11 files changed, 335 insertions, 103 deletions

diff --git a/apps/lang/english.lang b/apps/lang/english.lang
index 09cbdbfc09..da09e3c49a 100644
--- a/apps/lang/english.lang
+++ b/apps/lang/english.lang
@@ -12405,7 +12405,7 @@
 </phrase>
 <phrase>
   id: LANG_TOUCHSCREEN_MODE
-  desc: in Settings -> General -> System menu
+  desc: in Settings -> General -> Display -> Touchscreen Settings
   user: core
   <source>
     *: none
@@ -12422,7 +12422,7 @@
 </phrase>
 <phrase>
   id: LANG_TOUCHSCREEN_GRID
-  desc: in Settings -> General -> System menu
+  desc: in Settings -> General -> Display -> Touchscreen Settings
   user: core
   <source>
     *: none
@@ -12439,7 +12439,7 @@
 </phrase>
 <phrase>
   id: LANG_TOUCHSCREEN_POINT
-  desc: in Settings -> General -> System menu
+  desc: in Settings -> General -> Display -> Touchscreen Settings
   user: core
   <source>
     *: none
@@ -12502,3 +12502,54 @@
     swcodec: "Speed"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_TOUCHSCREEN_SETTINGS
+  desc: in Settings -> General -> Display menu
+  user: core
+  <source>
+    *: none
+    touchscreen: "Touchscreen Settings"
+  </source>
+  <dest>
+    *: none
+    touchscreen: "Touchscreen Settings"
+  </dest>
+  <voice>
+    *: none
+    touchscreen: "Touchscreen Settings"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_TOUCHSCREEN_CALIBRATE
+  desc: in Settings -> General -> Display -> Touchscreen Settings
+  user: core
+  <source>
+    *: none
+    touchscreen: "Calibrate"
+  </source>
+  <dest>
+    *: none
+    touchscreen: "Calibrate"
+  </dest>
+  <voice>
+    *: none
+    touchscreen: "Calibrate"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_TOUCHSCREEN_RESET_CALIBRATION
+  desc: in Settings -> General -> Display -> Touchscreen Settings
+  user: core
+  <source>
+    *: none
+    touchscreen: "Reset Calibration"
+  </source>
+  <dest>
+    *: none
+    touchscreen: "Reset Calibration"
+  </dest>
+  <voice>
+    *: none
+    touchscreen: "Reset Calibration"
+  </voice>
+</phrase>
diff --git a/apps/lang/nederlands.lang b/apps/lang/nederlands.lang
index 2d476d1d14..e73839926f 100644
--- a/apps/lang/nederlands.lang
+++ b/apps/lang/nederlands.lang
@@ -12335,7 +12335,7 @@
 </phrase>
 <phrase>
   id: LANG_TOUCHSCREEN_MODE
-  desc: in Settings -> General -> System menu
+  desc: in Settings -> General -> Display -> Touchscreen Settings
   user: core
   <source>
     *: none
@@ -12352,7 +12352,7 @@
 </phrase>
 <phrase>
   id: LANG_TOUCHSCREEN_GRID
-  desc: in Settings -> General -> System menu
+  desc: in Settings -> General -> Display -> Touchscreen Settings
   user: core
   <source>
     *: none
@@ -12369,7 +12369,7 @@
 </phrase>
 <phrase>
   id: LANG_TOUCHSCREEN_POINT
-  desc: in Settings -> General -> System menu
+  desc: in Settings -> General -> Display -> Touchscreen Settings
   user: core
   <source>
     *: none
@@ -12432,3 +12432,54 @@
     swcodec: "Snelheid"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_TOUCHSCREEN_SETTINGS
+  desc: in Settings -> General -> Display menu
+  user: core
+  <source>
+    *: none
+    touchscreen: "Touchscreen Settings"
+  </source>
+  <dest>
+    *: none
+    touchscreen: "Touchscreen instellingen"
+  </dest>
+  <voice>
+    *: none
+    touchscreen: "Touchscreen instellingen"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_TOUCHSCREEN_CALIBRATE
+  desc: in Settings -> General -> Display -> Touchscreen Settings
+  user: core
+  <source>
+    *: none
+    touchscreen: "Calibrate"
+  </source>
+  <dest>
+    *: none
+    touchscreen: "Kalibreer"
+  </dest>
+  <voice>
+    *: none
+    touchscreen: "Kalibreer"
+  </voice>
+</phrase>
+<phrase>
+  id: LANG_TOUCHSCREEN_RESET_CALIBRATION
+  desc: in Settings -> General -> Display -> Touchscreen Settings
+  user: core
+  <source>
+    *: none
+    touchscreen: "Reset Calibration"
+  </source>
+  <dest>
+    *: none
+    touchscreen: "Kalibratie terugzetten"
+  </dest>
+  <voice>
+    *: none
+    touchscreen: "Kalibratie terugzetten"
+  </voice>
+</phrase>
diff --git a/apps/menus/display_menu.c b/apps/menus/display_menu.c
index a015be3a23..aee9c1828d 100644
--- a/apps/menus/display_menu.c
+++ b/apps/menus/display_menu.c
@@ -36,6 +36,9 @@
 #include "talk.h"
 #include "lcd.h"
 #include "lcd-remote.h"
+#ifdef HAVE_TOUCHSCREEN
+#include "screens.h"
+#endif
 
