include/media/tuner-types.h

   1 /*
   2  * descriptions for simple tuners.
   3  */
   4
   5 #ifndef __TUNER_TYPES_H__
   6 #define __TUNER_TYPES_H__
   7
   8 enum param_type {
   9         TUNER_PARAM_TYPE_RADIO, \
  10         TUNER_PARAM_TYPE_PAL, \
  11         TUNER_PARAM_TYPE_SECAM, \
  12         TUNER_PARAM_TYPE_NTSC
  13 };
  14
  15 struct tuner_range {
  16         unsigned short limit;
  17         unsigned char config;
  18         unsigned char cb;
  19 };
  20
  21 struct tuner_params {
  22         enum param_type type;
  23         /* Many Philips based tuners have a comment like this in their
  24          * datasheet:
  25          *
  26          *   For channel selection involving band switching, and to ensure
  27          *   smooth tuning to the desired channel without causing
  28          *   unnecessary charge pump action, it is recommended to consider
  29          *   the difference between wanted channel frequency and the
  30          *   current channel frequency.  Unnecessary charge pump action
  31          *   will result in very low tuning voltage which may drive the
  32          *   oscillator to extreme conditions.
  33          *
  34          * Set cb_first_if_lower_freq to 1, if this check is
  35          * required for this tuner.
  36          *
  37          * I tested this for PAL by first setting the TV frequency to
  38          * 203 MHz and then switching to 96.6 MHz FM radio. The result was
  39          * static unless the control byte was sent first.
  40          */
  41         unsigned int cb_first_if_lower_freq:1;
  42
  43         unsigned int count;
  44         struct tuner_range *ranges;
  45 };
  46
  47 struct tunertype {
  48         char *name;
  49         unsigned int count;
  50         struct tuner_params *params;
  51 };
  52
  53 extern struct tunertype tuners[];
  54 extern unsigned const int tuner_count;
  55
  56 #endif