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apache / nuttx / refs/heads/master / . / arch / arm / src / sam34 / sam4l_gpio.c
blob: 7fc6e94bd19d9a02bc4eb7e1b9cc2212022aff9e [file] [log] [blame]
/****************************************************************************
* arch/arm/src/sam34/sam4l_gpio.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 <time.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <nuttx/spinlock.h>
#include <arch/board/board.h>
#include "arm_internal.h"
#include "chip.h"
#include "sam_gpio.h"
#include "hardware/sam4l_gpio.h"
/****************************************************************************
* Private Data
****************************************************************************/
#ifdef CONFIG_DEBUG_GPIO_INFO
static spinlock_t g_configgpio_lock = SP_UNLOCKED;
static const char g_portchar[4] =
{
'A', 'B', 'C', 'D'
};
#endif
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: sam_gpiobase
*
* Description:
* Return the base address of the GPIO register set
*
****************************************************************************/
static inline uintptr_t sam_gpiobase(gpio_pinset_t cfgset)
{
int port = (cfgset & GPIO_PORT_MASK) >> GPIO_PORT_SHIFT;
return SAM_GPION_BASE(port);
}
/****************************************************************************
* Name: sam_gpiopin
*
* Description:
* Returun the base address of the GPIO register set
*
****************************************************************************/
static inline int sam_gpiopin(gpio_pinset_t cfgset)
{
return 1 << ((cfgset & GPIO_PIN_MASK) >> GPIO_PIN_SHIFT);
}
/****************************************************************************
* Name: sam_configinput
*
* Description:
* Configure a GPIO input pin based on bit-encoded description of the pin.
* This function serves the dual role of putting all pins into a known,
* initial state. Hence, it is overkill for what really needs to be done.
*
****************************************************************************/
static int sam_configinput(uintptr_t base,
uint32_t pin,
gpio_pinset_t cfgset)
{
/* Disable interrupts on the pin */
putreg32(pin, base + SAM_GPIO_IERC_OFFSET);
/* Disable the output driver and select the GPIO function */
putreg32(pin, base + SAM_GPIO_ODERC_OFFSET);
putreg32(pin, base + SAM_GPIO_GPERS_OFFSET);
/* Clear peripheral-only settings (just to make debug easier) */
putreg32(pin, base + SAM_GPIO_PMR0C_OFFSET);
putreg32(pin, base + SAM_GPIO_PMR1C_OFFSET);
putreg32(pin, base + SAM_GPIO_PMR2C_OFFSET);
putreg32(pin, base + SAM_GPIO_EVERC_OFFSET);
/* Clear output-only settings (just to make debug easier) */
putreg32(pin, base + SAM_GPIO_ODCR0C_OFFSET);
putreg32(pin, base + SAM_GPIO_ODCR1C_OFFSET);
putreg32(pin, base + SAM_GPIO_OSRR0C_OFFSET);
/* Clear the interrupt configuration (just to make debug easier) */
putreg32(pin, base + SAM_GPIO_IMR0C_OFFSET);
putreg32(pin, base + SAM_GPIO_IMR1C_OFFSET);
/* Enable/disable the pull-up as requested */
if ((cfgset & GPIO_PULL_UP) != 0)
{
putreg32(pin, base + SAM_GPIO_PUERS_OFFSET);
}
else
{
putreg32(pin, base + SAM_GPIO_PUERC_OFFSET);
}
if ((cfgset & GPIO_PULL_DOWN) != 0)
{
putreg32(pin, base + SAM_GPIO_PDERS_OFFSET);
}
else
{
putreg32(pin, base + SAM_GPIO_PDERC_OFFSET);
}
/* Check if glitch filtering should be enabled */
if ((cfgset & GPIO_GLITCH_FILTER) != 0)
{
putreg32(pin, base + SAM_GPIO_GFERS_OFFSET);
}
else
{
putreg32(pin, base + SAM_GPIO_GFERC_OFFSET);
}
/* Check if the input Schmitt trigger should be enabled */
if ((cfgset & GPIO_SCHMITT_TRIGGER) != 0)
{
putreg32(pin, base + SAM_GPIO_STERS_OFFSET);
}
else
{
putreg32(pin, base + SAM_GPIO_STERC_OFFSET);
}
return OK;
}
/****************************************************************************
* Name: sam_configinterrupt
*
* Description:
* Configure a GPIO input pin based on bit-encoded description of the pin.
