Input: cy8ctmg110_ts - fix checking return value of i2c_master_send

i2c_master_send returns negative errno, or else the number of bytes written.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/touchscreen/cy8ctmg110_ts.c b/drivers/input/touchscreen/cy8ctmg110_ts.c
index a93c5c2..b3fdd13 100644
--- a/drivers/input/touchscreen/cy8ctmg110_ts.c
+++ b/drivers/input/touchscreen/cy8ctmg110_ts.c
@@ -84,9 +84,9 @@
 	memcpy(i2c_data + 1, value, len);
 
 	ret = i2c_master_send(client, i2c_data, len + 1);
-	if (ret != 1) {
+	if (ret != len + 1) {
 		dev_err(&client->dev, "i2c write data cmd failed\n");
-		return ret ? ret : -EIO;
+		return ret < 0 ? ret : -EIO;
 	}
 
 	return 0;