From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Cochran Subject: [PATCH net-next 02/11] timecounter: provide a helper function to shift the time. Date: Sun, 21 Dec 2014 19:46:57 +0100 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: , Amir Vadai , Ariel Elior , Carolyn Wyborny , David Miller , Frank Li , Jeff Kirsher , John Stultz , Matthew Vick , Miroslav Lichvar , Mugunthan V N , Or Gerlitz , Thomas Gleixner , Tom Lendacky To: Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org 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 U=C5=BCycki Signed-off-by: Richard Cochran --- include/linux/timecounter.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/timecounter.h b/include/linux/timecounter.h index 146f07a..af3dfa4 100644 --- a/include/linux/timecounter.h +++ b/include/linux/timecounter.h @@ -79,6 +79,15 @@ static inline u64 cyclecounter_cyc2ns(const struct c= yclecounter *cc, } =20 /** + * timecounter_adjtime - Shifts the time of the clock. + * @delta: Desired change in nanoseconds. + */ +static inline void timecounter_adjtime(struct timecounter *tc, s64 del= ta) +{ + tc->nsec +=3D delta; +} + +/** * timecounter_init - initialize a time counter * @tc: Pointer to time counter which is to be initialized/reset * @cc: A cycle counter, ready to be used. --=20 1.7.10.4