use duo-init.sh to initialize some hardware interfaces

buildroot-2021.05/board/milkv/duo/overlay/etc/init.d/S99user

@@ -15,6 +15,10 @@ case "$1" in
 
         echo "Starting app..."
 
+        if [ -f $SYSTEMPATH/duo-init.sh ]; then
+                . $SYSTEMPATH/duo-init.sh &
+        fi
+
         if [ -f $SYSTEMPATH/blink.sh ]; then
                 . $SYSTEMPATH/blink.sh &
         fi

milkv/overlay/mnt/system/duo-init.sh

+#!/bin/sh
+
+# set PWR_GPIO[4] to gpio
+devmem 0x0502707c 32 0x111
+devmem 0x03001068 32 0x3
+