summaryrefslogtreecommitdiff
path: root/drivers/usb/phy/rcar-phy.c
blob: a35681b0c5014fdbaa44cbbf97facb2f2ec74117 (plain)
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
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
/*
 * Renesas R-Car USB phy driver
 *
 * Copyright (C) 2012 Renesas Solutions Corp.
 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/usb/otg.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/module.h>

/* USBH common register */
#define USBPCTRL0	0x0800
#define USBPCTRL1	0x0804
#define USBST		0x0808
#define USBEH0		0x080C
#define USBOH0		0x081C
#define USBCTL0		0x0858
#define EIIBC1		0x0094
#define EIIBC2		0x009C

/* USBPCTRL1 */
#define PHY_RST		(1 << 2)
#define PLL_ENB		(1 << 1)
#define PHY_ENB		(1 << 0)

/* USBST */
#define ST_ACT		(1 << 31)
#define ST_PLL		(1 << 30)

struct rcar_usb_phy_priv {
	struct usb_phy phy;
	spinlock_t lock;

	void __iomem *reg0;
	void __iomem *reg1;
	int counter;
};

#define usb_phy_to_priv(p) container_of(p, struct rcar_usb_phy_priv, phy)


/*
 * USB initial/install operation.
 *
 * This function setup USB phy.
 * The used value and setting order came from
 * [USB :: Initial setting] on datasheet.
 */
static int rcar_usb_phy_init(struct usb_phy *phy)
{
	struct rcar_usb_phy_priv *priv = usb_phy_to_priv(phy);
	struct device *dev = phy->dev;
	void __iomem *reg0 = priv->reg0;
	void __iomem *reg1 = priv->reg1;
	int i;
	u32 val;
	unsigned long flags;

	spin_lock_irqsave(&priv->lock, flags);
	if (priv->counter++ == 0) {

		/*
		 * USB phy start-up
		 */

		/* (1) USB-PHY standby release */
		iowrite32(PHY_ENB, (reg0 + USBPCTRL1));

		/* (2) start USB-PHY internal PLL */
		iowrite32(PHY_ENB | PLL_ENB, (reg0 + USBPCTRL1));

		/* (3) USB module status check */
		for (i = 0; i < 1024; i++) {
			udelay(10);
			val = ioread32(reg0 + USBST);
			if (val == (ST_ACT | ST_PLL))
				break;
		}

		if (val != (ST_ACT | ST_PLL)) {
			dev_err(dev, "USB phy not ready\n");
			goto phy_init_end;
		}

		/* (4) USB-PHY reset clear */
		iowrite32(PHY_ENB | PLL_ENB | PHY_RST, (reg0 + USBPCTRL1));

		/* set platform specific port settings */
		iowrite32(0x00000000, (reg0 + USBPCTRL0));

		/*
		 * EHCI IP internal buffer setting
		 * EHCI IP internal buffer enable
		 *
		 * These are recommended value of a datasheet
		 * see [USB :: EHCI internal buffer setting]
		 */
		iowrite32(0x00ff0040, (reg0 + EIIBC1));
		iowrite32(0x00ff0040, (reg1 + EIIBC1));

		iowrite32(0x00000001, (reg0 + EIIBC2));
		iowrite32(0x00000001, (reg1 + EIIBC2));

		/*
		 * Bus alignment settings
		 */

		/* (1) EHCI bus alignment (little endian) */
		iowrite32(0x00000000, (reg0 + USBEH0));

		/* (1) OHCI bus alignment (little endian) */
		iowrite32(0x00000000, (reg0 + USBOH0));
	}

phy_init_end:
	spin_unlock_irqrestore(&priv->lock, flags);

	return 0;
}

static void rcar_usb_phy_shutdown(struct usb_phy *phy)
{
	struct rcar_usb_phy_priv *priv = usb_phy_to_priv(phy);
	void __iomem *reg0 = priv->reg0;
	unsigned long flags;

	spin_lock_irqsave(&priv->lock, flags);

	if (priv->counter-- == 1) { /* last user */
		iowrite32(0x00000000, (reg0 + USBPCTRL0));
		iowrite32(0x00000000, (reg0 + USBPCTRL1));
	}

	spin_unlock_irqrestore(&priv->lock, flags);
}

static int rcar_usb_phy_probe(struct platform_device *pdev)
{
	struct rcar_usb_phy_priv *priv;
	struct resource *res0, *res1;
	struct device *dev = &pdev->dev;
	void __iomem *reg0, *reg1;
	int ret;

	res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	res1 = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	if (!res0 || !res1) {
		dev_err(dev, "Not enough platform resources\n");
		return -EINVAL;
	}

	/*
	 * CAUTION
	 *
	 * Because this phy address is also mapped under OHCI/EHCI address area,
	 * this driver can't use devm_request_and_ioremap(dev, res) here
	 */
	reg0 = devm_ioremap_nocache(dev, res0->start, resource_size(res0));
	reg1 = devm_ioremap_nocache(dev, res1->start, resource_size(res1));
	if (!reg0 || !reg1) {
		dev_err(dev, "ioremap error\n");
		return -ENOMEM;
	}

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv) {
		dev_err(dev, "priv data allocation error\n");
		return -ENOMEM;
	}

	priv->reg0		= reg0;
	priv->reg1		= reg1;
	priv->counter		= 0;
	priv->phy.dev		= dev;
	priv->phy.label		= dev_name(dev);
	priv->phy.init		= rcar_usb_phy_init;
	priv->phy.shutdown	= rcar_usb_phy_shutdown;
	spin_lock_init(&priv->lock);

	ret = usb_add_phy(&priv->phy, USB_PHY_TYPE_USB2);
	if (ret < 0) {
		dev_err(dev, "usb phy addition error\n");
		return ret;
	}

	platform_set_drvdata(pdev, priv);

	return ret;
}

static int rcar_usb_phy_remove(struct platform_device *pdev)
{
	struct rcar_usb_phy_priv *priv = platform_get_drvdata(pdev);

	usb_remove_phy(&priv->phy);

	return 0;
}

static struct platform_driver rcar_usb_phy_driver = {
	.driver		= {
		.name	= "rcar_usb_phy",
	},
	.probe		= rcar_usb_phy_probe,
	.remove		= rcar_usb_phy_remove,
};

module_platform_driver(rcar_usb_phy_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Renesas R-Car USB phy");
MODULE_AUTHOR("Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>");