summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorMartin Blumenstingl <martin.blumenstingl@googlemail.com>2025-03-29 19:58:55 +0100
committerNeil Armstrong <neil.armstrong@linaro.org>2025-04-22 09:25:47 +0200
commitf254ae62fb155bc75c69fa83711b006f091ab8db (patch)
tree8d0131fcdeeb59ad11708754cbde04e9ce2d43cf
parentfdedfc2109a55ebe408634a8554b91ac8d098052 (diff)
arm64: dts: amlogic: a1: enable UART RX and TX pull up by default
Some boards have noise on the UART RX line when the UART pins are not connected to another device (such as an USB UART adapter). This can be addressed by using a pull up resistor. Not all boards may provide such a pull up resistor on the PCB so enable the SoC's pull-up on the UART RX and TX pads by default. This matches the default (from u-boot or SoC hardware) state for the pinmux configuration on these pads. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org> Link: https://lore.kernel.org/r/20250329185855.854186-8-martin.blumenstingl@googlemail.com Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
-rw-r--r--arch/arm64/boot/dts/amlogic/meson-a1.dtsi1
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/arm64/boot/dts/amlogic/meson-a1.dtsi b/arch/arm64/boot/dts/amlogic/meson-a1.dtsi
index 1eba0afb3fd9..f7f25a10f409 100644
--- a/arch/arm64/boot/dts/amlogic/meson-a1.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-a1.dtsi
@@ -233,6 +233,7 @@
groups = "uart_a_tx",
"uart_a_rx";
function = "uart_a";
+ bias-pull-up;
};
};