From 763fbaf65a3f7fd571db427a376e727faeb5bfc5 Mon Sep 17 00:00:00 2001 From: Manu Abraham Date: Fri, 18 Jan 2008 11:28:48 -0300 Subject: V4L/DVB (9443): Bug: Bandwidth calculation Bug #1: The 5 tap equaliser is set to correct simple perturbations like reflections on the IF cable for DVB-S. In the case of DVB-S2 a more powerful equalizer is used to correct the filter group delay allowing the bandwidth to be reduced by a factor of 1/3 Bug #2: The ZIF tuner takes badwidth to be set in Hz Signed-off-by: Manu Abraham Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/frontends/stb0899_drv.c | 5 ++--- drivers/media/dvb/frontends/stb6100.c | 2 +- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/media/dvb/frontends/stb0899_drv.c b/drivers/media/dvb/frontends/stb0899_drv.c index d2139645025..45961193272 100644 --- a/drivers/media/dvb/frontends/stb0899_drv.c +++ b/drivers/media/dvb/frontends/stb0899_drv.c @@ -1554,8 +1554,7 @@ static enum dvbfe_search stb0899_search(struct dvb_frontend *fe, struct dvbfe_pa } dprintk(verbose, FE_DEBUG, 1, "delivery system=%d", state->delsys); - SearchRange = 3000000; /* Search Bandwidth (3 Mhz, was initially 10 Mhz) */ -// SearchRange = 10000000; /* Search Bandwidth (3 Mhz, was initially 10 Mhz) */ + SearchRange = 10000000; dprintk(verbose, FE_DEBUG, 1, "Frequency=%d, Srate=%d", i_params->freq, i_params->srate); /* checking Search Range is meaningless for a fixed 3 Mhz */ if (INRANGE(i_params->srate, 1000000, 45000000)) { @@ -1626,7 +1625,7 @@ static enum dvbfe_search stb0899_search(struct dvb_frontend *fe, struct dvbfe_pa internal->srch_range = SearchRange; if (state->config->tuner_set_bandwidth) - state->config->tuner_set_bandwidth(fe, (135 * (stb0899_carr_width(state) + SearchRange)) / 100); + state->config->tuner_set_bandwidth(fe, (stb0899_carr_width(state) + SearchRange)); if (state->config->tuner_get_bandwidth) state->config->tuner_get_bandwidth(fe, &internal->tuner_bw); diff --git a/drivers/media/dvb/frontends/stb6100.c b/drivers/media/dvb/frontends/stb6100.c index d19a3bfcc5f..f4c2b8e114b 100644 --- a/drivers/media/dvb/frontends/stb6100.c +++ b/drivers/media/dvb/frontends/stb6100.c @@ -269,7 +269,7 @@ static int stb6100_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth) dprintk(verbose, FE_DEBUG, 1, "set bandwidth to %u kHz", bandwidth); - bandwidth *= 1000 / 2; /* kHz -> Hz, bw / 2 */ + bandwidth /= 2; /* ZIF */ if (bandwidth > 36000000) /* F[4:0] BW/2 max =31+5=36 mhz for F=31 */ tmp = 31; -- cgit v1.2.3