From: Ahmad Fatoum Date: Mon, 6 Jan 2025 16:06:42 +0000 (+0100) Subject: arm64: dts: imx8mp-skov: configure uart1 for RS485 X-Git-Tag: next-20250219~135^2^2~21 X-Git-Url: https://gentwo.org/gitweb/?a=commitdiff_plain;h=5511ebc8da772c019a20563c44e2aff1d62acfa9;p=linux%2F.git arm64: dts: imx8mp-skov: configure uart1 for RS485 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 Signed-off-by: Shawn Guo --- diff --git a/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi b/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi index 5e3a7c859c66..c65fbadd5db3 100644 --- a/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi +++ b/arch/arm64/boot/dts/freescale/imx8mp-skov-reva.dtsi @@ -403,6 +403,13 @@ &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 { @@ -616,6 +623,8 @@ 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 >; };