blob: 759c00c91f484668519f7e9f69055ca7fc2e6f32 [file] [log] [blame]
/*
* Copyright (c) 2023 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT asahi_kasei_akm09918c
#include <zephyr/device.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/kernel.h>
#include <zephyr/drivers/sensor.h>
#include <zephyr/sys/__assert.h>
#include <zephyr/sys/byteorder.h>
#include <zephyr/sys/util.h>
#include <zephyr/logging/log.h>
#include "akm09918c.h"
#include "akm09918c_reg.h"
LOG_MODULE_REGISTER(AKM09918C, CONFIG_SENSOR_LOG_LEVEL);
static int akm09918c_sample_fetch(const struct device *dev, enum sensor_channel chan)
{
struct akm09918c_data *data = dev->data;
const struct akm09918c_config *cfg = dev->config;
uint8_t buf[9] = {0};
if (chan != SENSOR_CHAN_ALL && chan != SENSOR_CHAN_MAGN_X && chan != SENSOR_CHAN_MAGN_Y &&
chan != SENSOR_CHAN_MAGN_Z && chan != SENSOR_CHAN_MAGN_XYZ) {
LOG_WRN("Invalid channel %d", chan);
return -EINVAL;
}
if (data->mode == AKM09918C_CNTL2_PWR_DOWN) {
if (i2c_reg_write_byte_dt(&cfg->i2c, AKM09918C_REG_CNTL2,
AKM09918C_CNTL2_SINGLE_MEASURE) != 0) {
LOG_ERR("Failed to start measurement.");
return -EIO;
}
/* Wait for sample */
LOG_DBG("Waiting for sample...");
k_usleep(AKM09918C_MEASURE_TIME_US);
}
/* We have to read through the TMPS register or the data_ready bit won't clear */
if (i2c_burst_read_dt(&cfg->i2c, AKM09918C_REG_ST1, buf, ARRAY_SIZE(buf)) != 0) {
LOG_ERR("Failed to read sample data.");
return -EIO;
}
if (FIELD_GET(AKM09918C_ST1_DRDY, buf[0]) == 0) {
LOG_ERR("Data not ready, st1=0x%02x", buf[0]);
return -EBUSY;
}
data->x_sample = sys_le16_to_cpu(buf[1] | (buf[2] << 8));
data->y_sample = sys_le16_to_cpu(buf[3] | (buf[4] << 8));
data->z_sample = sys_le16_to_cpu(buf[5] | (buf[6] << 8));
return 0;
}
static void akm09918c_convert(struct sensor_value *val, int16_t sample)
{
int64_t conv_val = sample * AKM09918C_MICRO_GAUSS_PER_BIT;
val->val1 = conv_val / 1000000;
val->val2 = conv_val - (val->val1 * 1000000);
}
static int akm09918c_channel_get(const struct device *dev, enum sensor_channel chan,
struct sensor_value *val)
{
struct akm09918c_data *data = dev->data;
if (chan == SENSOR_CHAN_MAGN_XYZ) {
akm09918c_convert(val, data->x_sample);
akm09918c_convert(val + 1, data->y_sample);
akm09918c_convert(val + 2, data->z_sample);
} else if (chan == SENSOR_CHAN_MAGN_X) {
akm09918c_convert(val, data->x_sample);
} else if (chan == SENSOR_CHAN_MAGN_Y) {
akm09918c_convert(val, data->y_sample);
} else if (chan == SENSOR_CHAN_MAGN_Z) {
akm09918c_convert(val, data->z_sample);
} else {
LOG_WRN("Invalid channel %d", chan);
return -EINVAL;
}
return 0;
}
static int akm09918c_attr_get(const struct device *dev, enum sensor_channel chan,
enum sensor_attribute attr, struct sensor_value *val)
