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Subject: Re: [PATCHv3] cfg80211: add support for frequency interference event
From: Johannes Berg <johannes@sipsolutions.net>
To: "Luis R. Rodriguez" <mcgrof@do-not-panic.com>
Cc: Rajesh Chauhan <rajeshc@qca.qualcomm.com>,
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Date: Wed, 04 Dec 2013 09:20:04 +0100
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On Tue, 2013-12-03 at 17:35 +0100, Luis R. Rodriguez wrote:
> On Tue, Dec 3, 2013 at 2:25 PM, Johannes Berg <johannes@sipsolutions.net> wrote:
> >> + * @interference_source: enum nl80211_freq_interference_source_type
> >> + *   is used to specify source of interference.
> >
> > Do we expect that different sources would be treated differently? If
> > not, what use is this?
> 
> That was because of my nagging, without such a field the type of
> interference would be completely ambiguous and we'd have no users on
> the Linux kernel of this API,

Wait, we have no users for this API? Forget it then - I thought you were
going to post a patch soon. I guess I should have learned by now not to
trust QCA with this.

I'll drop this until I see a patch using it.

> making anyone wonder WTF this is used
> for, except for those poking on some random non upstream driver.
> Additionally from a technical perspective having this information is
> purely informative at this point given that hostapd would be expected
> to be treating the cellular based source of interference as avoidance
> hints. It does leave open, for example, drivers with other types of
> future sources of advisories to simply piggy on top of this when the
> source of interference is coming from the 802.11 devices somehow.

I think we could also just document the kind of things it should be used
for, rather than having a useless (and potentially fake, since nobody
cares) value.

johannes