123 lines
4.1 KiB
C
123 lines
4.1 KiB
C
|
/***************************************************************************
|
||
|
|
* __________ __ ___.
|
||
|
|
* 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.
|
||
|
|
*
|
||
|
|
****************************************************************************/
|
||
|
|
#include "button-lradc-imx233.h"
|
||
|
|
#include "stdlib.h"
|
||
|
|
#include "lradc-imx233.h"
|
||
|
|
|
||
|
|
#ifndef IMX233_BUTTON_LRADC_CHANNEL
|
||
|
|
#error You must define IMX233_BUTTON_LRADC_CHANNEL to use button-lradc
|
||
|
|
#endif
|
||
|
|
|
||
|
|
/* physical channel */
|
||
|
|
#define CHAN IMX233_BUTTON_LRADC_CHANNEL
|
||
|
|
/* number of irq per second */
|
||
|
|
#ifdef IMX233_BUTTON_LRADC_RATE
|
||
|
|
# define RATE IMX233_BUTTON_LRADC_RATE
|
||
|
|
#else
|
||
|
|
# define RATE HZ
|
||
|
|
#endif
|
||
|
|
/* number of samples per irq */
|
||
|
|
#ifdef IMX233_BUTTON_LRADC_SAMPLES
|
||
|
|
# define SAMPLES IMX233_BUTTON_LRADC_SAMPLES
|
||
|
|
#else
|
||
|
|
# define SAMPLES 10
|
||
|
|
#endif
|
||
|
|
/* delay's delay */
|
||
|
|
#define DELAY (LRADC_DELAY_FREQ / RATE / SAMPLES)
|
||
|
|
|
||
|
|
static int button_delay;
|
||
|
|
static int button_chan;
|
||
|
|
static int button_val[2];
|
||
|
|
static int button_idx;
|
||
|
|
static int button_mask;
|
||
|
|
static int table_size;
|
||
|
|
|
||
|
|
static int button_find(int val)
|
||
|
|
{
|
||
|
|
// shortcuts
|
||
|
|
struct imx233_button_lradc_mapping_t *table = imx233_button_lradc_mapping;
|
||
|
|
/* FIXME use a dichotomy */
|
||
|
|
int i = 0;
|
||
|
|
while(i < table_size && val >= table[i].adc_val)
|
||
|
|
i++;
|
||
|
|
// extreme cases
|
||
|
|
int btn = 0;
|
||
|
|
// if i=n then choose i-1 and otherwise choose best between i-1 and i
|
||
|
|
if(i == 0)
|
||
|
|
btn = table[0].btn;
|
||
|
|
else if(i == table_size)
|
||
|
|
btn = table[i - 1].btn;
|
||
|
|
// choose best between i-1 and i (note that table[i-1]<=val<=table[i]) */
|
||
|
|
else if(val - table[i - 1].adc_val < table[i].adc_val - val)
|
||
|
|
btn = table[i - 1].btn;
|
||
|
|
else
|
||
|
|
btn = table[i].btn;
|
||
|
|
return btn;
|
||
|
|
}
|
||
|
|
|
||
|
|
int button_value;
|
||
|
|
|
||
|
|
static void button_lradc_irq(int chan)
|
||
|
|
{
|
||
|
|
(void) chan;
|
||
|
|
/* read value, kick channel */
|
||
|
|
button_val[button_idx] = imx233_lradc_read_channel(button_chan) / SAMPLES;
|
||
|
|
imx233_lradc_clear_channel(button_chan);
|
||
|
|
imx233_lradc_setup_channel(button_chan, true, true, SAMPLES - 1, LRADC_SRC(CHAN));
|
||
|
|
imx233_lradc_setup_delay(button_delay, 1 << button_chan, 0, SAMPLES - 1, DELAY);
|
||
|
|
imx233_lradc_kick_delay(button_delay);
|
||
|
|
button_value = button_val[button_idx];
|
||
|
|
/* compute mask, compare to previous one */
|
||
|
|
button_val[button_idx] = button_find(button_val[button_idx]);
|
||
|
|
button_idx = 1 - button_idx;
|
||
|
|
if(button_val[0] == button_val[1])
|
||
|
|
button_mask = button_val[0];
|
||
|
|
}
|
||
|
|
|
||
|
|
void imx233_button_lradc_init(void)
|
||
|
|
{
|
||
|
|
button_chan = imx233_lradc_acquire_channel(LRADC_SRC(CHAN), TIMEOUT_NOBLOCK);
|
||
|
|
if(button_chan < 0)
|
||
|
|
panicf("Cannot get channel for button-lradc");
|
||
|
|
button_delay = imx233_lradc_acquire_delay(TIMEOUT_NOBLOCK);
|
||
|
|
if(button_delay < 0)
|
||
|
|
panicf("Cannot get delay for button-lradc");
|
||
|
|
imx233_lradc_setup_channel(button_chan, true, true, SAMPLES - 1, LRADC_SRC(CHAN));
|
||
|
|
imx233_lradc_setup_delay(button_delay, 1 << button_chan, 0, SAMPLES - 1, DELAY);
|
||
|
|
imx233_lradc_enable_channel_irq(button_chan, true);
|
||
|
|
imx233_lradc_set_channel_irq_callback(button_chan, button_lradc_irq);
|
||
|
|
imx233_lradc_kick_delay(button_delay);
|
||
|
|
|
||
|
|
table_size = 0;
|
||
|
|
while(imx233_button_lradc_mapping[table_size].btn != IMX233_BUTTON_LRADC_END)
|
||
|
|
table_size++;
|
||
|
|
}
|
||
|
|
|
||
|
|
bool imx233_button_lradc_hold(void)
|
||
|
|
{
|
||
|
|
return button_mask == IMX233_BUTTON_LRADC_HOLD;
|
||
|
|
}
|
||
|
|
|
||
|
|
int imx233_button_lradc_read(void)
|
||
|
|
{
|
||
|
|
return button_mask == IMX233_BUTTON_LRADC_HOLD ? 0 : button_mask;
|
||
|
|
}
|