1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd |
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/platform_device.h> |
11 | #include <linux/reboot.h> |
12 | #include <linux/regmap.h> |
13 | #include <linux/mfd/syscon.h> |
14 | #include <linux/reboot-mode.h> |
15 | |
16 | struct syscon_reboot_mode { |
17 | struct regmap *map; |
18 | struct reboot_mode_driver reboot; |
19 | u32 offset; |
20 | u32 mask; |
21 | }; |
22 | |
23 | static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot, |
24 | unsigned int magic) |
25 | { |
26 | struct syscon_reboot_mode *syscon_rbm; |
27 | int ret; |
28 | |
29 | syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot); |
30 | |
31 | ret = regmap_update_bits(map: syscon_rbm->map, reg: syscon_rbm->offset, |
32 | mask: syscon_rbm->mask, val: magic); |
33 | if (ret < 0) |
34 | dev_err(reboot->dev, "update reboot mode bits failed\n" ); |
35 | |
36 | return ret; |
37 | } |
38 | |
39 | static int syscon_reboot_mode_probe(struct platform_device *pdev) |
40 | { |
41 | int ret; |
42 | struct syscon_reboot_mode *syscon_rbm; |
43 | |
44 | syscon_rbm = devm_kzalloc(dev: &pdev->dev, size: sizeof(*syscon_rbm), GFP_KERNEL); |
45 | if (!syscon_rbm) |
46 | return -ENOMEM; |
47 | |
48 | syscon_rbm->reboot.dev = &pdev->dev; |
49 | syscon_rbm->reboot.write = syscon_reboot_mode_write; |
50 | syscon_rbm->mask = 0xffffffff; |
51 | |
52 | syscon_rbm->map = syscon_node_to_regmap(np: pdev->dev.parent->of_node); |
53 | if (IS_ERR(ptr: syscon_rbm->map)) |
54 | return PTR_ERR(ptr: syscon_rbm->map); |
55 | |
56 | if (of_property_read_u32(np: pdev->dev.of_node, propname: "offset" , |
57 | out_value: &syscon_rbm->offset)) |
58 | return -EINVAL; |
59 | |
60 | of_property_read_u32(np: pdev->dev.of_node, propname: "mask" , out_value: &syscon_rbm->mask); |
61 | |
62 | ret = devm_reboot_mode_register(dev: &pdev->dev, reboot: &syscon_rbm->reboot); |
63 | if (ret) |
64 | dev_err(&pdev->dev, "can't register reboot mode\n" ); |
65 | |
66 | return ret; |
67 | } |
68 | |
69 | static const struct of_device_id syscon_reboot_mode_of_match[] = { |
70 | { .compatible = "syscon-reboot-mode" }, |
71 | {} |
72 | }; |
73 | MODULE_DEVICE_TABLE(of, syscon_reboot_mode_of_match); |
74 | |
75 | static struct platform_driver syscon_reboot_mode_driver = { |
76 | .probe = syscon_reboot_mode_probe, |
77 | .driver = { |
78 | .name = "syscon-reboot-mode" , |
79 | .of_match_table = syscon_reboot_mode_of_match, |
80 | }, |
81 | }; |
82 | module_platform_driver(syscon_reboot_mode_driver); |
83 | |
84 | MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com" ); |
85 | MODULE_DESCRIPTION("SYSCON reboot mode driver" ); |
86 | MODULE_LICENSE("GPL v2" ); |
87 | |