1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
4 *
5 * Copyright (C) 2013 Linaro Limited
6 * Matt Porter <mporter@linaro.org>
7 */
8
9#include <linux/clk.h>
10#include <linux/delay.h>
11#include <linux/err.h>
12#include <linux/io.h>
13#include <linux/module.h>
14#include <linux/of.h>
15#include <linux/phy/phy.h>
16#include <linux/platform_device.h>
17
18#define OTGCTL			(0)
19#define OTGCTL_OTGSTAT2		BIT(31)
20#define OTGCTL_OTGSTAT1		BIT(30)
21#define OTGCTL_PRST_N_SW	BIT(11)
22#define OTGCTL_HRESET_N		BIT(10)
23#define OTGCTL_UTMI_LINE_STATE1	BIT(9)
24#define OTGCTL_UTMI_LINE_STATE0	BIT(8)
25
26#define P1CTL			(8)
27#define P1CTL_SOFT_RESET	BIT(1)
28#define P1CTL_NON_DRIVING	BIT(0)
29
30struct bcm_kona_usb {
31	void __iomem *regs;
32};
33
34static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
35{
36	u32 val;
37
38	val = readl(phy->regs + OTGCTL);
39	if (on) {
40		/* Configure and power PHY */
41		val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
42			 OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
43		val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
44	} else {
45		val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
46	}
47	writel(val, phy->regs + OTGCTL);
48}
49
50static int bcm_kona_usb_phy_init(struct phy *gphy)
51{
52	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
53	u32 val;
54
55	/* Soft reset PHY */
56	val = readl(phy->regs + P1CTL);
57	val &= ~P1CTL_NON_DRIVING;
58	val |= P1CTL_SOFT_RESET;
59	writel(val, phy->regs + P1CTL);
60	writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
61	/* Reset needs to be asserted for 2ms */
62	mdelay(2);
63	writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);
64
65	return 0;
66}
67
68static int bcm_kona_usb_phy_power_on(struct phy *gphy)
69{
70	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
71
72	bcm_kona_usb_phy_power(phy, 1);
73
74	return 0;
75}
76
77static int bcm_kona_usb_phy_power_off(struct phy *gphy)
78{
79	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
80
81	bcm_kona_usb_phy_power(phy, 0);
82
83	return 0;
84}
85
86static const struct phy_ops ops = {
87	.init		= bcm_kona_usb_phy_init,
88	.power_on	= bcm_kona_usb_phy_power_on,
89	.power_off	= bcm_kona_usb_phy_power_off,
90	.owner		= THIS_MODULE,
91};
92
93static int bcm_kona_usb2_probe(struct platform_device *pdev)
94{
95	struct device *dev = &pdev->dev;
96	struct bcm_kona_usb *phy;
97	struct phy *gphy;
98	struct phy_provider *phy_provider;
99
100	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
101	if (!phy)
102		return -ENOMEM;
103
104	phy->regs = devm_platform_ioremap_resource(pdev, 0);
105	if (IS_ERR(phy->regs))
106		return PTR_ERR(phy->regs);
107
108	platform_set_drvdata(pdev, phy);
109
110	gphy = devm_phy_create(dev, NULL, &ops);
111	if (IS_ERR(gphy))
112		return PTR_ERR(gphy);
113
114	/* The Kona PHY supports an 8-bit wide UTMI interface */
115	phy_set_bus_width(gphy, 8);
116
117	phy_set_drvdata(gphy, phy);
118
119	phy_provider = devm_of_phy_provider_register(dev,
120			of_phy_simple_xlate);
121
122	return PTR_ERR_OR_ZERO(phy_provider);
123}
124
125static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
126	{ .compatible = "brcm,kona-usb2-phy" },
127	{ /* sentinel */ }
128};
129
130MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);
131
132static struct platform_driver bcm_kona_usb2_driver = {
133	.probe		= bcm_kona_usb2_probe,
134	.driver		= {
135		.name	= "bcm-kona-usb2",
136		.of_match_table = bcm_kona_usb2_dt_ids,
137	},
138};
139
140module_platform_driver(bcm_kona_usb2_driver);
141
142MODULE_ALIAS("platform:bcm-kona-usb2");
143MODULE_AUTHOR("Matt Porter <mporter@linaro.org>");
144MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
145MODULE_LICENSE("GPL v2");
146