If the serial tx/rx are floating, it can happen that bogus characters
are detected on the line at boot time. This leads to U-boot accidentally
thinking someone pressed a key to stop autoboot, thus stopping booting process.
This can happen if the serial cable is not connected. There are hardware
pull-ups on the board connected to serial cable VBUS.
To solve this when the cable is not plugged, enable internal pull-ups as well
for the tx/rx lines.

Signed-off-by: Eugen Hristev <eugen.hris...@microchip.com>
---
 arch/arm/dts/sama7g5ek.dts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/dts/sama7g5ek.dts b/arch/arm/dts/sama7g5ek.dts
index ff9c9eb45c..3a4fdd38a5 100644
--- a/arch/arm/dts/sama7g5ek.dts
+++ b/arch/arm/dts/sama7g5ek.dts
@@ -122,7 +122,7 @@
        pinctrl_flx3_default: flx3_default {
                pinmux = <PIN_PD16__FLEXCOM3_IO0>,
                         <PIN_PD17__FLEXCOM3_IO1>;
-               bias-disable;
+               bias-pull-up;
        };
 
        pinctrl_sdmmc0_cmd_data_default: sdmmc0_cmd_data_default {
-- 
2.25.1

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