From e12ef7bf34113f55c9bf444a680a15b6daf76f26 Mon Sep 17 00:00:00 2001 From: Gene Chen Date: Mon, 19 Jul 2021 11:39:12 +0800 Subject: [PATCH] lib: add linear range get selector within Add linear range get selector within for choose closest selector between minimum and maximum selector. Signed-off-by: Gene Chen Reviewed-by: Matti Vaittinen Signed-off-by: Sebastian Reichel --- include/linux/linear_range.h | 2 ++ lib/linear_ranges.c | 31 +++++++++++++++++++++++++++++++ 2 files changed, 33 insertions(+) diff --git a/include/linux/linear_range.h b/include/linux/linear_range.h index 17b5943727d5..fd3d0b358f22 100644 --- a/include/linux/linear_range.h +++ b/include/linux/linear_range.h @@ -41,6 +41,8 @@ int linear_range_get_selector_low(const struct linear_range *r, 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); diff --git a/lib/linear_ranges.c b/lib/linear_ranges.c index ced5c15d3f04..a1a7dfa881de 100644 --- a/lib/linear_ranges.c +++ b/lib/linear_ranges.c @@ -241,5 +241,36 @@ int linear_range_get_selector_high(const struct linear_range *r, } EXPORT_SYMBOL_GPL(linear_range_get_selector_high); +/** + * linear_range_get_selector_within - return linear range selector for value + * @r: pointer to linear range where selector is looked from + * @val: value for which the selector is searched + * @selector: address where found selector value is updated + * + * Return selector for which range value is closest match for given + * input value. Value is matching if it is equal or lower than given + * value. But return maximum selector if given value is higher than + * maximum value. + */ +void linear_range_get_selector_within(const struct linear_range *r, + unsigned int val, unsigned int *selector) +{ + if (r->min > val) { + *selector = r->min_sel; + return; + } + + if (linear_range_get_max_value(r) < val) { + *selector = r->max_sel; + return; + } + + if (r->step == 0) + *selector = r->min_sel; + else + *selector = (val - r->min) / r->step + r->min_sel; +} +EXPORT_SYMBOL_GPL(linear_range_get_selector_within); + MODULE_DESCRIPTION("linear-ranges helper"); MODULE_LICENSE("GPL");