#!/bin/bash

###
# This script automate the setup of QMI supported wwan devices.
#
# Tested on following environment:
#   * Lenovo ThinkPad X220 (4286-CTO)
#   * Gentoo/Linux, Linux Kernel 3.9.6
#   * NTT Docomo UIM card (Xi LTE SIM)
#   * Sierra Wireless, Inc. Gobi 3000 wireless wan module
#     (FRU 60Y3257, vendor and device id is 1199:9013)
#     memo:
#       I recommend to check if your wwan module works fine
#       for your mobile broadband provider with Windows
#       especially if you imported the device from other country.
#       You may have to initialize your device for your region.
#   * Required kernel config (other modules may be also required):
#     - qmi_wwan (CONFIG_USB_NET_QMI_WWAN)
#     - qcserial (CONFIG_USB_SERIAL_QUALCOMM)
#   * Required settings:
#     - you may have to create /etc/qmi-network.conf.
#       My qmi-network.conf has only a line "APN=mopera.net".
#

# your wwan device name created by qmi_wwan kernel module
# check it with "ip a" or "ifconfig -a". it may be wwan0?
WWAN_DEV=wwp0s29u1u4
# your cdc_wdm modem location
CDC_WDM=/dev/cdc-wdm0
# this script uses following qmi commands
QMICLI=/usr/bin/qmicli
QMI_NETWORK=/usr/bin/qmi-network
# the places of following commands vary depending on your distribution
IFCONFIG=/bin/ifconfig
DHCPCD=/sbin/dhcpcd
SUDO=/usr/bin/sudo

function helpmsg {
    echo "usage: $0 {start|stop|restart|status}"
    exit 1
}

function qmi_start {
    $COMMAND_PREFIX $IFCONFIG $WWAN_DEV up
    $COMMAND_PREFIX $QMICLI -d $CDC_WDM --dms-set-operating-mode=online
    if [ $? -ne 0 ]; then
	echo "your wwan device may be RFKilled?"
	exit 1
    fi
    $COMMAND_PREFIX $QMI_NETWORK $CDC_WDM start
    $COMMAND_PREFIX $DHCPCD $WWAN_DEV
}

function qmi_stop {
    $COMMAND_PREFIX $QMI_NETWORK $CDC_WDM stop
    $COMMAND_PREFIX kill `cat /var/run/dhcpcd-${WWAN_DEV}.pid`
    $COMMAND_PREFIX $IFCONFIG $WWAN_DEV down
}

function qmi_strength {
    dbm=`$COMMAND_PREFIX $QMICLI -d $CDC_WDM --nas-get-signal-strength | tr "'" " " | grep Network | head -1 | awk '{print $4}'`
    echo -n "Signal strength is "
    if [ $dbm -ge -73 ]; then
	echo -n 'Excellent'
    elif [ $dbm -ge -83 ]; then
	echo -n 'Good'
    elif [ $dbm -ge -93 ]; then
	echo -n 'OK'
    elif [ $dbm -ge -109 ]; then
	echo -n 'Marginal'
    else
	echo Unknown
    fi
    echo " (${dbm} dBm)"
}

function qmi_status {
    $COMMAND_PREFIX $QMI_NETWORK $CDC_WDM status
    qmi_strength
}

# check argument number
if [ $# -ne 1 ]
then
    helpmsg
fi

# check permission
if [ `whoami` != 'root' ]
then
    echo "warning: root permission required. setting command prefix to 'sudo'."
    COMMAND_PREFIX=$SUDO
fi

# run commands
case $1 in
    start) qmi_start ;;
    stop) qmi_stop ;;
    restart) qmi_stop; qmi_start ;;
    status) qmi_status ;;
    *) helpmsg ;;
esac