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 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 DD2A6C54EBD for ; Mon, 9 Jan 2023 03:55:57 +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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=S4YhmkD/Fuh6LmCT+HC0JHTx4O9dLD4pvprmpYNX9xs=; b=FcCiFLk0/y2EJc +bM3OSZE1Nq/Y0hOLiLJkJ6mp8cgfx2ISjP07Mmzcfso1/E91dCZinhF6ptT70FYRvQe1ZL5oraDL cbvbbmndlw7uYWvwBSueHMviLBB8H/7tJ6W/KLF5Nd4ayE5UpLvGSamNKqQ8uzRilMIlogowrFL5T 2lNQWgJf059q5R/fXtq5WViPDzJHc5u0bSrhgkvPR8fWvSFnoRlHlbEUfOVeF/gjWq16yvbMmnW7A AyPdTh5FMFyc4RxTREUBnFbO7V4qAx/upXjLGC2pEeJILuf7cweNFpZr/oIhSpY+f3+OP6PsBtjML Lbs6VjHXMdRIHcxgiOGA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pEjFV-00HBER-Nv; Mon, 09 Jan 2023 03:55:01 +0000 Received: from dfw.source.kernel.org ([2604:1380:4641:c500::1]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pEjFQ-00HBDF-RC for linux-arm-kernel@lists.infradead.org; Mon, 09 Jan 2023 03:55:00 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 68E7160EF7; Mon, 9 Jan 2023 03:54:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B52D0C433D2; Mon, 9 Jan 2023 03:54:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1673236493; bh=p/XxkV1EJLS7tRjTyqnzIqnXBjpV4nsiH/JLkdkvOXU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GfjCDY3kRIrJp//aIqpUXP1+UAdEhxydeP+qDyOY7GqiHhfMIaWrYSKQLyThskRdd SzS5+bPSUC/dHqzgOGi1EU8/pMDL+Wzx34qiUK9oON4wqMDGPYZzuEXOKnRcsd5Nvn 6w/7b3x8LRa3ghSKMWVNCJhTjhR+bhOd6MyqpbrcsvEmOraLmfSxfvq8tJOdmC+3Vg hSi/JQWJesazYLhGpf89Lrh/OptTpjbuzBXCw8Zl1RI/Z9qiMLRSV23FdJZNBN4nXJ zXmvswZB6z9M9DtLOfJ2t8H++dsDVosfHNN4088yWuYhFGxtenGMQtvFugsTbRK66T xaPCI80pyk3aw== Date: Mon, 9 Jan 2023 11:54:45 +0800 From: Shawn Guo To: Marek Vasut Cc: linux-arm-kernel@lists.infradead.org, Denys Drozdov , Fabio Estevam , Frieder Schrempf , Krzysztof Kozlowski , Li Yang , Marcel Ziswiler , Matthias Schiffer , Max Krummenacher , NXP Linux Team , Peng Fan , Rob Herring , Tim Harvey , devicetree@vger.kernel.org Subject: Re: [PATCH 2/2] arm64: dts: imx8mp: Add support for Data Modul i.MX8M Plus eDM SBC Message-ID: <20230109035444.GA18301@T480> References: <20221218051800.495932-1-marex@denx.de> <20221218051800.495932-2-marex@denx.de> <20230101040036.GU6112@T480> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230108_195456_997424_FC5E7B49 X-CRM114-Status: GOOD ( 19.96 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Jan 05, 2023 at 10:30:17PM +0100, Marek Vasut wrote: > On 1/1/23 05:00, Shawn Guo wrote: > > [...] > > > > + panel: panel { > > > > No compatible? > > The compatible string is filled in by expansion module DT overlay, so no > default compatible string in the panel node here. The panel interface is the > same for all panels that can be atteched to this board, so the panel node is > common for all DTOs and can be in the base DT. > > > > + backlight = <&backlight>; > > > + power-supply = <®_panel_vcc>; > > > + /* Disabled by default, unless display board plugged in. */ > > > + status = "disabled"; > > > + }; > > > + > > > + reg_panel_vcc: regulator-panel-vcc { > > > + compatible = "regulator-fixed"; > > > + pinctrl-names = "default"; > > > + pinctrl-0 = <&pinctrl_panel_vcc_reg>; > > > + regulator-name = "PANEL_VCC"; > > > + regulator-min-microvolt = <5000000>; > > > + regulator-max-microvolt = <5000000>; > > > + gpio = <&gpio3 6 0>; > > > > GPIO_ACTIVE_HIGH? > > No, the 0 is correct and you're not the first one to wonder about this > oddity. I understand that the polarity is ignored by Linux Kernel. But it shouldn't prevent us from describing the polarity cell with defines for better readability. I'm always looking for the pattern below when reviewing the device tree. regulator-xxx { compatible = "regulator-fixed"; ... gpio = <&gpio3 6 GPIO_ACTIVE_HIGH>; enable-active-high; } Or for low polarity: regulator-xxx { compatible = "regulator-fixed"; ... gpio = <&gpio3 6 GPIO_ACTIVE_LOW>; } The polarity define is helpful for me to validate whether `enable-active-high` property should present. Shawn > See drivers/gpio/gpiolib-of.c : > > 203 /* > 204 * The regulator GPIO handles are specified such that the > 205 * presence or absence of "enable-active-high" solely controls > 206 * the polarity of the GPIO line. Any phandle flags must > 207 * be actively ignored. > 208 */ > 209 #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE) > 210 { "regulator-fixed", "gpios", "enable-active-high" }, > 211 { "regulator-fixed", "gpio", "enable-active-high" }, > > [...] _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel