diff --git a/apps/gui/icon.h b/apps/gui/icon.h
index 119ee3cc47..8fe7262ffe 100644
--- a/apps/gui/icon.h
+++ b/apps/gui/icon.h
@@ -24,9 +24,9 @@
 /* Defines a type for the icons since it's not the same thing on
  * char-based displays and bitmap displays */
 #ifdef HAVE_LCD_BITMAP
-    #define ICON const unsigned char *
+    typedef const unsigned char * ICON;
 #else
-    #define ICON unsigned short
+    typedef unsigned short ICON;
 #endif
 
 #define CURSOR_CHAR 0x92
diff --git a/apps/gui/list.c b/apps/gui/list.c
index 1a83a65e64..ed26f1c9a8 100644
--- a/apps/gui/list.c
+++ b/apps/gui/list.c
@@ -39,8 +39,12 @@
 
 
 void gui_list_init(struct gui_list * gui_list,
-         void (*callback_get_item_icon)(int selected_item, ICON * icon),
-         char * (*callback_get_item_name)(int selected_item, char *buffer))
+    void (*callback_get_item_icon)
+        (int selected_item, void * data, ICON * icon),
+    char * (*callback_get_item_name)
+        (int selected_item, void * data, char *buffer),
+    void * data
+    )
 {
     gui_list->callback_get_item_icon = callback_get_item_icon;
     gui_list->callback_get_item_name = callback_get_item_name;
@@ -48,12 +52,8 @@ void gui_list_init(struct gui_list * gui_list,
     gui_list_set_nb_items(gui_list, 0);
     gui_list->selected_item = 0;
     gui_list->start_item = 0;
-    gui_list->limit_scroll=false;
-}
-
-inline void gui_list_set_nb_items(struct gui_list * gui_list, int nb_items)
-{
-    gui_list->nb_items = nb_items;
+    gui_list->limit_scroll = false;
+    gui_list->data=data;
 }
 
 void gui_list_set_display(struct gui_list * gui_list, struct screen * display)
@@ -70,30 +70,25 @@ void gui_list_set_display(struct gui_list * gui_list, struct screen * display)
 void gui_list_put_selection_in_screen(struct gui_list * gui_list,
                                       bool put_from_end)
 {
-    struct screen * display = gui_list->display;
+    int nb_lines=gui_list->display->nb_lines;
     if(put_from_end)
     {
         int list_end = gui_list->selected_item + SCROLL_LIMIT - 1;
         if(list_end > gui_list->nb_items)
-            list_end = gui_list->nb_items;
-        gui_list->start_item = list_end - display->nb_lines;
+            list_end = nb_lines;
+        gui_list->start_item = list_end - nb_lines;
     }
     else
     {
         int list_start = gui_list->selected_item - SCROLL_LIMIT + 1;
-        if(list_start + display->nb_lines > gui_list->nb_items)
-            list_start = gui_list->nb_items - display->nb_lines;
+        if(list_start + nb_lines > gui_list->nb_items)
+            list_start = gui_list->nb_items - nb_lines;
         gui_list->start_item = list_start;
     }
     if(gui_list->start_item < 0)
         gui_list->start_item = 0;
 }
 
