Re: [RFC 1/2] nl80211: add common API to configure SAR power limitations.

[Kalle Valo <kvalo@codeaurora.org>]

Brian Norris <briannorris@chromium.org> writes:

> + ath10k
>
> [ I realize I replied to the "wrong" RFC v1; I fell trap to Kalle's note:
>
> "When you submit a new version mark it as "v2". Otherwise people don't
> know what's the latest version." ]
>
> On Tue, Nov 3, 2020 at 11:32 PM Carl Huang <cjhuang@codeaurora.org> wrote:
>> On 2020-11-04 10:00, Brian Norris wrote:
>> > What are the ABI guarantees around a given driver/chip's 'sar_capa'?
>> > Do we guarantee that if the driver supports N ranges of certain bands,
>> > that it will always continue to support those bands?
> ...
>> For a given chip(at least a QCOM chip), we don't see that the
>> range will grow or change.
>
> That's good to know. But that's not quite the same as an ABI guarantee.

I'm not sure if I understood Brian's question correctly, but I have
concerns on the assumption that frequency ranges never change. For
example, in ath10k we have a patch[1] under discussion which adds more
channels and in ath11k we added 6 GHz band after initial ath11k support
landed. And I would not be surprised if in some boards/platforms a
certain band is disabled due to cotting costs (no antenna etc). My
preference is to have a robust interface which would be designed to
handle these kind of changes.

[1] [PATCH] ath10k: enable advertising support for channels 32, 68 and 98

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