media: lgdt3306a: Add CNR v5 stat

The CNR is already calculated, so populate DVBv5 CNR stat
during read_status.

Signed-off-by: Brad Love <brad@nextdimension.cc>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/dvb-frontends/lgdt3306a.c

@@ -846,6 +846,7 @@ static int lgdt3306a_fe_sleep(struct dvb_frontend *fe)
 static int lgdt3306a_init(struct dvb_frontend *fe)
 {
 	struct lgdt3306a_state *state = fe->demodulator_priv;
+	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 	u8 val;
 	int ret;
 
@@ -997,6 +998,9 @@ static int lgdt3306a_init(struct dvb_frontend *fe)
 	ret = lgdt3306a_sleep(state);
 	lg_chkerr(ret);
 
+	c->cnr.len = 1;
+	c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+
 fail:
 	return ret;
 }
@@ -1597,6 +1601,7 @@ static int lgdt3306a_read_status(struct dvb_frontend *fe,
 				 enum fe_status *status)
 {
 	struct lgdt3306a_state *state = fe->demodulator_priv;
+	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 	u16 strength = 0;
 	int ret = 0;
 
@@ -1637,6 +1642,15 @@ static int lgdt3306a_read_status(struct dvb_frontend *fe,
 		default:
 			ret = -EINVAL;
 		}
+
+		if (*status & FE_HAS_SYNC) {
+			c->cnr.len = 1;
+			c->cnr.stat[0].scale = FE_SCALE_DECIBEL;
+			c->cnr.stat[0].svalue = lgdt3306a_calculate_snr_x100(state) * 10;
+		} else {
+			c->cnr.len = 1;
+			c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+		}
 	}
 	return ret;
 }