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=-2.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, URIBL_BLOCKED,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 B5B58C4360F for ; Tue, 2 Apr 2019 09:01:17 +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 845F52075E for ; Tue, 2 Apr 2019 09:01:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="ttfTAEqP" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 845F52075E 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=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender:Content-Type:Cc: List-Subscribe:List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id: In-Reply-To:MIME-Version:References:Message-ID:Subject: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=93aHZ3ooWAXaHXwz9ZfdkDaG3xEbfbfTdZOhruRj9mI=; b=ttfTAEqPt68sl4THLawlS6rIl md7Yyq0nzWGOdgDg4dmyP0hZkj/0Av7YWVZssa1vY+x/llwQCgizp43lkBQY+lyIUPv26JNACRaPa 47vP8v0dwGnJ++xksis8gngvKrNEzYoj9WFkQB8f82QaT/vbmIGSH3UN5G52/bxNadS/MNPNdhUgl 5000N3mt7B7S3Cw48eRn65mVhK86qGh4SYIUjG6ft0HHLCklUPsYMK/3jEux7LXnDjKMzI/sx8KzA +2tKyjtPFRKa61+TXJXp8nix/V/tQhzXiAYGhkS1BhB1/hRozLJtsYMFkoK1yrKAWzuiDhMeetITO 9vW29+Jvg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hBFI6-0003Q4-4c; Tue, 02 Apr 2019 09:01:10 +0000 Received: from sauhun.de ([88.99.104.3] helo=pokefinder.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hBFI3-0003Ph-0I for linux-arm-kernel@lists.infradead.org; Tue, 02 Apr 2019 09:01:08 +0000 Received: from localhost (p5486CD10.dip0.t-ipconnect.de [84.134.205.16]) by pokefinder.org (Postfix) with ESMTPSA id B43AC2CF606; Tue, 2 Apr 2019 11:01:05 +0200 (CEST) Date: Tue, 2 Apr 2019 11:01:05 +0200 From: Wolfram Sang To: Rayagonda Kokatanur Subject: Re: [PATCH v5 2/8] i2c: iproc: Add slave mode support Message-ID: <20190402090105.GA2960@kunai> References: <20190214175725.60462-1-ray.jui@broadcom.com> <20190214175725.60462-3-ray.jui@broadcom.com> <20190327221452.GA15396@kunai> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190402_020107_194849_C76F6B1D X-CRM114-Status: GOOD ( 11.86 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Shreesha Rajashekar , Rob Herring , Ray Jui , linux-i2c@vger.kernel.org, Michael Cheng , bcm-kernel-feedback-list@broadcom.com, linux-arm-kernel@lists.infradead.org Content-Type: multipart/mixed; boundary="===============2100241728883314873==" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org --===============2100241728883314873== Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="NzB8fVQJ5HfG6fxh" Content-Disposition: inline --NzB8fVQJ5HfG6fxh Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable > > >> + /* RANDOM SLAVE STRETCH time - 20ms*/ > > > > > > What is a "random stretch time"? 20ms sounds like a lot. Also, missing > > > space before comment terminator. > > > > > > > Rayagonda, > > > > Could you please help to comment on the choice of the 20 ms to allow > > clock stretch from the slave? In probably all cases, the slave should > > not need more than 1 ms? 20 ms does seem way too long as Wolfram pointed > > out. >=20 > In fact we are programming max slave stretch time ie 25ms, comment > should be correcting. > Its maximum time for slave to complete read/write operation, if slave > is done with read/write then clock will not be stretched further, it > will be released immediately. Ah, now I see. This is a protection against the slave stretching the clock forever. This makes sense. > Hence I feel no harm in programming max timeout value. I agree. "Random stretch" is just a bit confusing as a name. "Maximum" would have been more clear IMO. --NzB8fVQJ5HfG6fxh Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEEOZGx6rniZ1Gk92RdFA3kzBSgKbYFAlyjJM0ACgkQFA3kzBSg KbYwnRAAhyvKGZin7EPbNl42uih8M22BfSs+//ZzA92ckfe99z34MztaQzSbXRym wKO3ncesoIPM81IrYkwTY4lNTCRCLMxsmXMJbd518lumNp/4ZUp9sNSmoD8Z/61R e6YWJ7kysBz/iNjcbw8igaJLTvrZfV9IeSxuNdxQXCq9k9Whaa1yealO9CVVJiNU TpA16pFWbI7it7SuGwY2EEO/3asBqYj0CjjUthtS8kwqZ67MTVVzoK2cxstaoXec 1T9dhvRX++vIDpBoFlTRQH2ZGpSEQJmKosvNuagNIiKs/6Rcw+AbNLUYx9Z1qRwt FxYADEeszSLtFM1QoqTcwwERDap32YnZzhnnC61fpI+SIIKV6twClJWeZ/gPrU5u 0bxeAN8GwJ5OzxTAnoKNECwSUf0CsN2jnjbMv+1kXKmXJgYEhxQotgdxL2ywXeJ1 RL9SI2xApC47SAX6qJX/Z4ZtxT2aF1hdG7doy3rUu82e2VX9FcVyl/Qn1XQdgE6G h9JR5mqtOA5K9e3bDcKFQgeSFFCM+gKWd4LBfkEpsLR6EIzglwqcAtWYgbfp7kuD PSiacbJCZDTcbHMezQt2GI683MaDcIhwIYSPzgqv8KlHK9TXXHqm/+l3D1+RTrCz +aBK7knHXHplb37AOPZKSbjqCe9ksOJoIFIgAwaJu8rmZUs09X8= =MmnH -----END PGP SIGNATURE----- --NzB8fVQJ5HfG6fxh-- --===============2100241728883314873== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel --===============2100241728883314873==--