2017-11-20 16:39:48

by James Hughes

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Subject: Question on a RTL8812AU driver

Hello all,

I know there been a lot of work done on Realtek drivers in the last
few months, and was wondering whether this will be of use for my
particular issue.

We have a Raspberry Pi that needs to use a USB wireless adaptor
(2001:3314) which uses the rtl8812AU chipset. We have to use this
device as it's the only one that has been qualified for this
particular use case.

We have been using an out of tree driver, I think originally from
Realtek, that works, but after a few days locks up, and often requires
a reboot on the Pi. We do have some mitigation strategies, but it'
would be better to have a working driver. The Pi is, on the whole,
inaccessible.

The OoT driver is from here
https://github.com/diederikdehaas/rtl8812AU and appear quite ancient.

So, I've been looking at the 4.14 staging drivers that do seem to have
support for some realtek devices. However, none of the drivers I have
built recognise the module. The source of rtlwifi does refer to the
8812AU, but only to ignore it. There are other references throughout
the source.,

My question, eventually, is down to figuring out whether any of the
new staging code is destined to work on this device, or am I going to
have to stick with the driver we are currently using which clearly has
a lockup issue that I, in all likelihood, not going to be able to
track down since its takes days for it to occur.

Or if anyone has any suggestions for getting this working, I'm all ears.

TIA

James Hughes, Raspberry Pi.


2017-11-20 17:13:55

by Larry Finger

[permalink] [raw]
Subject: Re: Question on a RTL8812AU driver

On 11/20/2017 10:39 AM, James Hughes wrote:
> Hello all,
>
> I know there been a lot of work done on Realtek drivers in the last
> few months, and was wondering whether this will be of use for my
> particular issue.
>
> We have a Raspberry Pi that needs to use a USB wireless adaptor
> (2001:3314) which uses the rtl8812AU chipset. We have to use this
> device as it's the only one that has been qualified for this
> particular use case.
>
> We have been using an out of tree driver, I think originally from
> Realtek, that works, but after a few days locks up, and often requires
> a reboot on the Pi. We do have some mitigation strategies, but it'
> would be better to have a working driver. The Pi is, on the whole,
> inaccessible.
>
> The OoT driver is from here
> https://github.com/diederikdehaas/rtl8812AU and appear quite ancient.
>
> So, I've been looking at the 4.14 staging drivers that do seem to have
> support for some realtek devices. However, none of the drivers I have
> built recognise the module. The source of rtlwifi does refer to the
> 8812AU, but only to ignore it. There are other references throughout
> the source.,
>
> My question, eventually, is down to figuring out whether any of the
> new staging code is destined to work on this device, or am I going to
> have to stick with the driver we are currently using which clearly has
> a lockup issue that I, in all likelihood, not going to be able to
> track down since its takes days for it to occur.
>
> Or if anyone has any suggestions for getting this working, I'm all ears.

To my knowledge, there are no plans to convert the buggy, and badly written,
code for the RTL8812AU into a form that would be suitable for wireless. Even
getting it into a form that would be acceptable for staging would be a
formidable task.

If you want this device supported by an in-kernel driver, the easiest method
would be to extend rtl8xxxu. Jes Sorensen, the author of that driver, might be
able to help you with that extension.

I know nothing of that "diederikdehaas" repo; however, I have a separate one at
https://github.com/lwfinger/rtl8812au that I keep up to date. Note that I do not
have such a device. The repo is just for convenience.

Larry