blob: edbae36094ab800f72c71a5af8a97ba99ac41fcd [file] [log] [blame]
/*
* Copyright (c) 2018 Alexander Wachter.
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT ams_ens210
#include <zephyr/device.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/kernel.h>
#include <zephyr/sys/byteorder.h>
#include <zephyr/sys/util.h>
#include <zephyr/drivers/sensor.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/logging/log.h>
#include "ens210.h"
LOG_MODULE_REGISTER(ENS210, CONFIG_SENSOR_LOG_LEVEL);
#ifdef CONFIG_ENS210_CRC_CHECK
static uint32_t ens210_crc7(uint32_t bitstream)
{
uint32_t polynomial = (ENS210_CRC7_POLY << (ENS210_CRC7_DATA_WIDTH - 1));
uint32_t bit = ENS210_CRC7_DATA_MSB << ENS210_CRC7_WIDTH;
uint32_t val = (bitstream << ENS210_CRC7_WIDTH) | ENS210_CRC7_IVEC;
while (bit & (ENS210_CRC7_DATA_MASK << ENS210_CRC7_WIDTH)) {
if (bit & val) {
val ^= polynomial;
}
bit >>= 1;
polynomial >>= 1;
}
return val;
}
#endif /* CONFIG_ENS210_CRC_CHECK */
#if defined(CONFIG_ENS210_TEMPERATURE_SINGLE) \
|| defined(CONFIG_ENS210_HUMIDITY_SINGLE)
static int ens210_measure(const struct device *i2c_dev,
enum sensor_channel chan)
{
uint8_t buf;
int ret;
const struct ens210_sens_start sense_start = {
.t_start = ENS210_T_START && (chan == SENSOR_CHAN_ALL
|| chan == SENSOR_CHAN_AMBIENT_TEMP),
.h_start = ENS210_H_START && (chan == SENSOR_CHAN_ALL
|| chan == SENSOR_CHAN_HUMIDITY)
};
/* Start measuring */
ret = i2c_reg_write_byte(i2c_dev,
DT_INST_REG_ADDR(0),
ENS210_REG_SENS_START, *(uint8_t *)&sense_start);
if (ret < 0) {
LOG_ERR("Failed to set SENS_START to 0x%x",
*(uint8_t *)&sense_start);
return -EIO;
}
/* Wait for measurement to be completed */
do {
k_sleep(K_MSEC(2));
ret = i2c_reg_read_byte(i2c_dev,
DT_INST_REG_ADDR(0),
ENS210_REG_SENS_START, &buf);
if (ret < 0) {
LOG_ERR("Failed to read SENS_STAT");
}
} while (buf & *(uint8_t *)&sense_start);
return ret;
}
#endif /* Single shot mode */
static int ens210_sample_fetch(const struct device *dev,
enum sensor_channel chan)
{
struct ens210_data *drv_data = dev->data;
struct ens210_value_data data[2];
int ret, cnt;
#ifdef CONFIG_ENS210_CRC_CHECK
uint32_t temp_valid, humidity_valid;
#endif /* CONFIG_ENS210_CRC_CHECK */
__ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL
|| chan == SENSOR_CHAN_AMBIENT_TEMP
|| chan == SENSOR_CHAN_HUMIDITY);
#if defined(CONFIG_ENS210_TEMPERATURE_SINGLE) \
|| defined(CONFIG_ENS210_HUMIDITY_SINGLE)
ret = ens210_measure(drv_data->i2c, chan);
if (ret < 0) {
LOG_ERR("Failed to measure");
return ret;
}
#endif /* Single shot mode */
for (cnt = 0; cnt <= CONFIG_ENS210_MAX_READ_RETRIES; cnt++) {
ret = i2c_burst_read(drv_data->i2c, DT_INST_REG_ADDR(0),
ENS210_REG_T_VAL, (uint8_t *)&data, sizeof(data));
if (ret < 0) {
LOG_ERR("Failed to read data");
continue;
}
/* Get temperature value */
if (chan == SENSOR_CHAN_ALL || chan == SENSOR_CHAN_AMBIENT_TEMP) {
if (!data[0].valid) {
LOG_WRN("Temperature not valid");
continue;
}
#ifdef CONFIG_ENS210_CRC_CHECK
temp_valid = data[0].val |
(data[0].valid << (sizeof(data[0].val) * 8));
if (ens210_crc7(temp_valid) != data[0].crc7) {
LOG_WRN("Temperature CRC error");
continue;
}
#endif /* CONFIG_ENS210_CRC_CHECK */
drv_data->temp = data[0];
}
/* Get humidity value */
if (chan == SENSOR_CHAN_ALL || chan == SENSOR_CHAN_HUMIDITY) {
if (!data[1].valid) {
LOG_WRN("Humidity not valid");
continue;
}
#ifdef CONFIG_ENS210_CRC_CHECK
humidity_valid = data[1].val |
(data[1].valid << (sizeof(data[1].val) * 8));
if (ens210_crc7(humidity_valid) != data[1].crc7) {
LOG_WRN("Humidity CRC error");
continue;
}
#endif /* CONFIG_ENS210_CRC_CHECK */
drv_data->humidity = data[1];
}
return 0;
}
return -EIO;
}
static int ens210_channel_get(const struct device *dev,
enum sensor_channel chan,
struct sensor_value *val)
{
struct ens210_data *drv_data = dev->data;
int32_t temp_frac;
int32_t humidity_frac;
switch (chan) {
