Return-path: Received: from mail.candelatech.com ([208.74.158.172]:48352 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753048Ab1AaRfe (ORCPT ); Mon, 31 Jan 2011 12:35:34 -0500 Message-ID: <4D46F2E2.3090905@candelatech.com> Date: Mon, 31 Jan 2011 09:35:30 -0800 From: Ben Greear MIME-Version: 1.0 To: Johannes Berg CC: "linux-wireless@vger.kernel.org" Subject: Re: Why is wmm_param required for HT40- in mlme.c References: <4D44F94F.8040707@candelatech.com> <1296380208.3616.0.camel@jlt3.sipsolutions.net> <4D45A128.6060905@candelatech.com> <1296471791.3812.7.camel@jlt3.sipsolutions.net> In-Reply-To: <1296471791.3812.7.camel@jlt3.sipsolutions.net> Content-Type: text/plain; charset=UTF-8; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 01/31/2011 03:03 AM, Johannes Berg wrote: > On Sun, 2011-01-30 at 09:34 -0800, Ben Greear wrote: >> On 01/30/2011 01:36 AM, Johannes Berg wrote: >>> On Sat, 2011-01-29 at 21:38 -0800, Ben Greear wrote: >>>> I tried to set up hostapd to do HT40-, but for whatever reason, >>>> it's not sending any wmm_param options, so the stations will not >>>> associate with HT40- enabled due to the check below. >>>> >>>> Is it really *reqired* that wmm_param exist to enable HT mode? >>>> >>>> From mlme.c: >>>> if (elems.ht_info_elem&& elems.wmm_param&& >>>> (sdata->local->hw.queues>= 4)&& >>>> !(ifmgd->flags& IEEE80211_STA_DISABLE_11N)) >>>> changed |= ieee80211_enable_ht(sdata, elems.ht_info_elem, >>>> cbss->bssid, ap_ht_cap_flags); >>> >>> 802.11n-2009 says it is required. >> >> Do you know the pertinent section, or some keywords to search for? I'm >> unable to find anything useful. > > No, I got confused. 802.11n says an HT STA is a QoS STA (5.2.9), but in > practice WMM is tested/certified instead of QoS. So maybe we can remove that check for wmm_param, but put in a printk to warn users that their AP is probably mis-configured? Thanks, Ben > > johannes -- Ben Greear Candela Technologies Inc http://www.candelatech.com