Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751502Ab3G0LAx (ORCPT ); Sat, 27 Jul 2013 07:00:53 -0400 Received: from mms1.broadcom.com ([216.31.210.17]:1729 "EHLO mms1.broadcom.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751276Ab3G0LAu (ORCPT ); Sat, 27 Jul 2013 07:00:50 -0400 X-Server-Uuid: 06151B78-6688-425E-9DE2-57CB27892261 Message-ID: <51F3A82E.2000907@broadcom.com> Date: Sat, 27 Jul 2013 12:59:58 +0200 From: "Arend van Spriel" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130623 Thunderbird/17.0.7 MIME-Version: 1.0 To: "Tomasz Figa" cc: "Richard Cochran" , "Olof Johansson" , "Mark Brown" , "Mark Rutland" , "devicetree@vger.kernel.org" , "ksummit-2013-discuss@lists.linuxfoundation.org" , "Russell King - ARM Linux" , "Ian Campbell" , "Pawel Moll" , "Stephen Warren" , "Domenico Andreoli" , "rob.herring@calxeda.com" , "linux-kernel@vger.kernel.org" , "Jason Gunthorpe" , "Dave P Martin" , "linux-arm-kernel@lists.infradead.org" Subject: Re: [Ksummit-2013-discuss] DT bindings as ABI [was: Do we have people interested in device tree janitoring / cleanup?] References: <20130725175702.GC22291@e106331-lin.cambridge.arm.com> <2007664.vYsECFSKrV@flatron> <51F39FD8.6080808@broadcom.com> <2460092.aLmjrOVh1g@flatron> In-Reply-To: <2460092.aLmjrOVh1g@flatron> X-WSS-ID: 7DED78E231W56453604-01-01 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3895 Lines: 88 On 07/27/2013 12:36 PM, Tomasz Figa wrote: > On Saturday 27 of July 2013 12:24:24 Arend van Spriel wrote: >> On 07/27/2013 11:51 AM, Tomasz Figa wrote: >>> On Saturday 27 of July 2013 07:04:08 Richard Cochran wrote: >>>> On Fri, Jul 26, 2013 at 08:49:43AM -0700, Olof Johansson wrote: >>>>> Long term, final goal is likely to be close to what Russell is >>>>> saying >>>> >>>> Why is this a long term goal? Start today. >>>> >>>>> -- nothing should go into the kernel tree unless the binding is in a >>>>> fully stable state. However, we have a transitional period between >>>>> now >>>>> and then, and even when we're at the final state there will be need >>>>> to >>>>> have some sort of sandbox for development and test of future >>>>> bindings. >>>> >>>> Why not just set up a git tree right away? >>>> >>>>> Dealing with all that, as well as the actual process for locking in >>>>> bindings, is what needs to be sorted out. >>>>> >>>>> I think we're all in agreement that bindings that change over time >>>>> are >>>>> nothing but pain, but we're arguing that in circles anyway. >>>> >>>> No. >>>> >>>> I keep saying, the bindings must be stable ABI, *today*. >>>> >>>> You keep saying, maybe later, but until then we will make things up >>>> as >>>> we go along. >>> >>> We have currently a lot of broken bindings, because people didn't know >>> how to define ones and those they defined have not been properly >>> reviewed. Do you really want such broken ABI in the kernel? >>> >>> Sure, there are many existing bindings that can be just made stable >>> and >>> well they probably are already de facto stable. This is mostly about >>> subsystem bindings and whatever already has many users, both made them >>> get more thought when designing and more review before merging. >>> >>> Still, a lot of device and platform-specific bindings are simply >>> broken. Take max8925 backlight driver, that Olof started this whole >>> discussion with, as an example. We need to sort them out before they >>> can be stabilized. >> >> That is a nice summary of how we got from null to now and Richard seems >> to be simply saying: let's stop mucking about and make this a project >> with a well-defined process of dealing with staging and stable bindings >> and keep stable bindings stable. Whether it should be within the kernel >> repo as a separate subsystem or in an entire different repo is a trivial >> decision, but still a decision that needs to be made. > > Yes, basically that's our current situation. > > Still, I would disagree about the decision being trivial, as each choice > will have further, and likely pretty significant, consequences on binding > maintenance, submission, review and for dependent things, like drivers or > platforms using such bindings. This needs to be discussed enough. > >> Apart from stable DT bindings I would love to see a DT compiler that >> that next to DT syntax detects mistakes in properties used for the >> selfish reason that I spent hours debugging regulator code, because I >> typed vmmc_supply iso vmmc-supply. I did not go through all the >> bindings, but this may require a more formal description so it could be >> compiled/read in the DT compiler. > > This bothered me as well and that's why I'm working on this. I still can't > get myself to write a very long mail (I'm more a coder than writer...) > about the whole idea, my proposal of how it could look and problems we > need to solve, but I'll try better this evening. Let's see how many people go and scream if I say this: Too bad .dts files are not done using XML format as DT bindings could be described using XML Schema. Regards, Arend -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/