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/****************************************************************************
* configs/sam4s-xplained-pro/src/sam_buttons.c
*
* Copyright (C) 2014 Gregory Nutt. All rights reserved.
* Authors: Gregory Nutt <gnutt@nuttx.org>
* Bob Doiron
*
* 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 NuttX 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 OWNER 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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <stdint.h>
#include <nuttx/arch.h>
#include <nuttx/irq.h>
#include <arch/irq.h>
#include <arch/board/board.h>
#include "sam_gpio.h"
#include "sam4s-xplained-pro.h"
#ifdef CONFIG_ARCH_BUTTONS
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
static xcpt_t g_irqsw0;
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* 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.
*
****************************************************************************/
void board_button_initialize(void)
{
(void)sam_configgpio(GPIO_SW0);
}
/****************************************************************************
* 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
* 8-bit bit set with each bit associated with a button. See the BUTTON*
* definitions above for the meaning of each bit in the returned value.
*
****************************************************************************/
uint8_t board_buttons(void)
{
return sam_gpioread(GPIO_SW0) ? 0 : BUTTON_SW0_BIT;
}
/****************************************************************************
* Name: board_button_irq
*
* Description:
* This function may be called to register an interrupt handler that will
* be called when a button is depressed or released. The ID value is one
* of the BUTTON* definitions provided above. The previous interrupt
* handler address is returned (so that it may restored, if so desired).
*
* Configuration Notes:
* Configuration CONFIG_AVR32_GPIOIRQ must be selected to enable the
* overall GPIO IRQ feature and CONFIG_AVR32_GPIOIRQSETA and/or
* CONFIG_AVR32_GPIOIRQSETB must be enabled to select GPIOs to support
* interrupts on. For button support, bits 2 and 3 must be set in
* CONFIG_AVR32_GPIOIRQSETB (PB2 and PB3).
*
****************************************************************************/
#if defined(CONFIG_SAM34_GPIOA_IRQ) && defined(CONFIG_ARCH_IRQBUTTONS)
xcpt_t board_button_irq(int id, xcpt_t irqhandler)
{
xcpt_t oldhandler = NULL;
if (id == BUTTON_SW0)
{
irqstate_t flags;
/* Disable interrupts until we are done. This guarantees that the
* following operations are atomic.
*/
flags = irqsave();
/* Get the old button interrupt handler and save the new one */
oldhandler = g_irqsw0;
g_irqsw0 = irqhandler;
/* Are we attaching or detaching? */
if (irqhandler != NULL)
{
/* Configure the interrupt */
sam_gpioirq(GPIO_SW0);
(void)irq_attach(IRQ_SW0, irqhandler);
sam_gpioirqenable(IRQ_SW0);
}
else
{
/* Detach and disable the interrupt */
(void)irq_detach(IRQ_SW0);
sam_gpioirqdisable(IRQ_SW0);
}
irqrestore(flags);
}
/* Return the old button handler (so that it can be restored) */
return oldhandler;
}
#endif
#endif /* CONFIG_ARCH_BUTTONS */
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