How to test WLAN function via command line

wifiTest

When a PCB back from product line without LCD, how to test WIFI basic function?
We can usually use below commands in adb shell with root permission

//Check if wlan.ko was loaded
lsmod

//If not, please install it
insmod /system/lib/modules/wlan.ko

//Check if it correctly installed
lsmod
    // For example, the message below indicates wlan driver is loaded successsfully
    wlan 3820391 0 - Live 0x00000000 (O)

// copy wpa_supplicant.conf to /data/misc/wifi for testing purpose and change ownership of wpa_supplicant.conf to allow wpa_supplicant to read
cp /system/etc/wifi/wpa_supplicant.conf /data/misc/wifi/
chown system:wifi /data/misc/wifi/wpa_supplicant.conf

//Enable wpa_supplicant
wpa_supplicant -iwlan0 -Dnl80211 -c/data/misc/wifi/wpa_supplicant.conf -O/data/misc/wifi/sockets -ddd &

//Use 'ps' command to check if wpa_supplicant is enabled successfully
ps wpa_supplicant
    // For example, the message below indicates wpa_supplicant is enabled successfully
    ps wpa_supplicant
    USER     PID   PPID  VSIZE  RSS     WCHAN    PC         NAME
    wifi      3321  1     3436   1916  c0263cac b6ed3824 S wpa_supplicant
    // Any failure, please check logcat for the reason

//Execute wpa_cli for scan and connection testing in adb shell
wpa_cli -i wlan0 -p /data/misc/wifi/sockets

//Scan the available APs nearby, use scan command in wpa_cli
> scan
    //following message indicates scan is done
    <3>CTRL-EVENT-SCAN-RESULTS

//Check scan results
> scan_results

//adb pull /data/misc/wifi/wpa_supplicant.conf and add the AP profile for association testing
//change ctrl_interface parameter to /data/misc/wifi
ctrl_interface=/data/misc/wifi/sockets

// For AP without security, add
network={
        # The ssid of the AP is AP_WITHOUT_SECURITY
ssid="AP_WITHOUT_SECURITY"
key_mgmt=NONE
}

// For AP using WEP security with passphrase 1234567890 and key index 1, add
network={
ssid="AP_WEP_SECURITY"
key_mgmt=NONE
auth_alg=OPEN SHARED
wep_key0=1234567890
}

//For AP using WPA-PSK/WPA2-PSK mixed mode, add
network={
ssid="CH5_OPEN_TEST"
key_mgmt=WPA-PSK
psk="1234567890"
}

// adb push wpa_supplicant.conf back to /data/misc/wifi with new settings and enforce wpa_supplicant to read new configuration setting by executing "reconfigure" command in wpa_cli
> reconfigure

// wpa_supplicant would trigger auto connection to the APs set in wpa_supplicant.conf
    //Following message indicates association is successfully made
    <3>CTRL-EVENT-CONNECTED - Connection to ec:1a:59:8c:5d:88 completed (auth) [id=0 id_str=]

//Suppose the AP's IP address is 192.168.0.1, set the DUT's IP address to same network like 192.168.0.100
ifconfig wlan0 192.168.0.100

//Ping AP's address
ping 192.168.0.1

//When test is done, remove temporarily created /data/misc/wifi/wpa_supplicant.conf
rm /data/misc/wifi/wpa_supplicant.conf