ALFA AWUS036ACM MT7612U not work in AC mode on router GL-AR750S

ALFA AWUS036ACM MT7612U not work in AC mode on router GL-AR750S

ROUTER:
GL.iNet GL-AR750S (NOR/NAND)
Qualcomm Atheros QCA956X ver 1 rev 0
ath79/nand
OpenWrt 22.03.3 r20028-43d71ad93e / LuCI openwrt-22.03 branch git-23.039.29681-007c243

CLIENT:
ALFA AWUS036ACM
WiFi USB MT7612U mt76x2u linux module

LINUX:
Linux manjaro 6.1.12-1-MANJARO

PROBLEM:
Not IP in AC mode. Connection refused in NetworkManager without IP after about 15 seconds.
Works in N mode in any band.
AC mode works perfect to others clients ... rtl-8812au, rtl-8821cu ...

Any ideas to make it work ALFA AWUS036ACM WiFi USB MT7612U in AC mode on GL.iNet GL-AR750S?

Thanks in advance.

The same adapter works fine with Linksys E8450 in AC mode. The client is running Arch Linux. Here is my 5 GHz WiFi config in /etc/config/wireless:

config wifi-device 'radio1'
	option type 'mac80211'
	option path '1a143000.pcie/pci0000:00/0000:00:00.0/0000:01:00.0'
	option band '5g'
	option country 'PH'
	option cell_density '2'
	option local_pwr_constraint '0'
	option he_bss_color '53'
	option log_level '1'
	option htmode 'HE80'
	option channel '52'

config wifi-iface 'wifinet2'
	option device 'radio0'
	option mode 'ap'
	option ssid 'Archer'
	option key 'PASSWORDhidden!'
	option wpa_disable_eapol_key_retries '1'
	option network 'lan'
	option wds '1'
	option encryption 'sae-mixed'
	option wnm_sleep_mode '1'
	option bss_transition '1'
	option ieee80211k '1'
	option ieee80211r '1'
	option mobility_domain '8ac0'
	option ft_over_ds '1'
	option ft_psk_generate_local '0'
	option pmk_r1_push '1'

Yes it does contain some options from the failed band-steering/roaming experiment, please ignore them.

Hello. Thanks for answering.

I have another router based on rockchip/armv8 and running OpenWrt 22.03.3 (FriendlyElec) and the ALFA adapter connects in AC mode without problems and gives good speeds.
The problem seems to be between the mt76x2u linux driver and the ath79/nand router platform Qualcomm Atheros QCA956X ver 1 rev 0.
I've tried everything from using iwd instead of wpa_supplicant on linux, to switching from dhcpcd to dhclient, to trying the router radio without encryption, to trying different channels and no way to get it to connect in AC mode.
N mode works smoothly on both 2.4 and 5GHz.

My wifi setup is very simple and all the other adapters I have 8812au, 8821cu dual band connect to the router in AC mode with the same configuration without problems.

Like a note I am using...

ath10k-board-qca9887
ath10k-firmware-qca9887
kmod-ath10k

And scan channels on 5GHz works OK but with default openwrt 22.03 installation...
ath10k-firmware-qca9887-ct
not work scan on 5GHz band , the -ct packages not work properly to scan on 5GHz band (luci and command line) on router GL.iNet GL-AR750S (NOR/NAND) on latest official release openwrt 22.03.