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 <a.fatoum@xxxxxxxxxxxxxx>
---
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
>;
};
--
2.39.5
