Re: [PATCH v2 0/3] wifi: rtw88: USB fixes

From: Andreas Henriksson
Date: Fri Feb 10 2023 - 13:36:57 EST


Hello Sacha Hauer,

Thanks alot for fixing this!

On Fri, Feb 10, 2023 at 12:16:29PM +0100, Sascha Hauer wrote:
> This series addresses issues for the recently added RTW88 USB support
> reported by Andreas Henriksson and also our customer.
>
> The hardware can't handle urbs that have a size of multiple of the
> bulkout_size (usually 512 bytes). The symptom is that the hardware
> stalls completely. The issue can be reproduced by sending a suitably
> sized ping packet from the device:
>
> ping -s 394 <somehost>
>
> (It's 394 bytes here on a RTL8822CU and RTL8821CU, the actual size may
> differ on other chips, it was 402 bytes on a RTL8723DU)

I can confirm that with these patches applied that my LM842 dongle
now works reliably on my imx6sx board. On the same board the traffic
would previously usually stall after 80-130MB when downloading.

With patches applied I succesfully completed:
wget -O /dev/null http://speedtest.tele2.net/10GB.zip

Uploading did not seem to trigger the problem before but I still
tested and uploading a gigabyte was no problem using:
curl -T /dev/urandom http://speedtest.tele2.net/upload.php -O /dev/null

Did not attempt the suggested ping method of reproducing on the old
system, but on the new kernel I could do
$ for a in $(seq 128 512); do ping -n -c 3 -s $a ping.sunet.se ; done
without any stalls.


Feel free to add either or both of:

Reported-by: Andreas Henriksson <andreas@xxxxxxxx>
Tested-by: Andreas Henriksson <andreas@xxxxxxxx>

>
> Other than that qsel was not set correctly. The sympton here is that
> only one of multiple bulk endpoints was used to send data.
>
> Changes since v1:
> - Use URB_ZERO_PACKET to let the USB host controller handle it automatically
> rather than working around the issue.
>
> Sascha Hauer (3):
> wifi: rtw88: usb: Set qsel correctly
> wifi: rtw88: usb: send Zero length packets if necessary
> wifi: rtw88: usb: drop now unnecessary URB size check
>
> drivers/net/wireless/realtek/rtw88/usb.c | 18 +++---------------
> 1 file changed, 3 insertions(+), 15 deletions(-)
>
> --
> 2.30.2
>

Regards,
Andreas Henriksson