MT7922 Only first access point associates with radio

For Developers
1

This is a recently supported device.

I have the MT9722 onboard my MSI PRO B650-VC WIFI (hardware v1.2). I have Proxmox VE installed as the host OS. I have 23.05.3 r23809-234f1a2efa installed as a guest and I have enabled PCI-E passthrough for the MT9722 wireless adapter. Everything works using the tips provided at kjames2001/OpenWRT-PVE-AP-MT7922: guide to run OpenWRT on PVE with Access Point through m.2 wifi module MT7922 (github.com). (I already had Proxmox VE with PCI-E GPU passthrough working before I started this, so I didn't need to follow all the instructions.)

As indicated by the GitHub author, kjames2001, this driver comes up with a dead AP on boot, so you do have to restart the radio after booting up. The Startup script helps perform that task. But even when you restart all the configured access points (separate VLANs), only the first one associates. The others say "Wireless is not associated," even when you restart all of them. At no point will more than one access point associate at the same time, in contrast to what does work with the ath79/QCA9886 or the mt7622 driver, for instance, where I have 7 VLANs on 7 SSIDs all configured and associated on 7 wireless access points with no problems.

I'm not sure if it has anything to do with the interface saying something like "Generic MAC80211 802.11ac/ax/b/g/n" instead of the device name. I just figured I'd see if anyone else with this MT9722 chipset has the same trouble.

In my case, I have a community Wi-Fi setup where each access point is configured for all the VLANs and associates a different VLAN with each SSID and there are other dedicated wired and wireless for the backhauls. This configuration does work on all my other access points, but I figured since I have a nice built-in card in my PC, that would be another good access point. Not so much with only one access point associating, but I am using it just for the one VLAN I use for most of my devices.

I wonder if it's a software thing or a hardware thing. The 6G doesn't work at all (using LUCI configuration), but that's not a deal-breaker. The 5G will be fine until we can work that out. I guess you can't use both radios at the same time either. It makes you select 2.4, 5, or 6 GHz for the radio, which I suppose may be normal given the device it is supposed to be, wireless station, rather than AP.

Also, since I am one of the few people that probably have this chipset and I have a virtual computing environment to use it in, I may be able to offer specific data points to anyone working on the MT7922 support. So let me know if there's anything I can do to help. Thanks!

2

That is not an issue at all and merely cosmetic. iwinfo contains a hardcoded mapping between PCI IDs and 'pretty names', which obviously won't know about all devices - and is just for show anyways, it bears no functional consequence (at all).

I assume you're referring to mt7922 here. Be aware that contrary to mt7915/ mt7916, mt7921/ mt7922 are client centric chipsets, which lack features compared to the AP centric chipsets - this primarily affects the maximum number of connected clients, as well as the allowed interface combinations (check iw list for details). While I don't have mt7922, I can only extrapolate from my mt7921:

$ /sbin/iw list
[…]
        software interface modes (can always be added):
                 * AP/VLAN
                 * monitor
        valid interface combinations:
                 * #{ managed, P2P-client } <= 2, #{ AP, P2P-GO } <= 1,
                   total <= 2, #channels <= 2
[…]

…in other words, there can only be <= 1 AP concurrent interface active.

mt7922 is tri-band, but not concurrent tri-band, you can only select a single band at a time. In order to serve all three band, you'd need three of these cards (or one mt7915 in DBDC mode covering 2.4+5 GHz and something for 6 GHz).

3

This topic was automatically closed 10 days after the last reply. New replies are no longer allowed.