Return-path: Received: from nbd.name ([46.4.11.11]:41438 "EHLO nbd.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753325Ab1DFQYX (ORCPT ); Wed, 6 Apr 2011 12:24:23 -0400 Message-ID: <4D9C93B0.5050806@openwrt.org> Date: Wed, 06 Apr 2011 18:24:16 +0200 From: Felix Fietkau MIME-Version: 1.0 To: Rajkumar Manoharan CC: linville@tuxdriver.com, linux-wireless@vger.kernel.org Subject: Re: [PATCH v3] ath9k_hw: Fix instable target power control b/w CCK/OFDM References: <1302106372-4622-1-git-send-email-rmanoharan@atheros.com> In-Reply-To: <1302106372-4622-1-git-send-email-rmanoharan@atheros.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Sender: linux-wireless-owner@vger.kernel.org List-ID: On 2011-04-06 6:12 PM, Rajkumar Manoharan wrote: > The problem is that when the attenuation is increased, > the rate will start to drop from MCS7 -> MCS6, and finally > will see MCS1 -> CCK_11Mbps. When the rate is changed b/w > CCK and OFDM, it will use register desired_scale to calculate > how much tx gain need to change. > > The output power with the same tx gain for CCK and OFDM modulated > signals are different. This difference is constant for AR9280 > but not AR9285/AR9271. It has different PA architecture > a constant. So it should be calibrated against this PA > characteristic. > > The driver has to read the calibrated values from EEPROM and set > the tx power registers accordingly. > > Cc: Felix Fietkau > Signed-off-by: Rajkumar Manoharan Acked-by: Felix Fietkau Thanks, - Felix