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drivers/ioexpander: Add support for PCA9557

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Datasheet: https://www.ti.com/lit/ds/symlink/pca9557.pdf

Signed-off-by: wangjianyu3 <wangjianyu3@xiaomi.com>
This commit is contained in:
wangjianyu3 2025-03-24 19:48:47 +08:00 • committed by Alan C. Assis
parent 5c2cfe8bac
commit b73d7f2922
5 changed files with 884 additions and 0 deletions
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31
drivers/ioexpander/Kconfig
View file

@ -312,6 +312,37 @@ config PCA9538_RETRY
endif # IOEXPANDER_PCA9538
config IOEXPANDER_PCA9557
bool "PCA9557 I2C IO expander"
default n
depends on I2C
---help---
Enable support for the NXP PCA9557 IO Expander
if IOEXPANDER_PCA9557
config PCA9557_SHADOW_MODE
bool "Use Shadow Mode instead of Read-Modify-Write Operations"
default n
---help---
This setting enables a mode where the output and pin
configuration registers are held in RAM.
With this for example we do not need to read back the
output-register every time we want to change one pin.
We do instead change the bit in the internal register
and then just write this register to the IO-Expander.
This reduces bus traffic and eliminates the problem of
EMC-caused toggling of output pins.
config PCA9557_RETRY
bool "Retry to send commands and data at I2C communication errors"
default n
---help---
Retry to send commands and data if a I2C-communication
error occurs (eg. caused by EMC).
endif # IOEXPANDER_PCA9557
config IOEXPANDER_TCA64XX
bool "TCA64XX I2C IO expander"
default n

4
drivers/ioexpander/Make.defs
View file

@ -54,6 +54,10 @@ ifeq ($(CONFIG_IOEXPANDER_PCA9538),y)
CSRCS += pca9538.c
endif
ifeq ($(CONFIG_IOEXPANDER_PCA9557),y)
CSRCS += pca9557.c
endif
ifeq ($(CONFIG_IOEXPANDER_TCA64XX),y)
CSRCS += tca64xx.c
endif

654
drivers/ioexpander/pca9557.c Normal file
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@ -0,0 +1,654 @@
/****************************************************************************
* drivers/ioexpander/pca9557.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 <stdbool.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/irq.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/kmalloc.h>
#include <nuttx/ioexpander/ioexpander.h>
#include "pca9557.h"
#if defined(CONFIG_IOEXPANDER_PCA9557)
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static inline int pca9557_i2c_write(FAR struct pca9557_dev_s *pca,
FAR const uint8_t *wbuffer, int wbuflen);
static inline int pca9557_i2c_writeread(FAR struct pca9557_dev_s *pca,
FAR const uint8_t *wbuffer,
int wbuflen, FAR uint8_t *rbuffer,
int rbuflen);
static int pca9557_setbit(FAR struct pca9557_dev_s *pca, uint8_t reg,
uint8_t pin, bool bitval);
static int pca9557_getbit(FAR struct pca9557_dev_s *pca, uint8_t reg,
uint8_t pin, FAR bool *val);
static int pca9557_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int direction);
static int pca9557_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int opt, FAR void *value);
static int pca9557_writepin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
bool value);
static int pca9557_readpin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value);
static int pca9557_readbuf(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value);
#ifdef CONFIG_IOEXPANDER_MULTIPIN
static int pca9557_getmultibits(FAR struct pca9557_dev_s *pca, uint8_t reg,
FAR uint8_t *pins, FAR bool *values,
int count);
static int pca9557_multiwritepin(FAR struct ioexpander_dev_s *dev,
FAR const uint8_t *pins,
FAR const bool *values, int count);
static int pca9557_multireadpin(FAR struct ioexpander_dev_s *dev,
FAR const uint8_t *pins,
FAR bool *values, int count);
static int pca9557_multireadbuf(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values,
int count);
#endif
/****************************************************************************
* Private Data
****************************************************************************/
/* I/O expander vtable */
static const struct ioexpander_ops_s g_pca9557_ops =
{
.ioe_direction = pca9557_direction,
.ioe_option = pca9557_option,
.ioe_writepin = pca9557_writepin,
.ioe_readpin = pca9557_readpin,
.ioe_readbuf = pca9557_readbuf,
#ifdef CONFIG_IOEXPANDER_MULTIPIN
.ioe_multiwritepin = pca9557_multiwritepin,
.ioe_multireadpin = pca9557_multireadpin,
.ioe_multireadbuf = pca9557_multireadbuf,
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: pca9557_i2c_write
*
* Description:
* Write to the I2C device.