 #ifdef HAVE_BACKLIGHT
 static int filterfirstkeypress_callback(int action,const struct menu_item_ex *this_item)
@@ -496,6 +499,29 @@ MAKE_MENU(peak_meter_menu, ID2P(LANG_PM_MENU), NULL, Icon_NOICON,
 /***********************************/
 
 
+#ifdef HAVE_TOUCHSCREEN
+static int touch_mode_callback(int action,const struct menu_item_ex *this_item)
+{
+    (void)this_item;
+    switch (action)
+    {
+        case ACTION_EXIT_MENUITEM: /* on exit */
+            touchscreen_set_mode(global_settings.touch_mode);
+            break;
+    }
+    return action;
+}
+MENUITEM_SETTING(touch_mode, &global_settings.touch_mode, touch_mode_callback);
+
+MENUITEM_FUNCTION(touchscreen_menu_calibrate, 0, ID2P(LANG_TOUCHSCREEN_CALIBRATE), calibrate,
+                    NULL, NULL, Icon_NOICON);
+MENUITEM_FUNCTION(touchscreen_menu_reset_calibration, 0, ID2P(LANG_TOUCHSCREEN_RESET_CALIBRATION), reset_mapping,
+                    NULL, NULL, Icon_NOICON);
+
+MAKE_MENU(touchscreen_menu, ID2P(LANG_TOUCHSCREEN_SETTINGS), NULL, Icon_NOICON, &touch_mode,
+            &touchscreen_menu_calibrate, &touchscreen_menu_reset_calibration);
+#endif
+
 
 MENUITEM_SETTING(codepage_setting, &global_settings.default_codepage, NULL);
 
@@ -511,4 +537,7 @@ MAKE_MENU(display_menu, ID2P(LANG_DISPLAY),
             &bars_menu, &peak_meter_menu,
 #endif
             &codepage_setting,
+#ifdef HAVE_TOUCHSCREEN
+            &touchscreen_menu,
+#endif
             );
diff --git a/apps/menus/settings_menu.c b/apps/menus/settings_menu.c
index 56a0178000..fdc775877a 100644
--- a/apps/menus/settings_menu.c
+++ b/apps/menus/settings_menu.c
@@ -265,21 +265,6 @@ MENUITEM_SETTING(buttonlight_brightness, &global_settings.buttonlight_brightness
 MENUITEM_SETTING(touchpad_sensitivity, &global_settings.touchpad_sensitivity, NULL);
 #endif
 
-#ifdef HAVE_TOUCHSCREEN
-static int touch_mode_callback(int action,const struct menu_item_ex *this_item)
-{
-    (void)this_item;
-    switch (action)
-    {
-        case ACTION_EXIT_MENUITEM: /* on exit */
-            touchscreen_set_mode(global_settings.touch_mode);
-            break;
-    }
-    return action;
-}
-MENUITEM_SETTING(touch_mode, &global_settings.touch_mode, touch_mode_callback);
-#endif
-
 MAKE_MENU(system_menu, ID2P(LANG_SYSTEM),
           0, Icon_System_menu,
             &start_screen,
@@ -315,9 +300,6 @@ MAKE_MENU(system_menu, ID2P(LANG_SYSTEM),
 #ifdef HAVE_TOUCHPAD_SENSITIVITY_SETTING
             &touchpad_sensitivity,
 #endif
-#ifdef HAVE_TOUCHSCREEN
-            &touch_mode,
-#endif
          );
 
