Return-path: Received: from xc.sipsolutions.net ([83.246.72.84]:46196 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753324AbZDBBwb (ORCPT ); Wed, 1 Apr 2009 21:52:31 -0400 Subject: Re: How to implement power save mode From: Johannes Berg To: Charles Gordon Cc: linux-wireless@vger.kernel.org In-Reply-To: <86201b3f0904011350o5b3fb48g811b57b3c4a1e602@mail.gmail.com> (sfid-20090401_225051_265370_58404EAB) References: <86201b3f0904011350o5b3fb48g811b57b3c4a1e602@mail.gmail.com> (sfid-20090401_225051_265370_58404EAB) Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-xfwt+VM5e7iEOTLg+6wT" Date: Thu, 02 Apr 2009 03:51:57 +0200 Message-Id: <1238637117.4141.3.camel@johannes.local> (sfid-20090402_035235_334633_5852DBA9) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: --=-xfwt+VM5e7iEOTLg+6wT Content-Type: text/plain Content-Transfer-Encoding: quoted-printable Charles, > How is the IEEE80211_CONF_PS flag in the ieee80211_conf structure > used? Does it indicate when the low level driver should be turning > the transceiver on and off, or is it just an indication of whether or > not the driver should be running in power save mode? >=20 > If the low level driver is suppose to implement the bulk of power save > mode, then how is it suppose to get information like how long the > sleep periods are suppose to be? Does mac80211 provide utility > functions for parsing beacons to check for TIM and DTIM elements? >=20 > Any help you can provide would be appreciated. You really need to read 802.11-2007, and understand how powersave mode works. If you need software to check the beacons for (D)TIM, then you can't really do powersave mode. You could hack around that if your hardware provides an interrupt before the TBTT -- but that is very fragile and I wouldn't recommend it. If your hardware design cannot support powersave mode you'll just have to live without it. johannes --=-xfwt+VM5e7iEOTLg+6wT Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Comment: Johannes Berg (powerbook) iQIcBAABAgAGBQJJ1Bo7AAoJEKVg1VMiehFYMWEP/jEgzzQVPEqxHS8IzdWciiuT US6OK8q5iEjOG+6TPoYrH9ConA3RxVt775Hz0T9VBWTo5362nVsmdd32inF6X7Ze 3xd4BRayr9ZJgoRSrnl2vIu422g2rU5hwC/ILrVNyV2UFkxV5rHjfAtSd/CbSe1F UFWtGjRX6DJRrs4+p5nY2rXeT1xfu4jQ5j3Cgk1micEebFO9S8e0aTgNSr2k0xwA G8jUJ/y6uCnc6v6G3GZCOmo/PE+esSA8lwtFal7XGPGoOoUgH8NzxkfsHUqM74tS /O9cqBVX2Ah92OEQVLigM6kwxcmclTPDh0yslSzE0wRWUDL08Pf5Srr7vwex8Num EJ129HGAHVpBIZooljwERRLUggN7ysXxvQH7xP33V8JKBQ7yOxXdTflicE4OM5Ep zuV7AtdtYzsuWszEwAnI1dGxaXfBdFNqIe2lY4mrqZ5PrfDdKgh6wTdYTF2Wf+YH zaYBv/tPg0xpaNax23mQwo+Tc3h3zKY+I9vSJtpTKmnfZc+sg4QOFxyvvJEt0qpU vDOlvtFNyf/7uMIx0DFPIWh6pOXFUpLIsfbECDrlafNxQdfg5bM6vcu1QkdJZuX1 2AUa4QIXuARApyHu9R0vkA617JPlw9mdxLam1JnsMjTiJnziqInu/Bz0olrH02lU U1T1IvlXTag98BTC4JRT =WJr2 -----END PGP SIGNATURE----- --=-xfwt+VM5e7iEOTLg+6wT--