-inline int gui_list_get_sel_pos(struct gui_list * gui_list)
-{
-    return gui_list->selected_item;
-}
-
 void gui_list_draw(struct gui_list * gui_list)
 {
     struct screen * display=gui_list->display;
@@ -117,13 +112,13 @@ void gui_list_draw(struct gui_list * gui_list)
     text_pos = 0; /* here it's in pixels */
     if(draw_scrollbar)
     {
-        ++cursor_pos;
-        ++icon_pos;
+        cursor_pos++;
+        icon_pos++;
         text_pos += SCROLLBAR_WIDTH;
     }
     if(!draw_cursor)
     {
-        --icon_pos;
+        icon_pos--;
     }
     else
         text_pos += CURSOR_WIDTH;
@@ -165,6 +160,7 @@ void gui_list_draw(struct gui_list * gui_list)
         if(current_item >= gui_list->nb_items)
             break;
         entry_name = gui_list->callback_get_item_name(current_item,
+                                                      gui_list->data,
                                                       entry_buffer);
         if(current_item == gui_list->selected_item)
         {
@@ -193,7 +189,9 @@ void gui_list_draw(struct gui_list * gui_list)
         if(draw_icons)
         {
             ICON icon;
-            gui_list->callback_get_item_icon(current_item, &icon);
+            gui_list->callback_get_item_icon(current_item,
+                                             gui_list->data,
+                                             &icon);
             screen_put_iconxy(display, icon_pos, i, icon);
         }
     }
@@ -234,7 +232,7 @@ void gui_list_select_next(struct gui_list * gui_list)
     {
         if(gui_list->limit_scroll)
             return;
-        ++gui_list->selected_item;
+        gui_list->selected_item++;
         /* we have already reached the bottom of the list */
         gui_list->selected_item = 0;
         gui_list->start_item = 0;
@@ -242,14 +240,14 @@ void gui_list_select_next(struct gui_list * gui_list)
     else
     {
         int nb_lines = gui_list->display->nb_lines;
-        ++gui_list->selected_item;
+        gui_list->selected_item++;
         item_pos = gui_list->selected_item - gui_list->start_item;
         end_item = gui_list->start_item + nb_lines;
         /* we start scrolling vertically when reaching the line
          * (nb_lines-SCROLL_LIMIT)
          * and when we are not in the last part of the list*/
         if( item_pos > nb_lines-SCROLL_LIMIT && end_item < gui_list->nb_items )
-            ++gui_list->start_item;
+            gui_list->start_item++;
     }
 }
 
@@ -262,7 +260,7 @@ void gui_list_select_previous(struct gui_list * gui_list)
     {
         if(gui_list->limit_scroll)
             return;
-        --gui_list->selected_item;
+        gui_list->selected_item--;
         /* we have aleady reached the top of the list */
         int start;
         gui_list->selected_item = gui_list->nb_items-1;
@@ -274,10 +272,10 @@ void gui_list_select_previous(struct gui_list * gui_list)
     }
     else
     {
-         --gui_list->selected_item;
+        gui_list->selected_item--;
         item_pos = gui_list->selected_item - gui_list->start_item;
         if( item_pos < SCROLL_LIMIT-1 && gui_list->start_item > 0 )
-            --gui_list->start_item;
+            gui_list->start_item--;
     }
 }
 
@@ -317,7 +315,7 @@ void gui_list_select_previous_page(struct gui_list * gui_list, int nb_lines)
 
 void gui_list_add_item(struct gui_list * gui_list)
 {
-    ++gui_list->nb_items;
+    gui_list->nb_items++;
     /* if only one item in the list, select it */
     if(gui_list->nb_items == 1)
         gui_list->selected_item = 0;
@@ -337,34 +335,35 @@ void gui_list_del_item(struct gui_list * gui_list)
         {
             /* Oops we are removing the selected item,
                select the previous one */
-            --gui_list->selected_item;
+            gui_list->selected_item--;
         }
-        --gui_list->nb_items;
+        gui_list->nb_items--;
 
         /* scroll the list if needed */
         if( (dist_start_from_end < nb_lines) && (gui_list->start_item != 0) )
-            --gui_list->start_item;
+            gui_list->start_item--;
     }
 }
 
-inline void gui_list_limit_scroll(struct gui_list * gui_list, bool scroll)
-{
-    gui_list->limit_scroll=scroll;
-}
 /*
  * Synchronized lists stuffs
  */
 void gui_synclist_init(
     struct gui_synclist * lists,
-    void (*callback_get_item_icon)(int selected_item, ICON * icon),
-    char * (*callback_get_item_name)(int selected_item, char *buffer)
+    void (*callback_get_item_icon)
+        (int selected_item, void * data, ICON * icon),
+    char * (*callback_get_item_name)
+        (int selected_item, void * data, char *buffer),
+    void * data
     )
 {
     int i;
     for(i = 0;i < NB_SCREENS;i++)
     {
-        gui_list_init(&(lists->gui_list[i]), callback_get_item_icon,
-                      callback_get_item_name);
+        gui_list_init(&(lists->gui_list[i]),
+                      callback_get_item_icon,
+                      callback_get_item_name,
+                      data);
         gui_list_set_display(&(lists->gui_list[i]), &(screens[i]));
     }
 }
@@ -378,11 +377,6 @@ void gui_synclist_set_nb_items(struct gui_synclist * lists, int nb_items)
     }
 }
 
