[PATCH] Revert "ath: add support for special 0x0 regulatory domain"

[Alvin Sipraga]

Hi,

On 10/30/20 8:20 AM, Jouni Malinen wrote:
> So the issue is in not being able to operate an AP on the 5 GHz band?
> That sounds like the expected behavior for any device that has not
> been calibrated and provisioned for a specific country where
> regulatory rules allow operation on the 5 GHz band. I understand that
> this may look like a regression since the commit removed
> functionality, but it feels like a bug fix to me since that
> functionality should not have been enabled by default in the first
> place. The goal here is to avoid inappropriate operation on the band
> without explicit configuration to enable such operation. In AP
> devices, the device should have been provisioned for a specific
> country to be able to enforce the correct frequency range
> restrictions. The safe default for a device that does not have such
> explicit configuration within the WLAN component itself is to use the
> world roaming mode which prevents initialization of radiation (i.e.,
> does not allow AP mode to be started but allows station mode operation
> to connect to an already started AP) on the 5 GHz band.

This explanation makes perfect sense, but are you sure that that is what 
the 0x0 regulatory domain means? For example the pages [1][2] state 
unequivocally that 0x0 means US.

If we assume 0x0 = US, do you agree that an EEPROM programmed with 0x0 
should imply that the device is suitably calibrated for operation in the 
United States, and as such should permit initiating radiation on the 5 
GHz band (etc.)? Or have I missed something?

I also tried to get the patch in question reverted based on this 
rationale, see [3] for more info. I hope somebody can help clear up this 
misunderstanding, since it seems to me that the main issue is: what is 
the true meaning of 0x0?

Btw, the hardware that Félix is referring to does have an FCC ID[4] and 
seems to be suitably certified for the US.

Kind regards,
Alvin

[1] 
https://wireless.wiki.kernel.org/en/users/drivers/ath#the_0x0_regulatory_domain
[2] 
https://web.archive.org/web/20150117040022/http://article.gmane.org/gmane.linux.kernel.wireless.general/38410
[3] 
https://patchwork.kernel.org/project/ath10k/patch/20200730124923.271429-1-alsi@bang-olufsen.dk/
[4] https://fccid.io/TK4WLE900VX