On Tuesday 20 December 2016 17:56:58 Tony Lindgren wrote:

* Kalle Valo [off-list ref] [161220 03:47]:

quoted

Arend Van Spriel [off-list ref] writes:

quoted

On 18-12-2016 13:09, Pali Rohár wrote:

quoted

File wl1251-nvs.bin is provided by linux-firmware package and
contains default data which should be overriden by model
specific calibrated data.

Ah. Someone thought it was a good idea to provide the "one ring
to rule them all". Nice.

Yes, that was a bad idea. wl1251-nvs.bin in linux-firmware.git
should be renamed to wl1251-nvs.bin.example, or something like
that, as it should be only installed to a real system only if
there's no real calibration data available (only for developers to
use, not real users).

Makes sense to me. Note that with the recent changes to wlcore, we
can now easily provide board specific calibration firmware simply by
adding a new compatible value. So for n900, we could have something
like compatible = "ti,wl1251-n900" and have it point to n900
specific calibration file wl1251-nvs-n900.bin. Of course this won't
help with the mac address, or any of the device specific data..

That is assuming the calibration values are the same for each similar
device and don't have to be generated for each device. And naturally
wl1251 needs simlar changes done to make use of devices specific
calibration files.

Regards,

Tony

As wrote in another thread "wl1251 NVS calibration data format" 
calibration data for wl1251 (wl1251-nvs.bin) contains also MAC address, 
which kernel sends to wl1251 chip. Kernel just do not use it.

So... my idea now is:

1) extend request_firmware function family with ability to use userspace 
helper first and fallback to VFS

2) teach wl1251.ko to parse MAC address from wl1251-nvs.bin and use it 
(in case it is not empty or 00:00:20:07:03:09 which is in that example 
linux-firmware package)

3) write Nokia n900 specific userspace helper for providing data when 
kernel requests wl1251-nvs.bin. So userspace helper reads MAC address 
and calibration data from CAL, place MAC address into calibration data 
and send put it into kernel.

Are you OK with this idea?

-- 
Pali Rohár
pali.rohar@gmail.com