incubator-nuttx/drivers/ioexpander/mcp23x08.h

167 lines
6.0 KiB
C

/****************************************************************************
* drivers/ioexpander/mcp23x08.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_MCP23X08_H
#define __DRIVERS_IOEXPANDER_MCP23X08_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/mcp23x08.h>
#include <nuttx/i2c/i2c_master.h>
#include <nuttx/irq.h>
#if defined(CONFIG_IOEXPANDER) && defined(CONFIG_IOEXPANDER_MCP23X08)
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Configuration ************************************************************/
/* Prerequisites:
* CONFIG_I2C
* I2C support is required
* CONFIG_IOEXPANDER
* Enables I/O expander support
*
* CONFIG_IOEXPANDER_MCP23X08
* Enables support for the MCP23X08 driver (Needs CONFIG_INPUT)
* CONFIG_MCP23X08_MULTIPLE
* Can be defined to support multiple MCP23X08 devices on board.
* CONFIG_MCP23X08_INT_NCALLBACKS
* Maximum number of supported pin interrupt callbacks.
* CONFIG_MCP23X08_INT_POLL
* Enables a poll for missed interrupts
* CONFIG_MCP23X08_INT_POLLDELAY
* If CONFIG_MCP23X08_INT_POLL=y, then this is the delay in microseconds
* between polls for missed interrupts.
*/
#ifndef CONFIG_I2C
# error "CONFIG_I2C is required by MCP23X08"
#endif
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
# ifndef CONFIG_MCP23X08_INT_NCALLBACKS
# define CONFIG_MCP23X08_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
#ifndef CONFIG_MCP23X08_INT_POLLDELAY
# define CONFIG_MCP23X08_INT_POLLDELAY 500000
#endif
/* MCP23X08 Definitions *****************************************************/
/* I2C frequency */
#define MCP23X08_I2C_MAXFREQUENCY 400000 /* 400KHz */
/* MCP23X08 *****************************************************************/
/* If IOCON.BANK = 0 Addressing Mode */
#define MCP23X08_IODIR 0x00
#define MCP23X08_IPOL 0x01
#define MCP23X08_GPINTEN 0x02
#define MCP23X08_DEFVAL 0x03
#define MCP23X08_INTCON 0x04
#define MCP23X08_IOCON 0x05
#define MCP23X08_GPPU 0x06
#define MCP23X08_INTF 0x07
#define MCP23X08_INTCAP 0x08
#define MCP23X08_GPIO 0x09
#define MCP23X08_OLAT 0x0a
#define MCP23X08_IOCON_INTPOL (1 << 1) /* Polarity of INT output pin */
#define MCP23X08_IOCON_ODR (1 << 2) /* Config INT pin as open-drain */
#define MCP23X08_IOCON_HAEN (1 << 3) /* HW Address enable bit */
#define MCP23X08_IOCON_DISSLW (1 << 4) /* Disable Slew Rate for SDA output */
#define MCP23X08_IOCON_SEQOP (1 << 5) /* Disable Sequential Operation */
#define MCP23X08_NR_GPIO_MAX 8
#define MCP23X08_POLLDELAY (CONFIG_MCP23X08_INT_POLLDELAY / USEC_PER_TICK)
/****************************************************************************
* Public Types
****************************************************************************/
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
/* This type represents on registered pin interrupt callback */
struct mcp23x08_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 MCP23X08 driver */
struct mcp23x08_dev_s
{
struct ioexpander_dev_s dev; /* Nested structure to allow casting
* as public gpio expander.
*/
#ifdef CONFIG_MCP23X08_MULTIPLE
FAR struct mcp23x08_dev_s *flink; /* Supports a singly linked list of drivers */
#endif
FAR struct mcp23x08_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
#ifdef CONFIG_MCP23X08_INT_POLL
struct wdog_s wdog; /* Timer used to poll for missed interrupts */
#endif
ioe_pinset_t input; /* Last input registers */
ioe_pinset_t intstat; /* Pending interrupts */
struct work_s work; /* Supports the interrupt handling "bottom half" */
/* Saved callback information for each I/O expander client */
struct mcp23x08_callback_s cb[CONFIG_MCP23X08_INT_NCALLBACKS];
#endif
};
#endif /* CONFIG_IOEXPANDER && CONFIG_IOEXPANDER_MCP23X08 */
#endif /* __DRIVERS_IOEXPANDER_MCP23X08_H */