xref: /openbmc/linux/drivers/phy/starfive/phy-jh7110-usb.c (revision 4d75f5c664195b970e1cd2fd25b65b5eff257a0a)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * StarFive JH7110 USB 2.0 PHY driver
4  *
5  * Copyright (C) 2023 StarFive Technology Co., Ltd.
6  * Author: Minda Chen <minda.chen@starfivetech.com>
7  */
8 
9 #include <linux/bits.h>
10 #include <linux/clk.h>
11 #include <linux/err.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/phy/phy.h>
15 #include <linux/platform_device.h>
16 #include <linux/usb/of.h>
17 
18 #define USB_125M_CLK_RATE		125000000
19 #define USB_CLK_MODE_OFF		0x0
20 #define USB_CLK_MODE_RX_NORMAL_PWR	BIT(1)
21 #define USB_LS_KEEPALIVE_OFF		0x4
22 #define USB_LS_KEEPALIVE_ENABLE		BIT(4)
23 
24 struct jh7110_usb2_phy {
25 	struct phy *phy;
26 	void __iomem *regs;
27 	struct clk *usb_125m_clk;
28 	struct clk *app_125m;
29 	enum phy_mode mode;
30 };
31 
usb2_set_ls_keepalive(struct jh7110_usb2_phy * phy,bool set)32 static void usb2_set_ls_keepalive(struct jh7110_usb2_phy *phy, bool set)
33 {
34 	unsigned int val;
35 
36 	/* Host mode enable the LS speed keep-alive signal */
37 	val = readl(phy->regs + USB_LS_KEEPALIVE_OFF);
38 	if (set)
39 		val |= USB_LS_KEEPALIVE_ENABLE;
40 	else
41 		val &= ~USB_LS_KEEPALIVE_ENABLE;
42 
43 	writel(val, phy->regs + USB_LS_KEEPALIVE_OFF);
44 }
45 
usb2_phy_set_mode(struct phy * _phy,enum phy_mode mode,int submode)46 static int usb2_phy_set_mode(struct phy *_phy,
47 			     enum phy_mode mode, int submode)
48 {
49 	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
50 
51 	switch (mode) {
52 	case PHY_MODE_USB_HOST:
53 	case PHY_MODE_USB_DEVICE:
54 	case PHY_MODE_USB_OTG:
55 		break;
56 	default:
57 		return -EINVAL;
58 	}
59 
60 	if (mode != phy->mode) {
61 		dev_dbg(&_phy->dev, "Changing phy to %d\n", mode);
62 		phy->mode = mode;
63 		usb2_set_ls_keepalive(phy, (mode != PHY_MODE_USB_DEVICE));
64 	}
65 
66 	return 0;
67 }
68 
jh7110_usb2_phy_init(struct phy * _phy)69 static int jh7110_usb2_phy_init(struct phy *_phy)
70 {
71 	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
72 	int ret;
73 	unsigned int val;
74 
75 	ret = clk_set_rate(phy->usb_125m_clk, USB_125M_CLK_RATE);
76 	if (ret)
77 		return ret;
78 
79 	ret = clk_prepare_enable(phy->app_125m);
80 	if (ret)
81 		return ret;
82 
83 	val = readl(phy->regs + USB_CLK_MODE_OFF);
84 	val |= USB_CLK_MODE_RX_NORMAL_PWR;
85 	writel(val, phy->regs + USB_CLK_MODE_OFF);
86 
87 	return 0;
88 }
89 
jh7110_usb2_phy_exit(struct phy * _phy)90 static int jh7110_usb2_phy_exit(struct phy *_phy)
91 {
92 	struct jh7110_usb2_phy *phy = phy_get_drvdata(_phy);
93 
94 	clk_disable_unprepare(phy->app_125m);
95 
96 	return 0;
97 }
98 
99 static const struct phy_ops jh7110_usb2_phy_ops = {
100 	.init		= jh7110_usb2_phy_init,
101 	.exit		= jh7110_usb2_phy_exit,
102 	.set_mode	= usb2_phy_set_mode,
103 	.owner		= THIS_MODULE,
104 };
105 
jh7110_usb_phy_probe(struct platform_device * pdev)106 static int jh7110_usb_phy_probe(struct platform_device *pdev)
107 {
108 	struct jh7110_usb2_phy *phy;
109 	struct device *dev = &pdev->dev;
110 	struct phy_provider *phy_provider;
111 
112 	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
113 	if (!phy)
114 		return -ENOMEM;
115 
116 	phy->usb_125m_clk = devm_clk_get(dev, "125m");
117 	if (IS_ERR(phy->usb_125m_clk))
118 		return dev_err_probe(dev, PTR_ERR(phy->usb_125m_clk),
119 			"Failed to get 125m clock\n");
120 
121 	phy->app_125m = devm_clk_get(dev, "app_125m");
122 	if (IS_ERR(phy->app_125m))
123 		return dev_err_probe(dev, PTR_ERR(phy->app_125m),
124 			"Failed to get app 125m clock\n");
125 
126 	phy->regs = devm_platform_ioremap_resource(pdev, 0);
127 	if (IS_ERR(phy->regs))
128 		return dev_err_probe(dev, PTR_ERR(phy->regs),
129 			"Failed to map phy base\n");
130 
131 	phy->phy = devm_phy_create(dev, NULL, &jh7110_usb2_phy_ops);
132 	if (IS_ERR(phy->phy))
133 		return dev_err_probe(dev, PTR_ERR(phy->phy),
134 			"Failed to create phy\n");
135 
136 	phy_set_drvdata(phy->phy, phy);
137 	phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
138 
139 	return PTR_ERR_OR_ZERO(phy_provider);
140 }
141 
142 static const struct of_device_id jh7110_usb_phy_of_match[] = {
143 	{ .compatible = "starfive,jh7110-usb-phy" },
144 	{ /* sentinel */ },
145 };
146 MODULE_DEVICE_TABLE(of, jh7110_usb_phy_of_match);
147 
148 static struct platform_driver jh7110_usb_phy_driver = {
149 	.probe	= jh7110_usb_phy_probe,
150 	.driver = {
151 		.of_match_table	= jh7110_usb_phy_of_match,
152 		.name  = "jh7110-usb-phy",
153 	}
154 };
155 module_platform_driver(jh7110_usb_phy_driver);
156 
157 MODULE_DESCRIPTION("StarFive JH7110 USB 2.0 PHY driver");
158 MODULE_AUTHOR("Minda Chen <minda.chen@starfivetech.com>");
159 MODULE_LICENSE("GPL");
160