From: Mauro Carvalho Chehab Date: Mon, 14 Sep 2020 13:17:18 +0000 (+0200) Subject: media: vidtv: adjust signal strength range X-Git-Tag: v5.10.7~1469^2~213 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=d859a712a378a4f81c387f2afdee437a6a0a6b54;p=platform%2Fkernel%2Flinux-rpi.git media: vidtv: adjust signal strength range On real devices, signal strength is always a negative number when represented in dBm. A more interesting range is to use dBmV (which is what Kaffeine does, for example). The conversion from the two units are simple: dBmV = dBm - 108 Usually, signal strength ranges up to 100dBmV. Adjust the maximum value to be around 74 dBmV, when there's no frequency shift, which represents a good signal. With that, Kaffeine displays it a lot better. Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/test-drivers/vidtv/vidtv_demod.c b/drivers/media/test-drivers/vidtv/vidtv_demod.c index c54c88c..c825842 100644 --- a/drivers/media/test-drivers/vidtv/vidtv_demod.c +++ b/drivers/media/test-drivers/vidtv/vidtv_demod.c @@ -181,12 +181,18 @@ static void vidtv_demod_update_stats(struct dvb_frontend *fe) c->block_count.stat[0].scale = scale; /* - * Add a 0.5% of randomness at the signal streangth and CNR, + * Add a 0.5% of randomness at the signal strength and CNR, * and make them different, as we want to have something closer * to a real case scenario. + * + * Also, usually, signal strength is a negative number in dBm. */ - c->strength.stat[0].svalue = state->tuner_cnr + prandom_u32_max(state->tuner_cnr / 50); - c->cnr.stat[0].svalue = state->tuner_cnr - prandom_u32_max(state->tuner_cnr / 50); + c->strength.stat[0].svalue = state->tuner_cnr; + c->strength.stat[0].svalue -= prandom_u32_max(state->tuner_cnr / 50); + c->strength.stat[0].svalue -= 68000; /* Adjust to a better range */ + + c->cnr.stat[0].svalue = state->tuner_cnr; + c->cnr.stat[0].svalue -= prandom_u32_max(state->tuner_cnr / 50); }