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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B7369C433E2 for ; Thu, 10 Sep 2020 13:00:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DD01206D4 for ; Thu, 10 Sep 2020 13:00:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="Elr96xnz"; dkim=pass (1024-bit key) header.d=amazonses.com header.i=@amazonses.com header.b="Wv3iIPZm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730920AbgIJNAk (ORCPT ); Thu, 10 Sep 2020 09:00:40 -0400 Received: from a27-188.smtp-out.us-west-2.amazonses.com ([54.240.27.188]:49512 "EHLO a27-188.smtp-out.us-west-2.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730909AbgIJM6T (ORCPT ); Thu, 10 Sep 2020 08:58:19 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=zsmsymrwgfyinv5wlfyidntwsjeeldzt; d=codeaurora.org; t=1599742198; h=MIME-Version:Content-Type:Content-Transfer-Encoding:Date:From:To:Cc:Subject:In-Reply-To:References:Message-ID; bh=s775L7iCYKpGMncC/fTv63fok23Pnh/vNT1134dXG/I=; b=Elr96xnzsEBEUVxFkM7+mD6XMQzh9xlVq4Brz8bIKJnMDvSi1h14zCUFkejWeOfW R5SACiNIuAObBH2Pb82/9UAy99TS7GDOfNucN4Z2Euqhv8MST+nzqQBcb1yZ5s9Cieu yzLU6A6PeyNu1POswfM/bDdYqidogQwTXneVxHkg= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/simple; s=hsbnp7p3ensaochzwyq5wwmceodymuwv; d=amazonses.com; t=1599742198; h=MIME-Version:Content-Type:Content-Transfer-Encoding:Date:From:To:Cc:Subject:In-Reply-To:References:Message-ID:Feedback-ID; bh=s775L7iCYKpGMncC/fTv63fok23Pnh/vNT1134dXG/I=; b=Wv3iIPZmLaD1mQJyPljMTQiUJ40ELe5fJ5rkE7TTk/pyGEVNsuHRr8997X2cDNW3 VxFwSm8ikScENv1tYJJ/UnEWPM0hQKxyOcXAtARDo5ZF+H+hdqvKqSRm4Kxulje5q5w rxYqdhdLfUrgb/QP2LSW18r/xKRCcV+uXTapIEdE= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 10 Sep 2020 12:49:58 +0000 From: skakit@codeaurora.org To: Doug Anderson Cc: Bjorn Andersson , Matthias Kaehlcke , Greg Kroah-Hartman , Andy Gross , Rob Herring , linux-arm-msm , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , LKML , Akash Asthana , Roja Rani Yarubandi , msavaliy@qti.qualcomm.com Subject: Re: [PATCH V4 2/4] arm64: dts: qcom: sc7180: Improve the pin config settings for CTS and TX In-Reply-To: References: <1599145498-20707-1-git-send-email-skakit@codeaurora.org> <1599145498-20707-3-git-send-email-skakit@codeaurora.org> Message-ID: <010101747810c24f-a169785b-0866-4932-a24e-80ff53393de2-000000@us-west-2.amazonses.com> X-Sender: skakit@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 X-SES-Outgoing: 2020.09.10-54.240.27.188 Feedback-ID: 1.us-west-2.CZuq2qbDmUIuT3qdvXlRHZZCpfZqZ4GtG9v3VKgRyF0=:AmazonSES Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Doug, On 2020-09-10 02:58, Doug Anderson wrote: > Hi, > > On Thu, Sep 3, 2020 at 8:07 AM satya priya > wrote: >> >> --- a/arch/arm64/boot/dts/qcom/sc7180-idp.dts >> +++ b/arch/arm64/boot/dts/qcom/sc7180-idp.dts >> @@ -474,32 +474,30 @@ >> &qup_uart3_default { >> pinconf-cts { >> /* >> - * Configure a pull-down on 38 (CTS) to match the pull >> of >> - * the Bluetooth module. >> + * Configure no-pull on CTS. As this is driven by BT, >> do not >> + * specify any pull in order to not conflict with BT >> pulls. >> */ >> pins = "gpio38"; >> - bias-pull-down; >> - output-high; > > Weird, how did that output-high sneak in there? Glad it's going away. > > >> + bias-disable; > > I'm not convinced that the removal of the pul is the correct thing > here. Specifically for the rx line the comment makes the argument > that if we power off the Bluetooth module then it will stop driving > this pin. In that case if we remove the pull here then the line will > be floating and that can cause some extra power consumption as the > line floats between different logic levels. Do you really need to > remove this pull? > Okay, will keep the pull-down back for CTS. > Same comment for the next patch where you add the sleep settings. > > > -Doug