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 /* Based on ftp://ftp.embedded.com/pub/2002/06vidales/calibrate.c
  38  *
  39  *   Copyright (c) 2001, Carlos E. Vidales. All rights reserved.
  40  *
  41  *   This sample program was written and put in the public domain
  42  *    by Carlos E. Vidales.  The program is provided "as is"
  43  *    without warranty of any kind, either expressed or implied.
  44  *   If you choose to use the program within your own products
  45  *    you do so at your own risk, and assume the responsibility
  46  *    for servicing, repairing or correcting the program should
  47  *    it prove defective in any manner.
  48  *   You may copy and distribute the program's source code in any
  49  *    medium, provided that you also include in each copy an
  50  *    appropriate copyright notice and disclaimer of warranty.
  51  *   You may also modify this program and distribute copies of
  52  *    it provided that you include prominent notices stating
  53  *    that you changed the file(s) and the date of any change,
  54  *    and that you do not charge any royalties or licenses for
  55  *    its use.
  56  */
  57 struct touchscreen_parameter
  58 {
  59     long A;
  60     long B;
  61     long C;
  62     long D;
  63     long E;
  64     long F;
  65     long divider;
  66 };
  67
  68 #ifndef DEFAULT_TOUCHSCREEN_CALIBRATION
  69 #define DEFAULT_TOUCHSCREEN_CALIBRATION {.A=1, .B=0, .C=0, \
  70                                          .D=0, .E=1, .F=0, \
  71                                          .divider=1}
  72 #endif
  73
  74 static struct touchscreen_parameter calibration_parameters
  75                                               = DEFAULT_TOUCHSCREEN_CALIBRATION;
  76 static const struct touchscreen_parameter default_parameters
  77                                               = DEFAULT_TOUCHSCREEN_CALIBRATION;
  78
  79 void touchscreen_disable_mapping(void)
  80 {
  81     calibration_parameters.A = 1;
  82     calibration_parameters.B = 0;
  83     calibration_parameters.C = 0;
  84     calibration_parameters.D = 0;
  85     calibration_parameters.E = 1;
  86     calibration_parameters.F = 0;
  87     calibration_parameters.divider = 1;
  88 }
  89
  90 void touchscreen_reset_mapping(void)
  91 {
  92     memcpy(&calibration_parameters, &default_parameters,
  93            sizeof(struct touchscreen_parameter));
  94 }
  95
  96 int touchscreen_calibrate(struct touchscreen_calibration *cal)
  97 {
  98     calibration_parameters.divider = ((cal->x[0] - cal->x[2]) * (cal->y[1] - cal->y[2])) -
  99                                      ((cal->x[1] - cal->x[2]) * (cal->y[0] - cal->y[2])) ;
 100
 101     if(calibration_parameters.divider == 0)
 102         return -1;
 103
 104     calibration_parameters.A = ((cal->xfb[0] - cal->xfb[2]) * (cal->y[1] - cal->y[2])) -
 105                                ((cal->xfb[1] - cal->xfb[2]) * (cal->y[0] - cal->y[2])) ;
 106
 107     calibration_parameters.B = ((cal->x[0]   - cal->x[2])   * (cal->xfb[1] - cal->xfb[2])) -
 108                                ((cal->xfb[0] - cal->xfb[2]) * (cal->x[1]   - cal->x[2])) ;
 109
 110     calibration_parameters.C = (cal->x[2] * cal->xfb[1] - cal->x[1] * cal->xfb[2]) * cal->y[0] +
 111                                (cal->x[0] * cal->xfb[2] - cal->x[2] * cal->xfb[0]) * cal->y[1] +
 112                                (cal->x[1] * cal->xfb[0] - cal->x[0] * cal->xfb[1]) * cal->y[2] ;
 113
 114     calibration_parameters.D = ((cal->yfb[0] - cal->yfb[2]) * (cal->y[1] - cal->y[2])) -
 115                                ((cal->yfb[1] - cal->yfb[2]) * (cal->y[0] - cal->y[2])) ;
 116
 117     calibration_parameters.E = ((cal->x[0]   - cal->x[2])   * (cal->yfb[1] - cal->yfb[2])) -
 118                                ((cal->yfb[0] - cal->yfb[2]) * (cal->x[1]   - cal->x[2])) ;
 119
 120     calibration_parameters.F = (cal->x[2] * cal->yfb[1] - cal->x[1] * cal->yfb[2]) * cal->y[0] +
 121                                (cal->x[0] * cal->yfb[2] - cal->x[2] * cal->yfb[0]) * cal->y[1] +
 122                                (cal->x[1] * cal->yfb[0] - cal->x[0] * cal->yfb[1]) * cal->y[2] ;
 123
 124     logf("A: %lX B: %lX C: %lX", calibration_parameters.A,
 125          calibration_parameters.B, calibration_parameters.C);
 126     logf("D: %lX E: %lX F: %lX", calibration_parameters.D,
 127          calibration_parameters.E, calibration_parameters.F);
 128     logf("divider: %lX", calibration_parameters.divider);
 129
 130     return 0;
 131 }
 132
 133 static void map_pixels(int *x, int *y)
 134 {
 135     int _x = *x, _y = *y;
 136
 137     *x = (calibration_parameters.A*_x + calibration_parameters.B*_y +
 138           calibration_parameters.C) / calibration_parameters.divider;
 139     *y = (calibration_parameters.D*_x + calibration_parameters.E*_y +
 140           calibration_parameters.F) / calibration_parameters.divider;
 141 }
 142
 143 int touchscreen_to_pixels(int x, int y, int *data)
 144 {
 145     x &= 0xFFFF;
 146     y &= 0xFFFF;
 147
 148     map_pixels(&x, &y);
 149
 150     if(current_mode == TOUCHSCREEN_BUTTON)
 151         return touchscreen_buttons[y / (LCD_HEIGHT/3)]
 152                                   [x / (LCD_WIDTH/3) ];
 153     else
 154     {
 155         *data = (x << 16 | y);
 156         return BUTTON_TOUCHSCREEN;
 157     }
 158 }
 159
 160 void touchscreen_set_mode(enum touchscreen_mode mode)
 161 {
 162     current_mode = mode;
 163 }
 164
 165 enum touchscreen_mode touchscreen_get_mode(void)
 166 {
 167     return current_mode;
 168 }