[media] tuner-xc2028: Don't read status if device is powered down

That removes those timeout errors:

[ 3675.930940] xc2028 19-0061: Device is Xceive 3028 version 1.0, firmware version 2.7
[ 3676.060487] xc2028 19-0061: divisor= 00 00 8d d0 (freq=567.250)
[ 3676.349449] xc2028 19-0061: Putting xc2028/3028 into poweroff mode.
[ 3698.247645] xc2028 19-0061: xc2028_get_reg 0002 called
[ 3698.253276] em2860 #0: I2C transfer timeout on writing to addr 0xc2
[ 3698.253301] xc2028 19-0061: i2c input error: rc = -121 (should be 2)
[ 3698.253327] xc2028 19-0061: xc2028_signal called
[ 3698.253339] xc2028 19-0061: xc2028_get_reg 0002 called
[ 3698.259283] em2860 #0: I2C transfer timeout on writing to addr 0xc2
[ 3698.259312] xc2028 19-0061: i2c input error: rc = -121 (should be 2)

Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

drivers/media/tuners/tuner-xc2028.c

@@ -267,6 +267,7 @@ static int check_device_status(struct xc2028_data *priv)
 	case XC2028_WAITING_FIRMWARE:
 		return -EAGAIN;
 	case XC2028_ACTIVE:
+		return 1;
 	case XC2028_SLEEP:
 		return 0;
 	case XC2028_NODEV:
@@ -913,6 +914,12 @@ static int xc2028_signal(struct dvb_frontend *fe, u16 *strength)
 	if (rc < 0)
 		return rc;
 
+	/* If the device is sleeping, no channel is tuned */
+	if (!rc) {
+		*strength = 0;
+		return 0;
+	}
+
 	mutex_lock(&priv->lock);
 
 	/* Sync Lock Indicator */
@@ -960,6 +967,12 @@ static int xc2028_get_afc(struct dvb_frontend *fe, s32 *afc)
 	if (rc < 0)
 		return rc;
 
+	/* If the device is sleeping, no channel is tuned */
+	if (!rc) {
+		*afc = 0;
+		return 0;
+	}
+
 	mutex_lock(&priv->lock);
 
 	/* Sync Lock Indicator */
@@ -1277,12 +1290,12 @@ static int xc2028_sleep(struct dvb_frontend *fe)
 	if (rc < 0)
 		return rc;
 
-	/* Avoid firmware reload on slow devices or if PM disabled */
-	if (no_poweroff || priv->ctrl.disable_power_mgmt)
+	/* Device is already in sleep mode */
+	if (!rc)
 		return 0;
 
-	/* Device is already in sleep mode */
-	if (priv->state == XC2028_SLEEP)
+	/* Avoid firmware reload on slow devices or if PM disabled */
+	if (no_poweroff || priv->ctrl.disable_power_mgmt)
 		return 0;
 
 	tuner_dbg("Putting xc2028/3028 into poweroff mode.\n");