*
****************************************************************************/
static inline int sam_configinterrupt(uintptr_t base, uint32_t pin,
gpio_pinset_t cfgset)
{
int ret;
/* Just configure the pin as an input, then set the interrupt
* configuration. Here we exploit the fact that sam_configinput() enabled
* both rising and falling edges.
*/
ret = sam_configinput(base, pin, cfgset);
if (ret == OK)
{
/* Disable rising and falling edge interrupts as requested
* {IMR1, IMR0} Interrupt Mode
*
* 00 Pin Change <-- We already have this
* 01 Rising Edge <-- GPIO_INT_RISING
* 10 Falling Edge <-- GPIO_INT_FALLING
* 11 Reserved
*/
gpio_pinset_t edges = (cfgset & GPIO_INT_MASK);
if (edges == GPIO_INT_RISING)
{
/* Rising only.. disable interrupts on the falling edge */
putreg32(pin, base + SAM_GPIO_IMR0S_OFFSET);
}
else if (edges == GPIO_INT_FALLING)
{
/* Falling only.. disable interrupts on the rising edge */
putreg32(pin, base + SAM_GPIO_IMR1S_OFFSET);
}
}
return ret;
}
/****************************************************************************
* Name: sam_configoutput
*
* Description:
* Configure a GPIO output pin based on bit-encoded description of the pin.
*
* Assumption:
* sam_configinput has been called to put the pin into the default input
* state:
*
* GPER -> GPIO
* PMD0-2 -> zeroed
* ODER -> disabled
* PUER+PDER -> No pull up- or down.
* IER -> Interrupt disabled
* IMR0-1 -> zeroed
* Glitch filter -> disabled
* Output drive -> lowest
* Slew control -> disabled
* Schmitt trigger -> disabled
* Peripheral events -> disabled
*
****************************************************************************/
static inline int sam_configoutput(uintptr_t base, uint32_t pin,
gpio_pinset_t cfgset)
{
/* Set the output drive strength
*
* {ODCR1, ODCR0} Output drive strength
*
* 00 Lowest drive strength
* 01 ...
* 10 ...
* 11 Highest drive strength
*/
switch (cfgset & GPIO_DRIVE_MASK)
{
default:
case GPIO_DRIVE_LOW: /* OCDR1=0 OCDR0=0 */
break; /* This is the current setting */
case GPIO_DRIVE_MEDLOW: /* OCDR1=0 OCDR0=1 */
putreg32(pin, base + SAM_GPIO_ODCR0S_OFFSET);
break;
case GPIO_DRIVE_MEDHIGH: /* OCDR1=1 OCDR0=0 */
putreg32(pin, base + SAM_GPIO_ODCR1S_OFFSET);
break;
case GPIO_DRIVE_HIGH: /* OCDR1=1 OCDR0=1 */
putreg32(pin, base + SAM_GPIO_ODCR0S_OFFSET);
putreg32(pin, base + SAM_GPIO_ODCR1S_OFFSET);
break;
}
/* Set the output slew control is requested */
if ((cfgset & GPIO_SLEW) != 0)
{
putreg32(pin, base + SAM_GPIO_OSRR0S_OFFSET);
}
/* Enable the output driver */
putreg32(pin, base + SAM_GPIO_ODERS_OFFSET);
/* And set the initial value of the output */
sam_gpiowrite(cfgset, ((cfgset & GPIO_OUTPUT_SET) != 0));
return OK;
}
/****************************************************************************
* Name: sam_configperiph
*
* Description:
* Configure a GPIO pin driven by a peripheral based on bit-encoded
* description of the pin.
*
* Assumption:
* sam_configinput has been called to put the pin into the default input
* state:
*
* GPER -> GPIO
* PMD0-2 -> zeroed
* ODER -> disabled
* PUER+PDER -> No pull up- or down.
