| Amaury Pouly | 277d358 | 2013-06-18 16:43:27 +0200 | [diff] [blame^] | 1 | /*************************************************************************** |
| 2 | * __________ __ ___. |
| 3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ |
| 4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / |
| 5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < |
| 6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ |
| 7 | * \/ \/ \/ \/ \/ |
| 8 | * $Id$ |
| 9 | * |
| 10 | * Copyright (C) 2013 by Amaury Pouly |
| 11 | * |
| 12 | * This program is free software; you can redistribute it and/or |
| 13 | * modify it under the terms of the GNU General Public License |
| 14 | * as published by the Free Software Foundation; either version 2 |
| 15 | * of the License, or (at your option) any later version. |
| 16 | * |
| 17 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY |
| 18 | * KIND, either express or implied. |
| 19 | * |
| 20 | ****************************************************************************/ |
| 21 | #ifndef __button_lradc_imx233__ |
| 22 | #define __button_lradc_imx233__ |
| 23 | |
| 24 | #include "button.h" |
| 25 | #include "button-target.h" |
| 26 | |
| 27 | /** This driver implements button sensing with lradc. It does debouncing |
| 28 | * and can handle hold sensing too. It can be tweaked using the following defines |
| 29 | * and variables: |
| 30 | * - imx233_button_lradc_mapping: target-defined table of adc values and mapping |
| 31 | * - IMX233_BUTTON_LRADC_CHANNEL: lradc channel to use |
| 32 | */ |
| 33 | |
| 34 | /* special value for btn to handle HOLD */ |
| 35 | #define IMX233_BUTTON_LRADC_END -1 |
| 36 | #define IMX233_BUTTON_LRADC_HOLD -2 |
| 37 | |
| 38 | struct imx233_button_lradc_mapping_t |
| 39 | { |
| 40 | int adc_val; |
| 41 | int btn; |
| 42 | }; |
| 43 | |
| 44 | /* target-defined |
| 45 | * NOTE for proper operation, the table should contain entries for all states, including: |
| 46 | * - one with adc_val set to default value when no button is pressed |
| 47 | * - one with adc_val set to value when hold is selected (if hold is sensed using adc) |
| 48 | * - a dummy entry with btn set to IMX233_BUTTON_LRADC_END as the last entry |
| 49 | * The table must be sorted by increasing values of adc_val */ |
| 50 | extern struct imx233_button_lradc_mapping_t imx233_button_lradc_mapping[]; |
| 51 | |
| 52 | void imx233_button_lradc_init(void); |
| 53 | int imx233_button_lradc_read(void); |
| 54 | bool imx233_button_lradc_hold(void); |
| 55 | |
| 56 | #endif /* __button_lradc_imx233__ */ |