1 /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
2 /*
3  * Copyright (c) 2005 Henk Vergonet <Henk.Vergonet@gmail.com>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation; either version 2 of
8  * the License, or (at your option) any later version.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
18  */
19 
20 #ifndef MAP_TO_7SEGMENT_H
21 #define MAP_TO_7SEGMENT_H
22 
23 /* This file provides translation primitives and tables for the conversion
24  * of (ASCII) characters to a 7-segments notation.
25  *
26  * The 7 segment's wikipedia notation below is used as standard.
27  * See: http://en.wikipedia.org/wiki/Seven_segment_display
28  *
29  * Notation:	+-a-+
30  *		f   b
31  *		+-g-+
32  *		e   c
33  *		+-d-+
34  *
35  * Usage:
36  *
37  *   Register a map variable, and fill it with a character set:
38  *	static SEG7_DEFAULT_MAP(map_seg7);
39  *
40  *
41  *   Then use for conversion:
42  *	seg7 = map_to_seg7(&map_seg7, some_char);
43  *	...
44  *
45  * In device drivers it is recommended, if required, to make the char map
46  * accessible via the sysfs interface using the following scheme:
47  *
48  * static ssize_t show_map(struct device *dev, char *buf) {
49  *	memcpy(buf, &map_seg7, sizeof(map_seg7));
50  *	return sizeof(map_seg7);
51  * }
52  * static ssize_t store_map(struct device *dev, const char *buf, size_t cnt) {
53  *	if(cnt != sizeof(map_seg7))
54  *		return -EINVAL;
55  *	memcpy(&map_seg7, buf, cnt);
56  *	return cnt;
57  * }
58  * static DEVICE_ATTR(map_seg7, PERMS_RW, show_map, store_map);
59  *
60  * History:
61  * 2005-05-31	RFC linux-kernel@vger.kernel.org
62  */
63 #include <linux/errno.h>
64 
65 
66 #define BIT_SEG7_A		0
67 #define BIT_SEG7_B		1
68 #define BIT_SEG7_C		2
69 #define BIT_SEG7_D		3
70 #define BIT_SEG7_E		4
71 #define BIT_SEG7_F		5
72 #define BIT_SEG7_G		6
73 #define BIT_SEG7_RESERVED	7
74 
75 struct seg7_conversion_map {
76 	unsigned char	table[128];
77 };
78 
map_to_seg7(struct seg7_conversion_map * map,int c)79 static __inline__ int map_to_seg7(struct seg7_conversion_map *map, int c)
80 {
81 	return c >= 0 && c < sizeof(map->table) ? map->table[c] : -EINVAL;
82 }
83 
84 #define SEG7_CONVERSION_MAP(_name, _map)	\
85 	struct seg7_conversion_map _name = { .table = { _map } }
86 
87 /*
88  * It is recommended to use a facility that allows user space to redefine
89  * custom character sets for LCD devices. Please use a sysfs interface
90  * as described above.
91  */
92 #define MAP_TO_SEG7_SYSFS_FILE	"map_seg7"
93 
94 /*******************************************************************************
95  * ASCII conversion table
96  ******************************************************************************/
97 
98 #define _SEG7(l,a,b,c,d,e,f,g)	\
99       (	a<<BIT_SEG7_A |	b<<BIT_SEG7_B |	c<<BIT_SEG7_C |	d<<BIT_SEG7_D |	\
100 	e<<BIT_SEG7_E |	f<<BIT_SEG7_F |	g<<BIT_SEG7_G )
101 
102 #define _MAP_0_32_ASCII_SEG7_NON_PRINTABLE	\
103 	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,
104 
105 #define _MAP_33_47_ASCII_SEG7_SYMBOL		\
106  _SEG7('!',0,0,0,0,1,1,0), _SEG7('"',0,1,0,0,0,1,0), _SEG7('#',0,1,1,0,1,1,0),\
107  _SEG7('$',1,0,1,1,0,1,1), _SEG7('%',0,0,1,0,0,1,0), _SEG7('&',1,0,1,1,1,1,1),\
108  _SEG7('\'',0,0,0,0,0,1,0),_SEG7('(',1,0,0,1,1,1,0), _SEG7(')',1,1,1,1,0,0,0),\
109  _SEG7('*',0,1,1,0,1,1,1), _SEG7('+',0,1,1,0,0,0,1), _SEG7(',',0,0,0,0,1,0,0),\
110  _SEG7('-',0,0,0,0,0,0,1), _SEG7('.',0,0,0,0,1,0,0), _SEG7('/',0,1,0,0,1,0,1),
111 
112 #define _MAP_48_57_ASCII_SEG7_NUMERIC		\
