From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ti-edu.ch ([195.176.176.171]:22891 "EHLO ti-edu.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756057Ab2FZMK3 (ORCPT ); Tue, 26 Jun 2012 08:10:29 -0400 From: "Michal Kudelski" Subject: Re: carl9170 driver - reducing the output power To: "Christian Lamparter" Cc: Date: Tue, 26 Jun 2012 14:10:25 +0200 Message-ID: (sfid-20120626_141032_449144_09D7EAA1) In-Reply-To: <201206251933.10999.chunkeey@googlemail.com> References: <201206251933.10999.chunkeey@googlemail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: Dear Christian, Thank you for the response! Indeed, when I used the latest compat-wireless, I was able to control the output power. Now, another question arises: what is the lowest supported power level? Do you have any hardware specifications of AR9170 that would say what is the lowest power level supported by the hardware? With iw/iwconfig commands, the lowest achievable power is 1 dbm. But I'm thinking about modifying your code in order to write fixed values to the corresponding registers. And I need to know what to write into the registers in order to obtain the lowest possible power :-) . I know that there exist wifi cards that accept -12 dbm (e.g., Intel Pro-Wireless 2200 with ipw2200 driver under linux), so it would be really nice to know what I can get with Atheros... Cheers, Michal On Mon, 25 Jun 2012 19:33:10 +0200 Christian Lamparter wrote: > On Monday, June 25, 2012 12:38:50 PM Michal Kudelski >wrote: >> Thus, my question is: is the function of changing the >> txpower really supported? If it is, what steps should I >> take to make it work? I tried with ifconfig up/down when >>I >> change the txpower, but it does not change anything. >>Maybe >> I do something wrong? Do I use the correct versions of >>the >> firmware and the driver? > No special firmware or driver is required. Just as long > as the driver supports the feature. > >> I've noticed a patch related to this issue, published on >> 2012-01-27 by Christian Lamparter. It seems that it is >> included in my driver version, but maybe I'm wrong and I >> should apply some additional patch? >> >> We use NetGear WNDA3100(v1) hardware [Atheros >> AR9001U-(2)NG] and carl9170 driver >> (driverversion=3.0.0-21-generic firmware=1.9.2). > That's probably too old. The patch you are talking about > is not a -stable patch so it's not backported to 3.3.x > (or older) kernels. > > So, either you can upgrade to 3.4, use compat-wireless > > or backport the patch yourself (however, this could be >diffcult). > > Regards, > Christian