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/clk-provider.h>
29 #include <linux/of.h>
30 #include <linux/of_platform.h>
31 #include <linux/pm_runtime.h>
32 
33 struct dwc3_of_simple {
34 	struct device		*dev;
35 	struct clk		**clks;
36 	int			num_clocks;
37 };
38 
39 static int dwc3_of_simple_probe(struct platform_device *pdev)
40 {
41 	struct dwc3_of_simple	*simple;
42 	struct device		*dev = &pdev->dev;
43 	struct device_node	*np = dev->of_node;
44 
45 	int			ret;
46 	int			i;
47 
48 	simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
49 	if (!simple)
50 		return -ENOMEM;
51 
52 	ret = of_clk_get_parent_count(np);
53 	if (ret < 0)
54 		return ret;
55 
56 	simple->num_clocks = ret;
57 
58 	simple->clks = devm_kcalloc(dev, simple->num_clocks,
59 			sizeof(struct clk *), GFP_KERNEL);
60 	if (!simple->clks)
61 		return -ENOMEM;
62 
63 	simple->dev = dev;
64 
65 	for (i = 0; i < simple->num_clocks; i++) {
66 		struct clk	*clk;
67 
68 		clk = of_clk_get(np, i);
69 		if (IS_ERR(clk)) {
70 			while (--i >= 0)
71 				clk_put(simple->clks[i]);
72 			return PTR_ERR(clk);
73 		}
74 
75 		ret = clk_prepare_enable(clk);
76 		if (ret < 0) {
77 			while (--i >= 0) {
78 				clk_disable_unprepare(simple->clks[i]);
79 				clk_put(simple->clks[i]);
80 			}
81 			clk_put(clk);
82 
83 			return ret;
84 		}
85 
86 		simple->clks[i] = clk;
87 	}
88 
89 	ret = of_platform_populate(np, NULL, NULL, dev);
90 	if (ret) {
91 		for (i = 0; i < simple->num_clocks; i++) {
92 			clk_disable_unprepare(simple->clks[i]);
93 			clk_put(simple->clks[i]);
94 		}
95 
96 		return ret;
97 	}
98 
99 	pm_runtime_set_active(dev);
100 	pm_runtime_enable(dev);
101 	pm_runtime_get_sync(dev);
102 
103 	return 0;
104 }
105 
106 static int dwc3_of_simple_remove(struct platform_device *pdev)
107 {
108 	struct dwc3_of_simple	*simple = platform_get_drvdata(pdev);
109 	struct device		*dev = &pdev->dev;
110 	int			i;
111 
112 	for (i = 0; i < simple->num_clocks; i++) {
113 		clk_unprepare(simple->clks[i]);
114 		clk_put(simple->clks[i]);
115 	}
116 
117 	of_platform_depopulate(dev);
118 
119 	pm_runtime_put_sync(dev);
120 	pm_runtime_disable(dev);
121 
122 	return 0;
123 }
124 
125 #ifdef CONFIG_PM
126 static int dwc3_of_simple_runtime_suspend(struct device *dev)
127 {
128 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
129 	int			i;
130 
131 	for (i = 0; i < simple->num_clocks; i++)
132 		clk_disable(simple->clks[i]);
133 
134 	return 0;
135 }
136 
137 static int dwc3_of_simple_runtime_resume(struct device *dev)
138 {
139 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
140 	int			ret;
141 	int			i;
142 
143 	for (i = 0; i < simple->num_clocks; i++) {
144 		ret = clk_enable(simple->clks[i]);
145 		if (ret < 0) {
146 			while (--i >= 0)
147 				clk_disable(simple->clks[i]);
148 			return ret;
149 		}
150 	}
151 
152 	return 0;
153 }
154 #endif
155 
156 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
157 	SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
158 			dwc3_of_simple_runtime_resume, NULL)
159 };
160 
161 static const struct of_device_id of_dwc3_simple_match[] = {
162 	{ .compatible = "qcom,dwc3" },
163 	{ .compatible = "xlnx,zynqmp-dwc3" },
164 	{ /* Sentinel */ }
165 };
166 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
167 
168 static struct platform_driver dwc3_of_simple_driver = {
169 	.probe		= dwc3_of_simple_probe,
170 	.remove		= dwc3_of_simple_remove,
171 	.driver		= {
172 		.name	= "dwc3-of-simple",
173 		.of_match_table = of_dwc3_simple_match,
174 	},
175 };
176 
177 module_platform_driver(dwc3_of_simple_driver);
178 MODULE_LICENSE("GPL v2");
179 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
180 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
181