aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/phy/phy-rcar-gen2-usb.c
blob: db3ab34cddb4cbc6be6df4e66596b11186235477 (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
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
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
/*
 * Renesas R-Car Gen2 USB phy driver
 *
 * Copyright (C) 2013 Renesas Solutions Corp.
 * Copyright (C) 2013 Cogent Embedded, Inc.
 *
 * 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/clk.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_data/usb-rcar-gen2-phy.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/usb/otg.h>

struct rcar_gen2_usb_phy_priv {
	struct usb_phy phy;
	void __iomem *base;
	struct clk *clk;
	spinlock_t lock;
	int usecount;
	u32 ugctrl2;
};

#define usb_phy_to_priv(p) container_of(p, struct rcar_gen2_usb_phy_priv, phy)

/* Low Power Status register */
#define USBHS_LPSTS_REG			0x02
#define USBHS_LPSTS_SUSPM		(1 << 14)

/* USB General control register */
#define USBHS_UGCTRL_REG		0x80
#define USBHS_UGCTRL_CONNECT		(1 << 2)
#define USBHS_UGCTRL_PLLRESET		(1 << 0)

/* USB General control register 2 */
#define USBHS_UGCTRL2_REG		0x84
#define USBHS_UGCTRL2_USB0_PCI		(1 << 4)
#define USBHS_UGCTRL2_USB0_HS		(3 << 4)
#define USBHS_UGCTRL2_USB2_PCI		(0 << 31)
#define USBHS_UGCTRL2_USB2_SS		(1 << 31)

/* USB General status register */
#define USBHS_UGSTS_REG			0x88
#define USBHS_UGSTS_LOCK		(3 << 8)

/* Enable USBHS internal phy */
static int __rcar_gen2_usbhs_phy_enable(void __iomem *base)
{
	u32 val;
	int i;

	/* USBHS PHY power on */
	val = ioread32(base + USBHS_UGCTRL_REG);
	val &= ~USBHS_UGCTRL_PLLRESET;
	iowrite32(val, base + USBHS_UGCTRL_REG);

	val = ioread16(base + USBHS_LPSTS_REG);
	val |= USBHS_LPSTS_SUSPM;
	iowrite16(val, base + USBHS_LPSTS_REG);

	for (i = 0; i < 20; i++) {
		val = ioread32(base + USBHS_UGSTS_REG);
		if ((val & USBHS_UGSTS_LOCK) == USBHS_UGSTS_LOCK) {
			val = ioread32(base + USBHS_UGCTRL_REG);
			val |= USBHS_UGCTRL_CONNECT;
			iowrite32(val, base + USBHS_UGCTRL_REG);
			return 0;
		}
		udelay(1);
	}

	/* Timed out waiting for the PLL lock */
	return -ETIMEDOUT;
}

/* Disable USBHS internal phy */
static int __rcar_gen2_usbhs_phy_disable(void __iomem *base)
{
	u32 val;

	/* USBHS PHY power off */
	val = ioread32(base + USBHS_UGCTRL_REG);
	val &= ~USBHS_UGCTRL_CONNECT;
	iowrite32(val, base + USBHS_UGCTRL_REG);

	val = ioread16(base + USBHS_LPSTS_REG);
	val &= ~USBHS_LPSTS_SUSPM;
	iowrite16(val, base + USBHS_LPSTS_REG);

	val = ioread32(base + USBHS_UGCTRL_REG);
	val |= USBHS_UGCTRL_PLLRESET;
	iowrite32(val, base + USBHS_UGCTRL_REG);
	return 0;
}

/* Setup USB channels */
static void __rcar_gen2_usb_phy_init(struct rcar_gen2_usb_phy_priv *priv)
{
	u32 val;

	clk_prepare_enable(priv->clk);

	/* Set USB channels in the USBHS UGCTRL2 register */
	val = ioread32(priv->base + USBHS_UGCTRL2_REG);
	val &= ~(USBHS_UGCTRL2_USB0_HS | USBHS_UGCTRL2_USB2_SS);
	val |= priv->ugctrl2;
	iowrite32(val, priv->base + USBHS_UGCTRL2_REG);
}

