Return-Path: Date: Sun, 27 Aug 2017 12:40:30 +0200 (CEST) From: Stefan Wahren To: Marcel Holtmann Cc: Ray Jui , Scott Branden , Rob Herring , Maxime Ripard , Loic Poulain , f.fainelli@gmail.com, linux-rpi-kernel@lists.infradead.org, "open list:BLUETOOTH DRIVERS" , Johan Hedberg , devicetree@vger.kernel.org Message-ID: <1169267908.44062.1503830430635@email.1und1.de> In-Reply-To: References: <1501576704-26423-1-git-send-email-loic.poulain@gmail.com> <20170822074726.e424lflqxn6mb4xd@flea.lan> <4c23bcb6-1b90-c41e-6e47-7d8315e760ae@gmail.com> <9BD5C644-6B89-496C-B442-F276D7A99102@holtmann.org> <123116901.43777.1503827664160@email.1und1.de> Subject: Re: [PATCH v2 1/3] dt-bindings: net: bluetooth: Add broadcom-bluetooth MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 List-ID: Hi Marcel, > Marcel Holtmann hat am 27. August 2017 um 12:23 ges= chrieben: >=20 >=20 > Hi Stefan, >=20 > >>>>> Thanks a lot for working on that, I've made a similar attempt a few > >>>>> weeks ago but didn't manage to get it to work. > >>>>>=20 > >>>>> The way it's hooked in our boards is a bit more complex though, eve= n > >>>>> if it could be because we're using a different part. > >>>>>=20 > >>>>> In order to get it running we need: > >>>>> - two clocks, called in the broadcom datasheets lpo and tcxo. > >>>>> - three GPIOs, device wakeup, host wakeup and a shutdown GPIO (whi= ch > >>>>> might be the BT_ON you were discussing about) > >>>>> - two regulators called vbat and reg-en for us (I guess they're > >>>>> meant to power the chip, and its registers >> > >>>>> Do you know if you're also using those? Or could it be that it's ju= st > >>>>> hardwired to some non-gatable crystal / regulator on the RPI? > >>>=20 > >>> Not on Pi3, but the three gpios and the clock are pretty common for > >>> Broadcom bt controller (cf v4 of dt-bindings patch). > >>=20 > >> once we get the GPIO expander driver upstream, I think we also need th= is for RPI 3 and Zero W. Right now we can just not do anything about this. > >=20 > > AFAIK the Zero W doesn't have this GPIO expander. Would it be easier fo= r you? >=20 > I don=E2=80=99t understand the question. In general you want the BT_ON an= d wakeup GPIOs to be available so that you can have good power savings. If = they are not there, then it is always powered. It works of course as shown = with RPI 3 where the boot loader enables the GPIOs. Which means it is like = the current support that we have in net-next. the question was related to the point that all SoC GPIOs should be directly= connected to the 43438. So using Zero W for development could be easier, b= ecause you don't need the GPIO expander driver. But generally i agree that = it should work with RPI 3.=20 >=20 > On the other hand, the hci_bcm.c support for RPI 3 is essentially a suppo= rt for all Broadcom devices using DT. It should be extended to support all = sorts of boards. And once ACPI becomes serdev support, we can unify ACPI, p= latform and DT devices into a single code path. >=20 > Regards >=20 > Marcel >