-int gui_synclist_get_sel_pos(struct gui_synclist * lists)
-{
-    return gui_list_get_sel_pos(&(lists->gui_list[0]));
-}
-
 void gui_synclist_draw(struct gui_synclist * lists)
 {
     int i;
diff --git a/apps/gui/list.h b/apps/gui/list.h
index e47f260a1b..4472fadbf8 100644
--- a/apps/gui/list.h
+++ b/apps/gui/list.h
@@ -63,21 +63,50 @@
 #define LIST_PGDN      (BUTTON_ON | BUTTON_DOWN)
 #endif
 
-
+/*
+ * The gui_list is based on callback functions, if you want the list
+ * to display something you have to provide it a function that
+ * tells it what to display.
+ * There are two callback function :
+ * one to get the text and one to get the icon
+ * Callback interface :
+ *
+ * Text callback
+ *  - selected_item : an integer that tells the number of the item to display
+ *  - data : a void pointer to the data you gave to the list when
+ *           you initialized it
+ *  - buffer : a buffer to put the resulting text on it
+ *             (The content of the buffer may not be used by the list, we use
+ *             the return value of the function in all cases to avoid filling
+ *             a buffer when it's not necessary)
+ * Returns a pointer to a string that contains the text to display
+ *
+ * Icon callback
+ *  - selected_item : an integer that tells the number of the item to display
+ *  - data : a void pointer to the data you gave to the list when
+ *           you initialized it
+ *  - icon : a pointer to the icon, the value inside it is used to display
+ *           the icon after the function returns.
+ * Note : we use the ICON type because the real type depends of the plateform
+ */
 struct gui_list
 {
     int nb_items;
     int selected_item;
     int start_item; /* the item that is displayed at the top of the screen */
 
-    void (*callback_get_item_icon)(int selected_item, ICON * icon);
-    char * (*callback_get_item_name)(int selected_item, char *buffer);
+    void (*callback_get_item_icon)
+        (int selected_item, void * data, ICON * icon);
+    char * (*callback_get_item_name)
+        (int selected_item, void * data, char *buffer);
 
     struct screen * display;
     int line_scroll_limit;
     /* defines wether the list should stop when reaching the top/bottom
      * or should continue (by going to bottom/top) */
     bool limit_scroll;
+    /* The data that will be passed to the callback function YOU implement */
+    void * data;
 };
 
 /*
@@ -89,9 +118,12 @@ struct gui_list
  *    to a given item number
  */
 extern void gui_list_init(struct gui_list * gui_list,
-            void (*callback_get_item_icon)(int selected_item, ICON * icon),
-            char * (*callback_get_item_name)(int selected_item, char *buffer)
-            );
+    void (*callback_get_item_icon)
+        (int selected_item, void * data, ICON * icon),
+    char * (*callback_get_item_name)
+        (int selected_item, void * data, char *buffer),
+    void * data
+    );
 
 /*
  * Sets the numbers of items the list can currently display
@@ -99,7 +131,8 @@ extern void gui_list_init(struct gui_list * gui_list,
  *  - gui_list : the list structure to initialize
  *  - nb_items : the numbers of items you want
  */
-extern inline void gui_list_set_nb_items(struct gui_list * gui_list, int nb_items);
+#define gui_list_set_nb_items(gui_list, nb) \
+    (gui_list)->nb_items = nb
 
 /*
  * Puts the selection in the screen
@@ -125,7 +158,8 @@ extern void gui_list_set_display(struct gui_list * gui_list,
  *  - gui_list : the list structure
  * Returns the position
  */
-extern inline int gui_list_get_sel_pos(struct gui_list * gui_list);
+#define gui_list_get_sel_pos(gui_list) \
+    (gui_list)->selected_item
 
 /*
  * Selects an item in the list
@@ -190,7 +224,8 @@ extern void gui_list_del_item(struct gui_list * gui_list);
  *    - true : stops when reaching top/bottom
  *    - false : continues to go to bottom/top when reaching top/bottom
  */
-extern inline void gui_list_limit_scroll(struct gui_list * gui_list, bool scroll);
+#define gui_list_limit_scroll(gui_list, scroll) \
+    (gui_list)->limit_scroll=scroll
 
 /*
  * This part handles as many lists as there are connected screens
@@ -206,13 +241,21 @@ struct gui_synclist
     struct gui_list gui_list[NB_SCREENS];
 };
 
