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 	bool			pulse_resets;
31 };
32 
33 static int dwc3_of_simple_clk_init(struct dwc3_of_simple *simple, int count)
34 {
35 	struct device		*dev = simple->dev;
36 	struct device_node	*np = dev->of_node;
37 	int			i;
38 
39 	simple->num_clocks = count;
40 
41 	if (!count)
42 		return 0;
43 
44 	simple->clks = devm_kcalloc(dev, simple->num_clocks,
45 			sizeof(struct clk *), GFP_KERNEL);
46 	if (!simple->clks)
47 		return -ENOMEM;
48 
49 	for (i = 0; i < simple->num_clocks; i++) {
50 		struct clk	*clk;
51 		int		ret;
52 
53 		clk = of_clk_get(np, i);
54 		if (IS_ERR(clk)) {
55 			while (--i >= 0) {
56 				clk_disable_unprepare(simple->clks[i]);
57 				clk_put(simple->clks[i]);
58 			}
59 			return PTR_ERR(clk);
60 		}
61 
62 		ret = clk_prepare_enable(clk);
63 		if (ret < 0) {
64 			while (--i >= 0) {
65 				clk_disable_unprepare(simple->clks[i]);
66 				clk_put(simple->clks[i]);
67 			}
68 			clk_put(clk);
69 
70 			return ret;
71 		}
72 
73 		simple->clks[i] = clk;
74 	}
75 
76 	return 0;
77 }
78 
79 static int dwc3_of_simple_probe(struct platform_device *pdev)
80 {
81 	struct dwc3_of_simple	*simple;
82 	struct device		*dev = &pdev->dev;
83 	struct device_node	*np = dev->of_node;
84 
85 	int			ret;
86 	int			i;
87 	bool			shared_resets = false;
88 
89 	simple = devm_kzalloc(dev, sizeof(*simple), GFP_KERNEL);
90 	if (!simple)
91 		return -ENOMEM;
92 
93 	platform_set_drvdata(pdev, simple);
94 	simple->dev = dev;
95 
96 	if (of_device_is_compatible(np, "amlogic,meson-axg-dwc3") ||
97 	    of_device_is_compatible(np, "amlogic,meson-gxl-dwc3")) {
98 		shared_resets = true;
99 		simple->pulse_resets = true;
100 	}
101 
102 	simple->resets = of_reset_control_array_get(np, shared_resets, true);
103 	if (IS_ERR(simple->resets)) {
104 		ret = PTR_ERR(simple->resets);
105 		dev_err(dev, "failed to get device resets, err=%d\n", ret);
106 		return ret;
107 	}
108 
109 	if (simple->pulse_resets) {
110 		ret = reset_control_reset(simple->resets);
111 		if (ret)
112 			goto err_resetc_put;
113 	} else {
114 		ret = reset_control_deassert(simple->resets);
115 		if (ret)
116 			goto err_resetc_put;
117 	}
118 
119 	ret = dwc3_of_simple_clk_init(simple, of_count_phandle_with_args(np,
120 						"clocks", "#clock-cells"));
121 	if (ret)
122 		goto err_resetc_assert;
123 
124 	ret = of_platform_populate(np, NULL, NULL, dev);
125 	if (ret) {
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 		goto err_resetc_assert;
132 	}
133 
134 	pm_runtime_set_active(dev);
135 	pm_runtime_enable(dev);
136 	pm_runtime_get_sync(dev);
137 
138 	return 0;
139 
140 err_resetc_assert:
141 	if (!simple->pulse_resets)
142 		reset_control_assert(simple->resets);
143 
144 err_resetc_put:
145 	reset_control_put(simple->resets);
146 	return ret;
147 }
148 
149 static int dwc3_of_simple_remove(struct platform_device *pdev)
150 {
151 	struct dwc3_of_simple	*simple = platform_get_drvdata(pdev);
152 	struct device		*dev = &pdev->dev;
153 	int			i;
154 
155 	of_platform_depopulate(dev);
156 
157 	for (i = 0; i < simple->num_clocks; i++) {
158 		clk_disable_unprepare(simple->clks[i]);
159 		clk_put(simple->clks[i]);
160 	}
161 	simple->num_clocks = 0;
162 
163 	if (!simple->pulse_resets)
164 		reset_control_assert(simple->resets);
165 
166 	reset_control_put(simple->resets);
167 
168 	pm_runtime_put_sync(dev);
169 	pm_runtime_disable(dev);
170 
171 	return 0;
172 }
173 
174 #ifdef CONFIG_PM
175 static int dwc3_of_simple_runtime_suspend(struct device *dev)
176 {
177 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
178 	int			i;
179 
180 	for (i = 0; i < simple->num_clocks; i++)
181 		clk_disable(simple->clks[i]);
182 
183 	return 0;
184 }
185 
186 static int dwc3_of_simple_runtime_resume(struct device *dev)
187 {
188 	struct dwc3_of_simple	*simple = dev_get_drvdata(dev);
189 	int			ret;
190 	int			i;
191 
192 	for (i = 0; i < simple->num_clocks; i++) {
193 		ret = clk_enable(simple->clks[i]);
194 		if (ret < 0) {
195 			while (--i >= 0)
196 				clk_disable(simple->clks[i]);
197 			return ret;
198 		}
199 	}
200 
201 	return 0;
202 }
203 #endif
204 
205 static const struct dev_pm_ops dwc3_of_simple_dev_pm_ops = {
206 	SET_RUNTIME_PM_OPS(dwc3_of_simple_runtime_suspend,
207 			dwc3_of_simple_runtime_resume, NULL)
208 };
209 
210 static const struct of_device_id of_dwc3_simple_match[] = {
211 	{ .compatible = "qcom,dwc3" },
212 	{ .compatible = "rockchip,rk3399-dwc3" },
213 	{ .compatible = "xlnx,zynqmp-dwc3" },
214 	{ .compatible = "cavium,octeon-7130-usb-uctl" },
215 	{ .compatible = "sprd,sc9860-dwc3" },
216 	{ .compatible = "amlogic,meson-axg-dwc3" },
217 	{ .compatible = "amlogic,meson-gxl-dwc3" },
218 	{ /* Sentinel */ }
219 };
220 MODULE_DEVICE_TABLE(of, of_dwc3_simple_match);
221 
222 static struct platform_driver dwc3_of_simple_driver = {
223 	.probe		= dwc3_of_simple_probe,
224 	.remove		= dwc3_of_simple_remove,
225 	.driver		= {
226 		.name	= "dwc3-of-simple",
227 		.of_match_table = of_dwc3_simple_match,
228 		.pm	= &dwc3_of_simple_dev_pm_ops,
229 	},
230 };
231 
232 module_platform_driver(dwc3_of_simple_driver);
233 MODULE_LICENSE("GPL v2");
234 MODULE_DESCRIPTION("DesignWare USB3 OF Simple Glue Layer");
235 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
236