 /*    SYSTEM MENU                  */
diff --git a/apps/screens.c b/apps/screens.c
index 096b81411e..829aa191e1 100644
--- a/apps/screens.c
+++ b/apps/screens.c
@@ -1019,3 +1019,85 @@ bool view_runtime(void)
     }
     return false;
 }
+
+#ifdef HAVE_TOUCHSCREEN
+static int get_sample(struct touchscreen_calibration *cal, int x, int y, int i,
+                      struct screen* screen)
+{
+    int action;
+    short ts_x, ts_y;
+
+    /* Draw a cross */
+    screen->drawline(x - 10, y, x - 2, y);
+    screen->drawline(x + 2, y, x + 10, y);
+    screen->drawline(x, y - 10, x, y - 2);
+    screen->drawline(x, y + 2, x, y + 10);
+    screen->update();
+
+    /* Wait for a touchscreen press */
+    while(true)
+    {
+        action = get_action(CONTEXT_STD, TIMEOUT_BLOCK);
+        if(action == ACTION_TOUCHSCREEN)
+        {
+            if(action_get_touchscreen_press(&ts_x, &ts_y) == BUTTON_REL)
+                break;
+        }
+        else if(action == ACTION_STD_CANCEL)
+            return -1;
+    }
+
+    cal->x[i][0] = ts_x;
+    cal->y[i][0] = ts_y;
+    cal->x[i][1] = x;
+    cal->y[i][1] = y;
+
+    return 0;
+}
+
+
+int calibrate(void)
+{
+    short points[3][2] = {
+        {LCD_WIDTH/10, LCD_HEIGHT/10},
+        {7*LCD_WIDTH/8, LCD_HEIGHT/2},
+        {LCD_WIDTH/2, 7*LCD_HEIGHT/8}
+    };
+    struct screen* screen = &screens[SCREEN_MAIN];
+    enum touchscreen_mode old_mode = touchscreen_get_mode();
+    struct touchscreen_calibration cal;
+    int i, ret = 0;
+    bool statusbar = global_settings.statusbar; /* hide the statusbar */
+
+    global_settings.statusbar = false;
+    touchscreen_disable_mapping(); /* set raw mode */
+    touchscreen_set_mode(TOUCHSCREEN_POINT);
+    for(i=0; i<3; i++)
+    {
+        screen->clear_display();
+
+        if(get_sample(&cal, points[i][0], points[i][1], i, screen))
+        {
+            ret = -1;
+            break;
+        }
+    }
+
+    if(ret == 0)
+        touchscreen_calibrate(&cal);
+    else
+        touchscreen_reset_mapping();
+    memcpy(&global_settings.ts_calibration_data, &calibration_parameters, sizeof(struct touchscreen_parameter));
+    touchscreen_set_mode(old_mode);
+    global_settings.statusbar = statusbar;
+
+    return ret;
+}
+
+int reset_mapping(void)
+{
+    touchscreen_reset_mapping();
+    memcpy(&global_settings.ts_calibration_data, &calibration_parameters, sizeof(struct touchscreen_parameter));
+    return 0;
+}
+#endif
diff --git a/apps/screens.h b/apps/screens.h
index eb613fc178..38fef14d60 100644
--- a/apps/screens.h
+++ b/apps/screens.h
@@ -50,5 +50,10 @@ bool shutdown_screen(void);
 bool browse_id3(void);
 bool view_runtime(void);
 
+#ifdef HAVE_TOUCHSCREEN
+int calibrate(void);
+int reset_mapping(void);
+#endif
+
 #endif
 
diff --git a/apps/settings.c b/apps/settings.c
index 9594bd164e..3219dbbf12 100644
--- a/apps/settings.c
+++ b/apps/settings.c
@@ -966,6 +966,7 @@ void settings_apply(bool read_disk)
 
 #ifdef HAVE_TOUCHSCREEN
     touchscreen_set_mode(global_settings.touch_mode);
+    memcpy(&calibration_parameters, &global_settings.ts_calibration_data, sizeof(struct touchscreen_parameter));
 #endif
 
     /* This should stay last */
diff --git a/apps/settings.h b/apps/settings.h
index 6ccaeed92e..ef5a62013d 100644
--- a/apps/settings.h
+++ b/apps/settings.h
@@ -730,6 +730,7 @@ struct user_settings
 
 #ifdef HAVE_TOUCHSCREEN
     int touch_mode;
+    struct touchscreen_parameter ts_calibration_data;
 #endif
 
