Input: ads7846 - pluggable filtering logic
[profile/ivi/kernel-x86-ivi.git] / 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         u16     x_plate_ohms;
18         u16     y_plate_ohms;
19
20         u16     x_min, x_max;
21         u16     y_min, y_max;
22         u16     pressure_min, pressure_max;
23
24         u16     debounce_max;           /* max number of additional readings
25                                          * per sample */
26         u16     debounce_tol;           /* tolerance used for filtering */
27         u16     debounce_rep;           /* additional consecutive good readings
28                                          * required after the first two */
29         int     (*get_pendown_state)(void);
30         int     (*filter_init)  (struct ads7846_platform_data *pdata,
31                                  void **filter_data);
32         int     (*filter)       (void *filter_data, int data_idx, int *val);
33         void    (*filter_cleanup)(void *filter_data);
34 };
35