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Subject: Re: [RFC] mac80211_hwsim: notify user-space about channel change.
From: Johannes Berg <johannes@sipsolutions.net>
To: Ben Greear <greearb@candelatech.com>
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Date: Wed, 15 Apr 2015 11:33:20 +0200
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On Tue, 2015-04-14 at 08:55 -0700, Ben Greear wrote:

> > True, although I'd like to see the multi-channel issue addressed better.
> 
> I need a hint or two on what exactly you want changed in my patch to
> address your request, or maybe you or someone else can just address
> the issue in follow-on patches?

So right now you're basically saying to userspace "switch to channel X".
But that's not really how the more generic system works, that's more
"start using channel X (ctx=1)" / "stop using channel X (ctx=1)" /
"change channel to X (ctx=1)" and similar.

It seems to me that such an API should probably be the only API to
userspace. The non-chanctx case in hwsim could simply fake it by
starting with "start using channel X (ctx=0)" and then changing that
channel all the time.

The issue is that with your patch in this can't be addressed in
follow-on patches as it fixes the userspace API.

johannes