/* Shutdown USB channels */
static void __rcar_gen2_usb_phy_shutdown(struct rcar_gen2_usb_phy_priv *priv)
{
	__rcar_gen2_usbhs_phy_disable(priv->base);
	clk_disable_unprepare(priv->clk);
}

static int rcar_gen2_usb_phy_set_suspend(struct usb_phy *phy, int suspend)
{
	struct rcar_gen2_usb_phy_priv *priv = usb_phy_to_priv(phy);
	unsigned long flags;
	int retval;

	spin_lock_irqsave(&priv->lock, flags);
	retval = suspend ? __rcar_gen2_usbhs_phy_disable(priv->base) :
			   __rcar_gen2_usbhs_phy_enable(priv->base);
	spin_unlock_irqrestore(&priv->lock, flags);
	return retval;
}

static int rcar_gen2_usb_phy_init(struct usb_phy *phy)
{
	struct rcar_gen2_usb_phy_priv *priv = usb_phy_to_priv(phy);
	unsigned long flags;

	spin_lock_irqsave(&priv->lock, flags);
	/*
	 * Enable the clock and setup USB channels
	 * if it's the first user
	 */
	if (!priv->usecount++)
		__rcar_gen2_usb_phy_init(priv);
	spin_unlock_irqrestore(&priv->lock, flags);
	return 0;
}

static void rcar_gen2_usb_phy_shutdown(struct usb_phy *phy)
{
	struct rcar_gen2_usb_phy_priv *priv = usb_phy_to_priv(phy);
	unsigned long flags;

	spin_lock_irqsave(&priv->lock, flags);
	if (!priv->usecount) {
		dev_warn(phy->dev, "Trying to disable phy with 0 usecount\n");
		goto out;
	}

	/* Disable everything if it's the last user */
	if (!--priv->usecount)
		__rcar_gen2_usb_phy_shutdown(priv);
out:
	spin_unlock_irqrestore(&priv->lock, flags);
}

static int rcar_gen2_usb_phy_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct rcar_gen2_phy_platform_data *pdata;
	struct rcar_gen2_usb_phy_priv *priv;
	struct resource *res;
	void __iomem *base;
	struct clk *clk;
	int retval;

	pdata = dev_get_platdata(&pdev->dev);
	if (!pdata) {
		dev_err(dev, "No platform data\n");
		return -EINVAL;
	}

	clk = devm_clk_get(&pdev->dev, "usbhs");
	if (IS_ERR(clk)) {
		dev_err(&pdev->dev, "Can't get the clock\n");
		return PTR_ERR(clk);
	}

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	base = devm_ioremap_resource(dev, res);
	if (IS_ERR(base))
		return PTR_ERR(base);

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

	spin_lock_init(&priv->lock);
	priv->clk = clk;
	priv->base = base;
	priv->ugctrl2 = pdata->chan0_pci ?
			USBHS_UGCTRL2_USB0_PCI : USBHS_UGCTRL2_USB0_HS;
	priv->ugctrl2 |= pdata->chan2_pci ?
			USBHS_UGCTRL2_USB2_PCI : USBHS_UGCTRL2_USB2_SS;
	priv->phy.dev = dev;
	priv->phy.label = dev_name(dev);
	priv->phy.init = rcar_gen2_usb_phy_init;
	priv->phy.shutdown = rcar_gen2_usb_phy_shutdown;
	priv->phy.set_suspend = rcar_gen2_usb_phy_set_suspend;

	retval = usb_add_phy(&priv->phy, USB_PHY_TYPE_USB2);
	if (retval < 0) {
		dev_err(dev, "Failed to add USB phy\n");
		return retval;
	}

	platform_set_drvdata(pdev, priv);

	return retval;
}

static int rcar_gen2_usb_phy_remove(struct platform_device *pdev)
{
	struct rcar_gen2_usb_phy_priv *priv = platform_get_drvdata(pdev);

	usb_remove_phy(&priv->phy);

	return 0;
}

static struct platform_driver rcar_gen2_usb_phy_driver = {
	.driver = {
		.name = "usb_phy_rcar_gen2",
	},
	.probe = rcar_gen2_usb_phy_probe,
	.remove = rcar_gen2_usb_phy_remove,
};

module_platform_driver(rcar_gen2_usb_phy_driver);

MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("Renesas R-Car Gen2 USB phy");
MODULE_AUTHOR("Valentine Barshak <valentine.barshak@cogentembedded.com>");