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
dwc3_generic_reset_control_assert(void * data)25 static void dwc3_generic_reset_control_assert(void *data)
26 {
27 reset_control_assert(data);
28 }
29
dwc3_generic_probe(struct platform_device * pdev)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
dwc3_generic_remove(struct platform_device * pdev)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
dwc3_generic_suspend(struct device * dev)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
dwc3_generic_resume(struct device * dev)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
dwc3_generic_runtime_suspend(struct device * dev)124 static int dwc3_generic_runtime_suspend(struct device *dev)
125 {
126 return dwc3_runtime_suspend(dev_get_drvdata(dev));
127 }
128
dwc3_generic_runtime_resume(struct device * dev)129 static int dwc3_generic_runtime_resume(struct device *dev)
130 {
131 return dwc3_runtime_resume(dev_get_drvdata(dev));
132 }
133
dwc3_generic_runtime_idle(struct device * dev)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