Re: 2.6.25.3: serial problem (minicom)

Hans-Peter Jansen
2008-06-18T00:16:18Z

Am Dienstag, 17. Juni 2008 schrieb Alan Cox:
> On Mon, 16 Jun 2008 23:22:54 -0500 (CDT)
>
> "R.L. Horn" <lists@eastcheap.org> wrote:
> > On Mon, 16 Jun 2008, Alan Cox wrote:
> > > Whatever it implies the behaviour should not have changed between
> > > 2.6.24 and 2.6.25. Nobody AFAIK sat down and decided to change it.
> >
> > And, besides, I've gotten reports that the usb-serial drivers still
> > behave the same as with 2.6.24.
> >
> > It looks like the call to tty_termios_encode_baud_rate() in
> > drivers/serial/8250.c is the culprit. If I comment it out, everything
> > appears to go back to normal (seemingly with no undesired side
> > effects).
> >
> > Why the call is there (it didn't replace anything else in the 2.6.24.7
> > version of 8250.c, though it did in serial_core.c) remains a mystery to
> > me.
>
> Ah ok I know what the bug is - it was fixed in 2.6.26-rc as follows
>
> + /* Don't rewrite B0 */
> + if (tty_termios_baud_rate(termios))
> + tty_termios_encode_baud_rate(termios, baud, baud);
> }

Alan, could this issue lead to dysfunctional serial dcf77 receivers, too?
(and could you point my to the related git changeset?)

I'm using ntpd "127.127.8.0 mode 16" devices since a decade now (RAWDCF
receiver: DTR=low/RTS=high) and after upgrading to openSUSE 11.0, which is
using 2.6.25.5, those get no power anymore :-(.

Or do you have another idea? I currently prepare a test system, and would be
ready for kernel patching tomorrow..

TIA, Pete