CVS commit: src

["Greg Troxel" <gdt%netbsd.org@localhost>]

Module Name:    src
Committed By:   gdt
Date:           Fri Jul 25 16:13:21 UTC 2014

Modified Files:
        src/share/man/man4: ucom.4
        src/sys/dev/usb: ucom.c

Log Message:
Add PPS support to ucom(4).

This is basically cribbed from regular serial ports, and just adds
hooks to call the pps support routines.

Also, note in the ucom(4) man page that there is about 1 ms of
latency.  Discussed on tech-kern in October of 2013, with the only
concern being that someone who didn't know what they were doing might
set up a stratum 1 server, and that somehow might have worse
timekeeping than whatever else that person might have done; the man
page comment is a mitigation for this.

This patch has been live-tested in netbsd-5/i386 and netbsd-6/i386,
and has been running on machines without a USB-serial GPS device for
most of a year with no adverse consequences (very little happens if
the PPS ioctls are not invoked).


To generate a diff of this commit:
cvs rdiff -u -r1.23 -r1.24 src/share/man/man4/ucom.4
cvs rdiff -u -r1.105 -r1.106 src/sys/dev/usb/ucom.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.