media: dvb: mb86a16: check the return value of mb86a16_read()

return an error code if mb86a16_read() gets an unexpected return
value.
Signed-off-by: Yuanjun Gong <ruc_gongyuanjun@163.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
[hverkuil: add {} around the else statement]

drivers/media/dvb-frontends/mb86a16.c

@@ -1487,10 +1487,12 @@ static int mb86a16_set_fe(struct mb86a16_state *state)
 		}
 	}
 
-	mb86a16_read(state, 0x15, &agcval);
-	mb86a16_read(state, 0x26, &cnmval);
-	dprintk(verbose, MB86A16_INFO, 1, "AGC = %02x CNM = %02x", agcval, cnmval);
-
+	if (mb86a16_read(state, 0x15, &agcval) != 2 ||	mb86a16_read(state, 0x26, &cnmval) != 2) {
+		dprintk(verbose, MB86A16_ERROR, 1, "I2C transfer error");
+		ret = -EREMOTEIO;
+	} else {
+		dprintk(verbose, MB86A16_INFO, 1, "AGC = %02x CNM = %02x", agcval, cnmval);
+	}
 	return ret;
 }