summaryrefslogtreecommitdiffstats
path: root/drivers/usb/phy/phy-omap-otg.c
blob: 11598cdb3189c79afd26e2ba1bbe1edcae19afb3 (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
/*
 * OMAP OTG controller driver
 *
 * Based on code from tahvo-usb.c and isp1301_omap.c drivers.
 *
 * Copyright (C) 2005-2006 Nokia Corporation
 * Copyright (C) 2004 Texas Instruments
 * Copyright (C) 2004 David Brownell
 *
 * This file is subject to the terms and conditions of the GNU General
 * Public License. See the file "COPYING" in the main directory of this
 * archive for more details.
 *
 * 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/io.h>
#include <linux/err.h>
#include <linux/extcon.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/platform_data/usb-omap1.h>

struct otg_device {
	void __iomem			*base;
	bool				id;
	bool				vbus;
	struct extcon_specific_cable_nb	vbus_dev;
	struct extcon_specific_cable_nb	id_dev;
	struct notifier_block		vbus_nb;
	struct notifier_block		id_nb;
};

#define OMAP_OTG_CTRL		0x0c
#define OMAP_OTG_ASESSVLD	(1 << 20)
#define OMAP_OTG_BSESSEND	(1 << 19)
#define OMAP_OTG_BSESSVLD	(1 << 18)
#define OMAP_OTG_VBUSVLD	(1 << 17)
#define OMAP_OTG_ID		(1 << 16)
#define OMAP_OTG_XCEIV_OUTPUTS \
	(OMAP_OTG_ASESSVLD | OMAP_OTG_BSESSEND | OMAP_OTG_BSESSVLD | \
	 OMAP_OTG_VBUSVLD  | OMAP_OTG_ID)

static void omap_otg_ctrl(struct otg_device *otg_dev, u32 outputs)
{
	u32 l;

	l = readl(otg_dev->base + OMAP_OTG_CTRL);
	l &= ~OMAP_OTG_XCEIV_OUTPUTS;
	l |= outputs;
	writel(l, otg_dev->base + OMAP_OTG_CTRL);
}

static void omap_otg_set_mode(struct otg_device *otg_dev)
{
	if (!otg_dev->id && otg_dev->vbus)
		/* Set B-session valid. */
		omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSVLD);
	else if (otg_dev->vbus)
		/* Set A-session valid. */
		omap_otg_ctrl(otg_dev, OMAP_OTG_ASESSVLD);
	else if (!otg_dev->id)
		/* Set B-session end to indicate no VBUS. */
		omap_otg_ctrl(otg_dev, OMAP_OTG_ID | OMAP_OTG_BSESSEND);
}

static int omap_otg_id_notifier(struct notifier_block *nb,
				unsigned long event, void *ptr)
{
	struct otg_device *otg_dev = container_of(nb, struct otg_device, id_nb);

	otg_dev->id = event;
	omap_otg_set_mode(otg_dev);

	return NOTIFY_DONE;
}

static int omap_otg_vbus_notifier(struct notifier_block *nb,
				  unsigned long event, void *ptr)
{
	struct otg_device *otg_dev = container_of(nb, struct otg_device,
						  vbus_nb);

	otg_dev->vbus = event;
	omap_otg_set_mode(otg_dev);

	return NOTIFY_DONE;
}

static int omap_otg_probe(struct platform_device *pdev)
{
	const struct omap_usb_config *config = pdev->dev.platform_data;
	struct otg_device *otg_dev;
	struct extcon_dev *extcon;
	int ret;
	u32 rev;

	if (!config || !config->extcon)
		return -ENODEV;

	extcon = extcon_get_extcon_dev(config->extcon);
	if (!extcon)
		return -EPROBE_DEFER;

	otg_dev = devm_kzalloc(&pdev->dev, sizeof(*otg_dev), GFP_KERNEL);
	if (!otg_dev)
		return -ENOMEM;

	otg_dev->base = devm_ioremap_resource(&pdev->dev, &pdev->resource[0]);
	if (IS_ERR(otg_dev->base))
		return PTR_ERR(otg_dev->base);

	otg_dev->id_nb.notifier_call = omap_otg_id_notifier;
	otg_dev->vbus_nb.notifier_call = omap_otg_vbus_notifier;

	ret = extcon_register_interest(&otg_dev->id_dev, config->extcon,
				       "USB-HOST", &otg_dev->id_nb);
	if (ret)
		return ret;

	ret = extcon_register_interest(&otg_dev->vbus_dev, config->extcon,
				       "USB", &otg_dev->vbus_nb);
	if (ret) {
		extcon_unregister_interest(&otg_dev->id_dev);
		return ret;
	}

	otg_dev->id = extcon_get_cable_state(extcon, "USB-HOST");
	otg_dev->vbus = extcon_get_cable_state(extcon, "USB");
	omap_otg_set_mode(otg_dev);

	rev = readl(otg_dev->base);

	dev_info(&pdev->dev,
		 "OMAP USB OTG controller rev %d.%d (%s, id=%d, vbus=%d)\n",
		 (rev >> 4) & 0xf, rev & 0xf, config->extcon, otg_dev->id,
		 otg_dev->vbus);

	return 0;
}

static int omap_otg_remove(struct platform_device *pdev)
{
	struct otg_device *otg_dev = platform_get_drvdata(pdev);

	extcon_unregister_interest(&otg_dev->id_dev);
	extcon_unregister_interest(&otg_dev->vbus_dev);

	return 0;
}

static struct platform_driver omap_otg_driver = {
	.probe		= omap_otg_probe,
	.remove		= omap_otg_remove,
	.driver		= {
		.owner	= THIS_MODULE,
		.name	= "omap_otg",
	},
};
module_platform_driver(omap_otg_driver);

MODULE_DESCRIPTION("OMAP USB OTG controller driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
OpenPOWER on IntegriCloud