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=-6.9 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 D080EC43143 for ; Tue, 2 Oct 2018 11:10:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 834F0206B2 for ; Tue, 2 Oct 2018 11:10:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="MfUe7O/o" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 834F0206B2 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 S1727482AbeJBRxE (ORCPT ); Tue, 2 Oct 2018 13:53:04 -0400 Received: from perceval.ideasonboard.com ([213.167.242.64]:40918 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727244AbeJBRxE (ORCPT ); Tue, 2 Oct 2018 13:53:04 -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 1371FB7F; Tue, 2 Oct 2018 13:10:17 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1538478617; bh=qfENirQdex8moT0jHhtyaBqkZ60FYletjMkQYxhNQdY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MfUe7O/od0s4mqE2GkC1CDwN8/OzTROqf5vWNR5DZigGhbYbIyj/4XSujTKhiHDLj +gj/Mjzkanfhem2RYWxPq9g7xYR9timMZD4LechFLjfE5ZwuFUjXLgHDubjcVRS/GB 66sWZMi5lMz21XnEv6I4w5ke++kJGBRcrjpl22fU= From: Laurent Pinchart To: Ricardo Ribalda Delgado Cc: Pavel Machek , Sakari Ailus , Mauro Carvalho Chehab , linux-media , LKML , Hans Verkuil , devicetree@vger.kernel.org Subject: Re: [PATCH v5 2/6] [media] ad5820: DT new optional field enable-gpios Date: Tue, 02 Oct 2018 14:10:33 +0300 Message-ID: <13152589.2v2DAIKa7y@avalon> Organization: Ideas on Board Oy In-Reply-To: References: <20181002073222.11368-1-ricardo.ribalda@gmail.com> <2128166.ZAkUExjJHM@avalon> 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 Tuesday, 2 October 2018 13:57:22 EEST Ricardo Ribalda Delgado wrote: > On Tue, Oct 2, 2018 at 12:35 PM Laurent Pinchart wrote: > > On Tuesday, 2 October 2018 10:32:18 EEST Ricardo Ribalda Delgado wrote: > > > Document new enable-gpio field. It can be used to disable the part > > > without turning down its regulator. > > > > > > Cc: devicetree@vger.kernel.org > > > Signed-off-by: Ricardo Ribalda Delgado > > > Acked-by: Pavel Machek > > > --- > > > > > > Documentation/devicetree/bindings/media/i2c/ad5820.txt | 7 +++++++ > > > 1 file changed, 7 insertions(+) > > > > > > diff --git a/Documentation/devicetree/bindings/media/i2c/ad5820.txt > > > b/Documentation/devicetree/bindings/media/i2c/ad5820.txt index > > > 5940ca11c021..9ccd96d3d5f0 100644 > > > --- a/Documentation/devicetree/bindings/media/i2c/ad5820.txt > > > +++ b/Documentation/devicetree/bindings/media/i2c/ad5820.txt > > > > > > @@ -8,6 +8,12 @@ Required Properties: > > > - VANA-supply: supply of voltage for VANA pin > > > > > > +Optional properties: > > > + > > > + - enable-gpios : GPIO spec for the XSHUTDOWN pin. Note that the > > > polarity of +the enable GPIO is the opposite of the XSHUTDOWN pin > > > (asserting the enable +GPIO deasserts the XSHUTDOWN signal and vice > > > versa). > > > > After reading this one more time, I think the text is at the very least > > confusing. The logic level of the enable GPIO is the same as the logic > > level of the XSHUTDOWN pin. The latter being active low, asserting > > "enable" will deassert "shutdown", but talking about "desserting > > XSHUTDOWN" is confusing. > > what about: > > - enable-gpios : GPIO spec for the XSHUTDOWN pin. When the XSHUTDOWN pin > is asserted the device is enabled. For some reason "asserting a pin" doesn't seem right to me. How about - enable-gpios: GPIO spec for the XSHUTDOWN pin. The XSHUTDOWN signal is active low, a high level on the pin enables the device. > > > of +the enable GPIO is the opposite of the XSHUTDOWN pin (asserting the > > > enable +GPIO deasserts the XSHUTDOWN signal and vice versa). > > > > > > Example: > > > ad5820: coil@c { > > > > > > @@ -15,5 +21,6 @@ Example: > > > reg = <0x0c>; > > > > > > VANA-supply = <&vaux4>; > > > > > > + enable-gpios = <&msmgpio 26 GPIO_ACTIVE_HIGH>; > > > > > > }; > > > > -- > > Regards, > > > > Laurent Pinchart -- Regards, Laurent Pinchart