include/linux/spi/ads7846.h

   1 /* linux/spi/ads7846.h */
   2
   3 /* Touchscreen characteristics vary between boards and models.  The
   4  * platform_data for the device's "struct device" holds this information.
   5  *
   6  * It's OK if the min/max values are zero.
   7  */
   8 enum ads7846_filter {
   9         ADS7846_FILTER_OK,
  10         ADS7846_FILTER_REPEAT,
  11         ADS7846_FILTER_IGNORE,
  12 };
  13
  14 struct ads7846_platform_data {
  15         u16     model;                  /* 7843, 7845, 7846. */
  16         u16     vref_delay_usecs;       /* 0 for external vref; etc */
  17         int     keep_vref_on:1;         /* set to keep vref on for differential
  18                                          * measurements as well */
  19         u16     x_plate_ohms;
  20         u16     y_plate_ohms;
  21
  22         u16     x_min, x_max;
  23         u16     y_min, y_max;
  24         u16     pressure_min, pressure_max;
  25
  26         u16     debounce_max;           /* max number of additional readings
  27                                          * per sample */
  28         u16     debounce_tol;           /* tolerance used for filtering */
  29         u16     debounce_rep;           /* additional consecutive good readings
  30                                          * required after the first two */
  31         int     (*get_pendown_state)(void);
  32         int     (*filter_init)  (struct ads7846_platform_data *pdata,
  33                                  void **filter_data);
  34         int     (*filter)       (void *filter_data, int data_idx, int *val);
  35         void    (*filter_cleanup)(void *filter_data);
  36 };
  37