Input: hil_mlc - convert timeval to jiffies

struct timeval is not y2038 safe, and what mlc->instart do is
scheduling a task in a fixed timeout, so jiffies is the
simplest choice here.

In hilse_donode(), the expires in mod_timer equals

	jiffies + intimeout - (now - instart)

If we use jiffies in 'now', the expires equals

	instart + intimeout

So, all we need to do is that making sure expires is a future
timestamp before passed it to mod_timer.

[arnd: slightly simplified patch further]

Link: https://lists.linaro.org/pipermail/y2038/2015-October/000937.html
Signed-off-by: WEN Pingbo <pingbo.wen@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Patchwork-Id: 10076615
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 7 insertions, 11 deletions

diff --git a/drivers/input/serio/hil_mlc.c b/drivers/input/serio/hil_mlc.c
index 581e47119363..e1423f7648d6 100644
--- a/drivers/input/serio/hil_mlc.c
+++ b/drivers/input/serio/hil_mlc.c
@@ -602,8 +602,8 @@ static inline void hilse_setup_input(hil_mlc *mlc, const struct hilse_node *node
 		BUG();
 	}
 	mlc->istarted = 1;
-	mlc->intimeout = node->arg;
-	do_gettimeofday(&(mlc->instart));
+	mlc->intimeout = usecs_to_jiffies(node->arg);
+	mlc->instart = jiffies;
 	mlc->icount = 15;
 	memset(mlc->ipacket, 0, 16 * sizeof(hil_packet));
 	BUG_ON(down_trylock(&mlc->isem));
@@ -708,7 +708,7 @@ static int hilse_donode(hil_mlc *mlc)
 			break;
 		}
 		mlc->ostarted = 0;
-		do_gettimeofday(&(mlc->instart));
+		mlc->instart = jiffies;
 		write_unlock_irqrestore(&mlc->lock, flags);
 		nextidx = HILSEN_NEXT;
 		break;
@@ -729,18 +729,14 @@ static int hilse_donode(hil_mlc *mlc)
 #endif
 
 	while (nextidx & HILSEN_SCHED) {
-		struct timeval tv;
+		unsigned long now = jiffies;
 
 		if (!sched_long)
 			goto sched;
 
-		do_gettimeofday(&tv);
-		tv.tv_usec += USEC_PER_SEC * (tv.tv_sec - mlc->instart.tv_sec);
-		tv.tv_usec -= mlc->instart.tv_usec;
-		if (tv.tv_usec >= mlc->intimeout) goto sched;
-		tv.tv_usec = (mlc->intimeout - tv.tv_usec) * HZ / USEC_PER_SEC;
-		if (!tv.tv_usec) goto sched;
-		mod_timer(&hil_mlcs_kicker, jiffies + tv.tv_usec);
+		if (time_after(now, mlc->instart + mlc->intimeout))
+			 goto sched;
+		mod_timer(&hil_mlcs_kicker, mlc->instart + mlc->intimeout);
 		break;
 	sched:
 		tasklet_schedule(&hil_mlcs_tasklet);