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 | |