[PATCH] [v2] Input: touchscreen: Fix a missing check on regmap_bulk_read

[Aditya Pakki]

regmap_bulk_read() can return a non zero value on failure. The fix
checks if the function call succeeded before calling mod_timer. The
issue was identified by a static analysis tool.

Signed-off-by: Aditya Pakki <pakki001@xxxxxxx>
---
 drivers/input/touchscreen/ad7879.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/input/touchscreen/ad7879.c b/drivers/input/touchscreen/ad7879.c
index 6fa714c587b4..8c908572c1f2 100644
--- a/drivers/input/touchscreen/ad7879.c
+++ b/drivers/input/touchscreen/ad7879.c
@@ -246,11 +246,14 @@ static void ad7879_timer(struct timer_list *t)
 static irqreturn_t ad7879_irq(int irq, void *handle)
 {
 	struct ad7879 *ts = handle;
+	int error;
 
-	regmap_bulk_read(ts->regmap, AD7879_REG_XPLUS,
-			 ts->conversion_data, AD7879_NR_SENSE);
-
-	if (!ad7879_report(ts))
+	error = regmap_bulk_read(ts->regmap, AD7879_REG_XPLUS,
+					ts->conversion_data, AD7879_NR_SENSE);
+	if (error)
+		dev_err_ratelimited(ts->dev, "failed to read %#02x: %d\n",
+					AD7879_REG_XPLUS, error);
+	else if (!ad7879_report(ts))
 		mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
 
 	return IRQ_HANDLED;
-- 
2.17.1