ptp: add gettimex64() to virtual clocks.

If the physical clock has the gettimex64() function, provide a
gettimex64() wrapper in the virtual clock to enable more accurate
and stable synchronization.

This adds support for the PTP_SYS_OFFSET_EXTENDED ioctl.

Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Cc: Yangbo Lu <yangbo.lu@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/ptp/ptp_vclock.c b/drivers/ptp/ptp_vclock.c
index 5aa2b32..2f0b463 100644 (file)
--- a/drivers/ptp/ptp_vclock.c
+++ b/drivers/ptp/ptp_vclock.c
@@ -57,6 +57,30 @@ static int ptp_vclock_gettime(struct ptp_clock_info *ptp,
        return 0;
 }
 
+static int ptp_vclock_gettimex(struct ptp_clock_info *ptp,
+                              struct timespec64 *ts,
+                              struct ptp_system_timestamp *sts)
+{
+       struct ptp_vclock *vclock = info_to_vclock(ptp);
+       struct ptp_clock *pptp = vclock->pclock;
+       struct timespec64 pts;
+       unsigned long flags;
+       int err;
+       u64 ns;
+
+       err = pptp->info->gettimex64(pptp->info, &pts, sts);
+       if (err)
+               return err;
+
+       spin_lock_irqsave(&vclock->lock, flags);
+       ns = timecounter_cyc2time(&vclock->tc, timespec64_to_ns(&pts));
+       spin_unlock_irqrestore(&vclock->lock, flags);
+
+       *ts = ns_to_timespec64(ns);
+
+       return 0;
+}
+
 static int ptp_vclock_settime(struct ptp_clock_info *ptp,
                              const struct timespec64 *ts)
 {
@@ -87,7 +111,6 @@ static const struct ptp_clock_info ptp_vclock_info = {
        .max_adj        = 500000000,
        .adjfine        = ptp_vclock_adjfine,
        .adjtime        = ptp_vclock_adjtime,
-       .gettime64      = ptp_vclock_gettime,
        .settime64      = ptp_vclock_settime,
        .do_aux_work    = ptp_vclock_refresh,
 };
@@ -123,6 +146,10 @@ struct ptp_vclock *ptp_vclock_register(struct ptp_clock *pclock)
 
        vclock->pclock = pclock;
        vclock->info = ptp_vclock_info;
+       if (pclock->info->gettimex64)
+               vclock->info.gettimex64 = ptp_vclock_gettimex;
+       else
+               vclock->info.gettime64 = ptp_vclock_gettime;
        vclock->cc = ptp_vclock_cc;
 
        snprintf(vclock->info.name, PTP_CLOCK_NAME_LEN, "ptp%d_virt",