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 5A614C77B70 for ; Fri, 14 Apr 2023 08:43:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230203AbjDNInH (ORCPT ); Fri, 14 Apr 2023 04:43:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52282 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229969AbjDNInD (ORCPT ); Fri, 14 Apr 2023 04:43:03 -0400 Received: from mail11.truemail.it (mail11.truemail.it [IPv6:2001:4b7e:0:8::81]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B008E7EC5; Fri, 14 Apr 2023 01:42:51 -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 81CE020B6B; Fri, 14 Apr 2023 10:42:45 +0200 (CEST) Date: Fri, 14 Apr 2023 10:42:42 +0200 From: Francesco Dolcini To: Rob Herring , Krzysztof Kozlowski Cc: Francesco Dolcini , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , dri-devel@lists.freedesktop.org, Krzysztof Kozlowski , 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> <20230403210117.GA1722054-robh@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230403210117.GA1722054-robh@kernel.org> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hello Rob and Krzysztof On Mon, Apr 03, 2023 at 04:01:17PM -0500, Rob Herring wrote: > On Fri, Mar 31, 2023 at 11:40:01AM +0200, Francesco Dolcini wrote: > > 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] > > 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. > > This is the same as other cases. There's a need for describing the > interface. It keeps coming up and I keep saying to go create something > common. Rob, Krzysztof: you both had concerns on this change and I am not sure how to progress. Let me summarize my current understanding. 1. I do not think that this change is related to the media bus format topic, this is more like the internal bridge RGB pins mux configuration. This `input-rgb-mode` field I am proposing here is orthogonal to the bus format (e.g. linux media-bus-format.h). I can change the name, if we think this is the reason of the confusion, I just used something similar to the words used in the datasheet. Do we have agreement on that or not? 2. Rob asked for a generic solution, since according to him this is a recurring need. I would appreciate some pointer where to look at so I can propose something more generic. Thanks, Francesco 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6ECE2C77B73 for ; Fri, 14 Apr 2023 08:42:55 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A1EB410EC88; Fri, 14 Apr 2023 08:42:54 +0000 (UTC) Received: from mail11.truemail.it (mail11.truemail.it [IPv6:2001:4b7e:0:8::81]) by gabe.freedesktop.org (Postfix) with ESMTPS id A7C5110EC93 for ; Fri, 14 Apr 2023 08:42:51 +0000 (UTC) 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 81CE020B6B; Fri, 14 Apr 2023 10:42:45 +0200 (CEST) Date: Fri, 14 Apr 2023 10:42:42 +0200 From: Francesco Dolcini To: Rob Herring , Krzysztof Kozlowski 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> <20230403210117.GA1722054-robh@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230403210117.GA1722054-robh@kernel.org> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Neil Armstrong , Robert Foss , Francesco Dolcini , Krzysztof Kozlowski , Jonas Karlman , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Jernej Skrabec , devicetree@vger.kernel.org, Laurent Pinchart , Andrzej Hajda , Francesco Dolcini Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hello Rob and Krzysztof On Mon, Apr 03, 2023 at 04:01:17PM -0500, Rob Herring wrote: > On Fri, Mar 31, 2023 at 11:40:01AM +0200, Francesco Dolcini wrote: > > 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] > > 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. > > This is the same as other cases. There's a need for describing the > interface. It keeps coming up and I keep saying to go create something > common. Rob, Krzysztof: you both had concerns on this change and I am not sure how to progress. Let me summarize my current understanding. 1. I do not think that this change is related to the media bus format topic, this is more like the internal bridge RGB pins mux configuration. This `input-rgb-mode` field I am proposing here is orthogonal to the bus format (e.g. linux media-bus-format.h). I can change the name, if we think this is the reason of the confusion, I just used something similar to the words used in the datasheet. Do we have agreement on that or not? 2. Rob asked for a generic solution, since according to him this is a recurring need. I would appreciate some pointer where to look at so I can propose something more generic. Thanks, Francesco