Re: [PATCH net-next v2 2/2] nfc: s3fwrn5: support the S3NRN4V variant

Hello David,

On 19/07/2026 16:56, David Heidelberg wrote:
> now it makes more sense to me, feel free to name it as calibration
> data.

Will do -- v3 will say "RF calibration data" in the commit message and
comments.

> I would suggest to introduce something as a calibration-variant (see
> ath10k code).
>
> If I understand right, firmware location path could look like
>
> default path + driver vendor and model + device vendor and model +
> revision
>
> /lib/firmware/ + Samsung/s3nrn4v/ + Fairphone/FP5/hwrevision.bin

That layout makes sense to me. My inclination for v3:

- request the files from a chip-scoped directory:
  samsung/s3nrn4v/hwreg.bin + samsung/s3nrn4v/swreg.bin (the existing
  parts' sec_s3fwrn5_rfreg.bin is untouched);

- an optional samsung,calibration-variant string property (modelled
  on ath10k's qcom,calibration-variant) that, when set, makes the
  driver try a device-scoped location first, e.g.
  samsung/s3nrn4v/fairphone-fp6/hwreg.bin, falling back to the bare
  files above.

The variant lookup can also be added compatibly later, once a second
S3NRN4V design (or a diverging FP6 revision) actually appears -- so
if you'd rather keep v3 minimal, I'd do only the directory move now
and add the property when first needed. Either works for me.

So far I have seen no evidence of per-revision or per-region variants
on the FP6: the only difference I have identified between my two
units' tables is the vendor software release (build-date stamps).
But Fairphone would know better.

> /cc Luca here, as he may know more about the different configuration
> data shipped.

Luca, two questions your way:

- do FP6 hardware revisions (or regional SKUs) ship different NFC
  hwreg/swreg tables, or is it one set per software release?

- could Fairphone submit these tables to linux-firmware? I assume
  the redistribution question sits with Fairphone/Samsung, and having
  them there would make NFC work out of the box on mainline.

> We should assume the configuration will be shipped with
> linux-firmware at some point.

Agreed -- that is exactly why I'd like to settle the path scheme now.

v3 is otherwise ready, including the Fairphone 6 DT patch; rather
than sending it right away as I said earlier today, I'll give this
a few days for Luca's input and then send it.

Thanks,
Jorijn