From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752071AbaHUP7Z (ORCPT ); Thu, 21 Aug 2014 11:59:25 -0400 Received: from mail-wi0-f174.google.com ([209.85.212.174]:47345 "EHLO mail-wi0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751776AbaHUP7X (ORCPT ); Thu, 21 Aug 2014 11:59:23 -0400 Message-ID: <53F61754.6010206@gmail.com> Date: Thu, 21 Aug 2014 17:59:16 +0200 From: Tomasz Figa User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.0 MIME-Version: 1.0 To: Pankaj Dubey , "'Bartlomiej Zolnierkiewicz'" , "'Arnd Bergmann'" , "'Lee Jones'" CC: linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, linux@arm.linux.org.uk, t.figa@samsung.com, vikas.sajjan@samsung.com, joshi@samsung.com, naushad@samsung.com, thomas.ab@samsung.com, chow.kim@samsung.com, "'Kukjin Kim'" , PRASHANTH GODREHAL Subject: Re: [PATCH v7 3/4] ARM: EXYNOS: Add platform driver support for Exynos PMU References: <1404878455-31518-1-git-send-email-pankaj.dubey@samsung.com> <53D238E1.3030901@gmail.com> <002601cfaa11$93de5060$bb9af120$@samsung.com> <2491338.uD82s4TcKJ@amdc1032> <53F35F94.1010101@gmail.com> <001601cfbd49$72359450$56a0bcf0$@samsung.com> In-Reply-To: <001601cfbd49$72359450$56a0bcf0$@samsung.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 21.08.2014 16:07, Pankaj Dubey wrote: > +Arnd, Lee Jones > > Hi Tomasz, > > On Tuesday, August 19, 2014 Tomasz Figa wrote: > >> >> Hi Bart, >> >> On 18.08.2014 19:42, Bartlomiej Zolnierkiewicz wrote: >>> >>> Hi, >>> >>> On Monday, July 28, 2014 08:40:52 AM Pankaj Dubey wrote: >>>> Hi Tomasz, >>>> >>>> On Friday, July 25, 2014 Tomasz Figa wrote: >>>> >>>>> To: Pankaj Dubey; 'Kukjin Kim'; >>>>> linux-arm-kernel@lists.infradead.org; >>>> linux- >>>>> samsung-soc@vger.kernel.org; linux-kernel@vger.kernel.org >>>>> Cc: linux@arm.linux.org.uk; t.figa@samsung.com; >>>>> vikas.sajjan@samsung.com; joshi@samsung.com; naushad@samsung.com; >>>>> thomas.ab@samsung.com; chow.kim@samsung.com >>>>> Subject: Re: [PATCH v7 3/4] ARM: EXYNOS: Add platform driver support >>>>> for Exynos PMU >>>>> >>>>> Hi Pankaj, Kukjin, >>>>> >>>>> On 25.07.2014 07:32, Pankaj Dubey wrote: >>>>>> Hi Kukjin, >>>>>> >>>>>> On Friday, July 25, 2014 Kukjin Kim wrote: >>>>> >>>>> [snip] >>>>> >>>>>>>> >>>>>>> Looks good to me, will apply this and 4/4. >>>>>>> >>>>>> >>>>>> We need to hold these two patches until dependent patch [1] from >>>>>> Tomasz Figa gets merged. >>>>>> >>>>>> [1]: mfd: syscon: Decouple syscon interface from syscon devices >>>>>> https://lkml.org/lkml/2014/6/24/188 >>>>> >>>>> That RFC patch had few comments from Arnd needed to be addressed, so >>>>> it >>>> needs a >>>>> new revision. >>>>> >>>>> Pankaj, If I remember correctly, we had talked about this and the >>>> conclusion was that >>>>> you would take care of addressing the comments and sending new >>>>> version of >>>> the >>>>> patch. Any update on this or have I missed something? >>>>> >>>> >>>> Well, I don't think we concluded as such anything. >>>> Since this patch needs to get in so that Exynos PMU and PM related >>>> changes can go in, I discussed with you saying that I am not able to >>>> understand about Arnd's comments and if possible and time permits I >>>> will look into it. Meanwhile I got busy with some other official >>>> work, so could not get time to look into it. >>> >>> Tomasz/Pankaj, could we please get some agreement on what needs to be >>> done and who should do the pending work? >>> >>> syscon patch is blocking PMU cleanup patches which in turn are >>> blocking PMU support additions for new SoCs (Exynos5420/5800 and >>> Exynos3250 PMU patches). >> >> Leaving alone the matter who is going to take care of it for now, the > remaining work >> to do is to further decouple syscon from struct device, which means > providing of_ >> API to register a syscon provider on a device tree node even before driver > model is >> available yet. >> > > As per Arnd's comment on your RFC patch he mentioned - > "I believe the part you are missing is that with the approach I suggested, > there would be no registration function at all." > > I think he is not in favor of adding such registration function at all. So > do you think > adding such function will really solve the problem? > > Further even Lee Jones agreed to Arnd's point of making syscon independent > of device, > but he also mentioned that it can be done in subsequent patch. Let's look again at the original thread then... I believe Lee agreed with my proposed solution or at least he quoted my e-mail and pointed that further work addressing Arnd's comments could be done in follow up patches. I also think that we should rather make one step as a time, especially this patch is required for further clean-up of Exynos. However there was also a reply from Michal Simek, which pointed out that even with my patch the syscon is still bound to driver model and for his use case he would need a purely OF-based version of the API. That's why I think my patch should be re-spun with changes I mentioned in my previous message in this thread. > > So in IMHO, your RFC patch can be taken as is, and any further improvement > suggested > by Arnd can be done in subsequent patches, because as I can see in 3.17-rc1 > still > has user of syscon_regmap_lookup_by_pdevname (clps711x.c) so we can't > completely > make it independent of platform_device as of now and also the changes > required > as per Arnd's suggestions requires considerable effort and time. Agreed. However we can still provide OF-only syscon registration function and modify look-up functions to allow syscons without struct device pointer, just with OF node. Best regards, Tomasz