1 // SPDX-License-Identifier: GPL-2.0
2 /**
3  * dwc3-of-simple.c - OF glue layer for simple integrations
4  *
5  * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
6  *
7  * Author: Felipe Balbi <balbi@ti.com>
8  *
9  * This is a combination of the old dwc3-qcom.c by Ivan T. Ivanov
10  * <iivanov@mm-sol.com> and the original patch adding support for Xilinx' SoC
11  * by Subbaraya Sundeep Bhatta <subbaraya.sundeep.bhatta@xilinx.com>
12  */
13 
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/platform_device.h>
18 #include <linux/dma-mapping.h>
19 #include <linux/clk.h>
20 #include <linux/of.h>
21 #include <linux/of_platform.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/reset.h>
24 
25 struct dwc3_of_simple {
26 	struct device		*dev;
27 	struct clk		**clks;
28 	int			num_clocks;
29 	struct reset_control	*resets;
30 };
31 
32 static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count)
33 {
34 	struct device		*dev = simple->dev;
35 	struct device_node	*np = dev->of_node;
36 	int			i;
37 
38 	simple->num_clocks = count;
39 
40 	if (!count)
41 		return 0;
42 
43 	simple->clks = devm_kcalloc(dev, simple->num_clocks,
44 			sizeof(struct clk *), GFP_KERNEL);
45 	if (!simple->clks)
46 		return -ENOMEM;
47 
48 	for (i = 0; i < simple->num_clocks; i++) {
49 		struct clk	*clk;
50 		int		ret;
51 
52 		clk = of_clk_get(np, i);
53 		if (IS_ERR(clk)) {
54 			while (--i >= 0)
55 				clk_put(simple->clks[i]);
56 			return PTR_ERR(clk);
57 		}
58 
59 		ret = clk_prepare_enable(clk);
60 		if (ret < 0) {
61 			while (--i >= 0) {
62 				clk_disable_unprepare(simple->clks[i]);
63 				clk_put(simple->clks[i]);
64 			}
65 			clk_put(clk);
66 
67 			return ret;
68 		}
69 
70 		simple->clks[i] = clk;
71 	}
72 
73 	return 0;
74 }
75 
76 static int dwc3_of_simple_probe(struct platform_device *pdev)
77 {
78 	struct dwc3_of_simple	*simple;
79 	struct device		*dev = &pdev->dev;
80 	struct device_node	*np = dev->of_node;
81 
82 	int			ret;
83 	int			i;
84 
85 	simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
86 	if (!simple)
87 		return -ENOMEM;
88 
89 	platform_set_drvdata(pdev, simple);
90 	simple->dev = dev;
91 
92 	simple->resets = of_reset_control_array_get_optional_exclusive(np);
93 	if (IS_ERR(simple->resets)) {
94 		ret = PTR_ERR(simple->resets);
95 		dev_err(dev, "failed to get device resets, err=%d\n", ret);
96 		return ret;
97 	}
98 
99 	ret = reset_control_deassert(simple->resets);
100 	if (ret)
101 		goto err_resetc_put;
102 
103 	ret = dwc3_of_simple_clk_init(simple, of_count_phandle_with_args(np,
104 						"clocks", "#clock-cells"));
105 	if (ret)
106 		goto err_resetc_assert;
107 
108 	ret = of_platform_populate(np, NULL, NULL, dev);
109 	if (ret) {
110 		for (i = 0; i < simple->num_clocks; i++) {
111 			clk_disable_unprepare(simple->clks[i]);
112 			clk_put(simple->clks[i]);
113 		}
114 
115 		goto err_resetc_assert;
116 	}
117 
118 	pm_runtime_set_active(dev);
119 	pm_runtime_enable(dev);
120 	pm_runtime_get_sync(dev);
121 
122 	return 0;
123 
124 err_resetc_assert:
125 	reset_control_assert(simple->resets);
126 
127 err_resetc_put:
128 	reset_control_put(simple->resets);
129 	return ret;
130 }
131 
132 static int dwc3_of_simple_remove(struct platform_device *pdev)
133 {
134 	struct dwc3_of_simple	*simple = platform_get_drvdata(pdev);
135 	struct device		*dev = &pdev->dev;
136 	int			i;
137 
138 	of_platform_depopulate(dev);
139 
140 	for (i = 0; i < simple->num_clocks; i++) {
141 		clk_disable_unprepare(simple->clks[i]);
142 		clk_put(simple->clks[i]);
143 	}
144 
145 	reset_control_assert(simple->resets);
146 	reset_control_put(simple->resets);
147 
148 	pm_runtime_put_sync(dev);
149 	pm_runtime_disable(dev);
150 
151 	return 0;
152 }
153 
154 #ifdef CONFIG_PM
155 static int dwc3_of_simple_runtime_suspend(struct device *dev)
156 {
157 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
158 	int			i;
159 
160 	for (i = 0; i < simple->num_clocks; i++)
161 		clk_disable(simple->clks[i]);
162 
163 	return 0;
164 }
165 
166 static int dwc3_of_simple_runtime_resume(struct device *dev)
167 {
168 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
169 	int			ret;
170 	int			i;
171 
172 	for (i = 0; i < simple->num_clocks; i++) {
173 		ret = clk_enable(simple->clks[i]);
174 		if (ret < 0) {
175 			while (--i >= 0)
176 				clk_disable(simple->clks[i]);
177 			return ret;
178 		}
179 	}
180 
181 	return 0;
182 }
183 #endif
184 
185 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
186 	SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
187 			dwc3_of_simple_runtime_resume, NULL)
188 };
189 
190 static const struct of_device_id of_dwc3_simple_match[] = {
191 	{ .compatible = "qcom,dwc3" },
192 	{ .compatible = "rockchip,rk3399-dwc3" },
193 	{ .compatible = "xlnx,zynqmp-dwc3" },
194 	{ .compatible = "cavium,octeon-7130-usb-uctl" },
195 	{ .compatible = "sprd,sc9860-dwc3" },
196 	{ /* Sentinel */ }
197 };
198 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
199 
200 static struct platform_driver dwc3_of_simple_driver = {
201 	.probe		= dwc3_of_simple_probe,
202 	.remove		= dwc3_of_simple_remove,
203 	.driver		= {
204 		.name	= "dwc3-of-simple",
205 		.of_match_table = of_dwc3_simple_match,
206 	},
207 };
208 
209 module_platform_driver(dwc3_of_simple_driver);
210 MODULE_LICENSE("GPL v2");
211 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
212 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
213