Fuze+: add a configurable deadzone area for touchpad buttons

To stop erroneous button presses, allow users to add a deadzone between
the button via the Settings > General > System menu > Touch Dead Zone.

The configuration was chosen this way: the touchpad has the same DPI
in both direction so the setting applies the same on both the X and Y
axis. The setting ranges from 0 to 100 and is internally multiplied by 2
giving a maximum deadzone of 2*100 = 200 around each button, which
account for 400 total (once around each button), effectively reducing
each virtual button from 1000x600 to 600x200 when using the maximum value.

Change-Id: I8683c63d2950200eb32d1dda0a00bbd92d83d5be
Reviewed-on: http://gerrit.rockbox.org/677
Reviewed-by: Benjamin Brown <foolshperson@gmail.com>
Tested: Benjamin Brown <foolshperson@gmail.com>
Reviewed-by: Amaury Pouly <amaury.pouly@gmail.com>

apps/features.txt

@@ -199,6 +199,10 @@ lineout_poweroff
 touchscreen
 #endif
 
+#if defined(HAVE_TOUCHPAD_DEADZONE)
+touchpad_deadzone
+#endif
+
 #if defined(HAVE_IMX233_CODEC) || defined(HAVE_WM8750) || defined(HAVE_WM8978)
 depth_3d
 #endif

apps/lang/english-us.lang

@@ -10605,6 +10605,23 @@
     gigabeatfx,sansafuzeplus: "Touchpad Sensitivity"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_DEADZONE
+  desc: touchpad deadzone setting
+  user: core
+  <source>
+    *: none
+    sansafuzeplus: "Touchpad Dead Zone"
+  </source>
+  <dest>
+    *: none
+    sansafuzeplus: "Touchpad Dead Zone"
+  </dest>
+  <voice>
+    *: none
+    sansafuzeplus: "Touchpad Dead Zone"
+  </voice>
+</phrase>
 <phrase>
   id: LANG_HIGH
   desc: in settings_menu

apps/lang/english.lang

@@ -10692,6 +10692,23 @@
     gigabeatfx,sansafuzeplus: "Touchpad Sensitivity"
   </voice>
 </phrase>
+<phrase>
+  id: LANG_DEADZONE
+  desc: touchpad deadzone setting
+  user: core
+  <source>
+    *: none
+    sansafuzeplus: "Touchpad Dead Zone"
+  </source>
+  <dest>
+    *: none
+    sansafuzeplus: "Touchpad Dead Zone"
+  </dest>
+  <voice>
+    *: none
+    sansafuzeplus: "Touchpad Dead Zone"
+  </voice>
+</phrase>
 <phrase>
   id: LANG_HIGH
   desc: in settings_menu

apps/menus/settings_menu.c

@@ -317,6 +317,10 @@ MENUITEM_SETTING(buttonlight_brightness, &global_settings.buttonlight_brightness
 MENUITEM_SETTING(touchpad_sensitivity, &global_settings.touchpad_sensitivity, NULL);
 #endif
 
+#ifdef HAVE_TOUCHPAD_DEADZONE
+MENUITEM_SETTING(touchpad_deadzone, &global_settings.touchpad_deadzone, NULL);
+#endif
+
 #ifdef HAVE_QUICKSCREEN
 MENUITEM_SETTING(shortcuts_replaces_quickscreen, &global_settings.shortcuts_replaces_qs, NULL);
 #endif
@@ -363,6 +367,9 @@ MAKE_MENU(system_menu, ID2P(LANG_SYSTEM),
 #ifdef HAVE_TOUCHPAD_SENSITIVITY_SETTING
             &touchpad_sensitivity,
 #endif
+#ifdef HAVE_TOUCHPAD_DEADZONE
+            &touchpad_deadzone,
+#endif
 #ifdef USB_ENABLE_HID
             &usb_hid,
             &usb_keypad_mode,

apps/settings.c

@@ -1061,6 +1061,10 @@ void settings_apply(bool read_disk)
     touchpad_set_sensitivity(global_settings.touchpad_sensitivity);
 #endif
 
+#ifdef HAVE_TOUCHPAD_DEADZONE
+    touchpad_set_deadzone(global_settings.touchpad_deadzone);
+#endif
+
 #ifdef HAVE_USB_CHARGING_ENABLE
     usb_charging_enable(global_settings.usb_charging);
 #endif

apps/settings.h

@@ -460,6 +460,10 @@ struct user_settings
     int touchpad_sensitivity;
 #endif
 
+#ifdef HAVE_TOUCHPAD_DEADZONE
+    int touchpad_deadzone;
+#endif
+
     int  pause_rewind; /* time in s to rewind when pausing */
 #ifdef HAVE_HEADPHONE_DETECTION
     int  unplug_mode; /* pause on headphone unplug */

apps/settings_list.c

@@ -2024,6 +2024,14 @@ const struct settings_list settings[] = {
                    ID2P(LANG_NORMAL), ID2P(LANG_HIGH)),
 #endif /* boolean or analogig values */
 #endif /* HAVE_TOUCHPAD_SENSITIVITY_SETTING */
+
+#ifdef HAVE_TOUCHPAD_DEADZONE
+    INT_SETTING(F_NO_WRAP, touchpad_deadzone, LANG_DEADZONE,
+                DEFAULT_TOUCHPAD_DEADZONE_SETTING, "touchpad deadzone", UNIT_INT,
+                MIN_TOUCHPAD_DEADSPACE_SETTING, MAX_TOUCHPAD_DEADSPACE_SETTING, 1,
+                NULL, NULL, touchpad_set_deadzone),
+#endif
+
 #ifdef HAVE_QUICKSCREEN
    CUSTOM_SETTING(0, qs_items[QUICKSCREEN_TOP], LANG_TOP_QS_ITEM,
                   NULL, "qs top",

firmware/export/config/sansafuzeplus.h

@@ -80,6 +80,14 @@
 #define MAX_TOUCHPAD_SENSITIVITY_SETTING        25
 #define DEFAULT_TOUCHPAD_SENSITIVITY_SETTING    13
 
