From patchwork Wed Apr 27 19:23:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiner Kallweit X-Patchwork-Id: 567615 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B494CC4321E for ; Wed, 27 Apr 2022 19:27:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232516AbiD0TaV (ORCPT ); Wed, 27 Apr 2022 15:30:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32972 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233876AbiD0T3A (ORCPT ); Wed, 27 Apr 2022 15:29:00 -0400 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F046C4ECF2; Wed, 27 Apr 2022 12:25:18 -0700 (PDT) Received: by mail-wr1-x42a.google.com with SMTP id d5so3859990wrb.6; Wed, 27 Apr 2022 12:25:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language :from:to:cc:references:in-reply-to:content-transfer-encoding; bh=0W3gP71n1MpZQMJz0XuN2Q/9yyGOAs5p7ZQydj5TXzM=; b=IopDI538q2NMk/iwKb7awj5KfPdKiaM1XdpuM9nkHAkyvoji6a83CyYMnOnB68MYpN Ut50K3HFUOgy3rCVTGq+yZGRUMUzPY/HHa8GAThXKVnFdQU82ZT9NtHh2LOVHPZs8dP+ yxLEeillobzoDqW/KJkhTOEQV52p7QcqN+/xXZz+ekIC+u7RNOAcwL9kQV3WEg3+vHPR WhOwr/NlYCOyrCY6LXssKZsIA4T/DwUUJEx80UiuIFoja5EMNP2XrEhAdNOOyS8BFrSG 0/qT20j3hA6TizkAgAUwc9SjWi5gr9jcqA5kEL+bznCRKIkEKdf8TUXbFvOAoO5w2Zu5 eZaQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:from:to:cc:references:in-reply-to :content-transfer-encoding; bh=0W3gP71n1MpZQMJz0XuN2Q/9yyGOAs5p7ZQydj5TXzM=; b=Fi3Oj5/iQzn43cINgBPf0Jcc+n8HOsEHriAskmHqynk+JSpiN4U19ldXKcJh7l2Vgp Vslakm/WbHEwvNfYbbfk2Ki68D86OLMM+wYZf9jSu/DcalTkHMhf4iEpxzLT6deOZCFT D6xpFsoLkUFsTCE7ar+qCsQaHNX0Pjb3+7QftIyIjmn1uNSEgkvJXdfaHxMxydb2WezP H/WgfxLf7Xax3ccW33j4d1KbSyrkTRjFv+88+r5QRqLyKSUtLSkWH780xdvwX1C0bEu8 HnLdCsjCrh5JslOUWN0VcTziNQwXKNOntiZH3W7tR+xVo19XJLf0DjVHbBBEWn3f+dQx +Sog== X-Gm-Message-State: AOAM5316jojx9vn8JsRa8hFGTbcANXMegwDc8xmYEbfuVHq0ttqTVbPm FY6eLmjwhdNc8asqQziQTW9tqK1wjG8= X-Google-Smtp-Source: ABdhPJxlQSR42melvpN8JuJWA3iGQzH2dKFKRtRFwARgPNEKySFm88SLBQBfG2iWXu5+dJel1mP9wg== X-Received: by 2002:a5d:6e87:0:b0:20a:c40a:cda4 with SMTP id k7-20020a5d6e87000000b0020ac40acda4mr23215366wrz.370.1651087516222; Wed, 27 Apr 2022 12:25:16 -0700 (PDT) Received: from ?IPV6:2a01:c23:c002:fc00:393a:1fdf:a518:6420? (dynamic-2a01-0c23-c002-fc00-393a-1fdf-a518-6420.c23.pool.telefonica.de. [2a01:c23:c002:fc00:393a:1fdf:a518:6420]) by smtp.googlemail.com with ESMTPSA id p3-20020adfaa03000000b00207a1db96cfsm15067055wrd.71.2022.04.27.12.25.15 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 27 Apr 2022 12:25:15 -0700 (PDT) Message-ID: Date: Wed, 27 Apr 2022 21:23:28 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: [PATCH v2 1/3] dt-bindings: i2c-gpio: Add property i2c-gpio,sda-output-only Content-Language: en-US From: Heiner Kallweit To: Rob Herring , Krzysztof Kozlowski , Wolfram Sang , Wolfram Sang Cc: "linux-i2c@vger.kernel.org" , "devicetree@vger.kernel.org" References: <3e6c934e-5298-42c5-c346-31b1acaa06ba@gmail.com> In-Reply-To: <3e6c934e-5298-42c5-c346-31b1acaa06ba@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org There are slave devices that understand I2C but have read-only SDA and SCL. Examples are FD650 7-segment LED controller and its derivatives. Typical board designs don't even have a pull-up for both pins. Therefore don't enforce open-drain if SDA and SCL both are unidirectional. This patch makes i2c-gpio usable with such devices, based on new DT property i2c-gpio,sda-output-only. Signed-off-by: Heiner Kallweit Reviewed-by: Rob Herring --- v2: - improve commit message --- Documentation/devicetree/bindings/i2c/i2c-gpio.yaml | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/Documentation/devicetree/bindings/i2c/i2c-gpio.yaml b/Documentation/devicetree/bindings/i2c/i2c-gpio.yaml index fd0402845..25cd1b260 100644 --- a/Documentation/devicetree/bindings/i2c/i2c-gpio.yaml +++ b/Documentation/devicetree/bindings/i2c/i2c-gpio.yaml @@ -33,6 +33,10 @@ properties: open drain. maxItems: 1 + i2c-gpio,sda-output-only: + description: sda as output only + type: boolean + i2c-gpio,scl-output-only: description: scl as output only type: boolean