-extern void gui_synclist_init(struct gui_synclist * lists,
-             void (*callback_get_item_icon)(int selected_item, ICON * icon),
-             char * (*callback_get_item_name)(int selected_item, char *buffer)
-             );
+extern void gui_synclist_init(
+    struct gui_synclist * lists,
+    void (*callback_get_item_icon)
+        (int selected_item, void * data, ICON * icon),
+    char * (*callback_get_item_name)
+        (int selected_item, void * data, char *buffer),
+    void * data
+    );
 extern void gui_synclist_set_nb_items(struct gui_synclist * lists, int nb_items);
 
 extern int  gui_synclist_get_sel_pos(struct gui_synclist * lists);
+
+#define gui_synclist_get_sel_pos(lists) \
+    gui_list_get_sel_pos(&((lists)->gui_list[0]))
+
 extern void gui_synclist_draw(struct gui_synclist * lists);
 extern void gui_synclist_select_item(struct gui_synclist * lists,
                                      int item_number);
diff --git a/apps/gui/statusbar.c b/apps/gui/statusbar.c
index 0e7210218e..0f24208d33 100644
--- a/apps/gui/statusbar.c
+++ b/apps/gui/statusbar.c
@@ -40,9 +40,7 @@
 
 /* FIXME: should be removed from icon.h to avoid redefinition,
    but still needed for compatibility with old system */
-#define STATUSBAR_X_POS                         0
-#define STATUSBAR_Y_POS                         0 /* MUST be a multiple of 8 */
-#define STATUSBAR_HEIGHT                        8
+
 #define STATUSBAR_BATTERY_X_POS                 0
 #define STATUSBAR_BATTERY_WIDTH                 18
 #define STATUSBAR_PLUG_X_POS                    STATUSBAR_X_POS + \
@@ -115,7 +113,7 @@ void gui_statusbar_draw(struct gui_statusbar * bar, bool force_redraw)
     struct tm* tm; /* For Time */
 #endif
 
-#ifndef HAVE_LCD_BITMAP
+#ifdef HAVE_LCD_CHARCELLS
     (void)force_redraw; /* players always "redraw" */
 #endif
 
@@ -259,7 +257,7 @@ void gui_statusbar_draw(struct gui_statusbar * bar, bool force_redraw)
     }
 
 
-#ifndef HAVE_LCD_BITMAP
+#ifdef HAVE_LCD_CHARCELLS
     if (bar->info.battlevel > -1)
         display->icon(ICON_BATTERY, battery_state);
     display->icon(ICON_BATTERY_1, bar->info.battlevel > 25);
diff --git a/apps/gui/statusbar.h b/apps/gui/statusbar.h
index d3acbec8e5..d80968ff5e 100644
--- a/apps/gui/statusbar.h
+++ b/apps/gui/statusbar.h
@@ -23,6 +23,10 @@
 #include "config.h"
 #include "status.h"
 
+#define STATUSBAR_X_POS                         0
+#define STATUSBAR_Y_POS                         0 /* MUST be a multiple of 8 */
+#define STATUSBAR_HEIGHT                        8
+
 struct status_info {
     int battlevel;
     int volume;
diff --git a/apps/screen_access.c b/apps/screen_access.c
index e56a75dcce..8656ee8ace 100644
--- a/apps/screen_access.c
+++ b/apps/screen_access.c
@@ -171,24 +171,6 @@ void screen_update_nblines(struct screen * screen)
 
 }
 
-#ifdef HAVE_LCD_BITMAP
-int screen_get_text_y_start(struct screen * screen)
-{
-    screen=0;/* Avoid warning, this parameter is here for api integrity */
-    return(global_settings.statusbar?STATUSBAR_HEIGHT:0);
-}
-
-int screen_get_text_y_end(struct screen * screen)
-{
-#ifdef HAS_BUTTONBAR
-    return( screen->height - (global_settings.buttonbar?BUTTONBAR_HEIGHT:0) );
-#else
-    return( screen->height );
-#endif
-
-}
-#endif
-
 void screen_access_init(void)
 {
     screen_init(&screens[0], SCREEN_MAIN);
diff --git a/apps/screen_access.h b/apps/screen_access.h
index b04cabff46..2113a38757 100644
--- a/apps/screen_access.h
+++ b/apps/screen_access.h
@@ -7,7 +7,7 @@
  *                     \/            \/     \/    \/            \/
  * $Id$
  *
- * Copyright (C) 2005 by Kévin FERRARE
+ * Copyright (C) 2005 by K�in FERRARE
  *
  * All files in this archive are subject to the GNU General Public License.
  * See the file COPYING in the source tree root for full license agreement.
@@ -34,7 +34,7 @@ enum screen_type {
 #define NB_SCREENS 1
 #endif
 
