From 5c75e501d34b4cfe7d345105b1b48d7c526f0e97 Mon Sep 17 00:00:00 2001
From: Athanasios Oikonomou <athoik@gmail.com>
Date: Mon, 8 Feb 2016 22:14:31 +0200
Subject: [PATCH] STV: Add SNR/Signal report parameters


diff --git a/drivers/media/dvb-frontends/stv090x.c b/drivers/media/dvb-frontends/stv090x.c
index 416b749..9639500 100644
--- a/drivers/media/dvb-frontends/stv090x.c
+++ b/drivers/media/dvb-frontends/stv090x.c
@@ -38,6 +38,18 @@
 static unsigned int verbose;
 module_param(verbose, int, 0644);
 
+/* define how SNR measurement is reported */
+static int esno;
+module_param(esno, int, 0644);
+MODULE_PARM_DESC(esno, "SNR is reported in 0:Percentage, "\
+	"1:(EsNo dB)*10 (default:0)");
+
+/* define how signal measurement is reported */
+static int dbm;
+module_param(dbm, int, 0644);
+MODULE_PARM_DESC(dbm, "Signal is reported in 0:Percentage, "\
+	"1:-1*dBm (default:0)");
+
 /* internal params node */
 struct stv090x_dev {
 	/* pointer for internal params, one for each pair of demods */
@@ -3670,7 +3682,10 @@ static int stv090x_read_signal_strength(struct dvb_frontend *fe, u16 *strength)
 		str = 0;
 	else if (agc < stv090x_rf_tab[ARRAY_SIZE(stv090x_rf_tab) - 1].read)
 		str = -100;
-	*strength = (str + 100) * 0xFFFF / 100;
+	if (dbm)
+		*strength = -str;
+	else
+		*strength = (str + 100) * 0xFFFF / 100;
 
 	return 0;
 }
@@ -3681,8 +3696,7 @@ static int stv090x_read_cnr(struct dvb_frontend *fe, u16 *cnr)
 	u32 reg_0, reg_1, reg, i;
 	s32 val_0, val_1, val = 0;
 	u8 lock_f;
-	s32 div;
-	u32 last;
+	s32 snr;
 
 	switch (state->delsys) {
 	case STV090x_DVBS2:
@@ -3699,10 +3713,14 @@ static int stv090x_read_cnr(struct dvb_frontend *fe, u16 *cnr)
 				msleep(1);
 			}
 			val /= 16;
-			last = ARRAY_SIZE(stv090x_s2cn_tab) - 1;
-			div = stv090x_s2cn_tab[0].read -
-			      stv090x_s2cn_tab[last].read;
-			*cnr = 0xFFFF - ((val * 0xFFFF) / div);
+			snr = stv090x_table_lookup(stv090x_s2cn_tab,
+				ARRAY_SIZE(stv090x_s2cn_tab) - 1, val);
+			if (snr < 0) snr = 0;
+			if (snr > 200) snr = 200;
+			if (esno)
+				*cnr = snr;
+			else
+				*cnr = snr * 0xFFFF / 200;
 		}
 		break;
 
@@ -3721,10 +3739,14 @@ static int stv090x_read_cnr(struct dvb_frontend *fe, u16 *cnr)
 				msleep(1);
 			}
 			val /= 16;
-			last = ARRAY_SIZE(stv090x_s1cn_tab) - 1;
-			div = stv090x_s1cn_tab[0].read -
-			      stv090x_s1cn_tab[last].read;
-			*cnr = 0xFFFF - ((val * 0xFFFF) / div);
+			snr = stv090x_table_lookup(stv090x_s1cn_tab,
+				ARRAY_SIZE(stv090x_s1cn_tab) - 1, val);
+			if (snr < 0) snr = 0;
+			if (snr > 200) snr = 200;
+			if (esno)
+				*cnr = snr;
+			else
+				*cnr = snr * 0xFFFF / 200;
 		}
 		break;
 	default:
-- 
2.1.4