sensor: Add Silabs SI7055 support

Add support for the Silabs SI7055 temperature sensor

Signed-off-by: Greg Leach <greg.leach@lairdconnect.com>
This commit is contained in:
Greg Leach 2020-07-16 19:07:15 +01:00 committed by Maureen Helm
commit 41da0769c1
8 changed files with 219 additions and 0 deletions

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@ -61,6 +61,7 @@ add_subdirectory_ifdef(CONFIG_QDEC_NRFX qdec_nrfx)
add_subdirectory_ifdef(CONFIG_TEMP_NRF5 nrf5)
add_subdirectory_ifdef(CONFIG_SHT3XD sht3xd)
add_subdirectory_ifdef(CONFIG_SI7006 si7006)
add_subdirectory_ifdef(CONFIG_SI7055 si7055)
add_subdirectory_ifdef(CONFIG_SI7060 si7060)
add_subdirectory_ifdef(CONFIG_STTS751 stts751)
add_subdirectory_ifdef(CONFIG_SX9500 sx9500)

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@ -161,6 +161,8 @@ source "drivers/sensor/sht3xd/Kconfig"
source "drivers/sensor/si7006/Kconfig"
source "drivers/sensor/si7055/Kconfig"
source "drivers/sensor/si7060/Kconfig"
source "drivers/sensor/stts751/Kconfig"

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@ -0,0 +1,5 @@
# SPDX-License-Identifier: Apache-2.0
zephyr_library()
zephyr_library_sources_ifdef(CONFIG_SI7055 si7055.c)

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@ -0,0 +1,18 @@
# Copyright (c) 2019 Electronut Labs
# Copyright (c) 2020 Laird Connectivity
# SPDX-License-Identifier: Apache-2.0
menuconfig SI7055
bool "Si7055 Temperature Sensor"
depends on (I2C && HAS_DTS_I2C)
help
Enable I2C-based driver for Si7055 Temperature Sensor.
if SI7055
config SI7055_ENABLE_CHECKSUM
bool "SI7055 Checksum On Measurement"
help
Validates the additional checksum byte for temperature measurements.
endif # SI7055

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@ -0,0 +1,149 @@
/*
* Copyright (c) 2020 Laird Connectivity
* Copyright (c) 2019 Electronut Labs
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT silabs_si7055
#include <drivers/sensor.h>
#include <kernel.h>
#include <device.h>
#include <logging/log.h>
#include <drivers/i2c.h>
#include "si7055.h"
#if CONFIG_SI7055_ENABLE_CHECKSUM
#include <sys/crc.h>
#endif
LOG_MODULE_REGISTER(si7055, CONFIG_SENSOR_LOG_LEVEL);
struct si7055_data {
struct device *i2c_dev;
uint16_t temperature;
};
/**
* @brief function to get temperature
*
* @return int 0 on success
* -EIO for I/O and checksum errors
*/
static int si7055_get_temperature(struct device *i2c_dev,
struct si7055_data *si_data)
{
int retval;
#if CONFIG_SI7055_ENABLE_CHECKSUM
uint8_t temp[SI7055_TEMPERATURE_READ_WITH_CHECKSUM_SIZE];
#else
uint8_t temp[SI7055_TEMPERATURE_READ_NO_CHECKSUM_SIZE];
#endif
retval = i2c_burst_read(i2c_dev, DT_INST_REG_ADDR(0),
SI7055_MEAS_TEMP_MASTER_MODE,
temp, sizeof(temp));
/* Refer to
* https://www.silabs.com/documents/public/data-sheets/Si7050-1-3-4-5-A20.pdf
*/
if (retval == 0) {
#if CONFIG_SI7055_ENABLE_CHECKSUM
if (crc8(temp, SI7055_DATA_SIZE, SI7055_CRC_POLY,
SI7055_CRC_INIT, false) != temp[SI7055_DATA_SIZE]){
LOG_ERR("checksum failed.\n");
return(-EIO);
}
#endif
si_data->temperature = (temp[SI7055_TEMPERATURE_DATA_BYTE_0]
<< 8) |
temp[SI7055_TEMPERATURE_DATA_BYTE_1];
} else {
LOG_ERR("read register err");
}
return retval;
}
/**
* @brief fetch a sample from the sensor
*
* @return 0
*/
static int si7055_sample_fetch(struct device *dev, enum sensor_channel chan)
{
int retval;
struct si7055_data *si_data = dev->driver_data;
retval = si7055_get_temperature(si_data->i2c_dev, si_data);
return retval;
}
/**
* @brief sensor value get
*
* @return -ENOTSUP for unsupported channels
*/
static int si7055_channel_get(struct device *dev, enum sensor_channel chan,
struct sensor_value *val)
{
struct si7055_data *si_data = dev->driver_data;
/* Refer to
* https://www.silabs.com/documents/public/data-sheets/Si7050-1-3-4-5-A20.pdf
*/
if (chan == SENSOR_CHAN_AMBIENT_TEMP) {
int32_t temp_ucelcius = (((SI7055_CONV_FACTOR_1 *
(int32_t)si_data->temperature) /
(__UINT16_MAX__ + 1)) -
SI7055_CONV_FACTOR_2) *
SI7055_MULTIPLIER;
val->val1 = temp_ucelcius / SI7055_DIVIDER;
val->val2 = temp_ucelcius % SI7055_DIVIDER;
LOG_DBG("temperature = val1:%d, val2:%d",
val->val1, val->val2);
return 0;
} else {
return -ENOTSUP;
}
}
static const struct sensor_driver_api si7055_api = {
.sample_fetch = &si7055_sample_fetch,
.channel_get = &si7055_channel_get,
};
/**
* @brief initialize the sensor
*
* @return 0 for success
*/
static int si7055_init(struct device *dev)
{
struct si7055_data *drv_data = dev->driver_data;
drv_data->i2c_dev = device_get_binding(
DT_INST_BUS_LABEL(0));
if (!drv_data->i2c_dev) {
LOG_ERR("i2c master not found.");
return -EINVAL;
}
LOG_DBG("si7055 init ok");
return 0;
}
static struct si7055_data si_data;
DEVICE_AND_API_INIT(si7055, DT_INST_LABEL(0), si7055_init,
&si_data, NULL, POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY, &si7055_api);

