From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751306AbeCIJEh (ORCPT ); Fri, 9 Mar 2018 04:04:37 -0500 Received: from relay3-d.mail.gandi.net ([217.70.183.195]:58544 "EHLO relay3-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751045AbeCIJEc (ORCPT ); Fri, 9 Mar 2018 04:04:32 -0500 Date: Fri, 9 Mar 2018 10:04:22 +0100 From: jacopo mondi To: Geert Uytterhoeven Cc: Jacopo Mondi , Archit Taneja , Andrzej Hajda , Laurent Pinchart , David Airlie , Simon Horman , Magnus Damm , Niklas =?utf-8?Q?S=C3=B6derlund?= , Sergei Shtylyov , Rob Herring , Mark Rutland , DRI Development , Linux-Renesas , "open list:OPEN FIRMWARE AND FLATTENED DEVICE TREE BINDINGS" , Linux Kernel Mailing List Subject: Re: [PATCH 1/3] dt-bindings: display: bridge: Document THC63LVD1024 LVDS decoder Message-ID: <20180309090422.GD14819@w540> References: <1520522643-11756-1-git-send-email-jacopo+renesas@jmondi.org> <1520522643-11756-2-git-send-email-jacopo+renesas@jmondi.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Geert, thanks for review On Fri, Mar 09, 2018 at 09:10:55AM +0100, Geert Uytterhoeven wrote: > Hi Jacopo, > > On Thu, Mar 8, 2018 at 4:24 PM, Jacopo Mondi wrote: > > Document Thine THC63LVD1024 LVDS decoder. > > > > Signed-off-by: Jacopo Mondi > > Thanks for your patch! > > > --- /dev/null > > +++ b/Documentation/devicetree/bindings/display/bridge/thine,thc63lvd1024.txt > > @@ -0,0 +1,59 @@ > > +THine Electronics THC63LVD1024 LVDS receiver > > Thine > > > +-------------------------------------------- > > + > > +The THC63LVD1024 is an LVDS receiver designed to convert multiple LVDS streams > > +to digital CMOS/TTL parallel data. > > + > > +Required properties: > > +- compatible: Shall be one of the following: > > + "thine,thc63lvd1024", > > + "lvds-decoder" > > What's the purpose of the second compatible value? > When should it be used? It is probably my bad having started with a generic LVDS decoder in mind and having then added properties specific to THC63LVD1024 to the driver and its bindings. "lvds,decoder" can be used when the chip is completely transparent to the SoC and none of the optional properties I have described in the bindings are specified (a generic "power-gpios" apart, see Andrzej comments on "pwdn-gpios" property). Also, I should make the driver behavior depend on the matched compatible string. When "lvds-decoder" is matched, it will just look for an optional power down gpio, when "thc63lvd1024" is matched, all of its Vcc supplies, pwdn gpio and oe gpios will be queried and, if present, eventually used in enable/disable routines. I'm just not sure how to describe that in bindings. Would something like the following work? Optional properties for "lvds,decoder" - power-gpios: Power control GPIOs Optional properties for "thine,thc63lvd1024" - pwdn-gpios: ... - oe-gpios: ... - supply-vcc: ... - supply-cvcc: ... - supply-pvcc: ... - supply-lvcc: ... Thanks j > > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds