Return-path: Received: from mail-pz0-f190.google.com ([209.85.222.190]:40677 "EHLO mail-pz0-f190.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755966Ab0A0TNc (ORCPT ); Wed, 27 Jan 2010 14:13:32 -0500 Received: by pzk28 with SMTP id 28so2179062pzk.4 for ; Wed, 27 Jan 2010 11:13:31 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <1264618781.8619.31.camel@wwguy-ubuntu> References: <1264511993.25642.9.camel@johannes.local> <43e72e891001271001r2cc39da4ka00a3eef06f6e139@mail.gmail.com> <1264615477.8619.20.camel@wwguy-ubuntu> <43e72e891001271014j667221bqa11d56f3a68f6099@mail.gmail.com> <1264616062.8619.22.camel@wwguy-ubuntu> <43e72e891001271025s27bbe25cs3c999a885551a4e7@mail.gmail.com> <1264618781.8619.31.camel@wwguy-ubuntu> From: "Luis R. Rodriguez" Date: Wed, 27 Jan 2010 11:13:11 -0800 Message-ID: <43e72e891001271113k6dad9004v5a17c705ae51aa2f@mail.gmail.com> Subject: Re: [PATCH] mac80211: wait for beacon before enabling powersave To: "Guy, Wey-Yi" , Lennert Buytenhek Cc: Johannes Berg , "linville@tuxdriver.com" , "kalle.valo@iki.fi" , "linux-wireless@vger.kernel.org" , "j@w1.fi" , "buytenh@wantstofly.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Jan 27, 2010 at 10:59 AM, Guy, Wey-Yi wrote: > On Wed, 2010-01-27 at 10:25 -0800, Luis R. Rodriguez wrote: >> On Wed, Jan 27, 2010 at 10:14 AM, Guy, Wey-Yi wrote: >> > On Wed, 2010-01-27 at 10:14 -0800, Luis R. Rodriguez wrote: >> >> On Wed, Jan 27, 2010 at 10:04 AM, Guy, Wey-Yi wrote: >> >> > On Wed, 2010-01-27 at 10:01 -0800, Luis R. Rodriguez wrote: >> >> >> On Tue, Jan 26, 2010 at 5:19 AM, Johannes Berg >> >> >> wrote: >> >> >> > Because DTIM information is required for powersave >> >> >> > but is only conveyed in beacons, wait for a beacon >> >> >> > before enabling powersave, and change the way the >> >> >> > information is conveyed to the driver accordingly. >> >> >> > >> >> >> > mwl8k doesn't currently seem to implement PS but >> >> >> > requires the DTIM period in a different way; after >> >> >> > talking to Lennert we agreed to just have mwl8k do >> >> >> > the parsing itself in the finalize_join work. >> >> >> >> >> >> Not sure if this is merged yet. If not it might be good to add to the >> >> >> commit log a brief about the impact of the fix for distribution >> >> >> purposes looking to cherry pick some fixes that may cure some issues. >> >> >> >> >> >> The impact of this fix is that the DTIM settings of > 1 would now be >> >> >> respected in the odd situation a beacon would not be received prior to >> >> >> association. Ensuring we use a higher DTIM would mean saving more >> >> >> power as it would mean we can sleep longer. >> >> >> >> >> >> This is not propagated to stable but if it turns out this can enhance >> >> >> power save since DTIM might usually be > 1 and the race may be more >> >> >> common than we expected we may need a respective stable solution. >> >> >> >> >> > >> >> > It will be nice to see a respective solution for stable since this >> >> > impact power save which is very important for certain platform. >> >> >> >> Well how about your patch for stable then? >> >> >> > if ok with you and Johannes, I will like to see it happen, the only >> > issue is, my patch only address iwlwifi but not mwl8k. >> >> Oh, what was the issue with your patch and mwl8k? >> > the patch will call drv_config() and ieee80211_recal_ps() > mwl8k driver did not implement PS function, but do require dtim for > another reason Lennert, why does it need it if it does not implement the PS function? Firmware API? What would happen if its not passed? Luis