RE: [PATCH] mac80211: Fix sw connection monitor and sw scan when STA is connected HE

[Pkshih <pkshih@realtek.com>]

> -----Original Message-----
> From: Ping-Ke Shih [mailto:pkshih@realtek.com]
> Sent: Friday, June 11, 2021 11:04 AM
> To: johannes@sipsolutions.net
> Cc: linux-wireless@vger.kernel.org
> Subject: [PATCH] mac80211: Fix sw connection monitor and sw scan when STA is connected HE
> 
> Add HE_NULLFUNC_STACK hw_flag to allow sending nullfunc when STA is
> connected HE. Then, sw connection monitor can detects AP has left, and sw
> scan can issue nullfunc properly when switching to off channel.
> 
> The related commits are commit 41cbb0f5a295 ("mac80211: add support for HE")
> that stops sending nullfunc when STA is connected HE, and commit f39b07fdfb68
> ("mac80211: HE STA disassoc due to QOS NULL not sent") that makes STA
> doesn't disconnect locally even if AP has left.
> 
> Signed-off-by: Ping-Ke Shih <pkshih@realtek.com>
> ---
[...]

Hi mac80211 team,

We are working on Realtek 11ax driver, rtw89, not being merged yet.
This driver uses software connection monitor and software scan, like our 11ac driver rtw88,
but we found these two functions don't work properly due to mac80211 doesn't send
null data frame when STA is connected HE.

We search for the reason why it can't send null frame, but we don't get the answer.
Possibly, it is because existing HE hardware supports hardware connection monitor
and scan, or supports TWT to avoid sending null data frame to tell AP its PS mode.
Could anyone enlighten me the reason?

Thank you
--
Ping-Ke