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 82AC8C76196 for ; Fri, 31 Mar 2023 09:40:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231223AbjCaJkK (ORCPT ); Fri, 31 Mar 2023 05:40:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57986 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231942AbjCaJkI (ORCPT ); Fri, 31 Mar 2023 05:40:08 -0400 Received: from mail11.truemail.it (mail11.truemail.it [217.194.8.81]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5CC274EEB; Fri, 31 Mar 2023 02:40:05 -0700 (PDT) Received: from francesco-nb.int.toradex.com (93-49-2-63.ip317.fastwebnet.it [93.49.2.63]) by mail11.truemail.it (Postfix) with ESMTPA id C99BA207CC; Fri, 31 Mar 2023 11:40:02 +0200 (CEST) Date: Fri, 31 Mar 2023 11:40:01 +0200 From: Francesco Dolcini To: Krzysztof Kozlowski Cc: Francesco Dolcini , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , dri-devel@lists.freedesktop.org, Rob Herring , Krzysztof Kozlowski , Peter Ujfalusi , devicetree@vger.kernel.org, Francesco Dolcini , David Airlie , Daniel Vetter , linux-kernel@vger.kernel.org Subject: Re: [PATCH v1 3/6] dt-bindings: display: bridge: toshiba,tc358768: add parallel input mode Message-ID: References: <20230330095941.428122-1-francesco@dolcini.it> <20230330095941.428122-4-francesco@dolcini.it> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 31, 2023 at 10:48:15AM +0200, Krzysztof Kozlowski wrote: > On 30/03/2023 11:59, Francesco Dolcini wrote: > > From: Francesco Dolcini > > > > Add new toshiba,input-rgb-mode property to describe the actual signal > > connection on the parallel RGB input interface. > > > > Signed-off-by: Francesco Dolcini > > --- > > .../bindings/display/bridge/toshiba,tc358768.yaml | 15 +++++++++++++++ > > 1 file changed, 15 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml b/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > index 8f22093b61ae..2638121a2223 100644 > > --- a/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > +++ b/Documentation/devicetree/bindings/display/bridge/toshiba,tc358768.yaml > > @@ -42,6 +42,21 @@ properties: > > clock-names: > > const: refclk > > > > + toshiba,input-rgb-mode: > > + description: | > > + Parallel Input (RGB) Mode. > > + > > + RGB inputs (PD[23:0]) color arrangement as documented in the datasheet > > + and in the table below. > > + > > + 0 = R[7:0], G[7:0], B[7:0] > > RGB888? Or anything else - like a RGB666 - just connecting to GND the unused pins. > > + 1 = R[1:0], G[1:0], B[1:0], R[7:2], G[7:2], B[7:2] > > + 2 = 8’b0, R[4:0], G[5:0], B[4:0] > > Isn't this RGB565? > > Don't we have already properties like this? e.g. colorspace? It's not really the colorspace this property. tc358768 is a parallel RGB to DSI bridge, it has 24 bit parallel input line. The way this lines are connected is configurable with this parameter, if you look at mode 0 and 1 they all allow to have a RGB888 or a RGB666 or a RGB565 mapping. This just configure some internal mux, it's not strictly about the RGB mode. The description for mode 2 was copied from the datasheet, and I agree this is really about having a RGB565 on the first 16 parallel input pins. Honestly I do not know what is going to happen with PD[23-16] if they are not connected to GND, given that the component does not know the parallel input bus width it might as well sample those pins in some un-documented way. Francesco