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Diffstat (limited to 'firmware/target/arm/imx233/button-lradc-imx233.h')
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diff --git a/firmware/target/arm/imx233/button-lradc-imx233.h b/firmware/target/arm/imx233/button-lradc-imx233.h
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+/***************************************************************************
+ * __________ __ ___.
+ * Open \______ \ ____ ____ | | _\_ |__ _______ ___
+ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
+ * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
+ * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
+ * \/ \/ \/ \/ \/
+ * $Id$
+ *
+ * Copyright (C) 2013 by Amaury Pouly
+ *
+ * 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.
+ *
+ ****************************************************************************/
+#ifndef __button_lradc_imx233__
+#define __button_lradc_imx233__
+
+#include "button.h"
+#include "button-target.h"
+
+/** This driver implements button sensing with lradc. It does debouncing
+ * and can handle hold sensing too. It can be tweaked using the following defines
+ * and variables:
+ * - imx233_button_lradc_mapping: target-defined table of adc values and mapping
+ * - IMX233_BUTTON_LRADC_CHANNEL: lradc channel to use
+ */
+
+/* special value for btn to handle HOLD */
+#define IMX233_BUTTON_LRADC_END -1
+#define IMX233_BUTTON_LRADC_HOLD -2
+
+struct imx233_button_lradc_mapping_t
+{
+ int adc_val;
+ int btn;
+};
+
+/* target-defined
+ * NOTE for proper operation, the table should contain entries for all states, including:
+ * - one with adc_val set to default value when no button is pressed
+ * - one with adc_val set to value when hold is selected (if hold is sensed using adc)
+ * - a dummy entry with btn set to IMX233_BUTTON_LRADC_END as the last entry
+ * The table must be sorted by increasing values of adc_val */
+extern struct imx233_button_lradc_mapping_t imx233_button_lradc_mapping[];
+
+void imx233_button_lradc_init(void);
+int imx233_button_lradc_read(void);
+bool imx233_button_lradc_hold(void);
+
+#endif /* __button_lradc_imx233__ */