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/****************************************************************************
* arch/arm/src/lpc43/lpc43_pin_config.c
*
* Copyright (C) 2012 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 <arch/board/board.h>
#include <nuttx/config.h>
#include <nuttx/arch.h>
#include <errno.h>
#include "up_arch.h"
#include "lpc43_pinconfig.h"
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: lpc43_pin_config
*
* Description:
* Configure a pin based on bit-encoded description of the pin.
*
* Input Value:
* 20-bit encoded value describing the pin.
*
* Returned Value:
* OK on success; A negated errno value on failure.
*
****************************************************************************/
int lpc43_pin_config(uint32_t pinconf)
{
unsigned int pinset = ((pinconf & PINCONF_PINS_MASK) >> PINCONF_PINS_SHIFT);
unsigned int pin = ((pinconf & PINCONF_PIN_MASK) >> PINCONF_PIN_SHIFT);
unsigned int func = ((pinconf & PINCONF_FUNC_MASK) >> PINCONF_FUNC_SHIFT);
uintptr_t regaddr;
uint32_t regval;
/* Set up common pin configurations */
regval = (func << SCU_PIN_MODE_SHIFT);
/* Enable/disable pull-down resistor */
if (PINCONF_IS_PULLDOWN(pinconf))
{
regval |= SCU_PIN_EPD; /* Set bit to enable */
}
if (!PINCONF_IS_PULLUP(pinconf))
{
regval |= SCU_PIN_EPUN; /* Set bit to disable */
}
/* Enable/disable input buffering */
if (PINCONF_INBUFFER_ENABLED(pinconf))
{
regval |= SCU_PIN_EZI; /* Set bit to enable */
}
/* Enable/disable glitch filtering */
if (!PINCONF_GLITCH_ENABLE(pinconf))
{
regval |= SCU_PIN_ZIF; /* Set bit to disable */
}
/* Only normal and high speed pins support the slew rate setting */
if (PINCONF_IS_SLEW_FAST(pinconf))
{
regval |= SCU_NDPIN_EHS; /* 0=slow; 1=fast */
}
/* Only high drive pins suppose drive strength */
switch (pinconf & PINCONF_DRIVE_MASK)
{
default:
case PINCONF_DRIVE_NORMAL: /* Normal-drive: 4 mA drive strength (or not high drive pin) */
regval |= SCU_HDPIN_EHD_NORMAL;
break;
case PINCONF_DRIVE_MEDIUM: /* Medium-drive: 8 mA drive strength */
regval |= SCU_HDPIN_EHD_MEDIUM;
break;
case PINCONF_DRIVE_HIGH: /* High-drive: 14 mA drive strength */
regval |= SCU_HDPIN_EHD_HIGH;
break;
case PINCONF_DRIVE_ULTRA: /* Ultra high-drive: 20 mA drive strength */
regval |= SCU_HDPIN_EHD_ULTRA;
break;
}
/* Get the address of the pin configuration register and save the new
* pin configuration.
*/
regaddr = LPC43_SCU_SFSP(pinset, pin);
putreg32(regval, regaddr);
return OK;
}
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