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-rw-r--r--firmware/backlight-sw-fading.c87
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diff --git a/firmware/backlight-sw-fading.c b/firmware/backlight-sw-fading.c
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+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (C) 2008 by Thomas Martitz
+ * Copyright (C) 2008 by Martin Ritter
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#include <stdbool.h>
+#include "backlight-target.h"
+#include "config.h"
+#include "system.h"
+#include "backlight.h"
+#include "backlight-sw-fading.h"
+
+/* To adapt a target do:
+ * - make sure _backlight_on doesn't set the brightness to something other than
+ * the previous value (lowest brightness in most cases)
+ * - #define USE_BACKLIGHT_SW_FADING in config-<target>.h
+ */
+
+/* can be MIN_BRIGHTNESS_SETTING-1 */
+static int current_brightness = DEFAULT_BRIGHTNESS_SETTING;
+
+void _backlight_fade_update_state(int brightness)
+{
+ current_brightness = brightness;
+}
+
+/* returns true if fade is finished */
+static bool _backlight_fade_up(void)
+{
+ if (LIKELY(current_brightness < backlight_brightness))
+ {
+ _backlight_set_brightness(++current_brightness);
+ }
+ return(current_brightness >= backlight_brightness);
+}
+
+/* returns true if fade is finished */
+static bool _backlight_fade_down(void)
+{
+ if (LIKELY(current_brightness > MIN_BRIGHTNESS_SETTING))
+ {
+ _backlight_set_brightness(--current_brightness);
+ return false;
+ }
+ else
+ {
+ /* decrement once more, since backlight is off */
+ current_brightness--;
+ _backlight_off();
+ return true;
+ }
+}
+
+bool _backlight_fade_step(int direction)
+{
+ bool done;
+ switch(direction)
+ {
+ case FADING_UP:
+ done = _backlight_fade_up();
+ break;
+ case FADING_DOWN:
+ done = _backlight_fade_down();
+ break;
+ default:
+ done = true;
+ break;
+ }
+ return(done);
+}