zephyr/drivers/sensor/amd_sb_tsi/sb_tsi.c

132 lines
3.0 KiB
C

/*
* Copyright (c) 2023 Google LLC
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT amd_sb_tsi
#include <zephyr/device.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/sensor.h>
#include <zephyr/pm/device.h>
#include <zephyr/pm/device_runtime.h>
#include <zephyr/logging/log.h>
#include "sb_tsi.h"
LOG_MODULE_REGISTER(AMD_SB_TSI, CONFIG_SENSOR_LOG_LEVEL);
struct sb_tsi_data {
uint8_t sample_int;
uint8_t sample_dec;
};
struct sb_tsi_config {
struct i2c_dt_spec i2c;
};
static int sb_tsi_sample_fetch(const struct device *dev,
enum sensor_channel chan)
{
struct sb_tsi_data *data = dev->data;
const struct sb_tsi_config *config = dev->config;
enum pm_device_state pm_state;
int res;
(void)pm_device_state_get(dev, &pm_state);
if (pm_state != PM_DEVICE_STATE_ACTIVE) {
return -EIO;
}
if (chan != SENSOR_CHAN_ALL && chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
/*
* ReadOrder specifies the order for atomically reading the temp.
* The reset value is 0, which means reading Int latches Dec.
*/
res = i2c_reg_read_byte_dt(&config->i2c, SB_TSI_TEMP_INT, &data->sample_int);
if (res) {
return res;
}
res = i2c_reg_read_byte_dt(&config->i2c, SB_TSI_TEMP_DEC, &data->sample_dec);
if (res) {
return res;
}
return 0;
}
static int sb_tsi_channel_get(const struct device *dev,
enum sensor_channel chan,
struct sensor_value *val)
{
struct sb_tsi_data *data = dev->data;
if (chan != SENSOR_CHAN_AMBIENT_TEMP) {
return -ENOTSUP;
}
val->val1 = data->sample_int;
val->val2 = (data->sample_dec >> SB_TSI_TEMP_DEC_SHIFT) *
(1000000 / SB_TSI_TEMP_DEC_SCALE);
return 0;
}
static const struct sensor_driver_api sb_tsi_driver_api = {
.sample_fetch = sb_tsi_sample_fetch,
.channel_get = sb_tsi_channel_get,
};
static int sb_tsi_init(const struct device *dev)
{
const struct sb_tsi_config *config = dev->config;
int res = 0;
if (!i2c_is_ready_dt(&config->i2c)) {
LOG_ERR("I2C device not ready");
return -ENODEV;
}
#ifdef CONFIG_PM_DEVICE_RUNTIME
pm_device_init_suspended(dev);
res = pm_device_runtime_enable(dev);
if (res) {
LOG_ERR("Failed to enable runtime power management");
}
#endif
return res;
}
#ifdef CONFIG_PM_DEVICE
static int sb_tsi_pm_action(const struct device *dev, enum pm_device_action action)
{
switch (action) {
case PM_DEVICE_ACTION_TURN_ON:
case PM_DEVICE_ACTION_RESUME:
case PM_DEVICE_ACTION_TURN_OFF:
case PM_DEVICE_ACTION_SUSPEND:
return 0;
default:
return -ENOTSUP;
}
}
#endif
#define SB_TSI_INST(inst) \
static struct sb_tsi_data sb_tsi_data_##inst; \
static const struct sb_tsi_config sb_tsi_config_##inst = { \
.i2c = I2C_DT_SPEC_INST_GET(inst), \
}; \
PM_DEVICE_DT_INST_DEFINE(inst, sb_tsi_pm_action); \
SENSOR_DEVICE_DT_INST_DEFINE(inst, sb_tsi_init, PM_DEVICE_DT_INST_GET(inst), \
&sb_tsi_data_##inst, &sb_tsi_config_##inst, POST_KERNEL, \
CONFIG_SENSOR_INIT_PRIORITY, &sb_tsi_driver_api);
DT_INST_FOREACH_STATUS_OKAY(SB_TSI_INST)