Alfa AWUS036ACM (Mediatek MT7612U) AP problem

Alfa AWUS036ACM (Mediatek MT7612U) AP problem

[James]

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?

Re: Alfa AWUS036ACM (Mediatek MT7612U) AP problem

[Mathy Vanhoef]

I have similar issues with an AWUS036ACM when connected to a USB3.0
port. When connected to a USB2.0 port it seems to work fine.

In particular, on both kernel 5.5.0 and 5.6.13 on a USB3.0 port when
running an AP I get the error "mt76x2u: error: mt76x02u_mcu_wait_resp
failed with -108". On the same kernels but using a USB2.0 port the AP
seems to work properly.

On Fri, Jun 26, 2020 at 11:33 PM James <bjlockie@lockie.ca> wrote:
>
> 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?
>

Re: Alfa AWUS036ACM (Mediatek MT7612U) AP problem

[James]

Kernel 5.4.48 is better so far:
Uptime
1d 18h 6m 32s
It sounds like it is only a matter of time since you have the problem on 
a later kernel.
I did get rid of a cable and use a powered USB 3 hub.

Re: Alfa AWUS036ACM (Mediatek MT7612U) AP problem

[Lorenzo Bianconi]

[-- Attachment #1: Type: text/plain, Size: 297 bytes --]

> Kernel 5.4.48 is better so far:
> Uptime
> 1d 18h 6m 32s
> It sounds like it is only a matter of time since you have the problem on a
> later kernel.
> I did get rid of a cable and use a powered USB 3 hub.

Can you please try to load the mt76_usb module with disable_usb_sg=1?

Regards,
Lorenzo

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Re: Alfa AWUS036ACM (Mediatek MT7612U) AP problem

[James]

On 2020-06-29 5:19 a.m., Lorenzo Bianconi wrote:
>> Kernel 5.4.48 is better so far:
>> Uptime
>> 1d 18h 6m 32s
>> It sounds like it is only a matter of time since you have the problem on a
>> later kernel.
>> I did get rid of a cable and use a powered USB 3 hub.
> Can you please try to load the mt76_usb module with disable_usb_sg=1?
>
> Regards,
> Lorenzo
It just died, Uptime 2d 14h 23m 22s. :-(

Shouldn't modinfo list the available parameters?
# modinfo mt76_usb
module:         /lib/modules/5.4.48/mt76-usb.ko
license:        Dual BSD/GPL
depends:        mt76,mac80211
name:           mt76_usb
vermagic:       5.4.48 SMP mod_unload aarch64

# ls /sys/module/mt76_usb/parameters/
disable_usb_sg


# cat /sys/module/mt76_usb/parameters/disable_usb_sg
N

I've tried a few things in /etc/module.d but nothing worked yet.
I unplugged the dongle and did:
# echo 1 > /sys/module/mt76_usb/parameters/disable_usb_sg
I plugged in the dongle:
# cat /sys/module/mt76_usb/parameters/disable_usb_sg
Y

I found this old post that helped:
https://github.com/openwrt/mt76/issues/398

disable_usb_sg=1

[James]

On 2020-06-29 5:19 a.m., Lorenzo Bianconi wrote:
>> Kernel 5.4.48 is better so far:
>> Uptime
>> 1d 18h 6m 32s
>> It sounds like it is only a matter of time since you have the problem on a
>> later kernel.
>> I did get rid of a cable and use a powered USB 3 hub.
> Can you please try to load the mt76_usb module with disable_usb_sg=1?
>
> Regards,
> Lorenzo
Almost 2 days and no problem after disable_usb_sg=1
https://docs.gz.ro/tuning-network-cards-on-linux.html
 >TCP offload engine
 >Linux doesn't support TOE by default
Why isn't it disabled by default?