xref: /linux/drivers/usb/dwc3/dwc3-generic-plat.c (revision 6093a688a07da07808f0122f9aa2a3eed250d853)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * dwc3-generic-plat.c - DesignWare USB3 generic platform driver
4  *
5  * Copyright (C) 2025 Ze Huang <huang.ze@linux.dev>
6  *
7  * Inspired by dwc3-qcom.c and dwc3-of-simple.c
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/platform_device.h>
12 #include <linux/reset.h>
13 #include "glue.h"
14 
15 struct dwc3_generic {
16 	struct device		*dev;
17 	struct dwc3		dwc;
18 	struct clk_bulk_data	*clks;
19 	int			num_clocks;
20 	struct reset_control	*resets;
21 };
22 
23 #define to_dwc3_generic(d) container_of((d), struct dwc3_generic, dwc)
24 
25 static void dwc3_generic_reset_control_assert(void *data)
26 {
27 	reset_control_assert(data);
28 }
29 
30 static int dwc3_generic_probe(struct platform_device *pdev)
31 {
32 	struct dwc3_probe_data probe_data = {};
33 	struct device *dev = &pdev->dev;
34 	struct dwc3_generic *dwc3g;
35 	struct resource *res;
36 	int ret;
37 
38 	dwc3g = devm_kzalloc(dev, sizeof(*dwc3g), GFP_KERNEL);
39 	if (!dwc3g)
40 		return -ENOMEM;
41 
42 	dwc3g->dev = dev;
43 
44 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
45 	if (!res) {
46 		dev_err(&pdev->dev, "missing memory resource\n");
47 		return -ENODEV;
48 	}
49 
50 	dwc3g->resets = devm_reset_control_array_get_optional_exclusive(dev);
51 	if (IS_ERR(dwc3g->resets))
52 		return dev_err_probe(dev, PTR_ERR(dwc3g->resets), "failed to get resets\n");
53 
54 	ret = reset_control_assert(dwc3g->resets);
55 	if (ret)
56 		return dev_err_probe(dev, ret, "failed to assert resets\n");
57 
58 	/* Not strict timing, just for safety */
59 	udelay(2);
60 
61 	ret = reset_control_deassert(dwc3g->resets);
62 	if (ret)
63 		return dev_err_probe(dev, ret, "failed to deassert resets\n");
64 
65 	ret = devm_add_action_or_reset(dev, dwc3_generic_reset_control_assert, dwc3g->resets);
66 	if (ret)
67 		return ret;
68 
69 	ret = devm_clk_bulk_get_all_enabled(dwc3g->dev, &dwc3g->clks);
70 	if (ret < 0)
71 		return dev_err_probe(dev, ret, "failed to get clocks\n");
72 
73 	dwc3g->num_clocks = ret;
74 	dwc3g->dwc.dev = dev;
75 	probe_data.dwc = &dwc3g->dwc;
76 	probe_data.res = res;
77 	probe_data.ignore_clocks_and_resets = true;
78 	ret = dwc3_core_probe(&probe_data);
79 	if (ret)
80 		return dev_err_probe(dev, ret, "failed to register DWC3 Core\n");
81 
82 	return 0;
83 }
84 
85 static void dwc3_generic_remove(struct platform_device *pdev)
86 {
87 	struct dwc3 *dwc = platform_get_drvdata(pdev);
88 	struct dwc3_generic *dwc3g = to_dwc3_generic(dwc);
89 
90 	dwc3_core_remove(dwc);
91 
92 	clk_bulk_disable_unprepare(dwc3g->num_clocks, dwc3g->clks);
93 }
94 
95 static int dwc3_generic_suspend(struct device *dev)
96 {
97 	struct dwc3 *dwc = dev_get_drvdata(dev);
98 	struct dwc3_generic *dwc3g = to_dwc3_generic(dwc);
99 	int ret;
100 
101 	ret = dwc3_pm_suspend(dwc);
102 	if (ret)
103 		return ret;
104 
105 	clk_bulk_disable_unprepare(dwc3g->num_clocks, dwc3g->clks);
106 
107 	return 0;
108 }
109 
110 static int dwc3_generic_resume(struct device *dev)
111 {
112 	struct dwc3 *dwc = dev_get_drvdata(dev);
113 	struct dwc3_generic *dwc3g = to_dwc3_generic(dwc);
114 	int ret;
115 
116 	ret = clk_bulk_prepare_enable(dwc3g->num_clocks, dwc3g->clks);
117 	if (ret)
118 		return ret;
119 
120 	ret = dwc3_pm_resume(dwc);
121 	if (ret)
122 		return ret;
123 
124 	return 0;
125 }
126 
127 static int dwc3_generic_runtime_suspend(struct device *dev)
128 {
129 	return dwc3_runtime_suspend(dev_get_drvdata(dev));
130 }
131 
132 static int dwc3_generic_runtime_resume(struct device *dev)
133 {
134 	return dwc3_runtime_resume(dev_get_drvdata(dev));
135 }
136 
137 static int dwc3_generic_runtime_idle(struct device *dev)
138 {
139 	return dwc3_runtime_idle(dev_get_drvdata(dev));
140 }
141 
142 static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
143 	SYSTEM_SLEEP_PM_OPS(dwc3_generic_suspend, dwc3_generic_resume)
144 	RUNTIME_PM_OPS(dwc3_generic_runtime_suspend, dwc3_generic_runtime_resume,
145 		       dwc3_generic_runtime_idle)
146 };
147 
148 static const struct of_device_id dwc3_generic_of_match[] = {
149 	{ .compatible = "spacemit,k1-dwc3", },
150 	{ /* sentinel */ }
151 };
152 MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
153 
154 static struct platform_driver dwc3_generic_driver = {
155 	.probe		= dwc3_generic_probe,
156 	.remove		= dwc3_generic_remove,
157 	.driver		= {
158 		.name	= "dwc3-generic-plat",
159 		.of_match_table = dwc3_generic_of_match,
160 		.pm	= pm_ptr(&dwc3_generic_dev_pm_ops),
161 	},
162 };
163 module_platform_driver(dwc3_generic_driver);
164 
165 MODULE_LICENSE("GPL");
166 MODULE_DESCRIPTION("DesignWare USB3 generic platform driver");
167