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From:   James <bjlockie@lockie.ca>
Subject: Alfa AWUS036ACM (Mediatek MT7612U) AP problem
To:     linux-wireless@vger.kernel.org
Message-ID: <ba64416e-d34b-9bdd-d482-6ea722e3d6b9@lockie.ca>
Date:   Fri, 26 Jun 2020 15:32:47 -0400
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I have an Alfa AWUS036ACM (Mediatek MT7612U).
My AP keeps dieing.
The error:
mt76x2u: error: mt76x02u_mcu_wait_resp failed with -110
seems to be common.

I use it with a build of a OpenWrt on a Raspberry Pi 4 (Broadcom BCM2711 
SoC, ARM Cortex-A72 processor (64bit)).
Linux OpenWrt 5.4.48 #0 SMP Thu Jun 25 00:36:19 2020 aarch64 GNU/Linux
Loading modules backported from Linux version v5.7-rc3-0-g6a8b55ed4056

# lsmod | grep mt76
cfg80211              339968  5 
mt76x02_usb,mt76x02_lib,mt7603e,mt76,mac80211
mac80211              589824  7 
mt76x2u,mt76x2e,mt76x02_usb,mt76x02_lib,mt7603e,mt76_usb,mt76
mt76                   45056  7 
mt76x2u,mt76x2e,mt76x2_common,mt76x02_usb,mt76x02_lib,mt7603e,mt76_usb
mt76_usb               24576  2 mt76x2u,mt76x02_usb
mt7603e                53248  0
mt76x02_lib            61440  4 mt76x2u,mt76x2e,mt76x2_common,mt76x02_usb
mt76x02_usb            20480  1 mt76x2u
mt76x2_common          20480  2 mt76x2u,mt76x2e
mt76x2e                20480  0
mt76x2u                20480  0

I bought a powered USB3 hub and removed a USB3 cable in case that is 
related but the problem is still there.

I've been documenting my problems:
https://github.com/openwrt/mt76/issues/405#
Are any of the tracebacks useful?

I found this:
https://github.com/openwrt/mt76/issues/403
>
>
>       *LorenzoBianconi *commented on May 10
>
> @petrkalosthis conditions is used to reset the device in case of 
> necessary (it is in the vendor sdk). You can try to comment it out and 
> see what happen
>
I downloaded 
https://d86o2zu8ugzlg.cloudfront.net/mediatek-craft/drivers/MT7612U_DPO_LinuxSTA_3.0.0.1_20140718.tar.bz2
and there is no "mcu_wait_resp".

I also found this:
https://github.com/raspberrypi/linux/issues/3014


What 80211.ac USB adapter has the best (most open and compatible) now 
(or likely) linux kernel support?