1 /**
2  * dwc3-of-simple.c - OF glue layer for simple integrations
3  *
4  * Copyright (c) 2015 Texas Instruments Incorporated - http://www.ti.com
5  *
6  * Author: Felipe Balbi <balbi@ti.com>
7  *
8  * This program is free software: you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2  of
10  * the License as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * This is a combination of the old dwc3-qcom.c by Ivan T. Ivanov
18  * <iivanov@mm-sol.com> and the original patch adding support for Xilinx' SoC
19  * by Subbaraya Sundeep Bhatta <subbaraya.sundeep.bhatta@xilinx.com>
20  */
21 
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/slab.h>
25 #include <linux/platform_device.h>
26 #include <linux/dma-mapping.h>
27 #include <linux/clk.h>
28 #include <linux/of.h>
29 #include <linux/of_platform.h>
30 #include <linux/pm_runtime.h>
31 
32 struct dwc3_of_simple {
33 	struct device		*dev;
34 	struct clk		**clks;
35 	int			num_clocks;
36 };
37 
38 static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count)
39 {
40 	struct device		*dev = simple->dev;
41 	struct device_node	*np = dev->of_node;
42 	int			i;
43 
44 	simple->num_clocks = count;
45 
46 	if (!count)
47 		return 0;
48 
49 	simple->clks = devm_kcalloc(dev, simple->num_clocks,
50 			sizeof(struct clk *), GFP_KERNEL);
51 	if (!simple->clks)
52 		return -ENOMEM;
53 
54 	for (i = 0; i < simple->num_clocks; i++) {
55 		struct clk	*clk;
56 		int		ret;
57 
58 		clk = of_clk_get(np, i);
59 		if (IS_ERR(clk)) {
60 			while (--i >= 0)
61 				clk_put(simple->clks[i]);
62 			return PTR_ERR(clk);
63 		}
64 
65 		ret = clk_prepare_enable(clk);
66 		if (ret < 0) {
67 			while (--i >= 0) {
68 				clk_disable_unprepare(simple->clks[i]);
69 				clk_put(simple->clks[i]);
70 			}
71 			clk_put(clk);
72 
73 			return ret;
74 		}
75 
76 		simple->clks[i] = clk;
77 	}
78 
79 	return 0;
80 }
81 
82 static int dwc3_of_simple_probe(struct platform_device *pdev)
83 {
84 	struct dwc3_of_simple	*simple;
85 	struct device		*dev = &pdev->dev;
86 	struct device_node	*np = dev->of_node;
87 
88 	int			ret;
89 	int			i;
90 
91 	simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
92 	if (!simple)
93 		return -ENOMEM;
94 
95 	platform_set_drvdata(pdev, simple);
96 	simple->dev = dev;
97 
98 	ret = dwc3_of_simple_clk_init(simple, of_count_phandle_with_args(np,
99 						"clocks", "#clock-cells"));
100 	if (ret)
101 		return ret;
102 
103 	ret = of_platform_populate(np, NULL, NULL, dev);
104 	if (ret) {
105 		for (i = 0; i < simple->num_clocks; i++) {
106 			clk_disable_unprepare(simple->clks[i]);
107 			clk_put(simple->clks[i]);
108 		}
109 
110 		return ret;
111 	}
112 
113 	pm_runtime_set_active(dev);
114 	pm_runtime_enable(dev);
115 	pm_runtime_get_sync(dev);
116 
117 	return 0;
118 }
119 
120 static int dwc3_of_simple_remove(struct platform_device *pdev)
121 {
122 	struct dwc3_of_simple	*simple = platform_get_drvdata(pdev);
123 	struct device		*dev = &pdev->dev;
124 	int			i;
125 
126 	for (i = 0; i < simple->num_clocks; i++) {
127 		clk_disable_unprepare(simple->clks[i]);
128 		clk_put(simple->clks[i]);
129 	}
130 
131 	of_platform_depopulate(dev);
132 
133 	pm_runtime_put_sync(dev);
134 	pm_runtime_disable(dev);
135 
136 	return 0;
137 }
138 
139 #ifdef CONFIG_PM
140 static int dwc3_of_simple_runtime_suspend(struct device *dev)
141 {
142 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
143 	int			i;
144 
145 	for (i = 0; i < simple->num_clocks; i++)
146 		clk_disable(simple->clks[i]);
147 
148 	return 0;
149 }
150 
151 static int dwc3_of_simple_runtime_resume(struct device *dev)
152 {
153 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
154 	int			ret;
155 	int			i;
156 
157 	for (i = 0; i < simple->num_clocks; i++) {
158 		ret = clk_enable(simple->clks[i]);
159 		if (ret < 0) {
160 			while (--i >= 0)
161 				clk_disable(simple->clks[i]);
162 			return ret;
163 		}
164 	}
165 
166 	return 0;
167 }
168 #endif
169 
170 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
171 	SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
172 			dwc3_of_simple_runtime_resume, NULL)
173 };
174 
175 static const struct of_device_id of_dwc3_simple_match[] = {
176 	{ .compatible = "qcom,dwc3" },
177 	{ .compatible = "rockchip,rk3399-dwc3" },
178 	{ .compatible = "xlnx,zynqmp-dwc3" },
179 	{ .compatible = "cavium,octeon-7130-usb-uctl" },
180 	{ .compatible = "sprd,sc9860-dwc3" },
181 	{ /* Sentinel */ }
182 };
183 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
184 
185 static struct platform_driver dwc3_of_simple_driver = {
186 	.probe		= dwc3_of_simple_probe,
187 	.remove		= dwc3_of_simple_remove,
188 	.driver		= {
189 		.name	= "dwc3-of-simple",
190 		.of_match_table = of_dwc3_simple_match,
191 	},
192 };
193 
194 module_platform_driver(dwc3_of_simple_driver);
195 MODULE_LICENSE("GPL v2");
196 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
197 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
198