From mboxrd@z Thu Jan  1 00:00:00 1970
From: Richard Cochran <richardcochran@gmail.com>
Subject: Re: ptp
Date: Wed, 7 Sep 2016 23:12:23 +0200
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On Wed, Sep 07, 2016 at 01:55:19PM -0700, Daniel Walker wrote:
> So the code only allows second granularity negative updates,

No.

> or the seconds
> component is the only part which needs to actually be negative ?

Yes.

See the function, clockadj_step, in linuxptp/clockadj.c for a working
user space example.

Thanks,
Richard