From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from cpsmtpb-ews07.kpnxchange.com ([213.75.39.10]:4775 "EHLO cpsmtpb-ews07.kpnxchange.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750895Ab0DWPVa (ORCPT ); Fri, 23 Apr 2010 11:21:30 -0400 Message-ID: <4BD1BAF8.1060908@gmail.com> Date: Fri, 23 Apr 2010 17:21:28 +0200 From: Gertjan van Wingerde MIME-Version: 1.0 To: Helmut Schaa CC: John Linville , Ivo van Doorn , linux-wireless@vger.kernel.org, rt2x00 Users List Subject: Re: [PATCH] rt2x00: rt2800lib: disable HT40 for now as it causes reception problems References: <201004231505.29689.helmut.schaa@googlemail.com> In-Reply-To: <201004231505.29689.helmut.schaa@googlemail.com> Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: On 04/23/10 15:05, Helmut Schaa wrote: > Disable HT40 support for now as it causes rx problems with HT40 capable > 11n APs (when mac80211 enables HT40, rx is completely disfunctional). > > Once the rt2800 HT code is capable of using HT40 we should enable the > flag again. > > I only tested this patch with a rt305x SoC device, nevertheless the > patch disables HT40 also on PCI and USB rt2800 devices. > > Signed-off-by: Helmut Schaa I can confirm that this also helps for PCI and USB devices. With this patch applied all my rt28xx and rt30xx based devices starting working correctly. So, definately, Acked-by: Gertjan van Wingerde > --- > > Using this patch I was able to associate a rt305x SoC device with my 11n > capable AP using WPA and the connection basically works although I see lots > of retried frames when sniffing the wireless traffic. > > If someone already had success with rt2800 and HT40 capable APs we should > consider to only conditionally unset the HT40 flag for 305x SoC devices. > > drivers/net/wireless/rt2x00/rt2800lib.c | 5 ++++- > 1 files changed, 4 insertions(+), 1 deletions(-) > > diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c > index 2648f31..aa02ff6 100644 > --- a/drivers/net/wireless/rt2x00/rt2800lib.c > +++ b/drivers/net/wireless/rt2x00/rt2800lib.c > @@ -2318,8 +2318,11 @@ int rt2800_probe_hw_mode(struct rt2x00_dev *rt2x00dev) > else > spec->ht.ht_supported = false; > > + /* > + * Don't set IEEE80211_HT_CAP_SUP_WIDTH_20_40 for now as it causes > + * reception problems with HT40 capable 11n APs > + */ > spec->ht.cap = > - IEEE80211_HT_CAP_SUP_WIDTH_20_40 | > IEEE80211_HT_CAP_GRN_FLD | > IEEE80211_HT_CAP_SGI_20 | > IEEE80211_HT_CAP_SGI_40 |