     /* If values are just added to the end, no need to bump plugin API
diff --git a/apps/settings_list.c b/apps/settings_list.c
index 74e2cab3cd..dcad718ee5 100644
--- a/apps/settings_list.c
+++ b/apps/settings_list.c
@@ -53,6 +53,10 @@
 #include "iap.h"
 #endif
 #include "statusbar.h"
+#ifdef HAVE_TOUCHSCREEN
+#include "touchscreen.h"
+#include "ctype.h" /* For isspace() */
+#endif
 
 #define NVRAM(bytes) (bytes<<F_NVRAM_MASK_SHIFT)
 /** NOTE: NVRAM_CONFIG_VERSION is in settings_list.h
@@ -452,6 +456,48 @@ static void qs_set_default(void* setting, void* defaultval)
     find_setting(defaultval, (int*)setting);
 }
 #endif
+#ifdef HAVE_TOUCHSCREEN
+static void tsc_load_from_cfg(void* setting, char*value)
+{
+    struct touchscreen_parameter *var = (struct touchscreen_parameter*) setting;
+
+    /* Replacement for sscanf(value, "%d ..., &var->A, ...); */
+    int vals[7], count = 0;
+    while(*value != 0 && count < 7)
+    {
+        if(isspace(*value))
+            value++;
+        else
+        {
+            vals[count++] = atoi(value);
+            while(!isspace(*value))
+                value++;
+        }
+    }
+    var->A = vals[0];
+    var->B = vals[1];
+    var->C = vals[2];
+    var->D = vals[3];
+    var->E = vals[4];
+    var->F = vals[5];
+    var->divider = vals[6];
+}
+
+static char* tsc_write_to_cfg(void* setting, char*buf, int buf_len)
+{
+    const struct touchscreen_parameter *var = (const struct touchscreen_parameter*) setting;
+    snprintf(buf, buf_len, "%d %d %d %d %d %d %d", var->A, var->B, var->C, var->D, var->E, var->F, var->divider);
+    return buf;
+}
+static bool tsc_is_changed(void* setting, void* defaultval)
+{
+    return memcmp(setting, defaultval, sizeof(struct touchscreen_parameter)) != 0;
+}
+static void tsc_set_default(void* setting, void* defaultval)
+{
+    memcpy(setting, defaultval, sizeof(struct touchscreen_parameter));
+}
+#endif
 const struct settings_list settings[] = {
     /* sound settings */
     SOUND_SETTING(F_NO_WRAP,volume, LANG_VOLUME, "volume", SOUND_VOLUME),
@@ -1470,6 +1516,10 @@ const struct settings_list settings[] = {
     CHOICE_SETTING(0, touch_mode, LANG_TOUCHSCREEN_MODE, TOUCHSCREEN_BUTTON,
                    "touchscreen mode", "point,grid", NULL, 2,
                    ID2P(LANG_TOUCHSCREEN_POINT), ID2P(LANG_TOUCHSCREEN_GRID)),
+    CUSTOM_SETTING(0, ts_calibration_data, -1, 
+                    &default_calibration_parameters, "touchscreen calibration",
+                    tsc_load_from_cfg, tsc_write_to_cfg,
+                    tsc_is_changed, tsc_set_default),
 #endif
     OFFON_SETTING(0, prevent_skip, LANG_PREVENT_SKIPPING, false, "prevent track skip", NULL),
 };
diff --git a/firmware/drivers/touchscreen.c b/firmware/drivers/touchscreen.c
index f7b1b09b92..002acf1236 100755
--- a/firmware/drivers/touchscreen.c
+++ b/firmware/drivers/touchscreen.c
@@ -34,119 +34,93 @@ static const int touchscreen_buttons[3][3] =
     {BUTTON_BOTTOMLEFT, BUTTON_BOTTOMMIDDLE, BUTTON_BOTTOMRIGHT}
 };
 
