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incubator-nuttx/drivers/ioexpander/tca64xx.c

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/****************************************************************************
* drivers/ioexpander/tca64xx.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.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/wdog.h>
#include <nuttx/ioexpander/ioexpander.h>
#include <nuttx/ioexpander/tca64xx.h>
#include "tca64xx.h"
#ifdef CONFIG_IOEXPANDER_TCA64XX
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef MAX
# define MAX(a,b) (((a) > (b)) ? (a) : (b))
#endif
#ifndef MIN
# define MIN(a,b) (((a) < (b)) ? (a) : (b))
#endif
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/* TCA64xx Helpers */
static int tca64_lock(FAR struct tca64_dev_s *priv);
static FAR const struct tca64_part_s *tca64_getpart(
FAR struct tca64_dev_s *priv);
static uint8_t tca64_ngpios(FAR struct tca64_dev_s *priv);
static uint8_t tca64_input_reg(FAR struct tca64_dev_s *priv, uint8_t pin);
static uint8_t tca64_output_reg(FAR struct tca64_dev_s *priv, uint8_t pin);
static uint8_t tca64_polarity_reg(FAR struct tca64_dev_s *priv, uint8_t pin);
static uint8_t tca64_config_reg(FAR struct tca64_dev_s *priv, uint8_t pin);
static int tca64_getreg(FAR struct tca64_dev_s *priv, uint8_t regaddr,
FAR uint8_t *regval, unsigned int count);
static int tca64_putreg(struct tca64_dev_s *priv, uint8_t regaddr,
FAR uint8_t *regval, unsigned int count);
/* I/O Expander Methods */
static int tca64_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int dir);
static int tca64_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int opt, void *regval);
static int tca64_writepin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
bool value);
static int tca64_readpin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value);
#ifdef CONFIG_IOEXPANDER_MULTIPIN
static int tca64_multiwritepin(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values, int count);
static int tca64_multireadpin(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values, int count);
#endif
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
static FAR void *tca64_attach(FAR struct ioexpander_dev_s *dev,
ioe_pinset_t pinset, ioe_callback_t callback, FAR void *arg);
static int tca64_detach(FAR struct ioexpander_dev_s *dev, FAR void *handle);
#endif
#ifdef CONFIG_TCA64XX_INT_ENABLE
static void tca64_int_update(FAR struct tca64_dev_s *priv,
ioe_pinset_t input, ioe_pinset_t mask);
static void tca64_register_update(FAR struct tca64_dev_s *priv);
static void tca64_irqworker(void *arg);
static void tca64_interrupt(FAR void *arg);
#ifdef CONFIG_TCA64XX_INT_POLL
static void tca64_poll_expiry(wdparm_t arg);
#endif
#endif
/****************************************************************************
* Private Data
****************************************************************************/
#ifndef CONFIG_TCA64XX_MULTIPLE
/* If only a single device is supported, then the driver state structure may
* as well be pre-allocated.
*/
static struct tca64_dev_s g_tca64;
#endif
/* I/O expander vtable */
static const struct ioexpander_ops_s g_tca64_ops =
{
tca64_direction,
tca64_option,
tca64_writepin,
tca64_readpin,
tca64_readpin
#ifdef CONFIG_IOEXPANDER_MULTIPIN
, tca64_multiwritepin
, tca64_multireadpin
, tca64_multireadpin
#endif
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
, tca64_attach
, tca64_detach
#endif
};
/* TCA64 part data */
static const struct tca64_part_s g_tca64_parts[TCA64_NPARTS] =
{
{
TCA6408_PART,
MIN(TCA6408_NR_GPIOS, CONFIG_IOEXPANDER_NPINS),
TCA6408_INPUT_REG,
TCA6408_OUTPUT_REG,
TCA6408_POLARITY_REG,
TCA6408_CONFIG_REG,
},
{
TCA6416_PART,
MIN(TCA6416_NR_GPIOS, CONFIG_IOEXPANDER_NPINS),
TCA6416_INPUT0_REG,
TCA6416_OUTPUT0_REG,
TCA6416_POLARITY0_REG,
TCA6416_CONFIG0_REG,
},
{
TCA6424_PART,
MIN(TCA6424_NR_GPIOS, CONFIG_IOEXPANDER_NPINS),
TCA6424_INPUT0_REG,
TCA6424_OUTPUT0_REG,
TCA6424_POLARITY0_REG,
TCA6424_CONFIG0_REG,
},
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: tca64_lock
*
* Description:
* Get exclusive access to the I/O Expander
*
****************************************************************************/
static int tca64_lock(FAR struct tca64_dev_s *priv)
