incubator-nuttx/drivers/ioexpander/pca9538.h

140 lines
4.6 KiB
C

/****************************************************************************
* drivers/ioexpander/pca9538.h
*
* 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_PCA9538_H
#define __DRIVERS_IOEXPANDER_PCA9538_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/pca9538.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/irq.h>
#if defined(CONFIG_IOEXPANDER) && defined(CONFIG_IOEXPANDER_PCA9538)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Prerequisites:
* CONFIG_I2C
* I2C support is required
* CONFIG_IOEXPANDER
* Enables support for the PCA9538 I/O expander
*
* CONFIG_IOEXPANDER_PCA9538
* Enables support for the PCA9538 driver (Needs CONFIG_INPUT)
* CONFIG_PCA9538_MULTIPLE
* Can be defined to support multiple PCA9538 devices on board.
* CONFIG_PCA9538_INT_NCALLBACKS
* Maximum number of supported pin interrupt callbacks.
*/
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
# ifndef CONFIG_PCA9538_INT_NCALLBACKS
# define CONFIG_PCA9538_INT_NCALLBACKS 4
# endif
#endif
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
# ifndef CONFIG_SCHED_WORKQUEUE
# error Work queue support required. CONFIG_SCHED_WORKQUEUE must be selected.
# endif
#endif
#undef CONFIG_PCA9538_REFCNT
/* PCA9538 Resources ********************************************************/
#define PCA9538_GPIO_NPINS 8
#ifndef CONFIG_I2C
#error "CONFIG_I2C is required by pca9538"
#endif
#define PCA9538_MAXDEVS 4
/* I2C frequency */
#define PCA9538_I2C_MAXFREQUENCY 400000 /* 400KHz */
/* PCA9538 Registers ********************************************************/
#define PCA9538_REG_INPUT 0x00
#define PCA9538_REG_OUTPUT 0x01
#define PCA9538_REG_POLINV 0x02
#define PCA9538_REG_CONFIG 0x03
/****************************************************************************
* Public Types
****************************************************************************/
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
/* This type represents on registered pin interrupt callback */
struct pca9538_callback_s
{
ioe_pinset_t pinset; /* Set of pin interrupts that will generate
* the callback. */
ioe_callback_t cbfunc; /* The saved callback function pointer */
FAR void *cbarg; /* Callback argument */
};
#endif
/* This structure represents the state of the PCA9538 driver */
struct pca9538_dev_s
{
struct ioexpander_dev_s dev; /* Nested structure to allow casting
* as public gpio expander. */
#ifdef CONFIG_PCA9538_SHADOW_MODE
uint8_t sreg[8]; /* Shadowed registers of the PCA9538 */
#endif
#ifdef CONFIG_PCA9538_MULTIPLE
FAR struct pca9538_dev_s *flink; /* Supports a singly linked list of drivers */
#endif
FAR struct pca9538_config_s *config; /* Board configuration data */
FAR struct i2c_master_s *i2c; /* Saved I2C driver instance */
mutex_t lock; /* Mutual exclusion */
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
struct work_s work; /* Supports the interrupt handling "bottom half" */
/* Saved callback information for each I/O expander client */
struct pca9538_callback_s cb[CONFIG_PCA9538_INT_NCALLBACKS];
#endif
};
#endif /* CONFIG_IOEXPANDER && CONFIG_IOEXPANDER_PCA9538 */
#endif /* __DRIVERS_IOEXPANDER_PCA9538_H */