From 796c1efd6fa0ed696d550b68f4410ab1a1749d01 Mon Sep 17 00:00:00 2001 From: Richard Cochran Date: Sun, 21 Dec 2014 19:46:57 +0100 Subject: [PATCH] timecounter: provide a helper function to shift the time. MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Some PTP Hardware Clock drivers use a struct timecounter to represent their clock. To adjust the time by a given offset, these drivers all perform a two step read/write of their timecounter. However, it is better and simpler just to adjust the offset in one step. This patch introduces a little routine to help drivers implement the adjtime method. Suggested-by: Janusz Użycki Signed-off-by: Richard Cochran Signed-off-by: David S. Miller --- include/linux/timecounter.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/timecounter.h b/include/linux/timecounter.h index 146f07a6651b..af3dfa4e90f0 100644 --- a/include/linux/timecounter.h +++ b/include/linux/timecounter.h @@ -78,6 +78,15 @@ static inline u64 cyclecounter_cyc2ns(const struct cyclecounter *cc, return ret; } +/** + * timecounter_adjtime - Shifts the time of the clock. + * @delta: Desired change in nanoseconds. + */ +static inline void timecounter_adjtime(struct timecounter *tc, s64 delta) +{ + tc->nsec += delta; +} + /** * timecounter_init - initialize a time counter * @tc: Pointer to time counter which is to be initialized/reset -- 2.30.2