case SENSOR_CHAN_AMBIENT_TEMP:
/* Temperature is in 1/64 Kelvin. Subtract 273.15 for Celsius */
temp_frac = sys_le16_to_cpu(drv_data->temp.val) * (1000000 / 64);
temp_frac -= 273150000;
val->val1 = temp_frac / 1000000;
val->val2 = temp_frac % 1000000;
break;
case SENSOR_CHAN_HUMIDITY:
humidity_frac = sys_le16_to_cpu(drv_data->humidity.val) *
(1000000 / 512);
val->val1 = humidity_frac / 1000000;
val->val2 = humidity_frac % 1000000;
break;
default:
return -ENOTSUP;
}
return 0;
}
static int ens210_sys_reset(const struct device *i2c_dev)
{
const struct ens210_sys_ctrl sys_ctrl = {
.low_power = 0,
.reset = 1
};
int ret;
ret = i2c_reg_write_byte(i2c_dev, DT_INST_REG_ADDR(0),
ENS210_REG_SYS_CTRL, *(uint8_t *)&sys_ctrl);
if (ret < 0) {
LOG_ERR("Failed to set SYS_CTRL to 0x%x", *(uint8_t *)&sys_ctrl);
}
return ret;
}
static int ens210_sys_enable(const struct device *i2c_dev, uint8_t low_power)
{
const struct ens210_sys_ctrl sys_ctrl = {
.low_power = low_power,
.reset = 0
};
int ret;
ret = i2c_reg_write_byte(i2c_dev, DT_INST_REG_ADDR(0),
ENS210_REG_SYS_CTRL, *(uint8_t *)&sys_ctrl);
if (ret < 0) {
LOG_ERR("Failed to set SYS_CTRL to 0x%x", *(uint8_t *)&sys_ctrl);
}
return ret;
}
static int ens210_wait_boot(const struct device *i2c_dev)
{
int cnt;
int ret;
struct ens210_sys_stat sys_stat;
for (cnt = 0; cnt <= CONFIG_ENS210_MAX_STAT_RETRIES; cnt++) {
ret = i2c_reg_read_byte(i2c_dev, DT_INST_REG_ADDR(0),
ENS210_REG_SYS_STAT,
(uint8_t *)&sys_stat);
if (ret < 0) {
k_sleep(K_MSEC(1));
continue;
}
if (sys_stat.sys_active) {
return 0;
}
if (cnt == 0) {
ens210_sys_reset(i2c_dev);
}
ens210_sys_enable(i2c_dev, 0);
k_sleep(K_MSEC(2));
}
if (ret < 0) {
LOG_ERR("Failed to read SYS_STATE");
}
LOG_ERR("Sensor is not in active state");
return -EIO;
}
static const struct sensor_driver_api en210_driver_api = {
.sample_fetch = ens210_sample_fetch,
.channel_get = ens210_channel_get,
};
static int ens210_init(const struct device *dev)
{
struct ens210_data *drv_data = dev->data;
const struct ens210_sens_run sense_run = {
.t_run = ENS210_T_RUN,
.h_run = ENS210_H_RUN
};
#if defined(CONFIG_ENS210_TEMPERATURE_CONTINUOUS) \
|| defined(CONFIG_ENS210_HUMIDITY_CONTINUOUS)
const struct ens210_sens_start sense_start = {
.t_start = ENS210_T_RUN,
.h_start = ENS210_H_RUN
};
#endif
int ret;
uint16_t part_id;
drv_data->i2c = device_get_binding(DT_INST_BUS_LABEL(0));
if (drv_data->i2c == NULL) {
LOG_ERR("Failed to get pointer to %s device!",
DT_INST_BUS_LABEL(0));
return -EINVAL;
}
/* Wait until the device is ready. */
ret = ens210_wait_boot(drv_data->i2c);
if (ret < 0) {
return -EIO;
}
/* Check Hardware ID. This is only possible after device is ready
* and active
*/
ret = i2c_burst_read(drv_data->i2c, DT_INST_REG_ADDR(0),
ENS210_REG_PART_ID, (uint8_t *)&part_id,
sizeof(part_id));
if (ret < 0) {
LOG_ERR("Failed to read Part ID register");
return -EIO;
}
if (part_id != ENS210_PART_ID) {
LOG_ERR("Part ID does not match. Want 0x%x, got 0x%x",
ENS210_PART_ID, part_id);
return -EIO;
}
/* Enable low power mode */
if ((ENS210_T_RUN | ENS210_H_RUN) == 0) {
ens210_sys_enable(drv_data->i2c, 1);
}
/* Set measurement mode*/
ret = i2c_reg_write_byte(drv_data->i2c, DT_INST_REG_ADDR(0),
ENS210_REG_SENS_RUN, *(uint8_t *)&sense_run);
if (ret < 0) {
LOG_ERR("Failed to set SENS_RUN to 0x%x",
*(uint8_t *)&sense_run);
return -EIO;
}
#if defined(CONFIG_ENS210_TEMPERATURE_CONTINUOUS) \
|| defined(CONFIG_ENS210_HUMIDITY_CONTINUOUS)
/* Start measuring */
ret = i2c_reg_write_byte(drv_data->i2c, DT_INST_REG_ADDR(0),
ENS210_REG_SENS_START, *(uint8_t *)&sense_start);
if (ret < 0) {
LOG_ERR("Failed to set SENS_START to 0x%x",
*(uint8_t *)&sense_start);
return -EIO;
}
#endif
return 0;
}
static struct ens210_data ens210_driver;
DEVICE_DT_INST_DEFINE(0, ens210_init, NULL, &ens210_driver,
NULL, POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY,
&en210_driver_api);