Re: [PATCH 0/3] usb: dwc2: Fixes and improvements

[Doug Anderson]

Hi,

On Wed, Jan 13, 2021 at 3:21 AM Nicolas Saenz Julienne
<nsaenzjulienne@xxxxxxx> wrote:
>
> I'm picking up this series by Guenter Roeck as he stated he has no time
> for it ATM. It was found to solve some unaligned DMA access issues on
> Raspberry Pi 3. You can find the original discussion here:
> https://lore.kernel.org/linux-usb/20200226210414.28133-1-linux@xxxxxxxxxxxx/
>
> I removed the fist patch from the original series as it turned out to be
> contententious and needs more in-depth testing. Following is the edited
> origin series description. Note that extra testing was performed on
> RPi3:
>
> "This series addresses the following problems:
>
> - Fix receive transfers with 0 byte transfer length
> - Abort transactions after unknown receive errors
>   if the receive buffer is full
> - Reduce "trimming xfer length" logging noise
>
> The problems fixed with this series were observed when connecting
> a DM9600 Ethernet adapter to Veyron Chromebooks such as the ASUS
> Chromebook C201PA. The series was tested extensively with this and
> other adapters.
>
> The observed problems are also reported when tethering various
> phones, so test coverage with such phones would be very appreciated."
>
> ---
>
> Guenter Roeck (3):
>   usb: dwc2: Do not update data length if it is 0 on inbound transfers
>   usb: dwc2: Abort transaction after errors with unknown reason
>   usb: dwc2: Make "trimming xfer length" a debug message
>
>  drivers/usb/dwc2/hcd.c      | 15 ++++++++-------
>  drivers/usb/dwc2/hcd_intr.c | 14 +++++++++++++-
>  2 files changed, 21 insertions(+), 8 deletions(-)

It's been long enough ago that I've forgotten where this was left off,
but IIRC the 3 patches that you have here are all fine to land (and
have my Reviewed-by tag).  However, I think Guenter was still tracking
down additional problems.  Guenter: does that match your recollection?

It looks like there are still bugs open for this on our public bug tracker:

https://issuetracker.google.com/issues/172208170
https://issuetracker.google.com/issues/172216241

...but, as Guenter said, I don't think there's anyone actively working on them.

I'm not really doing too much with dwc2 these days either and don't
currently have good HW setup for testing, so for the most part I'll
leave it to you.  I wanted to at least summarize what I remembered,
though!  :-)

-Doug