boards/arm/stm32/nucleo-f303re/src/stm32_buttons.c

/****************************************************************************
 * boards/arm/stm32/nucleo-f303re/src/stm32_buttons.c
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.  The
 * ASF licenses this file to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the
 * License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations
 * under the License.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <stdint.h>
#include <stdbool.h>
#include <errno.h>

#include <nuttx/board.h>
#include <arch/board/board.h>

#include "stm32.h"
#include "nucleo-f303re.h"

#ifdef CONFIG_ARCH_BUTTONS

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Name: board_button_initialize
 *
 * Description:
 *   board_button_initialize() must be called to initialize button
 *   resources.  After that, board_buttons() may be called to collect the
 *   current state of all buttons or board_button_irq() may be called to
 *   register button interrupt handlers.
 *
 ****************************************************************************/

uint32_t board_button_initialize(void)
{
  /* Configure the single button as an input.  NOTE that EXTI interrupts are
   * also configured for the pin.
   */

  stm32_configgpio(GPIO_BTN_USER);
  return NUM_BUTTONS;
}

/****************************************************************************
 * Name: board_buttons
 *
 * Description:
 *   After board_button_initialize() has been called, board_buttons() may be
 *   called to collect the state of all buttons.  board_buttons() returns an
 *   32-bit unsigned integer with each bit associated with a button.  See the
 *   BUTTON_*_BIT definitions in board.h for the meaning of each bit.
 *
 ****************************************************************************/

uint32_t board_buttons(void)
{
  /* Check the state of the USER button.  A LOW value means that the key is
   * pressed.
   */

  return stm32_gpioread(GPIO_BTN_USER) ? 0 : BUTTON_USER_BIT;
}

/****************************************************************************
 * Name: board_button_irq
 *
 * Description:
 *   board_button_irq() may be called to register an interrupt handler that
 *   will be called when a button is depressed or released.  The ID value is
 *   a button enumeration value that uniquely identifies a button resource.
 *   See the BUTTON_* definitions in board.h for the meaning of the
 *   enumeration value.
 *
 ****************************************************************************/

#ifdef CONFIG_ARCH_IRQBUTTONS
int board_button_irq(int id, xcpt_t irqhandler, void *arg)
{
  int ret = -EINVAL;

  if (id == BUTTON_USER)
    {
      ret = stm32_gpiosetevent(GPIO_BTN_USER, true, true, true, irqhandler,
                               arg);
    }

  return ret;
}
#endif

#endif /* CONFIG_ARCH_BUTTONS */