From patchwork Thu Dec 19 07:25:31 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ahmad Fatoum X-Patchwork-Id: 13914606 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 8B154E77184 for ; Thu, 19 Dec 2024 07:30:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VP0+g6S62LhM6b8BLIcvO/05qFcoS1b6FFLnLooGfMM=; b=wv4xOp4mca/eBZrvTLffniUNRD A6KwlZ6GMYYGhGSxUGiOPNCt/RqAucFDlW0herIh3cjrp0Snub8mc9l6cm/Zl9Fb14IRUPeRCH47X dFpUscnhyXRGejF8wYJ+buceYSDkMFtXp8/s2Lt/vkP1cbe6GWk0O22C4RG0kSoQvxKr8VhqtxMYs uv1QXHxj+yO/Ueww5laylhvICGGrf/nRkuI4MkWvZQcBkFPGUPtp2fwK/WDnFEUkntq/3whxr9NxS 2fbhliGSXwTfV+qULdkoDVNBiBtNXRmHmx3h3lC9Dl2tCAc70b8iZg/8KAs10Oi71EQR7y8Ee3gHZ h9I2dAHQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tOAz0-000000015fq-2qv4; Thu, 19 Dec 2024 07:30:06 +0000 Received: from metis.whiteo.stw.pengutronix.de ([2a0a:edc0:2:b01:1d::104]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tOAum-000000014nl-0Kpl for linux-arm-kernel@lists.infradead.org; Thu, 19 Dec 2024 07:25:45 +0000 Received: from drehscheibe.grey.stw.pengutronix.de ([2a0a:edc0:0:c01:1d::a2]) by metis.whiteo.stw.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1tOAuc-00064O-1t; Thu, 19 Dec 2024 08:25:34 +0100 Received: from dude05.red.stw.pengutronix.de ([2a0a:edc0:0:1101:1d::54]) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1tOAua-004AOG-2u; Thu, 19 Dec 2024 08:25:33 +0100 Received: from localhost ([::1] helo=dude05.red.stw.pengutronix.de) by dude05.red.stw.pengutronix.de with esmtp (Exim 4.96) (envelope-from ) id 1tOAub-00GenW-1k; Thu, 19 Dec 2024 08:25:33 +0100 From: Ahmad Fatoum Date: Thu, 19 Dec 2024 08:25:31 +0100 Subject: [PATCH 07/10] arm64: dts: imx8mp-skov: configure uart1 for RS485 MIME-Version: 1.0 Message-Id: <20241219-skov-dt-updates-v1-7-38bf80dc22df@pengutronix.de> References: <20241219-skov-dt-updates-v1-0-38bf80dc22df@pengutronix.de> In-Reply-To: <20241219-skov-dt-updates-v1-0-38bf80dc22df@pengutronix.de> To: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Shawn Guo , Sascha Hauer , Pengutronix Kernel Team , Fabio Estevam , Oleksij Rempel Cc: devicetree@vger.kernel.org, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de, Ahmad Fatoum X-Mailer: b4 0.13-dev X-SA-Exim-Connect-IP: 2a0a:edc0:0:c01:1d::a2 X-SA-Exim-Mail-From: a.fatoum@pengutronix.de X-SA-Exim-Scanned: No (on metis.whiteo.stw.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-arm-kernel@lists.infradead.org X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241218_232544_118373_3BCBDCE5 X-CRM114-Status: GOOD ( 11.81 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org uart1 TX, RX and RTS signals go off the base board and to a RS485 transceiver. Describe this in the device tree. Signed-off-by: Ahmad Fatoum --- arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi b/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi index 7ae686d37dda..bce23d62cd27 100644 --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi @@ -404,6 +404,13 @@ &uart1 { pinctrl-names = "default"; pinctrl-0 = <&pinctrl_uart1>; status = "okay"; + /* + * While there is no CTS line, the property "uart-has-rtscts" is still + * the right thing to do to enable the UART to do RS485. In RS485-Mode + * CTS isn't used anyhow and there is no dedicated property + * "uart-has-rts-but-no-cts". + */ + uart-has-rtscts; }; &uart2 { @@ -618,6 +625,8 @@ pinctrl_uart1: uart1grp { MX8MP_IOMUXC_UART1_RXD__UART1_DCE_RX 0x140 MX8MP_IOMUXC_UART1_TXD__UART1_DCE_TX 0x140 MX8MP_IOMUXC_UART3_RXD__UART1_DTE_RTS 0x140 + /* CTS pin is not connected, but needed as workaround */ + MX8MP_IOMUXC_UART3_TXD__UART1_DTE_CTS 0x140 >; };