Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 21FE6C43381 for ; Thu, 14 Mar 2019 13:50:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EEC8F2184C for ; Thu, 14 Mar 2019 13:50:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727629AbfCNNuS (ORCPT ); Thu, 14 Mar 2019 09:50:18 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54532 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727394AbfCNNuQ (ORCPT ); Thu, 14 Mar 2019 09:50:16 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id A69A33091752; Thu, 14 Mar 2019 13:50:16 +0000 (UTC) Received: from localhost (unknown [10.43.2.106]) by smtp.corp.redhat.com (Postfix) with ESMTP id 40B5D17DC4; Thu, 14 Mar 2019 13:50:13 +0000 (UTC) Date: Thu, 14 Mar 2019 14:50:12 +0100 From: Stanislaw Gruszka To: Felix Fietkau Cc: linux-wireless@vger.kernel.org, Lorenzo Bianconi Subject: Re: [RFC] mt76: add 3dBm for reporting txpower also for 1x1 Message-ID: <20190314135011.GA15786@redhat.com> References: <1552484061-4647-1-git-send-email-sgruszka@redhat.com> <795dd253-53db-d837-4da6-6016a096cdc7@nbd.name> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <795dd253-53db-d837-4da6-6016a096cdc7@nbd.name> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Thu, 14 Mar 2019 13:50:16 +0000 (UTC) Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Wed, Mar 13, 2019 at 02:38:01PM +0100, Felix Fietkau wrote: > On 2019-03-13 14:34, Stanislaw Gruszka wrote: > > It's not clear for my why we should add 3dBm for 2x2 devices > > and not for 1x1. 3dBm looks rater like minimal txpower and > > hardware transmit at 3dBm + dev->txpower_cur / 2 . > > > > With the change reported txpower value are closer to regulatory > > values, but honestly I have no idea what should be reported. > > > > Perhaps also some better comment should be added. > > > > Signed-off-by: Stanislaw Gruszka > The reason why we add 3dBm is because using two chains to transmit in > the worst case (from regulatory point of view) doubles the transmit > power (= +3dBm). There's no reason to do the same for 1x1. Do we calculate and show correct txpower for mt76x0 then? I have mt76x0u 50:3e:aa:a6:5d:32 and iwlmvm 1c:1b:b5:23:cf:58 devices on one laptop at the same location connected to AP. RSSI values of both stations are quite similar: Station 50:3e:aa:a6:5d:32 (on wlan0) inactive time: 4971 ms rx bytes: 11383 rx packets: 97 tx bytes: 2764 tx packets: 17 tx retries: 3 tx failed: 1 signal: -55 [-65, -55] dBm signal avg: -57 [-65, -57] dBm tx bitrate: 65.0 MBit/s MCS 6 short GI rx bitrate: 6.0 MBit/s authorized: yes authenticated: yes preamble: long WMM/WME: yes MFP: no TDLS peer: no Station 1c:1b:b5:23:cf:58 (on wlan0) inactive time: 24261 ms rx bytes: 11320 rx packets: 121 tx bytes: 2274 tx packets: 11 tx retries: 0 tx failed: 1 signal: -52 [-60, -52] dBm signal avg: -54 [-59, -55] dBm tx bitrate: 6.5 MBit/s MCS 0 rx bitrate: 6.0 MBit/s authorized: yes authenticated: yes preamble: long WMM/WME: yes MFP: no TDLS peer: no On laptop txpower showed by iw for mt76x0u is 17 dBm , for iwlmvm is 22 dBm (this is value from mac80211, iwlwifi does not implement .get_txpower() callback). I do not consider this as big issue though, but can confuse some users. Apparently confuses me. Stanislaw