1/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2/*
3 * Copyright (c) 2005 Henk Vergonet <Henk.Vergonet@gmail.com>
4 */
5
6#ifndef MAP_TO_7SEGMENT_H
7#define MAP_TO_7SEGMENT_H
8
9/* This file provides translation primitives and tables for the conversion
10 * of (ASCII) characters to a 7-segments notation.
11 *
12 * The 7 segment's wikipedia notation below is used as standard.
13 * See: https://en.wikipedia.org/wiki/Seven_segment_display
14 *
15 * Notation: +-a-+
16 * f b
17 * +-g-+
18 * e c
19 * +-d-+
20 *
21 * Usage:
22 *
23 * Register a map variable, and fill it with a character set:
24 * static SEG7_DEFAULT_MAP(map_seg7);
25 *
26 *
27 * Then use for conversion:
28 * seg7 = map_to_seg7(&map_seg7, some_char);
29 * ...
30 *
31 * In device drivers it is recommended, if required, to make the char map
32 * accessible via the sysfs interface using the following scheme:
33 *
34 * static ssize_t map_seg7_show(struct device *dev,
35 * struct device_attribute *attr, char *buf)
36 * {
37 * memcpy(buf, &map_seg7, sizeof(map_seg7));
38 * return sizeof(map_seg7);
39 * }
40 * static ssize_t map_seg7_store(struct device *dev,
41 * struct device_attribute *attr, const char *buf,
42 * size_t cnt)
43 * {
44 * if(cnt != sizeof(map_seg7))
45 * return -EINVAL;
46 * memcpy(&map_seg7, buf, cnt);
47 * return cnt;
48 * }
49 * static DEVICE_ATTR_RW(map_seg7);
50 *
51 * History:
52 * 2005-05-31 RFC linux-kernel@vger.kernel.org
53 */
54#include <linux/errno.h>
55
56
57#define BIT_SEG7_A 0
58#define BIT_SEG7_B 1
59#define BIT_SEG7_C 2
60#define BIT_SEG7_D 3
61#define BIT_SEG7_E 4
62#define BIT_SEG7_F 5
63#define BIT_SEG7_G 6
64#define BIT_SEG7_RESERVED 7
65
66struct seg7_conversion_map {
67 unsigned char table[128];
68};
69
70static __inline__ int map_to_seg7(struct seg7_conversion_map *map, int c)
71{
72 return c >= 0 && c < sizeof(map->table) ? map->table[c] : -EINVAL;
73}
74
75#define SEG7_CONVERSION_MAP(_name, _map) \
76 struct seg7_conversion_map _name = { .table = { _map } }
77
78/*
79 * It is recommended to use a facility that allows user space to redefine
80 * custom character sets for LCD devices. Please use a sysfs interface
81 * as described above.
