From patchwork Wed Oct 19 14:01:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amjad Ouled-Ameur X-Patchwork-Id: 13011808 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id DECDFC4332F for ; Wed, 19 Oct 2022 14:03:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:Cc:To:Message-Id:Date:From:MIME-Version :Subject:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=oSspGKo7ZMWPzDvNQqjbPzHGugKS6MK5LCwtccpeYj8=; b=YetsApcFaJy/qj ZGqhvAsJ1XaWkoeJa6lRW4gyhJD3swy+KWCspUIMEFUBTy07ZxYv9EHX9lP0PGzuBB+LrusUSpAXy 5klGaz+8ZXcsqE+HzpzpEZyiLqviWi4GFXU94ZVpJdQHgqTnGCzwODs+FCd5FAh64IgdRHqIEOYru bWrsxuZXwO4nbpj2XwJiyMLPvlAKnGo4BE0Lao63N2GOkNEG/D6uzLyVPrOKm0aV/ewhxoVSWOeNF 4NdsImKKEjaNSGBME4BPcM6bRrl5APGb2fMljKCK5rp0Vh7D1zV1k6vFlNRQshKacNYJHKNqnoMXq 5MmnhXfvjuRI/YUL5usw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1ol9fT-002V03-2k; Wed, 19 Oct 2022 14:03:35 +0000 Received: from mail-wm1-x331.google.com ([2a00:1450:4864:20::331]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1ol9fE-002UiV-UG for linux-amlogic@lists.infradead.org; Wed, 19 Oct 2022 14:03:25 +0000 Received: by mail-wm1-x331.google.com with SMTP id t4so12969738wmj.5 for ; Wed, 19 Oct 2022 07:03:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20210112.gappssmtp.com; s=20210112; h=cc:to:message-id:date:from:content-transfer-encoding:mime-version :subject:from:to:cc:subject:date:message-id:reply-to; bh=PVj2DAdfLIU/pX3XZE26BCq9oqHkdH2P1yACg55ATYc=; b=QlA9FYPVLD1k0zfaUSwjLI8Q83sBFeoAzC7eQuA8Vn4Dp8rjm78gQg6ZSYljWFaYI7 +EDL8mVklujMsDG8GH9sEfGXq2u99dWf+2LcmapexNQMysE0Gk9TzJ7RJR9XciOpt60T v2f7F0XsTAOUDv9oH+0tpL/amAfarJmdENSkKa5Fmhky74UWZjAH3KB+l6inFESY5V1f aNjyQ0JZwMql16HhSJGSg149q426+rWzciTmWU7Ja794brJrFd4gv8Mq63R3zu2Skj0B bJKMfYLkoBFcz8AsXb9NzPVITJMOIhiV15K+OlEVdt/gbPnIOGmsPEGVwyHC61oOIOBn bN5g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:message-id:date:from:content-transfer-encoding:mime-version :subject:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=PVj2DAdfLIU/pX3XZE26BCq9oqHkdH2P1yACg55ATYc=; b=aiJP1xAPoCB2aEo+fksYsfFC11qICZdgOkS9VgHxysMv8MYI3CGSQqTzNF2XjZQfMS blIv1HZJnRJhCCIS8c6v2yqbCzcTD+h7NywHwANvgSagCM2iaWsTBDNZMk1hAWShhfS4 PoGpNL7YcqgYjGIMkIl+4pnceyphj/1Kn9kgK+EsH0/US0vaiNeu0H3nMiZVFH9ll/Wo i8rRgACJVSVXca1cTmNlVhNmpSVwvv4QRYQn43qr4hf7oJuyEXQ0utLTBK9GUBasLEFV TrK7+Bd9WWS74GY9hXeUdRQXFsoTtffj9gMWvtETE7mCzYVBI1oA8fMNhlK2Ga4zAwqk EkUQ== X-Gm-Message-State: ACrzQf3KIsqMPXoMy9bWm4GVvkpOMExkiglqLmiWbWFlX/P45cbtR8Hu dPTPvA92P/sAhPGoN7Q7gFglcA== X-Google-Smtp-Source: AMsMyM5VncASy5bf6AEIZVI0iOwpTrGuyy+Dcp8M8CChiqgXYaA84TGEqw0ITPNidhlKL1DMQ9mdMg== X-Received: by 2002:a05:600c:468f:b0:3c6:f85c:25a1 with SMTP id p15-20020a05600c468f00b003c6f85c25a1mr5696138wmo.60.1666188197604; Wed, 19 Oct 2022 07:03:17 -0700 (PDT) Received: from [127.0.1.1] (rtr.23.90.200.126.unyc.it. [23.90.200.126]) by smtp.googlemail.com with ESMTPSA id o5-20020a5d62c5000000b00228cbac7a25sm13998628wrv.64.2022.10.19.07.03.16 