{
return nxsem_wait_uninterruptible(&priv->exclsem);
}
#define tca64_unlock(p) nxsem_post(&(p)->exclsem)
/****************************************************************************
* Name: tca64_getpart
*
* Description:
* Look up information for the selected part
*
****************************************************************************/
static FAR const struct tca64_part_s *tca64_getpart(
FAR struct tca64_dev_s *priv)
{
DEBUGASSERT(priv != NULL && priv->config != NULL &&
priv->config->part < TCA64_NPARTS);
return &g_tca64_parts[priv->config->part];
}
/****************************************************************************
* Name: tca64_ngpios
*
* Description:
* Return the number of GPIOs supported by the selected part
*
****************************************************************************/
static uint8_t tca64_ngpios(FAR struct tca64_dev_s *priv)
{
FAR const struct tca64_part_s *part = tca64_getpart(priv);
return part->tp_ngpios;
}
/****************************************************************************
* Name: tca64_input_reg
*
* Description:
* Return the address of the input register for the specified pin.
*
****************************************************************************/
static uint8_t tca64_input_reg(FAR struct tca64_dev_s *priv, uint8_t pin)
{
FAR const struct tca64_part_s *part = tca64_getpart(priv);
uint8_t reg = part->tp_input;
DEBUGASSERT(pin <= part->tp_ngpios);
return reg + (pin >> 3);
}
/****************************************************************************
* Name: tca64_output_reg
*
* Description:
* Return the address of the output register for the specified pin.
*
****************************************************************************/
static uint8_t tca64_output_reg(FAR struct tca64_dev_s *priv, uint8_t pin)
{
FAR const struct tca64_part_s *part = tca64_getpart(priv);
uint8_t reg = part->tp_output;
DEBUGASSERT(pin <= part->tp_ngpios);
return reg + (pin >> 3);
}
/****************************************************************************
* Name: tca64_polarity_reg
*
* Description:
* Return the address of the polarity register for the specified pin.
*
****************************************************************************/
static uint8_t tca64_polarity_reg(FAR struct tca64_dev_s *priv, uint8_t pin)
{
FAR const struct tca64_part_s *part = tca64_getpart(priv);
uint8_t reg = part->tp_output;
DEBUGASSERT(pin <= part->tp_ngpios);
return reg + (pin >> 3);
}
/****************************************************************************
* Name: tca64_config_reg
*
* Description:
* Return the address of the configuration register for the specified pin.
*
****************************************************************************/
static uint8_t tca64_config_reg(FAR struct tca64_dev_s *priv, uint8_t pin)
{
FAR const struct tca64_part_s *part = tca64_getpart(priv);
uint8_t reg = part->tp_config;
DEBUGASSERT(pin <= part->tp_ngpios);
return reg + (pin >> 3);
}
/****************************************************************************
* Name: tca64_getreg
*
* Description:
* Read an 8-bit value from a TCA64xx register
*
****************************************************************************/
static int tca64_getreg(FAR struct tca64_dev_s *priv, uint8_t regaddr,
FAR uint8_t *regval, unsigned int count)
{
struct i2c_msg_s msg[2];
int ret;
DEBUGASSERT(priv != NULL && priv->i2c != NULL && priv->config != NULL);
/* Set up for the transfer */
msg[0].frequency = TCA64XX_I2C_MAXFREQUENCY,
msg[0].addr = priv->config->address,
msg[0].flags = 0,
msg[0].buffer = &regaddr,
msg[0].length = 1,
msg[1].frequency = TCA64XX_I2C_MAXFREQUENCY,
msg[1].addr = priv->config->address,
msg[1].flags = I2C_M_READ,
msg[1].buffer = regval,
msg[1].length = count,
/* Perform the transfer */
ret = I2C_TRANSFER(priv->i2c, msg, 2);
if (ret < 0)
{
gpioerr("ERROR: I2C addr=%02x regaddr=%02x: failed, ret=%d!\n",
priv->config->address, regaddr, ret);
return ret;
}
else
{
gpioinfo("I2C addr=%02x regaddr=%02x: read %02x\n",
priv->config->address, regaddr, *regval);
return OK;
}
}
/****************************************************************************
