Re: [PATCH 1/1] LinuxPPS: Pulse per Second support for Linux

From: Rodolfo Giometti
Date: Thu Feb 22 2007 - 03:51:05 EST

On Wed, Feb 21, 2007 at 08:14:14AM -0800, H. Peter Anvin wrote:
> If you have a kernel driver at all, then it makes perfect sense. If you
> don't have a kernel driver at all, then it's irrelevant to the
> linux-kernel discussion.


So you are told me that if my PPS source is connected with a single
CPU GPIO I have to add a new driver to the kernel? I have to choose a
proper major/minor numbers for just one PIN? =:-o

> >RFC simply doesn't consider the fact that you can have a PPS source
> >__without__ a filedes connected with, and a single filedes is
> >considered __always__ connected with a single PPS source.
> That's the Unix way.

But not PPS one. In several embedded systems the GPS antenna is
connected with the serial port and the PPS source, which cames from
the __same__ GPS antenna, is connected with a GPIO.

How I should manage such case? Which fildes I should use? Also
consider that NTPD currently manage only one filedes which should
support both GPS antenna's data and PPS source. My patch can solve
this problem.




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