*
****************************************************************************/
static inline int pca9557_i2c_write(FAR struct pca9557_dev_s *pca,
FAR const uint8_t *wbuffer, int wbuflen)
{
struct i2c_msg_s msg;
int ret;
/* Setup for the transfer */
msg.frequency = pca->config->frequency;
msg.addr = pca->config->address;
msg.flags = 0;
msg.buffer = (FAR uint8_t *)wbuffer; /* Override const */
msg.length = wbuflen;
/* Then perform the transfer. */
ret = I2C_TRANSFER(pca->i2c, &msg, 1);
return (ret >= 0) ? OK : ret;
}
/****************************************************************************
* Name: pca9557_i2c_writeread
*
* Description:
* Write to then read from the I2C device.
*
****************************************************************************/
static inline int pca9557_i2c_writeread(FAR struct pca9557_dev_s *pca,
FAR const uint8_t *wbuffer,
int wbuflen, FAR uint8_t *rbuffer,
int rbuflen)
{
struct i2c_config_s config;
/* Set up the configuration and perform the write-read operation */
config.frequency = pca->config->frequency;
config.address = pca->config->address;
config.addrlen = 7;
return i2c_writeread(pca->i2c, &config, wbuffer,
wbuflen, rbuffer, rbuflen);
}
/****************************************************************************
* Name: pca9557_setbit
*
* Description:
* Write a bit in a register pair
*
****************************************************************************/
static int pca9557_setbit(FAR struct pca9557_dev_s *pca, uint8_t reg,
uint8_t pin, bool bitval)
{
uint8_t buf[2];
int ret;
if (pin >= PCA9557_GPIO_NPINS)
{
return -ENXIO;
}
ret = nxrmutex_lock(&pca->lock);
if (ret < 0)
{
return ret;
}
buf[0] = reg;
#ifdef CONFIG_PCA9557_SHADOW_MODE
/* Get the shadowed register value */
buf[1] = pca->sreg[reg];
#else
/* Get the register value from the IO-Expander */
ret = pca9557_i2c_writeread(pca, &buf[0], 1, &buf[1], 1);
if (ret < 0)
{
nxrmutex_unlock(&pca->lock);
return ret;
}
#endif
if (bitval)
{
buf[1] |= (1 << pin);
}
else
{
buf[1] &= ~(1 << pin);
}
ret = pca9557_i2c_write(pca, buf, 2);
#ifdef CONFIG_PCA9557_RETRY
if (ret != OK)
{
/* Try again (only once) */
ret = pca9557_i2c_write(pca, buf, 2);
}
#endif
#ifdef CONFIG_PCA9557_SHADOW_MODE
if (ret == OK)
{
/* Save the new register value in the shadow register */
pca->sreg[reg] = buf[1];
}
#endif
nxrmutex_unlock(&pca->lock);
return ret;
}
/****************************************************************************
* Name: pca9557_getbit
*
* Description:
* Get a bit from a register pair
*
****************************************************************************/
static int pca9557_getbit(FAR struct pca9557_dev_s *pca, uint8_t reg,
uint8_t pin, FAR bool *val)
{
uint8_t buf;
int ret;
if (pin >= PCA9557_GPIO_NPINS)
{
return -ENXIO;
}
ret = nxrmutex_lock(&pca->lock);
if (ret < 0)
{
return ret;
}
ret = pca9557_i2c_writeread(pca, &reg, 1, &buf, 1);
if (ret < 0)
{
nxrmutex_unlock(&pca->lock);
return ret;
}
#ifdef CONFIG_PCA9557_SHADOW_MODE
/* Save the new register value in the shadow register */
pca->sreg[reg] = buf;
#endif
*val = (buf >> pin) & 1;
nxrmutex_unlock(&pca->lock);
return OK;
}
/****************************************************************************
* Name: pca9557_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 pca9557_direction(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int direction)
{
if (direction != IOEXPANDER_DIRECTION_IN &&
direction != IOEXPANDER_DIRECTION_OUT)
{
return -EINVAL;
}
