在應用AR1021X模塊化集成時，一些應用需要用模塊來做soft ap使用，這就牽涉到hostapd配置問題，如果配置不好，是沒有SSID熱點出來！模塊有支持雙頻的，有只支持單頻的，具體要認真閱讀模塊規格書,所以配置的時候要留意！

一般根據對應的Kernel內核版本提供的驅動包，保障物理連接正常，供電穩定，正常編譯驅動后，就能加載成功，并正常使用！

以下案例現象：使用hostapd配置AP熱點，ap熱點出不來!

log信息如下：

ostapd -dd -e /dev/urandom /etc/hostapd.conf &

# random: Invalid entropy file /dev/urandom

random: TryinADDRCONF(NETDEV_UP): wlan0: link is not ready

g to read entropy from /dev/random

Get randomness: len=20 entropy=0

random: Updated entropy file /dev/urandom (own_pool_ready=0)

Configuration file: /etc/hostapd.conf

nl80211: interface wlan0 in phy phy0

rfkill: initial event: idx=0 type=1 op=0 soft=0 hard=0

nl80211: Supports Probe Response offload in AP mode

nl80211: Disable use_monitor with device_ap_sme since no monitor mode support detected

nl80211: Add own interface ifindex 4

nl80211: Set mode ifindex 4 iftype 3 (AP)

nl80211: Setup AP - device_ap_sme=1 use_monitor=0

nl80211: Subscribe to mgmt frames with AP handle 0x102ee00 (device SME)

nl80211: Register frame type=0xd0 nl_handle=0x102ee00

nl80211: Register frame match - hexdump(len=0): [NULL]

nl80211: Enable Probe Request reporting nl_preq=0x102ed98

nl80211: Register frame type=0x40 nl_handle=0x102ed98

nl80211: Register frame match - hexdump(len=0): [NULL]

BSS count 1, BSSID mask 00:00:00:00:00:00 (0 bits)

nl80211: Regulatory information - country=US

nl80211: 2402-2472 @ 40 MHz

nl80211: 5170-5250 @ 40 MHz

nl80211: 5250-5330 @ 40 MHz

nl80211: 5490-5730 @ 40 MHz

nl80211: 5735-5835 @ 40 MHz

nl80211: Added 802.11b mode based on 802.11g information

Allowed channel: mode=1 chan=1 freq=2412 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=2 freq=2417 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=3 freq=2422 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=4 freq=2427 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=5 freq=2432 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=6 freq=2437 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=7 freq=2442 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=8 freq=2447 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=9 freq=2452 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=10 freq=2457 MHz max_tx_power=30 dBm

Allowed channel: mode=1 chan=11 freq=2462 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=36 freq=5180 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=40 freq=5200 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=44 freq=5220 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=48 freq=5240 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=149 freq=5745 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=153 freq=5765 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=157 freq=5785 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=161 freq=5805 MHz max_tx_power=30 dBm

Allowed channel: mode=2 chan=165 freq=5825 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=1 freq=2412 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=2 freq=2417 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=3 freq=2422 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=4 freq=2427 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=5 freq=2432 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=6 freq=2437 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=7 freq=2442 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=8 freq=2447 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=9 freq=2452 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=10 freq=2457 MHz max_tx_power=30 dBm

Allowed channel: mode=0 chan=11 freq=2462 MHz max_tx_power=30 dBm

Completing interface initialization

Mode: IEEE 802.11g Channel: 6 Frequency: 2437 MHz

nl80211: Set freq 2437 (ht_enabled=1 sec_channel_offset=0)

RATE[0] rate=10 flags=0x1

RATE[1] rate=20 flags=0x1

RATE[2] rate=55 flags=0x1

RATE[3] rate=110 flags=0x1

RATE[4] rate=60 flags=0x0

RATE[5] rate=90 flags=0x0

RATE[6] rate=120 flags=0x0

RATE[7] rate=180 flags=0x0

RATE[8] rate=240 flags=0x0

RATE[9] rate=360 flags=0x0

RATE[10] rate=480 flags=0x0

RATE[11] rate=540 flags=0x0

wlan0: Flushing old station entries

wlan0: Deauthenticate all stations

wpa_driver_nl80211_set_key: ifindex=4 alg=0 addr=(nil) key_idx=0 set_tx=0 seq_len=0 key_len=0

wpa_driver_nl80211_set_key: ifindex=4 alg=0 addr=(nil) key_idx=1 set_tx=0 seq_len=0 key_len=0

wpa_driver_nl80211_set_key: ifindex=4 alg=0 addr=(nil) key_idx=2 set_tx=0 seq_len=0 key_len=0

wpa_driver_nl80211_set_key: ifindex=4 alg=0 addr=(nil) key_idx=3 set_tx=0 seq_len=0 key_len=0

Using interface wlan0 with hwaddr 38:e2:6e:0c:04:1f and ssid 'ar1021_wifi'

