1 /* SPDX-License-Identifier: GPL-2.0 */ 1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_UNITS_H 2 #ifndef _LINUX_UNITS_H
3 #define _LINUX_UNITS_H 3 #define _LINUX_UNITS_H
4 4
5 #include <linux/bits.h> 5 #include <linux/bits.h>
6 #include <linux/math.h> 6 #include <linux/math.h>
7 7
8 /* Metric prefixes in accordance with Système 8 /* Metric prefixes in accordance with Système international (d'unités) */
9 #define PETA 1000000000000000ULL 9 #define PETA 1000000000000000ULL
10 #define TERA 1000000000000ULL 10 #define TERA 1000000000000ULL
11 #define GIGA 1000000000UL 11 #define GIGA 1000000000UL
12 #define MEGA 1000000UL 12 #define MEGA 1000000UL
13 #define KILO 1000UL 13 #define KILO 1000UL
14 #define HECTO 100UL 14 #define HECTO 100UL
15 #define DECA 10UL 15 #define DECA 10UL
16 #define DECI 10UL 16 #define DECI 10UL
17 #define CENTI 100UL 17 #define CENTI 100UL
18 #define MILLI 1000UL 18 #define MILLI 1000UL
19 #define MICRO 1000000UL 19 #define MICRO 1000000UL
20 #define NANO 1000000000UL 20 #define NANO 1000000000UL
21 #define PICO 1000000000000ULL 21 #define PICO 1000000000000ULL
22 #define FEMTO 1000000000000000ULL 22 #define FEMTO 1000000000000000ULL
23 23
24 #define NANOHZ_PER_HZ 1000000000UL 24 #define NANOHZ_PER_HZ 1000000000UL
25 #define MICROHZ_PER_HZ 1000000UL 25 #define MICROHZ_PER_HZ 1000000UL
26 #define MILLIHZ_PER_HZ 1000UL 26 #define MILLIHZ_PER_HZ 1000UL
27 27
28 #define HZ_PER_KHZ 1000UL 28 #define HZ_PER_KHZ 1000UL
29 #define HZ_PER_MHZ 1000000UL 29 #define HZ_PER_MHZ 1000000UL
30 30
31 #define KHZ_PER_MHZ 1000UL 31 #define KHZ_PER_MHZ 1000UL
32 #define KHZ_PER_GHZ 1000000UL 32 #define KHZ_PER_GHZ 1000000UL
33 33
34 #define MILLIWATT_PER_WATT 1000UL 34 #define MILLIWATT_PER_WATT 1000UL
35 #define MICROWATT_PER_MILLIWATT 1000UL 35 #define MICROWATT_PER_MILLIWATT 1000UL
36 #define MICROWATT_PER_WATT 1000000UL 36 #define MICROWATT_PER_WATT 1000000UL
37 37
38 #define BYTES_PER_KBIT (KILO / BITS_P 38 #define BYTES_PER_KBIT (KILO / BITS_PER_BYTE)
39 #define BYTES_PER_MBIT (MEGA / BITS_P 39 #define BYTES_PER_MBIT (MEGA / BITS_PER_BYTE)
40 #define BYTES_PER_GBIT (GIGA / BITS_P 40 #define BYTES_PER_GBIT (GIGA / BITS_PER_BYTE)
41 41
42 #define ABSOLUTE_ZERO_MILLICELSIUS -273150 42 #define ABSOLUTE_ZERO_MILLICELSIUS -273150
43 43
44 static inline long milli_kelvin_to_millicelsiu 44 static inline long milli_kelvin_to_millicelsius(long t)
45 { 45 {
46 return t + ABSOLUTE_ZERO_MILLICELSIUS; 46 return t + ABSOLUTE_ZERO_MILLICELSIUS;
47 } 47 }
48 48
49 static inline long millicelsius_to_milli_kelvi 49 static inline long millicelsius_to_milli_kelvin(long t)
50 { 50 {
51 return t - ABSOLUTE_ZERO_MILLICELSIUS; 51 return t - ABSOLUTE_ZERO_MILLICELSIUS;
52 } 52 }
53 53
54 #define MILLIDEGREE_PER_DEGREE 1000 54 #define MILLIDEGREE_PER_DEGREE 1000
55 #define MILLIDEGREE_PER_DECIDEGREE 100 55 #define MILLIDEGREE_PER_DECIDEGREE 100
56 56
57 static inline long kelvin_to_millicelsius(long 57 static inline long kelvin_to_millicelsius(long t)
58 { 58 {
59 return milli_kelvin_to_millicelsius(t 59 return milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DEGREE);
60 } 60 }
