1
2
3
4
5
6
7
8
9
10
11
12#include <linux/clk.h>
13#include <linux/clk-provider.h>
14#include <linux/device.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/module.h>
18#include <linux/of_device.h>
19#include <linux/platform_device.h>
20#include <linux/pm.h>
21#include <linux/pm_runtime.h>
22#include <linux/reset.h>
23#include <linux/slab.h>
24
25#define USB20_CLKSET0 0x00
26#define CLKSET0_INTCLK_EN BIT(11)
27#define CLKSET0_PRIVATE BIT(0)
28#define CLKSET0_EXTAL_ONLY (CLKSET0_INTCLK_EN | CLKSET0_PRIVATE)
29
30static const struct clk_bulk_data rcar_usb2_clocks[] = {
31 { .id = "ehci_ohci", },
32 { .id = "hs-usb-if", },
33};
34
35struct usb2_clock_sel_priv {
36 void __iomem *base;
37 struct clk_hw hw;
38 struct clk_bulk_data clks[ARRAY_SIZE(rcar_usb2_clocks)];
39 struct reset_control *rsts;
40 bool extal;
41 bool xtal;
42};
43#define to_priv(_hw) container_of(_hw, struct usb2_clock_sel_priv, hw)
44
45static void usb2_clock_sel_enable_extal_only(struct usb2_clock_sel_priv *priv)
46{
47 u16 val = readw(priv->base + USB20_CLKSET0);
48
49 pr_debug("%s: enter %d %d %x\n", __func__,
50 priv->extal, priv->xtal, val);
51
52 if (priv->extal && !priv->xtal && val != CLKSET0_EXTAL_ONLY)
53 writew(CLKSET0_EXTAL_ONLY, priv->base + USB20_CLKSET0);
54}
55
56static void usb2_clock_sel_disable_extal_only(struct usb2_clock_sel_priv *priv)
57{
58 if (priv->extal && !priv->xtal)
59 writew(CLKSET0_PRIVATE, priv->base + USB20_CLKSET0);
60}
61
62static int usb2_clock_sel_enable(struct clk_hw *hw)
63{
64 struct usb2_clock_sel_priv *priv = to_priv(hw);
65 int ret;
66
67 ret = reset_control_deassert(priv->rsts);
68 if (ret)
69 return ret;
70
71 ret = clk_bulk_prepare_enable(ARRAY_SIZE(priv->clks), priv->clks);
72 if (ret) {
73 reset_control_assert(priv->rsts);
74 return ret;
75 }
76
77 usb2_clock_sel_enable_extal_only(priv);
78
79 return 0;
80}
81
82static void usb2_clock_sel_disable(struct clk_hw *hw)
83{
84 struct usb2_clock_sel_priv *priv = to_priv(hw);
85
86 usb2_clock_sel_disable_extal_only(priv);
87
88 clk_bulk_disable_unprepare(ARRAY_SIZE(priv->clks), priv->clks);
89 reset_control_assert(priv->rsts);
90}
91
92
93
94
95
96
97
98static const struct clk_ops usb2_clock_sel_clock_ops = {
99 .enable = usb2_clock_sel_enable,
100 .disable = usb2_clock_sel_disable,
101};
102
103static const struct of_device_id rcar_usb2_clock_sel_match[] = {
104 { .compatible = "renesas,rcar-gen3-usb2-clock-sel" },
105 { }
106};
107
108static int rcar_usb2_clock_sel_suspend(struct device *dev)
109{
110 struct usb2_clock_sel_priv *priv = dev_get_drvdata(dev);
111
112 usb2_clock_sel_disable_extal_only(priv);
113 pm_runtime_put(dev);
114
115 return 0;
116}
117
118static int rcar_usb2_clock_sel_resume(struct device *dev)
119{
120 struct usb2_clock_sel_priv *priv = dev_get_drvdata(dev);
121
122 pm_runtime_get_sync(dev);
123 usb2_clock_sel_enable_extal_only(priv);
124
125 return 0;
126}
127
128static int rcar_usb2_clock_sel_remove(struct platform_device *pdev)
129{
130 struct device *dev = &pdev->dev;
131 struct usb2_clock_sel_priv *priv = platform_get_drvdata(pdev);
132
133 of_clk_del_provider(dev->of_node);
134 clk_hw_unregister(&priv->hw);
135 pm_runtime_put(dev);
136 pm_runtime_disable(dev);
137
138 return 0;
139}
140
141static int rcar_usb2_clock_sel_probe(struct platform_device *pdev)
142{
143 struct device *dev = &pdev->dev;
144 struct device_node *np = dev->of_node;
145 struct usb2_clock_sel_priv *priv;
146 struct clk *clk;
147 struct clk_init_data init;
148 int ret;
149
150 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
151 if (!priv)
152 return -ENOMEM;
153
154 priv->base = devm_platform_ioremap_resource(pdev, 0);
155 if (IS_ERR(priv->base))
156 return PTR_ERR(priv->base);
157
158 memcpy(priv->clks, rcar_usb2_clocks, sizeof(priv->clks));
159 ret = devm_clk_bulk_get(dev, ARRAY_SIZE(priv->clks), priv->clks);
160 if (ret < 0)
161 return ret;
162
163 priv->rsts = devm_reset_control_array_get(dev, true, false);
164 if (IS_ERR(priv->rsts))
165 return PTR_ERR(priv->rsts);
166
167 pm_runtime_enable(dev);
168 pm_runtime_get_sync(dev);
169
170 clk = devm_clk_get(dev, "usb_extal");
171 if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
172 priv->extal = !!clk_get_rate(clk);
173 clk_disable_unprepare(clk);
174 }
175 clk = devm_clk_get(dev, "usb_xtal");
176 if (!IS_ERR(clk) && !clk_prepare_enable(clk)) {
177 priv->xtal = !!clk_get_rate(clk);
178 clk_disable_unprepare(clk);
179 }
180
181 if (!priv->extal && !priv->xtal) {
182 dev_err(dev, "This driver needs usb_extal or usb_xtal\n");
183 return -ENOENT;
184 }
185
186 platform_set_drvdata(pdev, priv);
187 dev_set_drvdata(dev, priv);
188
189 init.name = "rcar_usb2_clock_sel";
190 init.ops = &usb2_clock_sel_clock_ops;
191 init.flags = 0;
192 init.parent_names = NULL;
193 init.num_parents = 0;
194 priv->hw.init = &init;
195
196 clk = clk_register(NULL, &priv->hw);
197 if (IS_ERR(clk))
198 return PTR_ERR(clk);
199
200 return of_clk_add_hw_provider(np, of_clk_hw_simple_get, &priv->hw);
201}
202
203static const struct dev_pm_ops rcar_usb2_clock_sel_pm_ops = {
204 .suspend = rcar_usb2_clock_sel_suspend,
205 .resume = rcar_usb2_clock_sel_resume,
206};
207
208static struct platform_driver rcar_usb2_clock_sel_driver = {
209 .driver = {
210 .name = "rcar-usb2-clock-sel",
211 .of_match_table = rcar_usb2_clock_sel_match,
212 .pm = &rcar_usb2_clock_sel_pm_ops,
213 },
214 .probe = rcar_usb2_clock_sel_probe,
215 .remove = rcar_usb2_clock_sel_remove,
216};
217builtin_platform_driver(rcar_usb2_clock_sel_driver);
218
219MODULE_DESCRIPTION("Renesas R-Car USB2 clock selector Driver");
220MODULE_LICENSE("GPL v2");
221
