xref: /linux/drivers/usb/dwc3/dwc3-of-simple.c (revision e3b9f1e81de2083f359bacd2a94bf1c024f2ede0)
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_disable_unprepare(simple->clks[i]);
56 				clk_put(simple->clks[i]);
57 			}
58 			return PTR_ERR(clk);
59 		}
60 
61 		ret = clk_prepare_enable(clk);
62 		if (ret < 0) {
63 			while (--i >= 0) {
64 				clk_disable_unprepare(simple->clks[i]);
65 				clk_put(simple->clks[i]);
66 			}
67 			clk_put(clk);
68 
69 			return ret;
70 		}
71 
72 		simple->clks[i] = clk;
73 	}
74 
75 	return 0;
76 }
77 
78 static int dwc3_of_simple_probe(struct platform_device *pdev)
79 {
80 	struct dwc3_of_simple	*simple;
81 	struct device		*dev = &pdev->dev;
82 	struct device_node	*np = dev->of_node;
83 
84 	int			ret;
85 	int			i;
86 
87 	simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
88 	if (!simple)
89 		return -ENOMEM;
90 
91 	platform_set_drvdata(pdev, simple);
92 	simple->dev = dev;
93 
94 	simple->resets = of_reset_control_array_get_optional_exclusive(np);
95 	if (IS_ERR(simple->resets)) {
96 		ret = PTR_ERR(simple->resets);
97 		dev_err(dev, "failed to get device resets, err=%d\n", ret);
98 		return ret;
99 	}
100 
101 	ret = reset_control_deassert(simple->resets);
102 	if (ret)
103 		goto err_resetc_put;
104 
105 	ret = dwc3_of_simple_clk_init(simple, of_count_phandle_with_args(np,
106 						"clocks", "#clock-cells"));
107 	if (ret)
108 		goto err_resetc_assert;
109 
110 	ret = of_platform_populate(np, NULL, NULL, dev);
111 	if (ret) {
112 		for (i = 0; i < simple->num_clocks; i++) {
113 			clk_disable_unprepare(simple->clks[i]);
114 			clk_put(simple->clks[i]);
115 		}
116 
117 		goto err_resetc_assert;
118 	}
119 
120 	pm_runtime_set_active(dev);
121 	pm_runtime_enable(dev);
122 	pm_runtime_get_sync(dev);
123 
124 	return 0;
125 
126 err_resetc_assert:
127 	reset_control_assert(simple->resets);
128 
129 err_resetc_put:
130 	reset_control_put(simple->resets);
131 	return ret;
132 }
133 
134 static int dwc3_of_simple_remove(struct platform_device *pdev)
135 {
136 	struct dwc3_of_simple	*simple = platform_get_drvdata(pdev);
137 	struct device		*dev = &pdev->dev;
138 	int			i;
139 
140 	of_platform_depopulate(dev);
141 
142 	for (i = 0; i < simple->num_clocks; i++) {
143 		clk_disable_unprepare(simple->clks[i]);
144 		clk_put(simple->clks[i]);
145 	}
146 	simple->num_clocks = 0;
147 
148 	reset_control_assert(simple->resets);
149 	reset_control_put(simple->resets);
150 
151 	pm_runtime_put_sync(dev);
152 	pm_runtime_disable(dev);
153 
154 	return 0;
155 }
156 
157 #ifdef CONFIG_PM
158 static int dwc3_of_simple_runtime_suspend(struct device *dev)
159 {
160 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
161 	int			i;
162 
163 	for (i = 0; i < simple->num_clocks; i++)
164 		clk_disable(simple->clks[i]);
165 
166 	return 0;
167 }
168 
169 static int dwc3_of_simple_runtime_resume(struct device *dev)
170 {
171 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
172 	int			ret;
173 	int			i;
174 
175 	for (i = 0; i < simple->num_clocks; i++) {
176 		ret = clk_enable(simple->clks[i]);
177 		if (ret < 0) {
178 			while (--i >= 0)
179 				clk_disable(simple->clks[i]);
180 			return ret;
181 		}
182 	}
183 
184 	return 0;
185 }
186 #endif
187 
188 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
189 	SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
190 			dwc3_of_simple_runtime_resume, NULL)
191 };
192 
193 static const struct of_device_id of_dwc3_simple_match[] = {
194 	{ .compatible = "qcom,dwc3" },
195 	{ .compatible = "rockchip,rk3399-dwc3" },
196 	{ .compatible = "xlnx,zynqmp-dwc3" },
197 	{ .compatible = "cavium,octeon-7130-usb-uctl" },
198 	{ .compatible = "sprd,sc9860-dwc3" },
199 	{ /* Sentinel */ }
200 };
201 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
202 
203 static struct platform_driver dwc3_of_simple_driver = {
204 	.probe		= dwc3_of_simple_probe,
205 	.remove		= dwc3_of_simple_remove,
206 	.driver		= {
207 		.name	= "dwc3-of-simple",
208 		.of_match_table = of_dwc3_simple_match,
209 		.pm	= &dwc3_of_simple_dev_pm_ops,
210 	},
211 };
212 
213 module_platform_driver(dwc3_of_simple_driver);
214 MODULE_LICENSE("GPL v2");
215 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
216 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
217