/****************************************************************************
* arch/mips/src/pic32mx/pic32mx-gpio.c
*
* Copyright (C) 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* 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 <assert.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <arch/board/board.h>
#include "up_arch.h"
#include "pic32mx-gpio.h"
#include "pic32mx-internal.h"
#ifdef CONFIG_GPIO_IRQ
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
static xcpt_t g_cnisrs[IOPORT_NUMCN];
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: Inline PIN set field extractors
****************************************************************************/
static inline bool pic32mx_input(uint16_t pinset)
{
return ((pinset & GPIO_MODE_MASK) != GPIO_INPUT);
}
static inline bool pic32mx_interrupt(uint16_t pinset)
{
return ((pinset & GPIO_INTERRUPT) != 0);
}
static inline bool pic32mx_pullup(uint16_t pinset)
{
return ((pinset & GPIO_INT_MASK) == GPIO_PUINT);
}
/****************************************************************************
* Name: pic32mx_cninterrupt
*
* Description:
* Change notification interrupt handler.
*
****************************************************************************/
static int pic32mx_cninterrupt(int irq, FAR void *context)
{
int status;
int ret = OK;
int i;
/* Call all attached handlers */
for (i = 0; i < IOPORT_NUMCN; i++)
{
/* Is this one attached */
if (g_cnisrs[i])
{
/* Call the attached handler */
status = g_cnisrs[i](irq, context);
/* Keep track of the status of the last handler that failed */
if (status < 0)
{
ret = status;
}
}
/* Clear the pending interrupt */
up_clrpend_irq(PIC32MX_IRQ_CN);
return ret;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pic32mx_gpioirqinitialize
*
* Description:
* Initialize logic to support a GPIO change notification interrupts.
* This function is called internally by the system on power up and should
* not be called again.
*
****************************************************************************/
void pic32mx_gpioirqinitialize(void)
{
int ret;
/* Attach the change notice interrupt handler */
ret = irqattach(PIC32MX_IRQ_CN, pic32mx_cninterrupt);
DEBUGASSERT(ret == OK);
/* Set the interrupt priority */
#ifdef CONFIG_ARCH_IRQPRIO
ret = up_prioritize_irq(PIC32MX_IRQ_CN, CONFIG_PIC32MX_CNPRIO);
DEBUGASSERT(ret == OK);
#endif
/* Reset all registers and enable the CN module */
putreg32(IOPORT_CN_ALL, PIC32MX_IOPORT_CNENCLR);
putreg32(IOPORT_CN_ALL, PIC32MX_IOPORT_CNPUECLR);
putreg32(IOPORT_CNCON_ON, PIC32MX_IOPORT_CNCON);
/* And enable the GPIO interrupt */
ret = up_enable_irq(PIC32MX_IRQSRC_CN);
DEBUGASSERT(ret == OK);
}
/****************************************************************************
* Name: pic32mx_gpioattach
*
* Description:
* Attach an interrupt service routine to a GPIO interrupt. This will
* also reconfigure the pin as an interrupting input. The change
* notification number is associated with all interrupt-capabile GPIO pins.
* The association could, however, differ from part to part and must be
* provided by the caller.
*
* When an interrupt occurs, it is due to a change on the GPIO input pin.
* In that case, all attached handlers will be called. Each handler must
* maintain state and determine if the unlying GPIO input value changed.
*
* Parameters:
* - pinset: GPIO pin configuration
* - cn: The change notification number associated with the pin.
* - handler: Interrupt handler (may be NULL to detach)
*
* Returns:
* The previous value of the interrupt handler function pointer. This
* value may, for example, be used to restore the previous handler when
* multiple handlers are used.
*
****************************************************************************/
xcpt_t pic32mx_gpioattach(uint32_t pinset, unsigned int cn, xcpt_t handler)
{
xcpt_t oldhandler = NULL;
irqstate_t flags;
DEBUGASSERT(cn < IOPORT_NUMCN);
/* First verify that the pinset is configured as an interrupting input */
if (pic32mx_input(pinset) && pic32mx_interrupt(pinset))
{
/* Get the previously attached handler as the return value */
flags = irqsave();
oldhandler = g_cnisrs[cn];
/* Are we attaching or detaching? */
if (handler != NULL)
{
/* Attaching... Make sure that the GPIO is properly configured as
* an input
*/
pic32mx_configgpio(pinset);
/* Pull-up requested? */
if (pic32mx_pullup(pinset))
{
putreg32(1 << cn, PIC32MX_IOPORT_CNPUESET);
}
else
{
putreg32(1 << cn, PIC32MX_IOPORT_CNPUECLR);
}
}
else
{
/* Make sure that any further interrupts are disabled.
* (disable the pull-up as well).
*/
putreg32(1 << cn, PIC32MX_IOPORT_CNENCLR);
putreg32(1 << cn, PIC32MX_IOPORT_CNPUECLR);
}
/* Set the new handler (perhaps NULLifying the current handler) */
g_cnisrs[cn] = handler;
irqrestore(flags);
}
return oldhandler;
}
/****************************************************************************
* Name: pic32mx_gpioirqenable
*
* Description:
* Enable the interrupt for specified GPIO IRQ
*
****************************************************************************/
void pic32mx_gpioirqenable(unsigned int cn)
{
DEBUGASSERT(cn < IOPORT_NUMCN);
putreg32(1 << cn, PIC32MX_IOPORT_CNENSET);
}
/****************************************************************************
* Name: pic32mx_gpioirqdisable
*
* Description:
* Disable the interrupt for specified GPIO IRQ
*
****************************************************************************/
void pic32mx_gpioirqdisable(unsigned int cn)
{
DEBUGASSERT(cn < IOPORT_NUMCN);
putreg32(1 << cn, PIC32MX_IOPORT_CNENCLR);
}
#endif /* CONFIG_GPIO_IRQ */
