RE: [PATCH v2] net: add new QCA alx ethernet driver

This is why we require that portable, sane, interfaces are added to ethtool for
driver diagnostics.  That way users can perform a task in the same way
regardless of what hardware and driver are underneath.

I quite agree you on using ethtool to implement it. we did consider it. 
But ethtool has some limitation, for example, the NIC has built-in OTP (TWSI interface)
And Flash (External SPI interface),  their properties are quite different with EEPROM which
Ethtool supports.
To support such memory (OTP/Flash), we need additional input parameters.

Same situation exists in diagnostic utility. Ethtool only provide two options : offline & online
That's too gross to locate which part/module of the chip is malfunction. we also need 
more options to detect it.

that's why we finally selected a custom debugfs interface. 

Thanks
Xiong