From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964998AbbCXRFo (ORCPT ); Tue, 24 Mar 2015 13:05:44 -0400 Received: from mezzanine.sirena.org.uk ([106.187.55.193]:59283 "EHLO mezzanine.sirena.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S964979AbbCXRF2 (ORCPT ); Tue, 24 Mar 2015 13:05:28 -0400 Date: Tue, 24 Mar 2015 10:05:54 -0700 From: Mark Brown To: Charles Keepax Cc: lgirdwood@gmail.com, linux-kernel@vger.kernel.org, patches@opensource.wolfsonmicro.com Message-ID: <20150324170554.GP17265@sirena.org.uk> References: <1427207276-28038-1-git-send-email-ckeepax@opensource.wolfsonmicro.com> <20150324160609.GD17265@sirena.org.uk> <20150324164050.GI23705@opensource.wolfsonmicro.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="i0LFOk513GRb+T2w" Content-Disposition: inline In-Reply-To: <20150324164050.GI23705@opensource.wolfsonmicro.com> X-Cookie: A good memory does not equal pale ink. User-Agent: Mutt/1.5.23 (2014-03-12) X-SA-Exim-Connect-IP: 12.104.145.3 X-SA-Exim-Mail-From: broonie@sirena.org.uk Subject: Re: [PATCH] regulator: arizona-ldo1: Add ramp time for HI_PWR 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 --i0LFOk513GRb+T2w Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Tue, Mar 24, 2015 at 04:40:50PM +0000, Charles Keepax wrote: > On Tue, Mar 24, 2015 at 09:06:09AM -0700, Mark Brown wrote: > > So changes to move to the top voltage always take constant time while > > all other voltage changes are instantaneous? That doesn't seem right. > > I'd expect something more like a calculation based on some number of > > miliseconds per milivolt. > Its more just that this is the only case that we really care > about. The reg only ever gets used at 1.2V and 1.8V, and the > only case where there is a problem is if we ask for 1.8V and > we don't have it yet. > I don't think we really have the data to give for other cases. I > could expand the comment perhaps? Or TBH it is fast enough it is > unlikely to ever be a problem in practice so we could just drop > the patch. You'll probably find that the ramp is pretty much linear so just changing to something that multiplies out to the expected value will be good enough. I'd rather not have bad examples that other drivers might copy. --i0LFOk513GRb+T2w Content-Type: application/pgp-signature; name="signature.asc" Content-Description: Digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJVEZltAAoJECTWi3JdVIfQQ8EIAIQ77oEOfPUK4BbR2wTjwzGy xVD+Ar4EMKtlF1WgYqJQuhMpbNXXKMIyQCVctylW8qMZOcqySaBPXIHFiQ69ZEps U69BKoC4lk4HFKHoE948uRweu/WzmDCwD9n+OPzCytPZpMhbKq6tVa2jJI0frzpJ JzOBhMFZ4ii1wv81soEu5uMmjaE03Pl45hq7QJ7KyzPSw3uWOd+mU/pRSIZfRcMf 4ec/dUDfsJX1dJIVBRvSS0lu+5gmalcUzPFDq/a67CZp7gsoKkYRQQRI2ZKIa7Na qvCIB48mODs2S6i2tYRqPiU8ruLm3RzsNpeSDfMgALLAVpsmR2W5ySsLSLPq9cE= =uF1E -----END PGP SIGNATURE----- --i0LFOk513GRb+T2w--