redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

V4L/DVB (9443): Bug: Bandwidth calculation

Browse source 
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 <manu@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Manu Abraham 2008-01-18 11:28:48 -03:00 committed by Mauro Carvalho Chehab
parent 27a330d124
commit 763fbaf65a
2 changed files with 3 additions and 4 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

5
drivers/media/dvb/frontends/stb0899_drv.c
View file

@ -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);

2
drivers/media/dvb/frontends/stb6100.c
View file

@ -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;