media: dvb-frontends/stv0367: DVB-C signal strength statistics

Provide QAM/DVB-C signal strength in decibel scale. Values returned from
stv0367cab_get_rf_lvl() are good but need to be multiplied as they're in
1dBm precision.

Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>

diff --git a/drivers/media/dvb-frontends/stv0367.c b/drivers/media/dvb-frontends/stv0367.c
index 1983c87d7d22cc0ecf7139521e474c817b4b6d60..fab94341c22bdb91556e393493460ba538356389 100644 (file)
--- a/drivers/media/dvb-frontends/stv0367.c
+++ b/drivers/media/dvb-frontends/stv0367.c
@@ -2998,6 +2998,25 @@ static int stv0367ddb_set_frontend(struct dvb_frontend *fe)
        return -EINVAL;
 }
 
+static void stv0367ddb_read_signal_strength(struct dvb_frontend *fe)
+{
+       struct stv0367_state *state = fe->demodulator_priv;
+       struct dtv_frontend_properties *p = &fe->dtv_property_cache;
+       s32 signalstrength;
+
+       switch (state->activedemod) {
+       case demod_cab:
+               signalstrength = stv0367cab_get_rf_lvl(state) * 1000;
+               break;
+       default:
+               p->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+               return;
+       }
+
+       p->strength.stat[0].scale = FE_SCALE_DECIBEL;
+       p->strength.stat[0].uvalue = signalstrength;
+}
+
 static void stv0367ddb_read_snr(struct dvb_frontend *fe)
 {
        struct stv0367_state *state = fe->demodulator_priv;
@@ -3075,6 +3094,8 @@ static int stv0367ddb_read_status(struct dvb_frontend *fe,
        if (ret)
                return ret;
 
+       stv0367ddb_read_signal_strength(fe);
+
        /* read carrier/noise when a carrier is detected */
        if (*status & FE_HAS_CARRIER)
                stv0367ddb_read_snr(fe);