Date:   Tue, 29 Jan 2019 13:40:57 +0100
From:   Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
To:     Kalle Valo <kvalo@codeaurora.org>
Cc:     Felix Fietkau <nbd@nbd.name>,
        Stanislaw Gruszka <sgruszka@redhat.com>,
        linux-wireless@vger.kernel.org
Subject: Re: [PATCH v2 0/7] mt76x02: Beacon support for USB
Message-ID: <20190129124056.GB2460@localhost.localdomain>
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> Felix Fietkau <nbd@nbd.name> writes:
> 
> > On 2019-01-29 13:07, Kalle Valo wrote:
> >> Felix Fietkau <nbd@nbd.name> writes:
> >> 
> >>> On 2019-01-29 12:47, Kalle Valo wrote:
> >>>> Stanislaw Gruszka <sgruszka@redhat.com> writes:
> >>>> 
> >>>>> We can configure beaconing, but without TBTT interrupt we
> >>>>> can not support PS buffering. This can be added later using
> >>>>> kernel hrtimer, if we can keep it in sycn with device timer.
> >>>>>
> >>>>> I tested AP and IBSS modes.
> >>>> 
> >>>> So how does this work reliably so that there's no packet loss with
> >>>> clients using power save?
> >>>
> >>> There will be multicast packet loss for clients using power save.
> >> 
> >> Isn't that a problem? At least as a normal user I would very frustrated
> >> if sometimes my connection work and sometimes not, for example if I'm
> >> trying discover devices from my network. Hopefully nobody won't use USB
> >> devices for any real AP stuff, but still enabling something which we
> >> know doesn't work realiably is concerning.
> >
> > I agree. Maybe we should leave out the flag for AP mode in this patch
> > until we have PS buffering and leave the rest of the code intact.
> 
> At least for me that sounds good.

We can support ps buffering in AP as well using a hrtimer. In this way we
can reuse most of the existing code

Regards,
Lorenzo

> 
> -- 
> Kalle Valo