Commit d8d26354 authored by Committed by David S. MillerBrowse files
ptp: Introduce a high resolution frequency adjustment method.
The internal PTP Hardware Clock (PHC) interface limits the resolution for frequency adjustments to one part per billion. However, some hardware devices allow finer adjustment, and making use of the increased resolution improves synchronization measurably on such devices. This patch adds an alternative method that allows finer frequency tuning by passing the scaled ppm value to PHC drivers. This value comes from user space, and it has a resolution of about 0.015 ppb. We also deprecate the older method, anticipating its removal once existing drivers have been converted over. Signed-off-by: Richard Cochran <firstname.lastname@example.org> Suggested-by: Ulrik De Bie <email@example.com> Signed-off-by: David S. Miller <firstname.lastname@example.org>