Some multigig SFPs from RollBall and Hilink do not expose functional
MDIO access to the internal PHY of the SFP via I2C address 0x56
(although there seems to be read-only clause 22 access on this address).
Instead these SFPs PHY can be accessed via I2C via the SFP Enhanced
Digital Diagnostic Interface - I2C address 0x51. The SFP_PAGE has to be
selected to 3 and the password must be filled with 0xff bytes for this
PHY communication to work.
This extends the mdio-i2c driver to support this protocol by adding a
special parameter to mdio_i2c_alloc function via which this RollBall
protocol can be selected.
Signed-off-by: Marek Behún <kabel@kernel.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of configuring the I2C mdiobus when SFP driver is probed,
create/destroy the mdiobus before the PHY is probed for/after it is
released.
This way we can tell the mdio-i2c code which protocol to use for each
SFP transceiver.
Move the code that determines MDIO I2C protocol from
sfp_sm_probe_for_phy() to sfp_sm_mod_probe(), where most of the SFP ID
parsing is done. Don't allocate I2C bus if no PHY is expected.
Signed-off-by: Marek Behún <kabel@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In preparation for moving all MDIO drivers into drivers/net/mdio, move
the mdio-i2c header file into include/linux/mdio so it can be used by
both the MDIO driver and the SFP code which instantiates I2C MDIO
busses.
v2:
Add include/linux/mdio
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Marek Behún