raiden00pl commented on code in PR #19736: URL: https://github.com/apache/nuttx/pull/19736#discussion_r3740189524
########## include/nuttx/analog/pot.h: ########## @@ -0,0 +1,244 @@ +/**************************************************************************** + * include/nuttx/analog/pot.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_ANALOG_POT_H +#define __INCLUDE_NUTTX_ANALOG_POT_H + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <nuttx/compiler.h> +#include <nuttx/analog/ioctl.h> +#include <nuttx/mutex.h> + +#include <stdbool.h> +#include <stdint.h> + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/* IOCTL Commands ***********************************************************/ + +/* Common IOCTL commands for all digital potentiometer drivers. Optional + * commands return -ENOTSUP if not implemented by the lower half; support + * is advertised in pot_info_s caps. + * + * Cmd: POTIOC_GET_INFO Arg: struct pot_info_s *info + * Cmd: POTIOC_SET_WIPER Arg: struct pot_wiper_s *wiper + * Cmd: POTIOC_GET_WIPER Arg: struct pot_wiper_s *wiper + * Cmd: POTIOC_MOVE_WIPER Arg: struct pot_move_s *move + * Cmd: POTIOC_SET_ENABLE Arg: struct pot_enable_s *enable + * Cmd: POTIOC_STORE_WIPER Arg: struct pot_nv_s *nv + * Cmd: POTIOC_RECALL_WIPER Arg: struct pot_nv_s *nv + */ + +#define POTIOC_GET_INFO _ANIOC(AN_POT_FIRST + 0) +#define POTIOC_SET_WIPER _ANIOC(AN_POT_FIRST + 1) +#define POTIOC_GET_WIPER _ANIOC(AN_POT_FIRST + 2) +#define POTIOC_MOVE_WIPER _ANIOC(AN_POT_FIRST + 3) +#define POTIOC_SET_ENABLE _ANIOC(AN_POT_FIRST + 4) +#define POTIOC_STORE_WIPER _ANIOC(AN_POT_FIRST + 5) +#define POTIOC_RECALL_WIPER _ANIOC(AN_POT_FIRST + 6) + +/* Device capabilities reported in pot_info_s */ + +#define POT_CAP_READBACK (1 << 0) /* Wiper position can be read back */ +#define POT_CAP_MOVE (1 << 1) /* Relative wiper move supported */ +#define POT_CAP_ENABLE (1 << 2) /* Wiper enable/shutdown supported */ +#define POT_CAP_NV (1 << 3) /* Non-volatile store/recall supported */ + +/**************************************************************************** + * Public Types + ****************************************************************************/ + +/* Device properties for POTIOC_GET_INFO */ + +struct pot_info_s +{ + uint8_t nwipers; /* Number of wipers */ + uint32_t max; /* Wiper full scale position */ + uint32_t rab; /* Terminal A-B resistance in ohms, + * 0 if unknown. ohms = val * rab / max */ + uint32_t caps; /* Capabilities, see POT_CAP_* */ +}; + +/* Wiper access for POTIOC_SET_WIPER and POTIOC_GET_WIPER */ + +struct pot_wiper_s +{ + uint8_t wiper; /* Wiper index */ + uint32_t val; /* Wiper value */ +}; + +/* Relative wiper move for POTIOC_MOVE_WIPER */ + +struct pot_move_s +{ + uint8_t wiper; /* Wiper index */ + int32_t steps; /* Steps to move, negative moves down */ +}; + +/* Wiper enable control for POTIOC_SET_ENABLE */ + +struct pot_enable_s +{ + uint8_t wiper; /* Wiper index */ + bool enable; /* false forces wiper into shutdown */ +}; + +/* Non-volatile transfer for POTIOC_STORE_WIPER and POTIOC_RECALL_WIPER */ + +struct pot_nv_s +{ + uint8_t wiper; /* Wiper index */ + uint8_t slot; /* Non-volatile slot index */ +}; + +struct pot_dev_s; +struct pot_ops_s +{ + /* Configure the potentiometer. This method is called the first time + * that the potentiometer device is opened. + */ + + CODE int (*po_setup)(FAR struct pot_dev_s *dev); + + /* Disable the potentiometer. This method is called when the + * potentiometer device is closed. This method reverses the operation + * of the setup method. + */ + + CODE void (*po_shutdown)(FAR struct pot_dev_s *dev); + + /* Set a wiper value. Optional. */ + + CODE int (*po_setwiper)(FAR struct pot_dev_s *dev, uint8_t wiper, + uint32_t val); + + /* Get a wiper value. Optional. */ + + CODE int (*po_getwiper)(FAR struct pot_dev_s *dev, uint8_t wiper, + FAR uint32_t *val); + + /* Move a wiper by a number of steps, negative moves down. Optional. */ + + CODE int (*po_move)(FAR struct pot_dev_s *dev, uint8_t wiper, + int32_t steps); + + /* Enable or force a wiper into shutdown. Optional. */ + + CODE int (*po_enable)(FAR struct pot_dev_s *dev, uint8_t wiper, + bool enable); + + /* Store a wiper value to a non-volatile slot. Optional. */ + + CODE int (*po_store)(FAR struct pot_dev_s *dev, uint8_t wiper, + uint8_t slot); + + /* Recall a wiper value from a non-volatile slot. Optional. */ + + CODE int (*po_recall)(FAR struct pot_dev_s *dev, uint8_t wiper, + uint8_t slot); + + /* Lower-half logic may support chip-specific ioctl commands */ + + CODE int (*po_ioctl)(FAR struct pot_dev_s *dev, int cmd, + unsigned long arg); +}; + +struct pot_dev_s +{ + /* Fields managed by common upper half potentiometer logic */ + + uint8_t pd_ocount; /* The number of times the device + * has been opened */ + mutex_t pd_closelock; /* Locks out new opens while close + * is in progress */ + mutex_t pd_lock; /* Serializes ioctl access */ + + /* Fields provided by lower half potentiometer logic */ + + uint8_t pd_nwipers; /* Number of wipers */ + uint32_t pd_max; /* Wiper full scale value */ + uint32_t pd_rab; /* A-B resistance in ohms, + * 0 if unknown */ + FAR const struct pot_ops_s *pd_ops; /* Arch-specific operations */ + FAR void *pd_priv; /* Used by the arch-specific + * logic */ +}; + +/**************************************************************************** + * Public Function Prototypes + ****************************************************************************/ + +#if defined(__cplusplus) +extern "C" +{ +#endif + +/**************************************************************************** + * Name: pot_register + * + * Description: + * Register a digital potentiometer driver. + * + * Input Parameters: + * path - The full path to the driver to register, e.g. "/dev/pot0" + * dev - An instance of the device-specific potentiometer interface + * + * Returned Value: + * Zero on success; a negated errno value on failure. + * + ****************************************************************************/ + +int pot_register(FAR const char *path, FAR struct pot_dev_s *dev); + +/**************************************************************************** + * Name: mcp445x_initialize + * + * Description: + * Initialize a MCP445X potentiometer. + * + * Input Parameters: + * i2c - An instance of the I2C interface to communicate with the device + * addr - The I2C address of the MCP445X + * rab - Terminal A-B resistance in ohms, 0 if unknown + * + * Returned Value: + * Valid MCP445X device structure reference on success; a NULL on failure + * + ****************************************************************************/ + +#ifdef CONFIG_POT_MCP445X +struct i2c_master_s; +FAR struct pot_dev_s *mcp445x_initialize(FAR struct i2c_master_s *i2c, + uint8_t addr, uint32_t rab); +#endif Review Comment: That's not entirely true. There is no common approach in analog drivers. Maybe this is a good opportunity to decide how it should be and change everything in separate PR at once. -- 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]
