From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4AE27C433F4 for ; Thu, 20 Sep 2018 20:04:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CF42B2147D for ; Thu, 20 Sep 2018 20:04:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="VOabTww7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CF42B2147D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388550AbeIUBtT (ORCPT ); Thu, 20 Sep 2018 21:49:19 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:36120 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388212AbeIUBtT (ORCPT ); Thu, 20 Sep 2018 21:49:19 -0400 Received: from avalon.localnet (dfj612ybrt5fhg77mgycy-3.rev.dnainternet.fi [IPv6:2001:14ba:21f5:5b00:2e86:4862:ef6a:2804]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 782041C86; Thu, 20 Sep 2018 22:04:08 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1537473848; bh=N+Li+HCZuuNN6pBOpT0h2asOWFC/iQbWql3qEFClcgY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VOabTww7qBxqgR0TE8cRfZBaNAuldRg5kRHcplL0ybXLTuB5HB8xB7FwgLF7Qo4Be hh10lAFEAmuzSUB2ypb7ki6aIhtsuK9HhMoAiiGBqhay98LEhhbp/MGGKk/60OtbVR bcd5YY7XgQl983YiZ9EfQW8WaZD1cAisoTCgpc3Q= From: Laurent Pinchart To: Ricardo Ribalda Delgado Cc: Pavel Machek , Sakari Ailus , Mauro Carvalho Chehab , linux-media , LKML , Hans Verkuil Subject: Re: [PATCH v2 2/4] [media] ad5820: Add support for enable pin Date: Thu, 20 Sep 2018 23:04:21 +0300 Message-ID: <1887575.If169ivQRG@avalon> Organization: Ideas on Board Oy In-Reply-To: References: <20180920161912.17063-2-ricardo.ribalda@gmail.com> <20180920190855.GC26589@amd> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ricardo, On Thursday, 20 September 2018 22:12:44 EEST Ricardo Ribalda Delgado wrote: > On Thu, Sep 20, 2018 at 9:08 PM Pavel Machek wrote: > > On Thu 2018-09-20 21:06:16, Ricardo Ribalda Delgado wrote: > >> On Thu, Sep 20, 2018 at 8:54 PM Pavel Machek wrote: > >>> On Thu 2018-09-20 20:45:52, Ricardo Ribalda Delgado wrote: > >>>> This patch adds support for a programmable enable pin. It can be > >>>> used in situations where the ANA-vcc is not configurable (dummy- > >>>> regulator), or just to have a more fine control of the power saving. > >>>> > >>>> The use of the enable pin is optional. > >>>> > >>>> Signed-off-by: Ricardo Ribalda Delgado > >>> > >>> Do we really want to do that? > >>> > >>> Would it make more sense to add gpio-regulator and connect ad5820 to > >>> it in such case? > >> > >> My board (based on db820c) has both: > >> > >> ad5820: dac@0c { > >> compatible = "adi,ad5820"; > >> reg = <0x0c>; > >> > >> VANA-supply = <&pm8994_l23>; > >> enable-gpios = <&msmgpio 26 GPIO_ACTIVE_HIGH>; > >> }; > > > > Well, I'm sure you could have gpio-based regulator powered from > > pm8994_l23, and outputting to ad5820. > > > > Does ad5820 chip have a gpio input for enable? > > xshutdown pin: > http://www.analog.com/media/en/technical-documentation/data-sheets/AD5821.pd > f > > (AD5820,AD5821, and AD5823 are compatibles, or at least that is waht > the module manufacturer says :) Is that the pin that msmgpio 26 is connected to on your board ? I'd argue that the GPIO should be called xshutdown in that case, as DT usually uses the pin name, but there's precedent of using well-known names for pins with the same functionality. In any case you should update the DT bindings to document the new property, and clearly explain that it describes the GPIO connected to the xshutdown pin. Please CC the devicetree@vger.kernel.org mailing list on the bindings change (they usually like bindings changes to be split to a separate patch). -- Regards, Laurent Pinchart