* Name: tca64_putreg
*
* Description:
* Write an 8-bit value to a TCA64xx register
*
****************************************************************************/
static int tca64_putreg(struct tca64_dev_s *priv, uint8_t regaddr,
FAR uint8_t *regval, unsigned int count)
{
struct i2c_msg_s msg[1];
uint8_t cmd[2];
int ret;
int i;
DEBUGASSERT(priv != NULL && priv->i2c != NULL && priv->config != NULL);
/* Set up for the transfer */
cmd[0] = regaddr;
for (i = 0; i < count; i++)
{
cmd[i + 1] = regval[i];
}
msg[0].frequency = TCA64XX_I2C_MAXFREQUENCY,
msg[0].addr = priv->config->address,
msg[0].flags = 0,
msg[0].buffer = cmd,
msg[0].length = count + 1,
ret = I2C_TRANSFER(priv->i2c, msg, 1);
if (ret < 0)
{
gpioerr("ERROR: claddr=%02x, regaddr=%02x: failed, ret=%d!\n",
priv->config->address, regaddr, ret);
return ret;
}
else
{
gpioinfo("claddr=%02x, regaddr=%02x, regval=%02x\n",
priv->config->address, regaddr, regval);
return OK;
}
}
/****************************************************************************
* Name: tca64_direction
*
* Description:
* Set the direction of an ioexpander pin. Required.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The index of the pin to alter in this call
* dir - One of the IOEXPANDER_DIRECTION_ macros
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int tca64_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int direction)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
uint8_t regaddr;
uint8_t regval;
int ret;
if (direction != IOEXPANDER_DIRECTION_IN &&
direction != IOEXPANDER_DIRECTION_OUT)
{
return -EINVAL;
}
DEBUGASSERT(priv != NULL && priv->config != NULL &&
pin < CONFIG_IOEXPANDER_NPINS);
gpioinfo("I2C addr=%02x pin=%u direction=%s\n",
priv->config->address, pin,
(direction == IOEXPANDER_DIRECTION_IN) ? "IN" : "OUT");
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the Configuration Register associated with this pin. The
* Configuration Register configures the direction of the I/O pins.
*/
regaddr = tca64_config_reg(priv, pin);
ret = tca64_getreg(priv, regaddr, &regval, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to read config register at %u: %d\n",
regaddr, ret);
goto errout_with_lock;
}
/* Set the pin direction in the I/O Expander */
if (direction == IOEXPANDER_DIRECTION_IN)
{
/* Configure pin as input. If a bit in the configuration register is
* set to 1, the corresponding port pin is enabled as an input with a
* high-impedance output driver.
*/
regval |= (1 << (pin & 7));
}
else /* if (direction == IOEXPANDER_DIRECTION_OUT) */
{
/* Configure pin as output. If a bit in this register is cleared to
* 0, the corresponding port pin is enabled as an output.
*
* REVISIT: The value of output has not been selected! This might
* put a glitch on the output.
*/
regval &= ~(1 << (pin & 7));
}
/* Write back the modified register content */
ret = tca64_putreg(priv, regaddr, &regval, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to write config register at %u: %d\n",
regaddr, ret);
}
errout_with_lock:
tca64_unlock(priv);
return ret;
}
/****************************************************************************
* Name: tca64_option
*
* Description:
* Set pin options. Required.
* Since all IO expanders have various pin options, this API allows setting
* pin options in a flexible way.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The index of the pin to alter in this call
* opt - One of the IOEXPANDER_OPTION_ macros
* val - The option's value
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int tca64_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int opt, FAR void *value)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
int ret = -ENOSYS;
DEBUGASSERT(priv != NULL && priv->config != NULL);
gpioinfo("I2C addr=%02x pin=%u option=%u\n",
priv->config->address, pin, opt);
/* Check for pin polarity inversion. The Polarity Inversion Register
* allows polarity inversion of pins defined as inputs by the
* Configuration Register. If a bit in this register is set, the
* corresponding port pin's polarity is inverted. If a bit in this
* register is cleared, the corresponding port pin's original polarity
* is retained.
