zephyr/drivers/sensor/tmp116/tmp116.c

146 lines
3.2 KiB
C

/*
* Copyright (c) 2019 Centaur Analytics, Inc
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <device.h>
#include <drivers/i2c.h>
#include <drivers/sensor.h>
#include <misc/util.h>
#include <misc/byteorder.h>
#include <misc/__assert.h>
#include <logging/log.h>
#include <kernel.h>
#include "tmp116.h"
#define LOG_LEVEL CONFIG_SENSOR_LOG_LEVEL
LOG_MODULE_REGISTER(TMP116);
static int tmp116_reg_read(struct device *dev, u8_t reg, u16_t *val)
{
struct tmp116_data *drv_data = dev->driver_data;
const struct tmp116_dev_config *cfg = dev->config->config_info;
if (i2c_burst_read(drv_data->i2c, cfg->i2c_addr, reg, (u8_t *)val, 2)
< 0) {
return -EIO;
}
*val = sys_be16_to_cpu(*val);
return 0;
}
/**
* @brief Check the Device ID
*
* @param[in] dev Pointer to the device structure
*
* @retval 0 On success
* @retval -EIO Otherwise
*/
static inline int tmp116_device_id_check(struct device *dev)
{
u16_t value;
if (tmp116_reg_read(dev, TMP116_REG_DEVICE_ID, &value) != 0) {
LOG_ERR("%s: Failed to get Device ID register!",
DT_INST_0_TI_TMP116_LABEL);
return -EIO;
}
if (value != TMP116_DEVICE_ID) {
LOG_ERR("%s: Failed to match the device IDs!",
DT_INST_0_TI_TMP116_LABEL);
return -EINVAL;
}
return 0;
}
static int tmp116_sample_fetch(struct device *dev, enum sensor_channel chan)
{
struct tmp116_data *drv_data = dev->driver_data;
u16_t value;
int rc;
__ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL ||
chan == SENSOR_CHAN_AMBIENT_TEMP);
/* clear sensor values */
drv_data->sample = 0U;
/* Get the most recent temperature measurement */
rc = tmp116_reg_read(dev, TMP116_REG_TEMP, &value);
if (rc < 0) {
LOG_ERR("%s: Failed to read from TEMP register!",
DT_INST_0_TI_TMP116_LABEL);
return rc;
}
/* store measurements to the driver */
drv_data->sample = (s16_t)value;
return 0;
}
static int tmp116_channel_get(struct device *dev, enum sensor_channel chan,
struct sensor_value *val)
{
struct tmp116_data *drv_data = dev->driver_data;
s32_t tmp;
if (chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
/*
* See datasheet "Temperature Results and Limits" section for more
* details on processing sample data.
*/
tmp = (s32_t)drv_data->sample * TMP116_RESOLUTION;
val->val1 = tmp / 10000000; /* Tens of uCelsius */
val->val2 = tmp % 10000000;
return 0;
}
static const struct sensor_driver_api tmp116_driver_api = {
.sample_fetch = tmp116_sample_fetch,
.channel_get = tmp116_channel_get
};
static int tmp116_init(struct device *dev)
{
struct tmp116_data *drv_data = dev->driver_data;
int rc;
/* Bind to the I2C bus that the sensor is connected */
drv_data->i2c = device_get_binding(DT_INST_0_TI_TMP116_BUS_NAME);
if (!drv_data->i2c) {
LOG_ERR("Cannot bind to %s device!",
DT_INST_0_TI_TMP116_BUS_NAME);
return -EINVAL;
}
/* Check the Device ID */
rc = tmp116_device_id_check(dev);
if (rc < 0) {
return rc;
}
return 0;
}
static struct tmp116_data tmp116_data;
static const struct tmp116_dev_config tmp116_config = {
.i2c_addr = DT_INST_0_TI_TMP116_BASE_ADDRESS,
};
DEVICE_AND_API_INIT(hdc1080, DT_INST_0_TI_TMP116_LABEL, tmp116_init,
&tmp116_data, &tmp116_config, POST_KERNEL,
CONFIG_SENSOR_INIT_PRIORITY, &tmp116_driver_api);