struct tuner_params
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## Name

struct tuner_params — Parameters to be used to setup the tuner. Those are used by drivers/media/tuners/tuner-types.c in order to specify the tuner properties. Most of the parameters are for tuners based on tda9887 IF-PLL multi-standard analog TV/Radio demodulator, with is very common on legacy analog tuners.

## Synopsis

    struct tuner_params {
      enum param_type type;
      unsigned int cb_first_if_lower_freq:1;
      unsigned int has_tda9887:1;
      unsigned int port1_fm_high_sensitivity:1;
      unsigned int port2_fm_high_sensitivity:1;
      unsigned int fm_gain_normal:1;
      unsigned int intercarrier_mode:1;
      unsigned int port1_active:1;
      unsigned int port2_active:1;
      unsigned int port1_invert_for_secam_lc:1;
      unsigned int port2_invert_for_secam_lc:1;
      unsigned int port1_set_for_fm_mono:1;
      unsigned int default_pll_gating_18:1;
      unsigned int radio_if:2;
      signed int default_top_low:5;
      signed int default_top_mid:5;
      signed int default_top_high:5;
      signed int default_top_secam_low:5;
      signed int default_top_secam_mid:5;
      signed int default_top_secam_high:5;
      u16 iffreq;
      unsigned int count;
      struct tuner_range * ranges;
    };

## Members

type

  Type of the tuner parameters, as defined at enum param_type. If the tuner supports multiple standards, an array should be used, with one row per different standard.

cb_first_if_lower_freq

  Many Philips-based tuners have a comment in their datasheet like “For channel selection involving band switching, and to ensure smooth tuning to the desired channel without causing unnecessary charge pump action, it is recommended to consider the difference between wanted channel frequency and the current channel frequency. Unnecessary charge pump action will result in very low tuning voltage which may drive the oscillator to extreme conditions”. Set cb_first_if_lower_freq to 1, if this check is required for this tuner. I tested this for PAL by first setting the TV frequency to 203 MHz and then switching to 96.6 MHz FM radio. The result was static unless the control byte was sent first.

has_tda9887

  Set to 1 if this tuner uses a tda9887

port1_fm_high_sensitivity

  Many Philips tuners use tda9887 PORT1 to select the FM radio sensitivity. If this setting is 1, then set PORT1 to 1 to get proper FM reception.

port2_fm_high_sensitivity

  Some Philips tuners use tda9887 PORT2 to select the FM radio sensitivity. If this setting is 1, then set PORT2 to 1 to get proper FM reception.

fm_gain_normal

  Some Philips tuners use tda9887 cGainNormal to select the FM radio sensitivity. If this setting is 1, e register will use cGainNormal instead of cGainLow.

intercarrier_mode

  Most tuners with a tda9887 use QSS mode. Some (cheaper) tuners use Intercarrier mode. If this setting is 1, then the tuner needs to be set to intercarrier mode.

port1_active

  This setting sets the default value for PORT1. 0 means inactive, 1 means active. Note: the actual bit value written to the tda9887 is inverted. So a 0 here means a 1 in the B6 bit.

port2_active

  This setting sets the default value for PORT2. 0 means inactive, 1 means active. Note: the actual bit value written to the tda9887 is inverted. So a 0 here means a 1 in the B7 bit.

port1_invert_for_secam_lc

  Sometimes PORT1 is inverted when the SECAM-L' standard is selected. Set this bit to 1 if this is needed.

port2_invert_for_secam_lc

  Sometimes PORT2 is inverted when the SECAM-L' standard is selected. Set this bit to 1 if this is needed.

port1_set_for_fm_mono

  Some cards require PORT1 to be 1 for mono Radio FM and 0 for stereo.

default_pll_gating_18

  Select 18% (or according to datasheet 0%) L standard PLL gating, vs the driver default of 36%.

radio_if

  IF to use in radio mode. Tuners with a separate radio IF filter seem to use 10.7, while those without use 33.3 for PAL/SECAM tuners and 41.3 for NTSC tuners. 0 = 10.7, 1 = 33.3, 2 = 41.3

default_top_low

  Default tda9887 TOP value in dB for the low band. Default is 0. Range: -16:+15

default_top_mid

  Default tda9887 TOP value in dB for the mid band. Default is 0. Range: -16:+15

default_top_high

  Default tda9887 TOP value in dB for the high band. Default is 0. Range: -16:+15

default_top_secam_low

  Default tda9887 TOP value in dB for SECAM-L/L' for the low band. Default is 0. Several tuners require a different TOP value for the SECAM-L/L' standards. Range: -16:+15

default_top_secam_mid

  Default tda9887 TOP value in dB for SECAM-L/L' for the mid band. Default is 0. Several tuners require a different TOP value for the SECAM-L/L' standards. Range: -16:+15

default_top_secam_high

  Default tda9887 TOP value in dB for SECAM-L/L' for the high band. Default is 0. Several tuners require a different TOP value for the SECAM-L/L' standards. Range: -16:+15

iffreq

  Intermediate frequency (IF) used by the tuner on digital mode.

count

  Size of the ranges array.

ranges

  Array with the frequency ranges supported by the tuner.

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