Return-path: Received: from mail.candelatech.com ([208.74.158.172]:43268 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753946Ab1BFVHY (ORCPT ); Sun, 6 Feb 2011 16:07:24 -0500 Message-ID: <4D4F0D83.4040401@candelatech.com> Date: Sun, 06 Feb 2011 13:07:15 -0800 From: Ben Greear MIME-Version: 1.0 To: Daniel Halperin CC: Felix Fietkau , "linux-wireless@vger.kernel.org" Subject: Re: Scanning and channel types. References: <4D4EF004.3040109@candelatech.com> <4D4EF99D.5020601@openwrt.org> <4D4EFC76.6090000@candelatech.com> <4D4EFD87.4010005@openwrt.org> <4D4EFF68.9060101@candelatech.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 02/06/2011 12:23 PM, Daniel Halperin wrote: > Could be rate selection. > > Ben, a sanity check: is it possible for the device to be associated > to an "HT-Only" AP and thus not be able to sent NO_HT packets? Could > that be why there might need to be a channel change sometimes? I don't know. The code and comments in ieee80211_set_channel_type make me think that it's always possible to send NO_HT packets regardless of hardware's channel type. One thing I haven't figured out yet: What actually tells the hardware to send NO_HT v/s HT20 v/s HT40, etc. I have previously tested HT20 STAs concurrent with HT40 stas, and both can send/receive at once while the hardware stays in HT40 mode. Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com