From patchwork Wed Apr 27 19:20:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Heiner Kallweit X-Patchwork-Id: 567616 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 7A4BBC433EF for ; Wed, 27 Apr 2022 19:22:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232398AbiD0TZw (ORCPT ); Wed, 27 Apr 2022 15:25:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234249AbiD0TZQ (ORCPT ); Wed, 27 Apr 2022 15:25:16 -0400 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0FD6515B8; Wed, 27 Apr 2022 12:20:46 -0700 (PDT) Received: by mail-wr1-x42f.google.com with SMTP id t6so3848434wra.4; Wed, 27 Apr 2022 12:20:46 -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:from:subject:to:cc :content-language:content-transfer-encoding; bh=l+fWRCnlsDX073yEnS2AwNoaDg75F4nU098U70Iwazw=; b=XQ7Tmh35axRFQPHV2QSYPADNzmaPb568O/5D2oDi9Een/DFOirBn1j6CPAcNahRZcS MYBGgi0+DA6aNu0j/7V6pP/goI5jW7ktJgIXN71ofVmFeIdz3fSfNjYZ4LlWGjE4+y8G H8XvyIqEdyQ2pCR4QqSXcvicztmmfnrEExE5mfhed7HIv+xaPMXBnPrvs44ubuUdO5WL yRHG0SL4wCsh2rAcmmI1l40qer4f0Sm1KKodjNaFtYMUt60hSzcdHRfy5bJIRHuHIe/X bwMeZRGe0AE8FSDh6L4+mDZVHKyWEVIz/hVUvUbShU7PumxTCTcGRJi1oINmldVd8Lr0 ZQfQ== 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:from :subject:to:cc:content-language:content-transfer-encoding; bh=l+fWRCnlsDX073yEnS2AwNoaDg75F4nU098U70Iwazw=; b=I2PHlu07BMt5J1b/eVL4+FsC3NxPdR5fMtDkw/TXPPZw8C62pfKgl4Q9NHgQKslJs2 yI63+TiHrt0WlqkJXjZ4P/Ei5+pdtJ2XByysKiMiSUWwtPjsQNEJbFcmGeinlcBK57W4 e17fik3S94XA2MnqaoYt3hKBRHOpMJLKqyIV7ywNx0OZkJGxpsvO1uc/mD5jvKgYLEH5 WRH5xAh5UNfU53QsnvgIWgNyaQ1uOdN93+ai3mnyddzj2IDz/M8DFNrmPK9lnoWNfIMY e7hnShsIlqDz2JhrnHFImb4EKUAAEaoQSElDn36YyVxPtTydYN13n2cAsiPerBXiLEe7 vTIA== X-Gm-Message-State: AOAM530SkXyN0M6I1LEeVzTmAzES2fUY7tj/DtZmvJoO0e5AHnY7i6PJ kMyysm3sK3YbKklEdbNcZt8= X-Google-Smtp-Source: ABdhPJyQuKyD0Ue7NvGpQOg3e2fy2XDG7LhcnSm4XToT4rx/2GyfR4m+gitgPaifyJLYl/9Fp+Awhg== X-Received: by 2002:adf:eb09:0:b0:207:bb77:9abb with SMTP id s9-20020adfeb09000000b00207bb779abbmr23721563wrn.375.1651087245295; Wed, 27 Apr 2022 12:20:45 -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 v18-20020adfc5d2000000b0020589b76704sm16188366wrg.70.2022.04.27.12.20.44 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 27 Apr 2022 12:20:44 -0700 (PDT) Message-ID: <3e6c934e-5298-42c5-c346-31b1acaa06ba@gmail.com> Date: Wed, 27 Apr 2022 21:20:40 +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 From: Heiner Kallweit Subject: [PATCH v2 0/3] i2c: gpio: support write-only sda To: Rob Herring , Krzysztof Kozlowski , Wolfram Sang , Wolfram Sang Cc: "linux-i2c@vger.kernel.org" , "devicetree@vger.kernel.org" Content-Language: en-US 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. This patch makes i2c-gpio usable with such devices, based on new DT property i2c-gpio,sda-output-only. v2: - improve commit message for patch 1 Heiner Kallweit (3): dt-bindings: i2c-gpio: Add property i2c-gpio,sda-output-only i2c: algo: bit: allow getsda to be NULL i2c: gpio: support write-only sda .../devicetree/bindings/i2c/i2c-gpio.yaml | 4 ++++ drivers/i2c/algos/i2c-algo-bit.c | 16 +++++++++++++--- drivers/i2c/busses/i2c-gpio.c | 14 +++++++++++--- include/linux/platform_data/i2c-gpio.h | 2 ++ 4 files changed, 30 insertions(+), 6 deletions(-)