return pca9557_setbit((FAR struct pca9557_dev_s *)dev, PCA9557_REG_CONFIG,
pin, (direction == IOEXPANDER_DIRECTION_IN));
}
/****************************************************************************
* Name: pca9557_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 pca9557_option(FAR struct ioexpander_dev_s *dev, uint8_t pin,
int opt, FAR void *value)
{
int ret = -EINVAL;
if (opt == IOEXPANDER_OPTION_INVERT)
{
ret = pca9557_setbit((FAR struct pca9557_dev_s *)dev,
PCA9557_REG_POLINV, pin,
((uintptr_t)value == IOEXPANDER_VAL_INVERT));
}
return ret;
}
/****************************************************************************
* Name: pca9557_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 pca9557_writepin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
bool value)
{
return pca9557_setbit((FAR struct pca9557_dev_s *)dev, PCA9557_REG_OUTPUT,
pin, value);
}
/****************************************************************************
* Name: pca9557_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 pca9557_readpin(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value)
{
return pca9557_getbit((FAR struct pca9557_dev_s *)dev, PCA9557_REG_INPUT,
pin, value);
}
/****************************************************************************
* Name: pca9557_readbuf
*
* Description:
* Read the buffered pin level.
* This can be different from the actual pin state. Required.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The index of the pin
* valptr - Pointer to a buffer where the level is stored.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int pca9557_readbuf(FAR struct ioexpander_dev_s *dev, uint8_t pin,
FAR bool *value)
{
return pca9557_getbit((FAR struct pca9557_dev_s *)dev, PCA9557_REG_OUTPUT,
pin, value);
}
#ifdef CONFIG_IOEXPANDER_MULTIPIN
/****************************************************************************
* Name: pca9557_getmultibits
*
* Description:
* Read multiple bits from PCA9557 registers.
*
****************************************************************************/
static int pca9557_getmultibits(FAR struct pca9557_dev_s *pca, uint8_t reg,
FAR uint8_t *pins, FAR bool *values,
int count)
{
uint8_t val;
int ret = OK;
int i;
int pin;
ret = nxrmutex_lock(&pca->lock);
if (ret < 0)
{
return ret;
}
ret = pca9557_i2c_writeread(pca, &reg, 1, &val, 1);
if (ret < 0)
{
nxrmutex_unlock(&pca->lock);
return ret;
}
#ifdef CONFIG_PCA9557_SHADOW_MODE
/* Save the new register value in the shadow register */
pca->sreg[reg] = val;
#endif
/* Read the requested bits */
for (i = 0; i < count; i++)
{
pin = pins[i];
if (pin >= PCA9557_GPIO_NPINS)
{
nxrmutex_unlock(&pca->lock);
return -ENXIO;
}
values[i] = (val >> pin) & 1;
}
nxrmutex_unlock(&pca->lock);
return OK;
}
/****************************************************************************
* Name: pca9557_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
*
****************************************************************************/
static int pca9557_multiwritepin(FAR struct ioexpander_dev_s *dev,
FAR const uint8_t *pins,
FAR const bool *values, int count)
{
FAR struct pca9557_dev_s *pca = (FAR struct pca9557_dev_s *)dev;
uint8_t reg = PCA9557_REG_OUTPUT;
uint8_t buf[2];
int ret;
int i;
int pin;
/* Get exclusive access to the PCA9557 */
ret = nxrmutex_lock(&pca->lock);
if (ret < 0)
{
return ret;
}
/* Start by reading both registers, whatever the pins to change. We could
* attempt to read one port only if all pins were on the same port, but
* this would not save much.
