Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757355AbZCCKlx (ORCPT ); Tue, 3 Mar 2009 05:41:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756805AbZCCKll (ORCPT ); Tue, 3 Mar 2009 05:41:41 -0500 Received: from vervifontaine.sonytel.be ([80.88.33.193]:54335 "EHLO vervifontaine.sonycom.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754070AbZCCKlj (ORCPT ); Tue, 3 Mar 2009 05:41:39 -0500 Date: Tue, 3 Mar 2009 11:41:23 +0100 (CET) From: Geert Uytterhoeven To: Alessandro Zummo cc: Richard Zidlicky , rtc-linux@googlegroups.com, David Woodhouse , linux-parisc@vger.kernel.org, Linux Kernel Development , Kyle McMartin , Linux/PPC Development , Linux/m68k , Benjamin Herrenschmidt Subject: Re: [rtc-linux] Re: [PATCH/RFC 0/5] Generic RTC class driver In-Reply-To: <20090302120950.0d35e06c@i1501.lan.towertech.it> Message-ID: References: <1235144809-32468-1-git-send-email-Geert.Uytterhoeven@sonycom.com> <20090220170454.04382e9e@i1501.lan.towertech.it> <1235511327.18632.73.camel@macbook.infradead.org> <20090224231154.60ba18d6@i1501.lan.towertech.it> <1235514727.18632.93.camel@macbook.infradead.org> <20090225111836.621412c1@i1501.lan.towertech.it> <20090227185514.GA1071@linux-m68k.org> <20090302110310.35af50ea@i1501.lan.towertech.it> <20090302120950.0d35e06c@i1501.lan.towertech.it> User-Agent: Alpine 2.00 (LRH 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=ISO-8859-15 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3306 Lines: 82 On Mon, 2 Mar 2009, Alessandro Zummo wrote: > On Mon, 2 Mar 2009 11:28:01 +0100 (CET) > Geert Uytterhoeven wrote: > > So I can solve my problem (autoloading the RTC driver on PS3 by udev) by > > converting the old genrtc driver into a platform device driver and creating > > platform devices where appropriate. > > yes. btw, if you are building a kernel specific for the PS3, I would > compile the rtc driver statically, otherwise it won't be available > early on boot. > > > However, this doesn't solve the distro's problem: as the old RTC framework > > depends on RTC_LIB=n, you cannot have both old and new RTC drivers in your > > (single) distro kernel. That's why dmwm2 created drivers/rtc/rtc-ppc.c: Fedora > > had to support machines with both old and new RTC drivers. As all of the old > > drivers are actually behind the ppc_md.[sg]et_rtc_time() abstraction, this was > > very easy. > > ok, generic kernel. you will have to load the modules on initrd. no, sadly you > can't have both of them. you might stick with the old interface or > convert them all. > > > Hence it's all or nothing, and we have to convert all of them. > > > > drivers/rtc/rtc-generic.c would allow to have a working system without old > > RTC drivers, until all low-level code has been converted to individual RTC > > drivers. > > I know but I have enough experience to foresee that once a generic over generic > framework is in place it's very hard to get rid of it because people > will have no incentives. I know. > If you really need rtc-generic you can keep using it even if it's > not in the kernel, distributions often have their specific > set of kernel patches. rtc-generic is already in the kernel, it's just called rtc-parisc ;-) > But I'd strongly suggest to plan and execute a conversion process. So would you accept a patch series that: 1. Adds the missing module aliases to rtc-parisc (which is a bugfix), 2. Moves the platform device creation out of rtc-ppc and into arch-specific code (which is also a bugfix), 3. Consolidates rtc-parisc and rtc-ppc into rtc-generic (which is a cleanup), 4. Makes rtc-generic dependent on PARISC, PPC, and M68K (the existing [sg]et_rtc_time() users): a. without introducing ARCH_HAS_GENERIC_RTC, b. with a big fat warning in the Kconfig comment not relaxing the dependencies, as it's supposed to go away. 4. Converts the PS3 RTC support into a separate driver, called rtc-ps3 (as a bonus ;-) ? If yes, I'll cook it up. Other RTC platform support can be converted into separate drivers later. Thanks! With kind regards, Geert Uytterhoeven Software Architect Sony Techsoft Centre Europe The Corporate Village ? Da Vincilaan 7-D1 ? B-1935 Zaventem ? Belgium Phone: +32 (0)2 700 8453 Fax: +32 (0)2 700 8622 E-mail: Geert.Uytterhoeven@sonycom.com Internet: http://www.sony-europe.com/ A division of Sony Europe (Belgium) N.V. VAT BE 0413.825.160 ? RPR Brussels Fortis ? BIC GEBABEBB ? IBAN BE41293037680010 -- 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/