xref: /linux/drivers/usb/dwc3/dwc3-generic-plat.c (revision 09b1704f5b02c18dd02b21343530463fcfc92c54)
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 
89 	dwc3_core_remove(dwc);
90 }
91 
92 static int dwc3_generic_suspend(struct device *dev)
93 {
94 	struct dwc3 *dwc = dev_get_drvdata(dev);
95 	struct dwc3_generic *dwc3g = to_dwc3_generic(dwc);
96 	int ret;
97 
98 	ret = dwc3_pm_suspend(dwc);
99 	if (ret)
100 		return ret;
101 
102 	clk_bulk_disable_unprepare(dwc3g->num_clocks, dwc3g->clks);
103 
104 	return 0;
105 }
106 
107 static int dwc3_generic_resume(struct device *dev)
108 {
109 	struct dwc3 *dwc = dev_get_drvdata(dev);
110 	struct dwc3_generic *dwc3g = to_dwc3_generic(dwc);
111 	int ret;
112 
113 	ret = clk_bulk_prepare_enable(dwc3g->num_clocks, dwc3g->clks);
114 	if (ret)
115 		return ret;
116 
117 	ret = dwc3_pm_resume(dwc);
118 	if (ret)
119 		return ret;
120 
121 	return 0;
122 }
123 
124 static int dwc3_generic_runtime_suspend(struct device *dev)
125 {
126 	return dwc3_runtime_suspend(dev_get_drvdata(dev));
127 }
128 
129 static int dwc3_generic_runtime_resume(struct device *dev)
130 {
131 	return dwc3_runtime_resume(dev_get_drvdata(dev));
132 }
133 
134 static int dwc3_generic_runtime_idle(struct device *dev)
135 {
136 	return dwc3_runtime_idle(dev_get_drvdata(dev));
137 }
138 
139 static const struct dev_pm_ops dwc3_generic_dev_pm_ops = {
140 	SYSTEM_SLEEP_PM_OPS(dwc3_generic_suspend, dwc3_generic_resume)
141 	RUNTIME_PM_OPS(dwc3_generic_runtime_suspend, dwc3_generic_runtime_resume,
142 		       dwc3_generic_runtime_idle)
143 };
144 
145 static const struct of_device_id dwc3_generic_of_match[] = {
146 	{ .compatible = "spacemit,k1-dwc3", },
147 	{ /* sentinel */ }
148 };
149 MODULE_DEVICE_TABLE(of, dwc3_generic_of_match);
150 
151 static struct platform_driver dwc3_generic_driver = {
152 	.probe		= dwc3_generic_probe,
153 	.remove		= dwc3_generic_remove,
154 	.driver		= {
155 		.name	= "dwc3-generic-plat",
156 		.of_match_table = dwc3_generic_of_match,
157 		.pm	= pm_ptr(&dwc3_generic_dev_pm_ops),
158 	},
159 };
160 module_platform_driver(dwc3_generic_driver);
161 
162 MODULE_LICENSE("GPL");
163 MODULE_DESCRIPTION("DesignWare USB3 generic platform driver");
164