82 */
83#define MAP_TO_SEG7_SYSFS_FILE "map_seg7"
84
85/*******************************************************************************
86 * ASCII conversion table
87 ******************************************************************************/
88
89#define _SEG7(l,a,b,c,d,e,f,g) \
90 ( a<<BIT_SEG7_A | b<<BIT_SEG7_B | c<<BIT_SEG7_C | d<<BIT_SEG7_D | \
91 e<<BIT_SEG7_E | f<<BIT_SEG7_F | g<<BIT_SEG7_G )
92
93#define _MAP_0_32_ASCII_SEG7_NON_PRINTABLE \
94 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
95
96#define _MAP_33_47_ASCII_SEG7_SYMBOL \
97 _SEG7('!',0,0,0,0,1,1,0), _SEG7('"',0,1,0,0,0,1,0), _SEG7('#',0,1,1,0,1,1,0),\
98 _SEG7('$',1,0,1,1,0,1,1), _SEG7('%',0,0,1,0,0,1,0), _SEG7('&',1,0,1,1,1,1,1),\
99 _SEG7('\'',0,0,0,0,0,1,0),_SEG7('(',1,0,0,1,1,1,0), _SEG7(')',1,1,1,1,0,0,0),\
100 _SEG7('*',0,1,1,0,1,1,1), _SEG7('+',0,1,1,0,0,0,1), _SEG7(',',0,0,0,0,1,0,0),\
101 _SEG7('-',0,0,0,0,0,0,1), _SEG7('.',0,0,0,0,1,0,0), _SEG7('/',0,1,0,0,1,0,1),
102
103#define _MAP_48_57_ASCII_SEG7_NUMERIC \
104 _SEG7('0',1,1,1,1,1,1,0), _SEG7('1',0,1,1,0,0,0,0), _SEG7('2',1,1,0,1,1,0,1),\
105 _SEG7('3',1,1,1,1,0,0,1), _SEG7('4',0,1,1,0,0,1,1), _SEG7('5',1,0,1,1,0,1,1),\
106 _SEG7('6',1,0,1,1,1,1,1), _SEG7('7',1,1,1,0,0,0,0), _SEG7('8',1,1,1,1,1,1,1),\
107 _SEG7('9',1,1,1,1,0,1,1),
108
109#define _MAP_58_64_ASCII_SEG7_SYMBOL \
110 _SEG7(':',0,0,0,1,0,0,1), _SEG7(';',0,0,0,1,0,0,1), _SEG7('<',1,0,0,0,0,1,1),\
111 _SEG7('=',0,0,0,1,0,0,1), _SEG7('>',1,1,0,0,0,0,1), _SEG7('?',1,1,1,0,0,1,0),\
112 _SEG7('@',1,1,0,1,1,1,1),
113
114#define _MAP_65_90_ASCII_SEG7_ALPHA_UPPR \
115 _SEG7('A',1,1,1,0,1,1,1), _SEG7('B',1,1,1,1,1,1,1), _SEG7('C',1,0,0,1,1,1,0),\
116 _SEG7('D',1,1,1,1,1,1,0), _SEG7('E',1,0,0,1,1,1,1), _SEG7('F',1,0,0,0,1,1,1),\
117 _SEG7('G',1,1,1,1,0,1,1), _SEG7('H',0,1,1,0,1,1,1), _SEG7('I',0,1,1,0,0,0,0),\
118 _SEG7('J',0,1,1,1,0,0,0), _SEG7('K',0,1,1,0,1,1,1), _SEG7('L',0,0,0,1,1,1,0),\
119 _SEG7('M',1,1,1,0,1,1,0), _SEG7('N',1,1,1,0,1,1,0), _SEG7('O',1,1,1,1,1,1,0),\
120 _SEG7('P',1,1,0,0,1,1,1), _SEG7('Q',1,1,1,1,1,1,0), _SEG7('R',1,1,1,0,1,1,1),\
121 _SEG7('S',1,0,1,1,0,1,1), _SEG7('T',0,0,0,1,1,1,1), _SEG7('U',0,1,1,1,1,1,0),\
122 _SEG7('V',0,1,1,1,1,1,0), _SEG7('W',0,1,1,1,1,1,1), _SEG7('X',0,1,1,0,1,1,1),\
123 _SEG7('Y',0,1,1,0,0,1,1), _SEG7('Z',1,1,0,1,1,0,1),
124
125#define _MAP_91_96_ASCII_SEG7_SYMBOL \
126 _SEG7('[',1,0,0,1,1,1,0), _SEG7('\\',0,0,1,0,0,1,1),_SEG7(']',1,1,1,1,0,0,0),\
