From patchwork Wed May 24 03:42:36 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fei Shao X-Patchwork-Id: 685515 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 2BD17C7EE2D for ; Wed, 24 May 2023 03:45:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239337AbjEXDpS (ORCPT ); Tue, 23 May 2023 23:45:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53606 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239330AbjEXDpR (ORCPT ); Tue, 23 May 2023 23:45:17 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3916DE8 for ; Tue, 23 May 2023 20:45:16 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id d2e1a72fcca58-64d5b4c400fso366007b3a.1 for ; Tue, 23 May 2023 20:45:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; t=1684899915; x=1687491915; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=0ynAa7x9o82bh71ClmeyjXXrZJrP7PlGAXE4hWpq/+Q=; b=KvLMYd02H/jW6tjlV8NoTqU4pYbvpat83NrsuNc3YgzZq3DDElxACzaVQSRh3twWDb CrKE4tFWnxzp2Fs/XWRNHJiY6Qf49eRaPSF2YsQcYiTR6vHJs9Nj+eO9SYJ0srunNdwF pSTslBDyq73t+QYu8PRMSH+gpscB5Vxsto2Mk= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684899915; x=1687491915; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=0ynAa7x9o82bh71ClmeyjXXrZJrP7PlGAXE4hWpq/+Q=; b=We3KHpnPyTKYGuE3IGKyKdGspqEXx+Ux6q6i12WB6xwfkSnLAxSkD1teF674stakob xcuM7EubrMcrqEdr+XYUBJd29i86+8xvgILPsg7MFLsrdttWE76IiqWHpEhXSpp/jpWH Y2uU/k964wOXfjWqowfTiomYmZ/L5M3xM5+S87m3vJ7c3vdNvLag4ps7S/O2DoabRiRk DVR1nTYttAp5u1u24htTOGgPhEF1ubhwsFK2RMedWOSicm/6SDme9pSc6upWroEVApKV 2fRtkWVCBGhakdTKu6f88IAb5Tu572BO9nDZI0c6LEIcRwnN/ixePEZMaREonMVWGWVS MAIw== X-Gm-Message-State: AC+VfDwufcuR/SvD5D7m2gMU8w0W3Io+k7DRkxP06HIZRCHYFkqMQ+7s yQ9l9EzCX6fX4mnl9IwIhRxV1Q== X-Google-Smtp-Source: ACHHUZ6FmsJRXxQpJff/TvMGJX03UiNyLftE56b7BjDYgHZnuGgyNrJT+QFH+jWJzdgkGZhEC1c99w== X-Received: by 2002:a05:6a00:23c8:b0:62a:d752:acc5 with SMTP id g8-20020a056a0023c800b0062ad752acc5mr1573806pfc.32.1684899915747; Tue, 23 May 2023 20:45:15 -0700 (PDT) Received: from fshao-p620.tpe.corp.google.com ([2401:fa00:1:10:3b18:4c0c:a178:5536]) by smtp.gmail.com with ESMTPSA id d3-20020aa78683000000b0064cb1fe7e44sm6357616pfo.219.2023.05.23.20.45.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 May 2023 20:45:15 -0700 (PDT) From: Fei Shao To: Jiri Kosina Cc: Rob Herring , Matthias Brugger , Jeff LaBundy , Douglas Anderson , Fei Shao , Rob Herring , Conor Dooley , Dmitry Torokhov , Krzysztof Kozlowski , devicetree@vger.kernel.org, linux-input@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH RESEND v4 1/2] dt-bindings: input: goodix: Add "goodix,no-reset-during-suspend" property Date: Wed, 24 May 2023 11:42:36 +0800 Message-ID: <20230524114233.RESEND.v4.1.Idaa807e609fb3c322b96209c50f71d260917c7be@changeid> X-Mailer: git-send-email 2.40.1.698.g37aff9b760-goog In-Reply-To: <20230524114233.RESEND.v4.2.I424e840ae6de3cdbd67394cf4efd24534f6434ba@changeid> References: <20230524114233.RESEND.v4.2.I424e840ae6de3cdbd67394cf4efd24534f6434ba@changeid> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org We observed that on Chromebook device Steelix, if Goodix GT7375P touchscreen is powered in suspend (because, for example, it connects to an always-on regulator) and with the reset GPIO asserted, it will introduce about 14mW power leakage. To address that, we add this property to skip reset during suspend. If it's set, the driver will stop asserting the reset GPIO during power-down. Refer to the comments in the driver for details. Signed-off-by: Fei Shao Suggested-by: Jeff LaBundy Reviewed-by: Douglas Anderson Reviewed-by: Matthias Brugger Reviewed-by: Jeff LaBundy Acked-by: Rob Herring --- Changes in v4: - Rebase on top of next-20230523 - Collect the review tags Changes in v2: - Use a more accurate property name and with "goodix," prefix .../devicetree/bindings/input/goodix,gt7375p.yaml | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/Documentation/devicetree/bindings/input/goodix,gt7375p.yaml b/Documentation/devicetree/bindings/input/goodix,gt7375p.yaml index ce18d7dadae2..1edad1da1196 100644 --- a/Documentation/devicetree/bindings/input/goodix,gt7375p.yaml +++ b/Documentation/devicetree/bindings/input/goodix,gt7375p.yaml @@ -43,6 +43,15 @@ properties: itself as long as it allows the main board to make signals compatible with what the touchscreen is expecting for its IO rails. + goodix,no-reset-during-suspend: + description: + Set this to true to enforce the driver to not assert the reset GPIO + during suspend. + Due to potential touchscreen hardware flaw, back-powering could happen in + suspend if the power supply is on and with active-low reset GPIO asserted. + This property is used to avoid the back-powering issue. + type: boolean + required: - compatible - reg