* IER -> Interrupt disabled
* IMR0-1 -> zeroed
* Glitch filter -> disabled
* Output drive -> lowest
* Slew control -> disabled
* Schmitt trigger -> disabled
* Peripheral events -> disabled
*
****************************************************************************/
static inline int sam_configperiph(uintptr_t base, uint32_t pin,
gpio_pinset_t cfgset)
{
gpio_pinset_t edges;
/* Select the peripheral function.
*
* {PMR2, PMR1, PMR0} selects peripheral function:
*
* 000 A 100 E
* 001 B 101 F
* 010 C 110 G
* 011 D 111 H
*/
switch (cfgset & GPIO_FUNC_MASK)
{
default:
case _GPIO_FUNCA: /* Function A 000 */
break; /* We already have this configuration */
case _GPIO_FUNCD: /* Function D 011 */
putreg32(pin, base + SAM_GPIO_PMR1S_OFFSET);
break;
case _GPIO_FUNCB: /* Function B 001 */
putreg32(pin, base + SAM_GPIO_PMR0S_OFFSET);
break;
case _GPIO_FUNCG: /* Function G 110 */
putreg32(pin, base + SAM_GPIO_PMR2S_OFFSET);
case _GPIO_FUNCC: /* Function C 010 */
putreg32(pin, base + SAM_GPIO_PMR1S_OFFSET);
break;
case _GPIO_FUNCE: /* Function E 100 */
putreg32(pin, base + SAM_GPIO_PMR2S_OFFSET);
break;
case _GPIO_FUNCF: /* Function F 101 */
putreg32(pin, base + SAM_GPIO_PMR0S_OFFSET);
break;
case _GPIO_FUNCH: /* Function H 111 */
putreg32(pin, base + SAM_GPIO_PMR0S_OFFSET);
putreg32(pin, base + SAM_GPIO_PMR1S_OFFSET);
putreg32(pin, base + SAM_GPIO_PMR2S_OFFSET);
break;
}
/* Check if glitch filtering should be enabled */
if ((cfgset & GPIO_GLITCH_FILTER) != 0)
{
putreg32(pin, base + SAM_GPIO_GFERS_OFFSET);
}
/* Disable rising and falling edge events as requested (of course,
* these do nothing unless events are also enabled.
*
* {IMR1, IMR0} Interrupt Mode
*
* 00 Pin Change <-- We already have this
* 01 Rising Edge <-- GPIO_INT_RISING
* 10 Falling Edge <-- GPIO_INT_FALLING
* 11 Reserved
*/
edges = (cfgset & GPIO_INT_MASK);
if (edges == GPIO_INT_RISING)
{
/* Rising only.. disable interrupts on the falling edge */
putreg32(pin, base + SAM_GPIO_IMR0S_OFFSET);
}
else if (edges == GPIO_INT_FALLING)
{
/* Falling only.. disable interrupts on the rising edge */
putreg32(pin, base + SAM_GPIO_IMR1S_OFFSET);
}
/* REVISIT: Should event generation be enabled now? I am assuming so */
if ((cfgset & GPIO_PERIPH_EVENTS) != 0)
{
/* Rising only.. disable interrupts on the falling edge */
putreg32(pin, base + SAM_GPIO_EVERS_OFFSET);
}
/* Finally, drive the pen from the peripheral */
putreg32(pin, base + SAM_GPIO_GPERC_OFFSET);
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: sam_configgpio
*
* Description:
* Configure a GPIO pin based on bit-encoded description of the pin.
