This is a huge issue for me and I really need help. I used to use ddwrt and it worked fine, I could enable as much as 4 devices per radio with no issues.
But since I moved to openwrt I can only enable 1 device per radio. Sometimes it will work only the first time I enable the second device but after I disable it I can't enable it until I reboot.
Any one knows how to fix this issue?
BTW, I tried many firmware for my chip 4366c0, I even tried the original asus firmware, and the ddwrt firmware, but all give the same behavior, which it mean it has to do with openwrt core.
I tried all version, 22.x and 23.x, currently I am using my own build using the latest snapshot and gcc14.0.2 and binutils 2.43.1
That is limitation is open source driver implementing only single function at once on all broadcom wifi. Openwrt "core" whatever that is supports multiple functions at the same time on ath?k and mt76 kinds of wifi.
iw list will tell you the allowed interface combinations for your radio(s), that's the feature set you get from hardware && firmware && driver. To the best of my knowledge, brcmfmac doesn't support more than one interface per radio, these are fullmac drivers with a rather fixed-function firmware after all (and it's not exactly great with basic functionality to begin with).
The Asus RT-AC88U is 4x4 should easily enable 2 devices per radio. But why it can do it upon reboot, but not after disabling the second device. That is nothing to do with the driver. It is something to do with the core?
Just curious why did you move away from DDWRT if it was functioning the way you wanted?
(I use and administer a lot of Broadcom Northstar routers (R7000, AC68U, EA6900) which run DDWRT, these old routers are still reliable and have great LAN<>WAN through put with the proprietary Broadcom hardware offload)