Messages in this thread Patch in this message | | | Date | Mon, 05 Sep 2005 01:23:11 +0200 | From | Johannes Stezenbach <> | Subject | [DVB patch 12/54] frontend: mt352: fix signal strength reading |
| |
From: Barry Scott <barry.scott@onelan.co.uk>
Fix two problems with the signal strength value in the mt352.c frontend: 1. the 4 most significant bits are zeroed - shift and mask wrong way round 2. need to align the 12 bits from the registers at the top of the 16 bit returned value - otherwise the range is not 0 to 0xffff its 0xf000 to 0xffff
Signed-off-by: Barry Scott <barry.scott@onelan.co.uk> Signed-off-by: Johannes Stezenbach <js@linuxtv.org>
drivers/media/dvb/frontends/mt352.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- linux-2.6.13-git4.orig/drivers/media/dvb/frontends/mt352.c 2005-09-04 22:24:24.000000000 +0200 +++ linux-2.6.13-git4/drivers/media/dvb/frontends/mt352.c 2005-09-04 22:28:02.000000000 +0200 @@ -462,9 +462,11 @@ static int mt352_read_signal_strength(st { struct mt352_state* state = fe->demodulator_priv; - u16 signal = ((mt352_read_register(state, AGC_GAIN_1) << 8) & 0x0f) | - (mt352_read_register(state, AGC_GAIN_0)); + /* align the 12 bit AGC gain with the most significant bits */ + u16 signal = ((mt352_read_register(state, AGC_GAIN_1) & 0x0f) << 12) | + (mt352_read_register(state, AGC_GAIN_0) << 4); + /* inverse of gain is signal strength */ *strength = ~signal; return 0; } --
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |