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=-7.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 BE1A8C43461 for ; Thu, 3 Sep 2020 15:09:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9A66720716 for ; Thu, 3 Sep 2020 15:09:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="L8mP/a6I" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729357AbgICPJh (ORCPT ); Thu, 3 Sep 2020 11:09:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728999AbgICN6P (ORCPT ); Thu, 3 Sep 2020 09:58:15 -0400 Received: from mail-lj1-x241.google.com (mail-lj1-x241.google.com [IPv6:2a00:1450:4864:20::241]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CB295C061A1D; Thu, 3 Sep 2020 06:47:13 -0700 (PDT) Received: by mail-lj1-x241.google.com with SMTP id t7so3069865ljo.13; Thu, 03 Sep 2020 06:47:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=k3qzuThp72U/KRxwqVBmH8skw7M3iKBLI2uUGRnjLys=; b=L8mP/a6IrjsOnBUJNLH9gtRvDP+4OMbHI+ZwhcrchPmprm1bWwSXCF3qdpZNSLZitr 5vxo1+pmmZE4aqpsEmb9R44gchROZJsr06CkDcuqrYl2QZJuhGs2QZpQ3dhuJkfnkkyp drHo4YDPArnj1+J49nUababBHTtwnFLT0B5m//G0fxwxB/gKJHtQtLIKtgs4CbdZfkge SO1qNNzSOsZLrGVzu2UB6UkuJ/emvvSSx0zcPF5cLIJjv9LQlc5q34Erkx5cL3E46lZU i+hpfnP8g/Nm4s66rEd5vhzeG+kMEWSztvvit157Lw7hGQBHSK7WWoyKqlgwaSSEWCDf fqhg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=k3qzuThp72U/KRxwqVBmH8skw7M3iKBLI2uUGRnjLys=; b=jwBk7gYLNiMAxzl0VacAbMtAjdcKiNqnbStDTWbvhkxd10FwezL1DXN0WTecIW/9hO b+18eKz1c0EvzTrr6b1xhqVM7+bBm1LnDlLirseu48WS4nMVRPI5Ei2cHRXLt0Y41q9m VnkGFnCvkG1JMHWgiavaNVCBWT6ofLZeSrfG4kewL7pKmlBECtLy5XfI8I0Ww6r8Ol3J XWoVROlFrTg0+iY2yNLfnbCqYCO04kVe+ZQ04kuMqZ7IdyA0okUdljaPBiaQx6eYc07B LrnxwjNhHOht5xGxBFMTLHjbKzhozeMYry3vBAi1SrTrJ4t1d6Fu4F5HYpUgFF48Ww9Z mh2g== X-Gm-Message-State: AOAM532tFxt1LQufFJk+tHhE0suHQBsciM15Lw/2Vce1VNrvirhAIw7T VCrYWC50LHKiTR531Wri0Mg= X-Google-Smtp-Source: ABdhPJy8eL2bmmPblOvXEyLk1+3kYW10KFUyH34uTWW02OusL+7ojvhtmrJ/zedSljYSdLAXGPWwGg== X-Received: by 2002:a2e:574c:: with SMTP id r12mr1398000ljd.302.1599140832286; Thu, 03 Sep 2020 06:47:12 -0700 (PDT) Received: from [192.168.2.145] (109-252-170-211.dynamic.spd-mgts.ru. [109.252.170.211]) by smtp.googlemail.com with ESMTPSA id k12sm614296ljh.95.2020.09.03.06.47.11 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 03 Sep 2020 06:47:11 -0700 (PDT) Subject: Re: [PATCH v3 05/22] i2c: tegra: Use reset_control_reset() To: Andy Shevchenko Cc: Thierry Reding , Jonathan Hunter , Laxman Dewangan , Wolfram Sang , =?UTF-8?B?TWljaGHFgiBNaXJvc8WCYXc=?= , linux-i2c , linux-tegra@vger.kernel.org, Linux Kernel Mailing List , Peter De Schrijver References: <20200903005300.7894-1-digetx@gmail.com> <20200903005300.7894-6-digetx@gmail.com> From: Dmitry Osipenko Message-ID: <07e418bb-77c1-a3bc-bb8b-b930b8c723df@gmail.com> Date: Thu, 3 Sep 2020 16:47:10 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-tegra-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org 03.09.2020 14:11, Andy Shevchenko пишет: > On Thu, Sep 3, 2020 at 3:53 AM Dmitry Osipenko wrote: >> >> Use a single reset_control_reset() instead of assert/deasset couple in >> order to make code cleaner a tad. > >> Note that the reset_control_reset() >> uses 1 microsecond delay instead of 2 that was used previously, but this >> shouldn't matter. > > What datasheet says about this delay? The public datasheet doesn't say anything specific about the I2C controller reset time. IIUC, controller logic runs at 200/400 MHz, so 1us should be enough for the reset. I'm sure that somebody from NVIDIA should know the exact answer and will correct me if I'm wrong. I CC'd Peter De Schrijver who is a maintainer of the Tegra's clock-and-reset driver.