[LinuxPPS] LinuxPPS - odd behaviour.

[Rodolfo Giometti]

On Sun, Nov 11, 2007 at 12:28:08PM +0100, Udo van den Heuvel wrote:
> Rodolfo Giometti wrote:
> > On Sun, Nov 11, 2007 at 11:38:01AM +0100, Udo van den Heuvel wrote:
> >> Rodolfo Giometti wrote:
> >>> On Sat, Nov 10, 2007 at 02:03:18PM +0100, Udo van den Heuvel wrote:
> >>>> See?
> >>>>
> >>>> http://bugs.ntp.org/956
> >>> I think they are right. Unluckely I have no idea about to open a
> >>> "parent" device when the PPS device is opened! :'(
> >> Just ask on linux-kernel on how to fix this issue?
> >> It's just an 'open' for kernel-land. The user gets no handle.
> > 
> > I can ask but it's not an easy task... I think the best way to do is
> > to mark this issue as a "know-bug"(TM) and suggest the cure by using
> > "cat" or so.
> 
> That could be the current workaround. `cat` or NMEA or whatever.
> You could add a request for help to solve this issue in a more elegant
> manner.

I see, however you should consider that this problem is due the fact
serial ports doesn't enable their IRQ lines untill they are open()ed,
that's why you cannot receive PPS events without doing 'cat' on
relative serial port.

Other devices whose enable by default their IRQ line (like parallel
port if I well remember) are not affected at all.

Ciao,

Rodolfo

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