9f61589469
The integer exponentiation is used in few places and might be used in the future by other call sites. Move it to wider use. Link: http://lkml.kernel.org/r/20190323172531.80025-2-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Lee Jones <lee.jones@linaro.org> Cc: Ray Jui <rjui@broadcom.com> Cc: Thierry Reding <thierry.reding@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
33 lines
631 B
C
33 lines
631 B
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* An integer based power function
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*
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* Derived from drivers/video/backlight/pwm_bl.c
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*/
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#include <linux/export.h>
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#include <linux/kernel.h>
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#include <linux/types.h>
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/**
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* int_pow - computes the exponentiation of the given base and exponent
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* @base: base which will be raised to the given power
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* @exp: power to be raised to
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*
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* Computes: pow(base, exp), i.e. @base raised to the @exp power
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*/
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u64 int_pow(u64 base, unsigned int exp)
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{
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u64 result = 1;
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while (exp) {
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if (exp & 1)
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result *= base;
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exp >>= 1;
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base *= base;
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}
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return result;
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}
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EXPORT_SYMBOL_GPL(int_pow);
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