| 1 | // SPDX-License-Identifier: GPL-2.0+ |
|---|
| 2 | /* |
|---|
| 3 | * Copyright (c) Vaisala Oyj. All rights reserved. |
|---|
| 4 | */ |
|---|
| 5 | |
|---|
| 6 | #include <linux/init.h> |
|---|
| 7 | #include <linux/module.h> |
|---|
| 8 | #include <linux/kernel.h> |
|---|
| 9 | #include <linux/of.h> |
|---|
| 10 | #include <linux/nvmem-consumer.h> |
|---|
| 11 | #include <linux/platform_device.h> |
|---|
| 12 | #include <linux/reboot-mode.h> |
|---|
| 13 | |
|---|
| 14 | struct nvmem_reboot_mode { |
|---|
| 15 | struct reboot_mode_driver reboot; |
|---|
| 16 | struct nvmem_cell *cell; |
|---|
| 17 | }; |
|---|
| 18 | |
|---|
| 19 | static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, |
|---|
| 20 | unsigned int magic) |
|---|
| 21 | { |
|---|
| 22 | int ret; |
|---|
| 23 | struct nvmem_reboot_mode *nvmem_rbm; |
|---|
| 24 | |
|---|
| 25 | nvmem_rbm = container_of(reboot, struct nvmem_reboot_mode, reboot); |
|---|
| 26 | |
|---|
| 27 | ret = nvmem_cell_write(cell: nvmem_rbm->cell, buf: &magic, len: sizeof(magic)); |
|---|
| 28 | if (ret < 0) |
|---|
| 29 | dev_err(reboot->dev, "update reboot mode bits failed\n" ); |
|---|
| 30 | |
|---|
| 31 | return ret; |
|---|
| 32 | } |
|---|
| 33 | |
|---|
| 34 | static int nvmem_reboot_mode_probe(struct platform_device *pdev) |
|---|
| 35 | { |
|---|
| 36 | int ret; |
|---|
| 37 | struct nvmem_reboot_mode *nvmem_rbm; |
|---|
| 38 | |
|---|
| 39 | nvmem_rbm = devm_kzalloc(dev: &pdev->dev, size: sizeof(*nvmem_rbm), GFP_KERNEL); |
|---|
| 40 | if (!nvmem_rbm) |
|---|
| 41 | return -ENOMEM; |
|---|
| 42 | |
|---|
| 43 | nvmem_rbm->reboot.dev = &pdev->dev; |
|---|
| 44 | nvmem_rbm->reboot.write = nvmem_reboot_mode_write; |
|---|
| 45 | |
|---|
| 46 | nvmem_rbm->cell = devm_nvmem_cell_get(dev: &pdev->dev, id: "reboot-mode" ); |
|---|
| 47 | if (IS_ERR(ptr: nvmem_rbm->cell)) { |
|---|
| 48 | return dev_err_probe(dev: &pdev->dev, err: PTR_ERR(ptr: nvmem_rbm->cell), |
|---|
| 49 | fmt: "failed to get the nvmem cell reboot-mode\n" ); |
|---|
| 50 | } |
|---|
| 51 | |
|---|
| 52 | ret = devm_reboot_mode_register(dev: &pdev->dev, reboot: &nvmem_rbm->reboot); |
|---|
| 53 | if (ret) |
|---|
| 54 | dev_err(&pdev->dev, "can't register reboot mode\n" ); |
|---|
| 55 | |
|---|
| 56 | return ret; |
|---|
| 57 | } |
|---|
| 58 | |
|---|
| 59 | static const struct of_device_id nvmem_reboot_mode_of_match[] = { |
|---|
| 60 | { .compatible = "nvmem-reboot-mode" }, |
|---|
| 61 | {} |
|---|
| 62 | }; |
|---|
| 63 | MODULE_DEVICE_TABLE(of, nvmem_reboot_mode_of_match); |
|---|
| 64 | |
|---|
| 65 | static struct platform_driver nvmem_reboot_mode_driver = { |
|---|
| 66 | .probe = nvmem_reboot_mode_probe, |
|---|
| 67 | .driver = { |
|---|
| 68 | .name = "nvmem-reboot-mode" , |
|---|
| 69 | .of_match_table = nvmem_reboot_mode_of_match, |
|---|
| 70 | }, |
|---|
| 71 | }; |
|---|
| 72 | module_platform_driver(nvmem_reboot_mode_driver); |
|---|
| 73 | |
|---|
| 74 | MODULE_AUTHOR("Nandor Han <nandor.han@vaisala.com>" ); |
|---|
| 75 | MODULE_DESCRIPTION("NVMEM reboot mode driver" ); |
|---|
| 76 | MODULE_LICENSE("GPL" ); |
|---|
| 77 | |
|---|
