[PATCH 4.8 04/10] Staging: fbtft: Fix bug in fbtft-core

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

4.8-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>

commit fc1e2c8ea85e109acf09e74789e9b852f6eed251 upstream.

Commit 367e8560e8d7a62d96e9b1d644028a3816e04206 introduced a bug
in fbtft-core where fps is always 0, this is because variable
update_time is not assigned correctly.

Signed-off-by: Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
Fixes: 367e8560e8d7 ("Staging: fbtbt: Replace timespec with ktime_t")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/staging/fbtft/fbtft-core.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -391,11 +391,11 @@ static void fbtft_update_display(struct
 
 	if (unlikely(timeit)) {
 		ts_end = ktime_get();
-		if (ktime_to_ns(par->update_time))
+		if (!ktime_to_ns(par->update_time))
 			par->update_time = ts_start;
 
-		par->update_time = ts_start;
 		fps = ktime_us_delta(ts_start, par->update_time);
+		par->update_time = ts_start;
 		fps = fps ? 1000000 / fps : 0;
 
 		throughput = ktime_us_delta(ts_end, ts_start);