Return-path: Received: from mtiwmhc13.worldnet.att.net ([204.127.131.117]:62688 "EHLO mtiwmhc13.worldnet.att.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750872AbYGARNS (ORCPT ); Tue, 1 Jul 2008 13:13:18 -0400 Message-ID: <486A65F5.5030909@lwfinger.net> (sfid-20080701_191321_900614_13EED3C3) Date: Tue, 01 Jul 2008 12:14:29 -0500 From: Larry Finger MIME-Version: 1.0 To: Johannes Berg CC: Henrique de Moraes Holschuh , Michael Buesch , Adel Gadllah , linux-wireless@vger.kernel.org, stefano.brivio@polimi.it, "John W. Linville" , Ivo van Doorn Subject: Re: [PATCH/RFC] b43: remove input device usage for rfkill References: <6cf6b73e0807010255x1f2d8a21m8ed3e712012ea757@mail.gmail.com> <200807011227.15805.mb@bu3sch.de> <20080701143439.GA6962@khazad-dum.debian.net> <1214923097.3462.0.camel@johannes.berg> <20080701165036.GB6962@khazad-dum.debian.net> <1214931676.3462.5.camel@johannes.berg> In-Reply-To: <1214931676.3462.5.camel@johannes.berg> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: Johannes Berg wrote: > On Tue, 2008-07-01 at 13:50 -0300, Henrique de Moraes Holschuh wrote: >> On Tue, 01 Jul 2008, Johannes Berg wrote: >>>> 1. It has an input pin that sometimes people connect buttons/switches >>>> to. >>>> >>>> Does that input pin act as an input for a FLIP-FLOP (and that flip-flop >>>> output is the hardware rfkill line), or is it the hardware rfkill line >>>> itself? >>> Neither. It's not hw kill, but it's not just edge detect either, it does >>> have 'kill' and 'not kill' states. >> What exactly the input pin does? what exactly the hardware does when >> the input pin state changes? > > The hardware does nothing, it just sets a bit high or low depending on > the input pin. On my HP laptop using the RFKILL code currently in wireless-testing, sliding the "Wireless switch" results in b43_rfkill_poll being called. It then issues KEY_WLAN press and release events. This changes the state of the wireless light and the contents of a read-only bit in the status register of the device. I believe that if this bit is off, the radio is blocked by the hardware. Larry