[media] rtl2830: wrap DVBv5 signal strength to DVBv3

Change legacy DVBv3 signal strength to return values calculated by
DVBv5 statistics.

Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>

drivers/media/dvb-frontends/rtl2830.c

@@ -623,33 +623,14 @@ static int rtl2830_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
 
 static int rtl2830_read_signal_strength(struct dvb_frontend *fe, u16 *strength)
 {
-	struct i2c_client *client = fe->demodulator_priv;
-	struct rtl2830_dev *dev = i2c_get_clientdata(client);
-	int ret;
-	u8 buf[2];
-	u16 if_agc_raw, if_agc;
-
-	if (dev->sleeping)
-		return 0;
-
-	ret = rtl2830_rd_regs(client, 0x359, buf, 2);
-	if (ret)
-		goto err;
-
-	if_agc_raw = (buf[0] << 8 | buf[1]) & 0x3fff;
+	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 
-	if (if_agc_raw & (1 << 9))
-		if_agc = -(~(if_agc_raw - 1) & 0x1ff);
+	if (c->strength.stat[0].scale == FE_SCALE_RELATIVE)
+		*strength = c->strength.stat[0].uvalue;
 	else
-		if_agc = if_agc_raw;
-
-	*strength = (u8)(55 - if_agc / 182);
-	*strength |= *strength << 8;
+		*strength = 0;
 
 	return 0;
-err:
-	dev_dbg(&client->dev, "failed=%d\n", ret);
-	return ret;
 }
 
 static struct dvb_frontend_ops rtl2830_ops = {