113  _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),\
114  _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),\
115  _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),\
116  _SEG7('9',1,1,1,1,0,1,1),
117 
118 #define _MAP_58_64_ASCII_SEG7_SYMBOL		\
119  _SEG7(':',0,0,0,1,0,0,1), _SEG7(';',0,0,0,1,0,0,1), _SEG7('<',1,0,0,0,0,1,1),\
120  _SEG7('=',0,0,0,1,0,0,1), _SEG7('>',1,1,0,0,0,0,1), _SEG7('?',1,1,1,0,0,1,0),\
121  _SEG7('@',1,1,0,1,1,1,1),
122 
123 #define _MAP_65_90_ASCII_SEG7_ALPHA_UPPR	\
124  _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),\
125  _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),\
126  _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),\
127  _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),\
128  _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),\
129  _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),\
130  _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),\
131  _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),\
132  _SEG7('Y',0,1,1,0,0,1,1), _SEG7('Z',1,1,0,1,1,0,1),
133 
134 #define _MAP_91_96_ASCII_SEG7_SYMBOL		\
135  _SEG7('[',1,0,0,1,1,1,0), _SEG7('\\',0,0,1,0,0,1,1),_SEG7(']',1,1,1,1,0,0,0),\
136  _SEG7('^',1,1,0,0,0,1,0), _SEG7('_',0,0,0,1,0,0,0), _SEG7('`',0,1,0,0,0,0,0),
137 
138 #define _MAP_97_122_ASCII_SEG7_ALPHA_LOWER	\
139  _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),\
140  _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),\
141  _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),\
142  _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),\
143  _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),\
144  _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),\
145  _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),\
146  _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),\
147  _SEG7('y',0,1,1,1,0,1,1), _SEG7('Z',1,1,0,1,1,0,1),
148 
149 #define _MAP_123_126_ASCII_SEG7_SYMBOL		\
150  _SEG7('{',1,0,0,1,1,1,0), _SEG7('|',0,0,0,0,1,1,0), _SEG7('}',1,1,1,1,0,0,0),\
151  _SEG7('~',1,0,0,0,0,0,0),
152 
153 /* Maps */
154 
155 /* This set tries to map as close as possible to the visible characteristics
156  * of the ASCII symbol, lowercase and uppercase letters may differ in
157  * presentation on the display.
158  */
159 #define MAP_ASCII7SEG_ALPHANUM			\
160 	_MAP_0_32_ASCII_SEG7_NON_PRINTABLE	\
161 	_MAP_33_47_ASCII_SEG7_SYMBOL		\
162 	_MAP_48_57_ASCII_SEG7_NUMERIC		\
163 	_MAP_58_64_ASCII_SEG7_SYMBOL		\
164 	_MAP_65_90_ASCII_SEG7_ALPHA_UPPR	\
165 	_MAP_91_96_ASCII_SEG7_SYMBOL		\
166 	_MAP_97_122_ASCII_SEG7_ALPHA_LOWER	\
167 	_MAP_123_126_ASCII_SEG7_SYMBOL
168 
169 /* This set tries to map as close as possible to the symbolic characteristics
170  * of the ASCII character for maximum discrimination.
171  * For now this means all alpha chars are in lower case representations.
172  * (This for example facilitates the use of hex numbers with uppercase input.)
173  */
174 #define MAP_ASCII7SEG_ALPHANUM_LC			\
175 	_MAP_0_32_ASCII_SEG7_NON_PRINTABLE	\
176 	_MAP_33_47_ASCII_SEG7_SYMBOL		\
177 	_MAP_48_57_ASCII_SEG7_NUMERIC		\
178 	_MAP_58_64_ASCII_SEG7_SYMBOL		\
179 	_MAP_97_122_ASCII_SEG7_ALPHA_LOWER	\
180 	_MAP_91_96_ASCII_SEG7_SYMBOL		\
181 	_MAP_97_122_ASCII_SEG7_ALPHA_LOWER	\
182 	_MAP_123_126_ASCII_SEG7_SYMBOL
183 
184 #define SEG7_DEFAULT_MAP(_name)		\
185 	SEG7_CONVERSION_MAP(_name,MAP_ASCII7SEG_ALPHANUM)
186 
187 #endif	/* MAP_TO_7SEGMENT_H */
188 
189