incubator-nuttx/drivers/input/stmpe811_gpio.c

461 lines
13 KiB
C

/****************************************************************************
* drivers/input/stmpe811_gpio.c
*
* 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.
*
****************************************************************************/
/* References:
* "STMPE811 S-Touch advanced resistive touchscreen controller with 8-bit
* GPIO expander," Doc ID 14489 Rev 6, CD00186725, STMicroelectronics"
*/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/input/stmpe811.h>
#include "stmpe811.h"
#if defined(CONFIG_INPUT) && defined(CONFIG_INPUT_STMPE811) && !defined(CONFIG_STMPE811_GPIO_DISABLE)
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Data
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: stmpe811_gpioinit
*
* Description:
* Initialize the GPIO interrupt subsystem
*
* Input Parameters:
* handle - The handle previously returned by stmpe811_instantiate
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
static void stmpe811_gpioinit(FAR struct stmpe811_dev_s *priv)
{
uint8_t regval;
if ((priv->flags & STMPE811_FLAGS_GPIO_INITIALIZED) == 0)
{
/* Enable Clocking for GPIO */
regval = stmpe811_getreg8(priv, STMPE811_SYS_CTRL2);
regval &= ~SYS_CTRL2_GPIO_OFF;
stmpe811_putreg8(priv, STMPE811_SYS_CTRL2, regval);
/* Disable all GPIO interrupts */
stmpe811_putreg8(priv, STMPE811_GPIO_EN, 0);
/* Enable global GPIO interrupts */
#ifndef CONFIG_STMPE811_GPIOINT_DISABLE
regval = stmpe811_getreg8(priv, STMPE811_INT_EN);
regval |= INT_GPIO;
stmpe811_putreg8(priv, STMPE811_INT_EN, regval);
#endif
priv->flags |= STMPE811_FLAGS_GPIO_INITIALIZED;
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: stmpe811_gpioconfig
*
* Description:
* Configure an STMPE811 GPIO pin
*
* Input Parameters:
* handle - The handle previously returned by stmpe811_instantiate
* pinconfig - Bit-encoded pin configuration
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int stmpe811_gpioconfig(STMPE811_HANDLE handle, uint8_t pinconfig)
{
FAR struct stmpe811_dev_s *priv = (FAR struct stmpe811_dev_s *)handle;
int pin = (pinconfig & STMPE811_GPIO_PIN_MASK) >> STMPE811_GPIO_PIN_SHIFT;
uint8_t pinmask = (1 << pin);
uint8_t regval;
int ret;
DEBUGASSERT(handle && (unsigned)pin < STMPE811_GPIO_NPINS);
/* Get exclusive access to the device structure */
ret = nxsem_wait(&priv->exclsem);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* Make sure that the pin is not already in use */
if ((priv->inuse & pinmask) != 0)
{
ierr("ERROR: PIN%d is already in-use\n", pin);
nxsem_post(&priv->exclsem);
return -EBUSY;
}
/* Make sure that the GPIO block has been initialized */
stmpe811_gpioinit(priv);
/* Set the alternate function bit for the pin, making it a GPIO */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_AF);
regval |= pinmask;
stmpe811_putreg8(priv, STMPE811_GPIO_AF, regval);
/* Is the pin an input or an output? */
if ((pinconfig & STMPE811_GPIO_DIR) == STMPE811_GPIO_OUTPUT)
{
/* The pin is an output */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_DIR_REG);
regval |= pinmask;
stmpe811_putreg8(priv, STMPE811_GPIO_DIR_REG, regval);
/* Set its initial output value */
if ((pinconfig & STMPE811_GPIO_VALUE) != STMPE811_GPIO_ZERO)
{
/* Set the output value(s)e by writing to the SET register */
stmpe811_putreg8(priv, STMPE811_GPIO_SETPIN, (1 << pin));
}
else
{
/* Clear the output value(s) by writing to the CLR register */
stmpe811_putreg8(priv, STMPE811_GPIO_CLRPIN, (1 << pin));
}
}
else
{
/* It is an input */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_DIR_REG);
regval &= ~pinmask;
stmpe811_putreg8(priv, STMPE811_GPIO_DIR_REG, regval);
/* Set up the falling edge detection */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_FE);
if ((pinconfig & STMPE811_GPIO_FALLING) != 0)
{
regval |= pinmask;
}
else
{
regval &= ~pinmask;
}
stmpe811_putreg8(priv, STMPE811_GPIO_FE, regval);
/* Set up the rising edge detection */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_RE);
if ((pinconfig & STMPE811_GPIO_RISING) != 0)
{
regval |= pinmask;
}
else
{
regval &= ~pinmask;
}
stmpe811_putreg8(priv, STMPE811_GPIO_RE, regval);
/* Disable interrupts for now */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_EN);
regval &= ~pinmask;
stmpe811_putreg8(priv, STMPE811_GPIO_EN, regval);
}
/* Mark the pin as 'in use' */
priv->inuse |= pinmask;
nxsem_post(&priv->exclsem);
return OK;
}
/****************************************************************************
* Name: stmpe811_gpiowrite
*
* Description:
* Set or clear the GPIO output
*
* Input Parameters:
* handle - The handle previously returned by stmpe811_instantiate
* pinconfig - Bit-encoded pin configuration
* value = true: write logic '1'; false: write logic '0;
*
* Returned Value:
* None
*
****************************************************************************/
void stmpe811_gpiowrite(STMPE811_HANDLE handle, uint8_t pinconfig,
bool value)
{
FAR struct stmpe811_dev_s *priv = (FAR struct stmpe811_dev_s *)handle;
int pin = (pinconfig & STMPE811_GPIO_PIN_MASK) >> STMPE811_GPIO_PIN_SHIFT;
