// SPDX-License-Identifier: GPL-2.0+ /* * Copyright (c) Vaisala Oyj. All rights reserved. */ #include <linux/init.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/of.h> #include <linux/nvmem-consumer.h> #include <linux/platform_device.h> #include <linux/reboot-mode.h> struct nvmem_reboot_mode { struct reboot_mode_driver reboot; struct nvmem_cell *cell; }; static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, unsigned int magic) { int ret; struct nvmem_reboot_mode *nvmem_rbm; nvmem_rbm = container_of(reboot, struct nvmem_reboot_mode, reboot); ret = nvmem_cell_write(nvmem_rbm->cell, &magic, sizeof(magic)); if (ret < 0) dev_err(reboot->dev, "update reboot mode bits failed\n"); return ret; } static int nvmem_reboot_mode_probe(struct platform_device *pdev) { int ret; struct nvmem_reboot_mode *nvmem_rbm; nvmem_rbm = devm_kzalloc(&pdev->dev, sizeof(*nvmem_rbm), GFP_KERNEL); if (!nvmem_rbm) return -ENOMEM; nvmem_rbm->reboot.dev = &pdev->dev; nvmem_rbm->reboot.write = nvmem_reboot_mode_write; nvmem_rbm->cell = devm_nvmem_cell_get(&pdev->dev, "reboot-mode"); if (IS_ERR(nvmem_rbm->cell)) { return dev_err_probe(&pdev->dev, PTR_ERR(nvmem_rbm->cell), "failed to get the nvmem cell reboot-mode\n"); } ret = devm_reboot_mode_register(&pdev->dev, &nvmem_rbm->reboot); if (ret) dev_err(&pdev->dev, "can't register reboot mode\n"); return ret; } static const struct of_device_id nvmem_reboot_mode_of_match[] = { { .compatible = "nvmem-reboot-mode" }, {} }; MODULE_DEVICE_TABLE(of, nvmem_reboot_mode_of_match); static struct platform_driver nvmem_reboot_mode_driver = { .probe = nvmem_reboot_mode_probe, .driver = { .name = "nvmem-reboot-mode", .of_match_table = nvmem_reboot_mode_of_match, }, }; module_platform_driver(nvmem_reboot_mode_driver); MODULE_AUTHOR("Nandor Han <nandor.han@vaisala.com>"); MODULE_DESCRIPTION("NVMEM reboot mode driver"); MODULE_LICENSE("GPL");