*/
if (opt == IOEXPANDER_OPTION_INVERT)
{
uint8_t regaddr;
uint8_t polarity;
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the polarity register */
regaddr = tca64_polarity_reg(priv, pin);
ret = tca64_getreg(priv, regaddr, &polarity, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to read polarity register at %u: %d\n",
regaddr, ret);
tca64_unlock(priv);
return ret;
}
/* Set/clear the pin option */
if ((uintptr_t)value == IOEXPANDER_VAL_INVERT)
{
polarity |= (1 << (pin & 7));
}
else
{
polarity &= ~(1 << (pin & 7));
}
/* Write back the modified register */
ret = tca64_putreg(priv, regaddr, &polarity, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to read polarity register at %u: %d\n",
regaddr, ret);
}
tca64_unlock(priv);
}
#ifdef CONFIG_TCA64XX_INT_ENABLE
/* Interrupt configuration */
else if (opt == IOEXPANDER_OPTION_INTCFG)
{
unsigned int ival = (unsigned int)((uintptr_t)value);
ioe_pinset_t bit = ((ioe_pinset_t)1 << pin);
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
switch (ival)
{
case IOEXPANDER_VAL_HIGH: /* Interrupt on high level */
priv->trigger &= ~bit;
priv->level[0] |= bit;
priv->level[1] &= ~bit;
break;
case IOEXPANDER_VAL_LOW: /* Interrupt on low level */
priv->trigger &= ~bit;
priv->level[0] &= ~bit;
priv->level[1] |= bit;
break;
case IOEXPANDER_VAL_RISING: /* Interrupt on rising edge */
priv->trigger |= bit;
priv->level[0] |= bit;
priv->level[1] &= ~bit;
break;
case IOEXPANDER_VAL_FALLING: /* Interrupt on falling edge */
priv->trigger |= bit;
priv->level[0] &= ~bit;
priv->level[1] |= bit;
break;
case IOEXPANDER_VAL_BOTH: /* Interrupt on both edges */
priv->trigger |= bit;
priv->level[0] |= bit;
priv->level[1] |= bit;
break;
case IOEXPANDER_VAL_DISABLE:
break;
default:
ret = -EINVAL;
}
tca64_unlock(priv);
}
#endif
return ret;
}
/****************************************************************************
* Name: tca64_writepin
*
* Description:
* Set the pin level. Required.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The index of the pin to alter in this call
* val - The pin level. Usually TRUE will set the pin high,
* except if OPTION_INVERT has been set on this pin.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int tca64_writepin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
bool value)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
uint8_t regaddr;
uint8_t regval;
int ret;
DEBUGASSERT(priv != NULL && priv->config != NULL &&
pin < CONFIG_IOEXPANDER_NPINS);
gpioinfo("I2C addr=%02x pin=%u value=%u\n",
priv->config->address, pin, value);
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the output register. */
regaddr = tca64_output_reg(priv, pin);
ret = tca64_getreg(priv, regaddr, &regval, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to read output register at %u: %d\n",
regaddr, ret);
goto errout_with_lock;
}
/* Set output pins default value (before configuring it as output) The
* Output Port Register shows the outgoing logic levels of the pins
* defined as outputs by the Configuration Register.
*/
if (value != 0)
{
regval |= (1 << (pin & 7));
}
else
{
regval &= ~(1 << (pin & 7));
}
/* Write the modified output register value */
ret = tca64_putreg(priv, regaddr, &regval, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to write output register at %u: %d\n",
regaddr, ret);
}
errout_with_lock:
tca64_unlock(priv);
return ret;
}
/****************************************************************************
* Name: tca64_readpin
*
* Description:
* Read the actual PIN level. This can be different from the last value
* written to this pin. Required.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The index of the pin
* valptr - Pointer to a buffer where the pin level is stored. Usually TRUE
* if the pin is high, except if OPTION_INVERT has been set on
* this pin.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int tca64_readpin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
uint8_t regaddr;
uint8_t regval;
int ret;
DEBUGASSERT(priv != NULL && priv->config != NULL &&
pin < CONFIG_IOEXPANDER_NPINS && value != NULL);
gpioinfo("I2C addr=%02x, pin=%u\n", priv->config->address, pin);
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the input register for this pin
*
* The Input Port Register reflects the incoming logic levels of the pins,
* regardless of whether the pin is defined as an input or an output by
* the Configuration Register. They act only on read operation.
