xref: /linux/drivers/reset/reset-eic7700-hsp.c (revision b37fe0ee3691b9da358cdfbbdad67874e562ac90)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2026, Beijing ESWIN Computing Technology Co., Ltd..
4  * All rights reserved.
5  *
6  * ESWIN EIC7700 HSP Reset Driver
7  *
8  * Authors: Xuyang Dong <dongxuyang@eswincomputing.com>
9  */
10 
11 #include <linux/auxiliary_bus.h>
12 #include <linux/device.h>
13 #include <linux/module.h>
14 #include <linux/regmap.h>
15 #include <linux/reset-controller.h>
16 
17 #include <dt-bindings/reset/eswin,eic7700-hspcrg.h>
18 
19 /**
20  * struct eic7700_hsp_reset_data - reset controller information structure
21  * @rcdev: reset controller entity
22  * @regmap: regmap handle containing the memory-mapped reset registers
23  */
24 struct eic7700_hsp_reset_data {
25 	struct reset_controller_dev rcdev;
26 	struct regmap *regmap;
27 };
28 
29 struct eic7700_hsp_reg {
30 	u32 reg;
31 	u32 bit;
32 	bool active_low;
33 };
34 
35 static inline struct eic7700_hsp_reset_data *
36 to_eic7700_hsp_reset(struct reset_controller_dev *rcdev)
37 {
38 	return container_of(rcdev, struct eic7700_hsp_reset_data, rcdev);
39 }
40 
41 static const struct eic7700_hsp_reg eic7700_hsp_reset[] = {
42 	[EIC7700_HSP_RST_SATA_P0]	= {0x340, BIT(0), false},
43 	[EIC7700_HSP_RST_SATA_PHY]	= {0x340, BIT(1), false},
44 	[EIC7700_HSP_RST_USB0]		= {0x800, BIT(24), true},
45 	[EIC7700_HSP_RST_USB1]		= {0x900, BIT(24), true},
46 	[EIC7700_HSP_RST_USB0_PHY]	= {0x800, BIT(25), false},
47 	[EIC7700_HSP_RST_USB1_PHY]	= {0x900, BIT(25), false},
48 };
49 
50 static int eic7700_hsp_reset_assert(struct reset_controller_dev *rcdev,
51 				    unsigned long id)
52 {
53 	struct eic7700_hsp_reset_data *data = to_eic7700_hsp_reset(rcdev);
54 
55 	return regmap_assign_bits(data->regmap, eic7700_hsp_reset[id].reg,
56 				  eic7700_hsp_reset[id].bit,
57 				  !eic7700_hsp_reset[id].active_low);
58 }
59 
60 static int eic7700_hsp_reset_deassert(struct reset_controller_dev *rcdev,
61 				      unsigned long id)
62 {
63 	struct eic7700_hsp_reset_data *data = to_eic7700_hsp_reset(rcdev);
64 
65 	return regmap_assign_bits(data->regmap, eic7700_hsp_reset[id].reg,
66 				  eic7700_hsp_reset[id].bit,
67 				  eic7700_hsp_reset[id].active_low);
68 }
69 
70 static const struct reset_control_ops eic7700_hsp_reset_ops = {
71 	.assert = eic7700_hsp_reset_assert,
72 	.deassert = eic7700_hsp_reset_deassert,
73 };
74 
75 static int eic7700_hsp_reset_probe(struct auxiliary_device *adev,
76 				   const struct auxiliary_device_id *id)
77 {
78 	struct eic7700_hsp_reset_data *data;
79 	struct device *dev = &adev->dev;
80 
81 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
82 	if (!data)
83 		return -ENOMEM;
84 
85 	data->regmap = dev_get_regmap(dev->parent, NULL);
86 	if (!data->regmap)
87 		return dev_err_probe(dev, -ENODEV, "failed to get regmap!\n");
88 
89 	data->rcdev.owner = THIS_MODULE;
90 	data->rcdev.ops = &eic7700_hsp_reset_ops;
91 	data->rcdev.of_node = dev->parent->of_node;
92 	data->rcdev.dev = dev;
93 	data->rcdev.nr_resets = ARRAY_SIZE(eic7700_hsp_reset);
94 
95 	return devm_reset_controller_register(dev, &data->rcdev);
96 }
97 
98 static const struct auxiliary_device_id eic7700_hsp_reset_ids[] = {
99 	{ .name = "clk_eic7700_hsp.hsp-reset", },
100 	{ /* sentinel */ }
101 };
102 MODULE_DEVICE_TABLE(auxiliary, eic7700_hsp_reset_ids);
103 
104 static struct auxiliary_driver eic7700_hsp_reset_driver = {
105 	.probe	= eic7700_hsp_reset_probe,
106 	.id_table = eic7700_hsp_reset_ids,
107 };
108 
109 module_auxiliary_driver(eic7700_hsp_reset_driver);
110 
111 MODULE_LICENSE("GPL");
112 MODULE_AUTHOR("Xuyang Dong <dongxuyang@eswincomputing.com>");
113 MODULE_DESCRIPTION("ESWIN EIC7700 HSP Reset Controller Driver");
114