I want to use half/quarter channel bandwidth with my wifi card, below is the procedure.
get the sourcecode from http://mirror2.openwrt.org/sources/madwifi-ng-r2420-20070602.tar.gz and patched it with http://madwifi.org/ticket/1367 and could successfully compile and run.
set the regdomain of my wifi card to 0 with ath_info as well as set the countrycode to 842. But I still cannot see any change as I use iwlist to list all the channels.
I tracked down the source code I found it is the function:
ath_hal_init_channels(ah, chans, IEEE80211_CHAN_MAX, &nchan,
ic->ic_regclassids, IEEE80211_REGCLASSIDS_MAX, &ic->ic_nregclass,
cc, HAL_MODE_ALL, outdoor, xchanmode))
called by ath_getchannels()
called by ath_attach()
in file ath/if_ath.c
actually read channel information from the hardware.
but the result it read is to set every channel's ic_flags is 0xC0 which is not including the flags IEEE80211_CHAN_HALF and IEEE80211_CHAN_QUARTER. So the HAL could not be allowing me to use the half/quarter bandwidth.
Is it possible to make half/quarter bandwidth to work if I replaced the HAL 0.9.30.13 with some other versions?
Thank you very much.