Input: wm97xx-core - use IRQF_SAMPLE_RANDOM

The touchscreen interrupt is driven by human input which can reasonably
be used to provide entropy.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/wm97xx-core.c b/drivers/input/touchscreen/wm97xx-core.c
index e27b1e0..fec07c2 100644
--- a/drivers/input/touchscreen/wm97xx-core.c
+++ b/drivers/input/touchscreen/wm97xx-core.c
@@ -355,7 +355,8 @@
 	 * provided. */
 	BUG_ON(!wm->mach_ops->irq_enable);
 
-	if (request_irq(wm->pen_irq, wm97xx_pen_interrupt, IRQF_SHARED,
+	if (request_irq(wm->pen_irq, wm97xx_pen_interrupt,
+			IRQF_SHARED | IRQF_SAMPLE_RANDOM,
 			"wm97xx-pen", wm)) {
 		dev_err(wm->dev,
 			"Failed to register pen down interrupt, polling");