[media] rtl2832: implement DVBv5 signal strength statistics

Estimate signal strength from IF digital AGC.

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

diff --git a/drivers/media/dvb-frontends/rtl2832.c b/drivers/media/dvb-frontends/rtl2832.c
index 90d4f45d9958ff3f33e59be849b3d94db262da9d..6aaaec2a40c2b7dcc6f874ef8fe12af2dd0e089d 100644 (file)
--- a/drivers/media/dvb-frontends/rtl2832.c
+++ b/drivers/media/dvb-frontends/rtl2832.c
@@ -474,6 +474,8 @@ static int rtl2832_init(struct dvb_frontend *fe)
                goto err;
 #endif
        /* init stats here in order signal app which stats are supported */
+       c->strength.len = 1;
+       c->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
        c->cnr.len = 1;
        c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
        c->post_bit_error.len = 1;
@@ -823,6 +825,24 @@ static void rtl2832_stat_work(struct work_struct *work)
 
        dev_dbg(&client->dev, "\n");
 
+       /* signal strength */
+       if (dev->fe_status & FE_HAS_SIGNAL) {
+               /* read digital AGC */
+               ret = rtl2832_bulk_read(client, 0x305, &u8tmp, 1);
+               if (ret)
+                       goto err;
+
+               dev_dbg(&client->dev, "digital agc=%02x", u8tmp);
+
+               u8tmp = ~u8tmp;
+               u16tmp = u8tmp << 8 | u8tmp << 0;
+
+               c->strength.stat[0].scale = FE_SCALE_RELATIVE;
+               c->strength.stat[0].uvalue = u16tmp;
+       } else {
+               c->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
+       }
+
        /* CNR */
        if (dev->fe_status & FE_HAS_VITERBI) {
                unsigned hierarchy, constellation;