From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail2.candelatech.com ([208.74.158.173]:37856 "EHLO mail2.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750810AbaEGMlG (ORCPT ); Wed, 7 May 2014 08:41:06 -0400 Message-ID: <536A29E0.4030208@candelatech.com> (sfid-20140507_144110_754167_4F98222A) Date: Wed, 07 May 2014 05:41:04 -0700 From: Ben Greear MIME-Version: 1.0 To: Johannes Berg CC: "linux-wireless@vger.kernel.org" Subject: Re: How to configure monitor devices for HT80? References: <5367E13C.2020208@candelatech.com> (sfid-20140505_211155_884363_141E505C) <1399317771.22235.23.camel@jlt4.sipsolutions.net> <53692240.5010001@candelatech.com> <1399453264.10517.6.camel@jlt4.sipsolutions.net> In-Reply-To: <1399453264.10517.6.camel@jlt4.sipsolutions.net> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 05/07/2014 02:01 AM, Johannes Berg wrote: > On Tue, 2014-05-06 at 10:56 -0700, Ben Greear wrote: > >> But, it seems if I have another vif up, it will fail, even if that >> vif is (should be?) using the exact same frequency. >> >> ./local/sbin/iw phy wiphy0 interface add moni0 type monitor >> ./local/sbin/ip link set dev moni0 up >> ./local/sbin/iw dev moni0 set freq 5180 80 5210 >> -> yields error: >> command failed: Device or resource busy (-16) > > You can't set the monitor frequency if you're using the hardware for > something else already. We could potentially allow that if the chandefs > are compatible, but that's getting into really messy territory so I'm > not sure I want to go there - if for example the other interface > switches bandwidth or even channel the monitor would usually simply > follow around. Ok, as long as I know why then the failure is not so concerning. Another question: if I create a monitor interface first, and successfully set it's frequency, what do I need to do to allow a station to move to a different frequency later? Thanks, Ben > > johannes > -- Ben Greear Candela Technologies Inc http://www.candelatech.com