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 2EE95C43217 for ; Mon, 11 Oct 2021 10:57:15 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id F170B60C4B for ; Mon, 11 Oct 2021 10:57:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org F170B60C4B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=the-dreams.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Reply-To:Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date :Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=W9fKtNpvUqU7yjW1Wyrr1RYZOB9CPRjIybzEmcVvSSs=; b=PohO4Zb0T+ZV9nwgOX3pL/FLAd BrSxImGYAP8M+nLdlaFj4qmUGdrAmU0/Y+JusiiI+zOyMALSr/IzLST7+dDFy/BHunI9aiw4kki4R FlTW3l/df7zAMrMjA/rUvi4Ht2inV+Oo2g5RYNVpxP2TdDTZWnVBq8wm8jXOhYGVIdGqJmyHxlVh5 /P+yu0917B7nz5tJL1Uzwjd/gJNeYWMfsXaSIfUktf3Oe0MH1wMOCCjMXsQE132EZIxCgqLkHSVIf NhCHi6t5lysjjLTsMVNh7ieBkUdNq49jgy+8Tq0zSfGvhjjlBltTffgsUYNmdsmvQ31auBDbTal8i 6udz4gsg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mZszN-008vyC-4A; Mon, 11 Oct 2021 10:57:01 +0000 Received: from sauhun.de ([88.99.104.3] helo=pokefinder.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1mZsz9-008vuv-40; Mon, 11 Oct 2021 10:56:48 +0000 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 In-Reply-To: <1891acec7f5c417f62081a8b10249b265df7ea62.camel@mediatek.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211011_035647_334812_9FBC8B93 X-CRM114-Status: GOOD ( 10.64 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============7897011480295589297==" Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org --===============7897011480295589297== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="VEgwt+bxKre9p0ta" Content-Disposition: inline --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-- --===============7897011480295589297== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek --===============7897011480295589297==--