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 65676C433F5 for ; Sun, 22 May 2022 21:32:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351532AbiEVVcb (ORCPT ); Sun, 22 May 2022 17:32:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51358 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229853AbiEVVc2 (ORCPT ); Sun, 22 May 2022 17:32:28 -0400 Received: from mail-pg1-x536.google.com (mail-pg1-x536.google.com [IPv6:2607:f8b0:4864:20::536]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A2D6931221; Sun, 22 May 2022 14:32:27 -0700 (PDT) Received: by mail-pg1-x536.google.com with SMTP id a9so10089542pgv.12; Sun, 22 May 2022 14:32:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=3OR/Kmh2JnSnKKS3+ncrHc5sLSNg/DCoWnWM76fU65c=; b=gX0REAKHdflNjIemZSFgXuDUYDvJ5PoMB8gYReB87VKnfZM8YBNMm2N1euXJSzsty4 d2QLicPOwOis+GVrMfSbtoD50k9cYT6AHqskidY0EpFOe7+Z5ju2Sed86fgON2RkEOqr tH9JUjRpm9LFBRLsHpBnP2TVFRAhORZdX4uU0pfpimzhmBnn99/za0OSb9tmYDLA90pw ExAw4dkuAghhARC1kJHelFel5XTT1+TRONyjWuXMTcefGgITOstkeY90edNz5nEYmdnc oq4lhzcrVcjKnd49b4AENVPiSBxfzyEwqkwObjR9ygfzq+F0cNovFCTTCQqD7G03lVRx +gbA== 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=3OR/Kmh2JnSnKKS3+ncrHc5sLSNg/DCoWnWM76fU65c=; b=QCUCIjLFslnRA+biOIrvYRBTAJekuz7I2XqkiEfGUyrIdwI1dFjVwZHYxMwI3AtOwG 25UhKd5lPPpzxG1HHektFhD8yg8ZIo+joUYFxKDs9Q7oWBytQ6mXikDxMfXmhgiyzNm6 AQ0UAlGJu3oHCENlQfm/YfQytsmXlHV/B60pjAuIm4CETQAHNldpZ6t07uWEDLHKOYAS FIWU+xuEPTJcanrrMmfa0685uoW4TJrgGlR31qTWcefXs3JZg0jbs44y317zazVpK2vZ VmnPodxVT8mRTJ+Ubun6pc6aySF0ZH4qFoUdF+CveV26igk516Zk5m58nMq62XCGNtMu dbSg== X-Gm-Message-State: AOAM532Gj+r5s7rlIfKVo3Nk3/djT0XqVy4rqWiMH47NVcC8jXLDU1dY LLmytv4IY4PVy3D7IexITN0= X-Google-Smtp-Source: ABdhPJxP3JPqH02AHqbiN1izT+2dYEHPbp8DqBRkko/evSO60sWw2FlxPFTMtSPIq3kBbLGoJ+GAxQ== X-Received: by 2002:a05:6a00:e0e:b0:50a:cb86:883c with SMTP id bq14-20020a056a000e0e00b0050acb86883cmr20796278pfb.11.1653255147053; Sun, 22 May 2022 14:32:27 -0700 (PDT) Received: from google.com ([2620:15c:202:201:d84e:5dcd:9d68:ebbf]) by smtp.gmail.com with ESMTPSA id n18-20020a170902e55200b001616b8bad48sm3534926plf.303.2022.05.22.14.32.25 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 22 May 2022 14:32:26 -0700 (PDT) Date: Sun, 22 May 2022 14:32:23 -0700 From: Dmitry Torokhov To: Douglas Anderson Cc: Jiri Kosina , Benjamin Tissoires , Rob Herring , Krzysztof Kozlowski , swboyd@chromium.org, linux-input@vger.kernel.org, mka@chromium.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/2] dt-bindings: HID: i2c-hid: elan: Introduce bindings for Elan eKTH6915 Message-ID: References: <20220519155925.1.Iedc61f9ef220a89af6a031200a7850a27a440134@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220519155925.1.Iedc61f9ef220a89af6a031200a7850a27a440134@changeid> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 19, 2022 at 04:00:02PM -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 Reviewed-by: Dmitry Torokhov Thanks. -- Dmitry