[media] cxd2820r: dvbv5 statistics for DVB-T2

Implement dvbv5 statistics for DVB-T2.
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

drivers/media/dvb-frontends/cxd2820r_t2.c

@@ -286,8 +286,10 @@ int cxd2820r_get_frontend_t2(struct dvb_frontend *fe,
 int cxd2820r_read_status_t2(struct dvb_frontend *fe, enum fe_status *status)
 {
 	struct cxd2820r_priv *priv = fe->demodulator_priv;
+	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 	int ret;
-	u8 buf[1];
+	unsigned int utmp;
+	u8 buf[4];
 	*status = 0;
 
 	ret = cxd2820r_rd_reg(priv, 0x02010 , &buf[0]);
@@ -306,6 +308,79 @@ int cxd2820r_read_status_t2(struct dvb_frontend *fe, enum fe_status *status)
 
 	dev_dbg(&priv->i2c->dev, "%s: lock=%02x\n", __func__, buf[0]);
 
+	/* Signal strength */
+	if (*status & FE_HAS_SIGNAL) {
+		unsigned int strength;
+
+		ret = cxd2820r_rd_regs(priv, 0x02026, buf, 2);
+		if (ret)
+			goto error;
+
+		utmp = buf[0] << 8 | buf[1] << 0;
+		utmp = ~utmp & 0x0fff;
+		/* Scale value to 0x0000-0xffff */
+		strength = utmp << 4 | utmp >> 8;
+
+		c->strength.len = 1;
+		c->strength.stat[0].scale = FE_SCALE_RELATIVE;
+		c->strength.stat[0].uvalue = strength;
+	} else {
+		c->strength.len = 1;
+		c->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+	}
+
+	/* CNR */
+	if (*status & FE_HAS_VITERBI) {
+		unsigned int cnr;
+
+		ret = cxd2820r_rd_regs(priv, 0x02028, buf, 2);
+		if (ret)
+			goto error;
+
+		utmp = buf[0] << 8 | buf[1] << 0;
+		utmp = utmp & 0x0fff;
+		#define CXD2820R_LOG10_8_24 15151336 /* log10(8) << 24 */
+		if (utmp)
+			cnr = div_u64((u64)(intlog10(utmp)
+				      - CXD2820R_LOG10_8_24) * 10000,
+				      (1 << 24));
+		else
+			cnr = 0;
+
+		c->cnr.len = 1;
+		c->cnr.stat[0].scale = FE_SCALE_DECIBEL;
+		c->cnr.stat[0].svalue = cnr;
+	} else {
+		c->cnr.len = 1;
+		c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+	}
+
+	/* BER */
+	if (*status & FE_HAS_SYNC) {
+		unsigned int post_bit_error;
+
+		ret = cxd2820r_rd_regs(priv, 0x02039, buf, 4);
+		if (ret)
+			goto error;
+
+		if ((buf[0] >> 4) & 0x01) {
+			post_bit_error = buf[0] << 24 | buf[1] << 16 |
+					 buf[2] << 8 | buf[3] << 0;
+			post_bit_error &= 0x0fffffff;
+		} else {
+			post_bit_error = 0;
+		}
+
+		priv->post_bit_error += post_bit_error;
+
+		c->post_bit_error.len = 1;
+		c->post_bit_error.stat[0].scale = FE_SCALE_COUNTER;
+		c->post_bit_error.stat[0].uvalue = priv->post_bit_error;
+	} else {
+		c->post_bit_error.len = 1;
+		c->post_bit_error.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+	}
+
 	return ret;
 error:
 	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);