lupyuen commented on code in PR #16011: URL: https://github.com/apache/nuttx/pull/16011#discussion_r2008513572
########## drivers/analog/ads1115.c: ########## @@ -0,0 +1,827 @@ +/**************************************************************************** + * drivers/analog/ads1115.c + * + * 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. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <nuttx/nuttx.h> +#include <nuttx/signal.h> + +#include <assert.h> +#include <debug.h> +#include <endian.h> +#include <errno.h> +#include <stdbool.h> +#include <stdint.h> +#include <stdio.h> +#include <sys/types.h> + +#include <nuttx/analog/adc.h> +#include <nuttx/analog/ads1115.h> +#include <nuttx/analog/ioctl.h> +#include <nuttx/arch.h> +#include <nuttx/i2c/i2c_master.h> + +/**************************************************************************** + * Preprocessor definitions + ****************************************************************************/ + +#if defined(CONFIG_ADC_ADS1115) + +#ifndef CONFIG_ADC_ADS1115_I2C_FREQUENCY +#define CONFIG_ADC_ADS1115_I2C_FREQUENCY 100000 +#endif + +#define ADS1115_NUM_CHANNELS 8 + +#define ADS1115_OS_SHIFT (1 << 15) +#define ADS1115_MUX_SHIFT 12 +#define ADS1115_MUX_MASK (7 << ADS1115_MUX_SHIFT) +#define ADS1115_PGA_SHIFT 9 +#define ADS1115_PGA_MASK (7 << ADS1115_PGA_SHIFT) +#define ADS1115_MODE_MASK (1 << 8) +#define ADS1115_DR_SHIFT 5 +#define ADS1115_DR_MASK (7 << ADS1115_DR_SHIFT) +#define ADS1115_COMP_MODE_MASK (1 << 4) +#define ADS1115_COMP_POL_MASK (1 << 3) +#define ADS1115_COMP_LAT_MASK (1 << 2) +#define ADS1115_COMP_QUE_SHIFT 0 +#define ADS1115_COMP_QUE_MASK (3 << ADS1115_COMP_QUE_SHIFT) + +/**************************************************************************** + * Private Types + ****************************************************************************/ + +struct ads1115_dev_s +{ + FAR struct i2c_master_s *i2c; + FAR const struct adc_callback_s *cb; + uint8_t addr; + + /* Current configuration of ADC. */ + + uint16_t cmdbyte; +}; + +enum ads1115_registers_e +{ + ADS1115_CONVERSION_REGISTER = 0x00, + ADS1115_CONFIG_REGISTER = 0x01, + ADS1115_LO_THRESH_REGISTER = 0x02, + ADS1115_HI_THRESH_REGISTER = 0x03, +}; + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +static int ads1115_bind(FAR struct adc_dev_s *dev, + FAR const struct adc_callback_s *callback); +static void ads1115_reset(FAR struct adc_dev_s *dev); +static int ads1115_setup(FAR struct adc_dev_s *dev); +static void ads1115_shutdown(FAR struct adc_dev_s *dev); +static void ads1115_rxint(FAR struct adc_dev_s *dev, bool enable); +static int ads1115_ioctl(FAR struct adc_dev_s *dev, int cmd, + unsigned long arg); + +/**************************************************************************** + * Private Data + ****************************************************************************/ + +static const struct adc_ops_s g_ads1115ops = +{ + .ao_bind = ads1115_bind, + .ao_reset = ads1115_reset, + .ao_setup = ads1115_setup, + .ao_shutdown = ads1115_shutdown, + .ao_rxint = ads1115_rxint, + .ao_ioctl = ads1115_ioctl, +}; + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: ads1115_write_register + * + * Description: + * Writes a value to a register in the ADS1115. + * + * Input Parameters: + * priv - An ADS1115 device structure + * reg - The register to write to. + * value - The value to write to the register, in big endian. + * + ****************************************************************************/ + +static int ads1115_write_register(FAR struct ads1115_dev_s *priv, + enum ads1115_registers_e reg, + uint16_t value) +{ + int ret = OK; + + if (priv == NULL) + { + ret = -EINVAL; + } + else + { + struct i2c_msg_s i2cmsg[2]; + + /* Write the register into the address pointer