Deriving WPA PSK based on passphrase

SSID - hexdump_ascii(len=11):

61 72 31 30 32 31 5f 77 69 66 69 ar1021_wifi

PSK (ASCII passphrase) - hexdump_ascii(len=8): [REMOVED]

PSK (from passphrase) - hexdump(len=32): [REMOVED]

random: Cannot read from /dev/random: Resource tempoADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready

rarily unavailable

random: Got 0/20 bytes from /dev/random

random: Only 0/20 bytes of strong random data available from /dev/random

random: Not enough entropy pool available for secure operations

WPA: Not enough entropy in random pool for secure operations - update keys later when the first station connects

Get randomness: len=32 entropy=0

GMK - hexdump(len=32): [REMOVED]

Get randomness: len=32 entropy=0

Key Counter - hexdump(len=32): [REMOVED]

WPA: Delay group state machine start until Beacon frames have been configured

hostapd_eid_deny_mac num_deny_mac:0

hostapd_eid_accept_mac num_accept_mac:0

nl80211: Set beacon (beacon_set=0)

WPA: Start group state machine to set initial keys

WPA: group state machine entering state GTK_INIT (VLAN-ID 0)

Get randomness: len=16 entropy=0

GTK - hexdump(len=32): [REMOVED]

WPA: group state machine entering state SETKEYSDONE (VLAN-ID 0)

wpa_driver_nl80211_set_key: ifindex=4 alg=2 addr=0x6a828 key_idx=1 set_tx=1 seq_len=0 key_len=32

broadcast key

wpa_driver_nl80211_set_operstate: operstate 0->1 (UP)

netlink: Operstate: linkmode=-1, operstate=6

Failed to set TX queue parameters for queue 0.

Failed to set TX queue parameters for queue 1.

Failed to set TX queue parameters for queue 2.

Failed to set TX queue parameters for queue 3.

wlan0: Setup of interface done.

RTM_NEWLINK: operstate=1 ifi_flags=0x1002 ()

nl80211: Ignore interface down event since interface wlan0 is up

RTM_NEWLINK: operstate=1 ifi_flags=0x1043 ([UP][RUNNING])

RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added

nl80211: if_removed already cleared - ignore event

RTM_NEWLINK: operstate=1 ifi_flags=0x1003 ([UP])

RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added

nl80211: if_removed already cleared - ignore event

RTM_NEWLINK: operstate=1 ifi_flags=0x1003 ([UP])

RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added

nl80211: if_removed already cleared - ignore event

nl80211: Event message available

nl80211: Regulatory domain change

wlan0: Event CHANNEL_LIST_CHANGED (31) received

Unknown event 31

nl80211: Event message available

nl80211: Regulatory domain change

wlan0: Event CHANNEL_LIST_CHANGED (31) received

Unknown event 31

RTM_NEWLINK: operstate=1 ifi_flags=0x11043 ([UP][RUNNING][LOWER_UP])

RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added

nl80211: if_removed already cleared - ignore event

RTM_NEWLINK: operstate=1 ifi_flags=0x11003 ([UP][LOWER_UP])

netlink: Operstate: linkmode=-1, operstate=6

RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added

nl80211: if_removed already cleared - ignore event

RTM_NEWLINK: operstate=1 ifi_flags=0x11043 ([UP][RUNNING][LOWER_UP])

RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added

nl80211: if_removed already cleared - ignore event

hostapd.conf配置如下：

interface=wlan0

driver=nl80211

ssid=ar1021_wifi

channel=6

hw_mode=g

ignore_broadcast_ssid=0

auth_algs=1

wpa=3

wpa_passphrase=88888888

wpa_key_mgmt=WPA-PSK

wpa_pairwise=TKIP

rsn_pairwise=CCMP

iwconfig：

# iwconfig

lo no wireless extensions.

eth0 no wireless extensions.

sit0 no wireless extensions.

wlan0 IEEE 802.11abgn Mode:Master Frequency:2.437 GHz Tx-Power=17 dBm

Retry long limit:7 RTS thr:off Fragment thr:off

Power Management:off

p2p0 IEEE 802.11abgn ESSID:off/any

Mode:Managed Access Point: Not-Associated Tx-Power=17 dBm

Retry long limit:7 RTS thr:off Fragment thr:off

Encryption key:off

Power Management:off

以上信息很明顯，是針對只能支持ISM5.8G頻段的模塊，hostapd.conf配置成了ISM2.4G，只要進行重新配置就可以了！同時提醒，雙頻是分時雙頻，也就是工作時候只能支持一種，但是有兩種頻供選！或者理解成雙頻供選擇，實際選用一種！

針對AR1021X系列WiFi模塊(SR6225UE、SR6224UE、SR6221UE、SR6235UE、SR5223UD)，編譯加載的問題，可以提供Log信息，配合有效分析！