*/
#ifndef CONFIG_PCA9557_SHADOW_MODE
ret = pca9557_i2c_writeread(pca, &reg, 1, &buf[1], 1);
if (ret < 0)
{
nxrmutex_unlock(&pca->lock);
return ret;
}
#else
/* In Shadow-Mode we "read" the pin status from the shadow registers */
buf[1] = pca->sreg[reg];
#endif
/* Apply the user defined changes */
for (i = 0; i < count; i++)
{
pin = pins[i];
if (pin >= PCA9557_GPIO_NPINS)
{
nxrmutex_unlock(&pca->lock);
return -ENXIO;
}
if (values[i])
{
buf[1] |= (1 << pin);
}
else
{
buf[1] &= ~(1 << pin);
}
}
/* Now write back the new pins states */
buf[0] = reg;
#ifdef CONFIG_PCA9557_SHADOW_MODE
/* Save the new register values in the shadow register */
pca->sreg[reg] = buf[1];
#endif
ret = pca9557_i2c_write(pca, buf, 2);
nxrmutex_unlock(&pca->lock);
return ret;
}
/****************************************************************************
* Name: pca9557_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
*
****************************************************************************/
static int pca9557_multireadpin(FAR struct ioexpander_dev_s *dev,
FAR const uint8_t *pins,
FAR bool *values, int count)
{
return pca9557_getmultibits((FAR struct pca9557_dev_s *)dev,
PCA9557_REG_INPUT, pins, values, count);
}
/****************************************************************************
* Name: pca9557_multireadbuf
*
* Description:
* Read the buffered level of multiple pins. This routine may be faster
* than individual pin accesses. Optional.
*
* Input Parameters:
* dev - Device-specific state data
* pin - The index of the pin
* valptr - Pointer to a buffer where the buffered levels are stored.
*
* Returned Value:
* 0 on success, else a negative error code
*
****************************************************************************/
static int pca9557_multireadbuf(FAR struct ioexpander_dev_s *dev,
FAR uint8_t *pins, FAR bool *values,
int count)
{
return pca9557_getmultibits((FAR struct pca9557_dev_s *)dev,
PCA9557_REG_OUTPUT, pins, values, count);
}
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: pca9557_initialize
*
* Description:
* Initialize a PCA9557 I2C device.
*
****************************************************************************/
FAR struct ioexpander_dev_s *
pca9557_initialize(FAR struct i2c_master_s *i2cdev,
FAR struct pca9557_config_s *config)
{
FAR struct pca9557_dev_s *pcadev;
DEBUGASSERT(i2cdev != NULL && config != NULL);
if (config->set_nreset_pin)
{
config->set_nreset_pin(true);
}
/* Allocate the device state structure */
pcadev = kmm_zalloc(sizeof(struct pca9557_dev_s));
if (!pcadev)
{
return NULL;
}
/* Initialize the device state structure */
pcadev->i2c = i2cdev;
pcadev->dev.ops = &g_pca9557_ops;
pcadev->config = config;
nxrmutex_init(&pcadev->lock);
return &pcadev->dev;
}
#endif /* CONFIG_IOEXPANDER_PCA9557 */

96
drivers/ioexpander/pca9557.h Normal file
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@ -0,0 +1,96 @@
/****************************************************************************
* drivers/ioexpander/pca9557.h
*
* 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.
