zephyr/drivers/mfd/mfd_max31790.c

82 lines
2.5 KiB
C

/*
* Copyright (c) 2024 SILA Embedded Solutions GmbH
*
* SPDX-License-Identifier: Apache-2.0
*/
#define DT_DRV_COMPAT maxim_max31790
#include <zephyr/device.h>
#include <zephyr/drivers/i2c.h>
#include <zephyr/drivers/mfd/max31790.h>
#include <zephyr/sys/util.h>
#include <zephyr/kernel.h>
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(max_max31790, CONFIG_MFD_LOG_LEVEL);
struct max31790_config {
struct i2c_dt_spec i2c;
};
static void max31790_set_globalconfiguration_i2cwatchdog(uint8_t *destination, uint8_t value)
{
uint8_t length = MAX37190_GLOBALCONFIGURATION_I2CWATCHDOG_LENGTH;
uint8_t pos = MAX37190_GLOBALCONFIGURATION_I2CWATCHDOG_POS;
*destination &= ~GENMASK(pos + length - 1, pos);
*destination |= FIELD_PREP(GENMASK(pos + length - 1, pos), value);
}
static int max31790_init(const struct device *dev)
{
const struct max31790_config *config = dev->config;
int result;
uint8_t reg_value;
if (!i2c_is_ready_dt(&config->i2c)) {
LOG_ERR("I2C device not ready");
return -ENODEV;
}
reg_value = 0;
reg_value &= ~MAX37190_GLOBALCONFIGURATION_STANDBY_BIT;
reg_value |= MAX37190_GLOBALCONFIGURATION_RESET_BIT;
reg_value |= MAX37190_GLOBALCONFIGURATION_BUSTIMEOUT_BIT;
reg_value &= ~MAX37190_GLOBALCONFIGURATION_OSCILLATORSELECTION_BIT;
max31790_set_globalconfiguration_i2cwatchdog(&reg_value, 0);
reg_value &= ~MAX37190_GLOBALCONFIGURATION_I2CWATCHDOGSTATUS_BIT;
result = i2c_reg_write_byte_dt(&config->i2c, MAX37190_REGISTER_GLOBALCONFIGURATION,
reg_value);
if (result != 0) {
return result;
}
k_sleep(K_USEC(MAX31790_RESET_TIMEOUT_IN_US));
result = i2c_reg_read_byte_dt(&config->i2c, MAX37190_REGISTER_GLOBALCONFIGURATION,
&reg_value);
if (result != 0) {
return result;
}
if ((reg_value & MAX37190_GLOBALCONFIGURATION_STANDBY_BIT) != 0) {
LOG_ERR("PWM controller is still in standby");
return -ENODEV;
}
return 0;
}
#define MAX31790_INIT(inst) \
static const struct max31790_config max31790_##inst##_config = { \
.i2c = I2C_DT_SPEC_INST_GET(inst), \
}; \
\
DEVICE_DT_INST_DEFINE(inst, max31790_init, NULL, NULL, &max31790_##inst##_config, \
POST_KERNEL, CONFIG_MFD_INIT_PRIORITY, NULL);
DT_INST_FOREACH_STATUS_OKAY(MAX31790_INIT);