On Fri, 20 Feb 2009, Alessandro Zummo wrote: > On Fri, 20 Feb 2009 16:46:44 +0100 > Geert Uytterhoeven <Geert.Uytterhoeven@xxxxxxxxxxx> wrote: > > Fortunately there already exists a generic RTC class driver: "rtc-parisc". > > Despite it's name, it's platform-independent, as it's build on top of the RTC > > abstraction used by "genrtc". > > > > This patch series > > - adds a missing module alias to rtc-parisc, > > - renames rtc-parisc to rtc-generic, > > - converts the architectures that currently have CONFIG_GEN_RTC enabled in > > their defconfig (m68k, parisc, powerpc) to rtc-generic, > > - removes the obsolete rtc-ppc driver, > > - removes the old genrtc driver. > > > > Note that genrtc may be used on other archictectures as well: at least alpha > > has the required infrastructure ([gs]et_rtc_time()). The Kconfig rules allow > > genrtc to be enabled on several others (cris, h8300, mn10300, um, x86, xtensa). > > > > Furthermore genrtc and rtc-generic are not 100% userspace compatible: > > - /dev/rtc provided by genrtc uses a misc character device (10:135), > > - /dev/rtc provided by rtc-generic uses a dynamic character device. > > Hello, > > my opinion on this kind of stuff is that I want to avoid the layering > of implementations under the rtc subsystem. I'd rather prefer that each > rtc device had its own driver. > > I've made error in the past, by accepting such kind of drivers, and > would like to avoid that it happens again. So you want us to kill the ppc_md.[gs]et_rtc_time() [ppc], mach_hwclk() [m68k], mach_gettod() [m68knommu] (and probably a few other) abstractions, and move all RTC code out of arch/ into seperate drivers under drivers/rtc/ instead? What about ppc_md.get_boot_time() [ppc]? Please note that the functions above may also be used for very early clock setting (e.g. time_init()) and in read_persistent_clock(). How should we handle these? Even on x86 there seems to be way too much RTC logic in arch/x86/kernel/rtc.c (e.g. mach_get_cmos_time()), which is duplicated in drivers/rtc/rtc-cmos.c through the inline function __get_rtc_time() in include/asm-generic/rtc.h (clever, hardware-specific stuff in asm-generic ;-) > Regarding the user space, the assumption that a device has > a fixed major:minor number should be dropped as well. I know. But it's a userland-visible change, so I wanted to explicit point to it. 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@xxxxxxxxxxx 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-parisc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
