firmware/drivers/touchscreen.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2008 by Maurus Cuelenaere
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21
  22 #include "config.h"
  23 #include "button.h"
  24 #include "button-target.h"
  25 #include "touchscreen.h"
  26 #include "string.h"
  27 #include "logf.h"
  28
  29 static enum touchscreen_mode current_mode = TOUCHSCREEN_POINT;
  30 static const int touchscreen_buttons[3][3] =
  31 {
  32     {BUTTON_TOPLEFT,    BUTTON_TOPMIDDLE,    BUTTON_TOPRIGHT},
  33     {BUTTON_MIDLEFT,    BUTTON_CENTER,       BUTTON_MIDRIGHT},
  34     {BUTTON_BOTTOMLEFT, BUTTON_BOTTOMMIDDLE, BUTTON_BOTTOMRIGHT}
  35 };
  36
  37 #ifndef DEFAULT_TOUCHSCREEN_CALIBRATION
  38 #define DEFAULT_TOUCHSCREEN_CALIBRATION { .A=1, .B=0, .C=0, \
  39                                           .D=0, .E=1, .F=0, \
  40                                           .divider=1 }
  41 #endif
  42
  43 struct touchscreen_parameter calibration_parameters
  44                                               = DEFAULT_TOUCHSCREEN_CALIBRATION;
  45 const struct touchscreen_parameter default_calibration_parameters
  46                                               = DEFAULT_TOUCHSCREEN_CALIBRATION;
  47
  48 void touchscreen_disable_mapping(void)
  49 {
  50 #define C(x) calibration_parameters.x
  51     C(A) = C(E) = 1;
  52     C(B) = C(C) = C(D) = C(F) = 0;
  53     C(divider) = 1;
  54 #undef C
  55 }
  56
  57 void touchscreen_reset_mapping(void)
  58 {
  59     memcpy(&calibration_parameters, &default_calibration_parameters,
  60            sizeof(struct touchscreen_parameter));
  61 }
  62
  63 int touchscreen_calibrate(struct touchscreen_calibration *cal)
  64 {
  65 #define C(x)   calibration_parameters.x /* Calibration */
  66 #define S(i,j) cal->i[j][0]             /* Screen */
  67 #define D(i,j) cal->i[j][1]             /* Display */
  68     long divider = (S(x,0) - S(x,2)) * (S(y,1) - S(y,2)) -
  69                    (S(x,1) - S(x,2)) * (S(y,0) - S(y,2));
  70
  71     if(divider == 0)
  72         return -1;
  73     else
  74         C(divider) = divider;
  75
  76     C(A) = (D(x,0) - D(x,2)) * (S(y,1) - S(y,2)) -
  77            (D(x,1) - D(x,2)) * (S(y,0) - S(y,2));
  78
  79     C(B) = (S(x,0) - S(x,2)) * (D(x,1) - D(x,2)) -
  80            (D(x,0) - D(x,2)) * (S(x,1) - S(x,2));
  81
  82     C(C) = S(y,0) * (S(x,2) * D(x,1) - S(x,1) * D(x,2)) +
  83            S(y,1) * (S(x,0) * D(x,2) - S(x,2) * D(x,0)) +
  84            S(y,2) * (S(x,1) * D(x,0) - S(x,0) * D(x,1));
  85
  86     C(D) = (D(y,0) - D(y,2)) * (S(y,1) - S(y,2)) -
  87            (D(y,1) - D(y,2)) * (S(y,0) - S(y,2));
  88
  89     C(E) = (S(x,0) - S(x,2)) * (D(y,1) - D(y,2)) -
  90            (D(y,0) - D(y,2)) * (S(x,1) - S(x,2));
  91
  92     C(F) = S(y,0) * (S(x,2) * D(y,1) - S(x,1) * D(y,2)) +
  93            S(y,1) * (S(x,0) * D(y,2) - S(x,2) * D(y,0)) +
  94            S(y,2) * (S(x,1) * D(y,0) - S(x,0) * D(y,1));
  95
  96     logf("A: %lX B: %lX C: %lX", C(A), C(B), C(C));
  97     logf("D: %lX E: %lX F: %lX", C(D), C(E), C(F));
  98     logf("divider: %lX", C(divider));
  99
 100     return 0;
 101 #undef C
 102 #undef S
 103 #undef D
 104 }
 105
 106 static void map_pixels(int *x, int *y)
 107 {
 108 #define C(x) calibration_parameters.x
 109     int _x = *x, _y = *y;
 110
 111     *x = (C(A) * _x + C(B) * _y + C(C)) / C(divider);
 112     *y = (C(D) * _x + C(E) * _y + C(F)) / C(divider);
 113 #undef C
 114 }
 115
 116 /* TODO: add jitter (and others) filter */
 117 int touchscreen_to_pixels(int x, int y, int *data)
 118 {
 119     x &= 0xFFFF;
 120     y &= 0xFFFF;
 121
 122     map_pixels(&x, &y);
 123
 124     if(current_mode == TOUCHSCREEN_BUTTON)
 125         return touchscreen_buttons[y / (LCD_HEIGHT/3)]
 126                                   [x / (LCD_WIDTH/3) ];
 127     else
 128     {
 129         *data = (x << 16 | y);
 130         return BUTTON_TOUCHSCREEN;
 131     }
 132 }
 133
 134 void touchscreen_set_mode(enum touchscreen_mode mode)
 135 {
 136     current_mode = mode;
 137 }
 138
 139 enum touchscreen_mode touchscreen_get_mode(void)
 140 {
 141     return current_mode;
 142 }