From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933430AbbCQKjk (ORCPT ); Tue, 17 Mar 2015 06:39:40 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:49032 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932217AbbCQKjg (ORCPT ); Tue, 17 Mar 2015 06:39:36 -0400 Date: Tue, 17 Mar 2015 10:38:29 +0000 From: Mark Brown To: Ulf Hansson Cc: Doug Anderson , Heiko Stuebner , Jaehoon Chung , Seungwon Jeon , Alexandru Stan , Alim Akhtar , Sonny Rao , Andrew Bresticker , Addy Ke , Javier Martinez Canillas , "open list:ARM/Rockchip SoC..." , "linux-arm-kernel@lists.infradead.org" , Chris Ball , Johan Rudholm , Adrian Hunter , Tim Kryger , Andrew Gabbasov , Sascha Hauer , linux-mmc , "linux-kernel@vger.kernel.org" Message-ID: <20150317103829.GA28806@sirena.org.uk> References: <1426112117-18220-1-git-send-email-dianders@chromium.org> <1426112117-18220-2-git-send-email-dianders@chromium.org> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="Eo6Jsvut/kxSJJ94" Content-Disposition: inline In-Reply-To: X-Cookie: Editing is a rewording activity. User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: 94.175.94.161 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH v4 2/4] mmc: core: Add mmc_regulator_set_vqmmc() X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on mezzanine.sirena.org.uk) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --Eo6Jsvut/kxSJJ94 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Mar 17, 2015 at 11:23:33AM +0100, Ulf Hansson wrote: > On 16 March 2015 at 16:12, Doug Anderson wrote: > > * Try to set the voltage to exactly 1,200,000 uV (1.2V). > > * If you can't get 1.2V exactly, a tolerance ("tol") of 100,000 uV > > (.1V) is OK. > > * In other words, 1.1V - 1.3V are OK, but aim for 1.2V > So what happens in the case when 1.3V and 1.1V, but not 1.2V. Which > value will be used? Is that algorithm defined by the regulator core or > does it depend per regulator implementation? It's done in the core. It first tries to hit the target voltage to the maximum (picking the lowest voltage in that range) then tries to pick the lowest voltage to the target, though that's an implementation detail and we really should be trying to get as close as possible to the target. We don't do that yet because it can be expensive to work out so we do the current thing which is cheap and mostly good enough. --Eo6Jsvut/kxSJJ94 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJVCAQlAAoJECTWi3JdVIfQ0VYH/iZeQc/hihsEyP2+K+a9Gs7R JSVKhWCEk+XDG5aQELFL0ZrWGqlYqA/2ChT2vuWowjKNB8F7ygAMQffeJSozoH25 G2H0OU3vV4xPQCe8NWPLAbRjrj/wbJ7b96okb7twTIZ41qk3Wi6wXzrTdwKmrxqH +IxpL2EfJQDoaJcLrC3wcDCfRMFq6wzFwswf7fB+Z3tlLVQB8MFH/5YmAOvL6/dj s3c9/KErYeBe9Zy0AJhzuJbwAoLKfsIAHLOMs8tdGdZFEWIjhin7MumA2RY57SCm wTnvtBM8XH39SAnRyIugSriSGstNpvIZAcuVEBWwwGoEhzCSqB805RdshtuHFYM= =9NOH -----END PGP SIGNATURE----- --Eo6Jsvut/kxSJJ94--