drivers/auxdisplay/charlcd.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * Character LCD driver for Linux
   4  *
   5  * Copyright (C) 2000-2008, Willy Tarreau <w@1wt.eu>
   6  * Copyright (C) 2016-2017 Glider bvba
   7  */
   8
   9 #ifndef _CHARLCD_H
  10 #define _CHARLCD_H
  11
  12 #define LCD_FLAG_B              0x0004  /* Blink on */
  13 #define LCD_FLAG_C              0x0008  /* Cursor on */
  14 #define LCD_FLAG_D              0x0010  /* Display on */
  15 #define LCD_FLAG_F              0x0020  /* Large font mode */
  16 #define LCD_FLAG_N              0x0040  /* 2-rows mode */
  17 #define LCD_FLAG_L              0x0080  /* Backlight enabled */
  18
  19 enum charlcd_onoff {
  20         CHARLCD_OFF = 0,
  21         CHARLCD_ON,
  22 };
  23
  24 enum charlcd_shift_dir {
  25         CHARLCD_SHIFT_LEFT,
  26         CHARLCD_SHIFT_RIGHT,
  27 };
  28
  29 enum charlcd_fontsize {
  30         CHARLCD_FONTSIZE_SMALL,
  31         CHARLCD_FONTSIZE_LARGE,
  32 };
  33
  34 enum charlcd_lines {
  35         CHARLCD_LINES_1,
  36         CHARLCD_LINES_2,
  37 };
  38
  39 struct charlcd {
  40         const struct charlcd_ops *ops;
  41         const unsigned char *char_conv; /* Optional */
  42
  43         int height;
  44         int width;
  45
  46         /* Contains the LCD X and Y offset */
  47         struct {
  48                 unsigned long x;
  49                 unsigned long y;
  50         } addr;
  51
  52         void *drvdata;
  53 };
  54
  55 /**
  56  * struct charlcd_ops - Functions used by charlcd. Drivers have to implement
  57  * these.
  58  * @backlight: Turn backlight on or off. Optional.
  59  * @print: Print one character to the display at current cursor position.
  60  * The buffered cursor position is advanced by charlcd. The cursor should not
  61  * wrap to the next line at the end of a line.
  62  * @gotoxy: Set cursor to x, y. The x and y values to set the cursor to are
  63  * previously set in addr.x and addr.y by charlcd.
  64  * @home: Set cursor to 0, 0. The values in addr.x and addr.y are set to 0, 0 by
  65  * charlcd prior to calling this function.
  66  * @clear_display: Clear the whole display and set the cursor to 0, 0. The
  67  * values in addr.x and addr.y are set to 0, 0 by charlcd after to calling this
  68  * function.
  69  * @init_display: Initialize the display.
  70  * @shift_cursor: Shift cursor left or right one position.
  71  * @shift_display: Shift whole display content left or right.
  72  * @display: Turn display on or off.
  73  * @cursor: Turn cursor on or off.
  74  * @blink: Turn cursor blink on or off.
  75  * @lines: One or two lines.
  76  * @redefine_char: Redefine the actual pixel matrix of character.
  77  */
  78 struct charlcd_ops {
  79         void (*backlight)(struct charlcd *lcd, enum charlcd_onoff on);
  80         int (*print)(struct charlcd *lcd, int c);
  81         int (*gotoxy)(struct charlcd *lcd, unsigned int x, unsigned int y);
  82         int (*home)(struct charlcd *lcd);
  83         int (*clear_display)(struct charlcd *lcd);
  84         int (*init_display)(struct charlcd *lcd);
  85         int (*shift_cursor)(struct charlcd *lcd, enum charlcd_shift_dir dir);
  86         int (*shift_display)(struct charlcd *lcd, enum charlcd_shift_dir dir);
  87         int (*display)(struct charlcd *lcd, enum charlcd_onoff on);
  88         int (*cursor)(struct charlcd *lcd, enum charlcd_onoff on);
  89         int (*blink)(struct charlcd *lcd, enum charlcd_onoff on);
  90         int (*fontsize)(struct charlcd *lcd, enum charlcd_fontsize size);
  91         int (*lines)(struct charlcd *lcd, enum charlcd_lines lines);
  92         int (*redefine_char)(struct charlcd *lcd, char *esc);
  93 };
  94
  95 void charlcd_backlight(struct charlcd *lcd, enum charlcd_onoff on);
  96 struct charlcd *charlcd_alloc(void);
  97 void charlcd_free(struct charlcd *lcd);
  98
  99 int charlcd_register(struct charlcd *lcd);
 100 int charlcd_unregister(struct charlcd *lcd);
 101
 102 void charlcd_poke(struct charlcd *lcd);
 103
 104 #endif /* CHARLCD_H */