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> <<
6 #include <linux/math.h> 5 #include <linux/math.h>
7 <<
8 /* Metric prefixes in accordance with Système <<
9 #define PETA 1000000000000000ULL <<
10 #define TERA 1000000000000ULL <<
11 #define GIGA 1000000000UL <<
12 #define MEGA 1000000UL <<
13 #define KILO 1000UL <<
14 #define HECTO 100UL <<
15 #define DECA 10UL <<
16 #define DECI 10UL <<
17 #define CENTI 100UL <<
18 #define MILLI 1000UL <<
19 #define MICRO 1000000UL <<
20 #define NANO 1000000000UL <<
21 #define PICO 1000000000000ULL <<
22 #define FEMTO 1000000000000000ULL <<
23 <<
24 #define NANOHZ_PER_HZ 1000000000UL <<
25 #define MICROHZ_PER_HZ 1000000UL <<
26 #define MILLIHZ_PER_HZ 1000UL <<
27 <<
28 #define HZ_PER_KHZ 1000UL <<
29 #define HZ_PER_MHZ 1000000UL <<
30 <<
31 #define KHZ_PER_MHZ 1000UL <<
32 #define KHZ_PER_GHZ 1000000UL <<
33 <<
34 #define MILLIWATT_PER_WATT 1000UL <<
35 #define MICROWATT_PER_MILLIWATT 1000UL <<
36 #define MICROWATT_PER_WATT 1000000UL <<
37 <<
38 #define BYTES_PER_KBIT (KILO / BITS_P <<
39 #define BYTES_PER_MBIT (MEGA / BITS_P <<
40 #define BYTES_PER_GBIT (GIGA / BITS_P <<
41 6
42 #define ABSOLUTE_ZERO_MILLICELSIUS -273150 7 #define ABSOLUTE_ZERO_MILLICELSIUS -273150
43 8
44 static inline long milli_kelvin_to_millicelsiu 9 static inline long milli_kelvin_to_millicelsius(long t)
45 { 10 {
46 return t + ABSOLUTE_ZERO_MILLICELSIUS; 11 return t + ABSOLUTE_ZERO_MILLICELSIUS;
47 } 12 }
48 13
49 static inline long millicelsius_to_milli_kelvi 14 static inline long millicelsius_to_milli_kelvin(long t)
50 { 15 {
51 return t - ABSOLUTE_ZERO_MILLICELSIUS; 16 return t - ABSOLUTE_ZERO_MILLICELSIUS;
52 } 17 }
53 18
54 #define MILLIDEGREE_PER_DEGREE 1000 19 #define MILLIDEGREE_PER_DEGREE 1000
55 #define MILLIDEGREE_PER_DECIDEGREE 100 20 #define MILLIDEGREE_PER_DECIDEGREE 100
56 21
57 static inline long kelvin_to_millicelsius(long 22 static inline long kelvin_to_millicelsius(long t)
58 { 23 {
59 return milli_kelvin_to_millicelsius(t 24 return milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DEGREE);
60 } 25 }
61 26
62 static inline long millicelsius_to_kelvin(long 27 static inline long millicelsius_to_kelvin(long t)
63 { 28 {
64 t = millicelsius_to_milli_kelvin(t); 29 t = millicelsius_to_milli_kelvin(t);
65 30
66 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 31 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DEGREE);
67 } 32 }
68 33
69 static inline long deci_kelvin_to_celsius(long 34 static inline long deci_kelvin_to_celsius(long t)
70 { 35 {
71 t = milli_kelvin_to_millicelsius(t * M 36 t = milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DECIDEGREE);
72 37
73 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 38 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DEGREE);
74 } 39 }
75 40
76 static inline long celsius_to_deci_kelvin(long 41 static inline long celsius_to_deci_kelvin(long t)
77 { 42 {
78 t = millicelsius_to_milli_kelvin(t * M 43 t = millicelsius_to_milli_kelvin(t * MILLIDEGREE_PER_DEGREE);
79 44
80 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 45 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DECIDEGREE);
81 } 46 }
82 47
83 /** 48 /**
84 * deci_kelvin_to_millicelsius_with_offset - c 49 * deci_kelvin_to_millicelsius_with_offset - convert Kelvin to Celsius
85 * @t: temperature value in decidegrees Kelvin 50 * @t: temperature value in decidegrees Kelvin
86 * @offset: difference between Kelvin and Cels 51 * @offset: difference between Kelvin and Celsius in millidegrees
87 * 52 *
88 * Return: temperature value in millidegrees C 53 * Return: temperature value in millidegrees Celsius
89 */ 54 */
90 static inline long deci_kelvin_to_millicelsius 55 static inline long deci_kelvin_to_millicelsius_with_offset(long t, long offset)
91 { 56 {
92 return t * MILLIDEGREE_PER_DECIDEGREE 57 return t * MILLIDEGREE_PER_DECIDEGREE - offset;
93 } 58 }
94 59
95 static inline long deci_kelvin_to_millicelsius 60 static inline long deci_kelvin_to_millicelsius(long t)
96 { 61 {
97 return milli_kelvin_to_millicelsius(t 62 return milli_kelvin_to_millicelsius(t * MILLIDEGREE_PER_DECIDEGREE);
98 } 63 }
99 64
100 static inline long millicelsius_to_deci_kelvin 65 static inline long millicelsius_to_deci_kelvin(long t)
101 { 66 {
102 t = millicelsius_to_milli_kelvin(t); 67 t = millicelsius_to_milli_kelvin(t);
103 68
104 return DIV_ROUND_CLOSEST(t, MILLIDEGRE 69 return DIV_ROUND_CLOSEST(t, MILLIDEGREE_PER_DECIDEGREE);
105 } 70 }
106 71
107 static inline long kelvin_to_celsius(long t) 72 static inline long kelvin_to_celsius(long t)
108 { 73 {
109 return t + DIV_ROUND_CLOSEST(ABSOLUTE_ 74 return t + DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS,
110 MILLIDEGR 75 MILLIDEGREE_PER_DEGREE);
111 } 76 }
112 77
113 static inline long celsius_to_kelvin(long t) 78 static inline long celsius_to_kelvin(long t)
114 { 79 {
115 return t - DIV_ROUND_CLOSEST(ABSOLUTE_ 80 return t - DIV_ROUND_CLOSEST(ABSOLUTE_ZERO_MILLICELSIUS,
116 MILLIDEGR 81 MILLIDEGREE_PER_DEGREE);
117 } 82 }
118 83
119 #endif /* _LINUX_UNITS_H */ 84 #endif /* _LINUX_UNITS_H */
120 85
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