Re: [PATCH v2] eeprom/optoe: driver to read/write SFP/QSFP/CMIS EEPROMS

On Mon, Feb 15, 2021 at 11:38:21AM -0800, Don Bollinger wrote:

optoe is an i2c based driver that supports read/write access to all
the pages (tables) of MSA standard SFP and similar devices (conforming
to the SFF-8472 spec), MSA standard QSFP and similar devices (conforming
to the SFF-8636 spec) and CMIS and similar devices (conforming to the
Common Management Interface Specfication).

Hi Don

Please make sure you Cc: netdev. This is networking stuff.

And we have seen this code before, and the netdev Maintainers have
argued against it before.

These devices provide identification, operational status and control
registers via an EEPROM model.  These devices support one or 3 fixed pages
(128 bytes) of data, and one page that is selected via a page register on
the first fixed page.  Thus the driver's main task is to map these pages
onto a simple linear address space for user space management applications.
See the driver code for a detailed layout.

I assume you have seen the work NVIDIA submitted last week? This idea
of linear pages is really restrictive and we are moving away from it.

The EEPROM data is accessible to user space and kernel consumers via the
nvmem interface.

ethtool -m ?

In the past, this code has been NACKed because it does not integrate
into the networking stack. Is this attempt any different?

Thanks
	Andrew