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Subject: Re: [PATCH] iwlwifi: add option to disable 5GHz band
From: Marcel Holtmann <marcel@holtmann.org>
To: Johannes Berg <johannes@sipsolutions.net>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>,
	Intel Linux Wireless <ilw@linux.intel.com>,
	linux-wireless@vger.kernel.org
Date: Thu, 19 Apr 2012 17:56:54 +0200
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Hi Johannes,

> > There are various problems happened on 5GHz band not observed on
> > 2.4 GHz (microcode errors, queue stuck, etc... ) . Also roaming
> > between 5GHz AP and 2GHz does not work very well. To workaround
> > the problems add option to disable 5GHz support. This will help
> > on environments where APs are dual-band, and devices will not try
> > to associate on band where issues happen.
> 
> Would it make sense to somehow do this in cfg80211? Today, our driver 
> may be the only one having this problem (which I've never really heard 
> about?), but is it always going to be?

honestly I have seen 5GHz problems with our driver multiple times. I
always ended up disabling 5GHz support in the AP since I rarely have
time to debug this. It only happens after long time of operation for me,
but was like super annoying all the time.

And I had similar issues with N support.

I would personally be fine with a global debugfs option within cfg80211
to disable it.

Regards

Marcel