{
struct akm09918c_data *data = dev->data;
switch (chan) {
case SENSOR_CHAN_MAGN_X:
case SENSOR_CHAN_MAGN_Y:
case SENSOR_CHAN_MAGN_Z:
case SENSOR_CHAN_MAGN_XYZ:
if (attr != SENSOR_ATTR_SAMPLING_FREQUENCY) {
LOG_WRN("Invalid attribute %d", attr);
return -EINVAL;
}
akm09918c_reg_to_hz(data->mode, val);
break;
default:
LOG_WRN("Invalid channel %d", chan);
return -EINVAL;
}
return 0;
}
static int akm09918c_attr_set(const struct device *dev, enum sensor_channel chan,
enum sensor_attribute attr, const struct sensor_value *val)
{
const struct akm09918c_config *cfg = dev->config;
struct akm09918c_data *data = dev->data;
int res;
switch (chan) {
case SENSOR_CHAN_MAGN_X:
case SENSOR_CHAN_MAGN_Y:
case SENSOR_CHAN_MAGN_Z:
case SENSOR_CHAN_MAGN_XYZ:
if (attr != SENSOR_ATTR_SAMPLING_FREQUENCY) {
LOG_WRN("Invalid attribute %d", attr);
return -EINVAL;
}
uint8_t mode = akm09918c_hz_to_reg(val);
res = i2c_reg_write_byte_dt(&cfg->i2c, AKM09918C_REG_CNTL2, mode);
if (res != 0) {
LOG_ERR("Failed to set sample frequency");
return -EIO;
}
data->mode = mode;
break;
default:
LOG_WRN("Invalid channel %d", chan);
return -EINVAL;
}
return 0;
}
static const struct sensor_driver_api akm09918c_driver_api = {
.sample_fetch = akm09918c_sample_fetch,
.channel_get = akm09918c_channel_get,
.attr_get = akm09918c_attr_get,
.attr_set = akm09918c_attr_set,
};
static inline int akm09918c_check_who_am_i(const struct i2c_dt_spec *i2c)
{
uint8_t buffer[2];
int rc;
rc = i2c_burst_read_dt(i2c, AKM09918C_REG_WIA1, buffer, ARRAY_SIZE(buffer));
if (rc != 0) {
LOG_ERR("Failed to read who-am-i register (rc=%d)", rc);
return -EIO;
}
if (buffer[0] != AKM09918C_WIA1 || buffer[1] != AKM09918C_WIA2) {
LOG_ERR("Wrong who-am-i value");
return -EINVAL;
}
return 0;
}
static int akm09918c_init(const struct device *dev)
{
const struct akm09918c_config *cfg = dev->config;
struct akm09918c_data *data = dev->data;
int rc;
if (!i2c_is_ready_dt(&cfg->i2c)) {
LOG_ERR("I2C bus device not ready");
return -ENODEV;
}
/* Soft reset the chip */
rc = i2c_reg_write_byte_dt(&cfg->i2c, AKM09918C_REG_CNTL3,
FIELD_PREP(AKM09918C_CNTL3_SRST, 1));
if (rc != 0) {
LOG_ERR("Failed to soft reset");
return -EIO;
}
/* check chip ID */
rc = akm09918c_check_who_am_i(&cfg->i2c);
if (rc != 0) {
return rc;
}
data->mode = AKM09918C_CNTL2_PWR_DOWN;
return 0;
}
#define AKM09918C_DEFINE(inst) \
static struct akm09918c_data akm09918c_data_##inst; \
\
static const struct akm09918c_config akm09918c_config_##inst = { \
.i2c = I2C_DT_SPEC_INST_GET(inst), \
}; \
\
SENSOR_DEVICE_DT_INST_DEFINE(inst, akm09918c_init, NULL, &akm09918c_data_##inst, \
&akm09918c_config_##inst, POST_KERNEL, \
CONFIG_SENSOR_INIT_PRIORITY, &akm09918c_driver_api);
DT_INST_FOREACH_STATUS_OKAY(AKM09918C_DEFINE)