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/****************************************************************************
* config/tm4c123g-launchpad/src/tm4c_buttons.c
*
* Copyright (C) 2015 Gregory Nutt. All rights reserved.
* Author: Bradley Noyes <bradley.noyes@trd2inc.com>
*
* 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 <nuttx/arch.h>
#include <arch/irq.h>
#include <arch/board/board.h>
#include "tiva_gpio.h"
#include "tm4c123g-launchpad.h"
#ifdef CONFIG_ARCH_BUTTONS
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
#ifdef CONFIG_ARCH_IRQBUTTONS
static xcpt_t g_irquser;
#endif
/****************************************************************************
* 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)
{
/* Unlock GPIOF from NMI to use it w/ buttons see Register 19 of GPIOs
* and see table 10-10 in datasheet for pins with special considerations.
*/
tiva_gpio_lockport(GPIO_SW2, false);
/* Configure the GPIO pins as inputs. NOTE that EXTI interrupts are
* configured for some pins but NOT used in this file
*/
tiva_configgpio(GPIO_SW1);
tiva_configgpio(GPIO_SW2);
/* Configure GPIO interrupts */
#ifdef CONFIG_ARCH_IRQBUTTONS
(void)tiva_gpioirqinitialize();
#endif
}
/****************************************************************************
* 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)
{
uint8_t ret = 0x0;
/* Check that state of each key. A LOW value means that the key is
* pressed.
*/
if (!tiva_gpioread(GPIO_SW1))
{
ret |= (1 << GPIO_PIN_4);
}
if (!tiva_gpioread(GPIO_SW2))
{
ret |= (1 << GPIO_PIN_0);
}
return ret;
}
/****************************************************************************
* 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).
*
****************************************************************************/
# ifdef CONFIG_ARCH_IRQBUTTONS
xcpt_t board_button_irq(int id, xcpt_t irqhandler)
{
xcpt_t oldhandler = NULL;
if (id == BUTTON_SW1 ||
id == BUTTON_SW2)
{
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_irquser;
g_irquser = irqhandler;
/* Are we attaching or detaching? */
if (irqhandler != NULL)
{
/* Configure the interrupt */
(void)tiva_gpioirqattach(CONFIG_TIVA_GPIOF_IRQS, irqhandler);
tiva_gpioirqenable(CONFIG_TIVA_GPIOF_IRQS);
}
else
{
/* Disable and detach the interrupt */
tiva_gpioirqdisable(CONFIG_TIVA_GPIOF_IRQS);
(void)tiva_gpioirqattach(CONFIG_TIVA_GPIOF_IRQS, NULL);
}
/* Configure the interrupt */
irqrestore(flags);
}
/* Return the old button handler (so that it can be restored) */
return oldhandler;
}
# endif
#endif /* CONFIG_ARCH_BUTTONS */
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