-#ifndef HAVE_LCD_BITMAP
+#ifdef HAVE_LCD_CHARCELLS
 #define MAX_LINES_ON_SCREEN 2
 #endif
 
@@ -113,15 +113,23 @@ extern void screen_update_nblines(struct screen * screen);
  * - screen : the screen structure
  * Returns the number of pixels
  */
-extern int screen_get_text_y_start(struct screen * screen);
+#define screen_get_text_y_start(screen) \
+    (global_settings.statusbar?STATUSBAR_HEIGHT:0)
 
 /*
  * Compute the number of pixels below which text can't be displayed
  * - screen : the screen structure
  * Returns the number of pixels
  */
-extern int screen_get_text_y_end(struct screen * screen);
-#endif
+#ifdef HAS_BUTTONBAR
+#define screen_get_text_y_end(screen) \
+    ( (screen)->height - (global_settings.buttonbar?BUTTONBAR_HEIGHT:0) )
+#else
+#define screen_get_text_y_end(screen) \
+    ( (screen)->height )
+#endif /* HAS_BUTTONBAR */
+
+#endif /* HAVE_LCD_BITMAP */
 
 /*
  * Initializes the whole screen_access api
diff --git a/apps/tree.c b/apps/tree.c
index 33fb92259c..738b9fcf11 100644
--- a/apps/tree.c
+++ b/apps/tree.c
@@ -146,16 +146,18 @@ char * strip_extension(char * filename, char * buffer)
     else
         return(filename);
 }
-char * tree_get_filename(int selected_item, char *buffer)
+char * tree_get_filename(int selected_item, void * data, char *buffer)
 {
+    struct tree_context * local_tc=(struct tree_context *)data;
     char *name;
     int attr=0;
-    bool id3db = *tc.dirfilter == SHOW_ID3DB;
+    bool id3db = *(local_tc->dirfilter) == SHOW_ID3DB;
+
     if (id3db) {
-        name = ((char**)tc.dircache)[selected_item * tc.dentry_size];
+        name = ((char**)local_tc->dircache)[selected_item * local_tc->dentry_size];
     }
     else {
-        struct entry* dc = tc.dircache;
+        struct entry* dc = local_tc->dircache;
         struct entry* e = &dc[selected_item];
         name = e->name;
         attr = e->attr;
@@ -163,8 +165,8 @@ char * tree_get_filename(int selected_item, char *buffer)
     /* if any file filter is on, and if it's not a directory,
      * strip the extension */
 
-    if ( (*tc.dirfilter != SHOW_ID3DB) && !(attr & ATTR_DIRECTORY)
-        && (*tc.dirfilter != SHOW_ALL) )
+    if ( (*(local_tc->dirfilter) != SHOW_ID3DB) && !(attr & ATTR_DIRECTORY)
+        && (*(local_tc->dirfilter) != SHOW_ALL) )
     {
         return(strip_extension(name, buffer));
     }
@@ -172,14 +174,15 @@ char * tree_get_filename(int selected_item, char *buffer)
 }
 
 
-void tree_get_fileicon(int selected_item, ICON * icon)
+void tree_get_fileicon(int selected_item, void * data, ICON * icon)
 {
-    bool id3db = *tc.dirfilter == SHOW_ID3DB;
+    struct tree_context * local_tc=(struct tree_context *)data;
+    bool id3db = *(local_tc->dirfilter) == SHOW_ID3DB;
     if (id3db) {
         *icon = db_get_icon(&tc);
     }
     else {
-        struct entry* dc = tc.dircache;
+        struct entry* dc = local_tc->dircache;
         struct entry* e = &dc[selected_item];
         *icon = filetype_get_icon(e->attr);
     }
@@ -224,7 +227,7 @@ void browse_root(void)
     gui_buttonbar_set_display(&tree_buttonbar, &(screens[SCREEN_MAIN]) );
 #endif
     gui_syncstatusbar_init(&statusbars);
-    gui_synclist_init(&tree_lists, &tree_get_fileicon, &tree_get_filename);
+    gui_synclist_init(&tree_lists, &tree_get_fileicon, &tree_get_filename, &tc);
 #ifndef SIMULATOR
     dirbrowse();
 #else