[media] si2168: add I2C error handling

Return error from si2168_cmd_execute in case the demodulator returns an
error.

Signed-off-by: Olli Salonen <olli.salonen@iki.fi>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
diff --git a/drivers/media/dvb-frontends/si2168.c b/drivers/media/dvb-frontends/si2168.c
index 29a5936..b68ab34 100644
--- a/drivers/media/dvb-frontends/si2168.c
+++ b/drivers/media/dvb-frontends/si2168.c
@@ -60,6 +60,12 @@
 				jiffies_to_msecs(jiffies) -
 				(jiffies_to_msecs(timeout) - TIMEOUT));
 
+		/* error bit set? */
+		if ((cmd->args[0] >> 6) & 0x01) {
+			ret = -EREMOTEIO;
+			goto err_mutex_unlock;
+		}
+
 		if (!((cmd->args[0] >> 7) & 0x01)) {
 			ret = -ETIMEDOUT;
 			goto err_mutex_unlock;