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      1 /*
      2  * Copyright (c) 2005 Henk Vergonet <Henk.Vergonet (at) 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 (at) 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 
    188