int ret;
DEBUGASSERT(handle && (unsigned)pin < STMPE811_GPIO_NPINS);
/* Get exclusive access to the device structure */
ret = nxsem_wait(&priv->exclsem);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return;
}
/* Are we setting or clearing outputs? */
if (value)
{
/* Set the output value(s)e by writing to the SET register */
stmpe811_putreg8(priv, STMPE811_GPIO_SETPIN, (1 << pin));
}
else
{
/* Clear the output value(s) by writing to the CLR register */
stmpe811_putreg8(priv, STMPE811_GPIO_CLRPIN, (1 << pin));
}
nxsem_post(&priv->exclsem);
}
/****************************************************************************
* Name: stmpe811_gpioread
*
* Description:
* Set or clear the GPIO output
*
* Input Parameters:
* handle - The handle previously returned by stmpe811_instantiate
* pinconfig - Bit-encoded pin configuration
* value - The location to return the state of the GPIO pin
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
int stmpe811_gpioread(STMPE811_HANDLE handle, uint8_t pinconfig, bool *value)
{
FAR struct stmpe811_dev_s *priv = (FAR struct stmpe811_dev_s *)handle;
int pin = (pinconfig & STMPE811_GPIO_PIN_MASK) >> STMPE811_GPIO_PIN_SHIFT;
uint8_t regval;
int ret;
DEBUGASSERT(handle && (unsigned)pin < STMPE811_GPIO_NPINS);
/* Get exclusive access to the device structure */
ret = nxsem_wait(&priv->exclsem);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
regval = stmpe811_getreg8(priv, STMPE811_GPIO_MPSTA);
*value = ((regval & STMPE811_GPIO_PIN(pin)) != 0);
nxsem_post(&priv->exclsem);
return OK;
}
/****************************************************************************
* Name: stmpe811_gpioattach
*
* Description:
* Attach to a GPIO interrupt input pin and enable interrupts on the pin.
* Using the value NULL for the handler address will disable interrupts
* from the pin anddetach the handler.
*
* NOTE: Callbacks do not occur from an interrupt handler but rather
* from the context of the worker thread.
*
* Input Parameters:
* handle - The handle previously returned by stmpe811_instantiate
* pinconfig - Bit-encoded pin configuration
* handler - The handler that will be called when the interrupt occurs.
*
* Returned Value:
* Zero is returned on success. Otherwise, a negated errno value is
* returned to indicate the nature of the failure.
*
****************************************************************************/
#ifndef CONFIG_STMPE811_GPIOINT_DISABLE
int stmpe811_gpioattach(STMPE811_HANDLE handle, uint8_t pinconfig,
stmpe811_handler_t handler)
{
FAR struct stmpe811_dev_s *priv = (FAR struct stmpe811_dev_s *)handle;
int pin = (pinconfig & STMPE811_GPIO_PIN_MASK) >> STMPE811_GPIO_PIN_SHIFT;
uint8_t regval;
int ret;
DEBUGASSERT(handle && (unsigned)pin < STMPE811_GPIO_NPINS);
/* Get exclusive access to the device structure */
ret = nxsem_wait(&priv->exclsem);
if (ret < 0)
{
ierr("ERROR: nxsem_wait failed: %d\n", ret);
return ret;
}
/* Make sure that the GPIO interrupt system has been gpioinitialized */
stmpe811_gpioinit(priv);
/* Set/clear the handler */
priv->handlers[pin] = handler;
/* If an handler has provided, then we are enabling interrupts */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_EN);
if (handler)
{
/* Enable interrupts for this GPIO */
regval |= STMPE811_GPIO_PIN(pin);
}
else
{
/* Disable interrupts for this GPIO */
regval &= ~STMPE811_GPIO_PIN(pin);
}
stmpe811_putreg8(priv, STMPE811_GPIO_EN, regval);
nxsem_post(&priv->exclsem);
return OK;
}
#endif
/****************************************************************************
* Name: stmpe811_gpioworker
*
* Description:
* Handle GPIO interrupt events (this function actually executes in the
* context of the worker thread).
*
****************************************************************************/
#ifndef CONFIG_STMPE811_GPIOINT_DISABLE
void stmpe811_gpioworker(FAR struct stmpe811_dev_s *priv)
{
uint8_t regval;
uint8_t pinmask;
int pin;
/* Get the set of pending GPIO interrupts */
regval = stmpe811_getreg8(priv, STMPE811_GPIO_INTSTA);
/* Look at each pin */
for (pin = 0; pin < STMPE811_GPIO_NPINS; pin++)
{
pinmask = GPIO_INT(pin);
if ((regval & pinmask) != 0)
{
/* Check if we have a handler for this interrupt (there should
* be one)
*/
if (priv->handlers[pin])
{
/* Interrupt is pending... dispatch the interrupt to the
* callback
*/
priv->handlers[pin](pin);
}
else
{
ierr("ERROR: No handler for PIN%d, GPIO_INTSTA: %02x\n",
pin, regval);
}
/* Clear the pending GPIO interrupt by writing a '1' to the
* pin position in the status register.
*/
stmpe811_putreg8(priv, STMPE811_GPIO_INTSTA, pinmask);
/* Must also clear the edge detection status bit
* this is _not documented_ as being required but is used in
* the SDK and without it a second interrupt will never trigger.
* Yep you have to "clear" _both_ the edge detection status and
* GPIO interrupt status register even in level mode.
*/
stmpe811_putreg8(priv, STMPE811_GPIO_ED, pinmask);
}
}
}
#endif
#endif /* CONFIG_INPUT && CONFIG_INPUT_STMPE811 && !CONFIG_STMPE811_GPIO_DISABLE */