blob: 3b7a71eb5b7e03bc8ba0de65867dd788be957876 [file] [log] [blame]
Joachim Eastwoodcbf919b2015-07-09 22:48:25 +02001/*
2 * PHY driver for NXP LPC18xx/43xx internal USB OTG PHY
3 *
4 * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 */
11
12#include <linux/clk.h>
13#include <linux/err.h>
14#include <linux/mfd/syscon.h>
15#include <linux/module.h>
16#include <linux/of.h>
17#include <linux/phy/phy.h>
18#include <linux/platform_device.h>
19#include <linux/regmap.h>
20
21/* USB OTG PHY register offset and bit in CREG */
22#define LPC18XX_CREG_CREG0 0x004
23#define LPC18XX_CREG_CREG0_USB0PHY BIT(5)
24
25struct lpc18xx_usb_otg_phy {
26 struct phy *phy;
27 struct clk *clk;
28 struct regmap *reg;
29};
30
31static int lpc18xx_usb_otg_phy_init(struct phy *phy)
32{
33 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
34 int ret;
35
Joachim Eastwoodcfd093b2015-08-09 00:02:41 +020036 /* The PHY must be clocked at 480 MHz */
37 ret = clk_set_rate(lpc->clk, 480000000);
Joachim Eastwoodcbf919b2015-07-09 22:48:25 +020038 if (ret)
39 return ret;
40
Joachim Eastwoodcfd093b2015-08-09 00:02:41 +020041 return clk_prepare(lpc->clk);
Joachim Eastwoodcbf919b2015-07-09 22:48:25 +020042}
43
44static int lpc18xx_usb_otg_phy_exit(struct phy *phy)
45{
46 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
47
48 clk_unprepare(lpc->clk);
49
50 return 0;
51}
52
53static int lpc18xx_usb_otg_phy_power_on(struct phy *phy)
54{
55 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
56 int ret;
57
58 ret = clk_enable(lpc->clk);
59 if (ret)
60 return ret;
61
62 /* The bit in CREG is cleared to enable the PHY */
63 return regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0,
64 LPC18XX_CREG_CREG0_USB0PHY, 0);
65}
66
67static int lpc18xx_usb_otg_phy_power_off(struct phy *phy)
68{
69 struct lpc18xx_usb_otg_phy *lpc = phy_get_drvdata(phy);
70 int ret;
71
72 ret = regmap_update_bits(lpc->reg, LPC18XX_CREG_CREG0,
73 LPC18XX_CREG_CREG0_USB0PHY,
74 LPC18XX_CREG_CREG0_USB0PHY);
75 if (ret)
76 return ret;
77
78 clk_disable(lpc->clk);
79
80 return 0;
81}
82
83static const struct phy_ops lpc18xx_usb_otg_phy_ops = {
84 .init = lpc18xx_usb_otg_phy_init,
85 .exit = lpc18xx_usb_otg_phy_exit,
86 .power_on = lpc18xx_usb_otg_phy_power_on,
87 .power_off = lpc18xx_usb_otg_phy_power_off,
88 .owner = THIS_MODULE,
89};
90
91static int lpc18xx_usb_otg_phy_probe(struct platform_device *pdev)
92{
93 struct phy_provider *phy_provider;
94 struct lpc18xx_usb_otg_phy *lpc;
95
96 lpc = devm_kzalloc(&pdev->dev, sizeof(*lpc), GFP_KERNEL);
97 if (!lpc)
98 return -ENOMEM;
99
100 lpc->reg = syscon_node_to_regmap(pdev->dev.of_node->parent);
101 if (IS_ERR(lpc->reg)) {
102 dev_err(&pdev->dev, "failed to get syscon\n");
103 return PTR_ERR(lpc->reg);
104 }
105
106 lpc->clk = devm_clk_get(&pdev->dev, NULL);
107 if (IS_ERR(lpc->clk)) {
108 dev_err(&pdev->dev, "failed to get clock\n");
109 return PTR_ERR(lpc->clk);
110 }
111
112 lpc->phy = devm_phy_create(&pdev->dev, NULL, &lpc18xx_usb_otg_phy_ops);
113 if (IS_ERR(lpc->phy)) {
114 dev_err(&pdev->dev, "failed to create PHY\n");
115 return PTR_ERR(lpc->phy);
116 }
117
118 phy_set_drvdata(lpc->phy, lpc);
119
120 phy_provider = devm_of_phy_provider_register(&pdev->dev,
121 of_phy_simple_xlate);
122
123 return PTR_ERR_OR_ZERO(phy_provider);
124}
125
126static const struct of_device_id lpc18xx_usb_otg_phy_match[] = {
127 { .compatible = "nxp,lpc1850-usb-otg-phy" },
128 { }
129};
130MODULE_DEVICE_TABLE(of, lpc18xx_usb_otg_phy_match);
131
132static struct platform_driver lpc18xx_usb_otg_phy_driver = {
133 .probe = lpc18xx_usb_otg_phy_probe,
134 .driver = {
135 .name = "lpc18xx-usb-otg-phy",
136 .of_match_table = lpc18xx_usb_otg_phy_match,
137 },
138};
139module_platform_driver(lpc18xx_usb_otg_phy_driver);
140
141MODULE_AUTHOR("Joachim Eastwood <manabian@gmail.com>");
142MODULE_DESCRIPTION("NXP LPC18xx/43xx USB OTG PHY driver");
143MODULE_LICENSE("GPL v2");