2021-01-17 18:14:44

by Alex Dewar

[permalink] [raw]
Subject: How to port rtl8xxxu to new device...?

Hi all,

I'm currently trying to port the rtl8xxxu driver to RTL8822u chips (one
of which I own), but I'm finding it hard to figure out where to start
and I figured that some wiser minds could maybe help steer me in the
right direction.

I've managed to get as far as reading and writing to various registers
as part of the device setup, but the dongle appears to crash at the
downloading firmware stage. At the moment it just feels like I'm
changing random bits and pieces to see what happens. I'm using this
downstream driver for reference: https://github.com/RinCat/RTL88x2BU-Linux-Driver

Does anyone know of any documentation or anything that could be useful
for working on this?

Best,
Alex


2021-01-17 21:02:38

by Geoffrey Mon

[permalink] [raw]
Subject: Re: How to port rtl8xxxu to new device...?

On Sun, Jan 17, 2021 at 05:55:33PM +0000, Alex Dewar wrote:
> Hi all,
>
> I'm currently trying to port the rtl8xxxu driver to RTL8822u chips (one
> of which I own), but I'm finding it hard to figure out where to start
> and I figured that some wiser minds could maybe help steer me in the
> right direction.
>
Hi Alex,

I am not very knowledgeable since I've only just started looking into adding
support for some older Realtek USB adapters, but another starting point for
adding rtl8822bu support might be the rtw88 driver, which is specifically
built for rtl88xx chips and which has support for rtl8822be (which uses PCIe);
in principle a lot of code can be shared between 8822b{e,u}. However, although
rtw88 includes some structure to support USB devices in the future, this support
hasn't been added yet. There is at least one project[0] that I've come across
trying to add that support. I'm not sure how active this project is but it does
look like they have some work in progress for rtl8822bu.

Best,
Geoffrey

[0] https://github.com/ulli-kroll/rtw88-usb

2021-01-17 21:11:23

by Alex Dewar

[permalink] [raw]
Subject: Re: How to port rtl8xxxu to new device...?

On Sun, Jan 17, 2021 at 02:14:34PM -0500, Geoffrey Mon wrote:
> On Sun, Jan 17, 2021 at 05:55:33PM +0000, Alex Dewar wrote:
> > Hi all,
> >
> > I'm currently trying to port the rtl8xxxu driver to RTL8822u chips (one
> > of which I own), but I'm finding it hard to figure out where to start
> > and I figured that some wiser minds could maybe help steer me in the
> > right direction.
> >
> Hi Alex,
>
> I am not very knowledgeable since I've only just started looking into adding
> support for some older Realtek USB adapters, but another starting point for
> adding rtl8822bu support might be the rtw88 driver, which is specifically
> built for rtl88xx chips and which has support for rtl8822be (which uses PCIe);
> in principle a lot of code can be shared between 8822b{e,u}. However, although
> rtw88 includes some structure to support USB devices in the future, this support
> hasn't been added yet. There is at least one project[0] that I've come across
> trying to add that support. I'm not sure how active this project is but it does
> look like they have some work in progress for rtl8822bu.

This was really helpful. Thanks!

The project seems somewhat up to date (although I did get a hard lockup
when I tried to use it...), but it definitely seems a useful avenue to
go down.

Best,
Alex

>
> Best,
> Geoffrey
>
> [0] https://github.com/ulli-kroll/rtw88-usb