diff options
| author | Antti Palosaari <crope@iki.fi> | 2015-03-26 14:49:17 +0100 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@osg.samsung.com> | 2015-06-10 15:55:58 +0200 |
| commit | 2ca58f45cc986952dc2b2942fb170d9d7644735a (patch) | |
| tree | d6de2e07785dedcc983047b6e6f4e5ef368d0f18 /drivers/media | |
| parent | [media] ts2020: re-implement PLL calculations (diff) | |
| download | linux-2ca58f45cc986952dc2b2942fb170d9d7644735a.tar.xz linux-2ca58f45cc986952dc2b2942fb170d9d7644735a.zip | |
[media] ts2020: improve filter limit calc
* We don't need calculate channel bandwidth from symbol rate as it
is calculated by DVB core.
* Use clamp() to force upper/lower limit of filter 3dB frequency.
Upper limit should never exceeded 40MHz (80MHz BW) in any case,
though...
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/dvb-frontends/ts2020.c | 10 |
1 files changed, 3 insertions, 7 deletions
diff --git a/drivers/media/dvb-frontends/ts2020.c b/drivers/media/dvb-frontends/ts2020.c index bc48388906d3..590f7e1b56f3 100644 --- a/drivers/media/dvb-frontends/ts2020.c +++ b/drivers/media/dvb-frontends/ts2020.c @@ -233,7 +233,6 @@ static int ts2020_set_params(struct dvb_frontend *fe) struct dtv_frontend_properties *c = &fe->dtv_property_cache; struct ts2020_priv *priv = fe->tuner_priv; int ret; - u32 symbol_rate = (c->symbol_rate / 1000); u32 f3db, gdiv28; u16 u16tmp, value, lpf_coeff; u8 buf[3], reg10, lpf_mxdiv, mlpf_max, mlpf_min, nlpf; @@ -312,12 +311,9 @@ static int ts2020_set_params(struct dvb_frontend *fe) value = ts2020_readreg(fe, 0x26); - f3db = (symbol_rate * 135) / 200 + 2000; - f3db += FREQ_OFFSET_LOW_SYM_RATE; - if (f3db < 7000) - f3db = 7000; - if (f3db > 40000) - f3db = 40000; + f3db = (c->bandwidth_hz / 1000 / 2) + 2000; + f3db += FREQ_OFFSET_LOW_SYM_RATE; /* FIXME: ~always too wide filter */ + f3db = clamp(f3db, 7000U, 40000U); gdiv28 = gdiv28 * 207 / (value * 2 + 151); mlpf_max = gdiv28 * 135 / 100; |