nes-proj/os/dev/button-hal.c
2018-08-31 11:06:32 +02:00

232 lines
8.1 KiB
C

/*
* Copyright (c) 2017, George Oikonomou - http://www.spd.gr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*---------------------------------------------------------------------------*/
/**
* \addtogroup button_hal
* @{
*
* \file
* Platform-independent button driver.
*/
/*---------------------------------------------------------------------------*/
#include "contiki.h"
#include "sys/process.h"
#include "sys/ctimer.h"
#include "sys/critical.h"
#include "dev/gpio-hal.h"
#include "dev/button-hal.h"
#include <stdint.h>
#include <stdbool.h>
#include <string.h>
/*---------------------------------------------------------------------------*/
PROCESS(button_hal_process, "Button HAL process");
/*---------------------------------------------------------------------------*/
process_event_t button_hal_press_event;
process_event_t button_hal_release_event;
process_event_t button_hal_periodic_event;
/*---------------------------------------------------------------------------*/
/* A mask of all pins that have changed state since the last process poll */
static volatile gpio_hal_pin_mask_t pmask;
/*---------------------------------------------------------------------------*/
extern button_hal_button_t *button_hal_buttons[];
/*---------------------------------------------------------------------------*/
/* Common handler for all handler events, and register it with the GPIO HAL */
static gpio_hal_event_handler_t button_event_handler;
/*---------------------------------------------------------------------------*/
static void
duration_exceeded_callback(void *btn)
{
button_hal_button_t *button = (button_hal_button_t *)btn;
button->press_duration_seconds++;
ctimer_set(&button->duration_ctimer, CLOCK_SECOND,
duration_exceeded_callback, button);
process_post(PROCESS_BROADCAST, button_hal_periodic_event, button);
}
/*---------------------------------------------------------------------------*/
static void
debounce_handler(void *btn)
{
button_hal_button_t *button;
int expired;
uint8_t button_state;
button = (button_hal_button_t *)btn;
/*
* A new debounce may have been triggered after expiration of the previous
* one but before we got called.
*/
if(!ctimer_expired(&button->debounce_ctimer)) {
return;
}
expired = ctimer_expired(&button->duration_ctimer);
button_state = button_hal_get_state(button);
/*
* A debounce timer expired. Inspect the button's state. If the button's
* state is the same as it was before, then we ignore this as noise.
*/
if(button_state == BUTTON_HAL_STATE_PRESSED && expired) {
/*
* Button is pressed and no tick counter running. Treat as new press.
* Include the debounce duration in the first periodic, so that the
* callback will happen 1 second after the button press, not 1 second
* after the end of the debounce. Notify process about the press event.
*/
button->press_duration_seconds = 0;
ctimer_set(&button->duration_ctimer,
CLOCK_SECOND - BUTTON_HAL_DEBOUNCE_DURATION,
duration_exceeded_callback, button);
process_post(PROCESS_BROADCAST, button_hal_press_event, button);
} else if(button_state == BUTTON_HAL_STATE_RELEASED && expired == 0) {
/*
* Button is released and there is a duration_ctimer running. Treat this
* as a new release and notify processes.
*/
ctimer_stop(&button->duration_ctimer);
process_post(PROCESS_BROADCAST, button_hal_release_event, button);
}
}
/*---------------------------------------------------------------------------*/
static void
press_release_handler(gpio_hal_pin_mask_t pin_mask)
{
pmask |= pin_mask;
process_poll(&button_hal_process);
}
/*---------------------------------------------------------------------------*/
button_hal_button_t *
button_hal_get_by_id(uint8_t unique_id)
{
button_hal_button_t **button;
for(button = button_hal_buttons; *button != NULL; button++) {
if((*button)->unique_id == unique_id) {
return *button;
}
}
return NULL;
}
/*---------------------------------------------------------------------------*/
button_hal_button_t *
button_hal_get_by_index(uint8_t index)
{
if(index >= button_hal_button_count) {
return NULL;
}
return button_hal_buttons[index];
}
/*---------------------------------------------------------------------------*/
uint8_t
button_hal_get_state(button_hal_button_t *button)
{
uint8_t pin_state = gpio_hal_arch_read_pin(button->pin);
if((pin_state == 0 && button->negative_logic == true) ||
(pin_state == 1 && button->negative_logic == false)) {
return BUTTON_HAL_STATE_PRESSED;
}
return BUTTON_HAL_STATE_RELEASED;
}
/*---------------------------------------------------------------------------*/
void
button_hal_init()
{
button_hal_button_t **button;
gpio_hal_pin_cfg_t cfg;
button_hal_press_event = process_alloc_event();
button_hal_release_event = process_alloc_event();
button_hal_periodic_event = process_alloc_event();
button_event_handler.pin_mask = 0;
button_event_handler.handler = press_release_handler;
for(button = button_hal_buttons; *button != NULL; button++) {
cfg = GPIO_HAL_PIN_CFG_EDGE_BOTH | GPIO_HAL_PIN_CFG_INT_ENABLE |
(*button)->pull;
gpio_hal_arch_pin_set_input((*button)->pin);
gpio_hal_arch_pin_cfg_set((*button)->pin, cfg);
gpio_hal_arch_interrupt_enable((*button)->pin);
button_event_handler.pin_mask |= gpio_hal_pin_to_mask((*button)->pin);
}
process_start(&button_hal_process, NULL);
gpio_hal_register_handler(&button_event_handler);
}
/*---------------------------------------------------------------------------*/
PROCESS_THREAD(button_hal_process, ev, data)
{
int_master_status_t status;
gpio_hal_pin_mask_t pins;
button_hal_button_t **button;
PROCESS_BEGIN();
while(1) {
PROCESS_YIELD_UNTIL(ev == PROCESS_EVENT_POLL);
status = critical_enter();
pins = pmask;
pmask = 0;
critical_exit(status);
for(button = button_hal_buttons; *button != NULL; button++) {
if(gpio_hal_pin_to_mask((*button)->pin) & pins) {
/* Ignore all button presses/releases during its debounce */
if(ctimer_expired(&(*button)->debounce_ctimer)) {
/*
* Here we merely set a debounce timer. At the end of the debounce we
* will inspect the button's state and we will take action only if it
* has changed.
*
* This is to prevent erroneous edge detections due to interference.
*/
ctimer_set(&(*button)->debounce_ctimer, BUTTON_HAL_DEBOUNCE_DURATION,
debounce_handler, *button);
}
}
}
}
PROCESS_END();
}
/*---------------------------------------------------------------------------*/
/** @} */