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@ -0,0 +1,37 @@
/*
* Copyright (c) 2020 Laird Connectivity
* Copyright (c) 2019 Electronut Labs
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef _SI7055_H
#define _SI7055_H
/* Si7055 register addresses */
#define SI7055_MEAS_TEMP_MASTER_MODE 0xE3
#define SI7055_MEAS_TEMP_NO_MASTER_MODE 0xF3
#define SI7055_RESET 0xFE
#define SI7055_READ_ID_LOW_0 0xFA
#define SI7055_READ_ID_LOW_1 0x0F
#define SI7055_READ_ID_HIGH_0 0xFC
#define SI7055_READ_ID_HIGH_1 0xC9
#define SI7055_FIRMWARE_0 0x84
#define SI7055_FIRMWARE_1 0xB8
/* Si7055 temperature conversion factors and constants */
#define SI7055_CONV_FACTOR_1 17572
#define SI7055_CONV_FACTOR_2 4685
#define SI7055_MULTIPLIER 10000
#define SI7055_DIVIDER 1000000
/* Si7055 buffer sizes and locations */
#define SI7055_TEMPERATURE_READ_NO_CHECKSUM_SIZE 0x02
#define SI7055_TEMPERATURE_READ_WITH_CHECKSUM_SIZE 0x03
#define SI7055_TEMPERATURE_DATA_BYTE_0 0x0
#define SI7055_TEMPERATURE_DATA_BYTE_1 0x1
/* Si7055 Checksum constants */
#define SI7055_CRC_POLY 0x31
#define SI7055_CRC_SIZE sizeof(uint8_t)
#define SI7055_CRC_INIT 0x0
#define SI7055_DATA_SIZE (sizeof(uint8_t) * 2)
#endif /* _SI7055_H */

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@ -267,6 +267,12 @@ test_i2c_si7006: si7006@24 {
reg = <0x24>;
};
test_i2c_si7055: si7055@40 {
compatible = "silabs,si7055";
label = "SI7055";
reg = <0x40>;
};
test_i2c_si7060: si7060@25 {
compatible = "silabs,si7060";
label = "SI7060";

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@ -30,6 +30,7 @@ CONFIG_MS5607=y
CONFIG_OPT3001=y
CONFIG_SHT3XD=y
CONFIG_SI7006=y
CONFIG_SI7055=y
CONFIG_SI7060=y
CONFIG_SX9500=y
CONFIG_TEMP_NRF5=y