include/linux/map_to_7segment.h

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