From: Eugen Hristev <eugen.hristev@microchip.com>
Date: Thu, 28 Jan 2021 08:14:11 +0000 (+0200)
Subject: ARM: dts: at91: sama7g5ek: enable pull-up for serial debug line
X-Git-Url: http://git.dujemihanovic.xyz/%7B%7B%20%24style.RelPermalink%20%7D%7D?a=commitdiff_plain;h=5dc68b07e75d4695a554b60135d70f1847885bd2;p=u-boot.git

ARM: dts: at91: sama7g5ek: enable pull-up for serial debug line

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.hristev@microchip.com>
---

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 {