ath9k is working fine with hostapd offering AP mode:
root@OpenWrt:/# hostapd -dd /etc/hostapd.conf
Configuration file: /etc/hostapd.conf
Opening raw packet socket for ifindex -1209973692
BSS count 1, BSSID mask ff:ff:ff:ff:ff:ff (0 bits)
SIOCGIWRANGE: WE(compiled)=22 WE(source)=21 enc_capa=0xf
Failed to update rate sets in kernel module
RATE[0] rate=10 flags=0x2
RATE[1] rate=20 flags=0x2
RATE[2] rate=55 flags=0x2
RATE[3] rate=110 flags=0x2
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
Could not set passive scanning: Unknown error -1
Flushing old station entries
Deauthenticate all stations
Mode: IEEE 802.11g Channel: 1 Frequency: 2412 MHz
Failed to set CTS protect in kernel driver
Failed to set Short Slot Time option in kernel driver
Could not set preamble for kernel driver
Using interface wlan0 with hwaddr 00:0b:6b:b0:21:fa and ssid 'awmn'
Failed to set CTS protect in kernel driver
Failed to set Short Slot Time option in kernel driver
Could not set preamble for kernel driver
wlan0: Setup of interface done.
MGMT (TX callback) ACK
Wireless event: cmd=0x8b04 len=12
wlan0 IEEE 802.11abgn ESSID:"awmn"
Mode:Master Frequency:2.412 GHz Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Encryption key:off
Power Management:off
Link Quality:0 Signal level:0 Noise level:0
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
mon.wlan0 IEEE 802.11abgn Mode:Monitor Frequency:2.412 GHz Tx-Power=27 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Encryption key:off
Power Management:off
Link Quality:0 Signal level:0 Noise level:0
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
wlan0 IEEE 802.11abgn ESSID:"awmn"
Mode:Managed Frequency:2.412 GHz Access Point: 00:0B:6B:B0:21:FA
Bit Rate=1 Mb/s Tx-Power=23 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Encryption key:off
Power Management:off
Link Quality=50/100 Signal level:-63 dBm Noise level=-95 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0
I was only able to use 802.11g mode under hostapd, here are some iperf benchmarks:
root@OpenWrt:/# iperf -c 192.168.100.1 -u -b 100m
------------------------------------------------------------
Client connecting to 192.168.100.1, UDP port 5001
Sending 1470 byte datagrams
UDP buffer size: 107 KByte (default)
------------------------------------------------------------
[ 5] local 192.168.100.2 port 43263 connected with 192.168.100.1 port 5001
[ 5] 0.0-10.0 sec 24.3 MBytes 20.3 Mbits/sec
[ 5] Sent 17302 datagrams
[ 5] Server Report:
[ 5] 0.0-10.0 sec 24.3 MBytes 20.3 Mbits/sec 0.125 ms 0/17301 (0%)
[ 5] 0.0-10.0 sec 1 datagrams received out-of-order