[PATCH] Input: smtpe-ts: Use msecs_to_jiffies() instead of HZ

[Marek Vasut <marex@denx.de>]

Use msecs_to_jiffies(50) instead of plain (HZ / 50) as the
former is independent of kernel HZ settings and provides
stable delay.

The delay here must be stable, otherwise we might start polling
for pen-up event too early. This would in turn render the
touchscreen unusable.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Vipul Kumar Samar <vipulkumar.samar@st.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Dmitry Torokhov <dmitry.torokhov@gmail.com>
---
 drivers/input/touchscreen/stmpe-ts.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

NOTE: This applies all the way back to Linux ~2.6.36, so I should
      probably also submit this for -stable if acceptable ?

diff --git a/drivers/input/touchscreen/stmpe-ts.c b/drivers/input/touchscreen/stmpe-ts.c
index 42ce31a..a8f5ea7 100644
--- a/drivers/input/touchscreen/stmpe-ts.c
+++ b/drivers/input/touchscreen/stmpe-ts.c
@@ -164,7 +164,7 @@ static irqreturn_t stmpe_ts_handler(int irq, void *data)
 			STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN);
 
 	/* start polling for touch_det to detect release */
-	schedule_delayed_work(&ts->work, HZ / 50);
+	schedule_delayed_work(&ts->work, msecs_to_jiffies(50));
 
 	return IRQ_HANDLED;
 }
-- 
2.1.4