Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751959AbdFKT53 (ORCPT ); Sun, 11 Jun 2017 15:57:29 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:55899 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751794AbdFKT52 (ORCPT ); Sun, 11 Jun 2017 15:57:28 -0400 Subject: Re: [PATCH v1 1/1] gpio: of: provide option generic property for initial line states To: Oleksij Rempel , Rob Herring References: <20170609141622.21502-1-o.rempel@pengutronix.de> <20170611061919.jsbc7x67ut4segj5@pengutronix.de> CC: Oleksij Rempel , "kernel@pengutronix.de" , Linus Walleij , Alexandre Courbot , Mark Rutland , "linux-gpio@vger.kernel.org" , "devicetree@vger.kernel.org" , "linux-kernel@vger.kernel.org" , From: Vladimir Zapolskiy Message-ID: <2432df7e-5d20-42c9-ddc0-044c2ca5ce2b@mentor.com> Date: Sun, 11 Jun 2017 22:57:18 +0300 User-Agent: Mozilla/5.0 (X11; Linux i686; rv:45.0) Gecko/20100101 Icedove/45.2.0 MIME-Version: 1.0 In-Reply-To: <20170611061919.jsbc7x67ut4segj5@pengutronix.de> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit X-Originating-IP: [137.202.0.87] X-ClientProxiedBy: svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) To SVR-IES-MBX-04.mgc.mentorg.com (139.181.222.4) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1742 Lines: 52 Hi Oleksij, On 06/11/2017 09:19 AM, Oleksij Rempel wrote: > Hi Rob, > > On Fri, Jun 09, 2017 at 10:41:30AM -0500, Rob Herring wrote: >> On Fri, Jun 9, 2017 at 9:16 AM, Oleksij Rempel wrote: >>> This property is needed for barebox or may be other bootloaders >>> to set proper gpio configuration as early as possible. >>> >>> This example is mainly based on "lines-initial-states" property >>> from this binding documentation: >>> Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt >> >> Don't we have a binding for this already based on gpio-hogs. > > Markus Pargmann was working on this topic before and suddenly was not > able to finish it. that's fine, but the proposed extension is supposedly not wanted. > I found only some not finished discussions and no code or documentation > in linux kernel upstream. > > So far, I was able to find fallowing patches and discussions: > patch 23.08.2015, last comment 11.05.2017: > https://patchwork.kernel.org/patch/7096721/ > > patch 23.02.2016, last comment 09.03.2016: > https://patchwork.ozlabs.org/patch/586743/ > > Since there was objections about node-like design for gpio-initval, I > provided an array property, which is similar to initval properties already used > for different other device nodes. For example: > > Documentation/devicetree/bindings/net/wireless/qcom,ath10k.txt > qcom,ath10k-calibration-data > > Documentation/devicetree/bindings/gpio/gpio-pcf857x.txt > lines-initial-states It'd rather be better to fix the drivers and remove the properties from these found device tree binding descriptions. > > Please fixme if I miss something. Why is GPIO hogging mechanism not good enough for your purpose? -- With best wishes, Vladimir