*/
regaddr = tca64_input_reg(priv, pin);
ret = tca64_getreg(priv, regaddr, &regval, 1);
if (ret < 0)
{
gpioerr("ERROR: Failed to read input register at %u: %d\n",
regaddr, ret);
goto errout_with_lock;
}
#ifdef CONFIG_TCA64XX_INT_ENABLE
/* Update the input status with the 8 bits read from the expander */
tca64_int_update(priv, (ioe_pinset_t)regval << (pin & ~7),
(ioe_pinset_t)0xff << (pin & ~7));
#endif
/* Return 0 or 1 to indicate the state of pin */
*value = (bool)((regval >> (pin & 7)) & 1);
ret = OK;
errout_with_lock:
tca64_unlock(priv);
return ret;
}
/****************************************************************************
* Name: tca64_multiwritepin
*
* Description:
* Set the pin level for multiple pins. This routine may be faster than
* individual pin accesses. Optional.
*
* Input Parameters:
* dev - Device-specific state data
* pins - The list of pin indexes to alter in this call
* val - The list of pin levels.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
#ifdef CONFIG_IOEXPANDER_MULTIPIN
static int tca64_multiwritepin(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values,
int count)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
ioe_pinset_t pinset;
uint8_t regaddr;
uint8_t ngpios;
uint8_t nregs;
uint8_t pin;
int ret;
int i;
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the output registers for pin 0 through the number of supported
* pins.
*/
ngpios = tca64_ngpios(priv);
nregs = (ngpios + 7) >> 3;
pinset = 0;
regaddr = tca64_output_reg(priv, 0);
ret = tca64_getreg(priv, regaddr, (FAR uint8_t *)&pinset, nregs);
if (ret < 0)
{
gpioerr("ERROR: Failed to read %u output registers at %u: %d\n",
nregs, regaddr, ret);
goto errout_with_lock;
}
/* Apply the user defined changes */
for (i = 0; i < count; i++)
{
pin = pins[i];
DEBUGASSERT(pin < CONFIG_IOEXPANDER_NPINS);
if (values[i])
{
pinset |= ((ioe_pinset_t)1 << pin);
}
else
{
pinset &= ~((ioe_pinset_t)1 << pin);
}
}
/* Now write back the new pins states */
ret = tca64_putreg(priv, regaddr, (FAR uint8_t *)&pinset, nregs);
if (ret < 0)
{
gpioerr("ERROR: Failed to write %u output registers at %u: %d\n",
nregs, regaddr, ret);
}
errout_with_lock:
tca64_unlock(priv);
return ret;
}
#endif
/****************************************************************************
* Name: tca64_multireadpin
*
* Description:
* Read the actual level for multiple pins. This routine may be faster than
* individual pin accesses. Optional.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The list of pin indexes to read
* valptr - Pointer to a buffer where the pin levels are stored.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
#ifdef CONFIG_IOEXPANDER_MULTIPIN
static int tca64_multireadpin(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values,
int count)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
ioe_pinset_t pinset;
uint8_t regaddr;
uint8_t ngpios;
uint8_t nregs;
uint8_t pin;
int ret;
int i;
DEBUGASSERT(priv != NULL && priv->config != NULL && pins != NULL &&
values != NULL && count > 0);
gpioinfo("I2C addr=%02x, count=%u\n", priv->config->address, count);
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the input register for pin 0 through the number of supported pins.
*
* The Input Port Register reflects the incoming logic levels of the pins,
* regardless of whether the pin is defined as an input or an output by
* the Configuration Register. They act only on read operation.
*/
ngpios = tca64_ngpios(priv);
nregs = (ngpios + 7) >> 3;
pinset = 0;
regaddr = tca64_input_reg(priv, 0);
ret = tca64_getreg(priv, regaddr, (FAR uint8_t *)&pinset, nregs);
if (ret < 0)
{
gpioerr("ERROR: Failed to read input %u registers at %u: %d\n",
nregs, regaddr, ret);
goto errout_with_lock;
}
/* Update the input status with the 8 bits read from the expander */
for (i = 0; i < count; i++)
{
pin = pins[i];
DEBUGASSERT(pin < CONFIG_IOEXPANDER_NPINS);
values[i] = (((pinset >> pin) & 1) != 0);
}
#ifdef CONFIG_TCA64XX_INT_ENABLE
/* Update the input status with the 32 bits read from the expander */
tca64_int_update(priv, pinset, PINSET_ALL);
#endif
errout_with_lock:
tca64_unlock(priv);
return ret;
}
#endif
/****************************************************************************
* Name: tca64_attach
*
* Description:
* Attach and enable a pin interrupt callback function.
