintainers: I already have a few series queued for review, let me know
if you prefer that I resend that one at a later time.

Maxime

Maxime Chevallier (2):
  net: phy: sfp: Add support for SMBus module access
  net: mdio: mdio-i2c: Add support for single-byte SMBus operations

 drivers/net/mdio/mdio-i2c.c | 79 ++++++++++++++++++++++++++++++++++-
 drivers/net/phy/sfp.c       | 82 +++++++++++++++++++++++++++++++++----
 2 files changed, 152 insertions(+), 9 deletions(-)