[PATCH net-next] Let the ADJ_OFFSET interface respect the STA_NANO flag for PHC devices.

[Richard Cochran]

In commit 184ecc9eb260d5a3bcdddc5bebd18f285ac004e9 ("ptp: Add adjphase
function to support phase offset control.")  the PTP Hardware Clock
interface expanded to support the ADJ_OFFSET offset mode.  However,
the implementation did not respect the traditional yet pedantic
distinction between units of microseconds and nanoseconds signaled by
the STA_NANO flag.  This patch fixes the issue by adding logic to
handle that flag.

Signed-off-by: Richard Cochran <richardcoch...@gmail.com>
---
 drivers/ptp/ptp_clock.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index fc984a8828fb..7ae6e8e85f99 100644
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -147,8 +147,13 @@ static int ptp_clock_adjtime(struct posix_clock *pc, 
struct __kernel_timex *tx)
                        err = ops->adjfreq(ops, ppb);
                ptp->dialed_frequency = tx->freq;
        } else if (tx->modes & ADJ_OFFSET) {
-               if (ops->adjphase)
-                       err = ops->adjphase(ops, tx->offset);
+               if (ops->adjphase) {
+                       s32 offset = tx->offset;
+                       if (!(tx->status & STA_NANO)) {
+                               offset *= NSEC_PER_USEC;
+                       }
+                       err = ops->adjphase(ops, offset);
+               }
        } else if (tx->modes == 0) {
                tx->freq = ptp->dialed_frequency;
                err = 0;
-- 
2.20.1