From mboxrd@z Thu Jan 1 00:00:00 1970 From: Florian Vaussard Subject: Re: [PATCH 2/2] ARM: dts: duovero-parlor: Add HDMI output Date: Tue, 25 Feb 2014 14:05:26 +0100 Message-ID: <530C9516.7070501@epfl.ch> References: <1393261669-32039-1-git-send-email-florian.vaussard@epfl.ch> <1393261669-32039-3-git-send-email-florian.vaussard@epfl.ch> <20140224180336.GU27282@n2100.arm.linux.org.uk> <20140225123921.GY27282@n2100.arm.linux.org.uk> Reply-To: florian.vaussard@epfl.ch Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140225123921.GY27282@n2100.arm.linux.org.uk> Sender: linux-omap-owner@vger.kernel.org To: Russell King - ARM Linux , Javier Martinez Canillas Cc: Tomi Valkeinen , =?ISO-8859-1?Q?Beno=EEt_Cou?= =?ISO-8859-1?Q?sson?= , Tony Lindgren , "devicetree@vger.kernel.org" , "linux-omap@vger.kernel.org" , Ash Charles , "linux-arm-kernel@lists.infradead.org" List-Id: devicetree@vger.kernel.org Hi, On 02/25/2014 01:39 PM, Russell King - ARM Linux wrote: > On Mon, Feb 24, 2014 at 05:22:27PM -0300, Javier Martinez Canillas wrote: >> Hi Russell, >> >> On Mon, Feb 24, 2014 at 3:03 PM, Russell King - ARM Linux >> wrote: >>> On Mon, Feb 24, 2014 at 06:07:49PM +0100, Florian Vaussard wrote: >>>> + hdmi0: connector@0 { >>>> + compatible = "hdmi-connector"; >>> >>> This looks way to generic a compatible string. Are you sure it's >>> correct? >>> >> >> That compatible string is correct according to the latest series >> posted by Tomi Valkeinen to add DT bindings for the OMAP Display >> SubSystem (DSS) [0]. > > in which case: > > N N AA CCCC K K > NN N A A C C K K > N N N A A C KK > N N N AAAAAA C KK > N NN A A C C K K > N N A A CCCC K K > What a nice nack. > Yes, that's a very big nack. Two things: > > 1. OMAP really doesn't have the right to define a compatible string which > is as generic as "hdmi-connector". > > 2. Even with "omapdss," before it, the convention that DT people have adopted > is for the prefix to be "companyname," and not a subsystem. > > I'm not the only one with this concern - I discussed it with Arnd last > night and his comments were about it being "obviously bogus". > I agree. It should probably be "ti,omapdss-hdmi-connector", or simply "ti,hdmi-connector", if any. >> The property is added on this patch [1] and as far as I understood the >> idea is that it could be a generic DT binding that can be used by >> platform specific HDMI connectors like the omap dss HDMI connector [2]. > > Why do the physical connectors need a DT binding? Surely what needs the > DT binding is the HDMI encoder - and that certainly should no way be a > generic name, because there's no such thing as a generic HDMI encoder > chip. > The HDMI IP is declared in omap4.dtsi, with the compatible "ti,omap4-hdmi". The code of the HDMI connector [1] seems to mainly call ops of the connected endpoint, so it seems to act as a logical termination in the DSS chain, but I may be wrong. Regards, Florian [1] https://git.kernel.org/cgit/linux/kernel/git/tomba/linux.git/tree/drivers/video/omap2/displays-new/connector-hdmi.c?h=work%2Fdss-dt-review-3