built-in WIRELESS device is restricted to channels 1-11

[rofl0r]

it took quite a while for me to figure out why suddenly my efika's built-in WIFI couldnt see my AP anymore (whose auto-channel-switch-algorithm decided that 13 would be a good choice).
this seems to be due to a restriction to US regulations (in EUROPE its OK to use channel 12 and 13).
how can i fix that ?

[rofl0r]

# drivers/staging/rt2860/common/cmm_sync.c
# @ void BuildChannelList(struct rt_rtmp_adapter *pAd)
# - switch (pAd->CommonCfg.CountryRegion & 0x7f) {
# + switch (31 /* now we're in japan */) {

[rofl0r]

it's not possible to workaround the problem in another way since wext has no method to change regulatory domain, and the driver is wext-only, so iw reg set doesnt have any effect on it.

[serendependy]

I'm not associated with the project any more so I can't be of help, but I wanted to congratulate you for working this out. I spent months on it with no success...

[rofl0r]

@steev on IRC now pointed out that there may be another way, apparently the driver tries to read a configuration file : RT2870STA.dat

# Copy this file to /etc/Wireless/RT2870STA/RT2870STA.dat
# This file is a binary file and will be read on loading rt.o module.
#
# Use "vi RT2870STA.dat" to modify settings according to your need.
# 
# 1.) set NetworkType to "Adhoc" for using Adhoc-mode, otherwise using Infrastructure
# 2.) set Channel to "0" for auto-select on Infrastructure mode
# 3.) set SSID for connecting to your Accss-point.
# 4.) AuthMode can be "WEPAUTO", "OPEN", "SHARED", "WPAPSK", "WPA2PSK", "WPANONE"
# 5.) EncrypType can be "NONE", "WEP", "TKIP", "AES"
# for more information refer to the Readme file.
# 
#The word of "Default" must not be removed
Default
CountryRegion=5
CountryRegionABand=7
CountryCode=
SSID=Dennis2860AP
NetworkType=Infra
WirelessMode=9
Channel=0
BeaconPeriod=100
TxPower=100
BGProtection=0
TxPreamble=0
RTSThreshold=2347
FragThreshold=2346
TxBurst=1
WmmCapable=0
AckPolicy=0;0;0;0
AuthMode=OPEN
EncrypType=NONE
WPAPSK=
DefaultKeyID=1
Key1Type=0
Key1Str=
Key2Type=0
Key2Str=
Key3Type=0
Key3Str=
Key4Type=0
Key4Str=
PSMode=CAM
FastRoaming=0
RoamThreshold=70
HT_RDG=1
HT_EXTCHA=0
HT_OpMode=1
HT_MpduDensity=4
HT_BW=1
HT_AutoBA=1
HT_BADecline=0
HT_AMSDU=0
HT_BAWinSize=64
HT_GI=1
HT_MCS=33
HT_MIMOPSMode=3
IEEE80211H=0
TGnWifiTest=0
WirelessEvent=0
CarrierDetect=0

i didn't try it since my solution is now autoloaded on start

(
cd /tmp
/root/kmem_sym_dump BuildChannelList > /dev/null || { echo couldnt dump func ; exit 1 ; }
[ $(md5sum /tmp/dump.bin | cut -d " " -f 1) = 0111dfecb6260682f69f05af6359659c ] || {
        echo checksum mismatch
        exit 1
}
rm -f /tmp/dump.bin
/root/kmem_sym_patch BuildChannelList 1f50a0e3 88

# drivers/staging/rt2860/common/cmm_sync.c
# @ void BuildChannelList(struct rt_rtmp_adapter *pAd)
# - switch (pAd->CommonCfg.CountryRegion & 0x7f) {
# + switch (31 /* now we're in japan */) {
# the patch 1f50a0e3 changes the arm insn at offset 88
# - and r5, r5, 0x7f
# + mov r5, 0x1f
)

using the tools https://github.com/rofl0r/hardcore-utils/blob/master/kmem_sym_patch.c and https://github.com/rofl0r/hardcore-utils/blob/master/kmem_sym_dump.c