*
* Input Parameters:
* dev - Device-specific state data
* pinset - The set of pin events that will generate the callback
* callback - The pointer to callback function. NULL will detach the
* callback.
* arg - User-provided callback argument
*
* Returned Value:
* A non-NULL handle value is returned on success. This handle may be
* used later to detach and disable the pin interrupt.
*
****************************************************************************/
#ifdef CONFIG_TCA64XX_INT_ENABLE
static FAR void *tca64_attach(FAR struct ioexpander_dev_s *dev,
ioe_pinset_t pinset, ioe_callback_t callback,
FAR void *arg)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
FAR void *handle = NULL;
int i;
int ret;
/* Get exclusive access to the I/O Expander */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Find and available in entry in the callback table */
for (i = 0; i < CONFIG_TCA64XX_INT_NCALLBACKS; i++)
{
/* Is this entry available (i.e., no callback attached) */
if (priv->cb[i].cbfunc == NULL)
{
/* Yes.. use this entry */
priv->cb[i].pinset = pinset;
priv->cb[i].cbfunc = callback;
priv->cb[i].cbarg = arg;
handle = &priv->cb[i];
break;
}
}
tca64_unlock(priv);
return handle;
}
/****************************************************************************
* Name: tca64_detach
*
* Description:
* Detach and disable a pin interrupt callback function.
*
* Input Parameters:
* dev - Device-specific state data
* handle - The non-NULL opaque value return by tca64_attch()
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int tca64_detach(FAR struct ioexpander_dev_s *dev, FAR void *handle)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)dev;
FAR struct tca64_callback_s *cb = (FAR struct tca64_callback_s *)handle;
DEBUGASSERT(priv != NULL && cb != NULL);
DEBUGASSERT((uintptr_t)cb >= (uintptr_t)&priv->cb[0] &&
(uintptr_t)cb <=
(uintptr_t)&priv->cb[CONFIG_TCA64XX_INT_NCALLBACKS - 1]);
UNUSED(priv);
cb->pinset = 0;
cb->cbfunc = NULL;
cb->cbarg = NULL;
return OK;
}
#endif
/****************************************************************************
* Name: tca64_int_update
*
* Description:
* Check for pending interrupts.
*
****************************************************************************/
#ifdef CONFIG_TCA64XX_INT_ENABLE
static void tca64_int_update(FAR struct tca64_dev_s *priv,
ioe_pinset_t input,
ioe_pinset_t mask)
{
ioe_pinset_t diff;
irqstate_t flags;
int ngios = tca64_ngpios(priv);
int pin;
flags = enter_critical_section();
/* Check the changed bits from last read */
input = (priv->input & ~mask) | (input & mask);
diff = priv->input ^ input;
priv->input = input;
/* TCA64XX doesn't support irq trigger, we have to do this in software. */
for (pin = 0; pin < ngios; pin++)
{
if (TCA64_EDGE_SENSITIVE(priv, pin))
{
/* Edge triggered. Was there a change in the level? */
if ((diff & 1) != 0)
{
/* Set interrupt as a function of edge type */
if (((input & 1) == 0 && TCA64_EDGE_FALLING(priv, pin)) ||
((input & 1) != 0 && TCA64_EDGE_RISING(priv, pin)))
{
priv->intstat |= ((ioe_pinset_t)1 << pin);
}
}
}
else /* if (TCA64_LEVEL_SENSITIVE(priv, pin)) */
{
/* Level triggered. Set intstat bit if match in level type. */
if (((input & 1) != 0 && TCA64_LEVEL_HIGH(priv, pin)) ||
((input & 1) == 0 && TCA64_LEVEL_LOW(priv, pin)))
{
priv->intstat |= ((ioe_pinset_t)1 << pin);
}
}
diff >>= 1;
input >>= 1;
}
leave_critical_section(flags);
}
#endif
/****************************************************************************
* Name: tc64_update_registers
*
* Description:
* Read all pin states and update pending interrupts.
