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SubjectRe: Two issues with 2.4.18pre3 on PPC
>- The generic RTC driver in drivers/char/rtc.c does not work for this
> iBook. The driver in drivers/macintosh/rtc.c does work, but it only
> implements the two ioctls RTC_RD_TIME and RTC_SET_TIME. (Is this due to
> hardware limitations?) Anyway, it is confusing to have both drivers
> configurable for PPC, maybe the corresponding files should be
> adjusted. (In addition, this is complicated by the fact that both
> configuration options appear in different submenus and if you select
> both as modules, then the generic driver will "shadow" the macintosh
> one.)

That's a weirdness we haven't solved yet. Part of the problem is
that a common kernel can boot pmac, chrp and prep, and the later
ones can use the drivers/char/rtc.c driver. Actually, the
drivers/macintosh/rtc.c one may work on these too as it's just
a wrapper on some platform code selected at runtime depending on
the machine class.

Now, regarding the support of only GET/SET ioctls, it's normal.
Some of these machines don't have the legacy PC hardware RTC with
alarm support etc... That's the case of macs where the RTC hardware
is purely a real time clock. (It has other features, like scheduled
power up, but these aren't implemented yet and could be done entirely
in userland using /dev/adb anyway).

So the driver in drivers/macintosh/rtc.c is just a wrapper on the
get/set time functions provided by each type of machine.


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