-/* Based on ftp://ftp.embedded.com/pub/2002/06vidales/calibrate.c
- *
- *   Copyright (c) 2001, Carlos E. Vidales. All rights reserved.
- *
- *   This sample program was written and put in the public domain 
- *    by Carlos E. Vidales.  The program is provided "as is" 
- *    without warranty of any kind, either expressed or implied.
- *   If you choose to use the program within your own products
- *    you do so at your own risk, and assume the responsibility
- *    for servicing, repairing or correcting the program should
- *    it prove defective in any manner.
- *   You may copy and distribute the program's source code in any 
- *    medium, provided that you also include in each copy an
- *    appropriate copyright notice and disclaimer of warranty.
- *   You may also modify this program and distribute copies of
- *    it provided that you include prominent notices stating 
- *    that you changed the file(s) and the date of any change,
- *    and that you do not charge any royalties or licenses for 
- *    its use.
- */
-struct touchscreen_parameter
-{
-    long A;
-    long B;
-    long C;
-    long D;
-    long E;
-    long F;
-    long divider;
-};
-
 #ifndef DEFAULT_TOUCHSCREEN_CALIBRATION
-#define DEFAULT_TOUCHSCREEN_CALIBRATION {.A=1, .B=0, .C=0, \
-                                         .D=0, .E=1, .F=0, \
-                                         .divider=1}
+#define DEFAULT_TOUCHSCREEN_CALIBRATION { .A=1, .B=0, .C=0, \
+                                          .D=0, .E=1, .F=0, \
+                                          .divider=1 }
 #endif
 
-static struct touchscreen_parameter calibration_parameters
+struct touchscreen_parameter calibration_parameters
                                               = DEFAULT_TOUCHSCREEN_CALIBRATION;
-static const struct touchscreen_parameter default_parameters
+const struct touchscreen_parameter default_calibration_parameters
                                               = DEFAULT_TOUCHSCREEN_CALIBRATION;
 
 void touchscreen_disable_mapping(void)
 {
-    calibration_parameters.A = 1;
-    calibration_parameters.B = 0;
-    calibration_parameters.C = 0;
-    calibration_parameters.D = 0;
-    calibration_parameters.E = 1;
-    calibration_parameters.F = 0;
-    calibration_parameters.divider = 1;
+#define C(x) calibration_parameters.x
+    C(A) = C(E) = 1;
+    C(B) = C(C) = C(D) = C(F) = 0;
+    C(divider) = 1;
+#undef C
 }
 
 void touchscreen_reset_mapping(void)
 {
-    memcpy(&calibration_parameters, &default_parameters,
+    memcpy(&calibration_parameters, &default_calibration_parameters,
            sizeof(struct touchscreen_parameter));
 }
 
 int touchscreen_calibrate(struct touchscreen_calibration *cal)
 {
-    calibration_parameters.divider = ((cal->x[0] - cal->x[2]) * (cal->y[1] - cal->y[2])) - 
-                                     ((cal->x[1] - cal->x[2]) * (cal->y[0] - cal->y[2])) ;
+#define C(x)   calibration_parameters.x /* Calibration */
+#define S(i,j) cal->i[j][0]             /* Screen */
+#define D(i,j) cal->i[j][1]             /* Display */
+    long divider = (S(x,0) - S(x,2)) * (S(y,1) - S(y,2)) -
+                   (S(x,1) - S(x,2)) * (S(y,0) - S(y,2));
 
-    if(calibration_parameters.divider == 0)
+    if(divider == 0)
         return -1;
-    
-    calibration_parameters.A = ((cal->xfb[0] - cal->xfb[2]) * (cal->y[1] - cal->y[2])) - 
-                               ((cal->xfb[1] - cal->xfb[2]) * (cal->y[0] - cal->y[2])) ;
+    else
+        C(divider) = divider;
 
-    calibration_parameters.B = ((cal->x[0]   - cal->x[2])   * (cal->xfb[1] - cal->xfb[2])) - 
-                               ((cal->xfb[0] - cal->xfb[2]) * (cal->x[1]   - cal->x[2])) ;
+    C(A) = (D(x,0) - D(x,2)) * (S(y,1) - S(y,2)) -
+           (D(x,1) - D(x,2)) * (S(y,0) - S(y,2));
 
-    calibration_parameters.C = (cal->x[2] * cal->xfb[1] - cal->x[1] * cal->xfb[2]) * cal->y[0] +
-                               (cal->x[0] * cal->xfb[2] - cal->x[2] * cal->xfb[0]) * cal->y[1] +
-                               (cal->x[1] * cal->xfb[0] - cal->x[0] * cal->xfb[1]) * cal->y[2] ;
+    C(B) = (S(x,0) - S(x,2)) * (D(x,1) - D(x,2)) -
+           (D(x,0) - D(x,2)) * (S(x,1) - S(x,2));
 
