ntp: support for TAI
This adds support for setting the TAI value (International Atomic Time). The
value is reported back to userspace via timex (as we don't have a
ntp_gettime() syscall).
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 44491de..10fe17d 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -35,6 +35,7 @@
/* TIME_ERROR prevents overwriting the CMOS clock */
static int time_state = TIME_OK; /* clock synchronization status */
int time_status = STA_UNSYNC; /* clock status bits */
+static long time_tai; /* TAI offset (s) */
static s64 time_offset; /* time adjustment (ns) */
static long time_constant = 2; /* pll time constant */
long time_maxerror = NTP_PHASE_LIMIT; /* maximum error (us) */
@@ -162,6 +163,7 @@
case TIME_DEL:
if ((xtime.tv_sec + 1) % 86400 == 0) {
xtime.tv_sec++;
+ time_tai--;
wall_to_monotonic.tv_sec--;
time_state = TIME_WAIT;
printk(KERN_NOTICE "Clock: deleting leap second "
@@ -169,6 +171,7 @@
}
break;
case TIME_OOP:
+ time_tai++;
time_state = TIME_WAIT;
break;
case TIME_WAIT:
@@ -340,6 +343,9 @@
time_constant = max(time_constant, 0l);
}
+ if (txc->modes & ADJ_TAI && txc->constant > 0)
+ time_tai = txc->constant;
+
if (txc->modes & ADJ_OFFSET) {
if (txc->modes == ADJ_OFFSET_SINGLESHOT)
/* adjtime() is independent from ntp_adjtime() */
@@ -377,6 +383,7 @@
txc->precision = 1;
txc->tolerance = MAXFREQ_SCALED / PPM_SCALE;
txc->tick = tick_usec;
+ txc->tai = time_tai;
/* PPS is not implemented, so these are zero */
txc->ppsfreq = 0;