1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * PHY driver for NXP LPC18xx/43xx internal USB OTG PHY
4 *
5 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
6 */
7
8#include <linux/clk.h>
9#include <linux/err.h>
10#include <linux/mfd/syscon.h>
11#include <linux/module.h>
12#include <linux/of.h>
13#include <linux/phy/phy.h>
14#include <linux/platform_device.h>
15#include <linux/regmap.h>
16
17/* USB OTG PHY register offset and bit in CREG */
18#define LPC18XX_CREG_CREG0 0x004
19#define LPC18XX_CREG_CREG0_USB0PHY BIT(5)
20
21struct lpc18xx_usb_otg_phy {
22 struct phy *phy;
23 struct clk *clk;
24 struct regmap *reg;
25};
26
27static int lpc18xx_usb_otg_phy_init(struct phy *phy)
28{
29 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
30 int ret;
31
32 /* The PHY must be clocked at 480 MHz */
33 ret = clk_set_rate(clk: lpc->clk, rate: 480000000);
34 if (ret)
35 return ret;
36
37 return clk_prepare(clk: lpc->clk);
38}
39
40static int lpc18xx_usb_otg_phy_exit(struct phy *phy)
41{
42 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
43
44 clk_unprepare(clk: lpc->clk);
45
46 return 0;
47}
48
49static int lpc18xx_usb_otg_phy_power_on(struct phy *phy)
50{
51 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
52 int ret;
53
54 ret = clk_enable(clk: lpc->clk);
55 if (ret)
56 return ret;
57
58 /* The bit in CREG is cleared to enable the PHY */
59 ret = regmap_update_bits(map: lpc->reg, LPC18XX_CREG_CREG0,
60 LPC18XX_CREG_CREG0_USB0PHY, val: 0);
61 if (ret) {
62 clk_disable(clk: lpc->clk);
63 return ret;
64 }
65
66 return 0;
67}
68
69static int lpc18xx_usb_otg_phy_power_off(struct phy *phy)
70{
71 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
72 int ret;
73
74 ret = regmap_update_bits(map: lpc->reg, LPC18XX_CREG_CREG0,
75 LPC18XX_CREG_CREG0_USB0PHY,
76 LPC18XX_CREG_CREG0_USB0PHY);
77 if (ret)
78 return ret;
79
80 clk_disable(clk: lpc->clk);
81
82 return 0;
83}
84
85static const struct phy_ops lpc18xx_usb_otg_phy_ops = {
86 .init = lpc18xx_usb_otg_phy_init,
87 .exit = lpc18xx_usb_otg_phy_exit,
88 .power_on = lpc18xx_usb_otg_phy_power_on,
89 .power_off = lpc18xx_usb_otg_phy_power_off,
90 .owner = THIS_MODULE,
91};
92
93static int lpc18xx_usb_otg_phy_probe(struct platform_device *pdev)
94{
95 struct phy_provider *phy_provider;
96 struct lpc18xx_usb_otg_phy *lpc;
97
98 lpc = devm_kzalloc(dev: &pdev->dev, size: sizeof(*lpc), GFP_KERNEL);
99 if (!lpc)
100 return -ENOMEM;
101
102 lpc->reg = syscon_node_to_regmap(np: pdev->dev.of_node->parent);
103 if (IS_ERR(ptr: lpc->reg)) {
104 dev_err(&pdev->dev, "failed to get syscon\n");
105 return PTR_ERR(ptr: lpc->reg);
106 }
107
108 lpc->clk = devm_clk_get(dev: &pdev->dev, NULL);
109 if (IS_ERR(ptr: lpc->clk)) {
110 dev_err(&pdev->dev, "failed to get clock\n");
111 return PTR_ERR(ptr: lpc->clk);
112 }
113
114 lpc->phy = devm_phy_create(dev: &pdev->dev, NULL, ops: &lpc18xx_usb_otg_phy_ops);
115 if (IS_ERR(ptr: lpc->phy)) {
116 dev_err(&pdev->dev, "failed to create PHY\n");
117 return PTR_ERR(ptr: lpc->phy);
118 }
119
120 phy_set_drvdata(phy: lpc->phy, data: lpc);
121
122 phy_provider = devm_of_phy_provider_register(&pdev->dev,
123 of_phy_simple_xlate);
124
125 return PTR_ERR_OR_ZERO(ptr: phy_provider);
126}
127
128static const struct of_device_id lpc18xx_usb_otg_phy_match[] = {
129 { .compatible = "nxp,lpc1850-usb-otg-phy" },
130 { }
131};
132MODULE_DEVICE_TABLE(of, lpc18xx_usb_otg_phy_match);
133
134static struct platform_driver lpc18xx_usb_otg_phy_driver = {
135 .probe = lpc18xx_usb_otg_phy_probe,
136 .driver = {
137 .name = "lpc18xx-usb-otg-phy",
138 .of_match_table = lpc18xx_usb_otg_phy_match,
139 },
140};
141module_platform_driver(lpc18xx_usb_otg_phy_driver);
142
143MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
144MODULE_DESCRIPTION("NXP LPC18xx/43xx USB OTG PHY driver");
145MODULE_LICENSE("GPL v2");
146

source code of linux/drivers/phy/phy-lpc18xx-usb-otg.c