*
* Input Parameters:
* dev - Device-specific state data
* pins - The list of pin indexes to alter in this call
* val - The list of pin levels.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
#ifdef CONFIG_TCA64XX_INT_ENABLE
static void tca64_register_update(FAR struct tca64_dev_s *priv)
{
ioe_pinset_t pinset;
uint8_t regaddr;
uint8_t ngpios;
uint8_t nregs;
int ret;
/* Read the input register for pin 0 through the number of supported pins.
*
* The Input Port Register reflects the incoming logic levels of the pins,
* regardless of whether the pin is defined as an input or an output by
* the Configuration Register. They act only on read operation.
*/
ngpios = tca64_ngpios(priv);
nregs = (ngpios + 7) >> 3;
pinset = 0;
regaddr = tca64_input_reg(priv, 0);
ret = tca64_getreg(priv, regaddr, (FAR uint8_t *)&pinset, nregs);
if (ret < 0)
{
gpioerr("ERROR: Failed to read input %u registers at %u: %d\n",
nregs, regaddr, ret);
return;
}
/* Update the input status with the 32 bits read from the expander */
tca64_int_update(priv, pinset, PINSET_ALL);
}
#endif
/****************************************************************************
* Name: tca64_irqworker
*
* Description:
* Handle GPIO interrupt events (this function actually executes in the
* context of the worker thread).
*
****************************************************************************/
#ifdef CONFIG_TCA64XX_INT_ENABLE
static void tca64_irqworker(void *arg)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)arg;
ioe_pinset_t pinset;
uint8_t regaddr;
uint8_t ngpios;
uint8_t nregs;
int ret;
int i;
DEBUGASSERT(priv != NULL && priv->config != NULL);
/* Get exclusive access to read inputs and assess pending interrupts. */
ret = tca64_lock(priv);
if (ret < 0)
{
return ret;
}
/* Read the input register for pin 0 through the number of supported pins.
*
* The Input Port Register reflects the incoming logic levels of the pins,
* regardless of whether the pin is defined as an input or an output by
* the Configuration Register. They act only on read operation.
*/
ngpios = tca64_ngpios(priv);
nregs = (ngpios + 7) >> 3;
pinset = 0;
regaddr = tca64_input_reg(priv, 0);
ret = tca64_getreg(priv, regaddr, (FAR uint8_t *)&pinset, nregs);
if (ret < 0)
{
gpioerr("ERROR: Failed to read input %u registers at %u: %d\n",
nregs, regaddr, ret);
tca64_unlock(priv);
goto errout_with_restart;
}
/* Update the input status with the 32 bits read from the expander */
tca64_int_update(priv, pinset, PINSET_ALL);
/* Sample and clear the pending interrupts. */
pinset = priv->intstat;
priv->intstat = 0;
tca64_unlock(priv);
/* Perform pin interrupt callbacks */
for (i = 0; i < CONFIG_TCA64XX_INT_NCALLBACKS; i++)
{
/* Is this entry valid (i.e., callback attached)? */
if (priv->cb[i].cbfunc != NULL)
{
/* Did any of the requested pin interrupts occur? */
ioe_pinset_t match = pinset & priv->cb[i].pinset;
if (match != 0)
{
/* Yes.. perform the callback */
priv->cb[i].cbfunc(&priv->dev, match,
priv->cb[i].cbarg);
}
}
}
errout_with_restart:
#ifdef CONFIG_TCA64XX_INT_POLL
/* Check for pending interrupts */
tca64_register_update(priv);
/* Re-start the poll timer */
sched_lock();
ret = wd_start(&priv->wdog, TCA64XX_POLLDELAY,
tca64_poll_expiry, (wdparm_t)priv);
if (ret < 0)
{
gpioerr("ERROR: Failed to start poll timer\n");
}
#endif
/* Re-enable interrupts */
priv->config->enable(priv->config, true);
#ifdef CONFIG_TCA64XX_INT_POLL
sched_unlock();
#endif
}
#endif
/****************************************************************************
* Name: tca64_interrupt
*
* Description:
* Handle GPIO interrupt events (this function executes in the
* context of the interrupt).
