Answer
1. Load backports driver. (Here is an example for the SDIO option.)
insmod compat/compat.ko
insmod net/wireless/cfg80211.ko
insmod net/mac80211/mac80211.ko
insmod drivers/net/wireless/laird/lrdmwl/lrdmwl.ko
insmod drivers/net/wireless/laird/lrdmwl/lrdmwl_sdio.ko
Ifconfig wlan0 up
2. Set interface as AP mode
iw dev wlan0 interface add wlan1 type __ap
3. Use hostapd utility to load hostapd.conf to enable AP.
hostapd /etc/hostapd/hostapd.conf -B (Set interface=wlan1 in hostapd.conf)