From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754254AbbJHIct (ORCPT ); Thu, 8 Oct 2015 04:32:49 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37524 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753857AbbJHIcp (ORCPT ); Thu, 8 Oct 2015 04:32:45 -0400 Subject: Re: [linux-sunxi] Re: [PATCH v2] ARM: dts: sunxi: Add regulators for LeMaker BananaPi To: monnier@iro.umontreal.ca, linux-sunxi@googlegroups.com References: <1438532305-5884-1-git-send-email-public_timo.s@silentcreek.de> <20150818153631.GH2547@lukather> <20151005173957.B1BD16C8150E@dd34104.kasserver.com> <7hzizu924y.fsf@deeprootsystems.com> <20151007154918.D6F856C800D4@dd34104.kasserver.com> Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org From: Hans de Goede Message-ID: <56162A28.8000104@redhat.com> Date: Thu, 8 Oct 2015 09:32:40 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 10/07/2015 05:01 PM, Stefan Monnier wrote: >> @Maxime: How should we handle this? In its current form, the patch applies >> only to the BananaPi dts by overriding the inherited opp from the SoC dtsi. >> In an earlier discussion, it was said that this can be done, even though it >> might not be the most elegant approach. But then again, I think it >> shouldn't be necessary to change the opp in the sun7i-a20.dtsi for all A20 >> boards since this is - to my knowledge - the first and only report that an >> A20 board has stability issues at the lower voltages (although not too many >> boards use voltage scaling yet). > > IIUC this setting doesn't affect signals external to the A20, so it > seems like it should be board-agnostic. This setting configures the voltage at the pmic output pin, not at the SoC power-input pins. And how much of the voltage actually makes it from the pmic to the SoC definitely is board-specific. So we are going to need board-specific opp-s in some cases (like this one for example). Regards, Hans