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From: b.K.il.h.u+tigbuh@gmail.com
Date: Thu, 4 Jan 2024 10:07:51 +0100
Message-ID: <CAPuHQ=GSuKW5=T0GXXCq7Pf9jw=zcEnms-fEJey68QUWH1ishQ@mail.gmail.com>
Subject: Re: WiF Transmit Power Control (TPC) Regulatory Requirements?
To: wens@kernel.org
Cc: Seth Forshee <sforshee@kernel.org>, Kalle Valo <kvalo@codeaurora.org>, 
	Johannes Berg <johannes@sipsolutions.net>, 
	wireless-regdb <wireless-regdb@lists.infradead.org>, 
	linux-wireless <linux-wireless@vger.kernel.org>
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You can find a wording in most such regulations that if TPC is not
supported, the maximal TX power must be reduced by 3 dBmW. Hence in
all such cases, the entries in db.txt contain 3 less than the maximum.

If, on the other hand, you know of a country that specifies that
devices lacking TPC may not use the band at all, all such band entries
must be omitted (commented out along with a URL).

On Thu, Jan 4, 2024 at 6:59=E2=80=AFAM Chen-Yu Tsai <wens@kernel.org> wrote=
:
>
> Hi folks,
>
> I wanted to clarify the current state of things.
>
> As far as I know the kernel doesn't have facilities to support TPC or
> transmit power control, nor does the wireless-regdb database. And so
> in the database we would either omit rules that require TPC, or include
> alternative rules (as specified by local regulations) not requiring TPC.
> Am I right?
>
> This came up recently with regulatory changes for Singapore and Armenia.
>
> For Singapore [1], the 5.250 =E2=80=93 5.350 GHz range has provisions tha=
t allow
> usage without TPC at a lower power, but the 5.470 =E2=80=93 5.725 GHz doe=
s not.
>
> For Armenia [2], the updated text (translated by Google Translate) as I
> read it requires TPC for all 5 GHz channels.
>
>
> Thanks
> ChenYu
>
> [1] https://www.imda.gov.sg/-/media/imda/files/regulation-licensing-and-c=
onsultations/ict-standards/telecommunication-standards/radio-comms/imdatssr=
d.pdf
> [2] https://www.arlis.am/DocumentView.aspx?DocID=3D181829
>