1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
4*4882a593Smuzhiyun */
5*4882a593Smuzhiyun
6*4882a593Smuzhiyun #include <linux/init.h>
7*4882a593Smuzhiyun #include <linux/module.h>
8*4882a593Smuzhiyun #include <linux/kernel.h>
9*4882a593Smuzhiyun #include <linux/of.h>
10*4882a593Smuzhiyun #include <linux/platform_device.h>
11*4882a593Smuzhiyun #include <linux/reboot.h>
12*4882a593Smuzhiyun #include <linux/regmap.h>
13*4882a593Smuzhiyun #include <linux/mfd/syscon.h>
14*4882a593Smuzhiyun #include <linux/reboot-mode.h>
15*4882a593Smuzhiyun
16*4882a593Smuzhiyun struct syscon_reboot_mode {
17*4882a593Smuzhiyun struct regmap *map;
18*4882a593Smuzhiyun struct reboot_mode_driver reboot;
19*4882a593Smuzhiyun u32 offset;
20*4882a593Smuzhiyun u32 mask;
21*4882a593Smuzhiyun };
22*4882a593Smuzhiyun
syscon_reboot_mode_write(struct reboot_mode_driver * reboot,unsigned int magic)23*4882a593Smuzhiyun static int syscon_reboot_mode_write(struct reboot_mode_driver *reboot,
24*4882a593Smuzhiyun unsigned int magic)
25*4882a593Smuzhiyun {
26*4882a593Smuzhiyun struct syscon_reboot_mode *syscon_rbm;
27*4882a593Smuzhiyun int ret;
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot);
30*4882a593Smuzhiyun
31*4882a593Smuzhiyun ret = regmap_update_bits(syscon_rbm->map, syscon_rbm->offset,
32*4882a593Smuzhiyun syscon_rbm->mask, magic);
33*4882a593Smuzhiyun if (ret < 0)
34*4882a593Smuzhiyun dev_err(reboot->dev, "update reboot mode bits failed\n");
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun return ret;
37*4882a593Smuzhiyun }
38*4882a593Smuzhiyun
syscon_reboot_mode_read(struct reboot_mode_driver * reboot)39*4882a593Smuzhiyun static int syscon_reboot_mode_read(struct reboot_mode_driver *reboot)
40*4882a593Smuzhiyun {
41*4882a593Smuzhiyun struct syscon_reboot_mode *syscon_rbm;
42*4882a593Smuzhiyun u32 val = 0;
43*4882a593Smuzhiyun
44*4882a593Smuzhiyun syscon_rbm = container_of(reboot, struct syscon_reboot_mode, reboot);
45*4882a593Smuzhiyun regmap_read(syscon_rbm->map, syscon_rbm->offset, &val);
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun return val;
48*4882a593Smuzhiyun }
49*4882a593Smuzhiyun
syscon_reboot_mode_probe(struct platform_device * pdev)50*4882a593Smuzhiyun static int syscon_reboot_mode_probe(struct platform_device *pdev)
51*4882a593Smuzhiyun {
52*4882a593Smuzhiyun int ret;
53*4882a593Smuzhiyun struct syscon_reboot_mode *syscon_rbm;
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun syscon_rbm = devm_kzalloc(&pdev->dev, sizeof(*syscon_rbm), GFP_KERNEL);
56*4882a593Smuzhiyun if (!syscon_rbm)
57*4882a593Smuzhiyun return -ENOMEM;
58*4882a593Smuzhiyun
59*4882a593Smuzhiyun syscon_rbm->reboot.dev = &pdev->dev;
60*4882a593Smuzhiyun syscon_rbm->reboot.write = syscon_reboot_mode_write;
61*4882a593Smuzhiyun syscon_rbm->reboot.read = syscon_reboot_mode_read;
62*4882a593Smuzhiyun syscon_rbm->mask = 0xffffffff;
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun syscon_rbm->map = syscon_node_to_regmap(pdev->dev.parent->of_node);
65*4882a593Smuzhiyun if (IS_ERR(syscon_rbm->map))
66*4882a593Smuzhiyun return PTR_ERR(syscon_rbm->map);
67*4882a593Smuzhiyun
68*4882a593Smuzhiyun if (of_property_read_u32(pdev->dev.of_node, "offset",
69*4882a593Smuzhiyun &syscon_rbm->offset))
70*4882a593Smuzhiyun return -EINVAL;
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun of_property_read_u32(pdev->dev.of_node, "mask", &syscon_rbm->mask);
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun ret = devm_reboot_mode_register(&pdev->dev, &syscon_rbm->reboot);
75*4882a593Smuzhiyun if (ret)
76*4882a593Smuzhiyun dev_err(&pdev->dev, "can't register reboot mode\n");
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun return ret;
79*4882a593Smuzhiyun }
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun static const struct of_device_id syscon_reboot_mode_of_match[] = {
82*4882a593Smuzhiyun { .compatible = "syscon-reboot-mode" },
83*4882a593Smuzhiyun {}
84*4882a593Smuzhiyun };
85*4882a593Smuzhiyun MODULE_DEVICE_TABLE(of, syscon_reboot_mode_of_match);
86*4882a593Smuzhiyun
87*4882a593Smuzhiyun static struct platform_driver syscon_reboot_mode_driver = {
88*4882a593Smuzhiyun .probe = syscon_reboot_mode_probe,
89*4882a593Smuzhiyun .driver = {
90*4882a593Smuzhiyun .name = "syscon-reboot-mode",
91*4882a593Smuzhiyun .of_match_table = syscon_reboot_mode_of_match,
92*4882a593Smuzhiyun },
93*4882a593Smuzhiyun };
94*4882a593Smuzhiyun module_platform_driver(syscon_reboot_mode_driver);
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun MODULE_AUTHOR("Andy Yan <andy.yan@rock-chips.com");
97*4882a593Smuzhiyun MODULE_DESCRIPTION("SYSCON reboot mode driver");
98*4882a593Smuzhiyun MODULE_LICENSE("GPL v2");
99