Re: [rtc-linux] Re: [PATCH/RFC 0/5] Generic RTC class driver

Alessandro Zummo
2009-02-23T15:05:26Z

On Mon, 23 Feb 2009 13:34:49 +0100 (CET)
Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> wrote:

> > 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?

not all at once :)

I'd start writing a working driver and then see how we should eventually
adapt the rtc subsystem to cope with your needs.

> 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?

read_persistent_clock is something that should be reconsidered
as well along with all the ntp stuff.

> 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 ;-)

yep, I know :( that hardcoded rtc stuff seems to be everywhere!

--

Best regards,

Alessandro Zummo,
Tower Technologies - Torino, Italy