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From: Doug Anderson <dianders@chromium.org>
Date: Thu, 25 Apr 2024 23:22:50 +0800
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Subject: Re: [PATCH] Bluetooth: qca: fix invalid device address check
To: Johan Hovold <johan@kernel.org>
Cc: Janaki Ramaiah Thota <quic_janathot@quicinc.com>, Johan Hovold <johan+linaro@kernel.org>, 
	Marcel Holtmann <marcel@holtmann.org>, Luiz Augusto von Dentz <luiz.dentz@gmail.com>, 
	Matthias Kaehlcke <mka@chromium.org>, linux-bluetooth@vger.kernel.org, 
	linux-kernel@vger.kernel.org, stable@vger.kernel.org, 
	Stephen Boyd <swboyd@chromium.org>
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Hi,

On Thu, Apr 25, 2024 at 4:40=E2=80=AFPM Johan Hovold <johan@kernel.org> wro=
te:
>
> > > I assume all Trogdor boards use the same controller, WCN3991 IIUC, bu=
t
> > > if you're worried about there being devices out there using a differe=
nt
> > > address we could possibly also use the new
> > > "qcom,local-bd-address-broken" DT property as an indicator to set the
> > > bdaddr quirk.
> >
> > They all should use the same controller, but I'm just worried because
> > I don't personally know anything about how this address gets
> > programmed nor if there is any guarantee from Qualcomm that it'll be
> > consistent. There are a whole pile of boards in the field, so unless
> > we have some certainty that they all have the same address it feels
> > risky.
>
> Hopefully Janaki and Qualcomm will provide some answers soon.
>
> And otherwise we have another fall back in that we can use the
> "qcom,local-bd-address-broken" property for Trogdor.

Quick question. I haven't spent lots of time digging into the
Bluetooth subsystem, but it seems like if the device tree property is
there it should take precedence anyway, shouldn't it? In other words:
if we think there is built-in storage for the MAC address but we also
see a device tree property then we need to decide which of the two we
are going to use. Are there any instances where there's a bogus DT
property and we want the built-in storage to override it?

-Doug