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Subject: Re: rtlwifi/rtl8192cu AP mode broken with PS STA
From:   "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>
To:     Ping-Ke Shih <pkshih@realtek.com>
Cc:     Johannes Berg <johannes@sipsolutions.net>,
        linux-wireless@vger.kernel.org, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, Kalle Valo <kvalo@codeaurora.org>,
        Larry Finger <Larry.Finger@lwfinger.net>
References: <e2924d81-0e30-2dd0-292b-428fea199484@maciej.szmigiero.name>
Message-ID: <846f6166-c570-01fc-6bbc-3e3b44e51327@maciej.szmigiero.name>
Date:   Sun, 4 Apr 2021 20:06:06 +0200
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On 29.03.2021 00:54, Maciej S. Szmigiero wrote:
> Hi,
> 
> It looks like rtlwifi/rtl8192cu AP mode is broken when a STA is using PS,
> since the driver does not update its beacon to account for TIM changes,
> so a station that is sleeping will never learn that it has packets
> buffered at the AP.
> 
> Looking at the code, the rtl8192cu driver implements neither the set_tim()
> callback, nor does it explicitly update beacon data periodically, so it
> has no way to learn that it had changed.
> 
> This results in the AP mode being virtually unusable with STAs that do
> PS and don't allow for it to be disabled (IoT devices, mobile phones,
> etc.).
> 
> I think the easiest fix here would be to implement set_tim() for example
> the way rt2x00 driver does: queue a work or schedule a tasklet to update
> the beacon data on the device.

Are there any plans to fix this?
The driver is listed as maintained by Ping-Ke.

Thanks,
Maciej