Re: [PATCH] RTC: M41T80: Century Bit support

From: Atsushi Nemoto
Date: Sun May 18 2008 - 12:09:33 EST

On Sat, 17 May 2008 20:16:20 +0100 (BST), "Maciej W. Rozycki" <macro@xxxxxxxxxxxxxx> wrote:
> > How about doing like this?
> >
> > 1. If CEB was 0, keep current behavior. (does not touch CB bit)
> >
> > 2. If CEB was 1, detect polarity of CB bit on get_datetime, and set or
> > clear CB bit on set_datetime based on the polarity.
> That's what I did initially as it is as obvious as you can get. But as I
> noted, CFE, the firmware used with the SWARM, does not set CEB even though
> it takes CB into account. The approach is not useful therefore at least
> for one major user of the device.

Oh I had missed that the firmware does not set CEB. Hmm...

> Of course CFE is BSD-licensed and can be changed too, but based on my
> experience with how serious bugs are handled, I would not count on getting
> such a minor change integrated into the official sources.
> > Please look at "c_polarity" variable in rtc-pcf8563.c driver.
> Hmm, not terribly useful as few of us if anybody live back in the 20th
> century. ;-) I think let's scrap the patch in this case and let our
> grandchildren solve the problem -- a proposal has been published and can
> be reused as needed.

OK for me. Lets hear how our grandchildren complain on this fault. :)

Atsushi Nemoto
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at