From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1032928AbdADWlq (ORCPT ); Wed, 4 Jan 2017 17:41:46 -0500 Received: from mail-wm0-f68.google.com ([74.125.82.68]:33613 "EHLO mail-wm0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1032539AbdADWll (ORCPT ); Wed, 4 Jan 2017 17:41:41 -0500 From: Pali =?utf-8?q?Roh=C3=A1r?= To: Aaro Koskinen Subject: Re: Nokia N900 sound driver and ECI GPIOs Date: Wed, 4 Jan 2017 23:41:37 +0100 User-Agent: KMail/1.13.7 (Linux/4.9.0-040900-generic; KDE/4.14.2; x86_64; ; ) Cc: joerg Reisenweber , Peter Ujfalusi , Jarkko Nikula , Tony Lindgren , Eduardo Valentin , "Lars-Peter Clausen" , Nishanth Menon , Sebastian Reichel , Pavel Machek , Ivaylo Dimitrov , linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org References: <201701012054.54505@pali> <2036063.jAbaHqGlp2@saturn> <20170104222749.4xmyws6zcifeicz5@raspberrypi-2.musicnaut.iki.fi> In-Reply-To: <20170104222749.4xmyws6zcifeicz5@raspberrypi-2.musicnaut.iki.fi> MIME-Version: 1.0 Content-Type: multipart/signed; boundary="nextPart8948303.7JE7sSu3do"; protocol="application/pgp-signature"; micalg=pgp-sha1 Content-Transfer-Encoding: 7bit Message-Id: <201701042341.37944@pali> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --nextPart8948303.7JE7sSu3do Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable On Wednesday 04 January 2017 23:27:49 Aaro Koskinen wrote: > Hi, >=20 > On Mon, Jan 02, 2017 at 10:05:39PM +0100, joerg Reisenweber wrote: > > On Mon 02 January 2017 21:01:01 Pali Roh=C3=A1r wrote: > > > On Monday 02 January 2017 19:49:45 Aaro Koskinen wrote: > > > > The schematic shows ECI(5:0), but only 3 are connected/used. > > > > There were 3 other GPIOs reserved but not used in the final > > > > product. > > >=20 > > > Are you sure that this is truth (maybe you have some > > > information)? Or you just looked at schematic and deduced this > > > observation (as other people too)? > > >=20 > > > Joerg already told us that RX51 schematic does not 100% match > > > production N900 and e.g. there is missing UART3 pins... > >=20 > > We found this, see https://irclog.whitequark.org/neo900/2017-01-01 > > (has a lot of possibly useful references/links) > > The question is if pin AA3 aka GPIO_178 is actually NotConnected in > > N900 or it's just an omission in schematics and there's actually > > some more 'stealth hardware' in N900 that doesn't show up in docs, > > just like the testpoint UART console > > http://wiki.maemo.org/N900_Hardware_Hacking#Debug_ports which also > > are missing in schematics. > >=20 > > > What we know that gpio 178 is *already* controlled and changed by > > > production Nokia kernel running on production N900 devices (as I > > > wrote in first email). > >=20 > > I could use one of the unpopulated N900 PCB and solder a wire to > > the OMAP AA3 pad, then try to make sure it's not connected to > > anything, or if it is then find out about the details of this. > > But I'm reluctant to do this, since it's an error prone and (in > > case of N/C) not verifiable procedure, so I'd appreciate any > > further info, whether from historical anecdote or from sourcecode > > review and conclusions, regarding that. >=20 > Even if the published production kernel source controls GPIO 178, it > does not mean the production device has it connected, as the same > kernel also supported many older in-house prototype versions of the > hardware (and some of those had it connected). Yes, seems reasonable. Also in production kernel source there is on some=20 places check for prototype hw revision and acts differently... > Probably the easiest test would be to take the final published > source, and then comment out all the GPIO 178 related code and build > and run the kernel on the production device. Then see if you can > observe any difference in behaviour. Current mainline kernel does not control GPIO 178, so looks like audio=20 somehow working... Jarkko sent driver to mainline so I asked in this=20 thread if does not know something... But A/V cable detection is not in=20 mainline (yet). We can do that test to verify if production Maemo system is working as=20 before. But result "nothing visible" does not prove that GPIO does not=20 control anything. With this test we can just prove if system stops=20 working as before. =2D-=20 Pali Roh=C3=A1r pali.rohar@gmail.com --nextPart8948303.7JE7sSu3do Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iEYEABECAAYFAlhteiEACgkQi/DJPQPkQ1LN2ACgzG5erLDHS226n7TyCAQ8Ed12 UYAAnijKbbPynxDvRfvYORVn9z1y/wRz =ivmS -----END PGP SIGNATURE----- --nextPart8948303.7JE7sSu3do--