diff --git a/drivers/input/keyboard/tca6416-keypad.c b/drivers/input/keyboard/tca6416-keypad.c
index dc983ab6c0ad..cdeef180aead 100644
--- a/drivers/input/keyboard/tca6416-keypad.c
+++ b/drivers/input/keyboard/tca6416-keypad.c
@@ -219,9 +219,7 @@ static int tca6416_keypad_probe(struct i2c_client *client,
 		return -EINVAL;
 	}
 
-	chip = kzalloc(sizeof(struct tca6416_keypad_chip) +
-		       pdata->nbuttons * sizeof(struct tca6416_button),
-		       GFP_KERNEL);
+	chip = kzalloc(struct_size(chip, buttons, pdata->nbuttons), GFP_KERNEL);
 	input = input_allocate_device();
 	if (!chip || !input) {
 		error = -ENOMEM;