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 19 Oct 2022 07:03:17 -0700 (PDT) Subject: [PATCH v3 0/2] spi: amlogic: meson-spicc: Use pinctrl to drive CLK line when idle MIME-Version: 1.0 X-b4-tracking: H4sIAB4DUGMC/3WNzQrCMBCEX6Xs2ZV0q/bn5HuIh01c7UKalsQWS+m7G7x7Gr6Bb2aDJFElQVdsEG XRpGPIUB0KcD2Hl6A+MgMZotKYE84T8uDxqR9Mk6Ija2upG7mYCrJkOQnayMH1WQuz97nsNb3HuP5O Fspx+7u3EBqspGFpSy5bOl8tr15tlKMbB7jv+/4FlmtKQLQAAAA= From: Amjad Ouled-Ameur Date: Wed, 19 Oct 2022 16:01:02 +0200 Message-Id: <20221004-up-aml-fix-spi-v3-0-89de126fd163@baylibre.com> To: Mark Brown , Neil Armstrong , Krzysztof Kozlowski , Jerome Brunet , Martin Blumenstingl , Kevin Hilman , Rob Herring Cc: Da Xue , linux-arm-kernel@lists.infradead.org, devicetree@vger.kernel.org, linux-amlogic@lists.infradead.org, Neil Armstrong , linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org, Amjad Ouled-Ameur X-Mailer: b4 0.10.1 X-Developer-Signature: v=1; a=ed25519-sha256; t=1666188196; l=1508; i=aouledameur@baylibre.com; s=20220920; h=from:subject:message-id; bh=/olsUtwOJnRswdLM6doMxbVMNoGB8qZCnkiNegDbh1w=; b=aFPV+HsjpwaTDlj7ngssvgjXRK+U0pQ5Yu0g/7m9QFR2MBhDYQYr2iRBsvSx6x+PD6M/5IKDkRss MTCh+avjCw3BKpkSwtHHwbLoGKJbXu2qDxoOXZfjOz5/8jYPCtQC X-Developer-Key: i=aouledameur@baylibre.com; a=ed25519; pk=HgYWawSL4qLGPx+RzJ+Cuu+V8Pi/KQnDDm1wjWPMOFE= X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221019_070321_259220_648277C9 X-CRM114-Status: GOOD ( 12.06 ) X-BeenThere: linux-amlogic@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-amlogic" Errors-To: linux-amlogic-bounces+linux-amlogic=archiver.kernel.org@lists.infradead.org Between SPI transactions, all SPI pins are in HiZ state. When using the SS signal from the SPICC controller it's not an issue because when the transaction resumes all pins come back to the right state at the same time as SS. The problem is when we use CS as a GPIO. In fact, between the GPIO CS state change and SPI pins state change from idle, you can have a missing or spurious clock transition. Set a bias on the clock depending on the clock polarity requested before CS goes active, by passing a special "idle-low" and "idle-high" pinctrl state and setting the right state at a start of a message. Signed-off-by: Amjad Ouled-Ameur --- Changes in v3: - Fixed documentation by removing pinctrl states as they are not mandatory. - Link to v2: https://lore.kernel.org/r/20221004-up-aml-fix-spi-v2-0-3e8ae91a1925@baylibre.com --- Amjad Ouled-Ameur (2): spi: dt-bindings: amlogic, meson-gx-spicc: Add pinctrl names for SPI signal states spi: meson-spicc: Use pinctrl to drive CLK line when idle .../bindings/spi/amlogic,meson-gx-spicc.yaml | 67 ++++++++++++++-------- arch/arm64/boot/dts/amlogic/meson-gxl.dtsi | 14 +++++ drivers/spi/spi-meson-spicc.c | 39 ++++++++++++- 3 files changed, 94 insertions(+), 26 deletions(-) --- base-commit: aae703b02f92bde9264366c545e87cec451de471 change-id: 20221004-up-aml-fix-spi-c2bb7e78e603 Best regards,