Re: [PATCH 3/5] firmware: revamp firmware documentation

Johannes Berg
2016-12-16T09:34:53Z

> > > Maybe it is worth to mention, that the calibration data is unique
> > > to a given chip, so it is individual. That is you would need to
> > > built for each device you sell its own kernel.
> >
> > It's commonly unique to the device model, not a chip. The same chip
> > can be used with different power amplifiers or different antennas.
> > That's why you need model (board) specific calibration data.
>
> From what I recall in my 802.11 days this can be often very specific
> per *batch* of cards not just chip/device model, so this depends on
> the manufacturing process and date.

Yes, it can be a per-device calibration done in the factory, and then
the data is programmed into the device after that calibration - but if
the device is something like a router (not a standalone NIC) then the
data might still go through request_firmware() or similar in the end.

johannes