aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/phy/phy-bcm-kona-usb2.c
blob: e94f5a6a5645a33acaad36e64da7ac9c2d44b364 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
/*
 * phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
 *
 * Copyright (C) 2013 Linaro Limited
 * Matt Porter <mporter@linaro.org>
 *
 * This software is licensed under the terms of the GNU General Public
 * License version 2, as published by the Free Software Foundation, and
 * may be copied, distributed, and modified under those terms.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>

#define OTGCTL			(0)
#define OTGCTL_OTGSTAT2		BIT(31)
#define OTGCTL_OTGSTAT1		BIT(30)
#define OTGCTL_PRST_N_SW	BIT(11)
#define OTGCTL_HRESET_N		BIT(10)
#define OTGCTL_UTMI_LINE_STATE1	BIT(9)
#define OTGCTL_UTMI_LINE_STATE0	BIT(8)

#define P1CTL			(8)
#define P1CTL_SOFT_RESET	BIT(1)
#define P1CTL_NON_DRIVING	BIT(0)

struct bcm_kona_usb {
	void __iomem *regs;
};

static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
{
	u32 val;

	val = readl(phy->regs + OTGCTL);
	if (on) {
		/* Configure and power PHY */
		val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
			 OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
		val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
	} else {
		val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
	}
	writel(val, phy->regs + OTGCTL);
}

static int bcm_kona_usb_phy_init(struct phy *gphy)
{
	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
	u32 val;

	/* Soft reset PHY */
	val = readl(phy->regs + P1CTL);
	val &= ~P1CTL_NON_DRIVING;
	val |= P1CTL_SOFT_RESET;
	writel(val, phy->regs + P1CTL);
	writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
	/* Reset needs to be asserted for 2ms */
	mdelay(2);
	writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);

	return 0;
}

static int bcm_kona_usb_phy_power_on(struct phy *gphy)
{
	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);

	bcm_kona_usb_phy_power(phy, 1);

	return 0;
}

static int bcm_kona_usb_phy_power_off(struct phy *gphy)
{
	struct bcm_kona_usb *phy = phy_get_drvdata(gphy);

	bcm_kona_usb_phy_power(phy, 0);

	return 0;
}

static struct phy_ops ops = {
	.init		= bcm_kona_usb_phy_init,
	.power_on	= bcm_kona_usb_phy_power_on,
	.power_off	= bcm_kona_usb_phy_power_off,
	.owner		= THIS_MODULE,
};

static int bcm_kona_usb2_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct bcm_kona_usb *phy;
	struct resource *res;
	struct phy *gphy;
	struct phy_provider *phy_provider;

	phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
	if (!phy)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	phy->regs = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(phy->regs))
		return PTR_ERR(phy->regs);

	platform_set_drvdata(pdev, phy);

	gphy = devm_phy_create(dev, &ops, NULL);
	if (IS_ERR(gphy))
		return PTR_ERR(gphy);

	/* The Kona PHY supports an 8-bit wide UTMI interface */
	phy_set_bus_width(gphy, 8);

	phy_set_drvdata(gphy, phy);

	phy_provider = devm_of_phy_provider_register(dev,
			of_phy_simple_xlate);

	return PTR_ERR_OR_ZERO(phy_provider);
}

static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
	{ .compatible = "brcm,kona-usb2-phy" },
	{ /* sentinel */ }
};

MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);

static struct platform_driver bcm_kona_usb2_driver = {
	.probe		= bcm_kona_usb2_probe,
	.driver		= {
		.name	= "bcm-kona-usb2",
		.owner	= THIS_MODULE,
		.of_match_table = bcm_kona_usb2_dt_ids,
	},
};

module_platform_driver(bcm_kona_usb2_driver);

MODULE_ALIAS("platform:bcm-kona-usb2");
MODULE_AUTHOR("Matt Porter <mporter@linaro.org>");
MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
MODULE_LICENSE("GPL v2");