include/linux/linear_range.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /* Copyright (C) 2020 ROHM Semiconductors */
   3
   4 #ifndef LINEAR_RANGE_H
   5 #define LINEAR_RANGE_H
   6
   7 #include <linux/types.h>
   8
   9 /**
  10  * struct linear_range - table of selector - value pairs
  11  *
  12  * Define a lookup-table for range of values. Intended to help when looking
  13  * for a register value matching certaing physical measure (like voltage).
  14  * Usable when increment of one in register always results a constant increment
  15  * of the physical measure (like voltage).
  16  *
  17  * @min:  Lowest value in range
  18  * @min_sel: Lowest selector for range
  19  * @max_sel: Highest selector for range
  20  * @step: Value step size
  21  */
  22 struct linear_range {
  23         unsigned int min;
  24         unsigned int min_sel;
  25         unsigned int max_sel;
  26         unsigned int step;
  27 };
  28
  29 #define LINEAR_RANGE(_min, _min_sel, _max_sel, _step)           \
  30         {                                                       \
  31                 .min = _min,                                    \
  32                 .min_sel = _min_sel,                            \
  33                 .max_sel = _max_sel,                            \
  34                 .step = _step,                                  \
  35         }
  36
  37 #define LINEAR_RANGE_IDX(_idx, _min, _min_sel, _max_sel, _step) \
  38         [_idx] = LINEAR_RANGE(_min, _min_sel, _max_sel, _step)
  39
  40 unsigned int linear_range_values_in_range(const struct linear_range *r);
  41 unsigned int linear_range_values_in_range_array(const struct linear_range *r,
  42                                                 int ranges);
  43 unsigned int linear_range_get_max_value(const struct linear_range *r);
  44
  45 int linear_range_get_value(const struct linear_range *r, unsigned int selector,
  46                            unsigned int *val);
  47 int linear_range_get_value_array(const struct linear_range *r, int ranges,
  48                                  unsigned int selector, unsigned int *val);
  49 int linear_range_get_selector_low(const struct linear_range *r,
  50                                   unsigned int val, unsigned int *selector,
  51                                   bool *found);
  52 int linear_range_get_selector_high(const struct linear_range *r,
  53                                    unsigned int val, unsigned int *selector,
  54                                    bool *found);
  55 void linear_range_get_selector_within(const struct linear_range *r,
  56                                       unsigned int val, unsigned int *selector);
  57 int linear_range_get_selector_low_array(const struct linear_range *r,
  58                                         int ranges, unsigned int val,
  59                                         unsigned int *selector, bool *found);
  60
  61 #endif