include/linux/linear_range.h

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright (C) 2020 ROHM Semiconductors */

#ifndef LINEAR_RANGE_H
#define LINEAR_RANGE_H

#include <linux/types.h>

/**
 * struct linear_range - table of selector - value pairs
 *
 * Define a lookup-table for range of values. Intended to help when looking
 * for a register value matching certaing physical measure (like voltage).
 * Usable when increment of one in register always results a constant increment
 * of the physical measure (like voltage).
 *
 * @min:  Lowest value in range
 * @min_sel: Lowest selector for range
 * @max_sel: Highest selector for range
 * @step: Value step size
 */
struct linear_range {
	unsigned int min;
	unsigned int min_sel;
	unsigned int max_sel;
	unsigned int step;
};

#define LINEAR_RANGE(_min, _min_sel, _max_sel, _step)		\
	{							\
		.min = _min,					\
		.min_sel = _min_sel,				\
		.max_sel = _max_sel,				\
		.step = _step,					\
	}

#define LINEAR_RANGE_IDX(_idx, _min, _min_sel, _max_sel, _step)	\
	[_idx] = LINEAR_RANGE(_min, _min_sel, _max_sel, _step)

unsigned int linear_range_values_in_range(const struct linear_range *r);
unsigned int linear_range_values_in_range_array(const struct linear_range *r,
						int ranges);
unsigned int linear_range_get_max_value(const struct linear_range *r);

int linear_range_get_value(const struct linear_range *r, unsigned int selector,
			   unsigned int *val);
int linear_range_get_value_array(const struct linear_range *r, int ranges,
				 unsigned int selector, unsigned int *val);
int linear_range_get_selector_low(const struct linear_range *r,
				  unsigned int val, unsigned int *selector,
				  bool *found);
int linear_range_get_selector_high(const struct linear_range *r,
				   unsigned int val, unsigned int *selector,
				   bool *found);
void linear_range_get_selector_within(const struct linear_range *r,
				      unsigned int val, unsigned int *selector);
int linear_range_get_selector_low_array(const struct linear_range *r,
					int ranges, unsigned int val,
					unsigned int *selector, bool *found);

#endif