/etc/network/interfaces.ap-mode

auto lo
iface lo inet loopback

auto eth0
allow-hotplug eth0
iface eth0 inet manual

auto wlan0
allow-hotplug wlan0
iface wlan0 inet static
       address 192.168.0.254
       up /etc/init.d/hostapd start
       up /etc/init.d/dnsmasq start
       up /sbin/ifconfig wlan0 192.168.0.254 # workaround for race condition
       down /etc/init.d/hostapd stop
       down /etc/init.d/dnsmasq stop