Return-path: Received: from mail-qy0-f174.google.com ([209.85.221.174]:65125 "EHLO mail-qy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750782AbZKPRoX (ORCPT ); Mon, 16 Nov 2009 12:44:23 -0500 Received: by qyk4 with SMTP id 4so2759257qyk.33 for ; Mon, 16 Nov 2009 09:44:28 -0800 (PST) From: Ivo van Doorn To: Josef Bacik Subject: Re: [PATCH] rt2800: do not enable tbtt unless we are in a beacon mode Date: Mon, 16 Nov 2009 18:44:24 +0100 Cc: linux-wireless@vger.kernel.org, users@host1.serialmonkey.com, John Linville References: <20091116023317.GA6331@localhost.localdomain> In-Reply-To: <20091116023317.GA6331@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Message-Id: <200911161844.25162.IvDoorn@gmail.com> Sender: linux-wireless-owner@vger.kernel.org List-ID: [ Added john to CC list ] On Monday 16 November 2009, Josef Bacik wrote: > Please be gentle, I'm a fs developer and this is my first foray into drivers, as > I'm tired of building ralinks driver everytime I update my kernel. Whenever I > load the rt2800pci driver my box bogs down, and a few printk's later I > discovered its because I was getting 10's of thousands of TBTT interrupts a > second. I discovered this was because we were setting the beacon timer to 0, > which is apparently what TBTT keys off of. It seems to me that we should only > be enabling TBTT when we are in a beacon transmitting mode, which from what I > can tell is in AD-HOC and other such modes where the mac80211 layer would have > given us a proper beacon_int to set the beacon timer to instead of 0. So this > is my fix, only enable TBTT if our sync mode is for beacon. This makes it so my > box doesn't die everytime I load the rt2800pci driver. Let me know if this is > acceptable, I just learned all these terms about 15 minutes ago via wikipedia, > so I really am not familiar with how this stuff is supposed to work. Thanks, > > Signed-off-by: Josef Bacik Good catch. Acked-by: Ivo van Doorn > --- > drivers/net/wireless/rt2x00/rt2800lib.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c > index eb6d129..e90d6fd 100644 > --- a/drivers/net/wireless/rt2x00/rt2800lib.c > +++ b/drivers/net/wireless/rt2x00/rt2800lib.c > @@ -560,7 +560,8 @@ void rt2800_config_intf(struct rt2x00_dev *rt2x00dev, struct rt2x00_intf *intf, > rt2800_register_read(rt2x00dev, BCN_TIME_CFG, ®); > rt2x00_set_field32(®, BCN_TIME_CFG_TSF_TICKING, 1); > rt2x00_set_field32(®, BCN_TIME_CFG_TSF_SYNC, conf->sync); > - rt2x00_set_field32(®, BCN_TIME_CFG_TBTT_ENABLE, 1); > + rt2x00_set_field32(®, BCN_TIME_CFG_TBTT_ENABLE, > + (conf->sync == TSF_SYNC_BEACON)); > rt2800_register_write(rt2x00dev, BCN_TIME_CFG, reg); > } >