*
****************************************************************************/
int sam_configgpio(gpio_pinset_t cfgset)
{
gpio_pinset_t inputset;
uintptr_t base = sam_gpiobase(cfgset);
uint32_t pin = sam_gpiopin(cfgset);
int ret;
/* Put the GPIO in a known state. A generic GPIO input pin. */
inputset = GPIO_INPUT | (cfgset & (GPIO_PORT_MASK | GPIO_PIN_MASK));
ret = sam_configinput(base, pin, inputset);
if (ret == OK)
{
/* Then put the GPIO into the requested state */
switch (cfgset & GPIO_MODE_MASK)
{
case GPIO_INPUT:
ret = sam_configinput(base, pin, cfgset);
break;
case GPIO_OUTPUT:
ret = sam_configoutput(base, pin, cfgset);
break;
case GPIO_PERIPHERAL:
ret = sam_configperiph(base, pin, cfgset);
break;
case GPIO_INTERRUPT:
ret = sam_configinterrupt(base, pin, cfgset);
break;
default:
ret = -EINVAL;
break;
}
}
return ret;
}
/****************************************************************************
* Name: sam_gpiowrite
*
* Description:
* Write one or zero to the selected GPIO pin
*
****************************************************************************/
void sam_gpiowrite(gpio_pinset_t pinset, bool value)
{
uintptr_t base = sam_gpiobase(pinset);
uint32_t pin = sam_gpiopin(pinset);
if (value)
{
putreg32(pin, base + SAM_GPIO_OVRS_OFFSET);
}
else
{
putreg32(pin, base + SAM_GPIO_OVRC_OFFSET);
}
}
/****************************************************************************
* Name: sam_gpioread
*
* Description:
* Read one or zero from the selected GPIO pin
*
****************************************************************************/
bool sam_gpioread(gpio_pinset_t pinset)
{
uintptr_t base = sam_gpiobase(pinset);
uint32_t pin = sam_gpiopin(pinset);
return (getreg32(base + SAM_GPIO_PVR_OFFSET) & pin) != 0;
}
/****************************************************************************
* Function: sam_dumpgpio
*
* Description:
* Dump all GPIO registers associated with the base address of the provided
* pinset.
*
****************************************************************************/
#ifdef CONFIG_DEBUG_GPIO_INFO
int sam_dumpgpio(uint32_t pinset, const char *msg)
{
irqstate_t flags;
uintptr_t base;
unsigned int pin;
unsigned int port;
/* Get the base address associated with the PIO port */
pin = sam_gpiopin(pinset);
port = (pinset & GPIO_PORT_MASK) >> GPIO_PORT_SHIFT;
base = SAM_GPION_BASE(port);
/* The following requires exclusive access to the GPIO registers */
flags = spin_lock_irqsave(&g_configgpio_lock);
gpioinfo("GPIO%c pinset: %08x base: %08x -- %s\n",
g_portchar[port], pinset, base, msg);
gpioinfo(" GPER: %08x PMR0: %08x PMR1: %08x PMR2: %08x\n",
getreg32(base + SAM_GPIO_GPER_OFFSET),
getreg32(base + SAM_GPIO_PMR0_OFFSET),
getreg32(base + SAM_GPIO_PMR1_OFFSET),
getreg32(base + SAM_GPIO_PMR2_OFFSET));
gpioinfo(" ODER: %08x OVR: %08x PVR: %08x PUER: %08x\n",
getreg32(base + SAM_GPIO_ODER_OFFSET),
getreg32(base + SAM_GPIO_OVR_OFFSET),
getreg32(base + SAM_GPIO_PVR_OFFSET),
getreg32(base + SAM_GPIO_PUER_OFFSET));
gpioinfo(" PDER: %08x IER: %08x IMR0: %08x IMR1: %08x\n",
getreg32(base + SAM_GPIO_PDER_OFFSET),
getreg32(base + SAM_GPIO_IER_OFFSET),
getreg32(base + SAM_GPIO_IMR0_OFFSET),
getreg32(base + SAM_GPIO_IMR1_OFFSET));
gpioinfo(" GFER: %08x IFR: %08x ODCR0: %08x ODCR1: %08x\n",
getreg32(base + SAM_GPIO_GFER_OFFSET),
getreg32(base + SAM_GPIO_IFR_OFFSET),
getreg32(base + SAM_GPIO_ODCR0_OFFSET),
getreg32(base + SAM_GPIO_ODCR1_OFFSET));
gpioinfo(" OSRR0: %08x EVER: %08x PARAM: %08x VERS: %08x\n",
getreg32(base + SAM_GPIO_OSRR0_OFFSET),
getreg32(base + SAM_GPIO_EVER_OFFSET),
getreg32(base + SAM_GPIO_PARAMETER_OFFSET),
getreg32(base + SAM_GPIO_VERSION_OFFSET));
spin_unlock_irqrestore(&g_configgpio_lock, flags);
return OK;
}
#endif