-    calibration_parameters.D = ((cal->yfb[0] - cal->yfb[2]) * (cal->y[1] - cal->y[2])) - 
-                               ((cal->yfb[1] - cal->yfb[2]) * (cal->y[0] - cal->y[2])) ;
+    C(C) = S(y,0) * (S(x,2) * D(x,1) - S(x,1) * D(x,2)) +
+           S(y,1) * (S(x,0) * D(x,2) - S(x,2) * D(x,0)) +
+           S(y,2) * (S(x,1) * D(x,0) - S(x,0) * D(x,1));
 
-    calibration_parameters.E = ((cal->x[0]   - cal->x[2])   * (cal->yfb[1] - cal->yfb[2])) - 
-                               ((cal->yfb[0] - cal->yfb[2]) * (cal->x[1]   - cal->x[2])) ;
+    C(D) = (D(y,0) - D(y,2)) * (S(y,1) - S(y,2)) -
+           (D(y,1) - D(y,2)) * (S(y,0) - S(y,2));
 
-    calibration_parameters.F = (cal->x[2] * cal->yfb[1] - cal->x[1] * cal->yfb[2]) * cal->y[0] +
-                               (cal->x[0] * cal->yfb[2] - cal->x[2] * cal->yfb[0]) * cal->y[1] +
-                               (cal->x[1] * cal->yfb[0] - cal->x[0] * cal->yfb[1]) * cal->y[2] ;
+    C(E) = (S(x,0) - S(x,2)) * (D(y,1) - D(y,2)) -
+           (D(y,0) - D(y,2)) * (S(x,1) - S(x,2));
+
+    C(F) = S(y,0) * (S(x,2) * D(y,1) - S(x,1) * D(y,2)) +
+           S(y,1) * (S(x,0) * D(y,2) - S(x,2) * D(y,0)) +
+           S(y,2) * (S(x,1) * D(y,0) - S(x,0) * D(y,1));
+
+    logf("A: %lX B: %lX C: %lX", C(A), C(B), C(C));
+    logf("D: %lX E: %lX F: %lX", C(D), C(E), C(F));
+    logf("divider: %lX", C(divider));
 
-    logf("A: %lX B: %lX C: %lX", calibration_parameters.A,
-         calibration_parameters.B, calibration_parameters.C);
-    logf("D: %lX E: %lX F: %lX", calibration_parameters.D,
-         calibration_parameters.E, calibration_parameters.F);
-    logf("divider: %lX", calibration_parameters.divider);
-    
     return 0;
+#undef C
+#undef S
+#undef D
 }
 
 static void map_pixels(int *x, int *y)
 {
+#define C(x) calibration_parameters.x
     int _x = *x, _y = *y;
-    
-    *x = (calibration_parameters.A*_x + calibration_parameters.B*_y +
-          calibration_parameters.C) / calibration_parameters.divider;
-    *y = (calibration_parameters.D*_x + calibration_parameters.E*_y +
-          calibration_parameters.F) / calibration_parameters.divider;
+
+    *x = (C(A) * _x + C(B) * _y + C(C)) / C(divider);
+    *y = (C(D) * _x + C(E) * _y + C(F)) / C(divider);
+#undef C
 }
 
+/* TODO: add jitter (and others) filter */
 int touchscreen_to_pixels(int x, int y, int *data)
 {
     x &= 0xFFFF;
     y &= 0xFFFF;
-    
+
     map_pixels(&x, &y);
-    
+
     if(current_mode == TOUCHSCREEN_BUTTON)
         return touchscreen_buttons[y / (LCD_HEIGHT/3)]
                                   [x / (LCD_WIDTH/3) ];
diff --git a/firmware/export/touchscreen.h b/firmware/export/touchscreen.h
index 0d8233a522..7d1eb4ac8a 100755
--- a/firmware/export/touchscreen.h
+++ b/firmware/export/touchscreen.h
@@ -24,10 +24,14 @@
 
 struct touchscreen_calibration
 {
-    int   x[3];
-    int xfb[3];
-    int   y[3];
-    int yfb[3];
+    int x[3][2];
+    int y[3][2];
+};
+
+struct touchscreen_parameter
+{
+    int A, B, C, D, E, F;
+    int divider;
 };
 
 enum touchscreen_mode
@@ -38,6 +42,8 @@ enum touchscreen_mode
                               from button_get_data */
 };
 
+extern struct touchscreen_parameter calibration_parameters;
+extern const struct touchscreen_parameter default_calibration_parameters;
 int touchscreen_calibrate(struct touchscreen_calibration *cal);
 int touchscreen_to_pixels(int x, int y, int *data);
 void touchscreen_set_mode(enum touchscreen_mode mode);