+/* Define this to enable dead zone on touchpad */
+#ifndef SIMULATOR
+#define HAVE_TOUCHPAD_DEADZONE
+#define DEFAULT_TOUCHPAD_DEADZONE_SETTING    30
+#define MIN_TOUCHPAD_DEADSPACE_SETTING       0
+#define MAX_TOUCHPAD_DEADSPACE_SETTING       100
+#endif
+
 /* Define this to enable morse code input */
 #define HAVE_MORSE_INPUT
 

firmware/target/arm/imx233/sansa-fuzeplus/button-fuzeplus.c

@@ -192,26 +192,12 @@ bool button_debug_screen(void)
     return true;
 }
 
-struct button_area_t
+/* we emulate a 3x3 grid, this gives the button mapping */
+int button_mapping[3][3] =
 {
-    /* define a rectangle region */
+    {BUTTON_BOTTOMLEFT, BUTTON_LEFT, BUTTON_BACK},
-    int lx, ly;
+    {BUTTON_DOWN, BUTTON_SELECT, BUTTON_UP},
-    int rx, ry;
+    {BUTTON_BOTTOMRIGHT, BUTTON_RIGHT, BUTTON_PLAYPAUSE},
-    int button;
-};
-
-static struct button_area_t button_areas[] =
-{
-    {1003, 658, 2006, 1316, BUTTON_SELECT},
-    {0, 658, 1003, 1316, BUTTON_LEFT},
-    {2006, 658, 3009, 1316, BUTTON_RIGHT},
-    {1003, 0 , 2006, 658, BUTTON_DOWN},
-    {1003, 1316, 2006, 1974, BUTTON_UP},
-    {2006, 1316, 3009, 1974, BUTTON_PLAYPAUSE},
-    {0, 1316, 1003, 1974, BUTTON_BACK},
-    {0, 0 , 1003, 658, BUTTON_BOTTOMLEFT},
-    {2006, 0 , 3009, 658, BUTTON_BOTTOMRIGHT},
-    {0, 0, 0, 0, 0},
 };
 
 #define RMI_INTERRUPT       1
@@ -219,6 +205,9 @@ static struct button_area_t button_areas[] =
 #define RMI_SET_SLEEP_MODE  3
 /* timeout before lowering touchpad power from lack of activity */
 #define ACTIVITY_TMO        (5 * HZ)
+#define TOUCHPAD_WIDTH      3010
+#define TOUCHPAD_HEIGHT     1975
+#define DEADZONE_MULTIPLIER 2 /* deadzone multiplier */
 
 static int touchpad_btns = 0;
 static long rmi_stack [DEFAULT_STACK_SIZE/sizeof(long)];
@@ -226,17 +215,38 @@ static const char rmi_thread_name[] = "rmi";
 static struct event_queue rmi_queue;
 static unsigned last_activity = 0;
 static bool t_enable = true;
+static int deadzone;
+
+/* Ignore deadzone function. If outside of the pad, project to border. */
+static int find_button_no_deadzone(int x, int y)
+{
+    /* compute grid coordinate */
+    int gx = MAX(MIN(x * 3 / TOUCHPAD_WIDTH, 2), 0);
+    int gy = MAX(MIN(y * 3 / TOUCHPAD_HEIGHT, 2), 0);
+
+    return button_mapping[gx][gy];
+}
 
 static int find_button(int x, int y)
 {
-    struct button_area_t *area = button_areas;
+    /* find button ignoring deadzones */
-    for(; area->button != 0; area++)
+    int btn = find_button_no_deadzone(x, y);
-    {
+    /* To check if we are in a deadzone, we try to shift the coordinates
-        if(area->lx <= x && x <= area->rx &&
+     * and see if we get the same button. Not that we do not want to apply
-                area->ly <= y && y <= area->ry)
+     * the deadzone in the borders ! The code works even in the borders because
-            return area->button;
+     * the find_button_no_deadzone() project out-of-bound coordinates to the
-    }
+     * borders */
+    if(find_button_no_deadzone(x + deadzone, y) != btn ||
+            find_button_no_deadzone(x - deadzone, y) != btn ||
+            find_button_no_deadzone(x, y + deadzone) != btn ||
+            find_button_no_deadzone(x, y - deadzone) != btn)
         return 0;
+    return btn;
+}
+
+void touchpad_set_deadzone(int touchpad_deadzone)
+{
+    deadzone = touchpad_deadzone * DEADZONE_MULTIPLIER;
 }
 
 static int touchpad_read_device(void)

firmware/target/arm/imx233/sansa-fuzeplus/button-target.h

@@ -24,6 +24,7 @@
 #include <stdbool.h>
 bool button_debug_screen(void);
 void touchpad_set_sensitivity(int level);
+void touchpad_set_deadzone(int touchpad_deadzone);
 void touchpad_enable_device(bool en);
 
 /* Main unit's buttons */