Disables on-board Ethernet to fix Raspberry Pi WiFi+Lapdock

disable-ethernet.sh

#!/bin/bash
 
### BEGIN INIT INFO
# Provides:          disable-ethernet
# Required-Start:    $local_fs
# Required-Stop:     
# Default-Start:     S
# Default-Stop:      
# Short-Description: Disables on-board Ethernet to fix WiFi+Lapdock
# Description:       When using the Raspberry Pi Model B on the
#                    Motorola Atrix Lapdock, inserting certain WiFi
#                    adapters into either the RPi's spare USB port or
#                    the Lapdock's USB ports causes the on-board
#                    Ethernet and WiFi adapter to malfunction.
#                    Disabling the on-board Ethernet driver allows
#                    the WiFi adapter to work simultaneously with the
#                    Lapdock.
### END INIT INFO
 
. /lib/lsb/init-functions
 
DEVICE_DIR=/sys/bus/usb/drivers/smsc95xx
BUS_ID="1-1.1:1.0"
INT_TOGGLE=true #issue ifdown and ifup?
#INT_TOGGLE=false
 
is_enabled () {
    [ -L "$DEVICE_DIR/$BUS_ID" ] && return 0 || return 1
}
 
toggle_int () {
    is_enabled || return 0 #ethernet not enabled
    [ "$(ls -1 "$DEVICE_DIR/$BUS_ID/net" |wc -l)" -eq "1" ] || return 0 #something wrong
    $INT_TOGGLE || return 0 #user doesn't want this
    [ ! -f /run/network/ifstate ] && return 0 #run level S
    int_name=$(ls -1 "$DEVICE_DIR/$BUS_ID/net")
    if [ "$1" == "up" ]; then
        log_action_begin_msg "Bringing on-board interface up"
        ifup $int_name
    else
        log_action_begin_msg "Bringing on-board interface down"
        ifdown $int_name
    fi
    log_action_end_msg $?
}
 
case "$1" in
    start)
        if ! is_enabled; then
            log_failure_msg "Service already running. Exiting."
            exit 0
        fi
        toggle_int down
        log_action_begin_msg "Disabling on-board network interface"
        echo "$BUS_ID" > $DEVICE_DIR/unbind
        log_action_end_msg $?
        exit $?
        ;;
    restart|reload|force-reload)
        echo "Error: argument '$1' not supported" >&2
        exit 3
        ;;
    stop)
        if is_enabled; then
            log_failure_msg "Service not running. Exiting."
            exit 0
        fi
        log_action_begin_msg "Enabling on-board network interface"
        echo "$BUS_ID" > $DEVICE_DIR/bind
        log_action_end_msg $?
        toggle_int up
        exit $?
        ;;
    status)
        if is_enabled; then
            echo "Service is NOT running: on-board interface enabled" >&2
            exit 1
        else
            echo "Service is running: on-board interface disabled"
            exit 0
        fi
        ;;
    *)
        echo "Usage: $0 start|stop|status" >&2
        exit 3
        ;;
esac