61 61
62 static inline long millicelsius_to_kelvin(long 62 static inline long millicelsius_to_kelvin(long t)
63 { 63 {
64 t = millicelsius_to_milli_kelvin(t); 64 t = millicelsius_to_milli_kelvin(t);
65 65
66 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 66 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DEGREE);
67 } 67 }
68 68
69 static inline long deci_kelvin_to_celsius(long 69 static inline long deci_kelvin_to_celsius(long t)
70 { 70 {
71 t = milli_kelvin_to_millicelsius(t * M 71 t = milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DECIDEGREE);
72 72
73 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 73 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DEGREE);
74 } 74 }
75 75
76 static inline long celsius_to_deci_kelvin(long 76 static inline long celsius_to_deci_kelvin(long t)
77 { 77 {
78 t = millicelsius_to_milli_kelvin(t * M 78 t = millicelsius_to_milli_kelvin(t * MILLIDEGREE_PER_DEGREE);
79 79
80 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 80 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DECIDEGREE);
81 } 81 }
82 82
83 /** 83 /**
84 * deci_kelvin_to_millicelsius_with_offset - c 84 * deci_kelvin_to_millicelsius_with_offset - convert Kelvin to Celsius
85 * @t: temperature value in decidegrees Kelvin 85 * @t: temperature value in decidegrees Kelvin
86 * @offset: difference between Kelvin and Cels 86 * @offset: difference between Kelvin and Celsius in millidegrees
87 * 87 *
88 * Return: temperature value in millidegrees C 88 * Return: temperature value in millidegrees Celsius
89 */ 89 */
90 static inline long deci_kelvin_to_millicelsius 90 static inline long deci_kelvin_to_millicelsius_with_offset(long t, long offset)
91 { 91 {
92 return t * MILLIDEGREE_PER_DECIDEGREE 92 return t * MILLIDEGREE_PER_DECIDEGREE - offset;
93 } 93 }
94 94
95 static inline long deci_kelvin_to_millicelsius 95 static inline long deci_kelvin_to_millicelsius(long t)
96 { 96 {
97 return milli_kelvin_to_millicelsius(t 97 return milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DECIDEGREE);
98 } 98 }
99 99
100 static inline long millicelsius_to_deci_kelvin 100 static inline long millicelsius_to_deci_kelvin(long t)
101 { 101 {
102 t = millicelsius_to_milli_kelvin(t); 102 t = millicelsius_to_milli_kelvin(t);
103 103
104 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 104 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DECIDEGREE);
105 } 105 }
106 106
107 static inline long kelvin_to_celsius(long t) 107 static inline long kelvin_to_celsius(long t)
108 { 108 {
109 return t + DIV_ROUND_CLOSEST(ABSOLUTE_ 109 return t + DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS,
110 MILLIDEGR 110 MILLIDEGREE_PER_DEGREE);
111 } 111 }
112 112
113 static inline long celsius_to_kelvin(long t) 113 static inline long celsius_to_kelvin(long t)
114 { 114 {
115 return t - DIV_ROUND_CLOSEST(ABSOLUTE_ 115 return t - DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS,
116 MILLIDEGR 116 MILLIDEGREE_PER_DEGREE);
117 } 117 }
118 118
119 #endif /* _LINUX_UNITS_H */ 119 #endif /* _LINUX_UNITS_H */
120 120
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