clarify implementation of ethtool's get_ts_info op
authorJacob Keller <jacob.e.keller@intel.com>
Wed, 22 Apr 2015 21:40:30 +0000 (14:40 -0700)
committerJeff Kirsher <jeffrey.t.kirsher@intel.com>
Sat, 18 Jul 2015 02:59:04 +0000 (19:59 -0700)
commiteff3cddc222c88943ff515ae9335687c9e2cbaf6
tree75e6facb436fef4dc0c60526894cd65c83532462
parent0d0578815bac634aef6e64794e7ad2473fc7af44
clarify implementation of ethtool's get_ts_info op

This patch adds some clarification about the intended way to implement
both SIOCSHWTSTAMP and ethtool's get_ts_info. The HWTSTAMP API has
several Rx filters which are very specific, as well as more general
filters. The specific filters really only exist to support some broken
hardware which can't fully implement the generic filters. This patch
adds clarification that it is okay to support the specific filters in
SIOCSHWTSTAMP by upscaling them to the generic filters. In addition,
update the header for ethtool_ts_info to specify that drivers ought to
only report the filters they support without upscaling in this manner.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Reviewed-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Documentation/networking/timestamping.txt
include/uapi/linux/ethtool.h