From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756330AbcG1Rxn (ORCPT ); Thu, 28 Jul 2016 13:53:43 -0400 Received: from down.free-electrons.com ([37.187.137.238]:58182 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752686AbcG1Rxd (ORCPT ); Thu, 28 Jul 2016 13:53:33 -0400 Date: Thu, 28 Jul 2016 19:53:30 +0200 From: Maxime Ripard To: stefan.mavrodiev@gmail.com Cc: dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@armlinux.org.uk, wens@csie.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-sunxi@googlegroups.com Subject: Re: [PATCH v4] ARM: dts: sun8i: Add dts file for Olimex A33-OLinuXino Message-ID: <20160728175330.GC6682@lukather> References: <1469450243-19138-1-git-send-email-stefan.mavrodiev@gmail.com> <30014119.IrjfP0xFry@linux-cigu> <20160727062146.GA6560@lukather> <1604486.mrBvLz4HRZ@linux-cigu> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="9Ek0hoCL9XbhcSqy" Content-Disposition: inline In-Reply-To: <1604486.mrBvLz4HRZ@linux-cigu> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --9Ek0hoCL9XbhcSqy Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Jul 27, 2016 at 01:02:41PM +0300, stefan.mavrodiev@gmail.com wrote: > On Wednesday, July 27, 2016 8:21:46 AM EEST Maxime Ripard wrote: > > On Wed, Jul 27, 2016 at 08:12:29AM +0300, stefan.mavrodiev@gmail.com wr= ote: > > > > > +®_dcdc1 { > > > > > + regulator-always-on; > > > > > + regulator-min-microvolt =3D <3300000>; > > > > > + regulator-max-microvolt =3D <3300000>; > > > > > + regulator-name =3D "vcc-dsi"; > > > > > +}; > > > >=20 > > > > What is it used for? Is it really necessary to keep it on at all ti= me? > > >=20 > > > I think so. > > > This is the supply for the MMC. > >=20 > > Then it's poorly named, and you should tie it to the MMC, and remove > > the always-on if it's only used by the mmc. always-on is supposed to > > be for regulators that shouldn't but turned off for the system to stay > > running. Some MMC regulator doesn't fit that description. > > It's named upon the A33 power pin - "VCC-DSI". Usually, it's based on the name of the output in the schematics, precisely because, from one board to another, it might have different usage. > If I remove "always-on" the board still will work, since dcdc1 is tied to= =20 > mmc0.=20 > vmmc-supply =3D <®_dcdc1>; >=20 > We assume this voltage will be always present and there are some pullups = that=20 > are tied to it (on i2c0 and i2c1 bus). In this case should I remove "alw= ays- > on" from the regulator node? No, you should just tie that regulator to the i2c buses as well. Maxime --=20 Maxime Ripard, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com --9Ek0hoCL9XbhcSqy Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAEBAgAGBQJXmkaaAAoJEBx+YmzsjxAgraAP/RjpIZLQRYbZjuFd4F6EHlTJ dsyNnOi2eYZCIz3Dc6Fe6l/C6+pK/olM51MzJ7MzcIMhSbYFaLxVwiTl7elxnxQR FHHt/OgHUrQ6PXMJvhp64TLbvlgVEv3VXImomzOvXDqzlXlU5w5urHDh7xVAXTL7 iPk18jomykUtgH6/g1JHIqBQgYeY4KQCaznhVA+a9RGE3yIyLkzPgjTjN6/+AX4y CnZs8+hKhABBBYISUJt++U2aTBz1wOIWxjT5E+zuRAu+o4spGvq9eQlTXNEwI19X ay4PZun4l7ATqd3gFhlg2nCVIoEUT36yG+OllrFkTgMC1iXdz/KP236fdbsSHTEn UQP7yUoa7SKaEUPbMlgqeevdd7q8lluqTWEjNbcDfDDCWM4kWK1AvPZBJTTW/CsZ wVBYLF2K1O0kdiyCChoo2FTkntwI77/Hz9JHjZnwRw+Vs64Dwafn/GuCT/77hAg1 vYskal2nwo/zw7kT2HvdjWoiw8/JXEGY12BUhTNG/m7QB8+c2fWYX7LZ9u7SsKPn 63YYixUIwb1iMCZP/54/6Q6qzhIg5w2QxijYTku2cxNPrRJ1v+YgHhOMdNvppyxs snBvQTMByjSTkzIRveNhPr30Lz9UC7iKVs+h9TTlg5zs87OQe1lXMC1xKw14BWtk 4rwUYMrd7YfCNBtb01VT =JohI -----END PGP SIGNATURE----- --9Ek0hoCL9XbhcSqy--