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 25098C7EE25 for ; Wed, 7 Jun 2023 22:59:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232499AbjFGW7C (ORCPT ); Wed, 7 Jun 2023 18:59:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57132 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231720AbjFGW67 (ORCPT ); Wed, 7 Jun 2023 18:58:59 -0400 Received: from mail-io1-f50.google.com (mail-io1-f50.google.com [209.85.166.50]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 330B31FE3; Wed, 7 Jun 2023 15:58:58 -0700 (PDT) Received: by mail-io1-f50.google.com with SMTP id ca18e2360f4ac-77499bf8e8bso337322139f.0; Wed, 07 Jun 2023 15:58:58 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1686178737; x=1688770737; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=iB9XrQ+a6WIZmp+zbM7Qeq67vgXTSlPM9tziF9ThlVU=; b=AzcAxLFNK9c24EE3wIwa/nUQNnX3AuUTXnlWxPTsjypJgoo4GjOiFORDCWp1vRIYr/ QH/crDOq3SQ0kfPLnLJG11cM00StF/SmrgIOTuGLR1pd1eLETpnTQNvYIZKCoHaKAfTe 4nXoI5MtnQ0cVaT+YEwW5Q1NTNjErLKqIAJ7xXmjXjiWpmT0aiFVRnN2QUZNUyfnRaDX SEUHuoh53ymQCdR8oIXzQ6kjWDEVB0XIcRmA8jn2C1moPqZD3m/ZAjX9c0/oX3mVWuJf Lx3KZgtipTNTJ0hJe9GONSn1hJHw6M4DWLu6VOWRxv3w8J55brUqo8F+dL2QLv759M/v 03Sg== X-Gm-Message-State: AC+VfDyqn+0/MgHe494Khr3uD0pSBFdwLyAkbJzBjKeMePPhYdhq1xZ+ FMABQqbdOpsCIPvrsQdYtUGBiGD1VA== X-Google-Smtp-Source: ACHHUZ7GyWclAIE0PzlN9Vgtpl3sBod7vdf2FQhPd2yqzwfylkGB++YMGy6fetz+l45NA7qKGSVwng== X-Received: by 2002:a6b:e609:0:b0:76c:826f:2188 with SMTP id g9-20020a6be609000000b0076c826f2188mr6026686ioh.6.1686178737285; Wed, 07 Jun 2023 15:58:57 -0700 (PDT) Received: from robh_at_kernel.org ([64.188.179.250]) by smtp.gmail.com with ESMTPSA id i24-20020a02c618000000b00411baa5ec5asm3665517jan.154.2023.06.07.15.58.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 07 Jun 2023 15:58:56 -0700 (PDT) Received: (nullmailer pid 139626 invoked by uid 1000); Wed, 07 Jun 2023 22:58:48 -0000 Date: Wed, 7 Jun 2023 16:58:48 -0600 From: Rob Herring To: Noralf =?iso-8859-1?Q?Tr=F8nnes?= Cc: Leonard =?iso-8859-1?Q?G=F6hrs?= , Neil Armstrong , Sam Ravnborg , David Airlie , Daniel Vetter , kernel@pengutronix.de, Krzysztof Kozlowski , Conor Dooley , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 2/8] dt-bindings: display: panel: mipi-dbi-spi: add spi-3wire property Message-ID: <20230607225848.GA131389-robh@kernel.org> References: <20230607115508.2964574-1-l.goehrs@pengutronix.de> <20230607115508.2964574-2-l.goehrs@pengutronix.de> <69fdb6a2-12b6-547d-019b-c77dd2bd98cf@tronnes.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <69fdb6a2-12b6-547d-019b-c77dd2bd98cf@tronnes.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jun 07, 2023 at 09:59:47PM +0200, Noralf Trønnes wrote: > > > On 6/7/23 13:55, Leonard Göhrs wrote: > > Some MIPI DBI panels support a three wire mode (clock, chip select, > > bidirectional data) that can be used to ask the panel if it is already set > > up by e.g. the bootloader and can thus skip the initialization. > > This enables a flicker-free boot. > > > > Signed-off-by: Leonard Göhrs > > --- > > .../devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > > index c07da1a9e6288..2f0238b770eba 100644 > > --- a/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > > +++ b/Documentation/devicetree/bindings/display/panel/panel-mipi-dbi-spi.yaml > > @@ -87,6 +87,8 @@ properties: > > Logic level supply for interface signals (Vddi). > > No need to set if this is the same as power-supply. > > > > + spi-3wire: true > > + > > I don't think this should be added here. spi-cpha and spi-cpol are also > supported but they are not mentioned. Instead those are documented in > bindings/spi/spi-controller.yaml. Why they're not documented in > bindings/spi/spi-peripheral-props.yaml instead which this binding has a > ref to, I have no idea. spi-peripheral-props.yaml are properties of the controller in the peripheral nodes. spi-cpha and spi-cpol are properties of the device which are completely invalid on some devices. We can only check that by documenting where they are valid. I think spi-3wire is similar. There should be more explanation in the spi-peripheral-props.yaml commit history. Rob