subsys/nvmem/nvmem.c

/*
 * Copyright (c) 2025 Basalte bv
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <errno.h>
#include <zephyr/drivers/bbram.h>
#include <zephyr/drivers/eeprom.h>
#include <zephyr/drivers/flash.h>
#include <zephyr/drivers/otp.h>
#include <zephyr/nvmem.h>
#include <zephyr/sys/__assert.h>

int nvmem_cell_read(const struct nvmem_cell *cell, void *buf, off_t off, size_t len)
{
	__ASSERT_NO_MSG(cell != NULL);

	if (off < 0 || cell->size < off + len) {
		return -EINVAL;
	}

	if (!device_is_ready(cell->dev)) {
		return -ENODEV;
	}

	if (IS_ENABLED(CONFIG_NVMEM_BBRAM) && DEVICE_API_IS(bbram, cell->dev)) {
		return bbram_read(cell->dev, cell->offset + off, len, buf);
	}

	if (IS_ENABLED(CONFIG_NVMEM_EEPROM) && DEVICE_API_IS(eeprom, cell->dev)) {
		return eeprom_read(cell->dev, cell->offset + off, buf, len);
	}

	if (IS_ENABLED(CONFIG_NVMEM_FLASH) && DEVICE_API_IS(flash, cell->dev)) {
		return flash_read(cell->dev, cell->offset + off, buf, len);
	}

	if (IS_ENABLED(CONFIG_NVMEM_OTP) && DEVICE_API_IS(otp, cell->dev)) {
		return otp_read(cell->dev, cell->offset + off, buf, len);
	}

	return -ENXIO;
}

int nvmem_cell_write(const struct nvmem_cell *cell, const void *buf, off_t off, size_t len)
{
	__ASSERT_NO_MSG(cell != NULL);

	if (off < 0 || cell->size < off + len) {
		return -EINVAL;
	}

	if (cell->read_only) {
		return -EROFS;
	}

	if (!device_is_ready(cell->dev)) {
		return -ENODEV;
	}

	if (IS_ENABLED(CONFIG_NVMEM_BBRAM) && DEVICE_API_IS(bbram, cell->dev)) {
		return bbram_write(cell->dev, cell->offset + off, len, buf);
	}

	if (IS_ENABLED(CONFIG_NVMEM_EEPROM) && DEVICE_API_IS(eeprom, cell->dev)) {
		return eeprom_write(cell->dev, cell->offset + off, buf, len);
	}

	if (IS_ENABLED(CONFIG_NVMEM_FLASH_WRITE) && DEVICE_API_IS(flash, cell->dev)) {
		return flash_write(cell->dev, cell->offset + off, buf, len);
	}

	if (IS_ENABLED(CONFIG_NVMEM_OTP_WRITE) && DEVICE_API_IS(otp, cell->dev)) {
		return otp_program(cell->dev, cell->offset + off, buf, len);
	}

	return -ENXIO;
}