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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D6255C433EF for ; Thu, 2 Jun 2022 13:38:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235469AbiFBNiJ (ORCPT ); Thu, 2 Jun 2022 09:38:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60636 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235467AbiFBNiE (ORCPT ); Thu, 2 Jun 2022 09:38:04 -0400 Received: from mail-oi1-f179.google.com (mail-oi1-f179.google.com [209.85.167.179]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B02212AB0F; Thu, 2 Jun 2022 06:38:03 -0700 (PDT) Received: by mail-oi1-f179.google.com with SMTP id i66so6514525oia.11; Thu, 02 Jun 2022 06:38:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Dr24Ejh5fpMmf0OXFd+psIEWSpHZUsdswYJ3//zAfIo=; b=3UGi1c7+leEQkUdI5U4R/kOBeRmtP5ONZlcxzRZeRg6sLeja6492GXyE8D2gI4NyXf sh+9XEkyOltEfCVBCcRziQoifnbVeoufqcpkxIhbyf9gYk8r2gF0dOnlbM2gRcwMevNR 2LJMbbSnHhry+B+ctjOuYnnacQdQNmdAKwQTOYuP3OARnjCRGe179uibYWp7fzmQjoK7 PT6fZPFsDSMljL2WA1in2Y1xw/CWYPS6BzCUE5dlIDkOoyBQfUU8MB4YMK+7lNRHvgF/ rXy6BRZlcpSDY+pFXkqFCl5yaM+JBiYV+DRQv+fWFZMRRSSRCJWzcRvaZIOdJ2lMXmP1 cGeQ== X-Gm-Message-State: AOAM531Sc/9dLpolpUg31eJyqMVU5Hh12qdg5zY4PD8XGXoNVf40HAUT 3G1zwY6tJuF6S8eJcbvwHg== X-Google-Smtp-Source: ABdhPJzJ1iMtezenD3KFf8yAadDOCOru3p9siXWTblKEYzkCHiU5Af93l/ltWLDlihAGNcNd23R/3A== X-Received: by 2002:a05:6808:1b2a:b0:32b:ce3d:7429 with SMTP id bx42-20020a0568081b2a00b0032bce3d7429mr2575849oib.221.1654177082778; Thu, 02 Jun 2022 06:38:02 -0700 (PDT) Received: from robh.at.kernel.org (66-90-144-107.dyn.grandenetworks.net. [66.90.144.107]) by smtp.gmail.com with ESMTPSA id mv26-20020a0568706a9a00b000f5701f240csm1906520oab.19.2022.06.02.06.38.02 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 02 Jun 2022 06:38:02 -0700 (PDT) Received: (nullmailer pid 2165669 invoked by uid 1000); Thu, 02 Jun 2022 13:38:01 -0000 Date: Thu, 2 Jun 2022 08:38:01 -0500 From: Rob Herring To: Douglas Anderson Cc: Jiri Kosina , linux-input@vger.kernel.org, Rob Herring , swboyd@chromium.org, devicetree@vger.kernel.org, Dmitry Torokhov , linux-kernel@vger.kernel.org, Benjamin Tissoires , Krzysztof Kozlowski , mka@chromium.org Subject: Re: [PATCH v2 1/2] dt-bindings: HID: i2c-hid: elan: Introduce bindings for Elan eKTH6915 Message-ID: <20220602133801.GA2165636-robh@kernel.org> References: <20220523142257.v2.1.Iedc61f9ef220a89af6a031200a7850a27a440134@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220523142257.v2.1.Iedc61f9ef220a89af6a031200a7850a27a440134@changeid> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org On Mon, 23 May 2022 14:23:23 -0700, Douglas Anderson wrote: > Like many i2c-hid touchscreen controllers, the Elan eKTH6915 > controller has a reset gpio. For the Goodix GT7375P touchscreen the > decision was to add a new binding rather than trying to add a new GPIO > to the existing i2c-hid binding. We'll follow the lead and do it here, > too. > > SIDE NOTE: the Elan eKTH6915 is a touchscreen _controller_ that's > included as a part on some touchscreens. The reset line isn't truly > necessary for the functioning of the touchscreen, so it's possible > that some designs won't have it hooked up and will just guarantee the > power sequencing requirements with RLC circuits. Thus, we'll mark the > reset gpio as optional. > > Note that if the reset GPIO isn't used there's actually no true need > to use the "elan,ekth6915" compatible instead of the "hid-over-i2c" on > Linux. However: > - Officially using just "hid-over-i2c" for this device violates the > existing "hid-over-i2c" bindings. The bindings say that you're not > supposed to use "post-power-on-delay-ms" without specifying a more > specific compatible. Currently the Linux driver doesn't enforce > this, but it violates the bindings to just use > "hid-over-i2c". ...and if you're going to add a more specific > compatible anyway, might as well do it right. > - Using this compatible means we don't need to specify > "hid-descr-addr" since it's inferred from the compatible. > - Using this compatible means that the regulator names match the names > on the Elan datasheet (vcc33 / vccio) vs the generic hid-over-i2c > (vdd / vddl). > > Signed-off-by: Douglas Anderson > --- > > (no changes since v1) > > .../bindings/input/elan,ekth6915.yaml | 65 +++++++++++++++++++ > 1 file changed, 65 insertions(+) > create mode 100644 Documentation/devicetree/bindings/input/elan,ekth6915.yaml > Reviewed-by: Rob Herring