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 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id F257BC433FE for ; Mon, 11 Oct 2021 10:56:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E2EE361058 for ; Mon, 11 Oct 2021 10:56:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236082AbhJKK6y (ORCPT ); Mon, 11 Oct 2021 06:58:54 -0400 Received: from sauhun.de ([88.99.104.3]:53570 "EHLO pokefinder.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236190AbhJKK6t (ORCPT ); Mon, 11 Oct 2021 06:58:49 -0400 Received: from localhost (p54b3315a.dip0.t-ipconnect.de [84.179.49.90]) by pokefinder.org (Postfix) with ESMTPSA id 45CB42C00A6; Mon, 11 Oct 2021 12:56:46 +0200 (CEST) Date: Mon, 11 Oct 2021 12:56:45 +0200 From: Wolfram Sang To: Kewei Xu Cc: matthias.bgg@gmail.com, robh+dt@kernel.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, srv_heupstream@mediatek.com, leilk.liu@mediatek.com, qii.wang@mediatek.com, liguo.zhang@mediatek.com, caiyu.chen@mediatek.com, ot_daolong.zhu@mediatek.com, yuhan.wei@mediatek.com Subject: Re: [PATCH v7 6/7] i2c: mediatek: Isolate speed setting via dts for special devices Message-ID: Mail-Followup-To: Wolfram Sang , Kewei Xu , matthias.bgg@gmail.com, robh+dt@kernel.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mediatek@lists.infradead.org, srv_heupstream@mediatek.com, leilk.liu@mediatek.com, qii.wang@mediatek.com, liguo.zhang@mediatek.com, caiyu.chen@mediatek.com, ot_daolong.zhu@mediatek.com, yuhan.wei@mediatek.com References: <20210917101416.20760-1-kewei.xu@mediatek.com> <20210917101416.20760-7-kewei.xu@mediatek.com> <1891acec7f5c417f62081a8b10249b265df7ea62.camel@mediatek.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="VEgwt+bxKre9p0ta" Content-Disposition: inline In-Reply-To: <1891acec7f5c417f62081a8b10249b265df7ea62.camel@mediatek.com> Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org --VEgwt+bxKre9p0ta Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi, > stretching. But if the slave device stretch the SCL line for too long > time, our design still cannot make tSU,STA/tHD,STA/tSU,STO meet spec. Isn't the new algorithm broken if it cannot support clock stretching? What was the problem of the old algorithm not meeting the spec? > However in the old (default) timing algorithm before the commit > be5ce0e97cc7 ("i2c: mediatek: Add i2c ac-timing adjust support"), > tSU,STA/tHD,STA/tSU,STO can meet spec. So we want to define a new > setting "default-adjust-timing" for using the old (default) timing > algorithm." What I still do not get: the old algorithm was able to handle clock stretching. Why can't you update the new one to handle clock stretching as well. I might be missing something, but what is it? Happy hacking, Wolfram --VEgwt+bxKre9p0ta Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAmFkGG0ACgkQFA3kzBSg KbZD3g//RihGqp/HqgzrerO26mwuF/kpOwfbJAoegQU0RTv+6k2GV/0x7lvxfxmj hTRoxrNH+wQYSQLiAwwqPwJ+nXTzoob2WVFXd0+KPeVXm7C84+PIWEg5xth9kpfX Kd+ReQezeCfSEthKN43pE0roJmobGBVK43PX2kxRjluZqN4NbmnaaWoV3xY6YJs0 RWM5gOESUyfAUr1s23uPXPI/+VwA27jpEXhabP5CxciQpJizJ4Agdtx9dkOZuCMF TsgXrFj3ZD6EETIQXoNkTkjZyiSVVC5XyAdKVsGxHA966Vi+s9MCbqPZj9Hq1STO v03VnlbCyQzL2cy/09XYDS8Mu0Xph1MQg8nbQEsD8SgsrR6BM7Lv6gRbXd//TaSH xMz/+kU6B90pBnc+H+wjpwwjMxGTTcwLzRqYB0HsSJ7/kO3vHrXIVe9KyUrRmyHm fHwKAkO0SNKjWyrLdhixR9pmgYTKpVKt4zwmEZiqTvbb923yZ9fU1qpnts7rtXZi P8g5CaqtG2piS/5VLfRjinMbPH6Tl4KPT4OBMZAuoZ10EL16XjdODrrG6jA1oA5h QzWdk8sbQiidCpZG/WGTz9yMQUlZeJZOefsfNyQwOJ5E0kxff+tWFLmF32fusrhm Yoyg00b+KULq1E8zb7X9PCn0o0K8bwE3bhrlGdsHcpCR76p2r6E= =1ToD -----END PGP SIGNATURE----- --VEgwt+bxKre9p0ta--