projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 23331e48 AM |
1 | /* SPDX-License-Identifier: GPL-2.0 */ |
| 2 | #ifndef _LINUX_UNITS_H | |
| 3 | #define _LINUX_UNITS_H | |
| 4 | ||
| 5 | #include <linux/kernel.h> | |
| 6 | ||
| 7 | #define ABSOLUTE_ZERO_MILLICELSIUS -273150 | |
| 8 | ||
| 9 | static inline long milli_kelvin_to_millicelsius(long t) | |
| 10 | { | |
| 11 | return t + ABSOLUTE_ZERO_MILLICELSIUS; | |
| 12 | } | |
| 13 | ||
| 14 | static inline long millicelsius_to_milli_kelvin(long t) | |
| 15 | { | |
| 16 | return t - ABSOLUTE_ZERO_MILLICELSIUS; | |
| 17 | } | |
| 18 | ||
| 19 | #define MILLIDEGREE_PER_DEGREE 1000 | |
| 20 | #define MILLIDEGREE_PER_DECIDEGREE 100 | |
| 21 | ||
| 22 | static inline long kelvin_to_millicelsius(long t) | |
| 23 | { | |
| 24 | return milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DEGREE); | |
| 25 | } | |
| 26 | ||
| 27 | static inline long millicelsius_to_kelvin(long t) | |
| 28 | { | |
| 29 | t = millicelsius_to_milli_kelvin(t); | |
| 30 | ||
| 31 | return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DEGREE); | |
| 32 | } | |
| 33 | ||
| 34 | static inline long deci_kelvin_to_celsius(long t) | |
| 35 | { | |
| 36 | t = milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DECIDEGREE); | |
| 37 | ||
| 38 | return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DEGREE); | |
| 39 | } | |
| 40 | ||
| 41 | static inline long celsius_to_deci_kelvin(long t) | |
| 42 | { | |
| 43 | t = millicelsius_to_milli_kelvin(t * MILLIDEGREE_PER_DEGREE); | |
| 44 | ||
| 45 | return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DECIDEGREE); | |
| 46 | } | |
| 47 | ||
| 48 | /** | |
| 49 | * deci_kelvin_to_millicelsius_with_offset - convert Kelvin to Celsius | |
| 50 | * @t: temperature value in decidegrees Kelvin | |
| 51 | * @offset: difference between Kelvin and Celsius in millidegrees | |
| 52 | * | |
| 53 | * Return: temperature value in millidegrees Celsius | |
| 54 | */ | |
| 55 | static inline long deci_kelvin_to_millicelsius_with_offset(long t, long offset) | |
| 56 | { | |
| 57 | return t * MILLIDEGREE_PER_DECIDEGREE - offset; | |
| 58 | } | |
| 59 | ||
| 60 | static inline long deci_kelvin_to_millicelsius(long t) | |
| 61 | { | |
| 62 | return milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DECIDEGREE); | |
| 63 | } | |
| 64 | ||
| 65 | static inline long millicelsius_to_deci_kelvin(long t) | |
| 66 | { | |
| 67 | t = millicelsius_to_milli_kelvin(t); | |
| 68 | ||
| 69 | return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DECIDEGREE); | |
| 70 | } | |
| 71 | ||
| 72 | static inline long kelvin_to_celsius(long t) | |
| 73 | { | |
| 74 | return t + DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS, | |
| 75 | MILLIDEGREE_PER_DEGREE); | |
| 76 | } | |
| 77 | ||
| 78 | static inline long celsius_to_kelvin(long t) | |
| 79 | { | |
| 80 | return t - DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS, | |
| 81 | MILLIDEGREE_PER_DEGREE); | |
| 82 | } | |
| 83 | ||
| 84 | #endif /* _LINUX_UNITS_H */ |