/*
* Copyright (c) 2016 Firmwave
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <device.h>
#include <i2c.h>
#include <misc/byteorder.h>
#include <misc/util.h>
#include <kernel.h>
#include <sensor.h>
#include <misc/__assert.h>
#define SYS_LOG_DOMAIN "TMP112"
#define SYS_LOG_LEVEL CONFIG_SYS_LOG_SENSOR_LEVEL
#include <logging/sys_log.h>
#define TMP112_I2C_ADDRESS CONFIG_TMP112_I2C_ADDR
#define TMP112_REG_TEMPERATURE 0x00
#define TMP112_D0_BIT BIT(0)
#define TMP112_REG_CONFIG 0x01
#define TMP112_EM_BIT BIT(4)
#define TMP112_CR0_BIT BIT(6)
#define TMP112_CR1_BIT BIT(7)
/* scale in micro degrees Celsius */
#define TMP112_TEMP_SCALE 62500
struct tmp112_data {
struct device *i2c;
int16_t sample;
};
static int tmp112_reg_read(struct tmp112_data *drv_data,
uint8_t reg, uint16_t *val)
{
struct i2c_msg msgs[2] = {
{
.buf = ®,
.len = 1,
.flags = I2C_MSG_WRITE | I2C_MSG_RESTART,
},
{
.buf = (uint8_t *)val,
.len = 2,
.flags = I2C_MSG_READ | I2C_MSG_STOP,
},
};
if (i2c_transfer(drv_data->i2c, msgs, 2, TMP112_I2C_ADDRESS) < 0) {
return -EIO;
}
*val = sys_be16_to_cpu(*val);
return 0;
}
static int tmp112_reg_write(struct tmp112_data *drv_data,
uint8_t reg, uint16_t val)
{
uint8_t tx_buf[3] = {reg, val >> 8, val & 0xFF};
return i2c_write(drv_data->i2c, tx_buf, sizeof(tx_buf),
TMP112_I2C_ADDRESS);
}
static int tmp112_reg_update(struct tmp112_data *drv_data, uint8_t reg,
uint16_t mask, uint16_t val)
{
uint16_t old_val = 0;
uint16_t new_val;
if (tmp112_reg_read(drv_data, reg, &old_val) < 0) {
return -EIO;
}
new_val = old_val & ~mask;
new_val |= val & mask;
return tmp112_reg_write(drv_data, reg, new_val);
}
static int tmp112_attr_set(struct device *dev,
enum sensor_channel chan,
enum sensor_attribute attr,
const struct sensor_value *val)
{
struct tmp112_data *drv_data = dev->driver_data;
int64_t value;
uint16_t cr;
if (chan != SENSOR_CHAN_TEMP) {
return -ENOTSUP;
}
switch (attr) {
case SENSOR_ATTR_FULL_SCALE:
/* the sensor supports two ranges -55 to 128 and -55 to 150 */
/* the value contains the upper limit */
if (val->val1 == 128) {
value = 0x0000;
} else if (val->val1 == 150) {
value = TMP112_EM_BIT;
} else {
return -ENOTSUP;
}
if (tmp112_reg_update(drv_data, TMP112_REG_CONFIG,
TMP112_EM_BIT, value) < 0) {
SYS_LOG_DBG("Failed to set attribute!");
return -EIO;
}
return 0;
case SENSOR_ATTR_SAMPLING_FREQUENCY:
/* conversion rate in mHz */
cr = val->val1 * 1000 + val->val2 / 1000;
/* the sensor supports 0.25Hz, 1Hz, 4Hz and 8Hz */
/* conversion rate */
switch (cr) {
case 250:
value = 0x0000;
break;
case 1000:
value = TMP112_CR0_BIT;
break;
case 4000:
value = TMP112_CR1_BIT;
break;
case 8000:
value = TMP112_CR0_BIT | TMP112_CR1_BIT;
break;
default:
return -ENOTSUP;
}
if (tmp112_reg_update(drv_data, TMP112_REG_CONFIG,
TMP112_CR0_BIT | TMP112_CR1_BIT,
value) < 0) {
SYS_LOG_DBG("Failed to set attribute!");
return -EIO;
}
return 0;
default:
return -ENOTSUP;
}
return 0;
}
static int tmp112_sample_fetch(struct device *dev, enum sensor_channel chan)
{
struct tmp112_data *drv_data = dev->driver_data;
uint16_t val;
__ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL || chan == SENSOR_CHAN_TEMP);
if (tmp112_reg_read(drv_data, TMP112_REG_TEMPERATURE, &val) < 0) {
return -EIO;
}
if (val & TMP112_D0_BIT) {
drv_data->sample = arithmetic_shift_right((int16_t)val, 3);
} else {
drv_data->sample = arithmetic_shift_right((int16_t)val, 4);
}
return 0;
}
static int tmp112_channel_get(struct device *dev,
enum sensor_channel chan,
struct sensor_value *val)
{
struct tmp112_data *drv_data = dev->driver_data;
int32_t uval;
if (chan != SENSOR_CHAN_TEMP) {
return -ENOTSUP;
}
uval = (int32_t)drv_data->sample * TMP112_TEMP_SCALE;
val->val1 = uval / 1000000;
val->val2 = uval % 1000000;
return 0;
}
static const struct sensor_driver_api tmp112_driver_api = {
.attr_set = tmp112_attr_set,
.sample_fetch = tmp112_sample_fetch,
.channel_get = tmp112_channel_get,
};
int tmp112_init(struct device *dev)
{
struct tmp112_data *drv_data = dev->driver_data;
drv_data->i2c = device_get_binding(CONFIG_TMP112_I2C_MASTER_DEV_NAME);
if (drv_data->i2c == NULL) {
SYS_LOG_DBG("Failed to get pointer to %s device!",
CONFIG_TMP112_I2C_MASTER_DEV_NAME);
return -EINVAL;
}
dev->driver_api = &tmp112_driver_api;
return 0;
}
static struct tmp112_data tmp112_driver;
DEVICE_INIT(tmp112, CONFIG_TMP112_NAME, tmp112_init, &tmp112_driver,
NULL, POST_KERNEL, CONFIG_SENSOR_INIT_PRIORITY);