drivers/dac/dac_ad5592.c

/*
 * Copyright (c) 2023 Grinn
 * SPDX-License-Identifier: Apache-2.0
 */

#define DT_DRV_COMPAT adi_ad5592_dac

#include <zephyr/drivers/dac.h>
#include <zephyr/kernel.h>
#include <zephyr/sys/byteorder.h>

#include <zephyr/drivers/mfd/ad5592.h>

#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(dac_ad5592, CONFIG_DAC_LOG_LEVEL);

#define AD5592_DAC_RESOLUTION 12
#define AD5592_DAC_WR_MSB_BIT BIT(15)
#define AD5592_DAC_CHANNEL_SHIFT_VAL 12

struct dac_ad5592_config {
	const struct device *mfd_dev;
};

struct dac_ad5592_data {
	uint8_t dac_conf;
};

static int dac_ad5592_channel_setup(const struct device *dev,
				    const struct dac_channel_cfg *channel_cfg)
{
	const struct dac_ad5592_config *config = dev->config;
	struct dac_ad5592_data *data = dev->data;

	if (channel_cfg->channel_id >= AD5592_PIN_MAX) {
		LOG_ERR("Invalid channel number %d", channel_cfg->channel_id);
		return -EINVAL;
	}

	if (channel_cfg->resolution != AD5592_DAC_RESOLUTION) {
		LOG_ERR("Invalid resolution %d", channel_cfg->resolution);
		return -EINVAL;
	}

	data->dac_conf |= BIT(channel_cfg->channel_id);

	return mfd_ad5592_write_reg(config->mfd_dev, AD5592_REG_LDAC_EN, data->dac_conf);
}

static int dac_ad5592_write_value(const struct device *dev, uint8_t channel,
				  uint32_t value)
{
	const struct dac_ad5592_config *config = dev->config;
	uint16_t msg;

	if (channel >= AD5592_PIN_MAX) {
		LOG_ERR("Invalid channel number %d", channel);
		return -EINVAL;
	}

	if (value >= (1 << AD5592_DAC_RESOLUTION)) {
		LOG_ERR("Value %d out of range", value);
		return -EINVAL;
	}

	msg = sys_cpu_to_be16(AD5592_DAC_WR_MSB_BIT |
			      channel << AD5592_DAC_CHANNEL_SHIFT_VAL |
			      value);

	return mfd_ad5592_write_raw(config->mfd_dev, msg);
}

static const struct dac_driver_api dac_ad5592_api = {
	.channel_setup = dac_ad5592_channel_setup,
	.write_value = dac_ad5592_write_value,
};

static int dac_ad5592_init(const struct device *dev)
{
	const struct dac_ad5592_config *config = dev->config;
	int ret;

	if (!device_is_ready(config->mfd_dev)) {
		return -ENODEV;
	}

	ret = mfd_ad5592_write_reg(config->mfd_dev, AD5592_REG_PD_REF_CTRL, AD5592_EN_REF);
	if (ret < 0) {
		return ret;
	}

	return 0;
}

#define DAC_AD5592_DEFINE(inst)							\
	static const struct dac_ad5592_config dac_ad5592_config##inst = {	\
		.mfd_dev = DEVICE_DT_GET(DT_INST_PARENT(inst)),			\
	};									\
										\
	struct dac_ad5592_data dac_ad5592_data##inst;				\
										\
	DEVICE_DT_INST_DEFINE(inst, dac_ad5592_init, NULL,			\
			      &dac_ad5592_data##inst, &dac_ad5592_config##inst, \
			      POST_KERNEL, CONFIG_MFD_INIT_PRIORITY,		\
			      &dac_ad5592_api);

DT_INST_FOREACH_STATUS_OKAY(DAC_AD5592_DEFINE)