xiaoxiang781216 commented on code in PR #15612: URL: https://github.com/apache/nuttx/pull/15612#discussion_r1922005750
########## include/nuttx/ioexpander/mcp23x08.h: ########## @@ -0,0 +1,110 @@ +/**************************************************************************** + * include/nuttx/ioexpander/mcp23x08.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_MCP23X08_H +#define __INCLUDE_NUTTX_IOEXPANDER_MCP23X08_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 mcp23x08 + * driver when the driver is instantiated. This structure provides + * information about the configuration of the mcp23x08 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 mcp23x08_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 MCP23X08's nReset pin */ + + CODE void (*set_nreset_pin)(bool state); + +#ifdef CONFIG_IOEXPANDER_INT_ENABLE + /* If multiple mcp23x08 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 mcp23x08 driver from differences in GPIO + * interrupt handling by varying boards and MCUs. + * + * attach - Attach the mcp23x08 interrupt handler to the GPIO interrupt + * enable - Enable or disable the GPIO interrupt + */ + + CODE int (*attach)(FAR struct mcp23x08_config_s *state, xcpt_t isr, + FAR void *arg); + CODE void (*enable)(FAR struct mcp23x08_config_s *state, bool enable); +#endif +}; + +/**************************************************************************** + * Public Function Prototypes + ****************************************************************************/ + +#ifdef __cplusplus +#define EXTERN extern "C" +extern "C" +{ +#else +#define EXTERN extern +#endif + +/**************************************************************************** + * Name: mcp23x08_initialize + * + * Description: + * Initialize a MCP23X08 I2C device. + * + * TODO: Add support for more than one device. + * + ****************************************************************************/ + +FAR struct ioexpander_dev_s *mcp23x08_initialize( + FAR struct i2c_master_s *i2cdev, + FAR struct mcp23x08_config_s *config); Review Comment: ```suggestion FAR const struct mcp23x08_config_s *config); ``` -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
