(good info on guest support in ap mode) mt7612u DFS support

[soyersoyer]

Great summary!

You can add some more info: The mt7612u(n) doesn't support DFS, but it can use that channels with different reg domain. The multi ap mode (guest ap mode) works too.

[morrownr]

Quote: "The multi ap mode (guest ap mode) works too."

Do you have an example you would share of setting up the guest mode?

Thanks.

[soyersoyer]

Of course! I am using a COMFAST CF-WU782AC adapter. My hostapd.conf:

interface=wlan0
ssid=ssid0
bssid=e2:aa:bb:cc:dd:ee

hw_mode=a
channel=36

ieee80211n=1
ht_capab=[LDPC][SHORT-GI-20][SHORT-GI-40][HT40+][GF][TX-STBC][RX-STBC1]

ieee80211ac=1
vht_capab=[RXLDPC][SHORT-GI-80][TX-STBC-2BY1][RX-STBC-1][MAX-A-MPDU-LEN-EXP3][TX-ANTENNA-PATTERN][RX-ANTENNA-PATTERN]

vht_oper_chwidth=1
vht_oper_centr_freq_seg0_idx=42

ieee80211d=1
#ieee80211h=1
country_code=US

wmm_enabled=1


macaddr_acl=0
auth_algs=1
wpa=2
wpa_key_mgmt=WPA-PSK
wpa_pairwise=CCMP
wpa_passphrase=pass0
ap_isolate=1


bss=wlan1
ssid=ssid1
bssid=e6:aa:bb:cc:dd:ee
auth_algs=1
wpa=2
wpa_key_mgmt=WPA-PSK
wpa_pairwise=CCMP
wpa_passphrase=pass1

The trick is, you have to manually set the bssids, and the first one first byte have to be masked with 0x02 and the second one first byte with 0x06.

This is because the driver uses the NEW_MULTI_BSSID_MODE:

New BSSID numbering rule:
a. Bit0 of MAC address Byte0 is broadcast/multicast bit.
b. Bit1 of MAC address Byte0 is local administration bit
and should be set to 1 in extended multiple BSSIDs’.
c. Bit4:Bit3 of MAC address Byte0 is extended multiple
BSSID index.
For example: in 4-BSSID mode and MAC address is
00:0c:43:28:60:01,
by new rule, the extended 3-BSSID is
02:0c:43:28:60:01 and
06:0c:43:28:60:01 and
0a:0c:43:28:60:01.

[morrownr]

Thanks. I'm going to have to try that on my RasPi4b access point. And I will get it documented.

Any possibility of getting you write a review and providing a link or two for the COMFAST CF-WU782AC adapter? I have a couple of links for it but without having one, there is only so much I can write about.

Cheers,

Nick

[soyersoyer]

It works well with my rasPi4b. I had to disable the usb_sg. I like this setup because it can route near gigabit (with a tp-link ue300), my mobile devices have 300-500mbit/s download speed too, it has guest wifi, and I can easily switch to a newer wifi adapter later. The rpi runs kodi, a shairport server and a bluetooth sound receiver server too. I bought the wifi adapter from https://www.aliexpress.com/item/32902591576.html Bests, s

[morrownr]

@soyersoyer

Quote: "The mt7612u(n) doesn't support DFS"

I finally had time this morning to check this issue. My client system is using an ALFA AWUS036ACM (mt7612u) adapter and the wifi router has been changed to channel 52, which is a DFS channel here in the US. My intent is to make this a long term test and try all of the DFS channels to get results. Can I get you to go over your results again as it looks to me like the mt76 drivers and the adapters do support DFS channels? At least the support appears to be there in client mode. I have not tested AP mode yet.

[Medullitus]

@soyersoyer

Quote: "The mt7612u(n) doesn't support DFS"

I finally had time this morning to check this issue. My client system is using an ALFA AWUS036ACM (mt7612u) adapter and the wifi router has been changed to channel 52, which is a DFS channel here in the US. My intent is to make this a long term test and try all of the DFS channels to get results. Can I get you to go over your results again as it looks to me like the mt76 drivers and the adapters do support DFS channels? At least the support appears to be there in client mode. I have not tested AP mode yet.

When will you test the AP mode?

[morrownr]

When will you test the AP mode?

I have. DFS is not supported currently. I'm trying to work the issue.

[morrownr]

Hi @soyersoyer

I need your take on something I am reading:

https://www.phoronix.com/scan.php?page=news_item&px=Linux-5.18-Networking

See this part:

background radar detection for the Mediatek MT76 driver

Is that DFS support? Is it just for the new 7921 or is it for the 7612 also?

Regards

[soyersoyer]

I think they wrote about these commits: https://github.com/openwrt/mt76/commit/fae295af31eb463ee3654c5c2a29ec4fe3ba03e2 https://github.com/openwrt/mt76/commit/e0f9479bf8937bc0ff7322043a7a0554b44af29f https://github.com/openwrt/mt76/commit/822e1135e7e1daba426972b8de6627f17158d8f7

[Sami32]

MT7610 and MT7612 support DFS in AP mode but it seem that their Linux driver is lacking of such support: mtk_wi-fi_softap_software_programming_guide_v4_6.pdf Possible but not certified for.

On the other side the MT7921 DFS have been certified and commited in the Linux kernel (including MT7915): MT7921-DTS-UNII-Declaration-letter-5425712.pdf DFS-report-5682031.pdf