*
****************************************************************************/
#ifndef __DRIVERS_IOEXPANDER_PCA9557_H
#define __DRIVERS_IOEXPANDER_PCA9557_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/wdog.h>
#include <nuttx/clock.h>
#include <nuttx/mutex.h>
#include <nuttx/wqueue.h>
#include <nuttx/ioexpander/ioexpander.h>
#include <nuttx/ioexpander/pca9557.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/irq.h>
#if defined(CONFIG_IOEXPANDER) && defined(CONFIG_IOEXPANDER_PCA9557)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Prerequisites:
* CONFIG_I2C
* I2C support is required
* CONFIG_IOEXPANDER
* Enables support for the PCA9557 I/O expander
*
* CONFIG_IOEXPANDER_PCA9557
* Enables support for the PCA9557 driver (Needs CONFIG_INPUT)
*/
/* PCA9557 Resources ********************************************************/
#define PCA9557_GPIO_NPINS 8
#define PCA9557_MAXDEVS 8
/* I2C frequency */
#define PCA9557_I2C_MAXFREQUENCY 400000 /* 400KHz */
/* PCA9557 Registers ********************************************************/
#define PCA9557_REG_NUM 4
#define PCA9557_REG_INPUT 0x00
#define PCA9557_REG_OUTPUT 0x01
#define PCA9557_REG_POLINV 0x02
#define PCA9557_REG_CONFIG 0x03
/****************************************************************************
* Public Types
****************************************************************************/
/* This structure represents the state of the PCA9557 driver */
struct pca9557_dev_s
{
struct ioexpander_dev_s dev; /* Nested structure to allow casting
* as public gpio expander. */
#ifdef CONFIG_PCA9557_SHADOW_MODE
uint8_t sreg[PCA9557_REG_NUM]; /* Shadowed registers */
#endif
FAR struct pca9557_config_s *config; /* Board configuration data */
FAR struct i2c_master_s *i2c; /* Saved I2C driver instance */
rmutex_t lock; /* Mutual exclusion */
};
#endif /* CONFIG_IOEXPANDER && CONFIG_IOEXPANDER_PCA9557 */
#endif /* __DRIVERS_IOEXPANDER_PCA9557_H */

99
include/nuttx/ioexpander/pca9557.h Normal file
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@ -0,0 +1,99 @@
/****************************************************************************
* include/nuttx/ioexpander/pca9557.h
*
* 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.
*
****************************************************************************/
#ifndef __INCLUDE_NUTTX_IOEXPANDER_PCA9557_H
#define __INCLUDE_NUTTX_IOEXPANDER_PCA9557_H
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <nuttx/i2c/i2c_master.h>
#include <stdbool.h>
/****************************************************************************
* Public Types
****************************************************************************/
/* A reference to a structure of this type must be passed to the PCA9557
* driver when the driver is instantiated. This structure provides
* information about the configuration of the PCA9557 and provides some
* board-specific hooks.
*
* Memory for this structure is provided by the caller. It is not copied by
* the driver and is presumed to PERSIST while the driver is active. The
* memory must be writeable because, under certain circumstances, the driver
* may modify the frequency.
*/
struct pca9557_config_s
{
/* Device characterization */
uint8_t address; /* 7-bit I2C address (only bits 0-6 used) */
uint32_t frequency; /* I2C or SPI frequency */
/* Sets the state of the PCA9557's nReset pin, not invoke if NULL */
CODE void (*set_nreset_pin)(bool state);
};
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: pca9557_initialize
*
* Description:
* Instantiate and configure the pca9557 device driver to use the provided
* I2C device instance.
*
* Input Parameters:
* dev - 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 *
pca9557_initialize(FAR struct i2c_master_s *dev,
FAR struct pca9557_config_s *config);
#ifdef __cplusplus
}
#endif
#endif /* __INCLUDE_NUTTX_IOEXPANDER_PCA9557_H */