incubator-nuttx/include/nuttx/ioexpander/mcp23x17.h

111 lines
3.8 KiB
C

/****************************************************************************
* include/nuttx/ioexpander/mcp23x17.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_MCP23X17_H
#define __INCLUDE_NUTTX_IOEXPANDER_MCP23X17_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 mcp23x17
* driver when the driver is instantiated. This structure provides
* information about the configuration of the mcp23x17 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 mcp23x17_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 MCP23X17's nReset pin */
CODE void (*set_nreset_pin)(bool state);
#ifdef CONFIG_IOEXPANDER_INT_ENABLE
/* If multiple mcp23x17 devices are supported, then an IRQ number must
* be provided for each so that their interrupts can be distinguished.
*/
/* IRQ/GPIO access callbacks. These operations all hidden behind
* callbacks to isolate the mcp23x17 driver from differences in GPIO
* interrupt handling by varying boards and MCUs.
*
* attach - Attach the mcp23x17 interrupt handler to the GPIO interrupt
* enable - Enable or disable the GPIO interrupt
*/
CODE int (*attach)(FAR struct mcp23x17_config_s *state, xcpt_t isr,
FAR void *arg);
CODE void (*enable)(FAR struct mcp23x17_config_s *state, bool enable);
#endif
};
/****************************************************************************
* Public Function Prototypes
****************************************************************************/
#ifdef __cplusplus
#define EXTERN extern "C"
extern "C"
{
#else
#define EXTERN extern
#endif
/****************************************************************************
* Name: mcp23x17_initialize
*
* Description:
* Initialize a MCP23X17 I2C device.
*
* TODO: Add support for more than one device.
*
****************************************************************************/
FAR struct ioexpander_dev_s *mcp23x17_initialize(
FAR struct i2c_master_s *i2cdev,
FAR struct mcp23x17_config_s *config);
#ifdef __cplusplus
}
#endif
#endif /* __INCLUDE_NUTTX_IOEXPANDER_MCP23X17_H */