18c2ecf20Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0
28c2ecf20Sopenharmony_ci/*
38c2ecf20Sopenharmony_ci * An integer based power function
48c2ecf20Sopenharmony_ci *
58c2ecf20Sopenharmony_ci * Derived from drivers/video/backlight/pwm_bl.c
68c2ecf20Sopenharmony_ci */
78c2ecf20Sopenharmony_ci
88c2ecf20Sopenharmony_ci#include <linux/export.h>
98c2ecf20Sopenharmony_ci#include <linux/kernel.h>
108c2ecf20Sopenharmony_ci#include <linux/types.h>
118c2ecf20Sopenharmony_ci
128c2ecf20Sopenharmony_ci/**
138c2ecf20Sopenharmony_ci * int_pow - computes the exponentiation of the given base and exponent
148c2ecf20Sopenharmony_ci * @base: base which will be raised to the given power
158c2ecf20Sopenharmony_ci * @exp: power to be raised to
168c2ecf20Sopenharmony_ci *
178c2ecf20Sopenharmony_ci * Computes: pow(base, exp), i.e. @base raised to the @exp power
188c2ecf20Sopenharmony_ci */
198c2ecf20Sopenharmony_ciu64 int_pow(u64 base, unsigned int exp)
208c2ecf20Sopenharmony_ci{
218c2ecf20Sopenharmony_ci	u64 result = 1;
228c2ecf20Sopenharmony_ci
238c2ecf20Sopenharmony_ci	while (exp) {
248c2ecf20Sopenharmony_ci		if (exp & 1)
258c2ecf20Sopenharmony_ci			result *= base;
268c2ecf20Sopenharmony_ci		exp >>= 1;
278c2ecf20Sopenharmony_ci		base *= base;
288c2ecf20Sopenharmony_ci	}
298c2ecf20Sopenharmony_ci
308c2ecf20Sopenharmony_ci	return result;
318c2ecf20Sopenharmony_ci}
328c2ecf20Sopenharmony_ciEXPORT_SYMBOL_GPL(int_pow);
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