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6#include <linux/kernel.h>
7#include <linux/mfd/syscon.h>
8#include <linux/module.h>
9#include <linux/of_device.h>
10#include <linux/platform_device.h>
11#include <linux/regmap.h>
12#include <linux/reset-controller.h>
13
14struct hi3660_reset_controller {
15 struct reset_controller_dev rst;
16 struct regmap *map;
17};
18
19#define to_hi3660_reset_controller(_rst) \
20 container_of(_rst, struct hi3660_reset_controller, rst)
21
22static int hi3660_reset_program_hw(struct reset_controller_dev *rcdev,
23 unsigned long idx, bool assert)
24{
25 struct hi3660_reset_controller *rc = to_hi3660_reset_controller(rcdev);
26 unsigned int offset = idx >> 8;
27 unsigned int mask = BIT(idx & 0x1f);
28
29 if (assert)
30 return regmap_write(rc->map, offset, mask);
31 else
32 return regmap_write(rc->map, offset + 4, mask);
33}
34
35static int hi3660_reset_assert(struct reset_controller_dev *rcdev,
36 unsigned long idx)
37{
38 return hi3660_reset_program_hw(rcdev, idx, true);
39}
40
41static int hi3660_reset_deassert(struct reset_controller_dev *rcdev,
42 unsigned long idx)
43{
44 return hi3660_reset_program_hw(rcdev, idx, false);
45}
46
47static int hi3660_reset_dev(struct reset_controller_dev *rcdev,
48 unsigned long idx)
49{
50 int err;
51
52 err = hi3660_reset_assert(rcdev, idx);
53 if (err)
54 return err;
55
56 return hi3660_reset_deassert(rcdev, idx);
57}
58
59static struct reset_control_ops hi3660_reset_ops = {
60 .reset = hi3660_reset_dev,
61 .assert = hi3660_reset_assert,
62 .deassert = hi3660_reset_deassert,
63};
64
65static int hi3660_reset_xlate(struct reset_controller_dev *rcdev,
66 const struct of_phandle_args *reset_spec)
67{
68 unsigned int offset, bit;
69
70 offset = reset_spec->args[0];
71 bit = reset_spec->args[1];
72
73 return (offset << 8) | bit;
74}
75
76static int hi3660_reset_probe(struct platform_device *pdev)
77{
78 struct hi3660_reset_controller *rc;
79 struct device_node *np = pdev->dev.of_node;
80 struct device *dev = &pdev->dev;
81
82 rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL);
83 if (!rc)
84 return -ENOMEM;
85
86 rc->map = syscon_regmap_lookup_by_phandle(np, "hisi,rst-syscon");
87 if (IS_ERR(rc->map)) {
88 dev_err(dev, "failed to get hi3660,rst-syscon\n");
89 return PTR_ERR(rc->map);
90 }
91
92 rc->rst.ops = &hi3660_reset_ops,
93 rc->rst.of_node = np;
94 rc->rst.of_reset_n_cells = 2;
95 rc->rst.of_xlate = hi3660_reset_xlate;
96
97 return reset_controller_register(&rc->rst);
98}
99
100static const struct of_device_id hi3660_reset_match[] = {
101 { .compatible = "hisilicon,hi3660-reset", },
102 {},
103};
104MODULE_DEVICE_TABLE(of, hi3660_reset_match);
105
106static struct platform_driver hi3660_reset_driver = {
107 .probe = hi3660_reset_probe,
108 .driver = {
109 .name = "hi3660-reset",
110 .of_match_table = hi3660_reset_match,
111 },
112};
113
114static int __init hi3660_reset_init(void)
115{
116 return platform_driver_register(&hi3660_reset_driver);
117}
118arch_initcall(hi3660_reset_init);
119
120MODULE_LICENSE("GPL");
121MODULE_ALIAS("platform:hi3660-reset");
122MODULE_DESCRIPTION("HiSilicon Hi3660 Reset Driver");
123
