touch devices: Disable touch on softlock.

Target that have a touchpad/touchscreen should disable it while
being locked (In order to avoid LCD to drain battery power due to
"key locked" constant reporting messages. If they a have a keylock
button this was already handled at driver level. If not (e.g. fuze+),
they will have to implement a switch at driver level that action.c
can operate on softlock.
This patch does the following for any target having a touchpad
or a touchscreen and no HAS_BUTTON_HOLD (ie any softlock target)
1) it implements the code to call button_enable_touch(bool en) in
action.c.
2) button_enable_touch is implemented in button.c and call
either touchpad_enable or touchscreen_enable
3) those two function are implemented respectively in touchscreen.c
and a new touchpad.c file. They provide a generic way to silents touch's
device and call a function at driver level where target specific code
can be implemented if possible/needed (for power saving for instance).
Those function name are touchpad_enable_device and touchscreen_enable_device
4) we implement an empty function at driver level of targets that need it
to have them still being able to compiled.

Change-Id: I9ead78a25bd33466a8533f5b9f259b395cb5ce49
Reviewed-on: http://gerrit.rockbox.org/569
Reviewed-by: Thomas Martitz <kugel@rockbox.org>
Reviewed-by: Amaury Pouly <amaury.pouly@gmail.com>

1 files changed, 15 insertions, 1 deletions

diff --git a/apps/action.c b/apps/action.c
index 2492a7d08e..25f559f7bd 100644
--- a/apps/action.c
+++ b/apps/action.c
@@ -294,6 +294,10 @@ static int get_action_worker(int context, int timeout,
         {
             last_button = BUTTON_NONE;
             keys_locked = false;
+#if defined(HAVE_TOUCHPAD) || defined(HAVE_TOUCHSCREEN)
+            /* enable back touch device */
+            button_enable_touch(true);
+#endif
             splash(HZ/2, str(LANG_KEYLOCK_OFF));
             return ACTION_REDRAW;
         }
@@ -307,6 +311,13 @@ static int get_action_worker(int context, int timeout,
             return ACTION_REDRAW;
         }
     }
+#if defined(HAVE_TOUCHPAD) || defined(HAVE_TOUCHSCREEN)
+    else
+    {
+        /* make sure touchpad get reactivated if we quit the screen */
+        button_enable_touch(true);
+    }
+#endif
     context &= ~ALLOW_SOFTLOCK;
 #endif /* HAS_BUTTON_HOLD */
 
@@ -373,7 +384,10 @@ static int get_action_worker(int context, int timeout,
         unlock_combo = button;
         keys_locked = true;
         splash(HZ/2, str(LANG_KEYLOCK_ON));
-
+ #if defined(HAVE_TOUCHPAD) || defined(HAVE_TOUCHSCREEN)
+        /* disable touch device on keylock */
+        button_enable_touch(false);
+ #endif
         button_clear_queue();
         return ACTION_REDRAW;
     }