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    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;
    }
    --

    -
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