From mboxrd@z Thu Jan 1 00:00:00 1970 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=-5.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 0EDA8C04E53 for ; Wed, 15 May 2019 12:01:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D47FD2084A for ; Wed, 15 May 2019 12:01:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557921700; bh=hF+k8arQQBJmy+6LJc2q9QQ7r70YBE9Ie0gz7BV2xz0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=PpieIXX1kxICZM9xzxs8CeGdKiXc/AY7ZIg6o86AFpjIhMkSFOTn7pX35SgcF2bmC GpmkG1QO5G+Pd+fs8M/sSzbuX805xhSEnGdYU0r2yP6U7kHfOHcWSKYvLQou6vyp5s KIWsmHo93qMTaD/0kdKax/8aj7viCYjaMmQEJEl0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730018AbfEOMBk (ORCPT ); Wed, 15 May 2019 08:01:40 -0400 Received: from mail.kernel.org ([198.145.29.99]:49766 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730041AbfEOLNz (ORCPT ); Wed, 15 May 2019 07:13:55 -0400 Received: from localhost.localdomain (nat-pool-mxp-t.redhat.com [149.6.153.186]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 11C4020862; Wed, 15 May 2019 11:13:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557918834; bh=hF+k8arQQBJmy+6LJc2q9QQ7r70YBE9Ie0gz7BV2xz0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=BkwBIG3LelHE5JiqR6QSatS76wBERHK9WH79u8fiMDHeynMvWhwzwvSKEmtzZofzO KxABmNMVHRAAIrp3zhqLUc/qsJD73DhNBOmGmh6fSKtWnHy5kVy/PbQ3YwJM6rqau/ 7mEkw9BWe95OSBo1Wl4tqgIsHOVEPNCVlNHF7hEI= Date: Wed, 15 May 2019 13:13:49 +0200 From: Lorenzo Bianconi To: Stanislaw Gruszka Cc: Kalle Valo , nbd@nbd.name, lorenzo.bianconi@redhat.com, linux-wireless@vger.kernel.org Subject: Re: [PATCH] mt76: mt7603: add debugfs knob to enable/disable edcca Message-ID: <20190515111348.GC30757@localhost.localdomain> References: <0691acb931e963cb6028d4687cdd61032d0aaf52.1557591530.git.lorenzo@kernel.org> <87r293ugia.fsf@purkki.adurom.net> <20190513084127.GA3127@localhost.localdomain> <20190513094837.GB15694@redhat.com> <20190515093333.GA2333@redhat.com> <20190515094354.GA30757@localhost.localdomain> <20190515095440.GB3407@redhat.com> <20190515100343.GB30757@localhost.localdomain> <20190515103309.GA15134@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="QRj9sO5tAVLaXnSD" Content-Disposition: inline In-Reply-To: <20190515103309.GA15134@redhat.com> User-Agent: Mutt/1.11.3 (2019-02-01) Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org --QRj9sO5tAVLaXnSD Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > On Wed, May 15, 2019 at 12:03:44PM +0200, Lorenzo Bianconi wrote: > > > On Wed, May 15, 2019 at 11:43:55AM +0200, Lorenzo Bianconi wrote: > > > > > On Mon, May 13, 2019 at 11:48:37AM +0200, Stanislaw Gruszka wrote: > > > > > > On Mon, May 13, 2019 at 10:41:28AM +0200, Lorenzo Bianconi wrot= e: > > > > > > > > Lorenzo Bianconi writes: > > > > > > > >=20 > > > > > > > > > Introduce a knob in mt7603 debugfs in order to enable/dis= able > > > > > > > > > edcca processing > > > > > > > > > > > > > > > > > > Signed-off-by: Lorenzo Bianconi > > > > > > > >=20 > > > > > > > > It's good to explain what edcca does and how the file is us= ed supposed > > > > > > > > to be used. In other words, have a small introduction for t= he user. > > > > > > >=20 > > > > > > > Hi Kalle, > > > > > > >=20 > > > > > > > edcca is used for adjusting energy detect based on CCA thresh= olds. > > > > > > > The code was already there so I just reported the acronym. > > > > > >=20 > > > > > > What for it is needed ? > > > > >=20 > > > > > Care to comment why EDCCA is needed at all ? > > > > >=20 > > > > > Taking that debugfs file that enable it is read-only, it looks li= ke > > > > > feature that nobody needs nor tests. > > > >=20 > > > > already fixed in v2 > > > > https://patchwork.kernel.org/patch/10940645/ > > >=20 > > > I'm aware of this patch and other one for mt76x02. But so far in the > > > sources EDCCA is disabled for mt76x02 without possibility to enable it > > > (and this permission file issue was pointed by Kalle during review, n= ot > > > by someone who want to test EDCCA). So again, what for EDCCA is neede= d ? > >=20 > > As I have already written in a previous email, ED/CCA is used to contro= l tx power > > according to the CCA MIB counters (e.g do not transmit if the channel b= usy time > > is higher than 90% for given amount of time in a row). I guess it is re= quired > > by ETSI regulatory. > But what is user case for that, i.e. who need this (it wasn't implemented= in > mt76x2 since you added it on Dec 2018). What will happen if it will be re= moved? >=20 > > Regarding file permission for mt76x02 debugfs edcca node is a typo. > Typo or not, effectively disable the feature and show nobody is > testing it. >=20 > The reason I'm asking is that seems EDCCA is the main reason to > implement watchod for mt76x2, it wasn't necessary to have a watchdog > as seems devices did not hung before EDCCA was added. IIRC I added the first watchdog implementation to fix tx hangs that occur under heavy load even using FCC regulatory (so when EDCCA processing is disabled) Regards, Lorenzo >=20 > Stanislaw --QRj9sO5tAVLaXnSD Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iHUEABYIAB0WIQTquNwa3Txd3rGGn7Y6cBh0uS2trAUCXNv0aQAKCRA6cBh0uS2t rPgLAP4w8B/CCKhKYOXh4RQKO/XtaepRDQOjvmwlJK8QodQttgD+Im2Bs4ajKzhp dKHjOt3+RKVPFz7K0/DpxHusXcTI9QA= =xyF2 -----END PGP SIGNATURE----- --QRj9sO5tAVLaXnSD--