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15#include <linux/clk.h>
16#include <linux/clk-provider.h>
17#include <linux/device.h>
18#include <linux/init.h>
19#include <linux/module.h>
20#include <linux/of_device.h>
21#include <linux/platform_device.h>
22#include <linux/pm.h>
23#include <linux/pm_runtime.h>
24#include <linux/slab.h>
25
26#define USB20_CLKSET0 0x00
27#define CLKSET0_INTCLK_EN BIT(11)
28#define CLKSET0_PRIVATE BIT(0)
29#define CLKSET0_EXTAL_ONLY (CLKSET0_INTCLK_EN | CLKSET0_PRIVATE)
30
31struct usb2_clock_sel_priv {
32 void __iomem *base;
33 struct clk_hw hw;
34 bool extal;
35 bool xtal;
36};
37#define to_priv(_hw) container_of(_hw, struct usb2_clock_sel_priv, hw)
38
39static void usb2_clock_sel_enable_extal_only(struct usb2_clock_sel_priv *priv)
40{
41 u16 val = readw(priv->base + USB20_CLKSET0);
42
43 pr_debug("%s: enter %d %d %x\n", __func__,
44 priv->extal, priv->xtal, val);
45
46 if (priv->extal && !priv->xtal && val != CLKSET0_EXTAL_ONLY)
47 writew(CLKSET0_EXTAL_ONLY, priv->base + USB20_CLKSET0);
48}
49
50static void usb2_clock_sel_disable_extal_only(struct usb2_clock_sel_priv *priv)
51{
52 if (priv->extal && !priv->xtal)
53 writew(CLKSET0_PRIVATE, priv->base + USB20_CLKSET0);
54}
55
56static int usb2_clock_sel_enable(struct clk_hw *hw)
57{
58 usb2_clock_sel_enable_extal_only(to_priv(hw));
59
60 return 0;
61}
62
63static void usb2_clock_sel_disable(struct clk_hw *hw)
64{
65 usb2_clock_sel_disable_extal_only(to_priv(hw));
66}
67
68
69
70
71
72
73
74static const struct clk_ops usb2_clock_sel_clock_ops = {
75 .enable = usb2_clock_sel_enable,
76 .disable = usb2_clock_sel_disable,
77};
78
79static const struct of_device_id rcar_usb2_clock_sel_match[] = {
80 { .compatible = "renesas,rcar-gen3-usb2-clock-sel" },
81 { }
82};
83
84static int rcar_usb2_clock_sel_suspend(struct device *dev)
85{
86 struct usb2_clock_sel_priv *priv = dev_get_drvdata(dev);
87
88 usb2_clock_sel_disable_extal_only(priv);
89 pm_runtime_put(dev);
90
91 return 0;
92}
93
94static int rcar_usb2_clock_sel_resume(struct device *dev)
95{
96 struct usb2_clock_sel_priv *priv = dev_get_drvdata(dev);
97
98 pm_runtime_get_sync(dev);
99 usb2_clock_sel_enable_extal_only(priv);
100
101 return 0;
102}
103
104static int rcar_usb2_clock_sel_remove(struct platform_device *pdev)
105{
106 struct device *dev = &pdev->dev;
107 struct usb2_clock_sel_priv *priv = platform_get_drvdata(pdev);
108
109 of_clk_del_provider(dev->of_node);
110 clk_hw_unregister(&priv->hw);
111 pm_runtime_put(dev);
112 pm_runtime_disable(dev);
113
114 return 0;
115}
116
117static int rcar_usb2_clock_sel_probe(struct platform_device *pdev)
118{
119 struct device *dev = &pdev->dev;
120 struct device_node *np = dev->of_node;
121 struct usb2_clock_sel_priv *priv;
122 struct resource *res;
123 struct clk *clk;
124 struct clk_init_data init;
125
126 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
127 if (!priv)
128 return -ENOMEM;
129
130 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
131 priv->base = devm_ioremap_resource(dev, res);
132 if (IS_ERR(priv->base))
133 return PTR_ERR(priv->base);
134
135 pm_runtime_enable(dev);
136 pm_runtime_get_sync(dev);
137
138 clk = devm_clk_get(dev, "usb_extal");
139 if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
140 priv->extal = !!clk_get_rate(clk);
141 clk_disable_unprepare(clk);
142 }
143 clk = devm_clk_get(dev, "usb_xtal");
144 if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
145 priv->xtal = !!clk_get_rate(clk);
146 clk_disable_unprepare(clk);
147 }
148
149 if (!priv->extal && !priv->xtal) {
150 dev_err(dev, "This driver needs usb_extal or usb_xtal\n");
151 return -ENOENT;
152 }
153
154 platform_set_drvdata(pdev, priv);
155 dev_set_drvdata(dev, priv);
156
157 init.name = "rcar_usb2_clock_sel";
158 init.ops = &usb2_clock_sel_clock_ops;
159 init.flags = 0;
160 init.parent_names = NULL;
161 init.num_parents = 0;
162 priv->hw.init = &init;
163
164 clk = clk_register(NULL, &priv->hw);
165 if (IS_ERR(clk))
166 return PTR_ERR(clk);
167
168 return of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
169}
170
171static const struct dev_pm_ops rcar_usb2_clock_sel_pm_ops = {
172 .suspend = rcar_usb2_clock_sel_suspend,
173 .resume = rcar_usb2_clock_sel_resume,
174};
175
176static struct platform_driver rcar_usb2_clock_sel_driver = {
177 .driver = {
178 .name = "rcar-usb2-clock-sel",
179 .of_match_table = rcar_usb2_clock_sel_match,
180 .pm = &rcar_usb2_clock_sel_pm_ops,
181 },
182 .probe = rcar_usb2_clock_sel_probe,
183 .remove = rcar_usb2_clock_sel_remove,
184};
185builtin_platform_driver(rcar_usb2_clock_sel_driver);
186
187MODULE_DESCRIPTION("Renesas R-Car USB2 clock selector Driver");
188MODULE_LICENSE("GPL v2");
189
