[LinuxPPS] Kernel 2.6.24.7

[Hal V. Engel]

On Friday 14 November 2008 14:38:48 Daniel Havey wrote:
> Sorry about the second thread.  I was in digest mode.
> Sorry about the second thread.
>
> Daniel Havey wrote:
> > I have kernel 2.6.24.7 and I applied this patch ntp-pps-2.6.24.diff
> > However, the PPS line discipline does not exist when I run menuconfig.
> > Also the ppsldisc.c program does not exist.
>
> Please use a more recent kernel.
> Then be sure the patchapplies cleanly.
>
> Udo
>
> Thanks Udo, but that may be problematic.  I'm sure that the 2.5.24.7 Kernel
> that we are using has been hacked to support some Click Modular router
> stuff that we are doing.  I was hoping for a 2.6.24.7 kernel solution.  The
> patch applied cleanly.  I just don't have the /dev/ppsx's and the
> instructions seem to deviate from what the patch actually did.

The reason Udo recommended using a newer kernel is that the LinuxPPS code has 
changed significantly in recent months and those changes are only available in 
the patch sets for newer kernels.  You need to use at least 2.6.26 if you want 
line discipline.  And you are right the existing documentation will not be 
correct if you are using an older kernel and patch set since the docs reflect 
the newer versions pf LinuxPPS.

The likely reason that you are missing /dev/pps* is that this device will not 
exist until you run something that creates the device.  This is one of those 
areas where the current patches are different than the older patch sets and 
off hand I don't remember what you need to do to get the device to appear with 
the version you are using.  Most everyone here is running 2.6.26 or 2.6.27 
kernels now.  There is a real possibility that the LinuxPPS patch set will 
become part of the kernel tree in 2.6.29 so this will get easier at some 
point. 

Hal