mfd: fix event masking for da9030

Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
diff --git a/drivers/mfd/da903x.c b/drivers/mfd/da903x.c
index b57326a..0b5bd85 100644
--- a/drivers/mfd/da903x.c
+++ b/drivers/mfd/da903x.c
@@ -267,7 +267,7 @@
 {
 	uint8_t v[3];
 
-	chip->events_mask &= ~events;
+	chip->events_mask |= events;
 
 	v[0] = (chip->events_mask & 0xff);
 	v[1] = (chip->events_mask >> 8) & 0xff;