From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756117Ab1KDWfX (ORCPT ); Fri, 4 Nov 2011 18:35:23 -0400 Received: from opensource.wolfsonmicro.com ([80.75.67.52]:55316 "EHLO opensource.wolfsonmicro.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752973Ab1KDWfW (ORCPT ); Fri, 4 Nov 2011 18:35:22 -0400 Date: Fri, 4 Nov 2011 22:35:19 +0000 From: Mark Brown To: Olof Johansson Cc: Rajendra Nayak , grant.likely@secretlab.ca, patches@linaro.org, tony@atomide.com, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, lrg@ti.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH v4 1/4] regulator: helper routine to extract regulator_init_data Message-ID: <20111104223518.GC16978@opensource.wolfsonmicro.com> References: <1319721864-30067-1-git-send-email-rnayak@ti.com> <20111104202905.GA3918@quad.lixom.net> <20111104211447.GC2541@opensource.wolfsonmicro.com> <20111104212216.GA5756@quad.lixom.net> <20111104212910.GB8266@opensource.wolfsonmicro.com> <20111104214650.GC8266@opensource.wolfsonmicro.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Cookie: You will be misunderstood by everyone. User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 04, 2011 at 03:16:12PM -0700, Olof Johansson wrote: > On Fri, Nov 4, 2011 at 2:46 PM, Mark Brown > >> Describing that in the device tree using regulator-specifiers > >> shouldn't be too bad? The LDO will reference the DCDC as the parent > >> supply (or input or whatever language you prefer). They don't have to > >> be in the same topology, they will instead be under whatever > >> controller/bus they are on for control -- i2c, etc. > > That's not great as it means you've got a separate binding for supplies > > that happen to be connected to another regulator from that used for > > other supplies on the device which is particularly confusing in the > > fairly common case where a regulator chip has multiple supplies.  Using > > the same method for binding all supplies seems much neater. > I'm not following the above 100%, but I think you are saying that you > would prefer to describe the regulator / power hierarchy in the > functional topology instead of how the various regulators and supplies > are organized on i2c busses and other controllers? And the obvious > one that would be less than trivial to find a home for would be the > top-level or freestanding fixed regulators that don't sit on a > controlling bus. No, that's not the issue at all. The issue is that we want a single way of describing the supplies a device has regardless of their function (which is what the existing stuff does). Consider the case of a simple regulator with register control. It is going to have a supply used for the regulator itself and almost certainly also a separate digital buffer supply used to reference the digital I/O. It seems bad to specify the first supply in a different manner to the second, and there are more complex examples where a supply can be both a regulator input and also a more general purpose supply.