register. */ + + i2cmsg[0].frequency = CONFIG_ADC_ADS1115_I2C_FREQUENCY; + i2cmsg[0].addr = priv->addr; + i2cmsg[0].flags = 0; + i2cmsg[0].buffer = ® + i2cmsg[0].length = sizeof(reg); + + /* Write the value into the register. */ + + i2cmsg[1].frequency = CONFIG_ADC_ADS1115_I2C_FREQUENCY; + i2cmsg[1].addr = priv->addr; + i2cmsg[1].flags = I2C_M_NOSTART; + i2cmsg[1].buffer = (FAR uint8_t *)&value; + i2cmsg[1].length = sizeof(value); + + ret = I2C_TRANSFER(priv->i2c, i2cmsg, 2); + if (ret < 0) + { + aerr("ADS1115 I2C transfer failed: %d\n", ret); + } + } + + return ret; +} + +/**************************************************************************** + * Name: ads1115_read_register + * + * Description: + * Reads a value from a register in the ADS1115 in big endian. + * + * Input Parameters: + * priv - An ADS1115 device structure + * reg - The register to read from. + * buf - A pointer to a buffer to store the value read from the register. + * + ****************************************************************************/ + +static int ads1115_read_register(FAR struct ads1115_dev_s *priv, uint8_t reg, + uint16_t *buf) +{ + int ret = OK; + + if (priv == NULL || buf == NULL) + { + ret = -EINVAL; + } + else + { + struct i2c_msg_s i2cmsg[2]; + + /* Write the register into the address pointer register. */ + + i2cmsg[0].frequency = CONFIG_ADC_ADS1115_I2C_FREQUENCY; + i2cmsg[0].addr = priv->addr; + i2cmsg[0].flags = 0; + i2cmsg[0].buffer = (FAR uint8_t *)(®); + i2cmsg[0].length = sizeof(reg); + + /* Read from the register. */ + + i2cmsg[1].frequency = CONFIG_ADC_ADS1115_I2C_FREQUENCY; + i2cmsg[1].addr = priv->addr; + i2cmsg[1].flags = I2C_M_READ; + i2cmsg[1].buffer = (FAR uint8_t *)(buf); + i2cmsg[1].length = sizeof(*buf); + + ret = I2C_TRANSFER(priv->i2c, i2cmsg, 2); + if (ret < 0) + { + aerr("ADS1115 I2C transfer failed: %d\n", ret); + } + } + + return ret; +} + +/**************************************************************************** + * Name: ads1115_read_current_register + * + * Description: + * Reads from the current register in the ADS1115 in big endian. + * + * Input Parameters: + * priv - An ADS1115 device structure + * buf - A pointer to a buffer to store the value read from the register. + * + ****************************************************************************/ + +static int ads1115_read_current_register(FAR struct ads1115_dev_s *priv, + uint16_t *buf) +{ + int ret = OK; + + if (priv == NULL || buf == NULL) + { + ret = -EINVAL; + } + else + { + struct i2c_msg_s i2cmsg[1]; + + i2cmsg[0].frequency = CONFIG_ADC_ADS1115_I2C_FREQUENCY; + i2cmsg[0].addr = priv->addr; + i2cmsg[0].flags = I2C_M_READ; + i2cmsg[0].buffer = (FAR uint8_t *)(buf); + i2cmsg[0].length = sizeof(*buf); + + ret = I2C_TRANSFER(priv->i2c, i2cmsg, 1); + if (ret < 0) + { + aerr("ADS1115 I2C transfer failed: %d\n", ret); + } + } + + return ret; +} + +/**************************************************************************** + * Name: cmdbyte_init + * + * Description: + * Initializes the command byte with the default settings, and writes to the + * high and low threshold registers. + * + * Input Parameters: + * priv - An ADS1115 device structure + * + ****************************************************************************/ + +static int cmdbyte_init(FAR struct ads1115_dev_s *priv) +{ + int ret = OK; + + /* Set the default channel. */ + + priv->cmdbyte = CONFIG_ADC_ADS1115_CHANNEL << ADS1115_MUX_SHIFT; + + /* Set the default pga setting. */ + + priv->cmdbyte |= CONFIG_ADC_ADS1115_PGA << ADS1115_PGA_SHIFT; + + /* Set the default mode. */ + +#ifndef CONFIG_ADC_ADS1115_CONTINOUS + priv->cmdbyte |= ADS1115_MODE_MASK; +#endif + + /* Set the default data rate. */ + + priv->cmdbyte |= CONFIG_ADC_ADS1115_DR << ADS1115_DR_SHIFT; + + /* Set the default comparator mode. */ + +#ifdef CONFIG_ADC_ADS1115_COMP_MODE + priv->cmdbyte |= ADS1115_COMP_MODE_MASK; +#endif + + /* Set the default comparator polarity. */ + +#ifdef CONFIG_ADC_ADS1115_COMP_POL + priv->cmdbyte |= ADS1115_COMP_POL_MASK; +#endif + + /* Set the default comparator latching. */ + +#ifdef CONFIG_ADC_ADS1115_COMP_LAT + priv->cmdbyte |= ADS1115_COMP_LAT_MASK; +#endif + + /* Set the comparator queue. */ + + priv->cmdbyte |= CONFIG_ADC_ADS1115_COMP_QUE << ADS1115_COMP_QUE_SHIFT; + + ret = ads1115_write_register(priv, ADS1115_HI_THRESH_REGISTER, + htobe16(CONFIG_ADC_ADS1115_HI_THRESH)); + if (ret != OK) + { + aerr("Failed to write high threshold register\n"); + return ret; + } + + ret = ads1115_write_register(priv, ADS1115_LO_THRESH_REGISTER, + htobe16(CONFIG_ADC_ADS1115_LO_THRESH)); + + return ret; +} + +/**************************************************************************** + * Name: ads1115_readchannel + * + * Description: + * Reads a conversion from the ADC. + * + * Input Parameters: + * priv - An ADS1115 device structure + * msg - An ADC message struct where the am_channel member contains the + * channel number to be read, and where the am_data member is where the + * reading is stored. + * + * NOTE: + * When switching between channels in continous mode, old data may be read. + * Using the ALERT/RDY pin can avoid this. + * + * Each channel corrseponds to a differing mux configuration as defined in + * the datasheet. + * + * msg->am_channel MUX Configuration + * 0 AINP = AIN0, AINN = AIN1 + * 1 AINP = AIN0, AINN = AIN3 + * 2 AINP = AIN1, AINN = AIN3 + * 3 AINP = AIN2, AINN = AIN3 + * 4 AINP = AIN0, AINN = GND + * 5 AINP = AIN0, AINN = GND + * 6 AINP = AIN1, AINN = GND + * 7 AINP = AIN2, AINN = GND + * 8 AINP = AIN3, AINN = GND + ****************************************************************************/ + +static int ads1115_readchannel(FAR struct ads1115_dev_s *priv, + FAR struct adc_msg_s *msg) +{ + int ret = OK; + + if (priv == NULL || msg == NULL || msg->am_channel >= ADS1115_NUM_CHANNELS) + { + ret = -EINVAL; + } + else + { + uint16_t buf; + uint16_t channel_bits = msg->am_channel << ADS1115_MUX_SHIFT; + + bool one_shot = + ((priv->cmdbyte & ADS1115_MODE_MASK) == ADS1115_MODE_MASK); + bool new_channel = + ((priv->cmdbyte & ADS1115_MUX_MASK) != channel_bits); + + /* check if our current channel is the same as the one that + * is set or if in one shot mode. + */ + + if (new_channel || one_shot) + { + /* Clear the current mux bits. */ + + priv->cmdbyte &= ~(ADS1115_MUX_MASK); + + /* Set the new mux bits. */ + + priv->cmdbyte |= channel_bits; + + /* Set the OS bit to start conversion. */ + + priv->cmdbyte |= ADS1115_OS_SHIFT; + + /* Write to the configuration register. */ + + ainfo("cmdbyte: %x\n", priv->cmdbyte); + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + + if (one_shot) + { + /* Read the configuration register until OS has been set to 1. */ + + int count = 0; + do + { + /* ADS1115 takes ~25 usec to wake up */ + + nxsig_usleep(25); + ret = ads1115_read_current_register(priv, &buf); + count++; + } + while ((be16toh(buf) & ADS1115_OS_SHIFT) == 0 && ret == OK && + count < 3); + ainfo("config register: %x\n", (be16toh(buf))); + + if (count >= 3) + { + aerr("ADS1115 timed out waiting for conversion to finish\n"); + return -ETIMEDOUT; + } + } + + /* Read the conversion register. */ + + ret = ads1115_read_register(priv, ADS1115_CONVERSION_REGISTER, &buf); + ainfo("output: %d\n", (int16_t)betoh16(buf)); + msg->am_data = (uint32_t)betoh16(buf); + + priv->cmdbyte &= ~(ADS1115_OS_SHIFT); /* Clear the OS bit. */ + } + + return ret; +} + +/**************************************************************************** + * Name: ads1115_bind + * + * Description: + * Bind the upper-half driver callbacks to the lower-half implementation. + * This must be called early in order to receive ADC event notifications. + * + ****************************************************************************/ + +static int ads1115_bind(FAR struct adc_dev_s *dev, + FAR const struct adc_callback_s *callback) +{ + FAR struct ads1115_dev_s *priv = (FAR struct ads1115_dev_s *)dev->ad_priv; + + DEBUGASSERT(priv != NULL); + priv->cb = callback; + return 0; +} + +/**************************************************************************** + * Name: ads1115_reset + * + * Description: + * Reset the ADC device. Called early to initialize the hardware. This + * is called, before ao_setup() and on error conditions. + * + ****************************************************************************/ + +static void ads1115_reset(FAR struct adc_dev_s *dev) +{ + FAR struct ads1115_dev_s *priv = (FAR struct ads1115_dev_s *)dev->ad_priv; + + cmdbyte_init(priv); +} + +/**************************************************************************** + * Name: ads1115_setup + * + * Description: + * Configure the ADC. This method is called the first time that the ADC + * device is opened. This method will write the default configuration into + * the configuration register. + * + ****************************************************************************/ + +static int ads1115_setup(FAR struct adc_dev_s *dev) +{ + FAR struct ads1115_dev_s *priv = (FAR struct ads1115_dev_s *)dev->ad_priv; + + int ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + return ret; +} + +/**************************************************************************** + * Name: ads1115_shutdown + * + * Description: + * Disable the ADC. This method is called when the ADC device is closed. + * This method should reverse the operation of the setup method. The + * ADS1115 can be put into a power-down state by setting the mode bit to + * single-shot. This will stop the ADC from converting and reduce power + * consumption. + * + ****************************************************************************/ + +static void ads1115_shutdown(FAR struct adc_dev_s *dev) +{ + FAR struct ads1115_dev_s *priv = (FAR struct ads1115_dev_s *)dev->ad_priv; + + priv->cmdbyte |= ADS1115_MODE_MASK; + ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); +} + +/**************************************************************************** + * Name: ads1115_rxint + * + * Description: + * Needed for ADC upper-half compatibility but conversion interrupts + * are not supported by the ADS1115. + * + ****************************************************************************/ + +static void ads1115_rxint(FAR struct adc_dev_s *dev, bool enable) +{ +} + +/**************************************************************************** + * Name: ads1115_ioctl + * + * Description: + * All ioctl calls will be routed through this method. + * + ****************************************************************************/ + +static int ads1115_ioctl(FAR struct adc_dev_s *dev, int cmd, + unsigned long arg) +{ + FAR struct ads1115_dev_s *priv = (FAR struct ads1115_dev_s *)dev->ad_priv; + int ret = OK; + + switch (cmd) + { + case ANIOC_TRIGGER: + { + struct adc_msg_s msg; + + for (uint8_t i = 0; i < ADS1115_NUM_CHANNELS && (ret == 0); i++) + { + msg.am_channel = i; + ainfo("Channel: %d\n", i); + ret = ads1115_readchannel(priv, &msg); + if (ret == 0) + { + priv->cb->au_receive(dev, i, msg.am_data); + } + else + { + aerr("Error reading channel %d with error %d \n", i, ret); + } + } + } + break; + + case ANIOC_ADS1115_SET_PGA: + { + if (arg >= ADS1115_PGA1 && arg <= ADS1115_PGA8) + { + priv->cmdbyte &= ~ADS1115_PGA_MASK; + priv->cmdbyte |= arg << ADS1115_PGA_SHIFT; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_SET_MODE: + { + if (arg == ADS1115_MODE1) + { + priv->cmdbyte &= ~ADS1115_MODE_MASK; + } + else if (arg == ADS1115_MODE2) + { + priv->cmdbyte |= ADS1115_MODE_MASK; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_SET_DR: + { + if (arg >= ADS1115_DR1 && arg <= ADS1115_DR8) + { + priv->cmdbyte &= ~ADS1115_DR_MASK; + priv->cmdbyte |= arg << ADS1115_DR_SHIFT; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_SET_COMP_POL: + { + if (arg == ADS1115_COMP_POL1) + { + priv->cmdbyte &= ~ADS1115_COMP_POL_MASK; + } + else if (arg == ADS1115_COMP_POL2) + { + priv->cmdbyte |= ADS1115_COMP_POL_MASK; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_SET_COMP_MODE: + { + if (arg == ADS1115_COMP_MODE1) + { + priv->cmdbyte &= ~ADS1115_COMP_MODE_MASK; + } + else if (arg == ADS1115_COMP_MODE2) + { + priv->cmdbyte |= ADS1115_COMP_MODE_MASK; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_SET_COMP_LAT: + { + if (arg == ADS1115_COMP_LAT1) + { + priv->cmdbyte &= ~ADS1115_COMP_LAT_MASK; + } + else if (arg == ADS1115_COMP_LAT2) + { + priv->cmdbyte |= ADS1115_COMP_LAT_MASK; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_SET_COMP_QUEUE: + { + if (arg >= ADS1115_COMP_QUEUE1 && arg <= ADS1115_COMP_QUEUE4) + { + priv->cmdbyte &= ~ADS1115_COMP_QUE_MASK; + priv->cmdbyte |= arg << ADS1115_COMP_QUE_SHIFT; + } + else + { + ret = -EINVAL; + break; + } + + ret = ads1115_write_register(priv, ADS1115_CONFIG_REGISTER, + htobe16(priv->cmdbyte)); + } + break; + + case ANIOC_ADS1115_READ_CHANNEL: + { + FAR struct adc_msg_s *msg = (FAR struct adc_msg_s *)arg; + ret = ads1115_readchannel(priv, msg); + } + break; + + case ANIOC_ADS1115_SET_HI_THRESH: + { + if (arg >= 0 && arg <= UINT16_MAX) + { + ret = ads1115_write_register(priv, ADS1115_HI_THRESH_REGISTER, + htobe16(arg)); + } + else + { + ret = -EINVAL; + } + } + break; + + case ANIOC_ADS1115_SET_LO_THRESH: + { + if (arg >= 0 && arg <= UINT16_MAX) + { + ret = ads1115_write_register(priv, ADS1115_LO_THRESH_REGISTER, + htobe16(arg)); + } + else + { + ret = -EINVAL; + } + } + break; + + case ANIOC_GET_NCHANNELS: + { + ret = ADS1115_NUM_CHANNELS; + } + break; + + default: + ret = -ENOTTY; + break; + } + + return ret; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: ads1115_initialize + * + * Description: + * Initialize the selected ADC + * + * Input Parameters: + * i2c - Pointer to a valid I2C master struct. + * addr - I2C device address. + * + * Returned Value: + * Valid ADC device structure reference on success; a NULL on failure + * + * **************************************************************************/ + +FAR struct adc_dev_s *ads1115_initialize(FAR struct i2c_master_s *i2c, + uint8_t addr) +{ + FAR struct ads1115_dev_s *priv; + FAR struct adc_dev_s *adcdev; + + DEBUGASSERT(i2c != NULL); + + priv = kmm_malloc(sizeof(struct ads1115_dev_s)); + if (priv == NULL) + { + aerr("ERROR: Failed to allocate ads1115_dev_s instance\n"); + free(priv); + return NULL; + } + + priv->cb = NULL; + priv->i2c = i2c; + priv->addr = addr; + priv->cmdbyte = 0; + + int ret = cmdbyte_init(priv); + if (ret != OK) + { + aerr("Failed to initialize ADS1115\n"); + free(priv); + return NULL; + } + + adcdev = kmm_malloc(sizeof(struct adc_dev_s)); + if (adcdev == NULL) + { + aerr("ERROR: Failed to allocate adc_dev_s instance\n"); + return NULL; + } + + memset(adcdev, 0, sizeof(struct adc_dev_s)); + adcdev->ad_ops = &g_ads1115ops; + adcdev->ad_priv = priv; + + return adcdev; +} + +#endif /* CONFIG_ADC_ADS1115 */ Review Comment: I suggest we add a newline after `#endif`. Thanks :-) -- 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: commits-unsubscr...@nuttx.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
