error in setting hostapd file

i use ralink wifi adapter for creating wireless network mt7601 firnwre. so while configuring the hostapd.conf file i encountered an error saying drivers not initialized ` interface used by access point interface=wlan0

firmware driver

driver=nl80211

access point SSID

ssid=rpiap

operation mode (a = IEEE 802.11a, b = IEEE 802.11b, g = IEEE 802.11g)

hw_mode=g

access point channel

channel=6

macaddr_acl=0 auth_algs=1 ignore_broadcast_ssid=0

key management algorithm

wpa_key_mgmt=WPA-PSK wpa_passphrase=mypasscode wpa=2

set ciphers

wpa_pairwise=TKIP rsn_pairwise=CCMP `

The error shows

root@Sharebox:/home/pi# hostapd -d /etc/hostapd/hostapd.conf random: Trying to read entropy from /dev/random Configuration file: /etc/hostapd/hostapd.conf ctrl_interface_group=0 Line 8: invalid/unknown driver 'nl80211' 1 errors found in configuration file '/etc/hostapd/hostapd.conf'

can anyone help??