blob: 95e22d6aba94ca7c45ddd51b3a67b2253811887a [file] [log] [blame]
/*
* Copyright (c) 2016 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT maxim_max44009
#include <zephyr/device.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/sensor.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/logging/log.h>
#include "max44009.h"
LOG_MODULE_REGISTER(MAX44009, CONFIG_SENSOR_LOG_LEVEL);
static int max44009_reg_read(const struct device *dev, uint8_t reg,
uint8_t *val, bool send_stop)
{
const struct max44009_config *config = dev->config;
struct i2c_msg msgs[2] = {
{
.buf = &reg,
.len = 1,
.flags = I2C_MSG_WRITE,
},
{
.buf = val,
.len = 1,
.flags = I2C_MSG_READ,
},
};
if (send_stop) {
msgs[1].flags |= I2C_MSG_STOP;
}
if (i2c_transfer_dt(&config->i2c, msgs, 2) != 0) {
return -EIO;
}
return 0;
}
static int max44009_reg_write(const struct device *dev, uint8_t reg,
uint8_t val)
{
const struct max44009_config *config = dev->config;
uint8_t tx_buf[2] = {reg, val};
return i2c_write_dt(&config->i2c, tx_buf, sizeof(tx_buf));
}
static int max44009_reg_update(const struct device *dev, uint8_t reg,
uint8_t mask, uint8_t val)
{
uint8_t old_val = 0U;
uint8_t new_val = 0U;
if (max44009_reg_read(dev, reg, &old_val, true) != 0) {
return -EIO;
}
new_val = old_val & ~mask;
new_val |= val & mask;
return max44009_reg_write(dev, reg, new_val);
}
static int max44009_attr_set(const struct device *dev,
enum sensor_channel chan,
enum sensor_attribute attr,
const struct sensor_value *val)
{
uint8_t value;
uint32_t cr;
if (chan != SENSOR_CHAN_LIGHT) {
return -ENOTSUP;
}
switch (attr) {
case SENSOR_ATTR_SAMPLING_FREQUENCY:
/* convert rate to mHz */
cr = val->val1 * 1000 + val->val2 / 1000;
/* the sensor supports 1.25Hz or continuous conversion */
switch (cr) {
case 1250:
value = 0U;
break;
default:
value = MAX44009_CONTINUOUS_SAMPLING;
}
if (max44009_reg_update(dev, MAX44009_REG_CONFIG,
MAX44009_SAMPLING_CONTROL_BIT,
value) != 0) {
LOG_DBG("Failed to set attribute!");
return -EIO;
}
return 0;
default:
return -ENOTSUP;
}
return 0;
}
static int max44009_sample_fetch(const struct device *dev,
enum sensor_channel chan)
{
struct max44009_data *drv_data = dev->data;
uint8_t val_h, val_l;
__ASSERT_NO_MSG(chan == SENSOR_CHAN_ALL || chan == SENSOR_CHAN_LIGHT);
drv_data->sample = 0U;
if (max44009_reg_read(dev, MAX44009_REG_LUX_HIGH_BYTE, &val_h,
false) != 0) {
return -EIO;
}
if (max44009_reg_read(dev, MAX44009_REG_LUX_LOW_BYTE, &val_l,
true) != 0) {
return -EIO;
}
drv_data->sample = ((uint16_t)val_h) << 8;
drv_data->sample += val_l;
return 0;
}
static int max44009_channel_get(const struct device *dev,
enum sensor_channel chan,
struct sensor_value *val)
{
struct max44009_data *drv_data = dev->data;
uint32_t uval;
if (chan != SENSOR_CHAN_LIGHT) {
return -ENOTSUP;
}
/**
* sample consists of 4 bits of exponent and 8 bits of mantissa
* bits 15 to 12 are exponent bits
* bits 11 to 8 and 3 to 0 are the mantissa bits
*/
uval = drv_data->sample;
uval = (uval & MAX44009_MANTISSA_LOW_NIBBLE_MASK) +
((uval & MAX44009_MANTISSA_HIGH_NIBBLE_MASK) >> 4);
uval = uval << (drv_data->sample >> MAX44009_SAMPLE_EXPONENT_SHIFT);
/* lux is the integer of sample output multiplied by 0.045. */
val->val1 = (uval * 45U) / 1000;
val->val2 = ((uval * 45U) % 1000) * 1000U;
return 0;
}
static const struct sensor_driver_api max44009_driver_api = {
.attr_set = max44009_attr_set,
.sample_fetch = max44009_sample_fetch,
.channel_get = max44009_channel_get,
};
int max44009_init(const struct device *dev)
{
const struct max44009_config *config = dev->config;
if (!device_is_ready(config->i2c.bus)) {
LOG_ERR("Bus device is not ready");
return -ENODEV;
}
return 0;
}
#define MAX44009_DEFINE(inst) \
static struct max44009_data max44009_data_##inst; \
\
static const struct max44009_config max44009_config_##inst = { \
.i2c = I2C_DT_SPEC_INST_GET(inst), \
}; \
\
DEVICE_DT_INST_DEFINE(inst, max44009_init, NULL, \
&max44009_data_##inst, &max44009_config_##inst, POST_KERNEL, \
CONFIG_SENSOR_INIT_PRIORITY, &max44009_driver_api); \
DT_INST_FOREACH_STATUS_OKAY(MAX44009_DEFINE)