*
****************************************************************************/
#ifdef CONFIG_TCA64XX_INT_ENABLE
static void tca64_interrupt(FAR void *arg)
{
FAR struct tca64_dev_s *priv = (FAR struct tca64_dev_s *)arg;
DEBUGASSERT(priv != NULL && priv->config != NULL);
/* Defer interrupt processing to the worker thread. This is not only
* much kinder in the use of system resources but is probably necessary
* to access the I/O expander device.
*
* Notice that further GPIO interrupts are disabled until the work is
* actually performed. This is to prevent overrun of the worker thread.
* Interrupts are re-enabled in tca64_irqworker() when the work is
* completed.
*/
if (work_available(&priv->work))
{
#ifdef CONFIG_TCA64XX_INT_POLL
/* Cancel the poll timer */
wd_cancel(&priv->wdog);
#endif
/* Disable interrupts */
priv->config->enable(priv->config, false);
/* Schedule interrupt related work on the high priority worker
* thread.
*/
work_queue(HPWORK, &priv->work, tca64_irqworker,
(FAR void *)priv, 0);
}
}
#endif
/****************************************************************************
* Name: tca64_poll_expiry
*
* Description:
* The poll timer has expired; check for missed interrupts
*
* Input Parameters:
* Standard wdog expiration arguments.
*
****************************************************************************/
#if defined(CONFIG_TCA64XX_INT_ENABLE) && defined(CONFIG_TCA64XX_INT_POLL)
static void tca64_poll_expiry(wdparm_t arg)
{
FAR struct tca64_dev_s *priv;
priv = (FAR struct tca64_dev_s *)arg;
DEBUGASSERT(priv != NULL && priv->config != NULL);
/* Defer interrupt processing to the worker thread. This is not only
* much kinder in the use of system resources but is probably necessary
* to access the I/O expander device.
*
* Notice that further GPIO interrupts are disabled until the work is
* actually performed. This is to prevent overrun of the worker thread.
* Interrupts are re-enabled in tca64_irqworker() when the work is
* completed.
*/
if (work_available(&priv->work))
{
/* Disable interrupts */
priv->config->enable(priv->config, false);
/* Schedule interrupt related work on the high priority worker
* thread.
*/
work_queue(HPWORK, &priv->work, tca64_irqworker, priv, 0);
}
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tca64_initialize
*
* Description:
* Instantiate and configure the TCA64xx device driver to use the provided
* I2C device instance.
*
* Input Parameters:
* i2c - An I2C driver instance
* minor - The device i2c address
* config - Persistent board configuration data
*
* Returned Value:
* an ioexpander_dev_s instance on success, NULL on failure.
*
****************************************************************************/
FAR struct ioexpander_dev_s *tca64_initialize(FAR struct i2c_master_s *i2c,
FAR struct tca64_config_s *config)
{
FAR struct tca64_dev_s *priv;
int ret;
#ifdef CONFIG_TCA64XX_MULTIPLE
/* Allocate the device state structure */
priv = (FAR struct tca64_dev_s *)kmm_zalloc(sizeof(struct tca64_dev_s));
if (!priv)
{
gpioerr("ERROR: Failed to allocate driver instance\n");
return NULL;
}
#else
/* Use the one-and-only I/O Expander driver instance */
priv = &g_tca64;
#endif
/* Initialize the device state structure */
priv->dev.ops = &g_tca64_ops;
priv->i2c = i2c;
priv->config = config;
#ifdef CONFIG_TCA64XX_INT_ENABLE
/* Initial interrupt state: Edge triggered on both edges */
priv->trigger = PINSET_ALL; /* All edge triggered */
priv->level[0] = PINSET_ALL; /* All rising edge */
priv->level[1] = PINSET_ALL; /* All falling edge */
#ifdef CONFIG_TCA64XX_INT_POLL
/* Set up a timer to poll for missed interrupts */
ret = wd_start(&priv->wdog, TCA64XX_POLLDELAY,
tca64_poll_expiry, (wdparm_t)priv);
if (ret < 0)
{
gpioerr("ERROR: Failed to start poll timer\n");
}
#endif
/* Attach the I/O expander interrupt handler and enable interrupts */
priv->config->attach(config, tca64_interrupt, priv);
priv->config->enable(config, true);
#endif
nxsem_init(&priv->exclsem, 0, 1);
return &priv->dev;
}
#endif /* CONFIG_IOEXPANDER_TCA64XX */
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