127 _SEG7('^',1,1,0,0,0,1,0), _SEG7('_',0,0,0,1,0,0,0), _SEG7('`',0,1,0,0,0,0,0),
128
129#define _MAP_97_122_ASCII_SEG7_ALPHA_LOWER \
130 _SEG7('A',1,1,1,0,1,1,1), _SEG7('b',0,0,1,1,1,1,1), _SEG7('c',0,0,0,1,1,0,1),\
131 _SEG7('d',0,1,1,1,1,0,1), _SEG7('E',1,0,0,1,1,1,1), _SEG7('F',1,0,0,0,1,1,1),\
132 _SEG7('G',1,1,1,1,0,1,1), _SEG7('h',0,0,1,0,1,1,1), _SEG7('i',0,0,1,0,0,0,0),\
133 _SEG7('j',0,0,1,1,0,0,0), _SEG7('k',0,0,1,0,1,1,1), _SEG7('L',0,0,0,1,1,1,0),\
134 _SEG7('M',1,1,1,0,1,1,0), _SEG7('n',0,0,1,0,1,0,1), _SEG7('o',0,0,1,1,1,0,1),\
135 _SEG7('P',1,1,0,0,1,1,1), _SEG7('q',1,1,1,0,0,1,1), _SEG7('r',0,0,0,0,1,0,1),\
136 _SEG7('S',1,0,1,1,0,1,1), _SEG7('T',0,0,0,1,1,1,1), _SEG7('u',0,0,1,1,1,0,0),\
137 _SEG7('v',0,0,1,1,1,0,0), _SEG7('W',0,1,1,1,1,1,1), _SEG7('X',0,1,1,0,1,1,1),\
138 _SEG7('y',0,1,1,1,0,1,1), _SEG7('Z',1,1,0,1,1,0,1),
139
140#define _MAP_123_126_ASCII_SEG7_SYMBOL \
141 _SEG7('{',1,0,0,1,1,1,0), _SEG7('|',0,0,0,0,1,1,0), _SEG7('}',1,1,1,1,0,0,0),\
142 _SEG7('~',1,0,0,0,0,0,0),
143
144/* Maps */
145
146/* This set tries to map as close as possible to the visible characteristics
147 * of the ASCII symbol, lowercase and uppercase letters may differ in
148 * presentation on the display.
149 */
150#define MAP_ASCII7SEG_ALPHANUM \
151 _MAP_0_32_ASCII_SEG7_NON_PRINTABLE \
152 _MAP_33_47_ASCII_SEG7_SYMBOL \
153 _MAP_48_57_ASCII_SEG7_NUMERIC \
154 _MAP_58_64_ASCII_SEG7_SYMBOL \
155 _MAP_65_90_ASCII_SEG7_ALPHA_UPPR \
156 _MAP_91_96_ASCII_SEG7_SYMBOL \
157 _MAP_97_122_ASCII_SEG7_ALPHA_LOWER \
158 _MAP_123_126_ASCII_SEG7_SYMBOL
159
160/* This set tries to map as close as possible to the symbolic characteristics
161 * of the ASCII character for maximum discrimination.
162 * For now this means all alpha chars are in lower case representations.
163 * (This for example facilitates the use of hex numbers with uppercase input.)
164 */
165#define MAP_ASCII7SEG_ALPHANUM_LC \
166 _MAP_0_32_ASCII_SEG7_NON_PRINTABLE \
167 _MAP_33_47_ASCII_SEG7_SYMBOL \
168 _MAP_48_57_ASCII_SEG7_NUMERIC \
169 _MAP_58_64_ASCII_SEG7_SYMBOL \
170 _MAP_97_122_ASCII_SEG7_ALPHA_LOWER \
171 _MAP_91_96_ASCII_SEG7_SYMBOL \
172 _MAP_97_122_ASCII_SEG7_ALPHA_LOWER \
173 _MAP_123_126_ASCII_SEG7_SYMBOL
174
175#define SEG7_DEFAULT_MAP(_name) \
176 SEG7_CONVERSION_MAP(_name,MAP_ASCII7SEG_ALPHANUM)
177
178#endif /* MAP_TO_7SEGMENT_H */
179
180

source code of linux/include/uapi/linux/map_to_7segment.h