Auto scan and set unused Wifi channel for Phantom 3 Standard / 4K

setchan

#!/bin/sh
#Auto scan and set unused Wifi channel for Phantom 3 Standard / 4K
#Author : Gary Kan
#Date : 20/06/2016
#Version 1.1
#	1) Add new user argument option
#		-ch for set channel number, eg. -ch 13
#		-booster will limit RC tx power to 20DBM, to protect your external booster
#	2) Add Restart udhcp and apsvr
#	3) Some Minor tweak
#
#Date : 21/06/2016
#Version1.2
#	1) Remove user argument option -booster
#	2) Remove apsvr due to my RC video link sometime get disconnected
#	4) Change Default DBM from 27dbm to 24 dbm on RC and drone, due to user report his RC is bricked despite of successful application of 27dbm setting, after fifth flight.
#	3) Add new user argument option
#		-rc will limit RC tx power to your target mbm, eg -rc 2000 = 20DBm, Max = 2700
#		-d will limit DRONE tx power to your target mbm, eg -d 2000 = 20DBm, Max = 2700
#
clear
DRONE="192.168.1.2"


###For check User argument
while [ "$1" != "" ]; do
	case $1 in
		-ch)
			shift
			SCAN="OFF"
			CHANNEL=$1
			;;
		-rc)
			shift
			RC="Y"
			RCDBM=$1
			echo "Info : Limit RC TX Power to $1"
			;;
		-d)
			shift
			D="Y"
			DDBM=$1
			echo "Info : Limit Drone TX Power to $1"
			;;
		-h)
			echo "-ch for set channel number, eg. -ch 13"
			echo "-rc will limit RC tx power to your target mbm, eg -rc 2000 = 20DBm, Option = 1700 2000 2400 2700"
			echo "-d will limit DRONE tx power to your target mbm, eg -d 2000 = 20DBm, Option = 1700 2000 2400 2700"
			echo "-h for show this page"
			exit
			;;
		* )
			echo "Incorrect user argument !!" 
			echo "-ch for set channel number, eg. -ch 13"
			echo "-rc will limit RC tx power to your target mbm, eg -rc 2000 = 20DBm, Option = 1700 2000 2400 2700"
			echo "-d will limit DRONE tx power to your target mbm, eg -d 2000 = 20DBm, Option = 1700 2000 2400 2700"
			echo "-h for show this page"
			exit 1
			;;
	esac
	shift
done

###Make Sure network is ready and Drone side is online
echo "Checking Connection with Phantom 3 Standard / 4K . . ."
ping -c 1 -w 60 $DRONE &> /dev/null
if [ $? -ne 0 ]
then
        echo "ERROR : Phantom 3 Standard / 4K at $DRONE is unreachable"
        exit 1
else
	echo "Connection - OK."
fi


###Check unused channel or user argument 
if [ "$SCAN" != "OFF" ]
then
	for i in 1 2 3 4 5 6 7 8 9 10 11 12 13
	do
		iw dev wlan0 scan | grep "DS Parameter set:" | awk '{FS=" "} {print $5}' | sort -n | grep -x $i &>/dev/null
		if [ $? -ne 0 ]
		then
			echo "Channel $i - Not In Use"
			echo "Set CH to $i"
			CH=$i
			break
		else
			echo "Channel $i - In Use"
			if [ $i = 13 ]
			then
				CH=$i
			fi
		fi
	done
else
	echo "User Input Channel = $CHANNEL"
	case $CHANNEL in
		1|2|3|4|5|6|7|8|9|10|11|12|13)
			CH=$CHANNEL
			;;
		*) 
			echo "Input Error : Channel must be 1 to 13 !!"
                        exit 1
			;;
	esac
fi


###Setup hostapd-phy0.conf with target channel number
echo "Trying To Set Channel = $CH . . ."
sed -i "/channel=/c\channel=$CH" /tmp/run/hostapd-phy0.conf
echo "Patched `grep "channel" /tmp/run/hostapd-phy0.conf`"
echo " "


###patch drone side to BO, make sure ready for CH12,13, telnet.d must be on in rcS, scan be remove is user set country = BO in rcS at drone side
echo "Checking Connection with Phantom 3 Standard / 4K . . ."
ping -c 1 -w 30 $DRONE &> /dev/null
if [ $? -ne 0 ]
then
	echo "ERROR : Phantom 3 Standard / 4K at $DRONE is unreachable"
	exit 1
else
	echo "Connected . . ."
	echo "Patching Phantom 3 Standard / 4K at $DRONE . . ."
	if [ "$D" = "Y" ]
	then
		{ sleep 1;echo "iw reg get";echo "iw reg set BO";echo "iw reg get";echo "iw dev wlan0 set txpower limit $DDBM";sleep 1;} | telnet $DRONE
	else
		{ sleep 1;echo "iw reg get";echo "iw reg set BO";echo "iw reg get";echo "iw dev wlan0 set txpower limit 2400";sleep 1;} | telnet $DRONE
	fi
fi


###Patch RC Side and restart network
echo ""
echo "Patching Phantom 3 Standard / 4K  - RC . . ."
iw reg set BO
if [ "$RC" = "Y" ]
then
	echo "Info : Limit RC TX Power to $RCDBM"
	iw dev wlan0 set txpower limit $RCDBM
else
	iw dev wlan0 set txpower limit 2400
fi
sleep 1

echo ""
echo "Restarting Services, it may take a moment . . ." 
kill -9 `ps | grep udhcpd | grep -v grep | awk '{print $1}'`
sleep 3
kill -9 `cat /tmp/run/wifi-phy0.pid`
sleep 3
#kill -9 `ps | grep apsrv | grep -v grep | awk '{print $1}'`
#sleep 5

/usr/sbin/hostapd -P /var/run/wifi-phy0.pid -B /var/run/hostapd-phy0.conf
sleep 3
#apsrv &
#sleep 3
/usr/sbin/udhcpd -S /etc/udhcpd.conf &
sleep 3


###Final Checking, can be remove
echo ""
echo "Listing Services . . ."
ps | grep hostapd | grep -v grep
ps | grep apsrv | grep -v grep
ps | grep udhcpd | grep -v grep

echo ""
echo "Checking Final Result at $DRONE . . ."
ping -c 1 -w 60 $DRONE &> /dev/null
if [ $? -ne 0 ]
then
        echo "ERROR : Phantom 3 Standard / 4K at $DRONE is unreachable"
        exit 1
else
        { sleep 1;echo "iwinfo";sleep 1;} | telnet $DRONE
	echo ""
	echo "Checking Final Result at RC . . ."
	iwinfo
	echo "Patch Completed, Enjoy."
fi