aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/otg/nop-usb-xceiv.c
blob: 58b26df6afd1b3a457f2f1897b3c43d176a6e42c (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
/*
 * drivers/usb/otg/nop-usb-xceiv.c
 *
 * NOP USB transceiver for all USB transceiver which are either built-in
 * into USB IP or which are mostly autonomous.
 *
 * Copyright (C) 2009 Texas Instruments Inc
 * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Current status:
 *	This provides a "nop" transceiver for PHYs which are
 *	autonomous such as isp1504, isp1707, etc.
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/usb/otg.h>
#include <linux/slab.h>

struct nop_usb_xceiv {
	struct usb_phy		phy;
	struct device		*dev;
};

static struct platform_device *pd;

void usb_nop_xceiv_register(void)
{
	if (pd)
		return;
	pd = platform_device_register_simple("nop_usb_xceiv", -1, NULL, 0);
	if (!pd) {
		printk(KERN_ERR "Unable to register usb nop transceiver\n");
		return;
	}
}
EXPORT_SYMBOL(usb_nop_xceiv_register);

void usb_nop_xceiv_unregister(void)
{
	platform_device_unregister(pd);
	pd = NULL;
}
EXPORT_SYMBOL(usb_nop_xceiv_unregister);

static int nop_set_suspend(struct usb_phy *x, int suspend)
{
	return 0;
}

static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
{
	if (!otg)
		return -ENODEV;

	if (!gadget) {
		otg->gadget = NULL;
		return -ENODEV;
	}

	otg->gadget = gadget;
	otg->phy->state = OTG_STATE_B_IDLE;
	return 0;
}

static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
{
	if (!otg)
		return -ENODEV;

	if (!host) {
		otg->host = NULL;
		return -ENODEV;
	}

	otg->host = host;
	return 0;
}

static int __devinit nop_usb_xceiv_probe(struct platform_device *pdev)
{
	struct nop_usb_xceiv	*nop;
	int err;

	nop = kzalloc(sizeof *nop, GFP_KERNEL);
	if (!nop)
		return -ENOMEM;

	nop->phy.otg = kzalloc(sizeof *nop->phy.otg, GFP_KERNEL);
	if (!nop->phy.otg) {
		kfree(nop);
		return -ENOMEM;
	}

	nop->dev		= &pdev->dev;
	nop->phy.dev		= nop->dev;
	nop->phy.label		= "nop-xceiv";
	nop->phy.set_suspend	= nop_set_suspend;
	nop->phy.state		= OTG_STATE_UNDEFINED;

	nop->phy.otg->phy		= &nop->phy;
	nop->phy.otg->set_host		= nop_set_host;
	nop->phy.otg->set_peripheral	= nop_set_peripheral;

	err = usb_set_transceiver(&nop->phy);
	if (err) {
		dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
			err);
		goto exit;
	}

	platform_set_drvdata(pdev, nop);

	ATOMIC_INIT_NOTIFIER_HEAD(&nop->phy.notifier);

	return 0;
exit:
	kfree(nop->phy.otg);
	kfree(nop);
	return err;
}

static int __devexit nop_usb_xceiv_remove(struct platform_device *pdev)
{
	struct nop_usb_xceiv *nop = platform_get_drvdata(pdev);

	usb_set_transceiver(NULL);

	platform_set_drvdata(pdev, NULL);
	kfree(nop->phy.otg);
	kfree(nop);

	return 0;
}

static struct platform_driver nop_usb_xceiv_driver = {
	.probe		= nop_usb_xceiv_probe,
	.remove		= __devexit_p(nop_usb_xceiv_remove),
	.driver		= {
		.name	= "nop_usb_xceiv",
		.owner	= THIS_MODULE,
	},
};

static int __init nop_usb_xceiv_init(void)
{
	return platform_driver_register(&nop_usb_xceiv_driver);
}
subsys_initcall(nop_usb_xceiv_init);

static void __exit nop_usb_xceiv_exit(void)
{
	platform_driver_unregister(&nop_usb_xceiv_driver);
}
module_exit(nop_usb_xceiv_exit);

MODULE_ALIAS("platform:nop_usb_xceiv");
MODULE_AUTHOR("Texas Instruments Inc");
MODULE_DESCRIPTION("NOP USB Transceiver driver");
MODULE_LICENSE("GPL");